Commit Graph

8270 Commits

Author SHA1 Message Date
Dmitry Preobrazhensky 1c9d681092 [AMDGPU][CODEGEN] Added support of new inline assembler constraints
Added support for constraints 'I', 'J', 'B', 'C', 'DA', 'DB'.

See https://gcc.gnu.org/onlinedocs/gcc/Machine-Constraints.html#Machine-Constraints.

Reviewers: arsenm, rampitec

Differential Revision: https://reviews.llvm.org/D81651
2020-07-02 17:20:15 +03:00
Tony 31fdcf64d2 [AMDGPU] Update DWARF proposal
- Add reference to implicit conversion description.
2020-07-01 20:35:15 +00:00
Tony 76b2d9cbeb [AMDGPU] Correct AMDGPUUsage.rst DW_AT_LLVM_lane_pc example
- Correct typo of DW_OP_xaddr to DW_OP_addrx in AMDGPUUsage.rst for
  DW_AT_LLVM_lane_pc example.

Change-Id: I1b0ee2b24362a0240388e4c2f044c1d4883509b9
2020-07-01 08:23:15 +00:00
Arthur Eubanks f9348f70c2 [Docs][BasicAA] Rename some more basicaa -> basic-aa
Follow up to https://reviews.llvm.org/D82607.
2020-06-30 17:03:45 -07:00
Arthur Eubanks 8b6f675f44 Fix wrong title underline length 2020-06-30 16:02:45 -07:00
Arthur Eubanks 3dfe1440ae [Docs][BasicAA] Rename -basicaa to -basic-aa in docs
Follow up to https://reviews.llvm.org/D82607.
2020-06-30 15:54:28 -07:00
Eric Christopher 8164f69e4c Update the phabricator docs to reflect the monorepo change.
Patch by Nathan Froyd!

Differential Revision: https://reviews.llvm.org/D82389
2020-06-30 10:53:38 -07:00
Jonas Devlieghere 29ea1b4baa [Sphinx] Support older recommonmark versions.
The "new way" of enabling recommonmark is only supported in recommonmark
0.5 and later. Use the deprecated approach with versions of Sphinx that
still support it.

If I understand correctly there's no way to use older versions of
recommonmark (<0.5) with newer versions of Sphinx (>3.0) because the old
approach got removed.

Differential revision: https://reviews.llvm.org/D75284
2020-06-29 09:48:34 -07:00
Mike Edwards 8cd117c24f [LIT] Correcting max-failures option in lit documentation. 2020-06-27 14:57:04 -07:00
Gui Andrade 9aa9855a9c [Docs] BitCodeFormat.rst: List missing attribute codes 2020-06-27 06:34:36 +00:00
Matt Arsenault b091c9a3e1 LLParser: Accept align(N) as new syntax for parameter attribute
Every other value parameter attribute uses parentheses, so accept this
as the preferred modern syntax. Updating everything to use the new
syntax is left for a future change.
2020-06-26 18:10:21 -04:00
Tony 990f8702c9 [AMDGPU] Define DWARF encoding for condition code registers
Summary:
- Define DWARF register numbers for vector and scalar condition codes.
- Document intended purpose of reserved DWARF register numbers.

Reviewers: yaxunl, kzhuravl, arsenm, rampitec, b-sumner

Subscribers: jvesely, wdng, nhaehnle, aprantl, dstuttard, tpr, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D82519
2020-06-26 17:53:55 -04:00
Mehdi Amini 4abf024336 Remove references to the 4.0 release as a major breaking (NFC)
This is cleaning up comments (mostly in the bitcode handling) about
removing some backward compatibility aspect in the 4.0 release.
Historically, "4.0" was used during the development of the 3.x
versions as "this future major breaking change version". At the time
the major number was used to indicate the compatibility. When we
reached 3.9 we decided to change the numbering, instead of going to
3.10 we went to 4.0 but after changing the meaning of the major
number to not mean anything anymore with respect to bitcode backward
compatibility.

The current policy
(https://llvm.org/docs/DeveloperPolicy.html#ir-backwards-compatibility)
indicates only now:

  The current LLVM version supports loading any bitcode since version 3.0.

Differential Revision: https://reviews.llvm.org/D82514
2020-06-25 23:49:07 +00:00
Djordje Todorovic 95435117ad [docs][llvm-dwarfdump] Fix the warnings during docs-llvm-html buil
Before the fix the build of docs-llvm-html would fail.
The D80959 introduced options that are not recognized, so we have
warning as:

  llvm-project/llvm/docs/CommandGuide/llvm-dwarfdump.rst:40\
  :unknown option: --debug-info

Differential Revision: https://reviews.llvm.org/D82460
2020-06-25 11:04:28 +02:00
Djordje Todorovic 019d7a32fe [docs][GlobalISel] Fix the warnings during docs-llvm-html build
Before the fix the build of docs-llvm-html would fail.
The rG8bc03d216824 introduced a reference to an undefined label,
so we have warning as:

  llvm-project/llvm/docs/GlobalISel/GenericOpcode.rst:295:\
  undefined label: i_intr_llvm_ptrmask (if the link has no\
  caption the label must precede a section header)
2020-06-25 10:53:39 +02:00
Mehdi Amini a61c73dbe3 Add a git hook script that can be manually setup to run some checks on every push
Right now it just catches arcanist noisy tags, and include a script to
automatically clean these.

Follow up on http://lists.llvm.org/pipermail/llvm-dev/2019-December/137848.html

Differential Revision: https://reviews.llvm.org/D80978
2020-06-24 21:13:43 +00:00
Vedant Kumar d65cdb498f [docs] Fix typo 2020-06-24 11:51:21 -07:00
Tony ea6df2fb8f [AMDGPU] Update AMD GPU processor information
Summary:
- Add product names for some processors.
- Correct XNACK support for a processor.

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

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D82348
2020-06-23 18:47:56 -04:00
Peter Collingbourne bd7defeb94 llvm-nm: Implement --special-syms.
Differential Revision: https://reviews.llvm.org/D82251
2020-06-22 13:05:47 -07:00
Zhi Zhuang 37fb860301 Add support of __builtin_expect_with_probability
Add a new builtin-function __builtin_expect_with_probability and
intrinsic llvm.expect.with.probability.
The interface is __builtin_expect_with_probability(long expr, long
expected, double probability).
It is mainly the same as __builtin_expect besides one more argument
indicating the probability of expression equal to expected value. The
probability should be a constant floating-point expression and be in
range [0.0, 1.0] inclusive.
It is similar to builtin-expect-with-probability function in GCC
built-in functions.

Differential Revision: https://reviews.llvm.org/D79830
2020-06-22 10:21:28 -07:00
Nikita Popov 93a0f0e4fe [LangRef] Fix sphinx warnings 2020-06-21 13:51:07 +02:00
Nikita Popov f26b420194 [Docs] Fix code block in MemorySSA docs (NFC) 2020-06-21 13:47:00 +02:00
Eric Christopher 8116d01905 Typos around a -> an. 2020-06-20 14:04:48 -07:00
Eric Christopher ae2fa770e1 [docs/examples] As part of using inclusive language within the llvm
project, migrate away from the use of blacklist and whitelist.
2020-06-20 00:51:18 -07:00
Matt Arsenault ae5adb8da5 AMDGPU: Update private null pointer value in documentation
Private pointers used to workaround IR semantics by artifically
reserving an object at offset 0 so no user object would be allocated
there. Since alloca now uses a non-0 address space, that workaround is
unnecssary and 0 can be treated as a valid pointer.
2020-06-18 17:27:19 -04:00
Vedant Kumar b4459b597a [docs] Specify rules for updating debug locations
Summary:
Restructure HowToUpdateDebugInfo.rst to specify rules for when
transformations should preserve, merge, or drop debug locations.

The goal is to have clear, well-justified rules that come with a few
examples and counter-examples, so that pass authors can pick the best
strategy for managing debug locations depending on the specific task at
hand.

I've tried to set down sensible rules here that mostly align with what
we already do in llvm today, and that take a diverse set of use cases
into account (interactive debugging, crash triage, SamplePGO).

Please *do* try to pick these rules apart and suggest clarifications or
improvements :).

Side note: Prior to 24660ea1, this document was structured as a long
list of very specific code transformations -- the idea being that we
would fill in what to do in each specific case. I chose to reorganize
the document as a list of actions to take because it drastically cuts
down on the amount of redundant exposition/explanation needed. I hope
that's fine...

Reviewers: jmorse, aprantl, dblaikie

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D81198
2020-06-18 14:05:45 -07:00
Jonas Devlieghere 9989e81679 [Sphinx] Adjust for source_parsers deprecation in Sphinx 3.0
Update the Sphinx configuration for the removal of source_parsers in
Sphinx 3.0. The variable has been deprecated since version 1.8.

> Version 1.8 deprecates and version 3.0 removes the source_parsers
> configuration variable that was used by older recommonmark versions.

https://www.sphinx-doc.org/en/master/usage/markdown.html

Differential revision: https://reviews.llvm.org/D75284
2020-06-18 14:05:11 -07:00
Amara Emerson 84167a8d58 [docs] Clarify semantics of ordered fadd/fmul reductions.
Differential Revision: https://reviews.llvm.org/D82034
2020-06-18 09:10:43 -07:00
Jean-Michel Gorius b2f2adee00
[llvm][docs] Document the LLVM_INSTALL_UTILS CMake option (NFC) 2020-06-18 15:31:13 +02:00
Florian Hahn 6d18c2067e [Matrix] Update load/store intrinsics.
This patch adjust the load/store matrix intrinsics, formerly known as
llvm.matrix.columnwise.load/store, to improve the naming and allow
passing of extra information (volatile).

The patch performs the following changes:
 * Rename columnwise.load/store to column.major.load/store. This is more
   expressive and also more in line with the naming in Clang.
 * Changes the stride arguments from i32 to i64. The stride can be
   larger than i32 and this makes things more uniform with the way
   things are handled in Clang.
 * A new boolean argument is added to indicate whether the load/store
   is volatile. The lowering respects that when emitting vector
   load/store instructions
 * MatrixBuilder is updated to require both Alignment and IsVolatile
   arguments, which are passed through to the generated intrinsic. The
   alignment is set using the `align` attribute.

The changes are grouped together in a single patch, to have a single
commit that breaks the compatibility. We probably should be fine with
updating the intrinsics, as we did not yet officially support them in
the last stable release. If there are any concerns, we can add
auto-upgrade rules for the columnwise intrinsics though.

Reviewers: anemet, Gerolf, hfinkel, andrew.w.kaylor, LuoYuanke, nicolasvasilache, rjmccall, ftynse

Reviewed By: anemet, nicolasvasilache

Differential Revision: https://reviews.llvm.org/D81472
2020-06-18 09:44:52 +01:00
Zequan Wu bbf89644b5 [llvm-readobj] set --elf-cg-profile as alias of --cg-profile
Summary: Rename --elf-cg-profile to --cg-profile and keep --elf-cg-profile as an alias of --cg-profile.

Reviewers: jhenderson, MaskRay, espindola, hans

Reviewed By: jhenderson, MaskRay

Subscribers: emaste, rupprecht, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D81855
2020-06-17 11:24:45 -07:00
Paul Walker 95db1e7fb9 [FileCheck] Implement * and / operators for ExpressionValue.
Subscribers: arichardson, hiraditya, thopre, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D80915
2020-06-17 09:39:17 +00:00
Matt Arsenault 59ce6ffe2d GlobalISel: Add a note to G_BITCAST documentation
This is currently different from the IR rules.
2020-06-16 11:04:46 -04:00
Erich Keane fad9cba8f5 [Docs] Add missing space, requested on c08ea07 2020-06-15 16:20:32 -07:00
Stanislav Mekhanoshin 9ee272f13d [AMDGPU] Add gfx1030 target
Differential Revision: https://reviews.llvm.org/D81886
2020-06-15 16:18:05 -07:00
Dan Gohman 6604295959 [WebAssembly] WebAssembly doesn't support "protected" visibility
Implement the `hasProtectedVisibility()` hook to indicate that, like
Darwin, WebAssembly doesn't support "protected" visibility.

On ELF, "protected" visibility is intended to be an optimization, however
in practice it often [isn't], and ELF documentation generally ranges from
[not mentioning it at all] to [strongly discouraging its use].

[isn't]: https://www.airs.com/blog/archives/307
[not mentioning it at all]: https://gcc.gnu.org/wiki/Visibility
[strongly discouraging its use]: https://www.akkadia.org/drepper/dsohowto.pdf

While here, also mention the new Reactor support in the release notes.
2020-06-12 19:52:35 -07:00
Erich Keane 884fb45ed2 Update Kaleidoscope tutorial inline code
Reported on IRC, the tutorial code at the bottom of the page correctly
namespaces the FunctionPassManager, but the as-you-go code does not.
This patch adds the namespace to those.
2020-06-12 12:02:35 -07:00
Cyndy Ishida 28fefcc83c [llvm][llvm-nm] add TextAPI/MachO support
Summary:
This completes the needed glueing to support reading tbd files from nm.
This includes specifying which slice filtering with `--arch` and a new
option specifically for tbd files `--add-inlinedinfo` which will show
the reexported libraries that are appended in the tbd file.

Reviewers: ributzka, steven_wu, JDevlieghere, jhenderson

Reviewed By: JDevlieghere

Subscribers: hiraditya, MaskRay, dexonsmith, rupprecht, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D81614
2020-06-11 18:54:16 -07:00
Erich Keane c08ea07716 Add to the Coding Standard our that single-line bodies omit braces
This is a rule that seems to have been enforced for the better part of
the decade, so we should document it for new contributors.

Differential Revision: https://reviews.llvm.org/D80947
2020-06-11 12:46:15 -07:00
Thomas Preud'homme 47934c7cf9 FileCheck [11/12]: Add matching constraint specification
This patch is part of a patch series to add support for FileCheck
numeric expressions. This specific patch adds support for specifying the
matching constraint for a numeric expression, ie. how the value being
matched should relate to the numeric expression.

This commit only adds the equality constraint where the numeric value
matched must be equal to the numeric expression. It is the default
matching constraint used when not specified. It is added to provision
other matching constraint (e.g. inequality relations).

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)

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D60391
2020-06-10 15:56:10 +01:00
Vitaly Buka 4666953ce2 [StackSafety] Add info into function summary
Summary:
This patch adds optional field into function summary,
implements asm and bitcode serialization. YAML
serialization is omitted and can be added later if
needed.

This patch includes this information into summary only
if module contains at least one sanitize_memtag function.
In a near future MTE is the user of the analysis.
Later if needed we can provede more direct control
on when information is included into summary.

Reviewers: eugenis

Subscribers: hiraditya, steven_wu, dexonsmith, arphaman, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D80908
2020-06-10 02:43:28 -07:00
Paul Walker 8fd2270370 [FileCheck] Add function call support to numerical expressions.
This patch extends numerical expressions to allow calls to
predefined functions. These calls can be combined with the
existing numerical operators, which includes nesting calls.

The call syntax is:

  <func>(<args>)

Where <func> is a predefined string literal, currently limited to
one of add, max, min and sub. <arg> is a comma seperated list of
numerical expressions.

Subscribers: arichardson, hiraditya, thopre, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D79936
2020-06-10 09:42:00 +00:00
Mehdi Amini d31c9e5a46 Change filecheck default to dump input on failure
Having the input dumped on failure seems like a better
default: I debugged FileCheck tests for a while without knowing
about this option, which really helps to understand failures.

Remove `-dump-input-on-failure` and the environment variable
FILECHECK_DUMP_INPUT_ON_FAILURE which are now obsolete.

Differential Revision: https://reviews.llvm.org/D81422
2020-06-09 18:57:46 +00:00
Sanjay Patel ad19b9cead [Docs] fix typos for llvm-mca; NFC 2020-06-07 11:14:24 -04:00
Mike Edwards 972a73a347 [LIT] NFC adding max-failures option to lit documentation.
Differential Revision: https://reviews.llvm.org/D81337
2020-06-06 18:26:45 -07:00
madhur13490 bca413b036 Fix a typo in AMDGPU docs
Reviewers: t-tye, arsenm

Reviewed By: arsenm

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

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D81247
2020-06-05 13:30:17 +00:00
Mircea Trofin fa42620afb [docs] Referenced llvm workflow in HowToAddABuilder
Reviewers: gkistanova, dblaikie

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D81046
2020-06-04 16:39:11 -07:00
Vedant Kumar 24660ea11c [docs] HowToUpdateDebugInfo: Minor cleanups
- Change the reference to salvageDebugInfoOrUndef to salvageDebugInfo
  (in accordance with https://reviews.llvm.org/D78369).

- Reorganize a few sections in preparation for an upcoming change that
  attempts to specify rules for updating debug locations.

- Fix some intra-document links.

- Some spelling / wording fixes.
2020-06-04 14:56:01 -07:00
Yuanfang Chen f9ea86eaa1 [Docs] Add the entry for `Advanced builds` in UserGuide.rst
Also add a link to it from ThinLTO.rst.
2020-06-04 14:52:51 -07:00
Jan Korous 5f5d972d83 [docs] Fix self-contradictory description of llvm_unreachable
Just two paragraphs above it says:
"If the compiler does not support this [skipping code generation for a particular branch], it will fall back
to the "abort" implementation."

And that actually correctly describes llvm_unreachable implementation.

Differential Revision: https://reviews.llvm.org/D81130
2020-06-04 11:15:20 -07:00
Yevgeny Rouban dcfa78a4cc Extend InvokeInst !prof branch_weights metadata to unwind branches
Allow InvokeInst to have the second optional prof branch weight for
its unwind branch. InvokeInst is a terminator with two successors.
It might have its unwind branch taken many times. If so
the BranchProbabilityInfo unwind branch heuristic can be inaccurate.
This patch allows a higher accuracy calculated with both branch
weights set.

Changes:
 - A new section about InvokeInst is added to
   the BranchWeightMetadata page. It states the old information that
   missed in the doc and adds new about the second branch weight.
 - Verifier is changed to allow either 1 or 2 branch weights
   for InvokeInst.
 - A new test is written for BranchProbabilityInfo to demonstrate
   the main improvement of the simple fix in calcMetadataWeights().
 - Several new testcases are created for Inliner. Those check that
    both weights are accounted for invoke instruction weight
    calculation.
 - PGOUseFunc::setBranchWeights() is fixed to be applicable to
   InvokeInst.

Reviewers: davidxl, reames, xur, yamauchi
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D80618
2020-06-04 15:37:15 +07:00
Philip Reames 0e7c77053f Introduce a "gc-live" bundle for the gc arguments of a statepoint
Currently, gc.relocates are defined in terms of indices into the statepoint's operand list. Given the gc args are at the end of a variable length list of operands, this makes interpreting their indices by hand a tad challenging. We can simplify the statepoint sequence and improve readability quite a bit by pulling these new operands into their own named operand bundle.

This patch defines a new operand bundle tag "gc-live". The semantics of the bundle are the same as the existing gc arguments of a statepoint. This patch simply introduces the definition and codegen for the bundle, future patches will migrate RS4GC to emitting the new form.

Interestingly, with this done and the recent migration to using deopt and gc-transition bundles, we really don't have much left in the statepoint itself. It really looks like the existing ID and flags fields are redundant; we have (existing!) attributes for all of them. I think we'll be able to reduce the gc.statepoint signature to simply a wrapped call (e.g. actual target and actual arguments).

Differential Revision: https://reviews.llvm.org/D80937
2020-06-03 15:00:24 -07:00
Braedy Kuzma 90e291912a [LangRef] Fix description of shape args for matrix.multiply.
Currently all code instances within the matrix lowering pass consider
matrix A to be MxN and B to be NxK, producing C which is MxK. Anyone
interacting with this API after reading the docs but without reading the pass
would expect A: MxK, B: KxN, and C: MxN. These changes bring the documentation
in line with the implementation.

One point of concern with this, the original signature as described in the docs
may be better or at least more expected. The interface as it was written
reflected other common matrix multiplication interfaces such as BLAS'[1], where
the matrices are MxK, KxN, MxN respectively. Choosing to honor this requires
changing code and tests instead, but should be mostly just renaming of variables.

Patch by Braedy Kuzma <braedy@ualberta.ca>

[1] http://www.netlib.org/lapack/explore-html/db/dc9/group__single__blas__level3_gafe51bacb54592ff5de056acabd83c260.html#gafe51bacb54592ff5de056acabd83c260

Reviewers: anemet, LuoYuanke, nicolasvasilache, fhahn

Reviewed By: fhahn

Differential Revision: https://reviews.llvm.org/D80663
2020-06-03 11:25:44 +01:00
Nick Desaulniers 8eda71616f [Clang][A32/T32][Linux] -O1 implies -fomit-frame-pointer
Summary:
An upgrade of LLVM for CrOS [0] containing [1] triggered a bunch of
errors related to writing to reserved registers for a Linux kernel's
arm64 compat vdso (which is a aarch32 image).

After a discussion on LKML [2], it was determined that
-f{no-}omit-frame-pointer was not being specified. Comparing GCC and
Clang [3], it becomes apparent that GCC defaults to omitting the frame
pointer implicitly when optimizations are enabled, and Clang does not.
ie. setting -O1 (or above) implies -fomit-frame-pointer. Clang was
defaulting to -fno-omit-frame-pointer implicitly unless -fomit-frame-pointer
was set explicitly.

Why this becomes a problem is that the Linux kernel's arm64 compat vdso
contains code that uses r7. r7 is used sometimes for the frame pointer
(for example, when targeting thumb (-mthumb)). See useR7AsFramePointer()
in llvm/llvm-project/llvm/lib/Target/ARM/ARMSubtarget.h. This is mostly
for legacy/compatibility reasons, and the 2019 Q4 revision of the ARM
AAPCS looks to standardize r11 as the frame pointer for aarch32, though
this is not yet implemented in LLVM.

Users that are reliant on the implicit value if unspecified when
optimizations are enabled should explicitly choose -fomit-frame-pointer
(new behavior) or -fno-omit-frame-pointer (old behavior).

[0] https://bugs.chromium.org/p/chromium/issues/detail?id=1084372
[1] https://reviews.llvm.org/D76848
[2] https://lore.kernel.org/lkml/20200526173117.155339-1-ndesaulniers@google.com/
[3] https://godbolt.org/z/0oY39t

Reviewers: kristof.beyls, psmith, danalbert, srhines, MaskRay, ostannard, efriedma

Reviewed By: psmith, danalbert, srhines, MaskRay, efriedma

Subscribers: efriedma, olista01, MaskRay, vhscampos, cfe-commits, llvm-commits, manojgupta, llozano, glider, hctim, eugenis, pcc, peter.smith, srhines

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D80828
2020-06-02 15:54:14 -07:00
Diego Caballero b78b98491a Update 'git push' command in GettingStarted guide
'git push' command, without any other arguments, can do different
things depending on the local configuration of Git. This patch
updates the 'git push' command with extra arguments to be more
resilient to any local configuration.

Reviewed By: mehdi_amini

Differential Revision: https://reviews.llvm.org/D79964
2020-06-02 21:25:29 +03:00
Jonas Devlieghere 5b460fb15e [llvm-dwarfdump] Print [=<offset>] after --debug-* options in help output.
Some of the --debug-* options can take an optional offset. Although the
man page does a good job of making that clear, it's much harder to
discover from the help output.

Currently the only reference to this is the following sentence:

> Where applicable these parameters take an optional =<offset> argument
> to dump only the entry at the specified offset.

This patch changes the help output from to print [=<offset>] after the
options that take an offset.

  --debug-info[=<offset>]    - Dump the .debug_info section

rdar://problem/63150066

Differential revision: https://reviews.llvm.org/D80959
2020-06-02 11:06:11 -07:00
Vedant Kumar b429a0fef0 [docs] Sketch outline for HowToUpdateDebugInfo.rst
Summary:
Sketch the outline for a new document that explains how to update debug
info in various kinds of code transformations.

Some of the guidelines that belong in HowToUpdateDebugInfo.rst were in
SourceLevelDebugging.rst already under the debugify section. It seems
like the distinction between the two docs ought to be that the former is
more prescriptive, while the latter is more descriptive.

To that end I've consolidated the "how to update debug info" guidelines
which were in SourceLevelDebugging.rst into the new doc, along with the
information about using "debugify" to test transformations. Since we've
added a mir-debugify pass, I've described that as well.

Reviewers: aprantl, jmorse, chrisjackson, dsanders

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D80052
2020-06-01 16:45:18 -07:00
Tony 7318e24000 [AMDGPU] Add loaded code object path URI definition to AMDGPUUsage
Differential Revision: https://reviews.llvm.org/D80407
2020-05-29 19:52:52 -04:00
Sjoerd Meijer 7fb8a40e52 New intrinsic @llvm.get.active.lane.mask()
This is split off from D79100 and:
- adds a intrinsic description/definition for @llvm.get.active.lane.mask(), and
- describe its semantics in LangRef.

As described (in more detail) in its LangRef section, it is semantically
equivalent to an icmp with the vector induction variable and the back-edge
taken count, and generates a mask of active/inactive vector lanes.

It will have several use cases. First, it will be used by the
ExpandVectorPredication pass for the VP intrinsics, to expand VP intrinsics for
scalable vectors on targets that do not support the `%evl` parameter, see
D78203.

Also, this is part of, and essential for our ARM MVE tail-predication story:
- this intrinsic will be emitted by the LoopVectorizer in D79100, when
  the scalar epilogue is tail-folded into the vector body. This new intrinsic
  will generate the predicate for the masked loads/stores, and it takes the
  back-edge taken count as an argument. The back-edge taken count represents the
  number of elements processed by the loop, which we need to setup MVE
  tail-predication.
- Emitting the intrinsic is controlled by a new TTI hook, see D80597.
- We pick up this new intrinsic in an ARM MVETailPredication backend pass, see
  D79175, and convert it to a MVE target specific intrinsic/instruction to
  create a tail-predicated loop.

Differential Revision: https://reviews.llvm.org/D80596
2020-05-29 08:51:40 +01:00
Tony b4668a268d [AMDGPU] DWARF Proposal For Heterogeneous Debugging
- Add introduction to DWARF Proposal For Heterogeneous Debugging.

Differential Revision: https://reviews.llvm.org/D70523
2020-05-28 20:36:21 -04:00
Thomas Preud'homme 23ac16cf9b FileCheck [10/12]: Add support for signed numeric values
Summary:
This patch is part of a patch series to add support for FileCheck
numeric expressions. This specific patch adds support signed numeric
values, thus allowing negative numeric values.

As such, the patch adds a new class to represent a signed or unsigned
value and add the logic for type promotion and type conversion in
numeric expression mixing signed and unsigned values. It also adds
the %d format specifier to represent signed value.

Finally, it also adds underflow and overflow detection when performing a
binary operation.

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

Reviewed By: jhenderson, arichardson

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

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60390
2020-05-28 10:44:21 +01:00
Sjoerd Meijer 880c35a554 [HardwareLoops] LangRef Intrinsic descriptions
The HardwareLoop intrinsics were missing and not described in LangRef. This
adds these descriptions/definitions.

Differential Revision: https://reviews.llvm.org/D80316
2020-05-28 08:36:04 +01:00
Sourabh Singh Tomar c1d5b831b1 [docs] Release notes for DIModule metadata
Updated the release notes for the changes in the DIModule metadata.

Reviewed By: aprantl

Differential Revision: https://reviews.llvm.org/D80614
2020-05-28 10:17:40 +05:30
Alex Richardson 3be5e53f20 [FileCheck] Allow parenthesized expressions
With this change it is be possible to write FileCheck expressions such
as [[#(VAR+1)-2]]. Currently, the only supported arithmetic operators are
plus and minus, so this is not particularly useful yet. However, it our
CHERI fork we have tests that benefit from having multiplication in
FileCheck expressions. Allowing parenthesized expressions is the simplest
way for us to work around the current lack of operator precedence in
FileCheck expressions.

Reviewed By: thopre, jhenderson
Differential Revision: https://reviews.llvm.org/D77383
2020-05-27 16:31:39 +01:00
Matt Arsenault 8e3307f551 GlobalISel: Add a clarification to G_STORE documentation
Mirror the note on G_LOAD. We probably do need to add an explicit
G_TRUNCSTORE opcode for the vector case, although I do not have a use
for it.
2020-05-26 21:20:30 -04:00
Alexander Shaposhnikov 842a8cc10c [llvm-objcopy][MachO] Add support for removing Swift symbols
cctools strip has the option "-T" which removes Swift symbols.
This diff implements this option in llvm-strip for MachO.

Test plan: make check-all

Differential revision: https://reviews.llvm.org/D80099
2020-05-26 16:49:56 -07:00
Arthur Eubanks 9a0b0855a9 Modify verifier checks to support musttail + preallocated
Summary:
preallocated and musttail can work together, but we don't want to call
@llvm.call.preallocated.setup() to modify the stack in musttail calls.
So we shouldn't have the "preallocated" operand bundle when a
preallocated call is musttail.

Also disallow use of preallocated on calls without preallocated.

Codegen not yet implemented.

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D80581
2020-05-26 15:20:20 -07:00
Vedant Kumar 6e39379bbb [DwarfExpression] Support entry values for indirect parameters
Summary:
A struct argument can be passed-by-value to a callee via a pointer to a
temporary stack copy. Add support for emitting an entry value DBG_VALUE
when an indirect parameter DBG_VALUE becomes unavailable. This is done
by omitting DW_OP_stack_value from the entry value expression, to make
the expression describe the location of an object.

rdar://63373691

Reviewers: djtodoro, aprantl, dstenb

Subscribers: hiraditya, lldb-commits, llvm-commits

Tags: #lldb, #llvm

Differential Revision: https://reviews.llvm.org/D80345
2020-05-26 14:22:28 -07:00
Stefanos Baziotis ef94f60ff7 [MSSA][Doc] Fix typo 2020-05-26 22:16:13 +03:00
Stefanos Baziotis 2c7d63257d [MSSA][Doc] Clobbers, more info on Defs / Def chain
- Added more info about what we refer as a clobber in MSSA.
- Added more info about MemoryDefs and how there is a single Def chain.
- The doc portrayed MSSA as modeling the heap whileit is modeling
  the whole memory, so I changed the wording to not be heap-specific.

Differential Revision: https://reviews.llvm.org/D80000
2020-05-26 20:43:17 +03:00
Matt Arsenault 8bc03d2168 GlobalISel: Merge G_PTR_MASK with llvm.ptrmask intrinsic
Confusingly, these were unrelated and had different semantics. The
G_PTR_MASK instruction predates the llvm.ptrmask intrinsic, but has a
different format. G_PTR_MASK only allows clearing the low bits of a
pointer, and only a constant number of bits. The ptrmask intrinsic
allows an arbitrary mask. Replace G_PTR_MASK to match the intrinsic.

Only selects the cases that look like the old instruction. More work
is needed to select the general case. Also new legalization code is
still needed to deal with the case where the incoming mask size does
not match the pointer size, which has a specified behavior in the
langref.
2020-05-26 11:48:13 -04:00
Serge Pavlov 4d20e31f73 [FPEnv] Intrinsic llvm.roundeven
This intrinsic implements IEEE-754 operation roundToIntegralTiesToEven,
and performs rounding to the nearest integer value, rounding halfway
cases to even. The intrinsic represents the missed case of IEEE-754
rounding operations and now llvm provides full support of the rounding
operations defined by the standard.

Differential Revision: https://reviews.llvm.org/D75670
2020-05-26 19:24:58 +07:00
Nico Weber 5229dd1366 [build] Add LLVM_LOCAL_RPATH which can set an rpath on just unit test binaries
After D80096, bots that build clang for distribution and that can't use
system gcc / libstdc++ need to pass a working rpath so that unit test
binaries can run. The method suggested in GettingStarted.rst works fine
for local development, but it results in an absolute local rpath ending
up even in distributed binaries like clang, which is both ugly and
unnecessary.

Add an explicit toggle that can be used to add an rpath only for the
non-distributed binaries that need it.

Differential Revision: https://reviews.llvm.org/D80534
2020-05-26 06:23:57 -04:00
Serge Pavlov 61f72dd8ac [FPEnv] Small fixes to implementation of flt.rounds
This change makes minor correction to the implementation of intrinsic
`llvm.flt.rounds`:
- Added documentation entry in LangRef,
- Attributes of the intrinsic changed to be in line with other functions
  dependent of floating-point environment.

Differential Revision: https://reviews.llvm.org/D79322
2020-05-26 13:19:01 +07:00
Dmitry Preobrazhensky b087b91c91 [AMDGPU][CODEGEN] Added 'A' constraint for inline assembler
Summary: 'A' constraint requires an immediate int or fp constant that can be inlined in an instruction encoding.

Reviewers: arsenm, rampitec

Differential Revision: https://reviews.llvm.org/D78494
2020-05-25 14:23:34 +03:00
Michal Paszkowski 335de55fa3 Revert "Added a new IRCanonicalizer pass."
This reverts commit 14d358537f.
2020-05-23 13:51:43 +02:00
Michal Paszkowski 14d358537f Added a new IRCanonicalizer pass.
Summary:
Added a new IRCanonicalizer pass which aims to transform LLVM modules into
a canonical form by reordering and renaming instructions while preserving the
same semantics. The canonicalizer makes it easier to spot semantic differences
when diffing two modules which have undergone different passes.

Presentation: https://www.youtube.com/watch?v=c9WMijSOEUg

Reviewed by: plotfi

Differential Revision: https://reviews.llvm.org/D66029
2020-05-23 12:45:53 +02:00
Tony 8a9f09df42 [AMDGPU] DWARF Proposal For Heterogeneous Debugging
- Change title to "DWARF Proposal For Heterogeneous Debugging".
2020-05-22 22:29:57 -04:00
Tony 1b58cbad01 [AMDGPU] DWARF For Heterogeneous Debugging
- Change title to "DWARF For Heterogeneous Debugging".
- Add "Examples" section that references the AMDGPUUsage DWARF section.
- Make the "References" section a top level section.

Differential Revision: https://reviews.llvm.org/D70523
2020-05-22 22:14:20 -04:00
Jinsong Ji 9b7fba1421 [docs][llvm-extract] Add missing alias/bb options
llvm-extract get serveral new options, but we forgot to update doc.
This patch update the doc.

Reviewed By: volkan

Differential Revision: https://reviews.llvm.org/D80413
2020-05-22 03:52:07 +00:00
Tony e36be90c82 [AMDGPU] Correct formatting typos in documentation
Summary:
- Correct missing space in some "note" and "TODO" directives in
  AMDGPUUsage.rst
- Correct warning for heading underline being too short in
  BitCodeFormat.rst

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

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D80407
2020-05-21 20:36:46 -04:00
Jinsong Ji 628f008b20 [docs] Fix buildbot failures
Buildbot has been failing since
http://lab.llvm.org:8011/builders/llvm-sphinx-docs/builds/44711

This patch fix the minor issues that cause warnings.
2020-05-21 22:07:33 +00:00
Jonas Devlieghere 92fd3971e0 [dsymutil] Add reproducers to dsymutil
Add support for generating a dsymutil reproducer. The result is a folder
containing all the object files for linking.

When --gen-reproducer is passed, dsymutil uses a FileCollectorFileSystem
which keeps track of all the files used by dsymutil. These files are
copied into a temporary directory when dsymutil exists.

When this path is passed to --use-reproducer, dsymutil uses a
RedirectingFileSystem that will use the files from the reproducer
directory instead of the actual paths. This means you don't need to mess
with the OSO path prefix.

Differential revision: https://reviews.llvm.org/D79398
2020-05-21 10:59:49 -07:00
Eli Friedman f26bdb539e Make Value::getPointerAlignment() return an Align, not a MaybeAlign.
If we don't know anything about the alignment of a pointer, Align(1) is
still correct: all pointers are at least 1-byte aligned.

Included in this patch is a bugfix for an issue discovered during this
cleanup: pointers with "dereferenceable" attributes/metadata were
assumed to be aligned according to the type of the pointer.  This
wasn't intentional, as far as I can tell, so Loads.cpp was fixed to
stop making this assumption. Frontends may need to be updated.  I
updated clang's handling of C++ references, and added a release note for
this.

Differential Revision: https://reviews.llvm.org/D80072
2020-05-20 16:37:20 -07:00
Zola Bridges b2d733c350 [llvm][docs] Add step by step git to GettingStarted
Summary:
Due to deleting the git llvm script, folks were asking for better documentation
about how to use git in order to commit to the Github repo. I added some step
by step git commands to make the usage clearer.

Context link: http://lists.llvm.org/pipermail/llvm-dev/2020-May/141640.html

Reviewed By: spatel, mehdi_amini

Differential Revision: https://reviews.llvm.org/D80088
2020-05-19 12:14:17 -07:00
Jonas Devlieghere b7924d6525 [dsymutil] Make sure the --help output and man page are consistent
As suggested by Adrian in D79398.
2020-05-18 11:38:36 -07:00
Christudasan Devadasan 7c4e711ef8 [AMDGPU] Enable base pointer.
When the callee requires a dynamic stack realignment,
it is not possible to correcty access the incoming
stack arguments using the stack pointer. We reserve a
base pointer in such cases to access the function arguments
inside the callee. The base pointer will hold the incoming
stack pointer value before any kind of delta added to it.

Reviewed By: arsenm, scott.linder

Differential Revision: https://reviews.llvm.org/D78811
2020-05-17 16:13:55 +05:30
Nikita Popov f89f7da999 [IR] Convert null-pointer-is-valid into an enum attribute
The "null-pointer-is-valid" attribute needs to be checked by many
pointer-related combines. To make the check more efficient, convert
it from a string into an enum attribute.

In the future, this attribute may be replaced with data layout
properties.

Differential Revision: https://reviews.llvm.org/D78862
2020-05-15 19:41:07 +02:00
Ties Stuij 8c24f33158 [IR][BFloat] Add BFloat IR type
Summary:
The BFloat IR type is introduced to provide support for, initially, the BFloat16
datatype introduced with the Armv8.6 architecture (optional from Armv8.2
onwards). It has an 8-bit exponent and a 7-bit mantissa and behaves like an IEEE
754 floating point IR type.

This is part of a patch series upstreaming Armv8.6 features. Subsequent patches
will upstream intrinsics support and C-lang support for BFloat.

Reviewers: SjoerdMeijer, rjmccall, rsmith, liutianle, RKSimon, craig.topper, jfb, LukeGeeson, sdesmalen, deadalnix, ctetreau

Subscribers: hiraditya, llvm-commits, danielkiss, arphaman, kristof.beyls, dexonsmith

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D78190
2020-05-15 14:43:43 +01:00
Alok Kumar Sharma 4042ada1c1 [DebugInfo] support for DW_AT_data_location in llvm
This patch adds support for DWARF attribute DW_AT_data_location.

Summary:
Dynamic arrays in fortran are described by array descriptor and
data allocation address. Former is mapped to DW_AT_location and
later is mapped to DW_AT_data_location.

Testing:
unit test cases added (hand-written)
check llvm
check debug-info

Reviewed By: aprantl

Differential Revision: https://reviews.llvm.org/D79592
2020-05-15 11:33:17 +05:30
Alok Kumar Sharma ab699d78a2 [DebugInfo] llvm rejects DWARF operator DW_OP_push_object_address
llvm rejects DWARF operator DW_OP_push_object_address.This DWARF
operator is needed for Flang to support allocatable array.

Summary:
Currently llvm rejects DWARF operator DW_OP_push_object_address.
below error is produced when llvm finds this operator.

[..]
invalid expression
!DIExpression(151)
warning: ignoring invalid debug info in pushobj.ll
[..]

There are some parts missing in support of this operator, need to
be completed.

Testing
-added a unit testcase
-check-debuginfo
-check-llvm

Reviewed By: aprantl

Differential Revision: https://reviews.llvm.org/D79306
2020-05-15 11:10:35 +05:30
Wei Mi 67bb16049a [llvm-profdata] Update CommandGuide
Add a bunch of SampleFDO related flags added recently into llvm-profdata to
its command guide.

Differential Revision: https://reviews.llvm.org/D79911
2020-05-14 13:59:42 -07:00
Mircea Trofin ee33ee68fe [docs] Add link to zorg github project
Reviewers: gkistanova

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D79891
2020-05-13 13:41:16 -07:00
Joel E. Denny a1fd188223 [FileCheck] Support comment directives
Sometimes you want to disable a FileCheck directive without removing
it entirely, or you want to write comments that mention a directive by
name.  The `COM:` directive makes it easy to do this.  For example,
you might have:

```
; X32: pinsrd_1:
; X32:    pinsrd $1, 4(%esp), %xmm0

; COM: FIXME: X64 isn't working correctly yet for this part of codegen, but
; COM: X64 will have something similar to X32:
; COM:
; COM:   X64: pinsrd_1:
; COM:   X64:    pinsrd $1, %edi, %xmm0
```

Without this patch, you need to use some combination of rewording and
directive syntax mangling to prevent FileCheck from recognizing the
commented occurrences of `X32:` and `X64:` above as directives.
Moreover, FileCheck diagnostics have been proposed that might complain
about the occurrences of `X64` that don't have the trailing `:`
because they look like directive typos:

  <http://lists.llvm.org/pipermail/llvm-dev/2020-April/140610.html>

I think dodging all these problems can prove tedious for test authors,
and directive syntax mangling already makes the purpose of existing
test code unclear.  `COM:` can avoid all these problems.

This patch also updates the small set of existing tests that define
`COM` as a check prefix:

- clang/test/CodeGen/default-address-space.c
- clang/test/CodeGenOpenCL/addr-space-struct-arg.cl
- clang/test/Driver/hip-device-libs.hip
- llvm/test/Assembler/drop-debug-info-nonzero-alloca.ll

I think lit should support `COM:` as well.  Perhaps `clang -verify`
should too.

Reviewed By: jhenderson, thopre

Differential Revision: https://reviews.llvm.org/D79276
2020-05-13 11:29:48 -04:00
Zequan Wu cb22ab7403 Add nomerge function attribute to supress tail merge optimization in simplifyCFG
We want to add a way to avoid merging identical calls so as to keep the
separate debug-information for those calls. There is also an asan
usecase where having this attribute would be beneficial to avoid
alternative work-arounds.

Here is the link to the feature request:
https://bugs.llvm.org/show_bug.cgi?id=42783.

`nomerge` is different from `noline`. `noinline` prevents function from
inlining at callsites, but `nomerge` prevents multiple identical calls
from being merged into one.

This patch adds `nomerge` to disable the optimization in IR level. A
followup patch will be needed to let backend understands `nomerge` and
avoid tail merge at backend.

Reviewed By: asbirlea, rnk

Differential Revision: https://reviews.llvm.org/D78659
2020-05-12 16:49:20 -07:00
Michael Kruse 5c707fd97c [docs] Corrected inaccuracies in Common Problems section.
Changed the language in LLVM_USE_LINKER to more strongly recommend LLD
and to specify that the GNU gold linker is only useful if LLD is
unavailable in binary form and it is the first build of LLVM. Added that
LLD will help when used on ELF-based platforms.

Corrected information in CMAKE_BUILD_TYPE regarding the Release build
type and enabling assertions.

Added option LLVM_ENABLE_ASSERTIONS and mentioned enabling this option
with a Release build as an alternative to using a Debug build.

Specified that the LLVM_OPTIMIZED_TABLEGEN
option is only for Debug builds, that the LLVM_USE_SPLIT_DWARF option
is only available on ELF host platforms, and that setting
CLANG_ENABLE_STATIC_ANALYZER to OFF only slightly improves build time.

These changes address comments made in D75425.

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D77346
2020-05-12 10:09:37 -05:00
Joel E. Denny d0e7fd6b62 Revert "[FileCheck] Support comment directives"
This reverts commit 9a9a5f9893 to try to
fix a bot:

http://lab.llvm.org:8011/builders/llvm-clang-x86_64-expensive-checks-win/builds/23489
2020-05-11 19:41:22 -04:00
Joel E. Denny 9a9a5f9893 [FileCheck] Support comment directives
Sometimes you want to disable a FileCheck directive without removing
it entirely, or you want to write comments that mention a directive by
name.  The `COM:` directive makes it easy to do this.  For example,
you might have:

```
; X32: pinsrd_1:
; X32:    pinsrd $1, 4(%esp), %xmm0

; COM: FIXME: X64 isn't working correctly yet for this part of codegen, but
; COM: X64 will have something similar to X32:
; COM:
; COM:   X64: pinsrd_1:
; COM:   X64:    pinsrd $1, %edi, %xmm0
```

Without this patch, you need to use some combination of rewording and
directive syntax mangling to prevent FileCheck from recognizing the
commented occurrences of `X32:` and `X64:` above as directives.
Moreover, FileCheck diagnostics have been proposed that might complain
about the occurrences of `X64` that don't have the trailing `:`
because they look like directive typos:

  <http://lists.llvm.org/pipermail/llvm-dev/2020-April/140610.html>

I think dodging all these problems can prove tedious for test authors,
and directive syntax mangling already makes the purpose of existing
test code unclear.  `COM:` can avoid all these problems.

This patch also updates the small set of existing tests that define
`COM` as a check prefix:

- clang/test/CodeGen/default-address-space.c
- clang/test/CodeGenOpenCL/addr-space-struct-arg.cl
- clang/test/Driver/hip-device-libs.hip
- llvm/test/Assembler/drop-debug-info-nonzero-alloca.ll

I think lit should support `COM:` as well.  Perhaps `clang -verify`
should too.

Reviewed By: jhenderson, thopre

Differential Revision: https://reviews.llvm.org/D79276
2020-05-11 14:53:48 -04:00
Matthias Schiffer a2247d42e4 [LangRef] Describe linkage types, allocation size of declarations for global variables
Linkage type was only referenced for functions, not for global
variables.

Clarify that LLVM doesn't make assumption about the allocation size when
no definitive initializer for a global variable is known.

Differential Revision: https://reviews.llvm.org/D78952
2020-05-08 16:21:30 -07:00
Jonas Devlieghere 7fb9bcd3da [dsymutil] Add option to print statistics about the .debug_info size.
This patch adds statistics about the contribution of each object file to
the linked debug info. When --statistics is passed to dsymutil, it
prints a table after linking as illustrated below.

It lists the object file name, the size of the debug info in the object
file in bytes, and the absolute size contribution to the linked dSYM and
the percentage difference. The table is sorted by the output size, so
the object files contributing the most to the link are listed first.

.debug_info section size (in bytes)
-------------------------------------------------------------------------------
Filename                                           Object         dSYM   Change
-------------------------------------------------------------------------------
basic2.macho.x86_64.o                                210b         165b  -24.00%
basic3.macho.x86_64.o                                177b         150b  -16.51%
basic1.macho.x86_64.o                                125b         129b    3.15%
-------------------------------------------------------------------------------
Total                                                512b         444b  -14.23%
-------------------------------------------------------------------------------

Differential revision: https://reviews.llvm.org/D79513
2020-05-06 19:48:45 -07:00
Stanislav Mekhanoshin b856ff9782 [AMDGPU] Added 'a' constraint documentation. NFC.
AGPR inline asm constraint was missing from the LangRef.rst.
2020-05-05 13:52:04 -07:00
Sanjay Patel a954b8a363 [ValueTracking] fix CannotBeNegativeZero() to disregard 'nsz' FMF
The 'nsz' flag is different than 'nnan' or 'ninf' in that it does not create poison.
Make that explicit in the LangRef and fix ValueTracking analysis that misinterpreted
the definition.

This manifests as bugs in InstSimplify shown in the test diffs and as discussed in
PR45778:
https://bugs.llvm.org/show_bug.cgi?id=45778

Differential Revision: https://reviews.llvm.org/D79422
2020-05-05 16:04:59 -04:00
Christudasan Devadasan 375cec4b6c [AMDGPU] Introduce more scratch registers in the ABI.
The AMDGPU target has a convention that defined all VGPRs
(execept the initial 32 argument registers) as callee-saved.
This convention is not efficient always, esp. when the callee
requiring more registers, ended up emitting a large number of
spills, even though its caller requires only a few.

This patch revises the ABI by introducing more scratch registers
that a callee can freely use.
The 256 vgpr registers now become:
  32 argument registers
  112 scratch registers and
  112 callee saved registers.
The scratch registers and the CSRs are intermixed at regular
intervals (a split boundary of 8) to obtain a better occupancy.

Reviewers: arsenm, t-tye, rampitec, b-sumner, mjbedy, tpr

Reviewed By: arsenm, t-tye

Differential Revision: https://reviews.llvm.org/D76356
2020-05-05 23:02:58 +05:30
James Henderson 5beb9fa4ab [docs][llvm-objcopy] Update --output-target text with right defaults
The --output-target documentation has slightly rotted, as the default is
no longer purely based on the input file format, but also the value of
--input-target. This patch updates the documentation to make this
explicit.

Reviewed by: MaskRay, alexshap

Differential Revision: https://reviews.llvm.org/D79318
2020-05-05 11:22:56 +01:00
Djordje Todorovic 0a4defe8c8 [llvm-dwarfdump][Stats] Clean up
This addresses:
  -Clean up the source code
  -Refactor the JSON fields
  -Fix the test cases
  -Improve the docs for the stats output

Differential Revision: https://reviews.llvm.org/D77789
2020-05-04 09:35:40 +02:00
Thomas Preud'homme 0b85ea8533 [docs][FileCheck] Fix invalid example
Summary:
FileCheck documentation contains an example of a numeric variable
defined and used on the same line. This is not currently supported by
FileCheck so this commit fixes the example to use CHECK-SAME for the
variable use.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D79253
2020-05-02 23:31:18 +01:00
James Henderson 91257fdb21 [docs][llvm-cxxfilt] Document --no-strip-underscore option
This option was added several months ago in commit e84468c1.

Reviewed by: MaskRay, erik.pilkington, steven_wu

Differential Revision: https://reviews.llvm.org/D79166
2020-05-01 11:03:06 +01:00
Scott Linder 084f3cf92b [AMDGPU] Update DWARF proposal encodings
Update the tentative encodings to avoid a conflict with a GNU extension.

Differential Revision: https://reviews.llvm.org/D70523
2020-04-30 14:02:54 -04:00
James Henderson 027eb25121 [docs][llvm-cxxfilt] Fix indentation in rst file
This makes it consistent throughout the options, although the end result
is unchanged.
2020-04-30 10:41:45 +01:00
Tony 756ba3548c [AMDGPU] DWARF proposal review feedback
- Rename DW_OP_LLVM_offset_constu to DW_OP_LLVM_offset_uconst to
  matches DW_OP_plus_uconst.
- Correct DW_OP_LLVM_call_ref to be DW_OP_call_ref.
- Move proposed changes to a separate section to clarify that the
  introduction section is not part of the changes.
- Fix formatting typos and add missing reference.
- Clarify why DW_OP_LLVM_offset et al do not wrap on overflow.
- Correct syntax of augmentation string.

Differential Revision: https://reviews.llvm.org/D70523
2020-04-28 00:56:25 -04:00
Arthur Eubanks 3b0450acec Add IR constructs for preallocated (inalloca replacement)
Add llvm.call.preallocated.{setup,arg} instrinsics.
Add "preallocated" operand bundle which takes a token produced by llvm.call.preallocated.setup.
Add "preallocated" parameter attribute, which is like byval but without the copy.

Verifier changes for these IR constructs.

See https://github.com/rnk/llvm-project/blob/call-setup-docs/llvm/docs/CallSetup.md

Subscribers: hiraditya, jdoerfert, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D74651
2020-04-27 16:15:50 -07:00
Sergei Trofimovich 41eb0fc00d [Lexicon] fix typo "may is" -> "is"
Reviewers: MaskRay

Reviewed By: MaskRay

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D78878
2020-04-26 19:35:25 +01:00
Jon Roelofs 42bf0756d4 [docs] Fix :option: links 2020-04-25 16:19:02 -06:00
James Y Knight fb8152dcfe [CallSite removal] Remove the text describing CallSite from the manual. 2020-04-23 22:17:19 -04:00
James Y Knight 248a5db3f2 Change callbr to only define its output SSA variable on the normal
path, not the indirect targets.

Fixes: PR45565.

Differential Revision: https://reviews.llvm.org/D78341
2020-04-23 19:36:44 -04:00
Xing GUO 12224162a1 [dsymutil][doc] Improve documentation.
This change helps improve `dsymutil` documentation.

- Add missing options
- Re-arrange options in alphabetical order
- Wrap inline options in double-back-quote
- `-v` is for `--version` not `--verbose`

Reviewed By: JDevlieghere

Differential Revision: https://reviews.llvm.org/D78479
2020-04-23 20:06:52 +08:00
Kazuaki Ishizaki 0312b9f550 [llvm] NFC: Fix trivial typo in rst and td files
Differential Revision: https://reviews.llvm.org/D77469
2020-04-23 14:26:32 +09:00
Jon Roelofs dc5c1fa882 [docs] Fix :option: links 2020-04-22 14:00:30 -06:00
Jon Roelofs b3f168274d [docs] Document lit's --timeout=N flag 2020-04-22 12:57:25 -06:00
Mikhail Maltsev 089fbe6919 [Docs] Fixed formatting in release notes, NFC 2020-04-22 18:25:22 +01:00
Mikhail Maltsev d7ab9e7c9b [ARM] Release notes for the Custom Datapath Extension (CDE)
Summary:
This change mentions CDE assembly in the LLVM release notes and CDE
intrinsics in both Clang and LLVM release notes.

Reviewers: kristof.beyls, simon_tatham

Reviewed By: kristof.beyls

Subscribers: danielkiss, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D78481
2020-04-22 16:34:19 +01:00
Zola Bridges 0f12480bd1 [dfsan] Add "DataFlow" option to LLVM_USE_SANITIZER
Summary:
This patch add the dataflow option to LLVM_USE_SANITIZER and documents
it.

Tested via check-cxx (wip to fix the errors).

Reviewers: morehouse, #libc!

Subscribers: mgorny, cfe-commits, libcxx-commits

Tags: #clang, #libc

Differential Revision: https://reviews.llvm.org/D78390
2020-04-20 10:30:52 -07:00
Tyker ff9379f4b2 [NFC] Remove waymarking because it improves performances
Summary:
This patch remove waymarking and replaces it with storing a pointer to the User in the Use.
here are the results on the measurements for the CTMark tests of the test suite.
```
Metric: instructions_count

Program                                                      baseline      patched       diff
 test-suite :: CTMark/ClamAV/clamscan.test                    72557942065   71733653521  -1.1%
 test-suite :: CTMark/sqlite3/sqlite3.test                    76281422939   75484840636  -1.0%
 test-suite :: CTMark/consumer-typeset/consumer-typeset.test  51364676366   50862185614  -1.0%
 test-suite :: CTMark/SPASS/SPASS.test                        60476106505   59908437767  -0.9%
 test-suite :: CTMark/tramp3d-v4/tramp3d-v4.test              112578442329  111725050856 -0.8%
 test-suite :: CTMark/mafft/pairlocalalign.test               50846133013   50473644539  -0.7%
 test-suite :: CTMark/kimwitu++/kc.test                       54692641250   54349070299  -0.6%
 test-suite :: CTMark/7zip/7zip-benchmark.test                182216614747  181216091230 -0.5%
 test-suite :: CTMark/Bullet/bullet.test                      123459210616  122905866767 -0.4%
 Geomean difference                                                                      -0.8%

Metric: peak_memory_use

Program                                                      baseline  patched   diff
 test-suite :: CTMark/tramp3d-v4/tramp3d-v4.test              326864    338524    3.6%
 test-suite :: CTMark/sqlite3/sqlite3.test                    216412    221240    2.2%
 test-suite :: CTMark/7zip/7zip-benchmark.test                11808284  12022604  1.8%
 test-suite :: CTMark/Bullet/bullet.test                      6831752   6945988   1.7%
 test-suite :: CTMark/SPASS/SPASS.test                        2682552   2721820   1.5%
 test-suite :: CTMark/ClamAV/clamscan.test                    5037256   5107936   1.4%
 test-suite :: CTMark/consumer-typeset/consumer-typeset.test  2752728   2790768   1.4%
 test-suite :: CTMark/mafft/pairlocalalign.test               1517676   1537244   1.3%
 test-suite :: CTMark/kimwitu++/kc.test                       1090748   1103448   1.2%
 Geomean difference                                                               1.8%

Metric: compile_time

Program                                                      baseline patched diff
 test-suite :: CTMark/consumer-typeset/consumer-typeset.test  14.71    14.38  -2.2%
 test-suite :: CTMark/sqlite3/sqlite3.test                    23.18    22.73  -2.0%
 test-suite :: CTMark/7zip/7zip-benchmark.test                57.96    56.99  -1.7%
 test-suite :: CTMark/ClamAV/clamscan.test                    20.75    20.49  -1.2%
 test-suite :: CTMark/kimwitu++/kc.test                       18.35    18.15  -1.1%
 test-suite :: CTMark/SPASS/SPASS.test                        18.72    18.57  -0.8%
 test-suite :: CTMark/mafft/pairlocalalign.test               14.09    14.00  -0.6%
 test-suite :: CTMark/Bullet/bullet.test                      37.38    37.19  -0.5%
 test-suite :: CTMark/tramp3d-v4/tramp3d-v4.test              33.81    33.76  -0.2%
 Geomean difference                                                           -1.1%
```

i believe that it is worth trading +1.8% peak memory use for -1.1% compile time.
also this patch removes waymarking which simplifies the Use and User classes.

Reviewers: nikic, lattner

Reviewed By: lattner

Subscribers: russell.gallop, foad, ggreif, rriddle, ekatz, fhahn, lebedev.ri, mgorny, hiraditya, george.burgess.iv, asbirlea, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D77144
2020-04-17 11:27:10 +02:00
Richard Smith 9a709dd2bb llvm-addr2line: assume addresses on the command line are hexadecimal rather than attempting to guess the base based on the form of the number.
Summary:
This matches the behavior of GNU addr2line. We previously treated
hexadecimal addresses as binary if they started with 0b, otherwise as
octal if they started with 0, otherwise as decimal.

This only affects llvm-addr2line; the behavior of llvm-symbolize is
unaffected.

Reviewers: ikudrin, rupprecht, jhenderson

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73306
2020-04-16 16:16:21 -07:00
Lang Hames a9ade27a57 [docs] Fix an RST error introduced in e823068306.
This should fix the 'Explicit markup ends without a blank line' error seen on
http://lab.llvm.org:8011/builders/llvm-sphinx-docs.

Thanks to Daniel Sanders for spotting this.
2020-04-15 14:37:58 -07:00
Tony 1eac2c55d8 [AMDGPU] Move DWARF proposal to separate file
- Move DWARF proposal for heterogeneous debugging to a separate file.
- Add references.

Differential Revision: https://reviews.llvm.org/D70523
2020-04-15 17:19:39 -04:00
Craig Topper 8dfb9627b7 [X86] Make v32i16/v64i8 legal types without avx512bw. Use custom splitting instead.
This moves v32i16/v64i8 to a model consistent with how we
treat integer types with avx1.

This does change the ABI for types vXi16/vXi8 vectors larger than
512 bits to pass in multiple zmms instead of multiple ymms. We'd
already hacked some code to make v64i8/v32i16 pass in zmm.

Cost model is still a bit of a mess. In some place I tried to
match existing behavior. But really we need to account for
splitting and concating costs. Cost model for shuffles is
especially pessimistic.

Differential Revision: https://reviews.llvm.org/D76212
2020-04-15 12:17:18 -07:00
Tony b436124010 [AMDGPU] Update DWARF proposal
- Unify the sections on DWARF expression and location lists.

- Allow a location description to have one or more single location
  descriptions.

- Define context of DWARF expression that includes an initial
  stack. Allow initial stack to be used when evaluating location list
  expression with overlapping PC ranges.

- Reorganize the DWARF proposal in AMDGPUUsage so suitable for
  submission to the DWARF site.

- Replace CFI instruction DW_CFA_LLVM_def_cfa_aspace with
  DW_CFA_def_aspace_cfa and DW_CFA_def_aspace_cfa_sf. This is to avoid
  the problem that DW_CFA_def_cfa and DW_CFA_def_cfa_sf cannot use a
  register that is not the size of an address in the CFA address
  space.

- Clarify DWARF address class and DWARF address space. Define language
  values for DWARF address classes and specify how they are used by
  some common source languages.

- Define rules for accessing registers and derefencing memory when the
  type size and register size or byte size operand do not match.

- Numerous cleanups for consistency.

Differential Revision: https://reviews.llvm.org/D70523
2020-04-14 20:05:15 -04:00
Lang Hames 840a23b0b5 [ORC] Update ORCv2 docs to reflect removal of ExecutionSession::getMainJITDylib.
Thanks to Dibyendu Majumdar for spotting the issue.
2020-04-13 12:52:44 -07:00
Lang Hames e823068306 [Support] Add support RTTI support for open class hierarchies.
This patch extracts the RTTI part of llvm::ErrorInfo into its own class
(RTTIExtends) so that it can be used in other non-error hierarchies, and makes
it compatible with the existing LLVM RTTI function templates (isa, cast,
dyn_cast, dyn_cast_or_null) by adding the classof method.

Differential Revision: https://reviews.llvm.org/D39111
2020-04-13 12:52:44 -07:00
Benjamin Kramer ebd5290ff2 Address sphinx warnings
LanguageExtensions.rst:2191: WARNING: Title underline too short.
llvm-symbolizer.rst:157: Error in "code-block" directive: maximum 1 argument(s) allowed, 30 supplied.
2020-04-13 14:41:55 +02:00
SCOTT-HAMILTON 4d62c34402 Typos correction. 2020-04-13 13:46:18 +02:00
Nico Weber 0fffece463 fix some doc typos to cycle bots 2020-04-13 06:28:59 -04:00
Stefanos Baziotis 72ffeb2d38 [LoopTerminology] LCSSA: Fix typo in code sample 2020-04-12 04:40:55 +03:00
Djordje Todorovic 3505226702 [docs][llvm-dwarfdump] Add the release notes about --show-section-sizes
Note that the llvm-dwarfdump has the new option.

Differential Revision: https://reviews.llvm.org/D77495
2020-04-10 10:35:18 +02:00
Qiu Chaofan 68460148d5 [Docs] Add more FP option description for llc
This patch adds missing description of enable-no-signed-zeros-fp-math
and enable-no-trapping-fp-math options of llc.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D77713
2020-04-09 17:13:01 +08:00
Serge Pavlov c7ff5b38f2 [FPEnv] Use single enum to represent rounding mode
Now compiler defines 5 sets of constants to represent rounding mode.
These are:

1. `llvm::APFloatBase::roundingMode`. It specifies all 5 rounding modes
defined by IEEE-754 and is used in `APFloat` implementation.

2. `clang::LangOptions::FPRoundingModeKind`. It specifies 4 of 5 IEEE-754
rounding modes and a special value for dynamic rounding mode. It is used
in clang frontend.

3. `llvm::fp::RoundingMode`. Defines the same values as
`clang::LangOptions::FPRoundingModeKind` but in different order. It is
used to specify rounding mode in in IR and functions that operate IR.

4. Rounding mode representation used by `FLT_ROUNDS` (C11, 5.2.4.2.2p7).
Besides constants for rounding mode it also uses a special value to
indicate error. It is convenient to use in intrinsic functions, as it
represents platform-independent representation for rounding mode. In this
role it is used in some pending patches.

5. Values like `FE_DOWNWARD` and other, which specify rounding mode in
library calls `fesetround` and `fegetround`. Often they represent bits
of some control register, so they are target-dependent. The same names
(not values) and a special name `FE_DYNAMIC` are used in
`#pragma STDC FENV_ROUND`.

The first 4 sets of constants are target independent and could have the
same numerical representation. It would simplify conversion between the
representations. Also now `clang::LangOptions::FPRoundingModeKind` and
`llvm::fp::RoundingMode` do not contain the value for IEEE-754 rounding
direction `roundTiesToAway`, although it is supported natively on
some targets.

This change defines all the rounding mode type via one `llvm::RoundingMode`,
which also contains rounding mode for IEEE rounding direction `roundTiesToAway`.

Differential Revision: https://reviews.llvm.org/D77379
2020-04-09 13:26:47 +07:00
Sanjay Patel 5c472420b6 [LangRef] update text for shufflevector
D72467 updated the shufflevector instruction to include a constant mask
rather than a mask operand. The LangRef text was vague enough to still
make sense, but it is better to update here too, so there's no confusion
about valid mask values. The text here is adapted from the documentation
code comments for "class ShuffleVectorInst".

Differential Revision: https://reviews.llvm.org/D77396
2020-04-08 09:01:01 -04:00
Djordje Todorovic 3a4d9f8335 [docs] Add the release notes about Debug Entry Values
Note that x86, arm and aarch64 targets support the Debug Entry Values
feature by default.

Differential Revision: https://reviews.llvm.org/D77494
2020-04-07 12:08:22 +02:00
Louis Dionne 8a42bf24ae [lit] Move the recursiveExpansionLimit setting to TestingConfig
The LitConfig is shared across the whole test suite. However, since
enabling recursive expansion can be a breaking change for some test
suites, it's important to confine the setting to test suites that
enable it explicitly.

Note that other issues were raised with the way recursiveExpansionLimit
operates. However, this commit simply moves the setting to the right
place -- the mechanism by which it works can be improved independently.

Differential Revision: https://reviews.llvm.org/D77415
2020-04-06 13:58:00 -04:00
diggerlin a26a441b99 [llvm-objdump][XCOFF] Use symbol index+symbol name + storage mapping class as label for -D
SUMMARY:

For the llvm-objdump -D, the symbol name is used as a label in the disassembly for the specific address (when a symbol address is equal to the virtual address in the dump).

In XCOFF, multiple symbols may have the same name, being differentiated by their storage mapping class. It is helpful to print the QualName and not just the name when forming the output label for a csect symbol. The symbol index further removes any ambiguity caused by duplicate names.

To maintain compatibility with the binutils objdump, the XCOFF-specific --symbol-description option is added to enable the enhanced format.

Reviewers: hubert.reinterpretcast, James Henderson, Jason Liu ,daltenty
Subscribers: wuzish, nemanjai, hiraditya

Differential Revision: https://reviews.llvm.org/D72973
2020-04-06 10:10:10 -04:00
vgxbj 948ef5b1a6 [llvm-objdump] Teach `llvm-objdump` dump dynamic symbols.
Summary:
This patch is to teach `llvm-objdump` dump dynamic symbols (`-T` and `--dynamic-syms`). Currently, this patch is not fully compatible with `gnu-objdump`, but I would like to continue working on this in next few patches. It has two issues.

1. Some symbols shouldn't be marked as global(g). (`-t/--syms` has same issue as well) (Fixed by D75659)
2. `gnu-objdump` can dump version information and *dynamically* insert before symbol name field.

`objdump -T a.out` gives:

```
DYNAMIC SYMBOL TABLE:
0000000000000000  w   D  *UND*  0000000000000000              _ITM_deregisterTMCloneTable
0000000000000000      DF *UND*  0000000000000000  GLIBC_2.2.5 printf
0000000000000000      DF *UND*  0000000000000000  GLIBC_2.2.5 __libc_start_main
0000000000000000  w   D  *UND*  0000000000000000              __gmon_start__
0000000000000000  w   D  *UND*  0000000000000000              _ITM_registerTMCloneTable
0000000000000000  w   DF *UND*  0000000000000000  GLIBC_2.2.5 __cxa_finalize
```

`llvm-objdump -T a.out` gives:

```
DYNAMIC SYMBOL TABLE:
0000000000000000  w   D  *UND*  0000000000000000 _ITM_deregisterTMCloneTable
0000000000000000 g    DF *UND*  0000000000000000 printf
0000000000000000 g    DF *UND*  0000000000000000 __libc_start_main
0000000000000000  w   D  *UND*  0000000000000000 __gmon_start__
0000000000000000  w   D  *UND*  0000000000000000 _ITM_registerTMCloneTable
0000000000000000  w   DF *UND*  0000000000000000 __cxa_finalize
```

Reviewers: jhenderson, grimar, MaskRay, espindola

Reviewed By: jhenderson, grimar

Subscribers: emaste, rupprecht, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D75756
2020-04-05 10:46:59 +08:00
Mehdi Amini 1ce0bc39ee Add mention of advantages of `arc` in the Phabricator doc.
Differential Revision: https://reviews.llvm.org/D76952
2020-04-04 03:22:29 +00:00
Guillaume Chatelet 9f5c786876 [NFC] G_DYN_STACKALLOC realign iff align > 1, update documentation
Summary: I think it would be better to require the alignment to be >= 1. It is currently confusing to allow both values.

Reviewers: courbet

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D77372
2020-04-03 08:12:39 +00:00
Matt Arsenault 75cf30918f AMDGPU: Assume f32 denormals are enabled by default
This will likely introduce catastrophic performance regressions on
older subtargets, but should be correct. A follow up change will
remove the old fp32-denormals subtarget features, and switch to using
the new denormal-fp-math/denormal-fp-math-f32 attributes. Frontends
should be making sure to add the denormal-fp-math-f32 attribute when
appropriate to avoid performance regressions.
2020-04-02 17:17:12 -04:00
Alexander Lanin 6668453dd2 [docs] use git diff instead of git format-patch
Uploading output from `git format-patch` fails when version has
more than 2 dots, e.g. git version 2.24.1.windows.2 which is
currently recommended by e.g. GitExtensions or 2.24.1.rc on Linux.

Differential Revision: https://reviews.llvm.org/D72374
2020-04-02 07:20:27 -07:00
Stefanos Baziotis 8348e9d71b [LoopTerminology] Make term names bold
Differential Revision: https://reviews.llvm.org/D77151
2020-04-02 14:53:18 +03:00
Djordje Todorovic 5e508b9bac [llvm-dwarfdump] Add the --show-sections-sizes option
Add an option to llvm-dwarfdump to calculate the bytes within
the debug sections. Dump this numbers when using --statistics
option as well.

This is an initial patch (e.g. we should support other units,
since we only support 'bytes' now).

Differential Revision: https://reviews.llvm.org/D74205
2020-04-02 13:14:30 +02:00
Roman Lebedev de22d7154b
[llvm-exegesis] 'Min' repetition mode
Summary:
As noted in documentation, different repetition modes have different trade-offs:

> .. option:: -repetition-mode=[duplicate|loop]
>
>  Specify the repetition mode. `duplicate` will create a large, straight line
>  basic block with `num-repetitions` copies of the snippet. `loop` will wrap
>  the snippet in a loop which will be run `num-repetitions` times. The `loop`
>  mode tends to better hide the effects of the CPU frontend on architectures
>  that cache decoded instructions, but consumes a register for counting
>  iterations.

Indeed. Example:

>>! In D74156#1873657, @lebedev.ri wrote:
> At least for `CMOV`, i'm seeing wildly different results
> |           | Latency | RThroughput |
> | duplicate | 1       | 0.8         |
> | loop      | 2       | 0.6         |
> where latency=1 seems correct, and i'd expect the througput to be close to 1/2 (since there are two execution units).

This isn't great for analysis, at least for schedule model development.

As discussed in excruciating detail in

>>! In D74156#1924514, @gchatelet wrote:
>>>! In D74156#1920632, @lebedev.ri wrote:
>> ... did that explanation of the question i'm having made any sense?
>
> Thx for digging in the conversation !
> Ok it makes more sense now.
>
> I discussed it a bit with @courbet:
>  - We want the analysis tool to stay simple so we'd rather not make it knowledgeable of the repetition mode.
>  - We'd like to still be able to select either repetition mode to dig into special cases
>
> So we could add a third `min` repetition mode that would run both and take the minimum. It could be the default option.
> Would you have some time to look what it would take to add this third mode?

there appears to be an agreement that it is indeed sub-par,
and that we should provide an optional, measurement (not analysis!) -time
way to rectify the situation.

However, the solutions isn't entirely straight-forward.

We can just add an actual 'multiplexer' `MinSnippetRepetitor`, because
if we just concatenate snippets produced by `DuplicateSnippetRepetitor`
and `LoopSnippetRepetitor` and run+measure that, the measurement will
naturally be different from what we'd get by running+measuring
them separately and taking the min.
([[ https://www.wolframalpha.com/input/?i=%28x%2By%29%2F2+%21%3D+min%28x%2C+y%29 | `time(D+L)/2 != min(time(D), time(L))` ]])

Also, it seems best to me to have a single snippet instead of generating
a snippet per repetition mode, since the only difference here is that the
loop repetition mode reserves one register for loop counter.

As far as i can tell, we can either teach `BenchmarkRunner::runConfiguration()`
to produce a single report given multiple repetitors (as in the patch),
or do that one layer higher - don't modify `BenchmarkRunner::runConfiguration()`,
produce multiple reports, don't actually print each one, but aggregate them somehow
and only print the final one.

Initially i've gone ahead with the latter approach, but it didn't look like a natural fit;
the former (as in the diff) does seem like a better fit to me.

There's also a question of the test coverage. It sure currently does work here:
```
$ ./bin/llvm-exegesis --opcode-name=CMOV64rr --mode=inverse_throughput --repetition-mode=duplicate
Check generated assembly with: /usr/bin/objdump -d /tmp/snippet-8fb949.o
---
mode:            inverse_throughput
key:
  instructions:
    - 'CMOV64rr RAX RAX R11 i_0x0'
    - 'CMOV64rr RBP RBP R15 i_0x0'
    - 'CMOV64rr RBX RBX RBX i_0x0'
    - 'CMOV64rr RCX RCX RBX i_0x0'
    - 'CMOV64rr RDI RDI R10 i_0x0'
    - 'CMOV64rr RDX RDX RAX i_0x0'
    - 'CMOV64rr RSI RSI RAX i_0x0'
    - 'CMOV64rr R8 R8 R8 i_0x0'
    - 'CMOV64rr R9 R9 RDX i_0x0'
    - 'CMOV64rr R10 R10 RBX i_0x0'
    - 'CMOV64rr R11 R11 R14 i_0x0'
    - 'CMOV64rr R12 R12 R9 i_0x0'
    - 'CMOV64rr R13 R13 R12 i_0x0'
    - 'CMOV64rr R14 R14 R15 i_0x0'
    - 'CMOV64rr R15 R15 R13 i_0x0'
  config:          ''
  register_initial_values:
    - 'RAX=0x0'
    - 'R11=0x0'
    - 'EFLAGS=0x0'
    - 'RBP=0x0'
    - 'R15=0x0'
    - 'RBX=0x0'
    - 'RCX=0x0'
    - 'RDI=0x0'
    - 'R10=0x0'
    - 'RDX=0x0'
    - 'RSI=0x0'
    - 'R8=0x0'
    - 'R9=0x0'
    - 'R14=0x0'
    - 'R12=0x0'
    - 'R13=0x0'
cpu_name:        bdver2
llvm_triple:     x86_64-unknown-linux-gnu
num_repetitions: 10000
measurements:
  - { key: inverse_throughput, value: 0.819, per_snippet_value: 12.285 }
error:           ''
info:            instruction has tied variables, using static renaming.
assembled_snippet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
...
$ ./bin/llvm-exegesis --opcode-name=CMOV64rr --mode=inverse_throughput --repetition-mode=loop
Check generated assembly with: /usr/bin/objdump -d /tmp/snippet-051eb3.o
---
mode:            inverse_throughput
key:
  instructions:
    - 'CMOV64rr RAX RAX R11 i_0x0'
    - 'CMOV64rr RBP RBP RSI i_0x0'
    - 'CMOV64rr RBX RBX R9 i_0x0'
    - 'CMOV64rr RCX RCX RSI i_0x0'
    - 'CMOV64rr RDI RDI RBP i_0x0'
    - 'CMOV64rr RDX RDX R9 i_0x0'
    - 'CMOV64rr RSI RSI RDI i_0x0'
    - 'CMOV64rr R9 R9 R12 i_0x0'
    - 'CMOV64rr R10 R10 R11 i_0x0'
    - 'CMOV64rr R11 R11 R9 i_0x0'
    - 'CMOV64rr R12 R12 RBP i_0x0'
    - 'CMOV64rr R13 R13 RSI i_0x0'
    - 'CMOV64rr R14 R14 R14 i_0x0'
    - 'CMOV64rr R15 R15 R10 i_0x0'
  config:          ''
  register_initial_values:
    - 'RAX=0x0'
    - 'R11=0x0'
    - 'EFLAGS=0x0'
    - 'RBP=0x0'
    - 'RSI=0x0'
    - 'RBX=0x0'
    - 'R9=0x0'
    - 'RCX=0x0'
    - 'RDI=0x0'
    - 'RDX=0x0'
    - 'R12=0x0'
    - 'R10=0x0'
    - 'R13=0x0'
    - 'R14=0x0'
    - 'R15=0x0'
cpu_name:        bdver2
llvm_triple:     x86_64-unknown-linux-gnu
num_repetitions: 10000
measurements:
  - { key: inverse_throughput, value: 0.6083, per_snippet_value: 8.5162 }
error:           ''
info:            instruction has tied variables, using static renaming.
assembled_snippet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
...
$ ./bin/llvm-exegesis --opcode-name=CMOV64rr --mode=inverse_throughput --repetition-mode=min
Check generated assembly with: /usr/bin/objdump -d /tmp/snippet-c7a47d.o
Check generated assembly with: /usr/bin/objdump -d /tmp/snippet-2581f1.o
---
mode:            inverse_throughput
key:
  instructions:
    - 'CMOV64rr RAX RAX R11 i_0x0'
    - 'CMOV64rr RBP RBP R10 i_0x0'
    - 'CMOV64rr RBX RBX R10 i_0x0'
    - 'CMOV64rr RCX RCX RDX i_0x0'
    - 'CMOV64rr RDI RDI RAX i_0x0'
    - 'CMOV64rr RDX RDX R9 i_0x0'
    - 'CMOV64rr RSI RSI RAX i_0x0'
    - 'CMOV64rr R9 R9 RBX i_0x0'
    - 'CMOV64rr R10 R10 R12 i_0x0'
    - 'CMOV64rr R11 R11 RDI i_0x0'
    - 'CMOV64rr R12 R12 RDI i_0x0'
    - 'CMOV64rr R13 R13 RDI i_0x0'
    - 'CMOV64rr R14 R14 R9 i_0x0'
    - 'CMOV64rr R15 R15 RBP i_0x0'
  config:          ''
  register_initial_values:
    - 'RAX=0x0'
    - 'R11=0x0'
    - 'EFLAGS=0x0'
    - 'RBP=0x0'
    - 'R10=0x0'
    - 'RBX=0x0'
    - 'RCX=0x0'
    - 'RDX=0x0'
    - 'RDI=0x0'
    - 'R9=0x0'
    - 'RSI=0x0'
    - 'R12=0x0'
    - 'R13=0x0'
    - 'R14=0x0'
    - 'R15=0x0'
cpu_name:        bdver2
llvm_triple:     x86_64-unknown-linux-gnu
num_repetitions: 10000
measurements:
  - { key: inverse_throughput, value: 0.6073, per_snippet_value: 8.5022 }
error:           ''
info:            instruction has tied variables, using static renaming.
assembled_snippet: 5541574156415541545348B8000000000000000049BB00000000000000004883EC08C7042400000000C7442404000000009D48BD000000000000000049BA000000000000000048BB000000000000000048B9000000000000000048BA000000000000000048BF000000000000000049B9000000000000000048BE000000000000000049BC000000000000000049BD000000000000000049BE000000000000000049BF0000000000000000490F40C3490F40EA490F40DA480F40CA480F40F8490F40D1480F40F04C0F40CB4D0F40D44C0F40DF4C0F40E74C0F40EF4D0F40F14C0F40FD490F40C3490F40EA5B415C415D415E415F5DC35541574156415541545348B8000000000000000049BB00000000000000004883EC08C7042400000000C7442404000000009D48BD000000000000000049BA000000000000000048BB000000000000000048B9000000000000000048BA000000000000000048BF000000000000000049B9000000000000000048BE000000000000000049BC000000000000000049BD000000000000000049BE000000000000000049BF000000000000000049B80200000000000000490F40C3490F40EA490F40DA480F40CA480F40F8490F40D1480F40F04C0F40CB4D0F40D44C0F40DF4C0F40E74C0F40EF4D0F40F14C0F40FD4983C0FF75C25B415C415D415E415F5DC3
...
```
but i open to suggestions as to how test that.

I also have gone with the suggestion to default to this new mode.
This was irking me for some time, so i'm happy to finally see progress here.
Looking forward to feedback.

Reviewers: courbet, gchatelet

Reviewed By: courbet, gchatelet

Subscribers: mstojanovic, RKSimon, llvm-commits, courbet, gchatelet

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D76921
2020-04-02 09:28:35 +03:00
Serguei Katkov 2ede5dccff [DOC] Remove too strong restriction for ‘llvm.experimental.gc.statepoint’ Intrinsic
The requirement for deopt parameter to be in gc parameter if it can
be modified by GC is very strong and difficult to follow.

The key example of why this can't work:
%p1 = bitcast i8* %p to i8*
statepoint [gc = (%p1)], [deopt = (%p1)]

The optimizer is allowed to replace either use (or both) of %p1 with %p.
If it updates only one of the two (entirely legal), the two sets do not overlap.

So this change removes the strong wording.

Reviewers: reames, dantrushin
Reviewed By: reames
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D77122
2020-04-02 10:56:42 +07:00