Commit Graph

8268 Commits

Author SHA1 Message Date
Luís Marques 27e6b171e0 [RISCV][Docs] Add RISC-V asm template argument modifiers
Adds the RISC-V asm template argument modifiers currently supported by LLVM.
Additional ones supported by GCC will be added to the documentation when we
start supporting them.
2020-01-07 11:06:46 +00:00
serge_sans_paille 24ab9b537e Generalize the pass registration mechanism used by Polly to any third-party tool
There's quite a lot of references to Polly in the LLVM CMake codebase. However
the registration pattern used by Polly could be useful to other external
projects: thanks to that mechanism it would be possible to develop LLVM
extension without touching the LLVM code base.

This patch has two effects:

1. Remove all code specific to Polly in the llvm/clang codebase, replaicing it
   with a generic mechanism

2. Provide a generic mechanism to register compiler extensions.

A compiler extension is similar to a pass plugin, with the notable difference
that the compiler extension can be configured to be built dynamically (like
plugins) or statically (like regular passes).

As a result, people willing to add extra passes to clang/opt can do it using a
separate code repo, but still have their pass be linked in clang/opt as built-in
passes.

Differential Revision: https://reviews.llvm.org/D61446
2020-01-02 16:45:31 +01:00
Jinsong Ji 0bd3cc4248 [PowerPC][docs] Update Embedded PowerPC docs in Compiler Writers Info page
Summary:
Embedded PowerPC are still actively supported, especially SPE...
So update some important references here:

* adding EREF
* adding SPE/VLE ref

Delete deprecated ones into "Other documents..".

Reviewers: #powerpc, jhibbits, hfinkel

Reviewed By: #powerpc, jhibbits

Subscribers: wuzish, merge_guards_bot, nemanjai, shchenz, steven.zhang, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D72008
2019-12-30 20:22:37 +00:00
Fangrui Song 03b9f0a5e1 Ignore "no-frame-pointer-elim" and "no-frame-pointer-elim-non-leaf" in favor of "frame-pointer"
D56351 (included in LLVM 8.0.0) introduced "frame-pointer".  All tests
which use "no-frame-pointer-elim" or "no-frame-pointer-elim-non-leaf"
have been migrated to use "frame-pointer".

Implement UpgradeFramePointerAttributes to upgrade the two obsoleted
function attributes for bitcode. Their semantics are ignored.

Differential Revision: https://reviews.llvm.org/D71863
2019-12-30 09:46:19 -08:00
Dmitry Preobrazhensky 80c45e49c3 [AMDGPU][MC][DOC] Updated AMD GPU assembler syntax description.
Summary of changes:
- added description of GFX9 subtargets:
  - gfx900;
  - gfx902;
  - gfx904;
  - gfx906;
  - gfx908;
  - gfx909.
2019-12-25 17:51:53 +03:00
Fangrui Song 502a77f125 Migrate function attribute "no-frame-pointer-elim" to "frame-pointer"="all" as cleanups after D56351 2019-12-24 15:57:33 -08:00
Sylvestre Ledru 2026d7b80a VariableName doc: fix the link to the mozilla doc 2019-12-24 13:39:22 +01:00
Alex Zinenko a28b65b279 [docs] fix typo in Lexicon.rst
Differential revision: https://reviews.llvm.org/D71844
2019-12-24 09:47:15 +01:00
Florian Hahn 5762648c46 [Docs] Fix sphinx build errors. 2019-12-23 21:53:30 +01:00
Nico Weber 9b6ad8466b fix another doc typo to cycle bots 2019-12-20 21:59:51 -05:00
Petr Hosek dedad08ee8 [llvm-symbolizer] Support reading options from environment
llvm-symbolizer is used by sanitizers to symbolize errors discovered by
sanitizer, but there's no way to pass options to llvm-symbolizer since
the tool is invoked directly by the sanitizer runtime. Therefore, we
don't have a way to pass options needed to find debug symbols such as
-dsym-hint or -debug-file-directory. This change enables reading options
from the LLVM_SYMBOLIZER_OPTS in addition to command line which can be
used to pass those additional options to llvm-symbolizer invocations
made by sanitizer runtime.

Differential Revision: https://reviews.llvm.org/D71668
2019-12-20 12:47:27 -08:00
Yuanfang Chen 6218696bc9
[Docs] Fix a typo 2019-12-18 15:19:01 -08:00
Ulrich Weigand 1946461344 [FPEnv] Strict versions of llvm.minimum/llvm.maximum
Add new intrinsics
   llvm.experimental.constrained.minimum
   llvm.experimental.constrained.maximum
as strict versions of llvm.minimum and llvm.maximum.

Includes SystemZ back-end support.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D71624
2019-12-18 21:35:28 +01:00
Richard Smith b6e90a1a10 llvm-cxxmap: fix support for remapping non-mangled names.
Remappings involving extern "C" names were already supported in the
context of <local-name>s, but this support didn't work for remapping the
complete mangling itself. (Eg, we would remap X<foo> but not foo itself,
if foo is an extern "C" function.)
2019-12-18 10:47:02 -08:00
Justin Bogner b6f5caa48f [docs] Remove `git llvm push` and `git llvm revert` from GettingStarted
These sections aren't accurate since the github move.

Differential Revision: https://reviews.llvm.org/D71640
2019-12-17 17:16:20 -08:00
Ulrich Weigand 1e89188d35 [FPEnv] Remove unnecessary rounding mode argument for constrained intrinsics
The following intrinsics currently carry a rounding mode metadata argument:

    llvm.experimental.constrained.minnum
    llvm.experimental.constrained.maxnum
    llvm.experimental.constrained.ceil
    llvm.experimental.constrained.floor
    llvm.experimental.constrained.round
    llvm.experimental.constrained.trunc

This is not useful since the semantics of those intrinsics do not in any way
depend on the rounding mode. In similar cases, other constrained intrinsics
do not have the rounding mode argument. Remove it here as well.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D71218
2019-12-17 21:10:36 +01:00
Kevin P. Neal b1d8576b0a This adds constrained intrinsics for the signed and unsigned conversions
of integers to floating point.

This includes some of Craig Topper's changes for promotion support from
D71130.

Differential Revision: https://reviews.llvm.org/D69275
2019-12-17 10:06:51 -05:00
Dmitri Gribenko 51707196a0 Fix title underline in LangRef
The docs didn't compile:
http://lab.llvm.org:8011/builders/llvm-sphinx-docs/builds/38906
2019-12-16 09:05:13 +01:00
Seiya Nuta 9e119ad69d
[llvm-objcopy][MachO] Implement --add-section
Reviewers: alexshap, rupprecht, jhenderson

Reviewed By: alexshap, jhenderson

Subscribers: mgorny, jakehehrlich, abrachet, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66283
2019-12-16 14:07:29 +09:00
Kristina Bessonova d5655c4d2e [llvm-dwarfdump][Statistics] Don't count coverage less than 1% as 0%
Summary:
This is a follow up for D70548.
Currently, variables with debug info coverage between 0% and 1% are put into
zero-bucket. D70548 changed the way statistics calculate a variable's coverage:
we began to use enclosing scope rather than a possible variable life range.
Thus more variables might be moved to zero-bucket despite they have some debug
info coverage.
The patch is to distinguish between a variable that has location info but
it's significantly less than its enclosing scope and a variable that doesn't
have it at all.

Reviewers: djtodoro, aprantl, dblaikie, avl

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71070
2019-12-13 17:34:58 +03:00
Kristina Bessonova 1cc4b603ba [llvm-dwarfdump][Statistics] Change the coverage buckets representation. NFC
Summary:
This changes the representation of 'coverage buckets' in llvm-dwarfdump and
llvm-locstats to one that makes more clear what the buckets contain.

See some related details in D71070.

Reviewers: djtodoro, aprantl, cmtice, jhenderson

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71366
2019-12-13 16:08:25 +03:00
Kai Nacke caa7c9e6f3 [Docs] Fix target feature matrix for PowerPC and SystemZ
The target feature matrix in the code generator documentation is
outdated. This PR fixes some entries for PowerPC and SystemZ.

Both have:
- assembly parser
- disassembler
- .o file writing

Reviewers: uweigand

Differential Revision: https://reviews.llvm.org/D71004
2019-12-13 06:18:08 -05:00
Tony 7a54f727a2 [AMDGPU] AMDGPUUsage clarify address space information and other typo and formatting fixes
Summary:
- Clarify AMDGPU address spaces.
- Correct path to AMDGPU backend since now in the mono-repo.
- Fix numerous text style and typo issues.
- Correct reStructure text formatting warnings.
- Made reStructure directive usage more consistent.
- Add references for gfx10 ISA specification.

Subscribers: kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, jfb, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71392
2019-12-12 14:51:27 -05:00
Florian Hahn 526244b187 [Matrix] Add first set of matrix intrinsics and initial lowering pass.
This is the first patch adding an initial set of matrix intrinsics and a
corresponding lowering pass. This has been discussed on llvm-dev:
http://lists.llvm.org/pipermail/llvm-dev/2019-October/136240.html

The first patch introduces four new intrinsics (transpose, multiply,
columnwise load and store) and a LowerMatrixIntrinsics pass, that
lowers those intrinsics to vector operations.

Matrixes are embedded in a 'flat' vector (e.g. a 4 x 4 float matrix
embedded in a <16 x float> vector) and the intrinsics take the dimension
information as parameters. Those parameters need to be ConstantInt.
For the memory layout, we initially assume column-major, but in the RFC
we also described how to extend the intrinsics to support row-major as
well.

For the initial lowering, we split the input of the intrinsics into a
set of column vectors, transform those column vectors and concatenate
the result columns to a flat result vector.

This allows us to lower the intrinsics without any shape propagation, as
mentioned in the RFC. In follow-up patches, we plan to submit the
following improvements:
 * Shape propagation to eliminate the embedding/splitting for each
   intrinsic.
 * Fused & tiled lowering of multiply and other operations.
 * Optimization remarks highlighting matrix expressions and costs.
 * Generate loops for operations on large matrixes.
 * More general block processing for operation on large vectors,
   exploiting shape information.

We would like to add dedicated transpose, columnwise load and store
intrinsics, even though they are not strictly necessary. For example, we
could instead emit a large shufflevector instruction instead of the
transpose. But we expect that to
  (1) become unwieldy for larger matrixes (even for 16x16 matrixes,
      the resulting shufflevector masks would be huge),
  (2) risk instcombine making small changes, causing us to fail to
      detect the transpose, preventing better lowerings

For the load/store, we are additionally planning on exploiting the
intrinsics for better alias analysis.

Reviewers: anemet, Gerolf, reames, hfinkel, andrew.w.kaylor, efriedma, rengolin

Reviewed By: anemet

Differential Revision: https://reviews.llvm.org/D70456
2019-12-12 15:42:18 +00:00
Simon Tatham 1fed9a0c0c [TableGen] Add bang-operators !getop and !setop.
Summary:
These allow you to get and set the operator of a dag node, without
affecting its list of arguments.

`!getop` is slightly fiddly because in many contexts you need its
return value to have a static type more specific than 'any record'. It
works to say `!cast<BaseClass>(!getop(...))`, but it's cumbersome, so
I made `!getop` take an optional type suffix itself, so that can be
written as the shorter `!getop<BaseClass>(...)`.

Reviewers: hfinkel, nhaehnle

Reviewed By: nhaehnle

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71191
2019-12-11 12:05:22 +00:00
Sanjay Patel a0c558ee4c [Docs] Improve SLP code snippet
New C code snippet is more viable for SLP vectorization in most architectures.

Patch by: @lsandov1 (Leonardo Sandoval)

Differential Revision: https://reviews.llvm.org/D70866
2019-12-10 09:32:40 -05:00
Nico Weber 761dd780ea Fix a few doc typos, to cycle bots. 2019-12-08 18:51:48 -05:00
Ulrich Weigand 9db13b5a7d [FPEnv] Constrained FCmp intrinsics
This adds support for constrained floating-point comparison intrinsics.

Specifically, we add:

      declare <ty2>
      @llvm.experimental.constrained.fcmp(<type> <op1>, <type> <op2>,
                                          metadata <condition code>,
                                          metadata <exception behavior>)
      declare <ty2>
      @llvm.experimental.constrained.fcmps(<type> <op1>, <type> <op2>,
                                           metadata <condition code>,
                                           metadata <exception behavior>)

The first variant implements an IEEE "quiet" comparison (i.e. we only
get an invalid FP exception if either argument is a SNaN), while the
second variant implements an IEEE "signaling" comparison (i.e. we get
an invalid FP exception if either argument is any NaN).

The condition code is implemented as a metadata string.  The same set
of predicates as for the fcmp instruction is supported (except for the
"true" and "false" predicates).

These new intrinsics are mapped by SelectionDAG codegen onto two new
ISD opcodes, ISD::STRICT_FSETCC and ISD::STRICT_FSETCCS, again
representing quiet vs. signaling comparison operations.  Otherwise
those nodes look like SETCC nodes, with an additional chain argument
and result as usual for strict FP nodes.  The patch includes support
for the common legalization operations for those nodes.

The patch also includes full SystemZ back-end support for the new
ISD nodes, mapping them to all available SystemZ instruction to
fully implement strict semantics (scalar and vector).

Differential Revision: https://reviews.llvm.org/D69281
2019-12-07 11:28:39 +01:00
Don Hinton 6555995a6d [CommandLine] Add callbacks to Options
Summary:
Add a new cl::callback attribute to Option.

This attribute specifies a callback function that is called when
an option is seen, and can be used to set other options, as in
option A implies option B.  If the option is a `cl::list`, and
`cl::CommaSeparated` is also specified, the callback will fire
once for each value.  This could be used to validate combinations
or selectively set other options.

Reviewers: beanz, thomasfinch, MaskRay, thopre, serge-sans-paille

Reviewed By: beanz

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70620
2019-12-06 15:16:45 -08:00
Nico Weber 3b42eb3512 wrap an rst file to 80 cols, to cycle bots 2019-12-06 17:28:02 -05:00
Georgii Rymar cd2c409ceb [llvm-readobj] - Implement --dependent-libraries flag.
There is no way to dump SHT_LLVM_DEPENDENT_LIBRARIES sections
currently. This patch implements this.

The section is described here:
https://llvm.org/docs/Extensions.html#sht-llvm-dependent-libraries-section-dependent-libraries

Differential revision: https://reviews.llvm.org/D70665
2019-12-06 14:28:29 +03:00
Daniel Sanders 82f3c5d4a6 [lit] Document the undocumented pre-defined substitutions 2019-12-04 14:25:12 -08:00
Sanjay Patel ead0d77409 [LangRef] make per-element poison behavior explicit
As discussed in D70246 and PR43958:
https://bugs.llvm.org/show_bug.cgi?id=43958

The LangRef seems ambiguous about the behavior of poison with respect
to vectors.

We could go further with text and/or examples - suggestions welcome.

Also, see discussion on llvm-dev;
http://lists.llvm.org/pipermail/llvm-dev/2019-November/137243.html

Differential Revision: https://reviews.llvm.org/D70641
2019-12-04 15:32:19 -05:00
Vedant Kumar f208b70fbc Revert "[Coverage] Revise format to reduce binary size"
This reverts commit e18531595b.

On Windows, there is an error:

http://lab.llvm.org:8011/builders/sanitizer-windows/builds/54963/steps/stage%201%20check/logs/stdio

error: C:\b\slave\sanitizer-windows\build\stage1\projects\compiler-rt\test\profile\Profile-x86_64\Output\instrprof-merging.cpp.tmp.v1.o: Failed to load coverage: Malformed coverage data
2019-12-04 10:35:14 -08:00
Vedant Kumar e18531595b [Coverage] Revise format to reduce binary size
Revise the coverage mapping format to reduce binary size by:

1. Naming function records and marking them `linkonce_odr`, and
2. Compressing filenames.

This shrinks the size of llc's coverage segment by 82% (334MB -> 62MB)
and speeds up end-to-end single-threaded report generation by 10%. For
reference the compressed name data in llc is 81MB (__llvm_prf_names).

Rationale for changes to the format:

- With the current format, most coverage function records are discarded.
  E.g., more than 97% of the records in llc are *duplicate* placeholders
  for functions visible-but-not-used in TUs. Placeholders *are* used to
  show under-covered functions, but duplicate placeholders waste space.

- We reached general consensus about giving (1) a try at the 2017 code
  coverage BoF [1]. The thinking was that using `linkonce_odr` to merge
  duplicates is simpler than alternatives like teaching build systems
  about a coverage-aware database/module/etc on the side.

- Revising the format is expensive due to the backwards compatibility
  requirement, so we might as well compress filenames while we're at it.
  This shrinks the encoded filenames in llc by 86% (12MB -> 1.6MB).

See CoverageMappingFormat.rst for the details on what exactly has
changed.

Fixes PR34533 [2], hopefully.

[1] http://lists.llvm.org/pipermail/llvm-dev/2017-October/118428.html
[2] https://bugs.llvm.org/show_bug.cgi?id=34533

Differential Revision: https://reviews.llvm.org/D69471
2019-12-04 10:10:55 -08:00
Kit Barton 06911aee7f Add discussion of git-format-patch to Phabricator.html
Summary: There is a discussion of git-format-patch in GettingStarted guide, but no mention of it in the Phabricator.html page.

Reviewers: jyknight, delcypher

Reviewed By: delcypher

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69323
2019-12-03 18:54:46 -05:00
Sourabh Singh Tomar f1e3988aa6 Recommit "[DWARF5]Addition of alignment atrribute in typedef DIE."
This revision is revised to update Go-bindings and Release Notes.

The original commit message follows.

This patch, adds support for DW_AT_alignment[DWARF5] attribute, to be emitted with typdef DIE.
When explicit alignment is specified.

Patch by Awanish Pandey <Awanish.Pandey@amd.com>

Reviewers: aprantl, dblaikie, jini.susan.george, SouraVX, alok,
deadalinx

Differential Revision: https://reviews.llvm.org/D70111
2019-12-03 09:51:43 +05:30
Seiya Nuta d72a8a4dd5
[llvm-objcopy][MachO] Implement --dump-section
Reviewers: alexshap, rupprecht, jhenderson

Reviewed By: alexshap, rupprecht, jhenderson

Subscribers: MaskRay, jakehehrlich, abrachet, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66408
2019-11-25 12:30:37 +09:00
Joel E. Denny f471eb8e99 [FileCheck] Make FILECHECK_OPTS useful for its test suite
Without this patch, `FILECHECK_OPTS` isn't propagated to FileCheck's
test suite so that `FILECHECK_OPTS` doesn't inadvertently affect test
results by affecting the output of FileCheck calls under test.  As a
result, `FILECHECK_OPTS` is useless for debugging FileCheck's test
suite.

In `llvm/test/FileCheck/lit.local.cfg`, this patch provides a new
subsitution, `%ProtectFileCheckOutput`, to address this problem for
both `FILECHECK_OPTS` and the deprecated
`FILECHECK_DUMP_INPUT_ON_FAILURE`.  The rest of the patch uses
`%ProtectFileCheckOutput` throughout the test suite

Fixes PR40284.

Reviewed By: probinson, thopre

Differential Revision: https://reviews.llvm.org/D65121
2019-11-21 18:01:12 -05:00
Dmitri Gribenko 161742a612 Make coding standards document more inclusive
Summary: Patch by Doug Gregor, Tres Popp, and Dmitri Gribenko.

Reviewers: chandlerc

Subscribers: hfinkel, bmcreusillet, arsenm, doug.gregor, mgrang, arphaman, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69354
2019-11-21 13:37:17 +01:00
Josh Kunz 6760ca8c76 [docs] Tiny rewording in the portability FAQ entry
The entry reads better with these two words swapped.
2019-11-20 16:40:30 -08:00
Djordje Todorovic 979592a6f7 [DebugInfo] Remove the DIFlagArgumentNotModified debug info flag
Due to changes in D68206, we remove the DIFlagArgumentNotModified
and its usage.

Differential Revision: https://reviews.llvm.org/D68207
2019-11-20 13:18:40 +01:00
Sameer Sahasrabuddhe 52c5014da0 [AMDGPU] add support for hostcall buffer pointer as hidden kernel argument
Hostcall is a service that allows a kernel to submit requests to the
host using shared buffers, and block until a response is
received. This will eventually replace the shared buffer currently
used for printf, and repurposes the same hidden kernel argument. This
change introduces a new ValueKind in the HSA metadata to represent the
hostcall buffer.

Differential Revision: https://reviews.llvm.org/D70038
2019-11-20 15:53:55 +05:30
Fangrui Song 7d980319ab [FEnv] Fix AddingConstrainedIntrinsics.rst after llvmorg-10-init-10282-g0c50c0b0552 2019-11-19 23:09:13 -08:00
Serge Pavlov 0c50c0b055 [FEnv] File with properties of constrained intrinsics
Summary
In several places we need to enumerate all constrained intrinsics or IR
nodes that should be represented by them. It is easy to miss some of
the cases. To make working with these intrinsics more convenient and
robust, this change introduces file containing definitions of all
constrained intrinsics and some of their properties. This file can be
included to generate constrained intrinsics processing code.

Reviewers: kpn, andrew.w.kaylor, cameron.mcinally, uweigand

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69887
2019-11-20 13:30:07 +07:00
Tim Northover 75b5db3094 [docs] Remove dangling parenthesis from documentation
Patch by leiteg.
2019-11-19 20:47:21 +00:00
Brian Gesiak 5864cb38da [docs] Fix broken links in Kaleidoscope chapter 3
Several links in this document referred to `LangImpl4.html` or
`LangImpl7.html`. However, now these pages use two digits, so for these
links to function they need to be modified to `LangImpl04.html`, and so
on -- note the extra `0`.
2019-11-17 21:35:02 -05:00
kristina 5e782e74b3 [Docs] Remove stray :doc: directive. 2019-11-16 23:32:48 +00:00
kristina fb55d56fcf [Docs] Fix sphinx warning.
Fix sphinx warning over an ambigious reference.
2019-11-16 23:23:26 +00:00
kristina 63cf704081 [Docs] Try fixing the tutorial toctree
Unorphan the old tutorial and reference every page in the index
explicitly. This should hopefully make Sphinx generate correct
hyperlinks now.
2019-11-16 23:06:50 +00:00
kristina 2916489c54 [Docs] Fix relative links in tutorial.
Update relative links in Kaleidoscope tutorial.
2019-11-16 21:09:16 +00:00
Seiya Nuta bc11830c6a
[llvm-objcopy][MachO] Implement --remove-section
Reviewers: alexshap, rupprecht, jhenderson

Reviewed By: rupprecht, jhenderson

Subscribers: jakehehrlich, abrachet, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66282
2019-11-15 14:20:11 +09:00
Kevin P. Neal d2b6cc7ff6 Document more specifically the rounding for "llvm.round".
Differential Revision: https://reviews.llvm.org/D68810
2019-11-14 13:15:15 -05:00
Kevin P. Neal 56ae3e2692 Make the language more consistent since I'm about to commit a content
change next.
2019-11-14 13:10:59 -05:00
Reid Kleckner 1dfede3122 Move CodeGenFileType enum to Support/CodeGen.h
Avoids the need to include TargetMachine.h from various places just for
an enum. Various other enums live here, such as the optimization level,
TLS model, etc. Data suggests that this change probably doesn't matter,
but it seems nice to have anyway.
2019-11-13 16:39:34 -08:00
Fangrui Song 7af6025bd1 [llvm-objcopy][COFF] Implement --redefine-sym and --redefine-syms
The parsing error tests in ELF/redefine-symbols.test are not specific to ELF.
Move them to redefine-symbols.test.
Add COFF/redefine-symbols.test for COFF specific tests.

Also fix the documentation regarding --redefine-syms: the old and new
names are separated by whitespace, not an equals sign.

Reviewed By: mstorsjo

Differential Revision: https://reviews.llvm.org/D70036
2019-11-12 11:28:00 -08:00
Nuno Lopes a7244c56bd docs: fix warning in LangRef parsing 2019-11-11 10:45:42 +00:00
drichards-87 bcca123bd0 Docs: Updates Sphinx Quickstart template for new contributors 2019-11-10 09:27:32 -07:00
Simon Pilgrim 1dbcf8ba8a Try to fix sphinx "Could not lex literal_block as "llvm"" warning.
Code block isn't IR - so treat it as "none" instead.
2019-11-09 22:15:26 +00:00
Stephan T. Lavavej 3a7a22445e [www] More HTTPS and outdated link fixes.
Resolves D69981.
2019-11-08 14:41:27 -08:00
Tom Stellard 3ffbf9720f [cmake] Remove LLVM_{BUILD,LINK}_LLVM_DYLIB options on Windows
Summary: The options aren't supported so they can be removed.

Reviewers: beanz, smeenai, compnerd

Reviewed By: compnerd

Subscribers: mgorny, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69877
2019-11-08 10:37:16 -08:00
Lang Hames baaa097360 [docs] Fix references to a renamed flag.
The -use-mcjit option was replaced with -jit-kind=mcjit a while back. This patch
updates the docs to reflect that.

Patch by Yu Jian. Thanks Jian!
2019-11-06 14:42:57 -08:00
Daniel Sanders e0dd8f36ce [globalisel][docs] Rework GMIR documentation and add an early GenericOpcode reference
It looks like I pushed an older version of this commit without the review
fixups earlier. This applies the review changes

Differential Revision: https://reviews.llvm.org/D69545
2019-11-05 15:44:26 -08:00
Daniel Sanders ad0dfb0a25 [globalisel][docs] Rework GMIR documentation and add an early GenericOpcode reference
Summary:
Rework the GMIR documentation to focus more on the end user than the
implementation and tie it in to the MIR document. There was also some
out-of-date information which has been removed.

The quality of the GenericOpcode reference is highly variable and drops
sharply as I worked through them all but we've got to start somewhere :-).
It would be great if others could expand on this too as there is an awful
lot to get through.

Also fix a typo in the definition of G_FLOG. Previously, the comments said
we had two base-2's (G_FLOG and G_FLOG2).

Reviewers: aemerson, volkan, rovka, arsenm

Reviewed By: rovka

Subscribers: wdng, arphaman, jfb, Petar.Avramovic, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69545
2019-11-05 15:16:43 -08:00
Daniel Sanders 7060840bc9 [globalisel][docs] Add a section about debugging with the block extractor
Summary: Depends on D69644

Reviewers: rovka, volkan, arsenm

Subscribers: wdng, Petar.Avramovic, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69645
2019-11-05 14:48:27 -08:00
Daniel Sanders 312932a334 [globalisel][docs] Add KnownBits Analysis documentation
Summary:
This is largely based off of the slides from the keynote

Depends on D69545

Reviewers: volkan, rovka, arsenm

Subscribers: wdng, arphaman, Petar.Avramovic, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69644
2019-11-05 09:55:33 -08:00
Fangrui Song 5ad0103d8a [llvm-objcopy][ELF] Implement --only-keep-debug
--only-keep-debug produces a debug file as the output that only
preserves contents of sections useful for debugging purposes (the
binutils implementation preserves SHT_NOTE and non-SHF_ALLOC sections),
by changing their section types to SHT_NOBITS and rewritting file
offsets.

See https://sourceware.org/gdb/onlinedocs/gdb/Separate-Debug-Files.html

The intended use case is:

```
llvm-objcopy --only-keep-debug a a.dbg
llvm-objcopy --strip-debug a b
llvm-objcopy --add-gnu-debuglink=a.dbg b
```

The current layout algorithm is incapable of deleting contents and
shrinking segments, so it is not suitable for implementing the
functionality.

This patch adds a new algorithm which assigns sh_offset to sections
first, then modifies p_offset/p_filesz of program headers. It bears a
resemblance to lld/ELF/Writer.cpp.

Reviewed By: jhenderson, jakehehrlich

Differential Revision: https://reviews.llvm.org/D67137
2019-11-05 08:56:15 -08:00
Nuno Lopes 2d21068d9f [Docs] Add LangRef documentation for freeze instruction
Summary:
 - Describe the new freeze instruction
 - Make it explicit that branch on undef/poison is UB

Reviewers: chandlerc, majnemer, efriedma, nikic, reames, jdoerfert, lebedev.ri, regehr

Subscribers: fhahn, bollu, lebedev.ri, delcypher, spatel, filcab, llvm-commits, aqjune

Differential Revision: https://reviews.llvm.org/D29121
2019-11-05 11:35:55 +00:00
Craig Topper b2b6a54f84 [X86] Add support for -mvzeroupper and -mno-vzeroupper to match gcc
-mvzeroupper will force the vzeroupper insertion pass to run on
CPUs that normally wouldn't. -mno-vzeroupper disables it on CPUs
where it normally runs.

To support this with the default feature handling in clang, we
need a vzeroupper feature flag in X86.td. Since this flag has
the opposite polarity of the fast-partial-ymm-or-zmm-write we
used to use to disable the pass, we now need to add this new
flag to every CPU except KNL/KNM and BTVER2 to keep identical
behavior.

Remove -fast-partial-ymm-or-zmm-write which is no longer used.

Differential Revision: https://reviews.llvm.org/D69786
2019-11-04 11:03:54 -08:00
Amy Huang ab76cfdd20 Recommit "[CodeView] Add option to disable inline line tables."
This reverts commit 004ed2b0d1.
Original commit hash 6d03890384

Summary:
This adds a clang option to disable inline line tables. When it is used,
the inliner uses the call site as the location of the inlined function instead of
marking it as an inline location with the function location.

https://reviews.llvm.org/D67723
2019-11-04 09:15:26 -08:00
Stefan Stipanovic f35740d6e9 NoFree argument attribute.
Summary: Deducing nofree atrribute for function arguments.

Reviewers: jdoerfert

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67886
2019-11-02 19:40:48 +01:00
Stefan Stipanovic 5fb1782918 Revert "NoFree argument attribute."
This reverts commit c12efa2ed0.
2019-11-02 17:31:02 +01:00
Stefan Stipanovic c12efa2ed0 NoFree argument attribute.
Summary: Deducing nofree atrribute for function arguments.

Reviewers: jdoerfert

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67886
2019-11-02 16:35:38 +01:00
Roman Lebedev c4b757be02
Revert BCmp Loop Idiom recognition transform (PR43870)
As discussed in https://bugs.llvm.org/show_bug.cgi?id=43870,
this transform is missing a crucial legality check:
the old (non-countable) loop would early-return upon first mismatch,
but there is no such guarantee for bcmp/memcmp.

We'd need to ensure that [PtrA, PtrA+NBytes) and [PtrB, PtrB+NBytes)
are fully dereferenceable memory regions. But that would limit
the transform to constant loop trip counts and would further
cripple it because dereferenceability analysis is *very* partial.

Furthermore, even if all that is done, every single test
would need to be rewritten from scratch.

So let's just give up.
2019-11-02 12:48:03 +03:00
Evgenii Stepanov 27c9abae65 Add MemTagSanitizer documentation.
Summary: A lot of this is work in progress...

Reviewers: kcc, pcc

Subscribers: cryptoad, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69289
2019-11-01 10:46:04 -07:00
Adrian Prantl 9370a74158 Fix a few typos in SourceLevelDebugging.rst 2019-10-31 16:03:44 -07:00
James Henderson fb4a55010e [llvm-objcopy] Preserve .ARM.attributes section when stripping files
This works around a bug in Debian's patchset for glibc. The bug is
described in detail in the upstream debian bug:
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=943798, but the short
version of it is that glibc on any Debian based distro don't load
libraries unless it has a .ARM.attribute section.

Reviewed by: jhenderson, rupprecht, MaskRay, jakehehrlich

Differential Revision: https://reviews.llvm.org/D69188

Patch by Tobias Hieta.
2019-10-31 11:57:19 +00:00
Seiya Nuta 9bbf2a1544
[llvm-objcopy][MachO] Implement --strip-all
Reviewers: alexshap, rupprecht, jdoerfert, jhenderson

Reviewed By: alexshap

Subscribers: jakehehrlich, abrachet, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66281
2019-10-31 14:26:46 +09:00
Amy Huang 004ed2b0d1 Revert "[CodeView] Add option to disable inline line tables."
because it breaks compiler-rt tests.

This reverts commit 6d03890384.
2019-10-30 17:31:12 -07:00
Amy Huang 6d03890384 [CodeView] Add option to disable inline line tables.
Summary:
This adds a clang option to disable inline line tables. When it is used,
the inliner uses the call site as the location of the inlined function instead of
marking it as an inline location with the function location.

See https://bugs.llvm.org/show_bug.cgi?id=42344

Reviewers: rnk

Subscribers: hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D67723
2019-10-30 16:52:39 -07:00
Daniel Sanders 204a529cb0 [globalisel][docs] Add the tutorial to the Porting document
In lieu of converting that tutorial to text, add a link to the porting
tutorial from the 2017 Dev Meeting to the porting page
2019-10-30 14:53:39 -07:00
Alina Sbirlea bbb43df011 [ReleaseNotes] Add item on deleting the BasicBlockPass(Manager). 2019-10-30 14:26:46 -07:00
Daniel Sanders 2d098bea03 [globalisel][docs] Rework the Legalizer page slightly
The legalizer page was in a fairly good state. I've mostly just inlined
some information as a note and removed a reference to potential future
work that I think is very unlikely to be done (it's very hard to tell if
a pattern or set of patterns fully covers a node due to C++ predicates).

Also added a note that 'selectable' doesn't mean that InstructionSelect
must do it.
2019-10-30 13:42:19 -07:00
Evandro Menezes 215da6606c [clang][llvm] Obsolete Exynos M1 and M2 2019-10-30 15:02:59 -05:00
Daniel Sanders 91e2151d04 [globalisel][docs] Add a pass index 2019-10-30 12:06:22 -07:00
Daniel Sanders 443f99eae2 [globalisel][docs] Fix a label that was renamed 2019-10-30 11:47:29 -07:00
Alina Sbirlea 9f0ff0b263 [LegacyPassManager] Delete BasicBlockPass/Manager.
Summary:
Delete the BasicBlockPass and BasicBlockManager, all its dependencies and update documentation.
The BasicBlockManager was improperly tested and found to be potentially broken, and was deprecated as of rL373254.

In light of the switch to the new pass manager coming before the next release, this patch is a first cleanup of the LegacyPassManager.

Reviewers: chandlerc, echristo

Subscribers: mehdi_amini, sanjoy.google, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69121
2019-10-30 11:40:16 -07:00
Jay Foad 2da4b6e514 [IR] Allow fast math flags on calls with floating point array type.
Summary:
This extends the rules for when a call instruction is deemed to be an
FPMathOperator, which is based on the type of the call (i.e. the return
type of the function being called). Previously we only allowed
floating-point and vector-of-floating-point types. Now we also allow
arrays (nested to any depth) of floating-point and
vector-of-floating-point types.

This was motivated by llpc, the pipeline compiler for AMD GPUs
(https://github.com/GPUOpen-Drivers/llpc). llpc has many math library
functions that operate on vectors, typically represented as <4 x float>,
and some that operate on matrices, typically represented as
[4 x <4 x float>], and it's useful to be able to decorate calls to all
of them with fast math flags.

Reviewers: spatel, wristow, arsenm, hfinkel, aemerson, efriedma, cameron.mcinally, mcberg2017, jmolloy

Subscribers: wdng, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69161
2019-10-30 14:00:33 +00:00
Vlad Tsyrklevich 8d24d72f7f Revert "[llvm-cov] Add option to whitelist filenames"
This reverts commit bfed824b57, the
included test fails on many bots including the sanitier bots, e.g. in
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-fast/builds/36140
2019-10-29 22:38:38 -07:00
Vedant Kumar bfed824b57 [llvm-cov] Add option to whitelist filenames
Add the `-whitelist-filename-regex` option to restrict coverage
reporting to file paths that match a whitelist regex.

Patch by Michael Daniels!

rdar://56720320
2019-10-29 18:26:33 -07:00
Adrian Prantl f919be3365 [DWARF5] Added support for deleted C++ special member functions.
This patch adds support for deleted C++ special member functions in
clang and llvm. Also added Defaulted member encodings for future
support for defaulted member functions.

Patch by Sourabh Singh Tomar!

Differential Revision: https://reviews.llvm.org/D69215
2019-10-29 13:44:06 -07:00
Daniel Sanders 3260fa2cb0 [globalisel][docs] Fix warning treated as error
I had hoped that I could have some
```
.. code-block:: MIR
```
sections for MIR examples which causes a warning about pygments not
supporting it but we have warnings treated as errors
2019-10-29 13:27:48 -07:00
Daniel Sanders 6f665fc786 [globalisel][docs] Rewrite the IRTranslator documentation
Summary:
I haven't refreshed the Function Calls section as I don't feel I have
sufficient knowledge of that area. It would be appreciated if someone could
review that section.

Note: I'm aware that pygments doesn't support 'mir' as used in one of the
code-block directives. This currently emits a warning and I decided to
keep it to enable finding them later. Maybe we can teach pygments to
support it.

Depends on D69456

Reviewers: volkan, aditya_nandakumar

Subscribers: rovka, Petar.Avramovic, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69457
2019-10-29 13:14:58 -07:00
Philip Reames e14f935ce2 [Docs] Reflect the slow migration from guard to widenable condition which is currently in progress. 2019-10-29 12:46:24 -07:00
Daniel Sanders 1765f31f5a [globalisel][docs] Rewrite the pipeline overview
Summary:
Rewrite the pipeline overview to be more focused on the structure and
flexibility as well as highlight the increased usefulness of
MachineVerifier and increased testability resulting from the smaller
incremental passes approach.

The diagrams are lifted from the slides for the LLVMDev 2019 talk
'Generating Optimized Code with GlobalISel' and adapted to be readable on
the white background used in the docs.

Reviewers: volkan

Subscribers: rovka, Petar.Avramovic, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69456
2019-10-29 11:21:24 -07:00
Francis Visoiu Mistrih c7557dd692 [Remarks] Remove references to ELF support
There is no ELF support at the moment.

Remove all the references to the `.remarks` section.
2019-10-28 12:50:46 -07:00
Francis Visoiu Mistrih 209d5a12c5 [Remarks] Emit the remarks section by default for certain formats
Emit a remarks section by default for the following formats:

* bitstream
* yaml-strtab

while still providing -remarks-section=<bool> to override the defaults.
2019-10-28 12:50:46 -07:00
Andrew Paverd d157a9bc8b Add Windows Control Flow Guard checks (/guard:cf).
Summary:
A new function pass (Transforms/CFGuard/CFGuard.cpp) inserts CFGuard checks on
indirect function calls, using either the check mechanism (X86, ARM, AArch64) or
or the dispatch mechanism (X86-64). The check mechanism requires a new calling
convention for the supported targets. The dispatch mechanism adds the target as
an operand bundle, which is processed by SelectionDAG. Another pass
(CodeGen/CFGuardLongjmp.cpp) identifies and emits valid longjmp targets, as
required by /guard:cf. This feature is enabled using the `cfguard` CC1 option.

Reviewers: thakis, rnk, theraven, pcc

Subscribers: ychen, hans, metalcanine, dmajor, tomrittervg, alex, mehdi_amini, mgorny, javed.absar, kristof.beyls, hiraditya, steven_wu, dexonsmith, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D65761
2019-10-28 15:19:39 +00:00
Seiya Nuta 7f19dd1ebf
[llvm-objcopy][MachO] Implement --only-section
Reviewers: alexshap, rupprecht, jdoerfert, jhenderson

Reviewed By: alexshap, rupprecht, jhenderson

Subscribers: mgorny, jakehehrlich, abrachet, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65541
2019-10-28 16:00:20 +09:00
Daniel Sanders feab0334f5 [globalisel] Restructure the GlobalISel documentation
There's a couple minor deletions amongst this but 99% of it is just moving
the documentation around to prepare the way for more meaningful changes.
2019-10-25 15:51:09 -07:00
Daniel Sanders 27887bc1e7 [globalisel] Fix typo in 'Add LLVMDev 2019 talks and links for the 2017 talks' 2019-10-25 15:01:14 -07:00
Daniel Sanders 7913126a08 [globalisel] Add LLVMDev 2019 talks and links for the 2017 talks 2019-10-25 14:53:58 -07:00
Saleem Abdulrasool 2724d9e129 build: remove `LLVM_CXX_STD` extension point
This extension point is not needed. Provide the equivalent option
through `CMAKE_CXX_STANDARD` which mirrors the previous extension point. Rely on
CMake to provide the check for the compiler instead.
2019-10-25 11:51:47 -07:00
Simon Atanasyan 77b3c794e3 [docs] Update Mips feature table in CodeGenerator.rst
Patch by Miloš Stojanović

Differential Revision: https://reviews.llvm.org/D69381
2019-10-25 12:17:34 +03:00
Tom Stellard 27bfee01e9 docs: Update instructions for requesting commit access 2019-10-24 20:42:02 -07:00
Simon Atanasyan fd77e578e9 [docs] Add Mips as a supported architecture in GettingStarted.rst
Patch by Miloš Stojanović

Differential Revision: https://reviews.llvm.org/D69380
2019-10-24 15:56:30 +03:00
Simon Atanasyan c84cfaf9bc [docs] Update link to the MIPS 64-bit ELF object file specification
Patch by Miloš Stojanović

Differential Revision: https://reviews.llvm.org/D69377
2019-10-24 15:56:30 +03:00
Marek Kurdej 73cebfe412 [libFuzzer] docs: update note to include REDUCE event. 2019-10-24 12:04:12 +02:00
Meike Baumgärtner 23fdd513a3
Improve language in GettingStarted.rst
This patch was reviewed and approved by chandlerc.

"Getting Started with the LLVM System" is the first point of contact for many newcomers in the LLVM community.
 * Make the first two paragraphs more welcoming
 * Use more inclusive language
2019-10-23 12:32:57 -07:00
Chandler Carruth bf2975eca0 Remove a no longer accurate sentence from the coding standards.
(And test my commit access. We're working on larger changes here.)
2019-10-23 11:40:45 -07:00
Kit Barton efd7caaa4e Fix broken sphinx link in CMake.rst.
Reviewers: delcypher, beanz

Subscribers: mgorny, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69325
2019-10-22 14:49:58 -07:00
Owen Reynolds fe263c4f0f [docs][llvm-ar] Update llvm-ar command guide
The llvm-ar command guide had not been updated in some time, it was
missing current functionality and contained information that was out
of date. This change:
- Updates the use of reStructuredText directives, as seen in other tools
  command guides.
- Updates the command synopsis.
- Updates the descriptions of the tool behaviour.
- Updates the options section.
- Adds details of MRI script functionality.
- Removes the sections "Standards" and "File Format"

Differential Revision: https://reviews.llvm.org/D68998

llvm-svn: 375412
2019-10-21 13:13:31 +00:00
Sylvestre Ledru 751e0bb6af Explicit in the doc the current list of projects (with easy copy and paste)
llvm-svn: 375339
2019-10-19 09:55:24 +00:00
Sylvestre Ledru 963e0d6755 Make it clear in the doc that 'all' in LLVM_ENABLE_PROJECTS does install ALL projects
llvm-svn: 375337
2019-10-19 09:27:14 +00:00
Jay Foad aa3806b47c Update docs for fast-math flags.
This adds fneg, phi and select to the list of operations that may use
fast-math flags.

llvm-svn: 375250
2019-10-18 16:07:09 +00:00
Jordan Rupprecht edeebad771 [llvm-objcopy] Add support for shell wildcards
Summary: GNU objcopy accepts the --wildcard flag to allow wildcard matching on symbol-related flags. (Note: it's implicitly true for section flags).

The basic syntax is to allow *, ?, \, and [] which work similarly to how they work in a shell. Additionally, starting a wildcard with ! causes that wildcard to prevent it from matching a flag.

Use an updated GlobPattern in libSupport to handle these patterns. It does not fully match the `fnmatch` used by GNU objcopy since named character classes (e.g. `[[:digit:]]`) are not supported, but this should support most existing use cases (mostly just `*` is what's used anyway).

Reviewers: jhenderson, MaskRay, evgeny777, espindola, alexshap

Reviewed By: MaskRay

Subscribers: nickdesaulniers, emaste, arichardson, hiraditya, jakehehrlich, abrachet, seiya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66613

llvm-svn: 375169
2019-10-17 20:51:00 +00:00
Fangrui Song 5095a67a1a [docs][llvm-ar] Fix option:: O after r375106
docs-llvm-html fails => unknown option: O

There are lots of formatting issues in the file but they will be fixed by D68998.

llvm-svn: 375107
2019-10-17 11:56:26 +00:00
Fangrui Song a69cc92cb5 [llvm-ar] Implement the O modifier: display member offsets inside the archive
Since GNU ar 2.31, the 't' operation prints member offsets beside file
names if the 'O' modifier is specified. 'O' is ignored for thin
archives.

Reviewed By: gbreynoo, ruiu

Differential Revision: https://reviews.llvm.org/D69087

llvm-svn: 375106
2019-10-17 11:34:29 +00:00
Oliver Stannard 3b598b9c86 Reland: Dead Virtual Function Elimination
Remove dead virtual functions from vtables with
replaceNonMetadataUsesWith, so that CGProfile metadata gets cleaned up
correctly.

Original commit message:

Currently, it is hard for the compiler to remove unused C++ virtual
functions, because they are all referenced from vtables, which are referenced
by constructors. This means that if the constructor is called from any live
code, then we keep every virtual function in the final link, even if there
are no call sites which can use it.

This patch allows unused virtual functions to be removed during LTO (and
regular compilation in limited circumstances) by using type metadata to match
virtual function call sites to the vtable slots they might load from. This
information can then be used in the global dead code elimination pass instead
of the references from vtables to virtual functions, to more accurately
determine which functions are reachable.

To make this transformation safe, I have changed clang's code-generation to
always load virtual function pointers using the llvm.type.checked.load
intrinsic, instead of regular load instructions. I originally tried writing
this using clang's existing code-generation, which uses the llvm.type.test
and llvm.assume intrinsics after doing a normal load. However, it is possible
for optimisations to obscure the relationship between the GEP, load and
llvm.type.test, causing GlobalDCE to fail to find virtual function call
sites.

The existing linkage and visibility types don't accurately describe the scope
in which a virtual call could be made which uses a given vtable. This is
wider than the visibility of the type itself, because a virtual function call
could be made using a more-visible base class. I've added a new
!vcall_visibility metadata type to represent this, described in
TypeMetadata.rst. The internalization pass and libLTO have been updated to
change this metadata when linking is performed.

This doesn't currently work with ThinLTO, because it needs to see every call
to llvm.type.checked.load in the linkage unit. It might be possible to
extend this optimisation to be able to use the ThinLTO summary, as was done
for devirtualization, but until then that combination is rejected in the
clang driver.

To test this, I've written a fuzzer which generates random C++ programs with
complex class inheritance graphs, and virtual functions called through object
and function pointers of different types. The programs are spread across
multiple translation units and DSOs to test the different visibility
restrictions.

I've also tried doing bootstrap builds of LLVM to test this. This isn't
ideal, because only classes in anonymous namespaces can be optimised with
-fvisibility=default, and some parts of LLVM (plugins and bugpoint) do not
work correctly with -fvisibility=hidden. However, there are only 12 test
failures when building with -fvisibility=hidden (and an unmodified compiler),
and this change does not cause any new failures for either value of
-fvisibility.

On the 7 C++ sub-benchmarks of SPEC2006, this gives a geomean code-size
reduction of ~6%, over a baseline compiled with "-O2 -flto
-fvisibility=hidden -fwhole-program-vtables". The best cases are reductions
of ~14% in 450.soplex and 483.xalancbmk, and there are no code size
increases.

I've also run this on a set of 8 mbed-os examples compiled for Armv7M, which
show a geomean size reduction of ~3%, again with no size increases.

I had hoped that this would have no effect on performance, which would allow
it to awlays be enabled (when using -fwhole-program-vtables). However, the
changes in clang to use the llvm.type.checked.load intrinsic are causing ~1%
performance regression in the C++ parts of SPEC2006. It should be possible to
recover some of this perf loss by teaching optimisations about the
llvm.type.checked.load intrinsic, which would make it worth turning this on
by default (though it's still dependent on -fwhole-program-vtables).

Differential revision: https://reviews.llvm.org/D63932

llvm-svn: 375094
2019-10-17 09:58:57 +00:00
Alina Sbirlea c0e6a92e34 Update ReleaseNotes: expand the section on enabling MemorySSA
llvm-svn: 375045
2019-10-16 21:52:09 +00:00
Owen Reynolds 28a3b2aeb4 [llvm-ar] Make paths case insensitive when on windows
When on windows gnu-ar treats member names as case insensitive. This
commit implements the same behaviour.

Differential Revision: https://reviews.llvm.org/D68033

llvm-svn: 375002
2019-10-16 14:07:57 +00:00
DeForest Richards 75b991ebdf [Docs] Updates sidebar links and sets max-width property for div.body
Updates the sidebar links for Getting Started. Also sets max-width on div.body to 1000px.

llvm-svn: 374949
2019-10-15 21:27:20 +00:00
David Stenberg 1ae2d9a2bd [DebugInfo] Add a DW_OP_LLVM_entry_value operation
Summary:
Internally in LLVM's metadata we use DW_OP_entry_value operations with
the same semantics as DWARF; that is, its operand specifies the number
of bytes that the entry value covers.

At the time of emitting entry values we don't know the emitted size of
the DWARF expression that the entry value will cover. Currently the size
is hardcoded to 1 in DIExpression, and other values causes the verifier
to fail. As the size is 1, that effectively means that we can only have
valid entry values for registers that can be encoded in one byte, which
are the registers with DWARF numbers 0 to 31 (as they can be encoded as
single-byte DW_OP_reg0..DW_OP_reg31 rather than a multi-byte
DW_OP_regx). It is a bit confusing, but it seems like llvm-dwarfdump
will print an operation "correctly", even if the byte size is less than
that, which may make it seem that we emit correct DWARF for registers
with DWARF numbers > 31. If you instead use readelf for such cases, it
will interpret the number of specified bytes as a DWARF expression. This
seems like a limitation in llvm-dwarfdump.

As suggested in D66746, a way forward would be to add an internal
variant of DW_OP_entry_value, DW_OP_LLVM_entry_value, whose operand
instead specifies the number of operations that the entry value covers,
and we then translate that into the byte size at the time of emission.

In this patch that internal operation is added. This patch keeps the
limitation that a entry value can only be applied to simple register
locations, but it will fix the issue with the size operand being
incorrect for DWARF numbers > 31.

Reviewers: aprantl, vsk, djtodoro, NikolaPrica

Reviewed By: aprantl

Subscribers: jyknight, fedor.sergeev, hiraditya, llvm-commits

Tags: #debug-info, #llvm

Differential Revision: https://reviews.llvm.org/D67492

llvm-svn: 374881
2019-10-15 11:31:21 +00:00
Jorge Gorbe Moya b052331bd6 Revert "Dead Virtual Function Elimination"
This reverts commit 9f6a873268.

llvm-svn: 374844
2019-10-14 23:25:25 +00:00
DeForest Richards 22373c595e [Docs] Moves Control Flow Document to User Guides
Moves Control Flow document from Reference docs page to User guides page.

llvm-svn: 374733
2019-10-13 20:05:22 +00:00
Roman Lebedev 76cdcf25b8 [LoopIdiomRecognize] Recommit: BCmp loop idiom recognition
Summary:
This is a recommit, this originally landed in rL370454 but was
subsequently reverted in  rL370788 due to
https://bugs.llvm.org/show_bug.cgi?id=43206
The reduced testcase was added to bcmp-negative-tests.ll
as @pr43206_different_loops - we must ensure that the SCEV's
we got are both for the same loop we are currently investigating.

Original commit message:

@mclow.lists brought up this issue up in IRC.
It is a reasonably common problem to compare some two values for equality.
Those may be just some integers, strings or arrays of integers.

In C, there is `memcmp()`, `bcmp()` functions.
In C++, there exists `std::equal()` algorithm.
One can also write that function manually.

libstdc++'s `std::equal()` is specialized to directly call `memcmp()` for
various types, but not `std::byte` from C++2a. https://godbolt.org/z/mx2ejJ

libc++ does not do anything like that, it simply relies on simple C++'s
`operator==()`. https://godbolt.org/z/er0Zwf (GOOD!)

So likely, there exists a certain performance opportunities.
Let's compare performance of naive `std::equal()` (no `memcmp()`) with one that
is using `memcmp()` (in this case, compiled with modified compiler). {F8768213}

```
#include <algorithm>
#include <cmath>
#include <cstdint>
#include <iterator>
#include <limits>
#include <random>
#include <type_traits>
#include <utility>
#include <vector>

#include "benchmark/benchmark.h"

template <class T>
bool equal(T* a, T* a_end, T* b) noexcept {
  for (; a != a_end; ++a, ++b) {
    if (*a != *b) return false;
  }
  return true;
}

template <typename T>
std::vector<T> getVectorOfRandomNumbers(size_t count) {
  std::random_device rd;
  std::mt19937 gen(rd());
  std::uniform_int_distribution<T> dis(std::numeric_limits<T>::min(),
                                       std::numeric_limits<T>::max());
  std::vector<T> v;
  v.reserve(count);
  std::generate_n(std::back_inserter(v), count,
                  [&dis, &gen]() { return dis(gen); });
  assert(v.size() == count);
  return v;
}

struct Identical {
  template <typename T>
  static std::pair<std::vector<T>, std::vector<T>> Gen(size_t count) {
    auto Tmp = getVectorOfRandomNumbers<T>(count);
    return std::make_pair(Tmp, std::move(Tmp));
  }
};

struct InequalHalfway {
  template <typename T>
  static std::pair<std::vector<T>, std::vector<T>> Gen(size_t count) {
    auto V0 = getVectorOfRandomNumbers<T>(count);
    auto V1 = V0;
    V1[V1.size() / size_t(2)]++;  // just change the value.
    return std::make_pair(std::move(V0), std::move(V1));
  }
};

template <class T, class Gen>
void BM_bcmp(benchmark::State& state) {
  const size_t Length = state.range(0);

  const std::pair<std::vector<T>, std::vector<T>> Data =
      Gen::template Gen<T>(Length);
  const std::vector<T>& a = Data.first;
  const std::vector<T>& b = Data.second;
  assert(a.size() == Length && b.size() == a.size());

  benchmark::ClobberMemory();
  benchmark::DoNotOptimize(a);
  benchmark::DoNotOptimize(a.data());
  benchmark::DoNotOptimize(b);
  benchmark::DoNotOptimize(b.data());

  for (auto _ : state) {
    const bool is_equal = equal(a.data(), a.data() + a.size(), b.data());
    benchmark::DoNotOptimize(is_equal);
  }
  state.SetComplexityN(Length);
  state.counters["eltcnt"] =
      benchmark::Counter(Length, benchmark::Counter::kIsIterationInvariant);
  state.counters["eltcnt/sec"] =
      benchmark::Counter(Length, benchmark::Counter::kIsIterationInvariantRate);
  const size_t BytesRead = 2 * sizeof(T) * Length;
  state.counters["bytes_read/iteration"] =
      benchmark::Counter(BytesRead, benchmark::Counter::kDefaults,
                         benchmark::Counter::OneK::kIs1024);
  state.counters["bytes_read/sec"] = benchmark::Counter(
      BytesRead, benchmark::Counter::kIsIterationInvariantRate,
      benchmark::Counter::OneK::kIs1024);
}

template <typename T>
static void CustomArguments(benchmark::internal::Benchmark* b) {
  const size_t L2SizeBytes = []() {
    for (const benchmark::CPUInfo::CacheInfo& I :
         benchmark::CPUInfo::Get().caches) {
      if (I.level == 2) return I.size;
    }
    return 0;
  }();
  // What is the largest range we can check to always fit within given L2 cache?
  const size_t MaxLen = L2SizeBytes / /*total bufs*/ 2 /
                        /*maximal elt size*/ sizeof(T) / /*safety margin*/ 2;
  b->RangeMultiplier(2)->Range(1, MaxLen)->Complexity(benchmark::oN);
}

BENCHMARK_TEMPLATE(BM_bcmp, uint8_t, Identical)
    ->Apply(CustomArguments<uint8_t>);
BENCHMARK_TEMPLATE(BM_bcmp, uint16_t, Identical)
    ->Apply(CustomArguments<uint16_t>);
BENCHMARK_TEMPLATE(BM_bcmp, uint32_t, Identical)
    ->Apply(CustomArguments<uint32_t>);
BENCHMARK_TEMPLATE(BM_bcmp, uint64_t, Identical)
    ->Apply(CustomArguments<uint64_t>);

BENCHMARK_TEMPLATE(BM_bcmp, uint8_t, InequalHalfway)
    ->Apply(CustomArguments<uint8_t>);
BENCHMARK_TEMPLATE(BM_bcmp, uint16_t, InequalHalfway)
    ->Apply(CustomArguments<uint16_t>);
BENCHMARK_TEMPLATE(BM_bcmp, uint32_t, InequalHalfway)
    ->Apply(CustomArguments<uint32_t>);
BENCHMARK_TEMPLATE(BM_bcmp, uint64_t, InequalHalfway)
    ->Apply(CustomArguments<uint64_t>);
```
{F8768210}
```
$ ~/src/googlebenchmark/tools/compare.py --no-utest benchmarks build-{old,new}/test/llvm-bcmp-bench
RUNNING: build-old/test/llvm-bcmp-bench --benchmark_out=/tmp/tmpb6PEUx
2019-04-25 21:17:11
Running build-old/test/llvm-bcmp-bench
Run on (8 X 4000 MHz CPU s)
CPU Caches:
  L1 Data 16K (x8)
  L1 Instruction 64K (x4)
  L2 Unified 2048K (x4)
  L3 Unified 8192K (x1)
Load Average: 0.65, 3.90, 4.14
---------------------------------------------------------------------------------------------------
Benchmark                                         Time             CPU   Iterations UserCounters...
---------------------------------------------------------------------------------------------------
<...>
BM_bcmp<uint8_t, Identical>/512000           432131 ns       432101 ns         1613 bytes_read/iteration=1000k bytes_read/sec=2.20706G/s eltcnt=825.856M eltcnt/sec=1.18491G/s
BM_bcmp<uint8_t, Identical>_BigO               0.86 N          0.86 N
BM_bcmp<uint8_t, Identical>_RMS                   8 %             8 %
<...>
BM_bcmp<uint16_t, Identical>/256000          161408 ns       161409 ns         4027 bytes_read/iteration=1000k bytes_read/sec=5.90843G/s eltcnt=1030.91M eltcnt/sec=1.58603G/s
BM_bcmp<uint16_t, Identical>_BigO              0.67 N          0.67 N
BM_bcmp<uint16_t, Identical>_RMS                 25 %            25 %
<...>
BM_bcmp<uint32_t, Identical>/128000           81497 ns        81488 ns         8415 bytes_read/iteration=1000k bytes_read/sec=11.7032G/s eltcnt=1077.12M eltcnt/sec=1.57078G/s
BM_bcmp<uint32_t, Identical>_BigO              0.71 N          0.71 N
BM_bcmp<uint32_t, Identical>_RMS                 42 %            42 %
<...>
BM_bcmp<uint64_t, Identical>/64000            50138 ns        50138 ns        10909 bytes_read/iteration=1000k bytes_read/sec=19.0209G/s eltcnt=698.176M eltcnt/sec=1.27647G/s
BM_bcmp<uint64_t, Identical>_BigO              0.84 N          0.84 N
BM_bcmp<uint64_t, Identical>_RMS                 27 %            27 %
<...>
BM_bcmp<uint8_t, InequalHalfway>/512000      192405 ns       192392 ns         3638 bytes_read/iteration=1000k bytes_read/sec=4.95694G/s eltcnt=1.86266G eltcnt/sec=2.66124G/s
BM_bcmp<uint8_t, InequalHalfway>_BigO          0.38 N          0.38 N
BM_bcmp<uint8_t, InequalHalfway>_RMS              3 %             3 %
<...>
BM_bcmp<uint16_t, InequalHalfway>/256000     127858 ns       127860 ns         5477 bytes_read/iteration=1000k bytes_read/sec=7.45873G/s eltcnt=1.40211G eltcnt/sec=2.00219G/s
BM_bcmp<uint16_t, InequalHalfway>_BigO         0.50 N          0.50 N
BM_bcmp<uint16_t, InequalHalfway>_RMS             0 %             0 %
<...>
BM_bcmp<uint32_t, InequalHalfway>/128000      49140 ns        49140 ns        14281 bytes_read/iteration=1000k bytes_read/sec=19.4072G/s eltcnt=1.82797G eltcnt/sec=2.60478G/s
BM_bcmp<uint32_t, InequalHalfway>_BigO         0.40 N          0.40 N
BM_bcmp<uint32_t, InequalHalfway>_RMS            18 %            18 %
<...>
BM_bcmp<uint64_t, InequalHalfway>/64000       32101 ns        32099 ns        21786 bytes_read/iteration=1000k bytes_read/sec=29.7101G/s eltcnt=1.3943G eltcnt/sec=1.99381G/s
BM_bcmp<uint64_t, InequalHalfway>_BigO         0.50 N          0.50 N
BM_bcmp<uint64_t, InequalHalfway>_RMS             1 %             1 %
RUNNING: build-new/test/llvm-bcmp-bench --benchmark_out=/tmp/tmpQ46PP0
2019-04-25 21:19:29
Running build-new/test/llvm-bcmp-bench
Run on (8 X 4000 MHz CPU s)
CPU Caches:
  L1 Data 16K (x8)
  L1 Instruction 64K (x4)
  L2 Unified 2048K (x4)
  L3 Unified 8192K (x1)
Load Average: 1.01, 2.85, 3.71
---------------------------------------------------------------------------------------------------
Benchmark                                         Time             CPU   Iterations UserCounters...
---------------------------------------------------------------------------------------------------
<...>
BM_bcmp<uint8_t, Identical>/512000            18593 ns        18590 ns        37565 bytes_read/iteration=1000k bytes_read/sec=51.2991G/s eltcnt=19.2333G eltcnt/sec=27.541G/s
BM_bcmp<uint8_t, Identical>_BigO               0.04 N          0.04 N
BM_bcmp<uint8_t, Identical>_RMS                  37 %            37 %
<...>
BM_bcmp<uint16_t, Identical>/256000           18950 ns        18948 ns        37223 bytes_read/iteration=1000k bytes_read/sec=50.3324G/s eltcnt=9.52909G eltcnt/sec=13.511G/s
BM_bcmp<uint16_t, Identical>_BigO              0.08 N          0.08 N
BM_bcmp<uint16_t, Identical>_RMS                 34 %            34 %
<...>
BM_bcmp<uint32_t, Identical>/128000           18627 ns        18627 ns        37895 bytes_read/iteration=1000k bytes_read/sec=51.198G/s eltcnt=4.85056G eltcnt/sec=6.87168G/s
BM_bcmp<uint32_t, Identical>_BigO              0.16 N          0.16 N
BM_bcmp<uint32_t, Identical>_RMS                 35 %            35 %
<...>
BM_bcmp<uint64_t, Identical>/64000            18855 ns        18855 ns        37458 bytes_read/iteration=1000k bytes_read/sec=50.5791G/s eltcnt=2.39731G eltcnt/sec=3.3943G/s
BM_bcmp<uint64_t, Identical>_BigO              0.32 N          0.32 N
BM_bcmp<uint64_t, Identical>_RMS                 33 %            33 %
<...>
BM_bcmp<uint8_t, InequalHalfway>/512000        9570 ns         9569 ns        73500 bytes_read/iteration=1000k bytes_read/sec=99.6601G/s eltcnt=37.632G eltcnt/sec=53.5046G/s
BM_bcmp<uint8_t, InequalHalfway>_BigO          0.02 N          0.02 N
BM_bcmp<uint8_t, InequalHalfway>_RMS             29 %            29 %
<...>
BM_bcmp<uint16_t, InequalHalfway>/256000       9547 ns         9547 ns        74343 bytes_read/iteration=1000k bytes_read/sec=99.8971G/s eltcnt=19.0318G eltcnt/sec=26.8159G/s
BM_bcmp<uint16_t, InequalHalfway>_BigO         0.04 N          0.04 N
BM_bcmp<uint16_t, InequalHalfway>_RMS            29 %            29 %
<...>
BM_bcmp<uint32_t, InequalHalfway>/128000       9396 ns         9394 ns        73521 bytes_read/iteration=1000k bytes_read/sec=101.518G/s eltcnt=9.41069G eltcnt/sec=13.6255G/s
BM_bcmp<uint32_t, InequalHalfway>_BigO         0.08 N          0.08 N
BM_bcmp<uint32_t, InequalHalfway>_RMS            30 %            30 %
<...>
BM_bcmp<uint64_t, InequalHalfway>/64000        9499 ns         9498 ns        73802 bytes_read/iteration=1000k bytes_read/sec=100.405G/s eltcnt=4.72333G eltcnt/sec=6.73808G/s
BM_bcmp<uint64_t, InequalHalfway>_BigO         0.16 N          0.16 N
BM_bcmp<uint64_t, InequalHalfway>_RMS            28 %            28 %
Comparing build-old/test/llvm-bcmp-bench to build-new/test/llvm-bcmp-bench
Benchmark                                                  Time             CPU      Time Old      Time New       CPU Old       CPU New
---------------------------------------------------------------------------------------------------------------------------------------
<...>
BM_bcmp<uint8_t, Identical>/512000                      -0.9570         -0.9570        432131         18593        432101         18590
<...>
BM_bcmp<uint16_t, Identical>/256000                     -0.8826         -0.8826        161408         18950        161409         18948
<...>
BM_bcmp<uint32_t, Identical>/128000                     -0.7714         -0.7714         81497         18627         81488         18627
<...>
BM_bcmp<uint64_t, Identical>/64000                      -0.6239         -0.6239         50138         18855         50138         18855
<...>
BM_bcmp<uint8_t, InequalHalfway>/512000                 -0.9503         -0.9503        192405          9570        192392          9569
<...>
BM_bcmp<uint16_t, InequalHalfway>/256000                -0.9253         -0.9253        127858          9547        127860          9547
<...>
BM_bcmp<uint32_t, InequalHalfway>/128000                -0.8088         -0.8088         49140          9396         49140          9394
<...>
BM_bcmp<uint64_t, InequalHalfway>/64000                 -0.7041         -0.7041         32101          9499         32099          9498
```

What can we tell from the benchmark?
* Performance of naive equality check somewhat improves with element size,
  maxing out at eltcnt/sec=1.58603G/s for uint16_t, or bytes_read/sec=19.0209G/s
  for uint64_t. I think, that instability implies performance problems.
* Performance of `memcmp()`-aware benchmark always maxes out at around
  bytes_read/sec=51.2991G/s for every type. That is 2.6x the throughput of the
  naive variant!
* eltcnt/sec metric for the `memcmp()`-aware benchmark maxes out at
  eltcnt/sec=27.541G/s for uint8_t (was: eltcnt/sec=1.18491G/s, so 24x) and
  linearly decreases with element size.
  For uint64_t, it's ~4x+ the elements/second.
* The call obvious is more pricey than the loop, with small element count.
  As it can be seen from the full output {F8768210}, the `memcmp()` is almost
  universally worse, independent of the element size (and thus buffer size) when
  element count is less than 8.

So all in all, bcmp idiom does indeed pose untapped performance headroom.
This diff does implement said idiom recognition. I think a reasonable test
coverage is present, but do tell if there is anything obvious missing.

Now, quality. This does succeed to build and pass the test-suite, at least
without any non-bundled elements. {F8768216} {F8768217}
This transform fires 91 times:
```
$ /build/test-suite/utils/compare.py -m loop-idiom.NumBCmp result-new.json
Tests: 1149
Metric: loop-idiom.NumBCmp

Program                                         result-new

MultiSourc...Benchmarks/7zip/7zip-benchmark    79.00
MultiSource/Applications/d/make_dparser         3.00
SingleSource/UnitTests/vla                      2.00
MultiSource/Applications/Burg/burg              1.00
MultiSourc.../Applications/JM/lencod/lencod     1.00
MultiSource/Applications/lemon/lemon            1.00
MultiSource/Benchmarks/Bullet/bullet            1.00
MultiSourc...e/Benchmarks/MallocBench/gs/gs     1.00
MultiSourc...gs-C/TimberWolfMC/timberwolfmc     1.00
MultiSourc...Prolangs-C/simulator/simulator     1.00
```
The size changes are:
I'm not sure what's going on with SingleSource/UnitTests/vla.test yet, did not look.
```
$ /build/test-suite/utils/compare.py -m size..text result-{old,new}.json --filter-hash
Tests: 1149
Same hash: 907 (filtered out)
Remaining: 242
Metric: size..text

Program                                        result-old result-new diff
test-suite...ingleSource/UnitTests/vla.test   753.00     833.00     10.6%
test-suite...marks/7zip/7zip-benchmark.test   1001697.00 966657.00  -3.5%
test-suite...ngs-C/simulator/simulator.test   32369.00   32321.00   -0.1%
test-suite...plications/d/make_dparser.test   89585.00   89505.00   -0.1%
test-suite...ce/Applications/Burg/burg.test   40817.00   40785.00   -0.1%
test-suite.../Applications/lemon/lemon.test   47281.00   47249.00   -0.1%
test-suite...TimberWolfMC/timberwolfmc.test   250065.00  250113.00   0.0%
test-suite...chmarks/MallocBench/gs/gs.test   149889.00  149873.00  -0.0%
test-suite...ications/JM/lencod/lencod.test   769585.00  769569.00  -0.0%
test-suite.../Benchmarks/Bullet/bullet.test   770049.00  770049.00   0.0%
test-suite...HMARK_ANISTROPIC_DIFFUSION/128    NaN        NaN        nan%
test-suite...HMARK_ANISTROPIC_DIFFUSION/256    NaN        NaN        nan%
test-suite...CHMARK_ANISTROPIC_DIFFUSION/64    NaN        NaN        nan%
test-suite...CHMARK_ANISTROPIC_DIFFUSION/32    NaN        NaN        nan%
test-suite...ENCHMARK_BILATERAL_FILTER/64/4    NaN        NaN        nan%
Geomean difference                                                   nan%
         result-old    result-new       diff
count  1.000000e+01  10.00000      10.000000
mean   3.152090e+05  311695.40000  0.006749
std    3.790398e+05  372091.42232  0.036605
min    7.530000e+02  833.00000    -0.034981
25%    4.243300e+04  42401.00000  -0.000866
50%    1.197370e+05  119689.00000 -0.000392
75%    6.397050e+05  639705.00000 -0.000005
max    1.001697e+06  966657.00000  0.106242
```

I don't have timings though.

And now to the code. The basic idea is to completely replace the whole loop.
If we can't fully kill it, don't transform.
I have left one or two comments in the code, so hopefully it can be understood.

Also, there is a few TODO's that i have left for follow-ups:
* widening of `memcmp()`/`bcmp()`
* step smaller than the comparison size
* Metadata propagation
* more than two blocks as long as there is still a single backedge?
* ???

Reviewers: reames, fhahn, mkazantsev, chandlerc, craig.topper, courbet

Reviewed By: courbet

Subscribers: miyuki, hiraditya, xbolva00, nikic, jfb, gchatelet, courbet, llvm-commits, mclow.lists

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D61144

llvm-svn: 374662
2019-10-12 15:35:32 +00:00
Oliver Stannard 9f6a873268 Dead Virtual Function Elimination
Currently, it is hard for the compiler to remove unused C++ virtual
functions, because they are all referenced from vtables, which are referenced
by constructors. This means that if the constructor is called from any live
code, then we keep every virtual function in the final link, even if there
are no call sites which can use it.

This patch allows unused virtual functions to be removed during LTO (and
regular compilation in limited circumstances) by using type metadata to match
virtual function call sites to the vtable slots they might load from. This
information can then be used in the global dead code elimination pass instead
of the references from vtables to virtual functions, to more accurately
determine which functions are reachable.

To make this transformation safe, I have changed clang's code-generation to
always load virtual function pointers using the llvm.type.checked.load
intrinsic, instead of regular load instructions. I originally tried writing
this using clang's existing code-generation, which uses the llvm.type.test
and llvm.assume intrinsics after doing a normal load. However, it is possible
for optimisations to obscure the relationship between the GEP, load and
llvm.type.test, causing GlobalDCE to fail to find virtual function call
sites.

The existing linkage and visibility types don't accurately describe the scope
in which a virtual call could be made which uses a given vtable. This is
wider than the visibility of the type itself, because a virtual function call
could be made using a more-visible base class. I've added a new
!vcall_visibility metadata type to represent this, described in
TypeMetadata.rst. The internalization pass and libLTO have been updated to
change this metadata when linking is performed.

This doesn't currently work with ThinLTO, because it needs to see every call
to llvm.type.checked.load in the linkage unit. It might be possible to
extend this optimisation to be able to use the ThinLTO summary, as was done
for devirtualization, but until then that combination is rejected in the
clang driver.

To test this, I've written a fuzzer which generates random C++ programs with
complex class inheritance graphs, and virtual functions called through object
and function pointers of different types. The programs are spread across
multiple translation units and DSOs to test the different visibility
restrictions.

I've also tried doing bootstrap builds of LLVM to test this. This isn't
ideal, because only classes in anonymous namespaces can be optimised with
-fvisibility=default, and some parts of LLVM (plugins and bugpoint) do not
work correctly with -fvisibility=hidden. However, there are only 12 test
failures when building with -fvisibility=hidden (and an unmodified compiler),
and this change does not cause any new failures for either value of
-fvisibility.

On the 7 C++ sub-benchmarks of SPEC2006, this gives a geomean code-size
reduction of ~6%, over a baseline compiled with "-O2 -flto
-fvisibility=hidden -fwhole-program-vtables". The best cases are reductions
of ~14% in 450.soplex and 483.xalancbmk, and there are no code size
increases.

I've also run this on a set of 8 mbed-os examples compiled for Armv7M, which
show a geomean size reduction of ~3%, again with no size increases.

I had hoped that this would have no effect on performance, which would allow
it to awlays be enabled (when using -fwhole-program-vtables). However, the
changes in clang to use the llvm.type.checked.load intrinsic are causing ~1%
performance regression in the C++ parts of SPEC2006. It should be possible to
recover some of this perf loss by teaching optimisations about the
llvm.type.checked.load intrinsic, which would make it worth turning this on
by default (though it's still dependent on -fwhole-program-vtables).

Differential revision: https://reviews.llvm.org/D63932

llvm-svn: 374539
2019-10-11 11:59:55 +00:00
Kai Nacke 5b5b2fd2b8 [FileCheck] Implement --ignore-case option.
The FileCheck utility is enhanced to support a `--ignore-case`
option. This is useful in cases where the output of Unix tools
differs in case (e.g. case not specified by Posix).

Reviewers: Bigcheese, jakehehrlich, rupprecht, espindola, alexshap, jhenderson, MaskRay

Differential Revision: https://reviews.llvm.org/D68146

llvm-svn: 374538
2019-10-11 11:59:14 +00:00
Tom Stellard 97578b14fc docs/DeveloperPolicy: Add instructions for requesting GitHub commit access
Subscribers: mehdi_amini, jtony, xbolva00, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66840

llvm-svn: 374474
2019-10-10 23:36:06 +00:00
Julian Lettner b858895c85 [lit] Bring back `--threads` option alias
Bring back `--threads` option which was lost in the move of the
command line argument parsing code to cl_arguments.py.  Update docs
since `--workers` is preferred.

llvm-svn: 374432
2019-10-10 19:43:57 +00:00
Jinsong Ji 26cd5c9370 [PowerPC][docs] Update IBM official docs in Compiler Writers Info page
Summary:
Just realized that most of the links in this page are deprecated.
So update some important reference here:
* adding PowerISA 3.0B/2.7B
* adding P8/P9 User Manual
* ELFv2 ABI and errata

Move deprecated ones into "Other documents..".

Reviewers: #powerpc, hfinkel, nemanjai

Reviewed By: hfinkel

Subscribers: shchenz, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68817

llvm-svn: 374428
2019-10-10 19:25:30 +00:00
Roman Lebedev a5e65c1cf7 [MCA] Show aggregate over Average Wait times for the whole snippet (PR43219)
Summary:
As disscused in https://bugs.llvm.org/show_bug.cgi?id=43219,
i believe it may be somewhat useful to show //some// aggregates
over all the sea of statistics provided.

Example:
```
Average Wait times (based on the timeline view):
[0]: Executions
[1]: Average time spent waiting in a scheduler's queue
[2]: Average time spent waiting in a scheduler's queue while ready
[3]: Average time elapsed from WB until retire stage

      [0]    [1]    [2]    [3]
0.     3     1.0    1.0    4.7       vmulps     %xmm0, %xmm1, %xmm2
1.     3     2.7    0.0    2.3       vhaddps    %xmm2, %xmm2, %xmm3
2.     3     6.0    0.0    0.0       vhaddps    %xmm3, %xmm3, %xmm4
       3     3.2    0.3    2.3       <total>
```
I.e. we average the averages.

Reviewers: andreadb, mattd, RKSimon

Reviewed By: andreadb

Subscribers: gbedwell, arphaman, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68714

llvm-svn: 374361
2019-10-10 14:46:21 +00:00
Dmitri Gribenko d3aed7fc79 Revert "[FileCheck] Implement --ignore-case option."
This reverts commit r374339. It broke tests:
http://lab.llvm.org:8011/builders/clang-x86_64-debian-fast/builds/19066

llvm-svn: 374359
2019-10-10 14:27:14 +00:00
Kai Nacke dfd2b6f07f [FileCheck] Implement --ignore-case option.
The FileCheck utility is enhanced to support a `--ignore-case`
option. This is useful in cases where the output of Unix tools
differs in case (e.g. case not specified by Posix).

Reviewers: Bigcheese, jakehehrlich, rupprecht, espindola, alexshap, jhenderson, MaskRay

Differential Revision: https://reviews.llvm.org/D68146

llvm-svn: 374339
2019-10-10 13:15:41 +00:00
Roman Lebedev 536b0ee40a [UBSan][clang][compiler-rt] Applying non-zero offset to nullptr is undefined behaviour
Summary:
Quote from http://eel.is/c++draft/expr.add#4:
```
4     When an expression J that has integral type is added to or subtracted
      from an expression P of pointer type, the result has the type of P.
(4.1) If P evaluates to a null pointer value and J evaluates to 0,
      the result is a null pointer value.
(4.2) Otherwise, if P points to an array element i of an array object x with n
      elements ([dcl.array]), the expressions P + J and J + P
      (where J has the value j) point to the (possibly-hypothetical) array
      element i+j of x if 0≤i+j≤n and the expression P - J points to the
      (possibly-hypothetical) array element i−j of x if 0≤i−j≤n.
(4.3) Otherwise, the behavior is undefined.
```

Therefore, as per the standard, applying non-zero offset to `nullptr`
(or making non-`nullptr` a `nullptr`, by subtracting pointer's integral value
from the pointer itself) is undefined behavior. (*if* `nullptr` is not defined,
i.e. e.g. `-fno-delete-null-pointer-checks` was *not* specified.)

To make things more fun, in C (6.5.6p8), applying *any* offset to null pointer
is undefined, although Clang front-end pessimizes the code by not lowering
that info, so this UB is "harmless".

Since rL369789 (D66608 `[InstCombine] icmp eq/ne (gep inbounds P, Idx..), null -> icmp eq/ne P, null`)
LLVM middle-end uses those guarantees for transformations.
If the source contains such UB's, said code may now be miscompiled.
Such miscompilations were already observed:
* https://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20190826/687838.html
* https://github.com/google/filament/pull/1566

Surprisingly, UBSan does not catch those issues
... until now. This diff teaches UBSan about these UB's.

`getelementpointer inbounds` is a pretty frequent instruction,
so this does have a measurable impact on performance;
I've addressed most of the obvious missing folds (and thus decreased the performance impact by ~5%),
and then re-performed some performance measurements using my [[ https://github.com/darktable-org/rawspeed | RawSpeed ]] benchmark:
(all measurements done with LLVM ToT, the sanitizer never fired.)
* no sanitization vs. existing check: average `+21.62%` slowdown
* existing check vs. check after this patch: average `22.04%` slowdown
* no sanitization vs. this patch: average `48.42%` slowdown

Reviewers: vsk, filcab, rsmith, aaron.ballman, vitalybuka, rjmccall, #sanitizers

Reviewed By: rsmith

Subscribers: kristof.beyls, nickdesaulniers, nikic, ychen, dtzWill, xbolva00, dberris, arphaman, rupprecht, reames, regehr, llvm-commits, cfe-commits

Tags: #clang, #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D67122

llvm-svn: 374293
2019-10-10 09:25:02 +00:00
DeForest Richards edbb895b18 [Docs] Adds section for Additional Topics on Reference page
Adds a new section for Additional Topics on the Reference documentation page. Also moves Support Library topic to User Guides page.

llvm-svn: 374230
2019-10-09 21:09:09 +00:00
DeForest Richards 02d264a547 [Docs] Adds Documentation links to sidebar
Adds links to Getting Started/Tutorials, User Guides, and Reference documentation pages to sidebar. Also adds a new section for LLVM IR on the Reference documentation page.

llvm-svn: 374214
2019-10-09 20:26:13 +00:00
DeForest Richards b7538c5140 [Docs] Fixes broken sphinx build - undefined label
Removes label ref pointing to non-existent subsystem docs page.

llvm-svn: 374128
2019-10-08 22:45:20 +00:00
Clement Courbet 2cd0f28959 [llvm-exegesis] Add options to SnippetGenerator.
Summary:
This adds a `-max-configs-per-opcode` option to limit the number of
configs per opcode.

Reviewers: gchatelet

Subscribers: tschuett, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68642

llvm-svn: 374054
2019-10-08 14:30:24 +00:00
Kevin P. Neal c91f1992a6 Nope, I'm wrong. It looks like someone else removed these on purpose and
it just happened to break the bot right when I did my push. So I'm undoing
this mornings incorrect push. I've also kicked off an email to hopefully
get the bot fixed the correct way.

llvm-svn: 374049
2019-10-08 14:10:26 +00:00
Kevin P. Neal 0929e5eca2 Restore documentation that 'svn update' unexpectedly yanked out from under me.
llvm-svn: 374045
2019-10-08 13:38:42 +00:00
Joerg Sonnenberger 2b9f0b064b Fix the spelling of my name.
llvm-svn: 373980
2019-10-07 22:55:42 +00:00
Reid Kleckner f9b67b810e [X86] Add new calling convention that guarantees tail call optimization
When the target option GuaranteedTailCallOpt is specified, calls with
the fastcc calling convention will be transformed into tail calls if
they are in tail position. This diff adds a new calling convention,
tailcc, currently supported only on X86, which behaves the same way as
fastcc, except that the GuaranteedTailCallOpt flag does not need to
enabled in order to enable tail call optimization.

Patch by Dwight Guth <dwight.guth@runtimeverification.com>!

Reviewed By: lebedev.ri, paquette, rnk

Differential Revision: https://reviews.llvm.org/D67855

llvm-svn: 373976
2019-10-07 22:28:58 +00:00
Kevin P. Neal 9f4de84eb0 Fix another sphinx warning.
Differential Revision:	https://reviews.llvm.org/D64746

llvm-svn: 373909
2019-10-07 14:14:46 +00:00
Kevin P. Neal a6fc72fba9 Fix sphinx warnings.
Differential Revision:	https://reviews.llvm.org/D64746

llvm-svn: 373902
2019-10-07 13:39:56 +00:00
Kevin P. Neal 1c3d19c82d [FPEnv] Add constrained intrinsics for lrint and lround
Earlier in the year intrinsics for lrint, llrint, lround and llround were
added to llvm. The constrained versions are now implemented here.

Reviewed by:	andrew.w.kaylor, craig.topper, cameron.mcinally
Approved by:	craig.topper
Differential Revision:	https://reviews.llvm.org/D64746

llvm-svn: 373900
2019-10-07 13:20:00 +00:00
Djordje Todorovic 0c56f425a0 [llvm-locstats] Fix a typo in the documentation; NFC
llvm-svn: 373880
2019-10-07 07:31:49 +00:00
DeForest Richards 38d16c15b7 [Docs] Removes Subsystem Documentation page
Removes Subsystem Documentation page. Also moves existing topics on Subsystem Documentation page to User Guides and Reference pages.

llvm-svn: 373872
2019-10-06 22:49:22 +00:00
DeForest Richards de0e3aac2a [Docs] Removes Programming Documentation page
Removes Programming Documentation page. Also moves existing topics on Programming Documentation page to User Guides and Reference pages. 

llvm-svn: 373856
2019-10-06 16:10:11 +00:00
DeForest Richards 6d19651410 [Docs] Adds new Getting Started/Tutorials page
Adds a new page for Getting Started/Tutorials topics. Also updates existing topic categories on the User Guides and Reference pages.

llvm-svn: 373854
2019-10-06 15:36:37 +00:00
Sylvestre Ledru 68eef2bcd0 Update the FAQ: remove stuff related to the previous license +
update info about the portability of LLVM.

llvm-svn: 373576
2019-10-03 09:43:54 +00:00
Fangrui Song 671fb34358 [llvm-objcopy] Add --set-section-alignment
Fixes PR43181. This option was recently added to GNU objcopy (binutils
PR24942).

`llvm-objcopy -I binary -O elf64-x86-64 --set-section-alignment .data=8` can set the alignment of .data.

Reviewed By: grimar, jhenderson, rupprecht

Differential Revision: https://reviews.llvm.org/D67656

llvm-svn: 373461
2019-10-02 12:41:25 +00:00
Djordje Todorovic 2ef18fb41a Reland "[utils] Implement the llvm-locstats tool"
The tool reports verbose output for the DWARF debug location coverage.
The llvm-locstats for each variable or formal parameter DIE computes what
percentage from the code section bytes, where it is in scope, it has
location description. The line 0 shows the number (and the percentage) of
DIEs with no location information, but the line 100 shows the number (and
the percentage) of DIEs where there is location information in all code
section bytes (where the variable or parameter is in the scope). The line
50..59 shows the number (and the percentage) of DIEs where the location
information is in between 50 and 59 percentage of its scope covered.

Differential Revision: https://reviews.llvm.org/D66526

The cause of the test failure was resolved.

llvm-svn: 373427
2019-10-02 07:00:01 +00:00
Vedant Kumar a1e7efaaa8 [ReleaseProcess] Document requirement to set MACOSX_DEPLOYMENT_TARGET
llvm-svn: 373356
2019-10-01 17:10:45 +00:00
Djordje Todorovic 372048e908 Revert "Reland "[utils] Implement the llvm-locstats tool""
This reverts commit rL373317 due to test failure on the
clang-s390x-linux build bot.

llvm-svn: 373336
2019-10-01 13:21:15 +00:00
Djordje Todorovic 6d7f7e6792 Reland "[utils] Implement the llvm-locstats tool"
The tool reports verbose output for the DWARF debug location coverage.
The llvm-locstats for each variable or formal parameter DIE computes what
percentage from the code section bytes, where it is in scope, it has
location description. The line 0 shows the number (and the percentage) of
DIEs with no location information, but the line 100 shows the number (and
the percentage) of DIEs where there is location information in all code
section bytes (where the variable or parameter is in the scope). The line
50..59 shows the number (and the percentage) of DIEs where the location
information is in between 50 and 59 percentage of its scope covered.

Differential Revision: https://reviews.llvm.org/D66526

llvm-svn: 373317
2019-10-01 09:59:15 +00:00
Fangrui Song 2d92c8844e [llvm-readobj/llvm-readelf] Delete --arm-attributes (alias for --arch-specific)
D68110 added --arch-specific (supported by GNU readelf) and made
--arm-attributes an alias for it. The tests were later migrated to use
--arch-specific.

Note, llvm-readelf --arch-specific currently just uses llvm-readobj
style output for ARM attributes. The readelf-style output is not
implemented.

Reviewed By: compnerd, kongyi, rupprecht

Differential Revision: https://reviews.llvm.org/D68196

llvm-svn: 373291
2019-10-01 01:31:15 +00:00
Pablo Barrio ffac4e8603 Fix doc for t inline asm constraints for ARM/Thumb
Summary: The constraint goes up to regs d15 and q7, not d16 and q8.

Subscribers: kristof.beyls, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68090

llvm-svn: 373228
2019-09-30 16:55:10 +00:00
Kevin P. Neal 71c5b38acd Fix breakage of sphinx builders. Sorry for leaving this broken over the
weekend!

llvm-svn: 373215
2019-09-30 14:51:59 +00:00
Djordje Todorovic 8180f3b1cc Revert "Reland "[utils] Implement the llvm-locstats tool""
This reverts commit rL373183.

llvm-svn: 373200
2019-09-30 11:19:11 +00:00
Djordje Todorovic 0f30960619 Reland "[utils] Implement the llvm-locstats tool"
The tool reports verbose output for the DWARF debug location coverage.
The llvm-locstats for each variable or formal parameter DIE computes what
percentage from the code section bytes, where it is in scope, it has
location description. The line 0 shows the number (and the percentage) of
DIEs with no location information, but the line 100 shows the number (and
the percentage) of DIEs where there is location information in all code
section bytes (where the variable or parameter is in the scope). The line
50..59 shows the number (and the percentage) of DIEs where the location
information is in between 50 and 59 percentage of its scope covered.

Differential Revision: https://reviews.llvm.org/D66526

llvm-svn: 373183
2019-09-30 07:35:17 +00:00
DeForest Richards eb78dea4cc [Docs] Moves article links to new pages
Moves existing article links on the Programming, Subsystem, and Reference documentation pages to new locations. Also moves Github Repository and Publications links to the sidebar.

llvm-svn: 373169
2019-09-29 15:31:52 +00:00
DeForest Richards ac5969933a [Docs] Adds sections for Command Line and LibFuzzer articles
Adds sections for Command Line and Libfuzzer articles on Programming Documentation page.

llvm-svn: 373158
2019-09-29 02:16:38 +00:00
DeForest Richards 2605f8c461 [Docs] Adds new section to User Guides page
Adds a section to the User Guides page for articles related to building, packaging, and distributing LLVM. Includes sub-sections for CMake, Clang, and Docker.

llvm-svn: 373113
2019-09-27 19:12:00 +00:00
Kevin P. Neal 875d20bcde Document requirement of function attributes with constrained floating
point.

Reviewed by:    andrew.w.kaylor, uweigand, efriedma
Approved by:    andrew.w.kaylor
Differential Revision:  https://reviews.llvm.org/D67839

llvm-svn: 373002
2019-09-26 17:50:25 +00:00
Nick Desaulniers 93d87260f1 [Verifier] add invariant check for callbr
Summary:
The list of indirect labels should ALWAYS have their blockaddresses as
argument operands to the callbr (but not necessarily the other way
around).  Add an invariant that checks this.

The verifier catches a bad test case that was added recently in r368478.
I think that was a simple mistake, and the test was made less strict in
regards to the precise addresses (as those weren't specifically the
point of the test).

This invariant will be used to find a reported bug.

Link: https://www.spinics.net/lists/arm-kernel/msg753473.html
Link: https://github.com/ClangBuiltLinux/linux/issues/649

Reviewers: craig.topper, void, chandlerc

Reviewed By: void

Subscribers: ychen, lebedev.ri, javed.absar, kristof.beyls, hiraditya, llvm-commits, srhines

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67196

llvm-svn: 372923
2019-09-25 22:28:27 +00:00
Florian Hahn 6b3749f696 [LangRef] Clarify absence of rounding guarantees for fmuladd.
During the review of D67434, it was recommended to make fmuladd's
behavior more explicit. D67434 depends on this interpretation.

Reviewers: efriedma, jfb, reames, scanon, lebedev.ri, spatel

Reviewed By: spatel

Differential Revision: https://reviews.llvm.org/D67552

llvm-svn: 372892
2019-09-25 16:09:24 +00:00
Sanjay Patel 6d4ea22e70 [IR] allow fast-math-flags on phi of FP values (2nd try)
The changes here are based on the corresponding diffs for allowing FMF on 'select':
D61917 <https://reviews.llvm.org/D61917>

As discussed there, we want to have fast-math-flags be a property of an FP value
because the alternative (having them on things like fcmp) leads to logical
inconsistency such as:
https://bugs.llvm.org/show_bug.cgi?id=38086

The earlier patch for select made almost no practical difference because most
unoptimized conditional code begins life as a phi (based on what I see in clang).
Similarly, I don't expect this patch to do much on its own either because
SimplifyCFG promptly drops the flags when converting to select on a minimal
example like:
https://bugs.llvm.org/show_bug.cgi?id=39535

But once we have this plumbing in place, we should be able to wire up the FMF
propagation and start solving cases like that.

The change to RecurrenceDescriptor::AddReductionVar() is required to prevent a
regression in a LoopVectorize test. We are intersecting the FMF of any
FPMathOperator there, so if a phi is not properly annotated, new math
instructions may not be either. Once we fix the propagation in SimplifyCFG, it
may be safe to remove that hack.

Differential Revision: https://reviews.llvm.org/D67564

llvm-svn: 372878
2019-09-25 14:35:02 +00:00
Sanjay Patel 2cec4b58f5 Revert [IR] allow fast-math-flags on phi of FP values
This reverts r372866 (git commit dec03223a9)

llvm-svn: 372868
2019-09-25 13:29:09 +00:00
Sanjay Patel dec03223a9 [IR] allow fast-math-flags on phi of FP values
The changes here are based on the corresponding diffs for allowing FMF on 'select':
D61917

As discussed there, we want to have fast-math-flags be a property of an FP value
because the alternative (having them on things like fcmp) leads to logical
inconsistency such as:
https://bugs.llvm.org/show_bug.cgi?id=38086

The earlier patch for select made almost no practical difference because most
unoptimized conditional code begins life as a phi (based on what I see in clang).
Similarly, I don't expect this patch to do much on its own either because
SimplifyCFG promptly drops the flags when converting to select on a minimal
example like:
https://bugs.llvm.org/show_bug.cgi?id=39535

But once we have this plumbing in place, we should be able to wire up the FMF
propagation and start solving cases like that.

The change to RecurrenceDescriptor::AddReductionVar() is required to prevent a
regression in a LoopVectorize test. We are intersecting the FMF of any
FPMathOperator there, so if a phi is not properly annotated, new math
instructions may not be either. Once we fix the propagation in SimplifyCFG, it
may be safe to remove that hack.

Differential Revision: https://reviews.llvm.org/D67564

llvm-svn: 372866
2019-09-25 13:14:12 +00:00
James Henderson 12e3099921 [docs][llvm-strings] Clarify "printable character" wording
The --bytes option uses the phrase "printable ASCII characters", but the
description section used simply "printable characters". To avoid any
confusion about locale impacts etc, this change adopts the former's
phrasing in both places. It also fixes a minor grammar issue in the
description.

Reviewed by: MaskRay

Differential Revision: https://reviews.llvm.org/D68016

llvm-svn: 372865
2019-09-25 13:09:17 +00:00
James Henderson 4dd9b2faec [docs][llvm-strip] Update llvm-strip doc to better match llvm-objcopy's
Main changes are mostly wording of some options, but this change also
fixes a switch reference so that a link is created and moves
--strip-sections into the ELF-specific area since it is only supported
for ELF currently.

llvm-svn: 372864
2019-09-25 13:09:12 +00:00
Dmitry Preobrazhensky b9683d3c53 [AMDGPU][MC][DOC] Updated AMD GPU assembler description.
Summary of changes:
- Updated to reflect recent changes in assembler;
- Minor bugfixing and improvements.

llvm-svn: 372857
2019-09-25 12:38:35 +00:00
DeForest Richards ccf6030f7a [Docs] Moves Reference docs to new page
Moves Reference docs to new page. Also adds a table of contents to Getting Involved page.

llvm-svn: 372796
2019-09-25 00:49:02 +00:00
James Henderson 1b103864ee [docs][llvm-strip][llvm-objcopy] Improve wording and fix highlighting
llvm-svn: 372754
2019-09-24 13:41:39 +00:00
James Henderson eefbc358eb [docs][llvm-size] Fix typo
llvm-svn: 372750
2019-09-24 13:14:22 +00:00
Djordje Todorovic ead96d73ac Revert "Reland "[utils] Implement the llvm-locstats tool""
This reverts commit rL372554.

llvm-svn: 372580
2019-09-23 11:04:11 +00:00
Djordje Todorovic 0e490ae0a9 Reland "[utils] Implement the llvm-locstats tool"
The tool reports verbose output for the DWARF debug location coverage.
The llvm-locstats for each variable or formal parameter DIE computes what
percentage from the code section bytes, where it is in scope, it has
location description. The line 0 shows the number (and the percentage) of
DIEs with no location information, but the line 100 shows the number (and
the percentage) of DIEs where there is location information in all code
section bytes (where the variable or parameter is in the scope). The line
50..59 shows the number (and the percentage) of DIEs where the location
information is in between 50 and 59 percentage of its scope covered.

Differential Revision: https://reviews.llvm.org/D66526

llvm-svn: 372554
2019-09-23 07:57:53 +00:00
DeForest Richards 4f86528fc1 [Docs] Updates sidebar links
Adds sidebar links to mailing lists, IRC, and meetups and social events.

llvm-svn: 372488
2019-09-21 21:05:20 +00:00
DeForest Richards c1b0873d42 [Docs] Adds new page for Getting Involved articles
Adds a new page for existing Getting Involved, Development Process, and Community Proposals articles. Also moves Mailing Lists, Meetups and social events, and IRC sections.

llvm-svn: 372487
2019-09-21 20:56:40 +00:00
DeForest Richards e75c6b6d48 [Docs] Bug fix for document not included in toctree
Fixes 'document not included in toctree' bug for FAQ and Lexicon topics.

llvm-svn: 372470
2019-09-21 14:29:19 +00:00
DeForest Richards 75d2c26921 [Docs] Updates sidebar links
Adds additional links to sidebar. Also removes Glossary and FAQ from LLVM Design & Overview section. (These links now reside on the sidebar.)

llvm-svn: 372469
2019-09-21 14:17:09 +00:00
DeForest Richards eacbe1cccc [Docs] Add a custom sidebar to doc pages
Adds a custom sidebar to LLVM docs. Sidebar includes links to How to submit a bug and FAQ topics, as well as a Show Source link and search box.

llvm-svn: 372432
2019-09-20 22:16:39 +00:00
DeForest Richards 01a3080960 [Docs] Move topics to new categories
This commit moves several topics to new categories. 

llvm-svn: 372428
2019-09-20 20:51:33 +00:00
Matt Morehouse 949a126438 [docs] Update structure-aware-fuzzing link.
The document has been moved to the google/fuzzing GitHub repo.

llvm-svn: 372423
2019-09-20 19:39:50 +00:00
Francesco Petrogalli be428513cb [docs] Remove training whitespaces. NFC
Subscribers: jfb, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67835

llvm-svn: 372399
2019-09-20 15:02:32 +00:00
David Tellenbach 0ecf34dde3 [NFC] Test commit, deleting some whitespace
llvm-svn: 372379
2019-09-20 09:43:31 +00:00
Francesco Petrogalli cde4f727ff [docs] Break long (>80) line. NFC
llvm-svn: 372326
2019-09-19 14:19:32 +00:00
DeForest Richards 8535ba6fa0 [Docs] Moves topics to new categories
This commit moves several topics to new categories. It also removes a few duplicate links in Subsystem Documentation.

llvm-svn: 372274
2019-09-18 23:04:31 +00:00
Bardia Mahjour db800c267d Data Dependence Graph Basics
Summary:
This is the first patch in a series of patches that will implement data dependence graph in LLVM. Many of the ideas used in this implementation are based on the following paper:
D. J. Kuck, R. H. Kuhn, D. A. Padua, B. Leasure, and M. Wolfe (1981). DEPENDENCE GRAPHS AND COMPILER OPTIMIZATIONS.
This patch contains support for a basic DDGs containing only atomic nodes (one node for each instruction). The edges are two fold: def-use edges and memory-dependence edges.
The implementation takes a list of basic-blocks and only considers dependencies among instructions in those basic blocks. Any dependencies coming into or going out of instructions that do not belong to those basic blocks are ignored.

The algorithm for building the graph involves the following steps in order:

  1. For each instruction in the range of basic blocks to consider, create an atomic node in the resulting graph.
  2. For each node in the graph establish def-use edges to/from other nodes in the graph.
  3. For each pair of nodes containing memory instruction(s) create memory edges between them. This part of the algorithm goes through the instructions in lexicographical order and creates edges in reverse order if the sink of the dependence occurs before the source of it.

Authored By: bmahjour

Reviewer: Meinersbur, fhahn, myhsu, xtian, dmgreen, kbarton, jdoerfert

Reviewed By: Meinersbur, fhahn, myhsu

Subscribers: ychen, arphaman, simoll, a.elovikov, mgorny, hiraditya, jfb, wuzish, llvm-commits, jsji, Whitney, etiotto

Tag: #llvm

Differential Revision: https://reviews.llvm.org/D65350

llvm-svn: 372238
2019-09-18 17:43:45 +00:00
Jinsong Ji 0c8e4a2e0d Reland "[docs][Bugpoint]Add notes about multiple crashes"
Fix the warning.
Bugpoint.rst:124:Mismatch: both interpreted text role prefix and
reference suffix.

Note that the line no here is wrong and misleading,
the problem is in line 128, not 124.

llvm-svn: 372181
2019-09-17 21:09:41 +00:00
Bardia Mahjour 6476d7cf0b Revert "Data Dependence Graph Basics"
This reverts commit c98ec60993, which broke the sphinx-docs build.

llvm-svn: 372168
2019-09-17 19:22:01 +00:00
Bardia Mahjour c98ec60993 Data Dependence Graph Basics
Summary:
This is the first patch in a series of patches that will implement data dependence graph in LLVM. Many of the ideas used in this implementation are based on the following paper:
D. J. Kuck, R. H. Kuhn, D. A. Padua, B. Leasure, and M. Wolfe (1981). DEPENDENCE GRAPHS AND COMPILER OPTIMIZATIONS.
This patch contains support for a basic DDGs containing only atomic nodes (one node for each instruction). The edges are two fold: def-use edges and memory-dependence edges.
The implementation takes a list of basic-blocks and only considers dependencies among instructions in those basic blocks. Any dependencies coming into or going out of instructions that do not belong to those basic blocks are ignored.

The algorithm for building the graph involves the following steps in order:

  1. For each instruction in the range of basic blocks to consider, create an atomic node in the resulting graph.
  2. For each node in the graph establish def-use edges to/from other nodes in the graph.
  3. For each pair of nodes containing memory instruction(s) create memory edges between them. This part of the algorithm goes through the instructions in lexicographical order and creates edges in reverse order if the sink of the dependence occurs before the source of it.

Authored By: bmahjour

Reviewer: Meinersbur, fhahn, myhsu, xtian, dmgreen, kbarton, jdoerfert

Reviewed By: Meinersbur, fhahn, myhsu

Subscribers: ychen, arphaman, simoll, a.elovikov, mgorny, hiraditya, jfb, wuzish, llvm-commits, jsji, Whitney, etiotto

Tag: #llvm

Differential Revision: https://reviews.llvm.org/D65350

llvm-svn: 372162
2019-09-17 18:55:44 +00:00
Jinsong Ji 6fce46a5f1 [docs][Bugpoint] Revert 5584ead50 a5aa3353
No sure why there are still warnings, revert while I investigate.

llvm-svn: 372161
2019-09-17 18:39:04 +00:00
Jinsong Ji 5584ead50e [docs][Bugpoint] Fix build break.
Bugpoint.rst:124: WARNING: Mismatch: both interpreted text role prefix
and reference suffix.

llvm-svn: 372160
2019-09-17 18:23:06 +00:00
Jinsong Ji a5aa335394 [docs][Bugpoint]Add notes about multiple crashes
Summary:
    When reducing case for a CodeGenCrash, bugpoint may generate a new
    reduced
    testcase that exposes/causes another crash or break something due to
    limitation.

    Bugpoint does not distiguish different crashes currently,
    so when this happens, bugpoint will go on reducing for the new crash,
    or just abort, we can't get the case reduced for the origial crash.

    An advice is added into usage doc to connect to recommend checking error
    message with scripts and `-compile-command`.

Reviewers: modocache, bogner, sebpop, reames, vsk, MatzeB

Reviewed By: vsk

Subscribers: mehdi_amini, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66832

llvm-svn: 372157
2019-09-17 18:10:09 +00:00
James Henderson 778a5e5734 [docs] Make --version text more correct
Follow-up to r371983. Referring to "this program" in the description of
the --version option in the documentation isn't exactly correct, because
the docs are not part of the program, and so "this program" doesn't
really refer to anything. This patch brings the other users of this
terminology into line with the new updates to llvm-size and
llvm-strings.

Reviewed by: alexshap, MaskRay

Differential Revision: https://reviews.llvm.org/D67618

llvm-svn: 372107
2019-09-17 11:43:42 +00:00
DeForest Richards 3b27f4c088 [Docs] Bug fix for docs homepage
Removes reference to non-existent Reference Documentation page.

llvm-svn: 372032
2019-09-16 20:29:56 +00:00
DeForest Richards e151cb7c63 [Docs] Adds Getting Started/Tutorials, Reference to LLVM docs homepage
Adds a section for Getting Started/Tutorials and Reference topics to the LLVM docs homepage.

llvm-svn: 372031
2019-09-16 20:19:32 +00:00
James Henderson 75b6279c5e [docs][llvm-strings] Write llvm-strings documentation
Previously we only had a stub document.

Reviewed by: MaskRay

Differential Revision: https://reviews.llvm.org/D67554

llvm-svn: 371984
2019-09-16 13:56:12 +00:00
James Henderson e8ed932683 [docs][llvm-size] Write llvm-size documentation
Previously we only had a stub document.

Reviewed by: serge-sans-paille, MaskRay

Differential Revision: https://reviews.llvm.org/D67555

llvm-svn: 371983
2019-09-16 13:20:37 +00:00
Kerry McLaughlin e55b3bf40e [SVE][Inline-Asm] Add constraints for SVE predicate registers
Summary:
Adds the following inline asm constraints for SVE:
  - Upl: One of the low eight SVE predicate registers, P0 to P7 inclusive
  - Upa: SVE predicate register with full range, P0 to P15

Reviewers: t.p.northover, sdesmalen, rovka, momchil.velikov, cameron.mcinally, greened, rengolin

Reviewed By: rovka

Subscribers: javed.absar, tschuett, rkruppe, psnobl, cfe-commits, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66524

llvm-svn: 371967
2019-09-16 09:45:27 +00:00
Fangrui Song 2f519d7072 [llvm-objcopy] Ignore -B --binary-architecture=
GNU objcopy documents that -B is only useful with architecture-less
input (i.e. "binary" or "ihex"). After D67144, -O defaults to -I, and
-B is essentially a NOP.

* If -O is binary/ihex, GNU objcopy ignores -B.
* If -O is elf*, -B provides the e_machine field in GNU objcopy.

So to convert a blob to an ELF, `-I binary -B i386:x86-64 -O elf64-x86-64` has to be specified.

`-I binary -B i386:x86-64 -O elf64-x86-64` creates an ELF with its
e_machine field set to EM_NONE in GNU objcopy, but a regular x86_64 ELF
in elftoolchain elfcopy. Follow the elftoolchain approach (ignoring -B)
to simplify code. Users that expect their command line portable should
specify -B.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D67215

llvm-svn: 371914
2019-09-14 01:36:31 +00:00
Michael Pozulp c45fd0cad4 [llvm-objcopy] Add support for response files in llvm-strip and llvm-objcopy
Summary: Addresses https://bugs.llvm.org/show_bug.cgi?id=42671

Reviewers: jhenderson, espindola, alexshap, rupprecht

Reviewed By: jhenderson

Subscribers: seiya, emaste, arichardson, jakehehrlich, MaskRay, abrachet, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65372

llvm-svn: 371911
2019-09-14 01:14:43 +00:00
DeForest Richards c6ffefd2d1 [Docs] Bug fix for reference to nonexistent document
This commit fixes a bug in which the toctree contained a reference to a non-existent document.

llvm-svn: 371889
2019-09-13 20:05:57 +00:00
Kevin P. Neal ed73d4aba8 [FPEnv] Document that constrained FP intrinsics cannot be mixed with non-constrained
Reviewed by:	andrew.w.kaylor, cameron.mcinally, uweigand
Approved by:	andrew.w.kaylor
Differential Revision:	https://reviews.llvm.org/D67360

llvm-svn: 371888
2019-09-13 19:36:19 +00:00
James Henderson a2497b43e3 [docs][llvm-readelf][llvm-readobj] Improve --stack-sizes documentation
llvm-readobj's document was missing --stack-sizes entirely from its
document, so this patch adds it. It also adds a note to the llvm-readelf
description that the switch is only implemented for GNU style output
currently. For reference, --stack-sizes was added in r367942.

Reviewed by: MaskRay

Differential Revision: https://reviews.llvm.org/D67548

llvm-svn: 371862
2019-09-13 15:01:39 +00:00
Nico Weber bb69208df8 Fix a few spellos in docs.
(Trying to debug an incremental build thing on a bot...)

llvm-svn: 371860
2019-09-13 14:58:24 +00:00
James Henderson 818e5c9503 [docs][llvm-objcopy][llvm-strip] Improve --strip-unneeded description
Behaviour was recently added to this switch to strip debug sections too.
See r369761.

This change also makes the description for the --strip-unneeded switch
consistent between the two docs.

Reviewed by: MaskRay

Differential Revision: https://reviews.llvm.org/D67546

llvm-svn: 371855
2019-09-13 13:26:52 +00:00
DeForest Richards 3b6d9c0bab [Docs] Adds page for reference docs
Adds a Reference Documentation page for LLVM and API reference documentation.

llvm-svn: 371782
2019-09-12 22:17:04 +00:00
James Henderson f145456fc4 [docs][llvm-strip] Remove unnecessary whitespace for consistency
llvm-svn: 371739
2019-09-12 14:24:04 +00:00
Craig Topper 635d383fad [X86] Enable -mprefer-vector-width=256 by default for Skylake-avx512 and later Intel CPUs.
AVX512 instructions can cause a frequency drop on these CPUs. This
can negate the performance gains from using wider vectors. Enabling
prefer-vector-width=256 will prevent generation of zmm registers
unless explicit 512 bit operations are used in the original source
code.

I believe gcc and icc both do something similar to this by default.

Differential Revision: https://reviews.llvm.org/D67259

llvm-svn: 371694
2019-09-11 23:54:36 +00:00
Adrian Prantl 09f320ad34 Update link to the DWARF spec.
llvm-svn: 371650
2019-09-11 19:57:29 +00:00
Adrian Prantl 4a5dd4a881 Update documentation.
llvm-svn: 371648
2019-09-11 19:49:38 +00:00
Sanjay Patel 3183466aa6 [LangRef] add link for fma intrinsic
llvm-svn: 371615
2019-09-11 13:25:32 +00:00
Sanjay Patel b3b2064c51 [LangRef] fix punctuation; NFC
llvm-svn: 371612
2019-09-11 12:22:24 +00:00
Alina Sbirlea a6e0bef312 Update ReleaseNotes: add enabling of MemorySSA.
llvm-svn: 371569
2019-09-10 23:22:37 +00:00
Djordje Todorovic b21cc626c9 Revert "[utils] Implement the llvm-locstats tool"
This reverts commit rL371520.

llvm-svn: 371527
2019-09-10 14:48:52 +00:00
Djordje Todorovic 54008972d1 [utils] Implement the llvm-locstats tool
The tool reports verbose output for the DWARF debug location coverage.
The llvm-locstats for each variable or formal parameter DIE computes what
percentage from the code section bytes, where it is in scope, it has
location description. The line 0 shows the number (and the percentage) of
DIEs with no location information, but the line 100 shows the number (and
the percentage) of DIEs where there is location information in all code
section bytes (where the variable or parameter is in the scope). The line
50..59 shows the number (and the percentage) of DIEs where the location
information is in between 50 and 59 percentage of its scope covered.

The tool will be very useful for tracking improvements regarding the
"debugging optimized code" support with LLVM ecosystem.

Differential Revision: https://reviews.llvm.org/D66526

llvm-svn: 371520
2019-09-10 13:47:03 +00:00
Evgeniy Stepanov f0e2755b45 LangRef: mention MSan's problem with speculative conditional branches.
Summary:
This short blurb aims to disallow optimizations like we had to revert
(under MSan) in
  https://reviews.llvm.org/D21165
  https://bugs.llvm.org/show_bug.cgi?id=28054
  https://reviews.llvm.org/D67205

Reviewers: vitalybuka, efriedma

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67244

llvm-svn: 371461
2019-09-09 22:24:57 +00:00
Craig Topper 5ebd0a6e88 [SelectionDAG] Remove ISD::FP_ROUND_INREG
I don't think anything in tree creates this node. So all of this
code appears to be dead.

Code coverage agrees
http://lab.llvm.org:8080/coverage/coverage-reports/llvm/coverage/Users/buildslave/jenkins/workspace/clang-stage2-coverage-R/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp.html

Differential Revision: https://reviews.llvm.org/D67312

llvm-svn: 371431
2019-09-09 17:54:44 +00:00
Bjorn Pettersson 5e331e4ce8 [Intrinsic] Add the llvm.umul.fix.sat intrinsic
Summary:
Add an intrinsic that takes 2 unsigned integers with
the scale of them provided as the third argument and
performs fixed point multiplication on them. The
result is saturated and clamped between the largest and
smallest representable values of the first 2 operands.

This is a part of implementing fixed point arithmetic
in clang where some of the more complex operations
will be implemented as intrinsics.

Patch by: leonardchan, bjope

Reviewers: RKSimon, craig.topper, bevinh, leonardchan, lebedev.ri, spatel

Reviewed By: leonardchan

Subscribers: ychen, wuzish, nemanjai, MaskRay, jsji, jdoerfert, Ka-Ka, hiraditya, rjmccall, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D57836

llvm-svn: 371308
2019-09-07 12:16:14 +00:00
DeForest Richards 4533b4a3a6 Docs: Update Community section on homepage
This commit includes the following changes: Adds a Getting Involved section under Community. Moves the Development Process section under Community. Moves Sphinx Quickstart Template and How to submit an LLVM bug report from User Guides section to Getting Involved.

llvm-svn: 371127
2019-09-05 21:24:47 +00:00
Sylvestre Ledru 4e281f70ca doc update: explain that Z3 is only for clang SA - thanks to LebedevRI for the suggestion
llvm-svn: 371110
2019-09-05 19:50:56 +00:00
Sylvestre Ledru 37fcd3a33e document the LLVM_ENABLE_Z3_SOLVER option
llvm-svn: 371109
2019-09-05 19:38:15 +00:00
DeForest Richards e3e6624ca2 Docs: Move Documentation sections to separate pages.
Updates the links on the homepage by moving the User Guides, Programming Documentation, and Subsystem Documentation sections to separate pages. Also changes "Overview" to "About" at the top of the LLVM Docs homepage. This work is part of the Google Season of Docs project.

llvm-svn: 371096
2019-09-05 17:30:52 +00:00
Guillaume Chatelet aff45e4b23 [LLVM][Alignment] Make functions using log of alignment explicit
Summary:
This patch renames functions that takes or returns alignment as log2, this patch will help with the transition to llvm::Align.
The renaming makes it explicit that we deal with log(alignment) instead of a power of two alignment.
A few renames uncovered dubious assignments:

 - `MirParser`/`MirPrinter` was expecting powers of two but `MachineFunction` and `MachineBasicBlock` were using deal with log2(align). This patch fixes it and updates the documentation.
 - `MachineBlockPlacement` exposes two flags (`align-all-blocks` and `align-all-nofallthru-blocks`) supposedly interpreted as power of two alignments, internally these values are interpreted as log2(align). This patch updates the documentation,
 - `MachineFunctionexposes` exposes `align-all-functions` also interpreted as power of two alignment, internally this value is interpreted as log2(align). This patch updates the documentation,

Reviewers: lattner, thegameg, courbet

Subscribers: dschuff, arsenm, jyknight, dylanmckay, sdardis, nemanjai, jvesely, nhaehnle, javed.absar, hiraditya, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, dexonsmith, PkmX, jocewei, jsji, Jim, s.egerton, llvm-commits, courbet

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65945

llvm-svn: 371045
2019-09-05 10:00:22 +00:00
Lang Hames e4526330b3 [docs] Add some comments to the inline LLJIT example.
llvm-svn: 370950
2019-09-04 18:38:26 +00:00
Vedant Kumar 0fcfe89717 [llvm-profdata] Add mode to recover from profile read failures
Add a mode in which profile read errors are not immediately treated as
fatal. In this mode, merging makes forward progress and reports failure
only if no inputs can be read.

Differential Revision: https://reviews.llvm.org/D66985

llvm-svn: 370827
2019-09-03 22:23:16 +00:00
Roman Lebedev bdd65351d3 Revert r370454 "[LoopIdiomRecognize] BCmp loop idiom recognition"
https://bugs.llvm.org/show_bug.cgi?id=43206 was filed,
claiming that there is a miscompilation.
Reverting until i investigate.

This reverts commit r370454

llvm-svn: 370788
2019-09-03 17:14:56 +00:00
Kerry McLaughlin da4ef9b4c8 [SVE][Inline-Asm] Support for SVE asm operands
Summary:
Adds the following inline asm constraints for SVE:
  - w: SVE vector register with full range, Z0 to Z31
  - x: Restricted to registers Z0 to Z15 inclusive.
  - y: Restricted to registers Z0 to Z7 inclusive.

This change also adds the "z" modifier to interpret a register as an SVE register.

Not all of the bitconvert patterns added by this patch are used, but they have been included here for completeness.

Reviewers: t.p.northover, sdesmalen, rovka, momchil.velikov, rengolin, cameron.mcinally, greened

Reviewed By: sdesmalen

Subscribers: javed.absar, tschuett, rkruppe, psnobl, cfe-commits, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66302

llvm-svn: 370673
2019-09-02 16:12:31 +00:00
Thomas Preud'homme a291b950db [FileCheck] Forbid using var defined on same line
Summary:
Commit r366897 introduced the possibility to set a variable from an
expression, such as [[#VAR2:VAR1+3]]. While introducing this feature, it
introduced extra logic to allow using such a variable on the same line
later on. Unfortunately that extra logic is flawed as it relies on a
mapping from variable to expression defining it when the mapping is from
variable definition to expression. This flaw causes among other issues
PR42896.

This commit avoids the problem by forbidding all use of a variable
defined on the same line, and removes the now useless logic. Redesign
will be done in a later commit because it will require some amount of
refactoring first for the solution to be clean. One example is the need
for some sort of transaction mechanism to set a variable temporarily and
from an expression and rollback if the CHECK pattern does not match so
that diagnostics show the right variable values.

Reviewers: jhenderson, chandlerc, jdenny, probinson, grimar, arichardson, rnk

Subscribers: JonChesterfield, rogfer01, hfinkel, kristina, rnk, tra, arichardson, grimar, dblaikie, probinson, llvm-commits, hiraditya

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66141

llvm-svn: 370663
2019-09-02 14:04:00 +00:00
Bjorn Pettersson e1ac21c4a2 [LangRef] Update saturating examples for llvm.smul.fix.sat. NFC
Some saturation examples for llvm.smul.fix.sat were not showing
the correct result. I've adjusted the operands to make sure that
we actually trigger overflow in those examples.

llvm-svn: 370566
2019-08-31 09:01:16 +00:00
Craig Topper 18e8d02e8c [X86] Pass v32i16/v64i8 in zmm registers on KNL target.
gcc and icc pass these types in zmm registers in zmm registers.

This patch implements a quick hack to override the register
type before calling convention handling to one that is legal.
Longer term we might want to do something similar to 256-bit
integer registers on AVX1 where we just split all the operations.

Fixes PR42957

Differential Revision: https://reviews.llvm.org/D66708

llvm-svn: 370495
2019-08-30 17:35:08 +00:00
Chris Jackson fa1fe93789 [llvm-objcopy] Allow the visibility of symbols created by --binary and
--add-symbol to be specified with --new-symbol-visibility

llvm-svn: 370458
2019-08-30 10:17:16 +00:00
Roman Lebedev 5c9f3cfec7 [LoopIdiomRecognize] BCmp loop idiom recognition
Summary:
@mclow.lists brought up this issue up in IRC.
It is a reasonably common problem to compare some two values for equality.
Those may be just some integers, strings or arrays of integers.

In C, there is `memcmp()`, `bcmp()` functions.
In C++, there exists `std::equal()` algorithm.
One can also write that function manually.

libstdc++'s `std::equal()` is specialized to directly call `memcmp()` for
various types, but not `std::byte` from C++2a. https://godbolt.org/z/mx2ejJ

libc++ does not do anything like that, it simply relies on simple C++'s
`operator==()`. https://godbolt.org/z/er0Zwf (GOOD!)

So likely, there exists a certain performance opportunities.
Let's compare performance of naive `std::equal()` (no `memcmp()`) with one that
is using `memcmp()` (in this case, compiled with modified compiler). {F8768213}

```
#include <algorithm>
#include <cmath>
#include <cstdint>
#include <iterator>
#include <limits>
#include <random>
#include <type_traits>
#include <utility>
#include <vector>

#include "benchmark/benchmark.h"

template <class T>
bool equal(T* a, T* a_end, T* b) noexcept {
  for (; a != a_end; ++a, ++b) {
    if (*a != *b) return false;
  }
  return true;
}

template <typename T>
std::vector<T> getVectorOfRandomNumbers(size_t count) {
  std::random_device rd;
  std::mt19937 gen(rd());
  std::uniform_int_distribution<T> dis(std::numeric_limits<T>::min(),
                                       std::numeric_limits<T>::max());
  std::vector<T> v;
  v.reserve(count);
  std::generate_n(std::back_inserter(v), count,
                  [&dis, &gen]() { return dis(gen); });
  assert(v.size() == count);
  return v;
}

struct Identical {
  template <typename T>
  static std::pair<std::vector<T>, std::vector<T>> Gen(size_t count) {
    auto Tmp = getVectorOfRandomNumbers<T>(count);
    return std::make_pair(Tmp, std::move(Tmp));
  }
};

struct InequalHalfway {
  template <typename T>
  static std::pair<std::vector<T>, std::vector<T>> Gen(size_t count) {
    auto V0 = getVectorOfRandomNumbers<T>(count);
    auto V1 = V0;
    V1[V1.size() / size_t(2)]++;  // just change the value.
    return std::make_pair(std::move(V0), std::move(V1));
  }
};

template <class T, class Gen>
void BM_bcmp(benchmark::State& state) {
  const size_t Length = state.range(0);

  const std::pair<std::vector<T>, std::vector<T>> Data =
      Gen::template Gen<T>(Length);
  const std::vector<T>& a = Data.first;
  const std::vector<T>& b = Data.second;
  assert(a.size() == Length && b.size() == a.size());

  benchmark::ClobberMemory();
  benchmark::DoNotOptimize(a);
  benchmark::DoNotOptimize(a.data());
  benchmark::DoNotOptimize(b);
  benchmark::DoNotOptimize(b.data());

  for (auto _ : state) {
    const bool is_equal = equal(a.data(), a.data() + a.size(), b.data());
    benchmark::DoNotOptimize(is_equal);
  }
  state.SetComplexityN(Length);
  state.counters["eltcnt"] =
      benchmark::Counter(Length, benchmark::Counter::kIsIterationInvariant);
  state.counters["eltcnt/sec"] =
      benchmark::Counter(Length, benchmark::Counter::kIsIterationInvariantRate);
  const size_t BytesRead = 2 * sizeof(T) * Length;
  state.counters["bytes_read/iteration"] =
      benchmark::Counter(BytesRead, benchmark::Counter::kDefaults,
                         benchmark::Counter::OneK::kIs1024);
  state.counters["bytes_read/sec"] = benchmark::Counter(
      BytesRead, benchmark::Counter::kIsIterationInvariantRate,
      benchmark::Counter::OneK::kIs1024);
}

template <typename T>
static void CustomArguments(benchmark::internal::Benchmark* b) {
  const size_t L2SizeBytes = []() {
    for (const benchmark::CPUInfo::CacheInfo& I :
         benchmark::CPUInfo::Get().caches) {
      if (I.level == 2) return I.size;
    }
    return 0;
  }();
  // What is the largest range we can check to always fit within given L2 cache?
  const size_t MaxLen = L2SizeBytes / /*total bufs*/ 2 /
                        /*maximal elt size*/ sizeof(T) / /*safety margin*/ 2;
  b->RangeMultiplier(2)->Range(1, MaxLen)->Complexity(benchmark::oN);
}

BENCHMARK_TEMPLATE(BM_bcmp, uint8_t, Identical)
    ->Apply(CustomArguments<uint8_t>);
BENCHMARK_TEMPLATE(BM_bcmp, uint16_t, Identical)
    ->Apply(CustomArguments<uint16_t>);
BENCHMARK_TEMPLATE(BM_bcmp, uint32_t, Identical)
    ->Apply(CustomArguments<uint32_t>);
BENCHMARK_TEMPLATE(BM_bcmp, uint64_t, Identical)
    ->Apply(CustomArguments<uint64_t>);

BENCHMARK_TEMPLATE(BM_bcmp, uint8_t, InequalHalfway)
    ->Apply(CustomArguments<uint8_t>);
BENCHMARK_TEMPLATE(BM_bcmp, uint16_t, InequalHalfway)
    ->Apply(CustomArguments<uint16_t>);
BENCHMARK_TEMPLATE(BM_bcmp, uint32_t, InequalHalfway)
    ->Apply(CustomArguments<uint32_t>);
BENCHMARK_TEMPLATE(BM_bcmp, uint64_t, InequalHalfway)
    ->Apply(CustomArguments<uint64_t>);
```
{F8768210}
```
$ ~/src/googlebenchmark/tools/compare.py --no-utest benchmarks build-{old,new}/test/llvm-bcmp-bench
RUNNING: build-old/test/llvm-bcmp-bench --benchmark_out=/tmp/tmpb6PEUx
2019-04-25 21:17:11
Running build-old/test/llvm-bcmp-bench
Run on (8 X 4000 MHz CPU s)
CPU Caches:
  L1 Data 16K (x8)
  L1 Instruction 64K (x4)
  L2 Unified 2048K (x4)
  L3 Unified 8192K (x1)
Load Average: 0.65, 3.90, 4.14
---------------------------------------------------------------------------------------------------
Benchmark                                         Time             CPU   Iterations UserCounters...
---------------------------------------------------------------------------------------------------
<...>
BM_bcmp<uint8_t, Identical>/512000           432131 ns       432101 ns         1613 bytes_read/iteration=1000k bytes_read/sec=2.20706G/s eltcnt=825.856M eltcnt/sec=1.18491G/s
BM_bcmp<uint8_t, Identical>_BigO               0.86 N          0.86 N
BM_bcmp<uint8_t, Identical>_RMS                   8 %             8 %
<...>
BM_bcmp<uint16_t, Identical>/256000          161408 ns       161409 ns         4027 bytes_read/iteration=1000k bytes_read/sec=5.90843G/s eltcnt=1030.91M eltcnt/sec=1.58603G/s
BM_bcmp<uint16_t, Identical>_BigO              0.67 N          0.67 N
BM_bcmp<uint16_t, Identical>_RMS                 25 %            25 %
<...>
BM_bcmp<uint32_t, Identical>/128000           81497 ns        81488 ns         8415 bytes_read/iteration=1000k bytes_read/sec=11.7032G/s eltcnt=1077.12M eltcnt/sec=1.57078G/s
BM_bcmp<uint32_t, Identical>_BigO              0.71 N          0.71 N
BM_bcmp<uint32_t, Identical>_RMS                 42 %            42 %
<...>
BM_bcmp<uint64_t, Identical>/64000            50138 ns        50138 ns        10909 bytes_read/iteration=1000k bytes_read/sec=19.0209G/s eltcnt=698.176M eltcnt/sec=1.27647G/s
BM_bcmp<uint64_t, Identical>_BigO              0.84 N          0.84 N
BM_bcmp<uint64_t, Identical>_RMS                 27 %            27 %
<...>
BM_bcmp<uint8_t, InequalHalfway>/512000      192405 ns       192392 ns         3638 bytes_read/iteration=1000k bytes_read/sec=4.95694G/s eltcnt=1.86266G eltcnt/sec=2.66124G/s
BM_bcmp<uint8_t, InequalHalfway>_BigO          0.38 N          0.38 N
BM_bcmp<uint8_t, InequalHalfway>_RMS              3 %             3 %
<...>
BM_bcmp<uint16_t, InequalHalfway>/256000     127858 ns       127860 ns         5477 bytes_read/iteration=1000k bytes_read/sec=7.45873G/s eltcnt=1.40211G eltcnt/sec=2.00219G/s
BM_bcmp<uint16_t, InequalHalfway>_BigO         0.50 N          0.50 N
BM_bcmp<uint16_t, InequalHalfway>_RMS             0 %             0 %
<...>
BM_bcmp<uint32_t, InequalHalfway>/128000      49140 ns        49140 ns        14281 bytes_read/iteration=1000k bytes_read/sec=19.4072G/s eltcnt=1.82797G eltcnt/sec=2.60478G/s
BM_bcmp<uint32_t, InequalHalfway>_BigO         0.40 N          0.40 N
BM_bcmp<uint32_t, InequalHalfway>_RMS            18 %            18 %
<...>
BM_bcmp<uint64_t, InequalHalfway>/64000       32101 ns        32099 ns        21786 bytes_read/iteration=1000k bytes_read/sec=29.7101G/s eltcnt=1.3943G eltcnt/sec=1.99381G/s
BM_bcmp<uint64_t, InequalHalfway>_BigO         0.50 N          0.50 N
BM_bcmp<uint64_t, InequalHalfway>_RMS             1 %             1 %
RUNNING: build-new/test/llvm-bcmp-bench --benchmark_out=/tmp/tmpQ46PP0
2019-04-25 21:19:29
Running build-new/test/llvm-bcmp-bench
Run on (8 X 4000 MHz CPU s)
CPU Caches:
  L1 Data 16K (x8)
  L1 Instruction 64K (x4)
  L2 Unified 2048K (x4)
  L3 Unified 8192K (x1)
Load Average: 1.01, 2.85, 3.71
---------------------------------------------------------------------------------------------------
Benchmark                                         Time             CPU   Iterations UserCounters...
---------------------------------------------------------------------------------------------------
<...>
BM_bcmp<uint8_t, Identical>/512000            18593 ns        18590 ns        37565 bytes_read/iteration=1000k bytes_read/sec=51.2991G/s eltcnt=19.2333G eltcnt/sec=27.541G/s
BM_bcmp<uint8_t, Identical>_BigO               0.04 N          0.04 N
BM_bcmp<uint8_t, Identical>_RMS                  37 %            37 %
<...>
BM_bcmp<uint16_t, Identical>/256000           18950 ns        18948 ns        37223 bytes_read/iteration=1000k bytes_read/sec=50.3324G/s eltcnt=9.52909G eltcnt/sec=13.511G/s
BM_bcmp<uint16_t, Identical>_BigO              0.08 N          0.08 N
BM_bcmp<uint16_t, Identical>_RMS                 34 %            34 %
<...>
BM_bcmp<uint32_t, Identical>/128000           18627 ns        18627 ns        37895 bytes_read/iteration=1000k bytes_read/sec=51.198G/s eltcnt=4.85056G eltcnt/sec=6.87168G/s
BM_bcmp<uint32_t, Identical>_BigO              0.16 N          0.16 N
BM_bcmp<uint32_t, Identical>_RMS                 35 %            35 %
<...>
BM_bcmp<uint64_t, Identical>/64000            18855 ns        18855 ns        37458 bytes_read/iteration=1000k bytes_read/sec=50.5791G/s eltcnt=2.39731G eltcnt/sec=3.3943G/s
BM_bcmp<uint64_t, Identical>_BigO              0.32 N          0.32 N
BM_bcmp<uint64_t, Identical>_RMS                 33 %            33 %
<...>
BM_bcmp<uint8_t, InequalHalfway>/512000        9570 ns         9569 ns        73500 bytes_read/iteration=1000k bytes_read/sec=99.6601G/s eltcnt=37.632G eltcnt/sec=53.5046G/s
BM_bcmp<uint8_t, InequalHalfway>_BigO          0.02 N          0.02 N
BM_bcmp<uint8_t, InequalHalfway>_RMS             29 %            29 %
<...>
BM_bcmp<uint16_t, InequalHalfway>/256000       9547 ns         9547 ns        74343 bytes_read/iteration=1000k bytes_read/sec=99.8971G/s eltcnt=19.0318G eltcnt/sec=26.8159G/s
BM_bcmp<uint16_t, InequalHalfway>_BigO         0.04 N          0.04 N
BM_bcmp<uint16_t, InequalHalfway>_RMS            29 %            29 %
<...>
BM_bcmp<uint32_t, InequalHalfway>/128000       9396 ns         9394 ns        73521 bytes_read/iteration=1000k bytes_read/sec=101.518G/s eltcnt=9.41069G eltcnt/sec=13.6255G/s
BM_bcmp<uint32_t, InequalHalfway>_BigO         0.08 N          0.08 N
BM_bcmp<uint32_t, InequalHalfway>_RMS            30 %            30 %
<...>
BM_bcmp<uint64_t, InequalHalfway>/64000        9499 ns         9498 ns        73802 bytes_read/iteration=1000k bytes_read/sec=100.405G/s eltcnt=4.72333G eltcnt/sec=6.73808G/s
BM_bcmp<uint64_t, InequalHalfway>_BigO         0.16 N          0.16 N
BM_bcmp<uint64_t, InequalHalfway>_RMS            28 %            28 %
Comparing build-old/test/llvm-bcmp-bench to build-new/test/llvm-bcmp-bench
Benchmark                                                  Time             CPU      Time Old      Time New       CPU Old       CPU New
---------------------------------------------------------------------------------------------------------------------------------------
<...>
BM_bcmp<uint8_t, Identical>/512000                      -0.9570         -0.9570        432131         18593        432101         18590
<...>
BM_bcmp<uint16_t, Identical>/256000                     -0.8826         -0.8826        161408         18950        161409         18948
<...>
BM_bcmp<uint32_t, Identical>/128000                     -0.7714         -0.7714         81497         18627         81488         18627
<...>
BM_bcmp<uint64_t, Identical>/64000                      -0.6239         -0.6239         50138         18855         50138         18855
<...>
BM_bcmp<uint8_t, InequalHalfway>/512000                 -0.9503         -0.9503        192405          9570        192392          9569
<...>
BM_bcmp<uint16_t, InequalHalfway>/256000                -0.9253         -0.9253        127858          9547        127860          9547
<...>
BM_bcmp<uint32_t, InequalHalfway>/128000                -0.8088         -0.8088         49140          9396         49140          9394
<...>
BM_bcmp<uint64_t, InequalHalfway>/64000                 -0.7041         -0.7041         32101          9499         32099          9498
```

What can we tell from the benchmark?
* Performance of naive equality check somewhat improves with element size,
  maxing out at eltcnt/sec=1.58603G/s for uint16_t, or bytes_read/sec=19.0209G/s
  for uint64_t. I think, that instability implies performance problems.
* Performance of `memcmp()`-aware benchmark always maxes out at around
  bytes_read/sec=51.2991G/s for every type. That is 2.6x the throughput of the
  naive variant!
* eltcnt/sec metric for the `memcmp()`-aware benchmark maxes out at
  eltcnt/sec=27.541G/s for uint8_t (was: eltcnt/sec=1.18491G/s, so 24x) and
  linearly decreases with element size.
  For uint64_t, it's ~4x+ the elements/second.
* The call obvious is more pricey than the loop, with small element count.
  As it can be seen from the full output {F8768210}, the `memcmp()` is almost
  universally worse, independent of the element size (and thus buffer size) when
  element count is less than 8.

So all in all, bcmp idiom does indeed pose untapped performance headroom.
This diff does implement said idiom recognition. I think a reasonable test
coverage is present, but do tell if there is anything obvious missing.

Now, quality. This does succeed to build and pass the test-suite, at least
without any non-bundled elements. {F8768216} {F8768217}
This transform fires 91 times:
```
$ /build/test-suite/utils/compare.py -m loop-idiom.NumBCmp result-new.json
Tests: 1149
Metric: loop-idiom.NumBCmp

Program                                         result-new

MultiSourc...Benchmarks/7zip/7zip-benchmark    79.00
MultiSource/Applications/d/make_dparser         3.00
SingleSource/UnitTests/vla                      2.00
MultiSource/Applications/Burg/burg              1.00
MultiSourc.../Applications/JM/lencod/lencod     1.00
MultiSource/Applications/lemon/lemon            1.00
MultiSource/Benchmarks/Bullet/bullet            1.00
MultiSourc...e/Benchmarks/MallocBench/gs/gs     1.00
MultiSourc...gs-C/TimberWolfMC/timberwolfmc     1.00
MultiSourc...Prolangs-C/simulator/simulator     1.00
```
The size changes are:
I'm not sure what's going on with SingleSource/UnitTests/vla.test yet, did not look.
```
$ /build/test-suite/utils/compare.py -m size..text result-{old,new}.json --filter-hash
Tests: 1149
Same hash: 907 (filtered out)
Remaining: 242
Metric: size..text

Program                                        result-old result-new diff
test-suite...ingleSource/UnitTests/vla.test   753.00     833.00     10.6%
test-suite...marks/7zip/7zip-benchmark.test   1001697.00 966657.00  -3.5%
test-suite...ngs-C/simulator/simulator.test   32369.00   32321.00   -0.1%
test-suite...plications/d/make_dparser.test   89585.00   89505.00   -0.1%
test-suite...ce/Applications/Burg/burg.test   40817.00   40785.00   -0.1%
test-suite.../Applications/lemon/lemon.test   47281.00   47249.00   -0.1%
test-suite...TimberWolfMC/timberwolfmc.test   250065.00  250113.00   0.0%
test-suite...chmarks/MallocBench/gs/gs.test   149889.00  149873.00  -0.0%
test-suite...ications/JM/lencod/lencod.test   769585.00  769569.00  -0.0%
test-suite.../Benchmarks/Bullet/bullet.test   770049.00  770049.00   0.0%
test-suite...HMARK_ANISTROPIC_DIFFUSION/128    NaN        NaN        nan%
test-suite...HMARK_ANISTROPIC_DIFFUSION/256    NaN        NaN        nan%
test-suite...CHMARK_ANISTROPIC_DIFFUSION/64    NaN        NaN        nan%
test-suite...CHMARK_ANISTROPIC_DIFFUSION/32    NaN        NaN        nan%
test-suite...ENCHMARK_BILATERAL_FILTER/64/4    NaN        NaN        nan%
Geomean difference                                                   nan%
         result-old    result-new       diff
count  1.000000e+01  10.00000      10.000000
mean   3.152090e+05  311695.40000  0.006749
std    3.790398e+05  372091.42232  0.036605
min    7.530000e+02  833.00000    -0.034981
25%    4.243300e+04  42401.00000  -0.000866
50%    1.197370e+05  119689.00000 -0.000392
75%    6.397050e+05  639705.00000 -0.000005
max    1.001697e+06  966657.00000  0.106242
```

I don't have timings though.

And now to the code. The basic idea is to completely replace the whole loop.
If we can't fully kill it, don't transform.
I have left one or two comments in the code, so hopefully it can be understood.

Also, there is a few TODO's that i have left for follow-ups:
* widening of `memcmp()`/`bcmp()`
* step smaller than the comparison size
* Metadata propagation
* more than two blocks as long as there is still a single backedge?
* ???

Reviewers: reames, fhahn, mkazantsev, chandlerc, craig.topper, courbet

Reviewed By: courbet

Subscribers: hiraditya, xbolva00, nikic, jfb, gchatelet, courbet, llvm-commits, mclow.lists

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D61144

llvm-svn: 370454
2019-08-30 09:51:23 +00:00
Craig Topper 5a43fdd313 [X86] Remove what little support we had for MPX
-Deprecate -mmpx and -mno-mpx command line options
-Remove CPUID detection of mpx for -march=native
-Remove MPX from all CPUs
-Remove MPX preprocessor define

I've left the "mpx" string in the backend so we don't fail on old IR, but its not connected to anything.

gcc has also deprecated these command line options. https://www.phoronix.com/scan.php?page=news_item&px=GCC-Patch-To-Drop-MPX

Differential Revision: https://reviews.llvm.org/D66669

llvm-svn: 370393
2019-08-29 18:09:02 +00:00
Craig Topper a47db7110d [X86][ReleaseNotes] Add a note about the switch to widening legalization for narrow vectors.
llvm-svn: 370233
2019-08-28 17:18:56 +00:00
Kevin P. Neal ddf13c00ed [FPEnv] Add fptosi and fptoui constrained intrinsics.
This implements constrained floating point intrinsics for FP to signed and
unsigned integers.

Quoting from D32319:
The purpose of the constrained intrinsics is to force the optimizer to
respect the restrictions that will be necessary to support things like the
STDC FENV_ACCESS ON pragma without interfering with optimizations when
these restrictions are not needed.

Reviewed by:	Andrew Kaylor, Craig Topper, Hal Finkel, Cameron McInally, Roman Lebedev, Kit Barton
Approved by:	Craig Topper
Differential Revision:	http://reviews.llvm.org/D63782

llvm-svn: 370228
2019-08-28 16:33:36 +00:00
Shafik Yaghmour 5dca5efc0b Debug Info: Support for DW_AT_export_symbols for anonymous structs
This implements the DWARF 5 feature described in:

http://dwarfstd.org/ShowIssue.php?issue=141212.1

To support recognizing anonymous structs:

  struct A {
    struct { // Anonymous struct
        int y;
    };
  }   a;

This patch adds a new (DI)flag to LLVM metadata:

ExportSymbols

Differential Revision: https://reviews.llvm.org/D66352

llvm-svn: 369781
2019-08-23 17:19:21 +00:00
Sylvestre Ledru c2ca965c89 Fix some regressions caused by r369553 on old versions of Debian and Ubuntu
It was causing some errors like:

Encoding error:
'ascii' codec can't decode byte 0xe2 in position 341: ordinal not in range(128)
The full traceback has been saved in /tmp/sphinx-err-y2fq4dtb.log, if you want to report the issue to the developers.

llvm-svn: 369644
2019-08-22 12:16:08 +00:00
Mitch Phillips 84b762af3b [docs] Add GwpAsan to toctree.
Reverts rL369556 in the process, as it's no longer needed.

llvm-svn: 369560
2019-08-21 18:31:03 +00:00
Jordan Rupprecht e4876c9d71 [docs] Fix GwpAsan.rst
llvm-svn: 369556
2019-08-21 18:09:31 +00:00
Mitch Phillips 2213bbb57a Add newline to GWP-ASan sphinx document.
Should fix the document builder.

llvm-svn: 369554
2019-08-21 18:03:11 +00:00
Jordan Rupprecht a28b8d78e4 [docs] Convert remaining command guide entries from md to rst.
Summary:
Linking between markdown and rst files is currently not supported very well, e.g. the current llvm-addr2line docs [1] link to "llvm-symbolizer" instead of "llvm-symbolizer.html". This is weirdly broken in different ways depending on which versions of sphinx and recommonmark are being used, so workaround the bug by using rst everywhere.

[1] http://llvm.org/docs/CommandGuide/llvm-addr2line.html

Reviewers: jhenderson

Reviewed By: jhenderson

Subscribers: lebedev.ri, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66305

llvm-svn: 369553
2019-08-21 18:00:17 +00:00
Mitch Phillips c776f3f3c2 [GWP-ASan] Add public-facing documentation [6].
Summary:
Note: Do not submit this documentation until Scudo support is reviewed and submitted (should be #[5]).

See D60593 for further information.

This patch introduces the public-facing documentation for GWP-ASan, as well as updating the definition of one of the options, which wasn't properly merged. The document describes the design and features of GWP-ASan, as well as how to use GWP-ASan from both a user's standpoint, and development documentation for supporting allocators.

Reviewers: jfb, morehouse, vlad.tsyrklevich

Reviewed By: morehouse, vlad.tsyrklevich

Subscribers: kcc, dexonsmith, kubamracek, cryptoad, jfb, #sanitizers, llvm-commits, vlad.tsyrklevich, morehouse

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D62875

llvm-svn: 369552
2019-08-21 17:53:51 +00:00
DeForest Richards c944438dfd [Docs] Test commit
Fixes typo - Removes extra space between last word of sentence and period.

llvm-svn: 369216
2019-08-18 19:07:10 +00:00
Siva Chandra 0890f0f3de Add LLVMLibC proposal to docs/index.rst.
Reviewers: rupprecht

Subscribers: arphaman, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66307

llvm-svn: 369030
2019-08-15 18:08:11 +00:00
Jonas Devlieghere 0eaee545ee [llvm] Migrate llvm::make_unique to std::make_unique
Now that we've moved to C++14, we no longer need the llvm::make_unique
implementation from STLExtras.h. This patch is a mechanical replacement
of (hopefully) all the llvm::make_unique instances across the monorepo.

llvm-svn: 369013
2019-08-15 15:54:37 +00:00
Siva Chandra 1c34d10776 Add a proposal for a libc project under the LLVM umbrella.
Reviewers: chandlerc, dlj, echristo, hfinkel, jfb, zturner

Subscribers: dexonsmith, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D64939

llvm-svn: 369012
2019-08-15 15:50:42 +00:00
Florian Hahn de1d6c8220 Add ptrmask intrinsic
This patch adds a ptrmask intrinsic which allows masking out bits of a
pointer that must be zero when accessing it, because of ABI alignment
requirements or a restriction of the meaningful bits of a pointer
through the data layout.

This avoids doing a ptrtoint/inttoptr round trip in some cases (e.g. tagged
pointers) and allows us to not lose information about the underlying
object.

Reviewers: nlopes, efriedma, hfinkel, sanjoy, jdoerfert, aqjune

Reviewed by: sanjoy, jdoerfert

Differential Revision: https://reviews.llvm.org/D59065

llvm-svn: 368986
2019-08-15 10:12:26 +00:00
Chris Jackson e5cdfbc65c [llvm-objcopy] Allow 'protected' visibility to be set when using
add-symbol

Reviewers: Maskray, rupprecht

Differential Revision: https://reviews.llvm.org/D65891

llvm-svn: 368982
2019-08-15 09:45:09 +00:00
Jordan Rupprecht 1737f71322 [docs] Fix sphinx doc generation errors
Summary:
Errors fixed:
 - GettingStarted: Duplicate explicit target name: "cmake"
 - GlobalISel: Unexpected indentation
 - LoopTerminology: Explicit markup ends without a blank line; unexpected unindent
 - ORCv2: Definition list ends without a blank line; unexpected unindent
 - Misc: document isn't included in any toctree

Verified that a clean docs build (`rm -rf docs/ && ninja docs-llvm-html`) passes with no errors. Spot checked the individual pages to make sure they look OK.

Reviewers: thakis, dsanders

Reviewed By: dsanders

Subscribers: arphaman, llvm-commits, lhames, rovka, dsanders, reames

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66183

llvm-svn: 368932
2019-08-14 22:18:01 +00:00
Erich Keane 0e85f18ded Add support in CMake to statically link the C++ standard library.
It is sometimes useful to have the C++ standard library linked into the
assembly when compiling clang, particularly when distributing a compiler
onto systems that don't have a copy of stdlibc++ or libc++ installed.

This functionality should work with either GCC or Clang as the host
compiler, though statically linking libc++ (as may be required for
licensing purposes) is only possible if the host compiler is Clang with
a copy of libc++ available.

Differential Revision: https://reviews.llvm.org/D65603

llvm-svn: 368907
2019-08-14 19:55:59 +00:00
JF Bastien b13c8ca9eb Move to C++14
Summary:
I just bumped the minimum compiler versions to support C++14 in D66188.

Following [our process](http://llvm.org/docs/DeveloperPolicy.html#toolchain) and [our previous agreement](http://lists.llvm.org/pipermail/llvm-dev/2019-January/129452.html), I'm now officially bumping the C++ version to 14 and updating the documentation.

Subscribers: mgorny, jkorous, dexonsmith, llvm-commits, chandlerc, thakis, EricWF, jyknight, lhames, JDevlieghere

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66195

llvm-svn: 368887
2019-08-14 17:39:07 +00:00
Craig Topper ffe91994a9 [LangRef] Remove opening [ that was missing a closing ] from call/callbr/invoke syntax.
It looks like this bracket was added when the addrspace was added.
before it. So I think it can jut be removed.

llvm-svn: 368861
2019-08-14 15:10:37 +00:00
JF Bastien 20644a9540 Remove minimum toolchain soft-error
Summary:
Back in January I changed the minimum toolchain version required to build clang
and LLVM: D57264. Since then we've release LLVM 8, following
[our process](http://llvm.org/docs/DeveloperPolicy.html#toolchain)
it's therefore now a good time to remove the soft-error and officially deprecate
older toolchains. I tried this out last Tursday night to see if any bots
complained, and I saw no complaints. I also manually audited bots and didn't see
any bot that should break, but their toolchain information is unreliable and
some bots are offline.

Once this patch stick we'll move to C++14 as we've
[already agreed](http://lists.llvm.org/pipermail/llvm-dev/2019-January/129452.html).

Subscribers: mgorny, jkorous, dexonsmith, llvm-commits, EricWF, thakis, chandlerc

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66188

llvm-svn: 368799
2019-08-14 04:30:51 +00:00
John McCall 94010b2b7f Extend coroutines to support a "returned continuation" lowering.
A quick contrast of this ABI with the currently-implemented ABI:

- Allocation is implicitly managed by the lowering passes, which is fine
  for frontends that are fine with assuming that allocation cannot fail.
  This assumption is necessary to implement dynamic allocas anyway.

- The lowering attempts to fit the coroutine frame into an opaque,
  statically-sized buffer before falling back on allocation; the same
  buffer must be provided to every resume point.  A buffer must be at
  least pointer-sized.

- The resume and destroy functions have been combined; the continuation
  function takes a parameter indicating whether it has succeeded.

- Conversely, every suspend point begins its own continuation function.

- The continuation function pointer is directly returned to the caller
  instead of being stored in the frame.  The continuation can therefore
  directly destroy the frame when exiting the coroutine instead of having
  to leave it in a defunct state.

- Other values can be returned directly to the caller instead of going
  through a promise allocation.  The frontend provides a "prototype"
  function declaration from which the type, calling convention, and
  attributes of the continuation functions are taken.

- On the caller side, the frontend can generate natural IR that directly
  uses the continuation functions as long as it prevents IPO with the
  coroutine until lowering has happened.  In combination with the point
  above, the frontend is almost totally in charge of the ABI of the
  coroutine.

- Unique-yield coroutines are given some special treatment.

llvm-svn: 368788
2019-08-14 03:53:17 +00:00
Diego Trevino Ferrer 72f996e4d9 [Bugpoint redesign] Fix nonlocal URI link in doc
Summary: Fixes documentation bot build  http://lab.llvm.org:8011/builders/llvm-sphinx-docs

Reviewers: JDevlieghere

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66022

llvm-svn: 368493
2019-08-09 21:48:47 +00:00
Michael Pozulp 3de981313c [Docs][llvm-strip] Fix an indentation issue.
llvm-svn: 368473
2019-08-09 19:41:13 +00:00
Michael Pozulp 4fe911d9dd [Docs][llvm-strip] Add help text to llvm-strip rst doc
Summary: Addresses https://bugs.llvm.org/show_bug.cgi?id=42383

Reviewers: jhenderson, alexshap, rupprecht

Reviewed By: jhenderson

Subscribers: wolfgangp, jakehehrlich, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65384

llvm-svn: 368464
2019-08-09 19:10:55 +00:00
Andrea Di Biagio cbec9af6bf [MCA] Add flag -show-encoding to llvm-mca.
Flag -show-encoding enables the printing of instruction encodings as part of the
the instruction info view.

Example (with flags -mtriple=x86_64--  -mcpu=btver2):

Instruction Info:
[1]: #uOps
[2]: Latency
[3]: RThroughput
[4]: MayLoad
[5]: MayStore
[6]: HasSideEffects (U)
[7]: Encoding Size

[1]    [2]    [3]    [4]    [5]    [6]    [7]    Encodings:     Instructions:
 1      2     1.00                         4     c5 f0 59 d0    vmulps   %xmm0, %xmm1, %xmm2
 1      4     1.00                         4     c5 eb 7c da    vhaddps  %xmm2, %xmm2, %xmm3
 1      4     1.00                         4     c5 e3 7c e3    vhaddps  %xmm3, %xmm3, %xmm4

In this example, column Encoding Size is the size in bytes of the instruction
encoding. Column Encodings reports the actual instruction encodings as byte
sequences in hex (objdump style).

The computation of encodings is done by a utility class named mca::CodeEmitter.

In future, I plan to expose the CodeEmitter to the instruction builder, so that
information about instruction encoding sizes can be used by the simulator. That
would be a first step towards simulating the throughput from the decoders in the
hardware frontend.

Differential Revision: https://reviews.llvm.org/D65948

llvm-svn: 368432
2019-08-09 11:26:27 +00:00
Diego Trevino Ferrer ddc64eb948 Added Delta IR Reduction Tool
Summary: Tool parses input IR file, and runs the delta debugging algorithm to reduce the functions inside the input file.

Reviewers: alexshap, chandlerc

Subscribers: mgorny, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D63672

> llvm-svn: 368071

llvm-svn: 368358
2019-08-08 22:16:33 +00:00
Daniel Sanders 5b40eb0572 [globalisel][legalizer] Attempt to write down the minimal legalization rules
Summary:
There aren't very many requirements on the legalization rules but we should
document them.

Reviewers: aditya_nandakumar, volkan, bogner, paquette, aemerson, rovka, arsenm, Petar.Avramovic

Subscribers: wdng, kristof.beyls, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D62423

# Conflicts:
#	llvm/docs/GlobalISel.rst

llvm-svn: 368321
2019-08-08 17:54:23 +00:00
Tim Corringham 4f64f1ba3c Add llvm.licm.disable metadata
For some targets the LICM pass can result in sub-optimal code in some
cases where it would be better not to run the pass, but it isn't
always possible to suppress the transformations heuristically.

Where the front-end has insight into such cases it is beneficial
to attach loop metadata to disable the pass - this change adds the
llvm.licm.disable metadata to enable that.

Differential Revision: https://reviews.llvm.org/D64557

llvm-svn: 368296
2019-08-08 13:46:17 +00:00
Anusha Basana a87f856f2d [llvm-lipo] Update llvm-lipo docs for -info -thin -create -replace -segalign flags
Summary:
The information for -info -thin -create -replace and -segalign flags are added to llvm-lipo.rst

Test Plan:

Reviewers: smeenai, alexshap, compnerd, mtrent

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65676

llvm-svn: 368235
2019-08-07 23:25:12 +00:00
Diego Trevino Ferrer d4d00ae6a2 Revert Added Delta IR Reduction Tool
This reverts r368071 (git commit a2584978f5bb41973d65a145b0d9459b81e3ac6d)

llvm-svn: 368217
2019-08-07 21:51:54 +00:00
Diego Trevino Ferrer b80c4c82d6 Added Delta IR Reduction Tool
Summary: Tool parses input IR file, and runs the delta debugging algorithm to reduce the functions inside the input file.

Reviewers: alexshap, chandlerc

Subscribers: mgorny, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D63672

> llvm-svn: 368071

llvm-svn: 368214
2019-08-07 21:37:11 +00:00
Sam Elliott 4f6737565b [RISCV][NFC] Document RISC-V-specific assembly constraints
llvm-svn: 368167
2019-08-07 13:08:07 +00:00
Petr Hosek 989679c371 Reverts commit r368117, r368115 and r368112
This reverts commits:

  "Added Delta IR Reduction Tool"
  "[Bugpoint redesign] Added Pass to Remove Global Variables"
  "Added Tool as Dependency to tests & fixed warnings"

Reduce/remove-funcs.ll is failing on bots.

llvm-svn: 368122
2019-08-07 05:15:34 +00:00
Diego Trevino Ferrer 099e5c5bba Added Delta IR Reduction Tool
Summary: Tool parses input IR file, and runs the delta debugging algorithm to reduce the functions inside the input file.

Reviewers: alexshap, chandlerc

Subscribers: mgorny, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D63672

> llvm-svn: 368071

llvm-svn: 368112
2019-08-07 00:00:52 +00:00
Dmitri Gribenko e2f17e2649 Revert "Added Delta IR Reduction Tool"
This reverts commit r368071, it broke buildbots.

llvm-svn: 368073
2019-08-06 19:40:37 +00:00
Diego Trevino Ferrer 800618f241 Added Delta IR Reduction Tool
Summary: Tool parses input IR file, and runs the delta debugging algorithm to reduce the functions inside the input file.

Reviewers: alexshap, chandlerc

Subscribers: mgorny, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D63672

llvm-svn: 368071
2019-08-06 18:59:11 +00:00
Hans Wennborg dba4dd1e8d Revert r367941 "Add a note to the release not about a potentially breaking optimization"
The note was moved to the release_90 branch in r367997.

llvm-svn: 367998
2019-08-06 08:32:33 +00:00
Johannes Doerfert e83f303938 [Attributor] Deduce the "no-return" attribute for functions
A function is "no-return" if we never reach a return instruction, either
because there are none or the ones that exist are dead.

Test have been adjusted:
  - either noreturn was added, or
  - noreturn was avoided by modifying the code.

The new noreturn_{sync,async} test make sure we do handle invoke
instructions with a noreturn (and potentially nowunwind) callee
correctly, even in the presence of potential asynchronous exceptions.

llvm-svn: 367948
2019-08-05 23:22:05 +00:00
Wolfgang Pieb c71c629926 [llvm-readelf] Support dumping of stack sizes sections with readelf --stack-sizes
Reviewers: jhenderson, grimar, rupprecht

Differential Revision: https://reviews.llvm.org/D65313

llvm-svn: 367942
2019-08-05 22:47:07 +00:00
Philip Reames e39e79358f Add a note to the release not about a potentially breaking optimization
This has come up twice already (once in pr42763 and once in the commit thread), so give warning of a new way in which UB can result in unexpected program behavior.

llvm-svn: 367941
2019-08-05 22:34:59 +00:00
Andrea Di Biagio 225655f82c [MCA][doc] Add a section for the 'Bottleneck Analysis'.
Also clarify the meaning of 'Block RThroughput' and 'RThroughput'.

llvm-svn: 367853
2019-08-05 13:18:37 +00:00
Fangrui Song d9b948b6eb Rename F_{None,Text,Append} to OF_{None,Text,Append}. NFC
F_{None,Text,Append} are kept for compatibility since r334221.

llvm-svn: 367800
2019-08-05 05:43:48 +00:00
Tim Northover a009a60a91 IR: print value numbers for unnamed function arguments
For consistency with normal instructions and clarity when reading IR,
it's best to print the %0, %1, ... names of function arguments in
definitions.

Also modifies the parser to accept IR in that form for obvious reasons.

llvm-svn: 367755
2019-08-03 14:28:34 +00:00
Yonghong Song d0ea05d5ef [BPF] annotate DIType metadata for builtin preseve_array_access_index()
Previously, debuginfo types are annotated to
IR builtin preserve_struct_access_index() and
preserve_union_access_index(), but not
preserve_array_access_index(). The debug info
is useful to identify the root type name which
later will be used for type comparison.

For user access without explicit type conversions,
the previous scheme works as we can ignore intermediate
compiler generated type conversions (e.g., from union types to
union members) and still generate correct access index string.

The issue comes with user explicit type conversions, e.g.,
converting an array to a structure like below:
  struct t { int a; char b[40]; };
  struct p { int c; int d; };
  struct t *var = ...;
  ... __builtin_preserve_access_index(&(((struct p *)&(var->b[0]))->d)) ...
Although BPF backend can derive the type of &(var->b[0]),
explicit type annotation make checking more consistent
and less error prone.

Another benefit is for multiple dimension array handling.
For example,
  struct p { int c; int d; } g[8][9][10];
  ... __builtin_preserve_access_index(&g[2][3][4].d) ...
It would be possible to calculate the number of "struct p"'s
before accessing its member "d" if array debug info is
available as it contains each dimension range.

This patch enables to annotate IR builtin preserve_array_access_index()
with proper debuginfo type. The unit test case and language reference
is updated as well.

Signed-off-by: Yonghong Song <yhs@fb.com>

Differential Revision: https://reviews.llvm.org/D65664

llvm-svn: 367724
2019-08-02 21:28:28 +00:00
Paul Robinson 89683e9dd7 [doc] Give a workaround for a FileCheck regex that ends in a brace.
Addresses PR42864.

llvm-svn: 367689
2019-08-02 16:07:48 +00:00
Lang Hames 809e9d1efa [ORC] Change the locking scheme for ThreadSafeModule.
ThreadSafeModule/ThreadSafeContext are used to manage lifetimes and locking
for LLVMContexts in ORCv2. Prior to this patch contexts were locked as soon
as an associated Module was emitted (to be compiled and linked), and were not
unlocked until the emit call returned. This could lead to deadlocks if
interdependent modules that shared contexts were compiled on different threads:
when, during emission of the first module, the dependence was discovered the
second module (which would provide the required symbol) could not be emitted as
the thread emitting the first module still held the lock.

This patch eliminates this possibility by moving to a finer-grained locking
scheme. Each client holds the module lock only while they are actively operating
on it. To make this finer grained locking simpler/safer to implement this patch
removes the explicit lock method, 'getContextLock', from ThreadSafeModule and
replaces it with a new method, 'withModuleDo', that implicitly locks the context,
calls a user-supplied function object to operate on the Module, then implicitly
unlocks the context before returning the result.

ThreadSafeModule TSM = getModule(...);
size_t NumFunctions = TSM.withModuleDo(
    [](Module &M) { // <- context locked before entry to lambda.
      return M.size();
    });

Existing ORCv2 layers that operate on ThreadSafeModules are updated to use the
new method.

This method is used to introduce Module locking into each of the existing
layers.

llvm-svn: 367686
2019-08-02 15:21:37 +00:00
Andrea Di Biagio 207e3af501 [MCA] Add support for printing immedate values as hex. Also enable lexing of masm binary and hex literals.
This patch adds a new llvm-mca flag named -print-imm-hex.

By default, the instruction printer prints immediate operands as decimals. Flag
-print-imm-hex enables the instruction printer to print those operands in hex.

This patch also adds support for MASM binary and hex literal numbers (example
0FFh, 101b).
Added tests to verify the behavior of the new flag. Tests also verify that masm
numeric literal operands are now recognized.

Differential Revision: https://reviews.llvm.org/D65588

llvm-svn: 367671
2019-08-02 10:38:25 +00:00
Matt Arsenault e56a2ad85e CodeGen: Allow virtual registers in bundles
The note in the documentation suggests this restriction is a compile
time optimization for architectures that make heavy use of
bundling. Allowing virtual registers in a bundle is useful for some
(non-R600) AMDGPU use cases and are infrequent enough to matter.

A more common AMDGPU use case has already been using virtual registers
in bundles since r333691, although never calling finalizeBundle on
them and manually creating the use/def list on the BUNDLE
instruction. This is also relatively infrequent, and only happens for
consecutive sequences of some load/store types.

llvm-svn: 367597
2019-08-01 18:41:28 +00:00
Erich Keane 441f119789 Fix spacing of LLVM_USE_PERF in CMake.rst that caused it to be tabbed in funny
llvm-svn: 367585
2019-08-01 17:30:25 +00:00
Erich Keane 1328cd0e37 Document LLVM_ENABLE_LIBCXX in CMake.rst
llvm-svn: 367584
2019-08-01 17:30:21 +00:00
Philip Reames c724215a70 Attempt to unbreak sphinx build bot by inserting a link.
llvm-svn: 367487
2019-07-31 22:14:26 +00:00
Lang Hames 001a554514 [docs] Add references to unreferenced footnotes.
Thanks to Stefan Granitz for catching the issue.

llvm-svn: 367458
2019-07-31 18:07:37 +00:00
Djordje Todorovic b9973f87c6 Reland "[DwarfDebug] Dump call site debug info"
The build failure found after the rL365467 has been
resolved.

Differential Revision: https://reviews.llvm.org/D60716

llvm-svn: 367446
2019-07-31 16:51:28 +00:00
Johannes Doerfert f7ef70501c [docs][FIX] Add missing word to documentation in terms of SCCs
In the approval of D65299, commited as rL367440, I mentioned that my
proposed wording was lacking the word "maximal". It is added now for
correctness.

llvm-svn: 367445
2019-07-31 16:48:42 +00:00
Anusha Basana f7fbd6cb9f [build] Add the ability to create a symlink for lipo
Add user enabled option to create lipo with symlink to llvm-lipo
Used rL326381 for reference.

Differential Revision: https://reviews.llvm.org/D65477

llvm-svn: 367444
2019-07-31 16:46:57 +00:00
Philip Reames f3b752365e [docs] Reword documentation in terms of SCCs not cycles
Given the example:
header:
  br i1 %c, label %next, label %header
next:
  br i1 %c2, label %exit, label %header

We end up with a loop containing both header and next.  Given that, the describing the loop in terms of cycles is confusing since we have multiple distinct cycles within a single Loop.  Standardize on the SCC to clarify.

Differential Revision: https://reviews.llvm.org/D65299

llvm-svn: 367440
2019-07-31 16:24:20 +00:00
Diana Picus 7117881fdb [docs] Add cmake to Software requirements
Add cmake to the list of packages required for compiling LLVM.
Also move make to the bottom of the list and mark it as optional.

Differential Revision: https://reviews.llvm.org/D65438

llvm-svn: 367395
2019-07-31 08:48:36 +00:00
JF Bastien e825b834ec [NFC] Remove LLVM_ALIGNAS
Summary: The minimum compilers support all have alignas, and we don't use LLVM_ALIGNAS anywhere anymore. This also removes an MSVC diagnostic which, according to the comment above, isn't relevant anymore.

Reviewers: rnk

Subscribers: mgorny, jkorous, dexonsmith, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D65458

llvm-svn: 367383
2019-07-31 03:22:08 +00:00
Francis Visoiu Mistrih 84e80979b5 Reland: [Remarks] Add an LLVM-bitstream-based remark serializer
Add a new serializer, using a binary format based on the LLVM bitstream
format.

This format provides a way to serialize the remarks in two modes:

1) Separate mode: the metadata is separate from the remark entries.
2) Standalone mode: the metadata and the remark entries are in the same
file.

The format contains:

* a meta block: container version, container type, string table,
external file path, remark version
* a remark block: type, remark name, pass name, function name, debug
file, debug line, debug column, hotness, arguments (key, value, debug
file, debug line, debug column)

A string table is required for this format, which will be dumped in the
meta block to be consumed before parsing the remark blocks.

On clang itself, we noticed a size reduction of 13.4x compared to YAML,
and a compile-time reduction of between 1.7% and 3.5% on CTMark.

Differential Revision: https://reviews.llvm.org/D63466

Original llvm-svn: 367364
Revert llvm-svn: 367370

llvm-svn: 367372
2019-07-31 00:13:51 +00:00
Francis Visoiu Mistrih d8e7967a22 Revert "[Remarks] Add an LLVM-bitstream-based remark serializer"
This reverts commit r367364.

Breaks some bots: http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-gn/builds/3161/steps/annotate/logs/stdio

llvm-svn: 367370
2019-07-31 00:01:34 +00:00
Francis Visoiu Mistrih 6c3c9483e7 [Remarks] Add an LLVM-bitstream-based remark serializer
Add a new serializer, using a binary format based on the LLVM bitstream
format.

This format provides a way to serialize the remarks in two modes:

1) Separate mode: the metadata is separate from the remark entries.
2) Standalone mode: the metadata and the remark entries are in the same
file.

The format contains:

* a meta block: container version, container type, string table,
external file path, remark version
* a remark block: type, remark name, pass name, function name, debug
file, debug line, debug column, hotness, arguments (key, value, debug
file, debug line, debug column)

A string table is required for this format, which will be dumped in the
meta block to be consumed before parsing the remark blocks.

On clang itself, we noticed a size reduction of 13.4x compared to YAML,
and a compile-time reduction of between 1.7% and 3.5% on CTMark.

Differential Revision: https://reviews.llvm.org/D63466

llvm-svn: 367364
2019-07-30 23:11:57 +00:00
Thomas Lively e0a9dce543 [WebAssembly] Do not emit tail calls with return type mismatch
Summary:
return_call and return_call_indirect are only valid if the return
types of the callee and caller match. We were previously not enforcing
that, which was producing invalid modules.

Reviewers: aheejin

Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65246

llvm-svn: 367339
2019-07-30 18:08:39 +00:00
Francis Visoiu Mistrih d9402ee03f [Docs] Fix sphinx warning in OCamlLangImpl5.rst
The path to the image was outdated.

http://lab.llvm.org:8011/builders/llvm-sphinx-docs/builds/33865/steps/docs-llvm-html/logs/stdio

llvm/docs/tutorial/OCamlLangImpl5.rst:173: WARNING: image file not readable: tutorial/LangImpl05-cfg.png

llvm-svn: 367334
2019-07-30 16:56:45 +00:00
Francis Visoiu Mistrih 5ed3d146f8 [Remarks] Add two serialization modes for remarks: separate and standalone
The default mode is separate, where the metadata is serialized
separately from the remarks.

Another mode is the standalone mode, where the metadata is serialized
before the remarks, on the same stream.

llvm-svn: 367328
2019-07-30 16:01:40 +00:00
Francis Visoiu Mistrih 64a5f9e112 Reland: [Remarks] Support parsing remark metadata in the YAML remark parser
This adds support to the yaml remark parser to be able to parse remarks
directly from the metadata.

This supports parsing separate metadata and following the external file
with the associated metadata, and also a standalone file containing
metadata + remarks all together.

Original llvm-svn: 367148
Revert llvm-svn: 367151

This has a fix for gcc builds.

llvm-svn: 367155
2019-07-26 21:02:02 +00:00
Francis Visoiu Mistrih cdc74e2197 Revert "[Remarks] Support parsing remark metadata in the YAML remark parser"
This reverts r367148.

Seems to fail on
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-fuzzer/builds/27768.

llvm-svn: 367151
2019-07-26 20:54:44 +00:00
Francis Visoiu Mistrih a41f61625a [Remarks] Support parsing remark metadata in the YAML remark parser
This adds support to the yaml remark parser to be able to parse remarks
directly from the metadata.

This supports parsing separate metadata and following the external file
with the associated metadata, and also a standalone file containing
metadata + remarks all together.

llvm-svn: 367148
2019-07-26 20:11:53 +00:00
Sergey Dmitriev cdeaac5dce [llvm-objcopy] Add support for --add-section for COFF
This patch enables support for --add-section=... option for COFF objects.

Differential Revision: https://reviews.llvm.org/D65040

llvm-svn: 367130
2019-07-26 17:06:41 +00:00
Sjoerd Meijer a48f58c97f [Clang] New loop pragma vectorize_predicate
This adds a new vectorize predication loop hint:

  #pragma clang loop vectorize_predicate(enable)

that can be used to indicate to the vectoriser that all (load/store)
instructions should be predicated (masked). This allows, for example, folding
of the remainder loop into the main loop.

This patch will be followed up with D64916 and D65197. The former is a
refactoring in the loopvectorizer and the groundwork to make tail loop folding
a more general concept, and in the latter the actual tail loop folding
transformation will be implemented.

Differential Revision: https://reviews.llvm.org/D64744

llvm-svn: 366989
2019-07-25 07:33:13 +00:00
Philip Reames 85fd8cea0b [docs] Split out a section on LoopInfo in the new loop documentation
llvm-svn: 366964
2019-07-24 23:46:13 +00:00
Philip Reames 904494944b Apply a few more reviewer suggestions from D65164
llvm-svn: 366961
2019-07-24 23:30:56 +00:00
Philip Reames 58b4787a22 Define some basic terminology around loops in our documentation
I've noticed a lot of confusion around this area recently with key terms being misused in a number of threads. To help reign that in, let's go ahead and document the current terminology and meaning thereof.

My hope is to grow this over time into a broader discussion of canonical loop forms - yes, there are more than one ... many more than one - but for the moment, simply having the key terminology is a good stopping place.

Note: I am landing this *without* an LGTM.  All feedback so far has been positive, and trying to apply all of the suggested changes/extensions would cause the review to never end.  Instead, I decided to land it with the obvious fixes made based on reviewer comments, then iterate from there.

Differential Revision: https://reviews.llvm.org/D65164

llvm-svn: 366960
2019-07-24 23:24:13 +00:00
Thomas Preud'homme 4cd9b853b5 FileCheck [8/12]: Define numeric var from expr
Summary:
This patch is part of a patch series to add support for FileCheck
numeric expressions. This specific patch lift the restriction for a
numeric expression to either be a variable definition or a numeric
expression to try to match.

This commit allows a numeric variable to be set to the result of the
evaluation of a numeric expression after it has been matched
successfully. When it happens, the variable is allowed to be used on
the same line since its value is known at match time.

It also makes use of this possibility to reuse the parsing code to
parse a command-line definition by crafting a mirror string of the
-D option with the equal sign replaced by a colon sign, e.g. for option
'-D#NUMVAL=10' it creates the string
'-D#NUMVAL=10 (parsed as [[#NUMVAL:10]])' where the numeric expression
is parsed to define NUMVAL. This result in a few tests needing updating
for the location diagnostics on top of the tests for the new feature.

It also enables empty numeric expression which match any number without
defining a variable. This is done here rather than in commit #5 of the
patch series because it requires to dissociate automatic regex insertion
in RegExStr from variable definition which would make commit #5 even
bigger than it already is.

Copyright:
    - Linaro (changes up to diff 183612 of revision D55940)
    - GraphCore (changes in later versions of revision D55940 and
                 in new revision created off D55940)

Reviewers: jhenderson, chandlerc, jdenny, probinson, grimar, arichardson, rnk

Subscribers: hiraditya, llvm-commits, probinson, dblaikie, grimar, arichardson, tra, rnk, kristina, hfinkel, rogfer01, JonChesterfield

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60388

> llvm-svn: 366860

llvm-svn: 366897
2019-07-24 12:38:22 +00:00
Thomas Preud'homme 5ecb880241 Revert "FileCheck [8/12]: Define numeric var from expr"
This reverts commit 1b05977538.

llvm-svn: 366872
2019-07-24 07:32:34 +00:00
Thomas Preud'homme 1b05977538 FileCheck [8/12]: Define numeric var from expr
Summary:
This patch is part of a patch series to add support for FileCheck
numeric expressions. This specific patch lift the restriction for a
numeric expression to either be a variable definition or a numeric
expression to try to match.

This commit allows a numeric variable to be set to the result of the
evaluation of a numeric expression after it has been matched
successfully. When it happens, the variable is allowed to be used on
the same line since its value is known at match time.

It also makes use of this possibility to reuse the parsing code to
parse a command-line definition by crafting a mirror string of the
-D option with the equal sign replaced by a colon sign, e.g. for option
'-D#NUMVAL=10' it creates the string
'-D#NUMVAL=10 (parsed as [[#NUMVAL:10]])' where the numeric expression
is parsed to define NUMVAL. This result in a few tests needing updating
for the location diagnostics on top of the tests for the new feature.

It also enables empty numeric expression which match any number without
defining a variable. This is done here rather than in commit #5 of the
patch series because it requires to dissociate automatic regex insertion
in RegExStr from variable definition which would make commit #5 even
bigger than it already is.

Copyright:
    - Linaro (changes up to diff 183612 of revision D55940)
    - GraphCore (changes in later versions of revision D55940 and
                 in new revision created off D55940)

Reviewers: jhenderson, chandlerc, jdenny, probinson, grimar, arichardson, rnk

Subscribers: hiraditya, llvm-commits, probinson, dblaikie, grimar, arichardson, tra, rnk, kristina, hfinkel, rogfer01, JonChesterfield

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60388

llvm-svn: 366860
2019-07-23 22:41:38 +00:00
Eli Friedman c69273fa10 [docs] Clarify where the indirect UB due to write-write races comes from
This is based on https://bugs.llvm.org/show_bug.cgi?id=42435#c3.

Patch by Ralf Jung.

llvm-svn: 366855
2019-07-23 21:51:26 +00:00
Francis Visoiu Mistrih c5b5cc4575 [Remarks] Introduce a new format: yaml-strtab
This exposes better support to use a string table with a format through
an actual new remark::Format, called yaml-strtab.

This can now be used with -fsave-optimization-record=yaml-strtab.

llvm-svn: 366849
2019-07-23 20:42:46 +00:00
Ryan Taylor 6f13637a3e [IR][Verifier] Allow IntToPtrInst to be !dereferenceable
Summary:
Allow IntToPtrInst to carry !dereferenceable metadata tag.
This is valid since !dereferenceable can be only be applied to
pointer type values.

Change-Id: If8a6e3c616f073d51eaff52ab74535c29ed497b4

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D64954

llvm-svn: 366826
2019-07-23 17:19:56 +00:00
Chris Lattner f688226bc9 unbreak links
llvm-svn: 366530
2019-07-19 05:49:11 +00:00
Chris Lattner 2e418e16dd replace the old kaleidoscope tutorial files with orphaned pages that forward to the new copy.
llvm-svn: 366529
2019-07-19 05:23:17 +00:00
Chris Lattner 8ef8e5686e Point to the dusted off version of the kaleidoscope tutorial.
llvm-svn: 366528
2019-07-19 05:15:57 +00:00
Jonas Devlieghere a5359b1b07 [CMake] Don't set Python_ADDITIONAL_VERSIONS
Until recently, Python_ADDITIONAL_VERSIONS was used to limit LLVM's
Python support to 2.7. Now that both LLVM and LLDB both support Python
3, there's no longer a need to put an arbitrary limit on this.

However, instead of removing the variable, r365692 expanded the list,
which has the (presumably unintentional) side-effect of expression
preference for Python 3.

Instead, as Michal proposed in the original code review, we should just
not set the list at all, and let CMake pick whatever Python interpreter
you have in your path.

This patch removes the Python_ADDITIONAL_VERSIONS variable in llvm,
clang and lld. I've also updated the docs with the default behavior and
how to force a different Python version to be used.

Differential revision: https://reviews.llvm.org/D64894

llvm-svn: 366447
2019-07-18 15:17:42 +00:00
Hans Wennborg 8f5b44aead Bump the trunk version to 10.0.0svn
and clear the release notes.

llvm-svn: 366427
2019-07-18 11:51:05 +00:00
Nathan Lanza 4f93b8b56f Fix typo in programmer's manual cantFile -> cantFail
llvm-svn: 366403
2019-07-18 05:24:22 +00:00
Lang Hames c23619b0c9 [ORC][docs] Fix an RST error: the code-block directive needs a newline after it.
llvm-svn: 366270
2019-07-16 21:41:43 +00:00
Lang Hames 607cd44bdc [ORC][docs] Trim ORCv1 to ORCv2 transition section, add a how-to section.
llvm-svn: 366269
2019-07-16 21:34:59 +00:00
Alex Brachet 2eacf69880 Revert [tools] [llvm-nm] Default to reading from stdin not a.out
This reverts r365889 (git commit 60c81354b1)

llvm-svn: 366219
2019-07-16 15:33:43 +00:00
Francis Visoiu Mistrih 94bad22c2c [Remarks] Simplify and refactor the RemarkParser interface
Before, everything was based on some kind of type erased parser
implementation which container a lot of boilerplate code when multiple
formats were to be supported.

This simplifies it by:

* the remark now owns its arguments
* *always* returning an error from the implementation side
* working around the way the YAML parser reports errors: catch them through
callbacks and re-insert them in a proper llvm::Error
* add a CParser wrapper that is used when implementing the C API to
avoid cluttering the C++ API with useless state
* LLVMRemarkParserGetNext now returns an object that needs to be
released to avoid leaking resources
* add a new API to dispose of a remark entry: LLVMRemarkEntryDispose

llvm-svn: 366217
2019-07-16 15:25:05 +00:00
Sylvestre Ledru 116e58e292 remove a duplicate declaration
llvm-svn: 366205
2019-07-16 12:05:54 +00:00
Sylvestre Ledru eea828054d Document the LLVM_ENABLE_BINDINGS option
llvm-svn: 366204
2019-07-16 11:59:17 +00:00
Evgeniy Stepanov c5e7f56249 ARM MTE stack sanitizer.
Add "memtag" sanitizer that detects and mitigates stack memory issues
using armv8.5 Memory Tagging Extension.

It is similar in principle to HWASan, which is a software implementation
of the same idea, but there are enough differencies to warrant a new
sanitizer type IMHO. It is also expected to have very different
performance properties.

The new sanitizer does not have a runtime library (it may grow one
later, along with a "debugging" mode). Similar to SafeStack and
StackProtector, the instrumentation pass (in a follow up change) will be
inserted in all cases, but will only affect functions marked with the
new sanitize_memtag attribute.

Reviewers: pcc, hctim, vitalybuka, ostannard

Subscribers: srhines, mehdi_amini, javed.absar, kristof.beyls, hiraditya, cryptoad, steven_wu, dexonsmith, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D64169

llvm-svn: 366123
2019-07-15 20:02:23 +00:00
Matt Arsenault 269e4e1b60 Add some release notes for 9.0 release
llvm-svn: 366093
2019-07-15 17:50:28 +00:00
James Henderson 73e3336809 [docs][llvm-nm] Fix inconsistent grammar
llvm-svn: 366080
2019-07-15 16:40:34 +00:00
Lang Hames a13cca41c5 [ORC] Start adding ORCv1 to ORCv2 transition tips to the ORCv2 doc.
llvm-svn: 366075
2019-07-15 15:36:37 +00:00
Dmitry Preobrazhensky 5153b1723a [AMDGPU][MC][GFX9][GFX10] Added support of GET_DOORBELL message
Reviewers: artem.tamazov, arsenm

Differential Revision: https://reviews.llvm.org/D64729

llvm-svn: 366071
2019-07-15 15:12:16 +00:00
Richard Sandiford ea36cdcec3 DeveloperPolicy: fix a typo
llvm-svn: 366046
2019-07-15 08:09:21 +00:00
Yonghong Song c3805d761e [BPF] add unit tests for preserve_{array,union,struct}_access_index intrinsics
This is a followup patch for https://reviews.llvm.org/D61810/new/,
which adds new intrinsics preserve_{array,union,struct}_access_index.

Currently, only BPF backend utilizes preserve_{array,union,struct}_access_index
intrinsics, so all tests are compiled with BPF target.

https://reviews.llvm.org/D61524 already added some tests for these
intrinsics, but some of them pretty complex.
This patch added a few unit test cases focusing on individual intrinsic
functions.

Also made a few clarification on language reference for these intrinsics.

Differential Revision: https://reviews.llvm.org/D64606

llvm-svn: 366038
2019-07-15 04:51:34 +00:00
Thomas Preud'homme 2a7f520460 FileCheck [7/12]: Arbitrary long numeric expressions
Summary:
This patch is part of a patch series to add support for FileCheck
numeric expressions. This specific patch extend numeric expression to
support an arbitrary number of operands, either variable or literals.

Copyright:
    - Linaro (changes up to diff 183612 of revision D55940)
    - GraphCore (changes in later versions of revision D55940 and
                 in new revision created off D55940)

Reviewers: jhenderson, chandlerc, jdenny, probinson, grimar, arichardson, rnk

Subscribers: hiraditya, llvm-commits, probinson, dblaikie, grimar, arichardson, tra, rnk, kristina, hfinkel, rogfer01, JonChesterfield

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60387

llvm-svn: 366001
2019-07-13 13:24:30 +00:00
Alex Brachet 60c81354b1 [tools] [llvm-nm] Default to reading from stdin not a.out
Summary: This moves away from defaulting to a.out and uses stdin only if stdin has a file redirected to it. This has been discussed on the llvm-dev mailing list [[ https://lists.llvm.org/pipermail/llvm-dev/2019-July/133642.html | here ]].

Reviewers: jhenderson, rupprecht, MaskRay, chrisjackson

Reviewed By: jhenderson, MaskRay

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D64290

llvm-svn: 365889
2019-07-12 10:20:01 +00:00
Djordje Todorovic 0739ccd3b5 Revert "[DwarfDebug] Dump call site debug info"
A build failure was found on the SystemZ platform.

This reverts commit 9e7e73578e54cd22b3c7af4b54274d743b6607cc.

llvm-svn: 365886
2019-07-12 09:45:12 +00:00
Tom Stellard ca39bb3880 docs/GithubMove.rst: Add link to GitHub migration status page
llvm-svn: 365865
2019-07-12 02:31:50 +00:00
Stefan Stipanovic 0626367202 [Attributor] Deduce "nosync" function attribute.
Introduce and deduce "nosync" function attribute to indicate that a function
does not synchronize with another thread in a way that other thread might free memory.

Reviewers: jdoerfert, jfb, nhaehnle, arsenm

Subscribers: wdng, hfinkel, nhaenhle, mehdi_amini, steven_wu,
dexonsmith, arsenm, uenoku, hiraditya, jfb, llvm-commits

Differential Revision: https://reviews.llvm.org/D62766

llvm-svn: 365830
2019-07-11 21:37:40 +00:00
Tom Stellard 14cb8c1c70 docs/GithubMove.rst: Remove obsolete information
Summary:
Remove references to the multirepo and update the document to
reflect the current state of the github repository.

Reviewers: mehdi_amini, jyknight

Subscribers: jdoerfert, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58420

llvm-svn: 365645
2019-07-10 15:39:37 +00:00
James Henderson 479c2188c1 [docs][llvm-symbolizer] Fix grammar
llvm-svn: 365630
2019-07-10 13:40:45 +00:00
James Henderson 666414254a [docs][llvm-dwarfdump] Normalise some wording
llvm-svn: 365603
2019-07-10 08:56:13 +00:00
Francis Visoiu Mistrih daf801bb11 [docs][Remarks] Add documentation for remarks in LLVM
This adds documentation that describes remarks in LLVM.

It aims at explaining what remarks are, how to enable them, and what
users can do with the different modes.

It lists all the available flags in LLVM (excluding clang), and
describes the expected YAML structure as well as the tools that support
the YAML format today.

Differential Revision: https://reviews.llvm.org/D64355

llvm-svn: 365578
2019-07-09 23:16:59 +00:00
Pavel Labath 9eb4b96be0 Add lldb type unit support to the release notes
Reviewers: JDevlieghere, teemperor

Subscribers: llvm-commits, lldb-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D64366

llvm-svn: 365568
2019-07-09 22:36:43 +00:00
Stanislav Mekhanoshin 22b2c3d651 [AMDGPU] gfx908 target
Differential Revision: https://reviews.llvm.org/D64429

llvm-svn: 365525
2019-07-09 18:10:06 +00:00
James Henderson e0a3ee79c5 [docs][llvm-dwarfdump] Fix wording
llvm-svn: 365489
2019-07-09 14:20:58 +00:00
James Henderson 8447b419a7 [docs][llvm-objdump] Make some wording improvements/simplifications.
llvm-svn: 365474
2019-07-09 12:41:39 +00:00
Djordje Todorovic 01eaae6dd1 [DwarfDebug] Dump call site debug info
Dump the DWARF information about call sites and call site parameters into
debug info sections.

The patch also provides an interface for the interpretation of instructions
that could load values of a call site parameters in order to generate DWARF
about the call site parameters.

([13/13] Introduce the debug entry values.)

Co-authored-by: Ananth Sowda <asowda@cisco.com>
Co-authored-by: Nikola Prica <nikola.prica@rt-rk.com>
Co-authored-by: Ivan Baev <ibaev@cisco.com>

Differential Revision: https://reviews.llvm.org/D60716

llvm-svn: 365467
2019-07-09 11:33:56 +00:00
James Henderson 65d7511f38 [docs][llvm-nm] Improve some wording
In particular, the --debug-syms switch really doesn't have anything to
do with debuggers, so I've updated the document accordingly.

llvm-svn: 365461
2019-07-09 10:40:50 +00:00
Simon Pilgrim 456fc4fa6d Retire VS2015 Support
As proposed here: https://lists.llvm.org/pipermail/llvm-dev/2019-June/133147.html

This patch raises the minimum supported version to build LLVM/Clang to Visual Studio 2017.

Differential Revision: https://reviews.llvm.org/D64326

llvm-svn: 365452
2019-07-09 10:10:48 +00:00
James Henderson 4363edb0e8 [docs][llvm-dwarfdump] Make some option descriptions clearer and more precise
Some of the wording in the doc (taken largely from the help text), was a
little imprecise in some cases, so this patch makes it a little more
precise.

Reviewed by: JDevlieghere, probinson

Differential Revision: https://reviews.llvm.org/D64332

llvm-svn: 365451
2019-07-09 10:03:12 +00:00
Yonghong Song e3919c6baf [BPF] add new intrinsics preserve_{array,union,struct}_access_index
For background of BPF CO-RE project, please refer to
  http://vger.kernel.org/bpfconf2019.html
In summary, BPF CO-RE intends to compile bpf programs
adjustable on struct/union layout change so the same
program can run on multiple kernels with adjustment
before loading based on native kernel structures.

In order to do this, we need keep track of GEP(getelementptr)
instruction base and result debuginfo types, so we
can adjust on the host based on kernel BTF info.
Capturing such information as an IR optimization is hard
as various optimization may have tweaked GEP and also
union is replaced by structure it is impossible to track
fieldindex for union member accesses.

Three intrinsic functions, preserve_{array,union,struct}_access_index,
are introducted.
  addr = preserve_array_access_index(base, index, dimension)
  addr = preserve_union_access_index(base, di_index)
  addr = preserve_struct_access_index(base, gep_index, di_index)
here,
  base: the base pointer for the array/union/struct access.
  index: the last access index for array, the same for IR/DebugInfo layout.
  dimension: the array dimension.
  gep_index: the access index based on IR layout.
  di_index: the access index based on user/debuginfo types.

For example, for the following example,
  $ cat test.c
  struct sk_buff {
     int i;
     int b1:1;
     int b2:2;
     union {
       struct {
         int o1;
         int o2;
       } o;
       struct {
         char flags;
         char dev_id;
       } dev;
       int netid;
     } u[10];
  };

  static int (*bpf_probe_read)(void *dst, int size, const void *unsafe_ptr)
      = (void *) 4;

  #define _(x) (__builtin_preserve_access_index(x))

  int bpf_prog(struct sk_buff *ctx) {
    char dev_id;
    bpf_probe_read(&dev_id, sizeof(char), _(&ctx->u[5].dev.dev_id));
    return dev_id;
  }
  $ clang -target bpf -O2 -g -emit-llvm -S -mllvm -print-before-all \
    test.c >& log

The generated IR looks like below:

  ...
  define dso_local i32 @bpf_prog(%struct.sk_buff*) #0 !dbg !15 {
    %2 = alloca %struct.sk_buff*, align 8
    %3 = alloca i8, align 1
    store %struct.sk_buff* %0, %struct.sk_buff** %2, align 8, !tbaa !45
    call void @llvm.dbg.declare(metadata %struct.sk_buff** %2, metadata !43, metadata !DIExpression()), !dbg !49
    call void @llvm.lifetime.start.p0i8(i64 1, i8* %3) #4, !dbg !50
    call void @llvm.dbg.declare(metadata i8* %3, metadata !44, metadata !DIExpression()), !dbg !51
    %4 = load i32 (i8*, i32, i8*)*, i32 (i8*, i32, i8*)** @bpf_probe_read, align 8, !dbg !52, !tbaa !45
    %5 = load %struct.sk_buff*, %struct.sk_buff** %2, align 8, !dbg !53, !tbaa !45
    %6 = call [10 x %union.anon]* @llvm.preserve.struct.access.index.p0a10s_union.anons.p0s_struct.sk_buffs(
         %struct.sk_buff* %5, i32 2, i32 3), !dbg !53, !llvm.preserve.access.index !19
    %7 = call %union.anon* @llvm.preserve.array.access.index.p0s_union.anons.p0a10s_union.anons(
         [10 x %union.anon]* %6, i32 1, i32 5), !dbg !53
    %8 = call %union.anon* @llvm.preserve.union.access.index.p0s_union.anons.p0s_union.anons(
         %union.anon* %7, i32 1), !dbg !53, !llvm.preserve.access.index !26
    %9 = bitcast %union.anon* %8 to %struct.anon.0*, !dbg !53
    %10 = call i8* @llvm.preserve.struct.access.index.p0i8.p0s_struct.anon.0s(
         %struct.anon.0* %9, i32 1, i32 1), !dbg !53, !llvm.preserve.access.index !34
    %11 = call i32 %4(i8* %3, i32 1, i8* %10), !dbg !52
    %12 = load i8, i8* %3, align 1, !dbg !54, !tbaa !55
    %13 = sext i8 %12 to i32, !dbg !54
    call void @llvm.lifetime.end.p0i8(i64 1, i8* %3) #4, !dbg !56
    ret i32 %13, !dbg !57
  }

  !19 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "sk_buff", file: !3, line: 1, size: 704, elements: !20)
  !26 = distinct !DICompositeType(tag: DW_TAG_union_type, scope: !19, file: !3, line: 5, size: 64, elements: !27)
  !34 = distinct !DICompositeType(tag: DW_TAG_structure_type, scope: !26, file: !3, line: 10, size: 16, elements: !35)

Note that @llvm.preserve.{struct,union}.access.index calls have metadata llvm.preserve.access.index
attached to instructions to provide struct/union debuginfo type information.

For &ctx->u[5].dev.dev_id,
  . The "%6 = ..." represents struct member "u" with index 2 for IR layout and index 3 for DI layout.
  . The "%7 = ..." represents array subscript "5".
  . The "%8 = ..." represents union member "dev" with index 1 for DI layout.
  . The "%10 = ..." represents struct member "dev_id" with index 1 for both IR and DI layout.

Basically, traversing the use-def chain recursively for the 3rd argument of bpf_probe_read() and
examining all preserve_*_access_index calls, the debuginfo struct/union/array access index
can be achieved.

The intrinsics also contain enough information to regenerate codes for IR layout.
For array and structure intrinsics, the proper GEP can be constructed.
For union intrinsics, replacing all uses of "addr" with "base" should be enough.

The test case ThinLTO/X86/lazyload_metadata.ll is adjusted to reflect the
new addition of the metadata.

Signed-off-by: Yonghong Song <yhs@fb.com>

Differential Revision: https://reviews.llvm.org/D61810

llvm-svn: 365423
2019-07-09 01:51:36 +00:00
Yonghong Song 0d566dbbae Revert "[BPF] add new intrinsics preserve_{array,union,struct}_access_index"
This reverts commit r365352.

Test ThinLTO/X86/lazyload_metadata.ll failed. Revert the commit
and at the same time to fix the issue.

llvm-svn: 365360
2019-07-08 17:47:43 +00:00
Dmitry Preobrazhensky 463b87ae88 [AMDGPU][MC][DOC] Updated AMD GPU assembler syntax description.
Corrected a typo.

llvm-svn: 365353
2019-07-08 17:09:09 +00:00
Yonghong Song 75c2a6709e [BPF] add new intrinsics preserve_{array,union,struct}_access_index
For background of BPF CO-RE project, please refer to
  http://vger.kernel.org/bpfconf2019.html
In summary, BPF CO-RE intends to compile bpf programs
adjustable on struct/union layout change so the same
program can run on multiple kernels with adjustment
before loading based on native kernel structures.

In order to do this, we need keep track of GEP(getelementptr)
instruction base and result debuginfo types, so we
can adjust on the host based on kernel BTF info.
Capturing such information as an IR optimization is hard
as various optimization may have tweaked GEP and also
union is replaced by structure it is impossible to track
fieldindex for union member accesses.

Three intrinsic functions, preserve_{array,union,struct}_access_index,
are introducted.
  addr = preserve_array_access_index(base, index, dimension)
  addr = preserve_union_access_index(base, di_index)
  addr = preserve_struct_access_index(base, gep_index, di_index)
here,
  base: the base pointer for the array/union/struct access.
  index: the last access index for array, the same for IR/DebugInfo layout.
  dimension: the array dimension.
  gep_index: the access index based on IR layout.
  di_index: the access index based on user/debuginfo types.

For example, for the following example,
  $ cat test.c
  struct sk_buff {
     int i;
     int b1:1;
     int b2:2;
     union {
       struct {
         int o1;
         int o2;
       } o;
       struct {
         char flags;
         char dev_id;
       } dev;
       int netid;
     } u[10];
  };

  static int (*bpf_probe_read)(void *dst, int size, const void *unsafe_ptr)
      = (void *) 4;

  #define _(x) (__builtin_preserve_access_index(x))

  int bpf_prog(struct sk_buff *ctx) {
    char dev_id;
    bpf_probe_read(&dev_id, sizeof(char), _(&ctx->u[5].dev.dev_id));
    return dev_id;
  }
  $ clang -target bpf -O2 -g -emit-llvm -S -mllvm -print-before-all \
    test.c >& log

The generated IR looks like below:

  ...
  define dso_local i32 @bpf_prog(%struct.sk_buff*) #0 !dbg !15 {
    %2 = alloca %struct.sk_buff*, align 8
    %3 = alloca i8, align 1
    store %struct.sk_buff* %0, %struct.sk_buff** %2, align 8, !tbaa !45
    call void @llvm.dbg.declare(metadata %struct.sk_buff** %2, metadata !43, metadata !DIExpression()), !dbg !49
    call void @llvm.lifetime.start.p0i8(i64 1, i8* %3) #4, !dbg !50
    call void @llvm.dbg.declare(metadata i8* %3, metadata !44, metadata !DIExpression()), !dbg !51
    %4 = load i32 (i8*, i32, i8*)*, i32 (i8*, i32, i8*)** @bpf_probe_read, align 8, !dbg !52, !tbaa !45
    %5 = load %struct.sk_buff*, %struct.sk_buff** %2, align 8, !dbg !53, !tbaa !45
    %6 = call [10 x %union.anon]* @llvm.preserve.struct.access.index.p0a10s_union.anons.p0s_struct.sk_buffs(
         %struct.sk_buff* %5, i32 2, i32 3), !dbg !53, !llvm.preserve.access.index !19
    %7 = call %union.anon* @llvm.preserve.array.access.index.p0s_union.anons.p0a10s_union.anons(
         [10 x %union.anon]* %6, i32 1, i32 5), !dbg !53
    %8 = call %union.anon* @llvm.preserve.union.access.index.p0s_union.anons.p0s_union.anons(
         %union.anon* %7, i32 1), !dbg !53, !llvm.preserve.access.index !26
    %9 = bitcast %union.anon* %8 to %struct.anon.0*, !dbg !53
    %10 = call i8* @llvm.preserve.struct.access.index.p0i8.p0s_struct.anon.0s(
         %struct.anon.0* %9, i32 1, i32 1), !dbg !53, !llvm.preserve.access.index !34
    %11 = call i32 %4(i8* %3, i32 1, i8* %10), !dbg !52
    %12 = load i8, i8* %3, align 1, !dbg !54, !tbaa !55
    %13 = sext i8 %12 to i32, !dbg !54
    call void @llvm.lifetime.end.p0i8(i64 1, i8* %3) #4, !dbg !56
    ret i32 %13, !dbg !57
  }

  !19 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "sk_buff", file: !3, line: 1, size: 704, elements: !20)
  !26 = distinct !DICompositeType(tag: DW_TAG_union_type, scope: !19, file: !3, line: 5, size: 64, elements: !27)
  !34 = distinct !DICompositeType(tag: DW_TAG_structure_type, scope: !26, file: !3, line: 10, size: 16, elements: !35)

Note that @llvm.preserve.{struct,union}.access.index calls have metadata llvm.preserve.access.index
attached to instructions to provide struct/union debuginfo type information.

For &ctx->u[5].dev.dev_id,
  . The "%6 = ..." represents struct member "u" with index 2 for IR layout and index 3 for DI layout.
  . The "%7 = ..." represents array subscript "5".
  . The "%8 = ..." represents union member "dev" with index 1 for DI layout.
  . The "%10 = ..." represents struct member "dev_id" with index 1 for both IR and DI layout.

Basically, traversing the use-def chain recursively for the 3rd argument of bpf_probe_read() and
examining all preserve_*_access_index calls, the debuginfo struct/union/array access index
can be achieved.

The intrinsics also contain enough information to regenerate codes for IR layout.
For array and structure intrinsics, the proper GEP can be constructed.
For union intrinsics, replacing all uses of "addr" with "base" should be enough.

Signed-off-by: Yonghong Song <yhs@fb.com>

Differential Revision: https://reviews.llvm.org/D61810

llvm-svn: 365352
2019-07-08 17:08:28 +00:00
Dmitry Preobrazhensky cef9d42157 [AMDGPU][MC][DOC] Updated AMD GPU assembler syntax description.
Summary of changes:
- added description of GFX10;
- added description of operands sccz, vccz, lds_direct, etc;
- minor bugfixing and improvements.

llvm-svn: 365347
2019-07-08 16:50:11 +00:00
Brian Homerding b4b21d807e Add, and infer, a nofree function attribute
This patch adds a function attribute, nofree, to indicate that a function does
not, directly or indirectly, call a memory-deallocation function (e.g., free,
C++'s operator delete).

Reviewers: jdoerfert

Differential Revision: https://reviews.llvm.org/D49165

llvm-svn: 365336
2019-07-08 15:57:56 +00:00
James Henderson b52a0c0cc8 [docs][llvm-readobj][llvm-readelf] Improve wording
llvm-svn: 365335
2019-07-08 15:46:26 +00:00
Joel E. Denny 1602058c04 [lit] Parse command-line options from LIT_OPTS
Similar to `FILECHECK_OPTS` for FileCheck, `LIT_OPTS` makes it easy to
adjust lit behavior when running the test suite via ninja.  For
example:

```
$ LIT_OPTS='--time-tests -vv --filter=threadprivate' \
  ninja check-clang-openmp
```

Reviewed By: probinson

Differential Revision: https://reviews.llvm.org/D64135

llvm-svn: 365313
2019-07-08 12:18:40 +00:00
James Henderson 8cf99a1170 [docs][llvm-objcopy] Add description of binary input/output to doc
We briefly referred to being able to specify --target=binary without
explaining what binary input/output meant. This change adds a section on
this.

Reviewed by: MaskRay, abrachet

Differential Revision: https://reviews.llvm.org/D64245

llvm-svn: 365312
2019-07-08 11:41:54 +00:00
Jonas Devlieghere 7626e1e504 Add lldb-mi deprecation to the release notes
Differential revision: https://reviews.llvm.org/D64254

llvm-svn: 365231
2019-07-05 18:23:52 +00:00
Jonas Devlieghere bb65a38b56 Add LLDB section to the release notes
llvm-svn: 365228
2019-07-05 17:58:30 +00:00
James Henderson 9e38f510b3 [docs][llvm-readobj] Add a note to options that do nothing in GNU output
--section-data, --section-relocations and --section-symbols have no
effect for GNU style ouput. This patch changes the docs to point this
out, as it has caught me out on a couple of occasions.

See also https://bugs.llvm.org/show_bug.cgi?id=42522.

llvm-svn: 365221
2019-07-05 16:38:52 +00:00
Yaxun Liu a62413526d [AMDGPU] Added a new metadata for multi grid sync implicit argument
Patch by Christudasan Devadasan.

Differential Revision: https://reviews.llvm.org/D63886

llvm-svn: 365217
2019-07-05 16:05:17 +00:00
Graham Hunter 957c40db6a Scalable Vector IR Type with further LTO fixes
Reintroduces the scalable vector IR type from D32530, after it was reverted
a couple of times due to increasing chromium LTO build times. This latest
incarnation removes the walk over aggregate types from the verifier entirely,
in favor of rejecting scalable vectors in the isValidElementType methods in
ArrayType and StructType. This removes the 70% degradation observed with
the second repro tarball from PR42210.

Reviewers: thakis, hans, rengolin, sdesmalen

Reviewed By: sdesmalen

Differential Revision: https://reviews.llvm.org/D64079

llvm-svn: 365203
2019-07-05 12:48:16 +00:00
James Henderson 1a517a4630 [docs][llvm-objcopy] Improve some wording.
llvm-svn: 365187
2019-07-05 11:57:07 +00:00
Alex Brachet 09a066b3aa [docs] [tools] Fix see also links
Summary: Changes "see also" links to use :manpage: instead of plain text or the form `name|name` which was being treated literally, not as a link.

Reviewers: jhenderson, rupprecht

Reviewed By: jhenderson

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D63970

llvm-svn: 365159
2019-07-04 21:19:05 +00:00
Serge Guelton 85fc597f26 Document legacy pass manager extension points
Differential Revision: https://reviews.llvm.org/D64093

llvm-svn: 365142
2019-07-04 14:03:11 +00:00
James Henderson 38d9903826 [docs][llvm-dwarfdump] Remove unnecessary reference to --show-children
The --show-children option description describes what it does, and
references the =<offset> parameter of section dump switches. I don't
think it needs to be explained again in the documentation of the
section dump switches too.

Reviewed by: JDevlieghere

Differential Revision: https://reviews.llvm.org/D64132

llvm-svn: 365115
2019-07-04 08:49:04 +00:00
Alex Brachet fa9d232e43 [docs] [NFC] Removed excess spacing
Summary: Removed excess new lines from documentations. As far as I can tell, it seems as though restructured text is agnostic to new lines, the use of new lines was inconsistent and had no effect on how the files were being displayed.

Reviewers: jhenderson, rupprecht, JDevlieghere

Reviewed By: jhenderson

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D63971

llvm-svn: 365105
2019-07-04 04:41:06 +00:00
James Henderson e26ca966fb [docs][llvm-objcopy] Write documentation for llvm-objcopy
This patch addresses https://bugs.llvm.org/show_bug.cgi?id=42183 by replacing
the stub markdown doc for llvm-objcopy with a full one describing the current
options available in llvm-objcopy.

Reviewed by: jakehehrlich, MaskRay

Differential Revision: https://reviews.llvm.org/D63820

llvm-svn: 365042
2019-07-03 14:21:48 +00:00
Sven van Haastregt 1bc2cccf18 Remove some autoconf references from docs and comments
The autoconf build system support has been removed a while ago, remove
some outdated references.

Differential Revision: https://reviews.llvm.org/D63608

llvm-svn: 365013
2019-07-03 09:57:59 +00:00
James Henderson aef4cec96b [docs][llvm-readelf] Delete old llvm-readelf.md
This was accidentally missed when committing r364800.

llvm-svn: 364918
2019-07-02 13:11:34 +00:00
James Henderson 90c57e0001 [docs][llvm-readelf] Expand llvm-readelf documentation
Previously, the llvm-readelf documentation was essentially just a list
of differences to llvm-readobj. Since llvm-readelf is the more likely
goto tool for many people migrating to the LLVM toolchain, it seems like
it would be helpful to document all the switches in the llvm-readelf
document too. This change expands the options listed accordingly.
Additionally, they are unlikely to care what the differences are to
llvm-readobj, since they won't be familiar with the latter as there is
no GNU equivalent, so this change moves the "differences" section to
llvm-readobj's documentation.

Reviewed by: peter.smith

Differential Revision: https://reviews.llvm.org/D63826

llvm-svn: 364800
2019-07-01 16:18:57 +00:00
Amara Emerson 4fcf0004fa [LangRef] Clarify codegen expectations for intrinsics with fp/integer-only overloads.
This change is a result of discussions on list: "GlobalISel: Ambiguous intrinsic semantics problem"

Differential Revision: https://reviews.llvm.org/D59657

llvm-svn: 364610
2019-06-27 23:33:05 +00:00
Yuanfang Chen 2dcd2c2493 [llvm-objdump] Update the doc for --disassemble-functions.
Update the doc after llvm-svn: 364121 is landed.
With two more trivial fixes that are not related to
--disassemble-functions but still about llvm-objdump.

Reviewers: jhenderson, grimar, MaskRay, rupprecht, peter.smith

Reviewed by: jhenderson, MaskRay

Differential Revision: https://reviews.llvm.org/D63787

llvm-svn: 364573
2019-06-27 18:39:34 +00:00
Johannes Doerfert 3b77583e95 [Attr] Add "willreturn" function attribute
This patch introduces a new function attribute, willreturn, to indicate
that a call of this function will either exhibit undefined behavior or
comes back and continues execution at a point in the existing call stack
that includes the current invocation.

This attribute guarantees that the function does not have any endless
loops, endless recursion, or terminating functions like abort or exit.

Patch by Hideto Ueno (@uenoku)

Reviewers: jdoerfert

Subscribers: mehdi_amini, hiraditya, steven_wu, dexonsmith, lebedev.ri, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D62801

llvm-svn: 364555
2019-06-27 15:51:40 +00:00
James Henderson 92b32a9087 [docs][llvm-nm][llvm-objdump] Improve "See Also" section
The "See Also" section for llvm-nm didn't actually contain any links,
and the tools referred to didn't make much sense (referring to non-LLVM
tools, when we have equivalents, or tools that aren't really to do with
symbol dumping). llvm-objdump's didn't refer to llvm-readelf.

Reviewed by: grimar

Differential Revision: https://reviews.llvm.org/D63875

llvm-svn: 364552
2019-06-27 15:18:15 +00:00
Hans Wennborg 408fc0849e Revert r363658 "[SVE][IR] Scalable Vector IR Type with pr42210 fix"
We saw a 70% ThinLTO link time increase in Chromium for Android, see
crbug.com/978817. Sounds like more of PR42210.

> Recommit of D32530 with a few small changes:
>   - Stopped recursively walking through aggregates in
>     the verifier, so that we don't impose too much
>     overhead on large modules under LTO (see PR42210).
>   - Changed tests to match; the errors are slightly
>     different since they only report the array or
>     struct that actually contains a scalable vector,
>     rather than all aggregates which contain one in
>     a nested member.
>   - Corrected an older comment
>
> Reviewers: thakis, rengolin, sdesmalen
>
> Reviewed By: sdesmalen
>
> Differential Revision: https://reviews.llvm.org/D63321

llvm-svn: 364543
2019-06-27 13:55:02 +00:00
Djordje Todorovic a0d45058eb [DWARF] Handle the DW_OP_entry_value operand
Add the IR and the AsmPrinter parts for handling of the DW_OP_entry_values
DWARF operation.

([11/13] Introduce the debug entry values.)

Co-authored-by: Ananth Sowda <asowda@cisco.com>
Co-authored-by: Nikola Prica <nikola.prica@rt-rk.com>
Co-authored-by: Ivan Baev <ibaev@cisco.com>

Differential Revision: https://reviews.llvm.org/D60866

llvm-svn: 364542
2019-06-27 13:52:34 +00:00
James Henderson a056684c33 [docs][tools] Add missing "program" tags to rst files
Sphinx allows for definitions of command-line options using
`.. option <name>` and references to those options via `:option:<name>`.
However, it looks like there is no scoping of these options by default,
meaning that links can end up pointing to incorrect documents. See for
example the llvm-mca document, which contains references to -o that,
prior to this patch, pointed to a different document. What's worse is
that these links appear to be non-deterministic in which one is picked
(on my machine, some references end up pointing to opt, whereas on the
live docs, they point to llvm-dwarfdump, for example).

The fix is to add the .. program <name> tag. This essentially namespaces
the options (definitions and references) to the named program, ensuring
that the links are kept correct.

Reviwed by: andreadb

Differential Revision: https://reviews.llvm.org/D63873

llvm-svn: 364538
2019-06-27 13:24:46 +00:00
Djordje Todorovic a7cde103c1 [MachineFunction] Base support for call site info tracking
Add an attribute into the MachineFunction that tracks call site info.

([8/13] Introduce the debug entry values.)

Co-authored-by: Ananth Sowda <asowda@cisco.com>
Co-authored-by: Nikola Prica <nikola.prica@rt-rk.com>
Co-authored-by: Ivan Baev <ibaev@cisco.com>

Differential Revision: https://reviews.llvm.org/D61061

llvm-svn: 364506
2019-06-27 07:48:06 +00:00
Djordje Todorovic 59b39faa18 [IR] Add DISuprogram and DIE for a func decl
A unique DISubprogram may be attached to a function declaration used for
call site debug info.

([6/13] Introduce the debug entry values.)

Co-authored-by: Ananth Sowda <asowda@cisco.com>
Co-authored-by: Nikola Prica <nikola.prica@rt-rk.com>
Co-authored-by: Ivan Baev <ibaev@cisco.com>

Differential Revision: https://reviews.llvm.org/D60713

llvm-svn: 364500
2019-06-27 06:07:41 +00:00
Thomas Lively a1d97a960e [WebAssembly] Implement tail calls and unify tablegen call classes
Summary:
Implements direct and indirect tail calls enabled by the 'tail-call'
feature in both DAG ISel and FastISel. Updates existing call tests and
adds new tests including a binary encoding test.

Reviewers: aheejin

Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D62877

llvm-svn: 364445
2019-06-26 16:17:15 +00:00
James Henderson 512c52513e [docs][llvm-symbolizer] Improve llvm-symbolizer documentation
As detailed in https://bugs.llvm.org/show_bug.cgi?id=42253, there were a
number of issues in the llvm-symbolizer documentation. This patch fixes
them by:

 1. Adding [addresses...] to the synopsis, and matching the formatting
    of other tools.
 2. Rewriting the description to fix grammar issues and mention other
    usage options.
 3. Rewriting the examples to be easier to read.
 4. Re-ordering the options into alphabetical order.
 5. Improving the text of some of the option descriptions, and adding
    some examples to individual options.
 6. Splitting the Mach-O options into a separate section of the
    document.
 7. Standardizing on double dashes for long options throughout the file.
 8. Adding a reference to the llvm-addr2line document.

Reviewed by: mtrent, ikudrin

Differential Revision: https://reviews.llvm.org/D63651

llvm-svn: 364410
2019-06-26 11:42:03 +00:00
Djordje Todorovic e821e79fce [IR/DIVar] Add the flag for params that have unmodified value
Introduce the debug info flag that indicates that a parameter has unchanged
value throughout a function. This info will be used to emit the expressions
with DW_OP_entry_value.

([4/13] Introduce the debug entry values.)

Co-authored-by: Ananth Sowda <asowda@cisco.com>
Co-authored-by: Nikola Prica <nikola.prica@rt-rk.com>
Co-authored-by: Ivan Baev <ibaev@cisco.com>

Differential Revision: https://reviews.llvm.org/D58034

llvm-svn: 364406
2019-06-26 11:19:26 +00:00
Simon Tatham e8de8ba6a6 [ARM] Support inline assembler constraints for MVE.
"To" selects an odd-numbered GPR, and "Te" an even one. There are some
8.1-M instructions that have one too few bits in their register fields
and require registers of particular parity, without necessarily using
a consecutive even/odd pair.

Also, the constraint letter "t" should select an MVE q-register, when
MVE is present. This didn't need any source changes, but some extra
tests have been added.

Reviewers: dmgreen, samparker, SjoerdMeijer

Subscribers: javed.absar, eraman, kristof.beyls, hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D60709

llvm-svn: 364331
2019-06-25 16:49:32 +00:00
Kevin P. Neal d0f96be2c7 [FPEnv] A missing crucial step was undocumented.
llvm-svn: 364328
2019-06-25 16:09:39 +00:00
James Henderson b96d9d8bda [docs][llvm-readobj] Improve llvm-readobj documentation
There were a number of issues with the llvm-readobj documentation. The
following points were raised in https://bugs.llvm.org/show_bug.cgi?id=42255,
and have been fixed in this patch:

 1. The description section claimed "The tool and its output is
    primarily designed for use in FileCheck-based tests" which is not
    really the case any more.
 2. The documentation used single-dash long options for option names,
    but references in the help text to other options exclusively used
    double-dashes. Fixed by standardising on double-dashes for all
    long-form options.
 3. The majority of options available and in the help text were not
    present in the documentation. This patch adds them.
 4. Several aliases, both long and short, were missing, e.g. --relocs.

Additionally, this patch improves the documentation by:

 1. Splitting the options into categories based on the file format they
    are specific to.
 2. Updating the Exit Status section to correctly mention that errors
    lead to a non-zero exit code.
 3. Adding a See Also section referencing other similar LLVM tools.
 4. Improving/correcting some of the descriptions of options that did
    not quite match up with what llvm-readobj does.

Reviewed by: peter.smith, MaskRay, mtrent

Differential Revision: https://reviews.llvm.org/D63719

llvm-svn: 364306
2019-06-25 13:12:38 +00:00
Nicolai Haehnle 08e8cb5760 AMDGPU/MC: Add .amdgpu_lds directive
Summary:
The directive defines a symbol as an group/local memory (LDS) symbol.
LDS symbols behave similar to common symbols for the purposes of ELF,
using the processor-specific SHN_AMDGPU_LDS as section index.

It is the linker and/or runtime loader's job to "instantiate" LDS symbols
and resolve relocations that reference them.

It is not possible to initialize LDS memory (not even zero-initialize
as for .bss).

We want to be able to link together objects -- starting with relocatable
objects, but possible expanding to shared objects in the future -- that
access LDS memory in a flexible way.

LDS memory is in an address space that is entirely separate from the
address space that contains the program image (code and normal data),
so having program segments for it doesn't really make sense.

Furthermore, we want to be able to compile multiple kernels in a
compilation unit which have disjoint use of LDS memory. In that case,
we may want to place LDS symbols differently for different kernels
to save memory (LDS memory is very limited and physically private to
each kernel invocation), so we can't simply place LDS symbols in a
.lds section.

Hence this solution where LDS symbols always stay undefined.

Change-Id: I08cbc37a7c0c32f53f7b6123aa0afc91dbc1748f

Reviewers: arsenm, rampitec, t-tye, b-sumner, jsjodin

Subscribers: kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, rupprecht, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D61493

llvm-svn: 364296
2019-06-25 11:51:35 +00:00
James Henderson ecd9348aa1 [docs][llvm-cxxfilt] Write llvm-cxxfilt documentation
There was a stub for llvm-cxxfilt, but it didn't describe the options.
Additionally, it was in markdown, which was causing issues, so as
discussed in https://reviews.llvm.org/D63211, this change replaces the
existing stub with an RST file.

Reviewed by: MaskRay, mattd

Differential Revision: https://reviews.llvm.org/D63722

llvm-svn: 364287
2019-06-25 10:36:15 +00:00
Hiroshi Inoue 78edad1bf1 [NFC] fix trivial typos in documents
llvm-svn: 364278
2019-06-25 07:24:27 +00:00
James Henderson 2c5ff94627 [docs][llvm-nm] Add missing options to documentation
There were several options missing from the documentation. This patch
adds them as well as improving some wording and separating the Mach-O
only options into a separate section.

Fixes https://bugs.llvm.org/show_bug.cgi?id=42234.

Reviewed by: MaskRay

Differential Revision: https://reviews.llvm.org/D63655

llvm-svn: 364176
2019-06-24 10:50:49 +00:00
James Henderson 3519d5535a [docs][llvm-nm] Improve symbol code documentation
The existing symbol code documentation was very incomplete. This patch
adds the missing codes, and defines them based on the current code
behaviour.

Fixes https://bugs.llvm.org/show_bug.cgi?id=42231.

Reviewed by: rupprecht, mtrent, MaskRay

Differential Revision: https://reviews.llvm.org/D63327

llvm-svn: 364171
2019-06-24 09:53:02 +00:00
Nico Weber ae02f6b594 PDB docs: Delete trailing whitespace, wrap to 80 cols
llvm-svn: 364131
2019-06-22 11:23:01 +00:00
James Henderson f7212dbe2f [docs][llvm-objdump] Fix bad merge of docs
llvm-svn: 364056
2019-06-21 14:41:36 +00:00
James Henderson 9485b265e8 [binutils] Add response file option to help and docs
Many LLVM-based tools already support response files (i.e. files
containing a list of options, specified with '@'). This change simply
updates the documentation and help text for some of these tools to
include it. I haven't attempted to fix all tools, just a selection that
I am interested in.

I've taken the opportunity to add some tests for --help behaviour, where
they were missing. We could expand these tests, but I don't think that's
within scope of this patch.

This fixes https://bugs.llvm.org/show_bug.cgi?id=42233 and
https://bugs.llvm.org/show_bug.cgi?id=42236.

Reviewed by: grimar, MaskRay, jkorous

Differential Revision: https://reviews.llvm.org/D63597

llvm-svn: 364036
2019-06-21 11:49:20 +00:00
James Henderson a8ed354b64 [docs][llvm-objdump] Improve llvm-objdump documentation
The llvm-objdump document was missing many options, and there were also
some style issues with it. This patches fixes all but the first issue
listed in https://bugs.llvm.org/show_bug.cgi?id=42249 by:

    1. Adding missing options and commands.
    2. Standardising on double dashes for long-options throughout.
    3. Moving Mach-O specific options to a separate section.
    4. Removing options that don't exist or aren't relevant to
       llvm-objdump.

Reviewed by: MaskRay, mtrent, alexshap

Differential Revision: https://reviews.llvm.org/D63606

llvm-svn: 364019
2019-06-21 10:12:53 +00:00
Thomas Preud'homme a2ef1ba32f [FileCheck] Stop qualifying expressions as numeric
Summary:
Stop referring to "numeric expression", using simply the term
"expression" instead. Likewise for numeric operation since operations
are only used in numeric expressions.

Reviewers: jhenderson, jdenny, probinson, arichardson

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D63500

llvm-svn: 363901
2019-06-19 23:47:24 +00:00
Andrea Di Biagio 792510f869 [llvm-mca][docs] clarify how the quality of the perf report is affected by the quality of the scheduling models.
Differential Revision: https://reviews.llvm.org/D63556

llvm-svn: 363830
2019-06-19 16:10:58 +00:00
Graham Hunter 43854e3ccc [SVE][IR] Scalable Vector IR Type with pr42210 fix
Recommit of D32530 with a few small changes:
  - Stopped recursively walking through aggregates in
    the verifier, so that we don't impose too much
    overhead on large modules under LTO (see PR42210).
  - Changed tests to match; the errors are slightly
    different since they only report the array or
    struct that actually contains a scalable vector,
    rather than all aggregates which contain one in
    a nested member.
  - Corrected an older comment

Reviewers: thakis, rengolin, sdesmalen

Reviewed By: sdesmalen

Differential Revision: https://reviews.llvm.org/D63321

llvm-svn: 363658
2019-06-18 10:11:56 +00:00
Jeremy Morse a1a4f5f12c [DebugInfo][Docs] Document that prologue/epilogue variable location changes are ignored
This patch documents that LLVM does not describe all changes in variable
locations during the prologue and the epilogue. The debugger doesn't /
shouldn't step through that portion of the function anyway, and describing
every location through such stages would bloat location lists.

Perform some minor cleanup at the same time,
 * Fix an enumerated list
 * Document that dbg.declare intrinsics have their variable location recorded
   in a MachineFunction table, not with DBG_VALUE meta-insts
 * Adds frame-indexes to the list of things that can be operands to
   DBG_VALUEs.

Differential Revision: https://reviews.llvm.org/D63083

llvm-svn: 363654
2019-06-18 08:52:38 +00:00
Peter Collingbourne fb9ce100d1 hwasan: Add a tag_offset DWARF attribute to instrumented stack variables.
The goal is to improve hwasan's error reporting for stack use-after-return by
recording enough information to allow the specific variable that was accessed
to be identified based on the pointer's tag. Currently we record the PC and
lower bits of SP for each stack frame we create (which will eventually be
enough to derive the base tag used by the stack frame) but that's not enough
to determine the specific tag for each variable, which is the stack frame's
base tag XOR a value (the "tag offset") that is unique for each variable in
a function.

In IR, the tag offset is most naturally represented as part of a location
expression on the llvm.dbg.declare instruction. However, the presence of the
tag offset in the variable's actual location expression is likely to confuse
debuggers which won't know about tag offsets, and moreover the tag offset
is not required for a debugger to determine the location of the variable on
the stack, so at the DWARF level it is represented as an attribute so that
it will be ignored by debuggers that don't know about it.

Differential Revision: https://reviews.llvm.org/D63119

llvm-svn: 363635
2019-06-17 23:39:41 +00:00
James Henderson 891cdaab7a [docs][llvm-dwarfdump] Make the --show-parents and --show-children help text and docs more consistent and correct
The docs and help text for --show-parents and --show-children were a bit
inconsistent. The help text claimed they had an effect when "=<offset>"
was used, whereas the doc said it had an effect when "--find" or
"--name" were used. This change changes the doc to mention "=<offset>"
and removes this reference from the help text, to avoid having a very
long description in the help text (it still says "when selectively
printing entries").

Reviewed by: JDevlieghere, aprantl

Differential Revision: https://reviews.llvm.org/D63275

llvm-svn: 363380
2019-06-14 13:00:09 +00:00
Stanislav Mekhanoshin 4336a9496d [AMDGPU] gfx10 documentation update. NFC.
llvm-svn: 363332
2019-06-13 22:18:47 +00:00
Vedant Kumar 901d04fc6d [Coverage] Load code coverage data from archives
Support loading code coverage data from regular archives, thin archives,
and from MachO universal binaries which contain archives.

Testing: check-llvm, check-profile (with {A,UB}San enabled)

rdar://51538999

Differential Revision: https://reviews.llvm.org/D63232

llvm-svn: 363325
2019-06-13 20:48:57 +00:00
Nikita Popov ad81d427ca [LangRef] Clarify poison semantics
I find the current documentation of poison somewhat confusing,
mainly because its use of "undefined behavior" doesn't seem to
align with our usual interpretation (of immediate UB). Especially
the sentence "any instruction that has a dependence on a poison
value has undefined behavior" is very confusing.

Clarify poison semantics by:

 * Replacing the introductory paragraph with the standard rationale
   for having poison values.
 * Spelling out that instructions depending on poison return poison.
 * Spelling out how we go from a poison value to immediate undefined
   behavior and give the two examples we currently use in ValueTracking.
 * Spelling out that side effects depending on poison are UB.

Differential Revision: https://reviews.llvm.org/D63044

llvm-svn: 363320
2019-06-13 19:45:36 +00:00
Jordan Rupprecht 4244dd5e3f [docs] Fix TableGen/LangRef typos
This fixes:
 - `Pred` -> `Prep`
 - `IfDef` -> `Ifdef` (rst is case sensitive here)

llvm-svn: 363294
2019-06-13 18:42:30 +00:00
James Henderson e6820dac99 [docs][llvm-symbolizer] Fix formatting issue with --functions
Reviewed by: rupprecht

Differential Revision: https://reviews.llvm.org/D63195

llvm-svn: 363266
2019-06-13 13:58:44 +00:00
James Henderson 86b510aa58 [docs][llvm-dwarfdump] Add missing options and behaviour to documentation
This fixes https://bugs.llvm.org/show_bug.cgi?id=42185.

llvm-dwarfdump's documentation was missing a number of options and other
behaviours. This change tries to fix up the documentation by adding
these missing items.

Reviewed by: JDevlieghere

Differential Revision: https://reviews.llvm.org/D63217

llvm-svn: 363264
2019-06-13 13:53:16 +00:00
Sander de Smalen 51c2fa0e2a Improve reduction intrinsics by overloading result value.
This patch uses the mechanism from D62995 to strengthen the
definitions of the reduction intrinsics by letting the scalar
result/accumulator type be overloaded from the vector element type.

For example:

  ; The LLVM LangRef specifies that the scalar result must equal the
  ; vector element type, but this is not checked/enforced by LLVM.
  declare i32 @llvm.experimental.vector.reduce.or.i32.v4i32(<4 x i32> %a)

This patch changes that into:

  declare i32 @llvm.experimental.vector.reduce.or.v4i32(<4 x i32> %a)

Which has the type-constraint more explicit and causes LLVM to check
the result type with the vector element type.

Reviewers: RKSimon, arsenm, rnk, greened, aemerson

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D62996

llvm-svn: 363240
2019-06-13 09:37:38 +00:00
Shoaib Meenai 8f4973f57b [llvm-lipo] Update llvm-lipo docs for -archs flag
The information for -archs flag is added to llvm-lipo.rst.

Patch by Anusha Basana <anusha.basana@gmail.com>

Differential Revision: https://reviews.llvm.org/D63100

llvm-svn: 363182
2019-06-12 17:37:01 +00:00
James Henderson 31908669c6 [docs][llvm-symbolizer] Fix typo and grammar error
llvm-svn: 363145
2019-06-12 11:41:43 +00:00
Xing GUO 7a15e99f3a [DOC] Fix `load` instructions' syntax, function definition.
Summary: In this patch, I updated `load` instruction syntax and fixed function definition. Besides, I re-named some variables to make them obey SSA rule.

Reviewers: MaskRay

Reviewed By: MaskRay

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D63186

llvm-svn: 363142
2019-06-12 11:24:22 +00:00
James Henderson 4cfcacbdfe [docs] Fix typo
llvm-svn: 363138
2019-06-12 10:48:33 +00:00
James Henderson 2c16bb8034 [llvm-nm] Fix docs and help text for --print-size
The --print-size help text and documentation claimed that the size was
printed instead of the address, but this is incorrect. It is printed as
well as the address. This patch fixes this issue.

Reviewed by: MaskRay, mtrent, ruiu

Differential Revision: https://reviews.llvm.org/D63142

llvm-svn: 363136
2019-06-12 10:44:41 +00:00
Jordan Rupprecht 4c3722aea8 [docs] Add "GNU binutils Replacements" section to command guide
Summary:
This splits out a section in the command guide for llvm tools that can be used as replacements for GNU tools. For pages that didn't exist, I added stub pages that can be individually filled in by followup patches.

Tested by running `ninja docs-llvm-html` and inspecting locally.

Reviewers: jhenderson, MaskRay, grimar, alexshap

Reviewed By: jhenderson, MaskRay, grimar

Subscribers: smeenai, arphaman, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D63014

llvm-svn: 363100
2019-06-11 21:13:01 +00:00
James Henderson 5058ae0945 [docs][llvm-nm] Add darwin as --format option
llvm-svn: 363081
2019-06-11 15:58:10 +00:00
Sander de Smalen 9d51fa5508 Fix docs build issue introduced by r363035
Replacing '.. code-block:: llvm' by '::' is a quick fix to the
build warning/error: Could not lex literal_block as "llvm".

llvm-svn: 363079
2019-06-11 15:28:13 +00:00
James Henderson 224410b7c1 [docs][llvm-nm] Make --help help text consistent with other options
llvm-svn: 363073
2019-06-11 14:55:31 +00:00
James Henderson 9487963244 [llvm-dwarfdump] Simplify --ignore-case help text and documentation
There was a typo in the --ignore-case help text that was copied into the
llvm-dwarfdump command-guide. Additionally, this patch simplifies the
wording, since it was unnecessarily verbose: the switch applies for
searching in general and doesn't need explicitly stating different
search modes (which might go out-of-date as options are added or
removed).

Reviwed by: JDevlieghere

Differential Revision: https://reviews.llvm.org/D63133

llvm-svn: 363066
2019-06-11 13:51:18 +00:00
James Henderson be7f5c7158 [docs][llvm-nm] Fix documentation regarding llvm-nm reading stdin
llvm-nm reads a.out NOT stdin when no input file is specified. This
patch fixes the doc accordingly, and rephrases the surrounding sentence
slightly.

Reviewed by: grimar

Differential Revision: https://reviews.llvm.org/D63135

llvm-svn: 363065
2019-06-11 13:46:52 +00:00
James Henderson d5f38dae59 [llvm-dwarfdump] Add -o to help text and remove --out-file from doc
-o is in the documentation, but not in the llvm-dwarfdump help text.
This patch adds it by inverting the -o and --out-file aliasing. It also
removes --out-file from the documentation, since we don't really want
people to be using this switch in practice.

Reviewed by: aprantl, JDevlieghere, dblaikie

Differential Revision: https://reviews.llvm.org/D63013

llvm-svn: 363044
2019-06-11 10:20:07 +00:00
Sander de Smalen cbeb563cfb Change semantics of fadd/fmul vector reductions.
This patch changes how LLVM handles the accumulator/start value
in the reduction, by never ignoring it regardless of the presence of
fast-math flags on callsites. This change introduces the following
new intrinsics to replace the existing ones:

  llvm.experimental.vector.reduce.fadd -> llvm.experimental.vector.reduce.v2.fadd
  llvm.experimental.vector.reduce.fmul -> llvm.experimental.vector.reduce.v2.fmul

and adds functionality to auto-upgrade existing LLVM IR and bitcode.

Reviewers: RKSimon, greened, dmgreen, nikic, simoll, aemerson

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D60261

llvm-svn: 363035
2019-06-11 08:22:10 +00:00
Matt Davis 41bf444e61 [Docs] [llvm-mca] Point out a caveat for using llvm-mca markers in source code.
Summary: See: https://bugs.llvm.org/show_bug.cgi?id=42173

Reviewers: andreadb, mattd, RKSimon, spatel

Reviewed By: andreadb

Subscribers: tschuett, gbedwell, llvm-commits, andreadb

Tags: #llvm

Patch by Max Marrone (maxpm)! Thanks!

Differential Revision: https://reviews.llvm.org/D63040

llvm-svn: 362979
2019-06-10 20:38:56 +00:00
Jordan Rupprecht 13d16b94c6 [docs] Add 'git llvm revert' to getting started guide
Summary: This documents `git llvm revert rNNNNNN` in the getting started guide for broader visibility.

Reviewers: jyknight, mehdi_amini

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D63023

llvm-svn: 362966
2019-06-10 17:00:49 +00:00
Nico Weber 80fee25776 Revert r361953 "[SVE][IR] Scalable Vector IR Type"
This reverts commit f4fc01f8dd.
It caused a 3-4x slowdown when doing thinlto links, PR42210.

llvm-svn: 362913
2019-06-09 19:27:50 +00:00
Alexander Shaposhnikov 85ea2de4b5 [llvm-lipo] Add docs for llvm-lipo
Add docs (llvm-lipo.rst) for llvm-lipo.

Test plan:
make -j8 sphinx 
check that ./docs/html/CommandGuide/llvm-lipo.html is built correctly and looks okay.

Differential revision: https://reviews.llvm.org/D62706

llvm-svn: 362848
2019-06-07 22:03:02 +00:00
James Henderson aa8753bc98 [docs]Move llvm-readobj from "Developer Tools" to "Basic Commands"
On the Command Guide page, there are multiple sections with links to the
different documentation pages available for LLVM tools. The "Basic
Tools" section includes tools like llvm-objdump, llvm-nm and so on. The
"Developer Tools" section contains things like FileCheck and lit. This
change moves llvm-readobj into the former block, from the latter.

Reviewed by: MaskRay

Differential Revision: https://reviews.llvm.org/D63011

llvm-svn: 362813
2019-06-07 16:43:44 +00:00
David Tenty b82ea52b78 [NFC] Test commit, whitespace change
As per the Developer Policy, upon obtaining commit access.

llvm-svn: 362753
2019-06-06 22:07:14 +00:00
Thomas Preud'homme 71d3f227a7 FileCheck [6/12]: Introduce numeric variable definition
Summary:
This patch is part of a patch series to add support for FileCheck
numeric expressions. This specific patch introduces support for defining
numeric variable in a CHECK directive.

This commit introduces support for defining numeric variable from a
litteral value in the input text. Numeric expressions can then use the
variable provided it is on a later line.

Copyright:
    - Linaro (changes up to diff 183612 of revision D55940)
    - GraphCore (changes in later versions of revision D55940 and
                 in new revision created off D55940)

Reviewers: jhenderson, chandlerc, jdenny, probinson, grimar, arichardson, rnk

Subscribers: hiraditya, llvm-commits, probinson, dblaikie, grimar, arichardson, tra, rnk, kristina, hfinkel, rogfer01, JonChesterfield

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60386

llvm-svn: 362705
2019-06-06 13:21:06 +00:00
Matt Arsenault 4fb580c314 AMDGPU: Remove amdgpu-max-work-group-size attribute
This has been deprecated for a long time, and mesa recently switched
to amdgpu-flat-work-group-size.

llvm-svn: 362641
2019-06-05 20:32:32 +00:00
Tim Northover b7141207a4 Reapply: IR: add optional type to 'byval' function parameters
When we switch to opaque pointer types we will need some way to describe
how many bytes a 'byval' parameter should occupy on the stack. This adds
a (for now) optional extra type parameter.

If present, the type must match the pointee type of the argument.

The original commit did not remap byval types when linking modules, which broke
LTO. This version fixes that.

Note to front-end maintainers: if this causes test failures, it's probably
because the "byval" attribute is printed after attributes without any parameter
after this change.

llvm-svn: 362128
2019-05-30 18:48:23 +00:00
J. Ryan Stinnett d45eaf9405 [Docs] Modernize references to macOS
Summary:
This updates all places in documentation that refer to "Mac OS X", "OS X", etc.
to instead use the modern name "macOS" when no specific version number is
mentioned.

If a specific version is mentioned, this attempts to use the OS name at the time
of that version:

* Mac OS X for 10.0 - 10.7
* OS X for 10.8 - 10.11
* macOS for 10.12 - present

Reviewers: JDevlieghere

Subscribers: mgorny, christof, arphaman, cfe-commits, lldb-commits, libcxx-commits, llvm-commits

Tags: #clang, #lldb, #libc, #llvm

Differential Revision: https://reviews.llvm.org/D62654

llvm-svn: 362113
2019-05-30 16:46:22 +00:00
Simon Pilgrim 3475a46ec2 Fix sphinx warning about missing footnote.
llvm-svn: 362077
2019-05-30 09:40:35 +00:00
Tim Northover 71ee3d0237 Revert "IR: add optional type to 'byval' function parameters"
The IRLinker doesn't delve into the new byval attribute when mapping types, and
this breaks LTO.

llvm-svn: 362029
2019-05-29 20:46:38 +00:00
Tim Northover 6e07f16fae IR: add optional type to 'byval' function parameters
When we switch to opaque pointer types we will need some way to describe
how many bytes a 'byval' parameter should occupy on the stack. This adds
a (for now) optional extra type parameter.

If present, the type must match the pointee type of the argument.

Note to front-end maintainers: if this causes test failures, it's probably
because the "byval" attribute is printed after attributes without any parameter
after this change.

llvm-svn: 362012
2019-05-29 19:12:48 +00:00
Graham Hunter f4fc01f8dd [SVE][IR] Scalable Vector IR Type
* Adds a 'scalable' flag to VectorType
* Adds an 'ElementCount' class to VectorType to pass (possibly scalable) vector lengths, with overloaded operators.
* Modifies existing helper functions to use ElementCount
* Adds support for serializing/deserializing to/from both textual and bitcode IR formats
* Extends the verifier to reject global variables of scalable types
* Updates documentation

See the latest version of the RFC here: http://lists.llvm.org/pipermail/llvm-dev/2018-July/124396.html

Reviewers: rengolin, lattner, echristo, chandlerc, hfinkel, rkruppe, samparker, SjoerdMeijer, greened, sebpop

Reviewed By: hfinkel, sebpop

Differential Revision: https://reviews.llvm.org/D32530

llvm-svn: 361953
2019-05-29 12:22:54 +00:00
Peter Collingbourne 31fda09b2d Add IR support, ELF section and user documentation for partitioning feature.
The partitioning feature was proposed here:
http://lists.llvm.org/pipermail/llvm-dev/2019-February/130583.html

This is mostly just documentation. The feature itself will be contributed
in subsequent patches.

Differential Revision: https://reviews.llvm.org/D60242

llvm-svn: 361923
2019-05-29 03:29:01 +00:00
Adhemerval Zanella 6d7bf5e8df [CodeGen] Add lrint/llrint builtins
This patch add the ISD::LRINT and ISD::LLRINT along with new
intrinsics.  The changes are straightforward as for other
floating-point rounding functions, with just some adjustments
required to handle the return value being an interger.

The idea is to optimize lrint/llrint generation for AArch64
in a subsequent patch.  Current semantic is just route it to libm
symbol.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D62017

llvm-svn: 361875
2019-05-28 20:47:44 +00:00
Reid Kleckner 414da9d66a Clarify how musttail can be used to create forwarding thunks
llvm-svn: 361590
2019-05-24 01:45:47 +00:00
Thomas Preud'homme 1a944d27b2 FileCheck: Improve FileCheck variable terminology
Summary:
Terminology introduced by [[#]] blocks is confusing and does not
integrate well with existing terminology.

First, variables referred by [[]] blocks are called "pattern variables"
while the text a CHECK directive needs to match is called a "CHECK
pattern". This is inconsistent with variables in [[#]] blocks since
[[#]] blocks are also found in CHECK pattern yet those variables are
called "numeric variable".

Second, the replacing of both [[]] and [[#]] blocks by the value of the
variable or expression they contain is represented by a
FileCheckPatternSubstitution class. The naming refers to being a
substitution in a CHECK pattern but could be wrongly understood as being
a substitution of a pattern variable.

Third and lastly, comments use "numeric expression" to refer both to the
[[#]] blocks as well as to the numeric expressions these blocks contain
which get evaluated at match time.

This patch solves these confusions by
- calling variables in [[]] and [[#]] blocks as string and numeric
  variables respectively;
- referring to [[]] and [[#]] as substitution *blocks*, with the former
  being a string substitution block and the latter a numeric
  substitution block;
- calling [[]] and [[#]] blocks to be replaced by the value of a
  variable or expression they contain a substitution (as opposed to
  definition when these blocks are used to defined a variable), with the
  former being a string substitution and the latter a numeric
  substitution;
- renaming the FileCheckPatternSubstitution as a FileCheckSubstitution
  class with FileCheckStringSubstitution and
  FileCheckNumericSubstitution subclasses;
- restricting the use of "numeric expression" to refer to the expression
  that is evaluated in a numeric substitution.

While numeric substitution blocks only support numeric substitutions of
numeric expressions at the moment there are plans to augment numeric
substitution blocks to support numeric definitions as well as both a
numeric definition and numeric substitution in the same numeric
substitution block.

Reviewers: jhenderson, jdenny, probinson, arichardson

Subscribers: hiraditya, arichardson, probinson, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D62146

llvm-svn: 361445
2019-05-23 00:10:14 +00:00
Lang Hames 00be4e68ad [docs] Make a note of the HowToUseLLJIT example in the ORCv2 design doc.
llvm-svn: 361437
2019-05-22 21:44:46 +00:00
Sanjay Patel 5a4f7cf2ff [IR] allow fast-math-flags on select of FP values
This is a minimal start to correcting a problem most directly discussed in PR38086:
https://bugs.llvm.org/show_bug.cgi?id=38086

We have been hacking around a limitation for FP select patterns by using the
fast-math-flags on the condition of the select rather than the select itself.
This patch just allows FMF to appear with the 'select' opcode. No changes are
needed to "FPMathOperator" because it already includes select-of-FP because
that definition is based on the (return) value type.

Once we have this ability, we can start correcting and adding IR transforms
to use the FMF on a 'select' instruction. The instcombine and vectorizer test
diffs only show that the IRBuilder change is behaving as expected by applying
an FMF guard value to 'select'.

For reference:
rL241901 - allowed FMF with fcmp
rL255555 - allowed FMF with FP calls

Differential Revision: https://reviews.llvm.org/D61917

llvm-svn: 361401
2019-05-22 15:50:46 +00:00
Don Hinton 120a6f09bb [Docs] Increase Doxygen cache size
Summary:
When building Doxygen docs for llvm and clang, it helpfully prints a warning at
the end noting that the `LOOKUP_CACHE_SIZE` value was too small to keep all
symbols in memory.

By increasing to the size it recommends, Doxygen builds have greatly improved
performance. On my machine, time to run `doxygen-llvm` changes from 34 minutes
to 22 minutes, which is a decent amount of time saved by changing a single
number.

Reviewed By: hintonda

Patch by J. Ryan Stinnett!

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D62138

llvm-svn: 361343
2019-05-22 00:56:42 +00:00
Sanjay Patel 587d4b0620 [Docs] fix formatting for bullet list; NFC
llvm-svn: 361341
2019-05-22 00:48:47 +00:00
Sanjay Patel 6a554188aa [InstCombine] fold shuffles of insert_subvectors
This should be a valid exception to the general rule of not creating new shuffle masks in IR...
because we already do it. :)
Also, DAG combining/legalization will undo this by widening the shuffle back out if needed.

Explanation for how we already do this: SLP or vector source can create chains of insert/extract
as shown in 1 of the examples from PR16739:
https://godbolt.org/z/NlK7rA
https://bugs.llvm.org/show_bug.cgi?id=16739

And we expect instcombine or DAGCombine to clean that up by creating relatively simple shuffles.

Differential Revision: https://reviews.llvm.org/D62024

llvm-svn: 361338
2019-05-22 00:32:25 +00:00
Leonard Chan 9bb96980aa Fix for sphinx bot warning
llvm-svn: 361292
2019-05-21 19:30:25 +00:00
Leonard Chan 0bada7ce6c [Intrinsic] Signed Fixed Point Saturation Multiplication Intrinsic
Add an intrinsic that takes 2 signed integers with the scale of them provided
as the third argument and performs fixed point multiplication on them. The
result is saturated and clamped between the largest and smallest representable
values of the first 2 operands.

This is a part of implementing fixed point arithmetic in clang where some of
the more complex operations will be implemented as intrinsics.

Differential Revision: https://reviews.llvm.org/D55720

llvm-svn: 361289
2019-05-21 19:17:19 +00:00
Chris Bieneman da60a16bc7 [docs] Add new document on building distributions
Summary:
This document is an attempt to provide a guide for best practices for using the LLVM build system to generate distributable LLVM-based tools.

Most of the document is geared toward distributions of LLVM-based toolchains, but much of it also applies to distributing other LLVM-based tools and libraries.

Reviewers: tstellar, phosek, jroelofs, hans, sylvestre.ledru

Reviewed By: tstellar

Subscribers: smeenai, dschuff, arphaman, winksaville, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D62040

llvm-svn: 361272
2019-05-21 16:29:31 +00:00