Commit Graph

7169 Commits

Author SHA1 Message Date
Fangrui Song edcb29349a [docs] Remove reference to makellvm which was removed in rL329041
llvm-svn: 343165
2018-09-27 03:48:04 +00:00
Clement Courbet 86ecf46fb4 [llvm-exegesis] Fix doc in r342947.
llvm-exegesis.rst was using invalid indentation for bullet points.

llvm-svn: 342948
2018-09-25 07:48:38 +00:00
Clement Courbet 78b2e73d15 [llvm-exegesis] Allow benchmarking arbitrary code snippets.
Summary:

This is a step towards fixing PR38048.

Note that right now the measurements are given per instruction. We'll
need to give measurements a per code snippet and update the analysis (PR38731).

Reviewers: gchatelet

Subscribers: tschuett, llvm-commits

Differential Revision: https://reviews.llvm.org/D52041

llvm-svn: 342947
2018-09-25 07:31:44 +00:00
Kristina Brooks a3421c3ca9 [Docs] [Support] Correct a missed reference and use up to date .inc examples.
In my original diff I missed #include "llvm/System/Thing.h" and forgot to update a
reference to .inc files a few lines down. This patch corrects these things as 
they were missed in revision 342500.

llvm-svn: 342705
2018-09-21 01:53:51 +00:00
Calixte Denizet eb7f60201c [IR] Add a boolean field in DILocation to know if a line must covered or not
Summary:
Some lines have a hit counter where they should not have one.
For example, in C++, some cleanup is adding at the end of a scope represented by a '}'.
So such a line has a hit counter where a user expects to not have one.
The goal of the patch is to add this information in DILocation which is used to get the covered lines in GCOVProfiling.cpp.
A following patch in clang will add this information when generating IR (https://reviews.llvm.org/D49916).

Reviewers: marco-c, davidxl, vsk, javed.absar, rnk

Reviewed By: rnk

Subscribers: eraman, xur, danielcdh, aprantl, rnk, dblaikie, #debug-info, vsk, llvm-commits, sylvestre.ledru

Tags: #debug-info

Differential Revision: https://reviews.llvm.org/D49915

llvm-svn: 342631
2018-09-20 08:53:06 +00:00
Sylvestre Ledru 439c29f5ea Improve the doc about the initial commit email sent to the ML
llvm-svn: 342622
2018-09-20 07:43:24 +00:00
Kristina Brooks 405c1a1272 Remove svn:executable from a documentation file.
Should fix the buildbot failure caused by it.

llvm-svn: 342502
2018-09-18 18:37:16 +00:00
Kristina Brooks ab834fd89c [Docs] [Support] System Library to Support Library transition along with minor corrections to reflect it.
System Library has been a long deprecated term along with the path lib/System, having been superseded/renamed
to the Support Library a long time ago. These patches reflect those changes in documentation as well as
update some outdated examples and provide context to the origin of the Support Library.

Differential Revision: https://reviews.llvm.org/D52107

llvm-svn: 342500
2018-09-18 18:05:38 +00:00
Teresa Johnson ab2a7f0f69 [ThinLTO] Update LangRef doc for summary parsing
Summary:
Remove note about summary being ignored. Update to reflect the
fact that summary is now parsed by llvm-as.

While here, fix one summary format that changed since the initial
implementation.

Reviewers: dexonsmith

Subscribers: inglorion, llvm-commits

Differential Revision: https://reviews.llvm.org/D51540

llvm-svn: 342479
2018-09-18 13:44:13 +00:00
Richard Smith 3164fcfd27 Add flag to llvm-profdata to allow symbols in profile data to be remapped, and
add a tool to generate symbol remapping files.

Summary:
The new tool llvm-cxxmap builds a symbol mapping table from a file containing
a description of partial equivalences to apply to mangled names and files
containing old and new symbol tables.

Reviewers: davidxl

Subscribers: mgorny, llvm-commits

Differential Revision: https://reviews.llvm.org/D51470

llvm-svn: 342168
2018-09-13 20:22:02 +00:00
Hans Wennborg 7c890242cb ReleaseNotes: update links to use https
llvm-svn: 341785
2018-09-10 08:50:31 +00:00
Reid Kleckner 403959e302 [benchmark] Re-enable benchmarks on all platforms including Windows
The assertion in MCCodeView.cpp was resolved in r340878.

This reverts both r340905 and r340836, making benchmarks build by
default everywhere.

llvm-svn: 341716
2018-09-07 21:47:00 +00:00
Chandler Carruth 664aa868f5 [x86/SLH] Add a real Clang flag and LLVM IR attribute for Speculative
Load Hardening.

Wires up the existing pass to work with a proper IR attribute rather
than just a hidden/internal flag. The internal flag continues to work
for now, but I'll likely remove it soon.

Most of the churn here is adding the IR attribute. I talked about this
Kristof Beyls and he seemed at least initially OK with this direction.
The idea of using a full attribute here is that we *do* expect at least
some forms of this for other architectures. There isn't anything
*inherently* x86-specific about this technique, just that we only have
an implementation for x86 at the moment.

While we could potentially expose this as a Clang-level attribute as
well, that seems like a good question to defer for the moment as it
isn't 100% clear whether that or some other programmer interface (or
both?) would be best. We'll defer the programmer interface side of this
for now, but at least get to the point where the feature can be enabled
without relying on implementation details.

This also allows us to do something that was really hard before: we can
enable *just* the indirect call retpolines when using SLH. For x86, we
don't have any other way to mitigate indirect calls. Other architectures
may take a different approach of course, and none of this is surfaced to
user-level flags.

Differential Revision: https://reviews.llvm.org/D51157

llvm-svn: 341363
2018-09-04 12:38:00 +00:00
Chandler Carruth 219888d1b2 [x86/SLH] Teach SLH to harden against the "ret2spec" attack by
implementing the proposed mitigation technique described in the original
design document.

The idea is to check after calls that the return address used to arrive
at that location is in fact the correct address. In the event of
a mis-predicted return which reaches a *valid* return but not the
*correct* return, this will detect the mismatch much like it would
a mispredicted conditional branch.

This is the last published attack vector that I am aware of in the
Spectre v1 space which is not mitigated by SLH+retpolines. However,
don't read *too* much into that: this is an area of ongoing research
where we expect more issues to be discovered in the future, and it also
makes no attempt to mitigate Spectre v4. Still, this is an important
completeness bar for SLH.

The change here is of course delightfully simple. It was predicated on
cutting support for post-instruction symbols into LLVM which was not at
all simple. Many thanks to Hal Finkel, Reid Kleckner, and Justin Bogner
who helped me figure out how to do a bunch of the complex changes
involved there.

Differential Revision: https://reviews.llvm.org/D50837

llvm-svn: 341358
2018-09-04 10:59:10 +00:00
Matthias Braun 4f340e975e Revamp test-suite documentation
- Remove duplication: Both TestingGuide and TestSuiteMakefileGuide
  would give a similar overview over the test-suite.
- Present cmake/lit as the default/normal way of running the test-suite:
- Move information about the cmake/lit testsuite into the new
  TestSuiteGuide.rst file. Mark the remaining information in
  TestSuiteMakefilesGuide.rst as deprecated.
- General simplification and shorting of language.
- Remove paragraphs about tests known to fail as everything should pass
  nowadays.
- Remove paragraph about zlib requirement; it's not required anymore
  since we copied a zlib source snapshot into the test-suite.
- Remove paragraph about comparison with "native compiler". Correctness is
  always checked against reference outputs nowadays.
- Change cmake/lit quickstart section to recommend `pip` for installing
  lit and use `CMAKE_C_COMPILER` and a cache file in the example as that
  is what most people will end up doing anyway. Also a section about
  compare.py to quickstart.
- Document `Bitcode` and `MicroBenchmarks` directories.
- Add section with commonly used cmake configuration options.
- Add section about showing and comparing result files via compare.py.
- Add section about using external benchmark suites.
- Add section about using custom benchmark suites.
- Add section about profile guided optimization.
- Add section about cross-compilation and running on external devices.

Differential Revision: https://reviews.llvm.org/D51465

llvm-svn: 341260
2018-08-31 21:47:01 +00:00
Andrea Di Biagio 8b647dcf4b [llvm-mca] Report the number of dispatched micro opcodes in the DispatchStatistics view.
This patch introduces the following changes to the DispatchStatistics view:
 * DispatchStatistics now reports the number of dispatched opcodes instead of
   the number of dispatched instructions.
 * The "Dynamic Dispatch Stall Cycles" table now also reports the percentage of
   stall cycles against the total simulated cycles.

This change allows users to easily compare dispatch group sizes with the
processor DispatchWidth.
Before this change, it was difficult to correlate the two numbers, since
DispatchStatistics view reported numbers of instructions (instead of opcodes).
DispatchWidth defines the maximum size of a dispatch group in terms of number of
micro opcodes.

The other change introduced by this patch is related to how DispatchStage
generates "instruction dispatch" events.
In particular:
 * There can be multiple dispatch events associated with a same instruction
 * Each dispatch event now encapsulates the number of dispatched micro opcodes.

The number of micro opcodes declared by an instruction may exceed the processor
DispatchWidth. Therefore, we cannot assume that instructions are always fully
dispatched in a single cycle.
DispatchStage knows already how to handle instructions declaring a number of
opcodes bigger that DispatchWidth. However, DispatchStage always emitted a
single instruction dispatch event (during the first simulated dispatch cycle)
for instructions dispatched.

With this patch, DispatchStage now correctly notifies multiple dispatch events
for instructions that cannot be dispatched in a single cycle.

A few views had to be modified. Views can no longer assume that there can only
be one dispatch event per instruction.

Tests (and docs) have been updated.

Differential Revision: https://reviews.llvm.org/D51430

llvm-svn: 341055
2018-08-30 10:50:20 +00:00
Andrea Di Biagio a2eee47450 [llvm-mca] Add fields "Total uOps" and "uOps Per Cycle" to the report generated by the SummaryView.
This patch adds two new fields to the perf report generated by the SummaryView.
Fields are now logically organized into two small groups; only the second group
contains throughput indicators.

Example:
```
Iterations:        100
Instructions:      300
Total Cycles:      414
Total uOps:        700

Dispatch Width:    4
uOps Per Cycle:    1.69
IPC:               0.72
Block RThroughput: 4.0
```

This patch also updates the docs for llvm-mca.
Due to the nature of this change, several tests in the tools/llvm-mca directory
were affected, and had to be updated using script `update_mca_test_checks.py`.

llvm-svn: 340946
2018-08-29 17:56:39 +00:00
Kirill Bobyrev b3caadf5f4 [benchmark] NFC: Turn benchmark ON on all non-Windows buildbots
The problems with benchmark build should be fixed now, but Windows
buildbots still run into errors seemingly because of the bug in
clang-cl. Because of that, benchmark shouldn't be built on Windows at
this point.

llvm-svn: 340905
2018-08-29 08:59:36 +00:00
Dean Michael Berris 41a214759a [XRay][docs] Chrome Trace Viewer Instructions
This patch adds an example on how to generate a Chrome Trace Viewer
loadable trace from an XRay trace.

llvm-svn: 340847
2018-08-28 17:36:30 +00:00
Dean Michael Berris f0a1088afb [XRay][docs] Update instructions
Add `xray_mode=xray-basic` to the list of options in the "further
exploration" section of the doc.

llvm-svn: 340843
2018-08-28 16:46:27 +00:00
Kirill Bobyrev a294dfa837 [benchmark] Stop building benchmarks by default
Although the benchmark regex-related build issue seems to be
fixed, it appears that benchmark library triggers some stage 2 clang-cl
bugs:

http://lab.llvm.org:8011/builders/clang-x86-windows-msvc2015/builds/13495/steps/build%20stage%202/logs/stdio

The only sensible option now is to prevent benchmark library from
building in the default configuration.

llvm-svn: 340836
2018-08-28 15:36:50 +00:00
Kirill Bobyrev 0addd170ab Pull google/benchmark library to the LLVM tree
This patch pulls google/benchmark v1.4.1 into the LLVM tree so that any
project could use it for benchmark generation. A dummy benchmark is
added to `llvm/benchmarks/DummyYAML.cpp` to validate the correctness of
the build process.

The current version does not utilize LLVM LNT and LLVM CMake
infrastructure, but that might be sufficient for most users. Two
introduced CMake variables:

* `LLVM_INCLUDE_BENCHMARKS` (`ON` by default) generates benchmark
  targets
* `LLVM_BUILD_BENCHMARKS` (`OFF` by default) adds generated
  benchmark targets to the list of default LLVM targets (i.e. if `ON`
  benchmarks will be built upon standard build invocation, e.g. `ninja` or
  `make` with no specific targets)

List of modifications:

* `BENCHMARK_ENABLE_TESTING` is disabled
* `BENCHMARK_ENABLE_EXCEPTIONS` is disabled
* `BENCHMARK_ENABLE_INSTALL` is disabled
* `BENCHMARK_ENABLE_GTEST_TESTS` is disabled
* `BENCHMARK_DOWNLOAD_DEPENDENCIES` is disabled

Original discussion can be found here:
http://lists.llvm.org/pipermail/llvm-dev/2018-August/125023.html

Reviewed by: dberris, lebedev.ri

Subscribers: ilya-biryukov, ioeric, EricWF, lebedev.ri, srhines,
dschuff, mgorny, krytarowski, fedor.sergeev, mgrang, jfb, llvm-commits

Differential Revision: https://reviews.llvm.org/D50894

llvm-svn: 340809
2018-08-28 09:42:41 +00:00
Matt Arsenault 937003cf22 LangRef: Clarify expected sNaN behavior for minnum/maxnum
This matches the de-facto behavior based on constant folding
and the default lowering to fmin/fmax.

llvm-svn: 340762
2018-08-27 17:40:07 +00:00
Andrea Di Biagio b89b96c1b2 [llvm-mca] Improved report generated by the SchedulerStatistics view.
Before this patch, the SchedulerStatistics only printed the maximum number of
buffer entries consumed in each scheduler's queue at a given point of the
simulation.

This patch restructures the reported table, and adds an extra field named
"Average number of used buffer entries" to it.
This patch also uses different colors to help identifying bottlenecks caused by
high scheduler's buffer pressure.

llvm-svn: 340746
2018-08-27 14:52:52 +00:00
Chandler Carruth 9ae926b973 [IR] Replace `isa<TerminatorInst>` with `isTerminator()`.
This is a bit awkward in a handful of places where we didn't even have
an instruction and now we have to see if we can build one. But on the
whole, this seems like a win and at worst a reasonable cost for removing
`TerminatorInst`.

All of this is part of the removal of `TerminatorInst` from the
`Instruction` type hierarchy.

llvm-svn: 340701
2018-08-26 09:51:22 +00:00
Kuba Mracek a2e0c2462a [llvm] Document "%T" as deprecated in CommandGuide/lit.rst
Differential Revision: https://reviews.llvm.org/D48842

llvm-svn: 340677
2018-08-25 01:27:48 +00:00
Alexander Richardson 6bcf2ba2f0 Allow creating llvm::Function in non-zero address spaces
Most users won't have to worry about this as all of the
'getOrInsertFunction' functions on Module will default to the program
address space.

An overload has been added to Function::Create to abstract away the
details for most callers.

This is based on https://reviews.llvm.org/D37054 but without the changes to
make passing a Module to Function::Create() mandatory. I have also added
some more tests and fixed the LLParser to accept call instructions for
types in the program address space.

Reviewed By: bjope

Differential Revision: https://reviews.llvm.org/D47541

llvm-svn: 340519
2018-08-23 09:25:17 +00:00
David Green 9dd1d451d9 [AArch64] Add Tiny Code Model for AArch64
This adds the plumbing for the Tiny code model for the AArch64 backend. This,
instead of loading addresses through the normal ADRP;ADD pair used in the Small
model, uses a single ADR. The 21 bit range of an ADR means that the code and
its statically defined symbols need to be within 1MB of each other.

This makes it mostly interesting for embedded applications where we want to fit
as much as we can in as small a space as possible.

Differential Revision: https://reviews.llvm.org/D49673

llvm-svn: 340397
2018-08-22 11:31:39 +00:00
Fangrui Song 61aaa3504f [docs][gold] Fix a typo
llvm-svn: 340335
2018-08-21 21:00:54 +00:00
Alex Langford f37700506f [docs] Fix a small typo in a debug info example
llvm-svn: 340246
2018-08-21 01:43:03 +00:00
Aditya Kumar 6373f5ddee Updating MergeFunctions.rst
Improving readability, removing redundant contents.

Reviewers: hiraditya
Differential Revision: https://reviews.llvm.org/D50686

llvm-svn: 340131
2018-08-18 20:17:19 +00:00
Chandler Carruth 75ca6be1c1 [x86/MIR] Implement support for pre- and post-instruction symbols, as
well as MIR parsing support for `MCSymbol` `MachineOperand`s.

The only real way to test pre- and post-instruction symbol support is to
use them in operands, so I ended up implementing that within the patch
as well. I can split out the operand support if folks really want but it
doesn't really seem worth it.

The functional implementation of pre- and post-instruction symbols is
now *completely trivial*. Two tiny bits of code in the (misnamed)
AsmPrinter. It should be completely target independent as well. We emit
these exactly the same way as we emit basic block labels. Most of the
code here is to give full dumping, MIR printing, and MIR parsing support
so that we can write useful tests.

The MIR parsing of MC symbol operands still isn't 100%, as it forces the
symbols to be non-temporary and non-local symbols with names. However,
those names often can encode most (if not all) of the special semantics
desired, and unnamed symbols seem especially annoying to serialize and
de-serialize. While this isn't perfect or full support, it seems plenty
to write tests that exercise usage of these kinds of operands.

The MIR support for pre-and post-instruction symbols was quite
straightforward. I chose to print them out in an as-if-operand syntax
similar to debug locations as this seemed the cleanest way and let me
use nice introducer tokens rather than inventing more magic punctuation
like we use for memoperands.

However, supporting MIR-based parsing of these symbols caused me to
change the design of the symbol support to allow setting arbitrary
symbols. Without this, I don't see any reasonable way to test things
with MIR.

Differential Revision: https://reviews.llvm.org/D50833

llvm-svn: 339962
2018-08-16 23:11:05 +00:00
Justin Bogner b9fb2aec92 [docs] Try to clarify the FuzzingLLVM docs
Try to improve these docs based on some recent questions that were
sent to llvm-dev:

  http://lists.llvm.org/pipermail/llvm-dev/2018-August/125329.html

llvm-svn: 339949
2018-08-16 21:55:09 +00:00
Aaron Ballman cd27070a05 Update the coding standards and developer policy documentation surrounding whitespace.
Clarify that you should not introduce trailing whitespace when making a commit and that you should not remove trailing whitespace that's unrelated to code you are changing or are about to change. Then clarified the developer policy around what is considered an obvious whitespace commit.

llvm-svn: 339455
2018-08-10 17:26:07 +00:00
Michael Trent 4a68586d9c Add a CommandGuide for llvm-objdump
Summary:
Add a CommandGuide for llvm-objdump summarizing its usage along with some
general context.

Reviewers: beanz

Reviewed By: beanz

Subscribers: Eugene.Zelenko, llvm-commits

Differential Revision: https://reviews.llvm.org/D50034

llvm-svn: 339250
2018-08-08 14:39:22 +00:00
Chandler Carruth c3cc1ec6b1 [docs] Continue working around broken Sphinx parsing of LLVM code blocks
by switching to `text` in another place.

llvm-svn: 339001
2018-08-06 10:20:05 +00:00
Chandler Carruth f98035ce65 [docs] Remove the `dso_local` tag from these functions.
The sphinx build bot is erroring on these examples for some unknown
reason, and really the dso_local doesn't seem to be relevant to the
example in any way so its cleaner to omit it. And now they will look
a bit more like other (successful) IR examples.

llvm-svn: 338998
2018-08-06 10:03:25 +00:00
Chandler Carruth 3a56e3f028 [docs] Stop trying to parse the ThinLTO summary IR fragments with the
`llvm` syntax in Sphinx. This appears to just fail and create errors on
the docs buildbot.

llvm-svn: 338997
2018-08-06 09:46:59 +00:00
Chandler Carruth 4a73aa112b [docs] Switch debug info metadata blocks to use `text` instead of `llvm`
highlighting syntax.

Most of them already were like this, and the Sphinx runs on the docs
build bot seems to be substantially more picky and/or not have support
for a bunch of the syntax here. Hopefully this will let it progress past
this.

My previous attempt to fix the syntax made the `opt` tool happy, but no
idea what the Sphinx stuff is really looking for, and the fact that
other blocks already just use `text` led me to this solution.

llvm-svn: 338983
2018-08-06 03:35:36 +00:00
Chandler Carruth 24dd211f05 [docs] Correct the basic syntax structure of the DISubrange example.
Notably, just close two of the debug info metadata nodes early rather
than leaving them open with `...` which won't ever lex correctly. And
add the missing `:` on the count labels.

Slowly progressing through all of the warnings on the documentation
build bot. Sorry to do this one commit at a time, but despite my best
efforts I can't trigger these errors locally.

llvm-svn: 338982
2018-08-06 02:30:01 +00:00
Chandler Carruth 297620d337 [docs] Remove an example that isn't well formed LLVM IR and trips up the
Sphinx syntax highlighter.

This example also doesn't really make sense. There is no control flow or
clarification of what the `Safe:` block exists to do... If we want
examples here, we should make them much more clear in addition to making
them well formed IR sequences.

llvm-svn: 338981
2018-08-06 02:02:09 +00:00
Chandler Carruth ef705b7de1 [docs] Fix an LLVM-syntax code block to actually be valid LLVM synatx.
Hopefully fixes an issue on the docs build bot.

llvm-svn: 338980
2018-08-06 01:41:25 +00:00
Chandler Carruth 343a87ac8d [docs] Turn of `nasm` highlighting for a code block.
This appears to produce a warning on the docs build bot. It doesn't
reproduce for me, likely because I have a newer (or more full featured)
pygments install.

llvm-svn: 338978
2018-08-06 01:19:43 +00:00
Chandler Carruth 1230d22c59 [docs] Reinstate r337730 - Add support for Markdown documentation in
Sphinx.

We think the bot is updated now, so trying this again. I'm landing it
(with permission) as Michael is at a con at the moment.

Actual patch largely by Michael Spencer.

Differential Revision: https://reviews.llvm.org/D44910

llvm-svn: 338977
2018-08-06 00:38:31 +00:00
Matt Davis b4588e594f [llvm-mca][docs] Move the code marker text into its own subsection. NFC.
Also fixed a few undecorated 'llvm-mca' references to be highlighted
with the 'program' emphasis.

llvm-svn: 338900
2018-08-03 15:56:07 +00:00
Andrea Di Biagio 1c3bcc6ce5 [llvm-mca] Speed up the computation of the wait/ready/issued sets in the Scheduler.
This patch is a follow-up to r338702.

We don't need to use a map to model the wait/ready/issued sets. It is much more
efficient to use a vector instead.

This patch gives us an average 7.5% speedup (on top of the ~12% speedup obtained
after r338702).

llvm-svn: 338883
2018-08-03 12:55:28 +00:00
Andrea Di Biagio eaca8ed5b8 [llvm-mca][docs] Improve the CommandLine documentation.
This patch replaces all the remaining occurrences of string "MCA" with
":program:`llvm-mca`".  Somehow I missed those strings when I committed r338394.

This patch also improves section "Instruction Dispatch".

llvm-svn: 338881
2018-08-03 12:44:56 +00:00
Hans Wennborg 67500081a2 Clear release notes and update version
llvm-svn: 338556
2018-08-01 13:58:00 +00:00
Hans Wennborg 721c9e515c Bump the trunk version to 8.0.0svn
llvm-svn: 338537
2018-08-01 13:25:30 +00:00
Matt Davis e8c70bc187 [llvm-mca][docs] Replace "temporary" with "physical registers". NFC.
llvm-svn: 338415
2018-07-31 18:59:46 +00:00
Andrea Di Biagio 1dac6ba7e2 [llvm-mca][docs] Improve the "How LLVM-MCA works" section.
llvm-svn: 338410
2018-07-31 18:19:15 +00:00
Andrea Di Biagio bdcf6ad60d [llvm-mca][docs] Always use `llvm-mca` in place of `MCA`.
llvm-svn: 338394
2018-07-31 15:29:10 +00:00
Matt Davis 8d253a71c0 [llvm-mca][docs] Add instruction flow documentation. NFC.
Summary:
This patch mostly copies the existing Instruction Flow, and stage descriptions
from the mca README.  I made a few text tweaks, but no semantic changes,
and made reference to the "default pipeline."  I also removed the internals
references (e.g., reference to class names and header files).  I did leave the
LSUnit name around, but only as an abbreviated word for the load-store unit.


Reviewers: andreadb, courbet, RKSimon, gbedwell, filcab

Reviewed By: andreadb

Subscribers: tschuett, jfb, llvm-commits

Differential Revision: https://reviews.llvm.org/D49692

llvm-svn: 338319
2018-07-30 22:30:14 +00:00
Joel Galenson 764b3d8cc5 [doc] Fix Getting Started typo.
This makes it easier for someone to copy-paste this line, change the path, and run the command.

Differential Revision: https://reviews.llvm.org/D49201

llvm-svn: 338254
2018-07-30 15:14:24 +00:00
Vedant Kumar 8a05b01d13 [docs] Clarify role of DIExpressions within debug intrinsics
This should make the semantics of DIExpressions within llvm.dbg.{addr,
declare, value} easier to understand.

Differential Revision: https://reviews.llvm.org/D49572

llvm-svn: 338182
2018-07-28 00:33:47 +00:00
Dmitry Preobrazhensky c80b1650a7 [AMDGPU][MC][DOC] Updated AMD GPU assembler description
llvm-svn: 338125
2018-07-27 14:17:15 +00:00
Craig Topper 05277170a4 [Docs] Remove hard tab character from code block in optbisect documentation
llvm-svn: 338105
2018-07-27 06:54:13 +00:00
Duncan P. N. Exon Smith 0f81faed05 ADT: Document advantages of SmallVector<T,0> over std::vector
In light of the recent changes to SmallVector in r335421, r337514, and
r337820, document its advantages over std::vector (see r175906 and
r266909).

Also add a release note.

https://reviews.llvm.org/D49748

llvm-svn: 338071
2018-07-26 21:29:54 +00:00
David Carlier a796aa4299 [Docs] Update of Xray page
Update of supported oses.

Reviewers: dberris

Reviewed By: dberris

Differential Revision: https://reviews.llvm.org/D49789

llvm-svn: 338003
2018-07-26 04:44:31 +00:00
Eli Friedman 0f522bdbac [LangRef] Clarify undefined behavior for function attributes.
Violating the invariants specified by attributes is undefined behavior.
Maybe we could use poison instead for some of the parameter attributes,
but I don't think it's worthwhile.

Differential Revision: https://reviews.llvm.org/D49041

llvm-svn: 337947
2018-07-25 18:26:38 +00:00
Andres Freund 376a3d3659 Add PerfJITEventListener for perf profiling support.
This new JIT event listener supports generating profiling data for
the linux 'perf' profiling tool, allowing it to generate function and
instruction level profiles.

Currently this functionality is not enabled by default, but must be
enabled with LLVM_USE_PERF=yes.  Given that the listener has no
dependencies, it might be sensible to enable by default once the
initial issues have been shaken out.

I followed existing precedent in registering the listener by default
in lli. Should there be a decision to enable this by default on linux,
that should probably be changed.

Please note that until https://reviews.llvm.org/D47343 is resolved,
using this functionality with mcjit rather than orcjit will not
reliably work.

Disregarding the previous comment, here's an example:

$ cat /tmp/expensive_loop.c

bool stupid_isprime(uint64_t num)
{
        if (num == 2)
                return true;
        if (num < 1 || num % 2 == 0)
                return false;
        for(uint64_t i = 3; i < num / 2; i+= 2) {
                if (num % i == 0)
                        return false;
        }
        return true;
}

int main(int argc, char **argv)
{
        int numprimes = 0;

        for (uint64_t num = argc; num < 100000; num++)
        {
                if (stupid_isprime(num))
                        numprimes++;
        }

        return numprimes;
}

$ clang -ggdb -S -c -emit-llvm /tmp/expensive_loop.c -o
/tmp/expensive_loop.ll

$ perf record -o perf.data -g -k 1 ./bin/lli -jit-kind=mcjit /tmp/expensive_loop.ll 1

$ perf inject --jit -i perf.data -o perf.jit.data

$ perf report -i perf.jit.data
-   92.59%  lli      jitted-5881-2.so                   [.] stupid_isprime
     stupid_isprime
     main
     llvm::MCJIT::runFunction
     llvm::ExecutionEngine::runFunctionAsMain
     main
     __libc_start_main
     0x4bf6258d4c544155
+    0.85%  lli      ld-2.27.so                         [.] do_lookup_x

And line-level annotations also work:
       │              for(uint64_t i = 3; i < num / 2; i+= 2) {
       │1 30:   movq   $0x3,-0x18(%rbp)
  0.03 │1 38:   mov    -0x18(%rbp),%rax
  0.03 │        mov    -0x10(%rbp),%rcx
       │        shr    $0x1,%rcx
  3.63 │     ┌──cmp    %rcx,%rax
       │     ├──jae    6f
       │     │                if (num % i == 0)
  0.03 │     │  mov    -0x10(%rbp),%rax
       │     │  xor    %edx,%edx
 89.00 │     │  divq   -0x18(%rbp)
       │     │  cmp    $0x0,%rdx
  0.22 │     │↓ jne    5f
       │     │                        return false;
       │     │  movb   $0x0,-0x1(%rbp)
       │     │↓ jmp    73
       │     │        }
  3.22 │1 5f:│↓ jmp    61
       │     │        for(uint64_t i = 3; i < num / 2; i+= 2) {

Subscribers: mgorny, llvm-commits

Differential Revision: https://reviews.llvm.org/D44892

llvm-svn: 337789
2018-07-24 00:54:06 +00:00
Matt Davis 07dee81a68 [llvm-mca][docs] Define IPC where it is first mentioned. NFC.
Expand the abbreviation where it is first used, and use IPC elsewhere.

llvm-svn: 337739
2018-07-23 21:10:50 +00:00
Michael J. Spencer 384b317c67 Revert "[docs] Add support for Markdown documentation in Sphinx"
Looks like this bot hasn't been updated yet.

llvm-svn: 337731
2018-07-23 20:00:32 +00:00
Michael J. Spencer 61c7ee42e2 [docs] Add support for Markdown documentation in Sphinx
Differential Revision: https://reviews.llvm.org/D44910

llvm-svn: 337730
2018-07-23 19:49:34 +00:00
Jonas Devlieghere de95704e74 [Docs] Fix LLVM_YAML_IS_DOCUMENT_LIST_VECTOR
The docs incorrectly said to repeat std::vector inside
LLVM_YAML_IS_DOCUMENT_LIST_VECTOR.

llvm-svn: 337695
2018-07-23 14:17:43 +00:00
Matt Davis f2603c0767 [llvm-mca][docs] Add documentation for the statistic outputs from mca. NFC
Summary: The original text was lifted from the MCA README.  I re-ran the dot-product example and updated the output seen in the docs.  I also added a few paragraphs discussing the instruction issued and retired histograms, as well as discussing the register file stats.

Reviewers: andreadb, RKSimon, courbet, gbedwell, filcab

Reviewed By: andreadb

Subscribers: tschuett

Differential Revision: https://reviews.llvm.org/D49614

llvm-svn: 337648
2018-07-21 18:32:47 +00:00
George Karpenkov 346dfbe2bc [FileCheck] Provide an option for FileCheck to dump original input to stderr on failure
The option can be either set using environment variable (e.g. env
FILECHECK_DUMP_INPUT_ON_FAILURE=1 ninja check-fuzzer) or with a
FileCheck flag.

This can be extremely useful for debugging, cf.
https://groups.google.com/forum/#!topic/llvm-dev/kLrzg8OM_h8 for
discussion.

Differential Revision: https://reviews.llvm.org/D49328

llvm-svn: 337609
2018-07-20 20:21:57 +00:00
Michael J. Spencer caefe42c66 Revert "[docs] Add support for Markdown documentation in Sphinx"
The buildbots have an old version of Sphinx (need at least 1.3).  Revert until they are upgraded.

llvm-svn: 337513
2018-07-20 00:24:36 +00:00
Michael J. Spencer 326ffb702a [docs] Add support for Markdown documentation in Sphinx
Differential Revision: https://reviews.llvm.org/D44910

llvm-svn: 337509
2018-07-19 23:40:58 +00:00
Matt Davis bc093ea003 [llvm-mca][docs] Add Timeline and How MCA works.
For the most part, these changes were from the RFC.  I made a few minor
word/structure changes, but nothing significant.  I also regenerated the
example output, and adjusted the text accordingly.

Differential Revision: https://reviews.llvm.org/D49527

llvm-svn: 337496
2018-07-19 20:33:59 +00:00
Matt Morehouse d7df6279e1 [libFuzzer] Update documentation regarding MSan.
Summary: -fsanitize=fuzzer,memory now works out-of-the-box.

Reviewers: kcc

Reviewed By: kcc

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D49441

llvm-svn: 337476
2018-07-19 17:59:11 +00:00
Anastasis Grammenos ad6ff87888 [Docs] Testing Debug Info Preservation in Optimizations
Differential Revision: https://reviews.llvm.org/D49053

llvm-svn: 337457
2018-07-19 14:08:54 +00:00
David Green 7fbf06c10b [UnJ] Document unroll and jam pass and loop metadata
Add some quick words for unroll and jam to the list of passes and add
unroll_and_jam metadata to the language ref.

Differential Revision: https://reviews.llvm.org/D49349

llvm-svn: 337448
2018-07-19 12:37:00 +00:00
Teresa Johnson 4577e9a063 [docs] Update GoldPlugin documentation
Summary:
Updated and reorganized. Made the following additions:
1) How to see if ld.gold is installed, and whether it is the current
default.
2) How to install ld.gold as the default or alternatively use
-fuse-ld=gold.
3) Move the part about installing the newly built ld-new as the default
to the prior section and how to use --enable-gold=default to do it
automatically on install.
4) Add a note about ld.bfd supporting plugins but indicate that it is
not tested by the LLVM project and gold is the recommended linker for
use with the gold plugin.

Fixes PR32760.

Reviewers: davide

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D49490

llvm-svn: 337404
2018-07-18 17:10:17 +00:00
Chandler Carruth f244fada16 [x86/SLH] Add the design document for Speculative Load Hardening,
a Spectre v1 mitigation.

This was initially posted w/ the patch implementing this, got some basic
review there. Also, it is generated from a the Google doc that I shared
as part of the Speculative Load Hardening RFC and which has seen pretty
widespread review at this point.

However, as the patches are landing in LLVM, I wanted to land the docs
as well. But it seemed like a bad idea to have them in the same commit
in case of reverts or other things. So the docs are split out here.

Thanks for all the review so far, and further review and improvements to
the documentation here welcome. Please feel free to keep hammering on
the code review or Google document.

Note that this is a markdown document which Sphinx doesn't yet process.
But we can add support for that after and this should get picked up
(and I'm preparing patches for that). Also, this gets the document
itself into a nice shared place where we can iterate on it.

Differential Revision: https://reviews.llvm.org/D49433

llvm-svn: 337391
2018-07-18 14:05:14 +00:00
Peter Collingbourne 3e22733698 MC: Implement support for new .addrsig and .addrsig_sym directives.
Part of the address-significance tables proposal:
http://lists.llvm.org/pipermail/llvm-dev/2018-May/123514.html

Differential Revision: https://reviews.llvm.org/D47744

llvm-svn: 337328
2018-07-17 22:17:18 +00:00
Eli Friedman e15a111ba0 [LangRef] Clarify semantics of load metadata.
We need to explicitly state what happens when an invariant promised by
load metadata is violated at runtime, since it's come up repeatedly.

It's possible we want to specify that the result of the load is poison
in some cases, rather than undefined behavior, if the constraint is
violated. That would allow preserving the metadata when the load is
hoisted, but doesn't allow propagating metadata based on control flow.
We currently do transforms based on control flow for nonnull metadata
(in PromoteMemToReg).

Differential Revision: https://reviews.llvm.org/D47854

llvm-svn: 337325
2018-07-17 20:38:11 +00:00
Eli Friedman d3a308789e [LangRef] nnan and ninf produce poison.
Clarify that violating nnan and ninf can lead to undefined behavior.
This allows more aggressive optimizations based on those assumptions.

Differential Revision: https://reviews.llvm.org/D47963

llvm-svn: 337323
2018-07-17 20:31:42 +00:00
Eli Friedman 8bb4326c04 [LangRef] Clarify which fast-math flags affect fcmp.
nsz has no effect due to the way fcmp is defined; +0 and -0 compare
equal anyway. reassoc could have the obvious effect.

llvm-svn: 337322
2018-07-17 20:28:31 +00:00
Matt Davis a448670b5b [llvm-mca][docs] Revert mca internals docs.
We're going to work on this in a separate review focusing more on documenting
the View and probably removing some of the less-interesting/less-useful pieces.

This reverts r337219,337225

llvm-svn: 337295
2018-07-17 16:11:54 +00:00
Matt Davis 1c1de45257 [llvm-mca][docs] Add notes about cycle and resource callbacks. NFC.
llvm-svn: 337225
2018-07-16 23:50:53 +00:00
Sanjay Patel c71adc8040 [Intrinsics] define funnel shift IR intrinsics + DAG builder support
As discussed here:
http://lists.llvm.org/pipermail/llvm-dev/2018-May/123292.html
http://lists.llvm.org/pipermail/llvm-dev/2018-July/124400.html

We want to add rotate intrinsics because the IR expansion of that pattern is 4+ instructions, 
and we can lose pieces of the pattern before it gets to the backend. Generalizing the operation 
by allowing 2 different input values (plus the 3rd shift/rotate amount) gives us a "funnel shift" 
operation which may also be a single hardware instruction.

Initially, I thought we needed to define new DAG nodes for these ops, and I spent time working 
on that (much larger patch), but then I concluded that we don't need it. At least as a first 
step, we have all of the backend support necessary to match these ops...because it was required. 
And shepherding these through the IR optimizer is the primary concern, so the IR intrinsics are 
likely all that we'll ever need.

There was also a question about converting the intrinsics to the existing ROTL/ROTR DAG nodes
(along with improving the oversized shift documentation). Again, I don't think that's strictly 
necessary (as the test results here prove). That can be an efficiency improvement as a small 
follow-up patch.

So all we're left with is documentation, definition of the IR intrinsics, and DAG builder support. 

Differential Revision: https://reviews.llvm.org/D49242

llvm-svn: 337221
2018-07-16 22:59:31 +00:00
Matt Davis ed78e85feb [llvm-mca][docs] Initial description of mca internals. NFC
This patch introduces a brief description of the components of MCA.  The main
focus is on Views.   This is a work in progress, and more descriptions will be
introduced later.  I want to flesh-out the Views section more and provide a
detailed description of eventing in MCA.  Eventually a brief code example of a
View should accompany the description.

Also, we should consider moving the MCA internals guide elsewhere at some point.

llvm-svn: 337219
2018-07-16 21:42:58 +00:00
Joel Galenson 4099b249fb [cfi-verify] Abort on unsupported targets
As suggested in the review for r337007, this makes cfi-verify abort on unsupported targets instead of producing incorrect results.  It also updates the design document to reflect this.

Differential Revision: https://reviews.llvm.org/D49304

llvm-svn: 337181
2018-07-16 15:26:44 +00:00
Vedant Kumar 899692e981 [docs] Update usage directive for llvm-cov report -show-functions
llvm-svn: 337062
2018-07-13 22:39:31 +00:00
Joel E. Denny dc5ba317b1 [FileCheck] Implement -v and -vv for tracing matches
-v prints all directive pattern matches.

-vv additionally prints info that might be noise to users but that can
be helpful to FileCheck developers.

To maximize code reuse and to make diagnostics more consistent, this
patch also adjusts and extends some of the existing diagnostics.
CHECK-NOT failures now report variables uses.  Many more diagnostics
now report the check prefix and kind of directive.

Reviewed By: probinson

Differential Revision: https://reviews.llvm.org/D47114

llvm-svn: 336967
2018-07-13 03:08:23 +00:00
Joel E. Denny bcf5b441d8 [FileCheck] Don't permit overlapping CHECK-DAG
That is, make CHECK-DAG skip matches that overlap the matches of any
preceding consecutive CHECK-DAG directives.  This change makes
CHECK-DAG more consistent with other directives, and there is evidence
it makes CHECK-DAG more intuitive and less error-prone.  See the RFC
discussion starting at:

  http://lists.llvm.org/pipermail/llvm-dev/2018-May/123010.html

Moreover, this behavior enables CHECK-DAG groups for unordered,
non-unique strings or patterns.  For example, it is useful for
verifying output or logs from a parallel program, such as the OpenMP
runtime.

This patch also implements the command-line option
-allow-deprecated-dag-overlap, which reverts CHECK-DAG to the old
overlapping behavior.  This option should not be used in new tests.
It is meant only for the existing tests that are broken by this change
and that need time to update.

See the following bugzilla issue for tracking of such tests:

  https://bugs.llvm.org/show_bug.cgi?id=37532

Patches to add -allow-deprecated-dag-overlap to those tests will
follow immediately.

Reviewed By: probinson

Differential Revision: https://reviews.llvm.org/D47106

llvm-svn: 336847
2018-07-11 20:27:27 +00:00
Teresa Johnson b90dd4b25b Revert "[docs] As of binutils 2.21.51.0.2, ld.bfd supports plugins too, represent this in docs"
This reverts commit r306102.

This change was made without any review, and has a couple of issues.
First, AFAIK we do not test the combination of the LLVM gold plugin with
ld.bfd. Second, the change removed documentation for how to build gold
and replaced it with instructions for building ld.bfd.

llvm-svn: 336841
2018-07-11 20:08:32 +00:00
Joel E. Denny 614c986175 Revert r336830: [FileCheck] Don't permit overlapping CHECK-DAG
Companion patches are failing to commit, and this patch alone breaks
many tests.

llvm-svn: 336833
2018-07-11 19:03:00 +00:00
Joel E. Denny edf338856c [FileCheck] Don't permit overlapping CHECK-DAG
That is, make CHECK-DAG skip matches that overlap the matches of any
preceding consecutive CHECK-DAG directives.  This change makes
CHECK-DAG more consistent with other directives, and there is evidence
it makes CHECK-DAG more intuitive and less error-prone.  See the RFC
discussion starting at:

  http://lists.llvm.org/pipermail/llvm-dev/2018-May/123010.html

Moreover, this behavior enables CHECK-DAG groups for unordered,
non-unique strings or patterns.  For example, it is useful for
verifying output or logs from a parallel program, such as the OpenMP
runtime.

This patch also implements the command-line option
-allow-deprecated-dag-overlap, which reverts CHECK-DAG to the old
overlapping behavior.  This option should not be used in new tests.
It is meant only for the existing tests that are broken by this change
and that need time to update.

See the following bugzilla issue for tracking of such tests:

  https://bugs.llvm.org/show_bug.cgi?id=37532

Patches to add -allow-deprecated-dag-overlap to those tests will
follow immediately.

Reviewed By: probinson

Differential Revision: https://reviews.llvm.org/D47106

llvm-svn: 336830
2018-07-11 18:42:58 +00:00
Simon Tatham 6a8c6cadf1 [TableGen] Add a general-purpose JSON backend.
The aim of this backend is to output everything TableGen knows about
the record set, similarly to the default -print-records backend. But
where -print-records produces output in TableGen's input syntax
(convenient for humans to read), this backend produces it as
structured JSON data, which is convenient for loading into standard
scripting languages such as Python, in order to extract information
from the data set in an automated way.

The output data contains a JSON representation of the variable
definitions in output 'def' records, and a few pieces of metadata such
as which of those definitions are tagged with the 'field' prefix and
which defs are derived from which classes. It doesn't dump out
absolutely every piece of knowledge it _could_ produce, such as type
information and complicated arithmetic operator nodes in abstract
superclasses; the main aim is to allow consumers of this JSON dump to
essentially act as new backends, and backends don't generally need to
depend on that kind of data.

The new backend is implemented as an EmitJSON() function similar to
all of llvm-tblgen's other EmitFoo functions, except that it lives in
lib/TableGen instead of utils/TableGen on the basis that I'm expecting
to add it to clang-tblgen too in a future patch.

To test it, I've written a Python script that loads the JSON output
and tests properties of it based on comments in the .td source - more
or less like FileCheck, except that the CHECK: lines have Python
expressions after them instead of textual pattern matches.

Reviewers: nhaehnle

Reviewed By: nhaehnle

Subscribers: arichardson, labath, mgorny, llvm-commits

Differential Revision: https://reviews.llvm.org/D46054

llvm-svn: 336771
2018-07-11 08:40:19 +00:00
Eli Friedman 18f882c8b8 [LangRef] Clarify alloca of zero bytes.
Let's be conservative here; it matches what we actually implemented, and
it should be rare in practice anyway.

Differential Revision: https://reviews.llvm.org/D49042

llvm-svn: 336744
2018-07-11 00:02:01 +00:00
Manoj Gupta 77eeac3d9e llvm: Add support for "-fno-delete-null-pointer-checks"
Summary:
Support for this option is needed for building Linux kernel.
This is a very frequently requested feature by kernel developers.

More details : https://lkml.org/lkml/2018/4/4/601

GCC option description for -fdelete-null-pointer-checks:
This Assume that programs cannot safely dereference null pointers,
and that no code or data element resides at address zero.

-fno-delete-null-pointer-checks is the inverse of this implying that
null pointer dereferencing is not undefined.

This feature is implemented in LLVM IR in this CL as the function attribute
"null-pointer-is-valid"="true" in IR (Under review at D47894).
The CL updates several passes that assumed null pointer dereferencing is
undefined to not optimize when the "null-pointer-is-valid"="true"
attribute is present.

Reviewers: t.p.northover, efriedma, jyknight, chandlerc, rnk, srhines, void, george.burgess.iv

Reviewed By: efriedma, george.burgess.iv

Subscribers: eraman, haicheng, george.burgess.iv, drinkcat, theraven, reames, sanjoy, xbolva00, llvm-commits

Differential Revision: https://reviews.llvm.org/D47895

llvm-svn: 336613
2018-07-09 22:27:23 +00:00
George Burgess IV 3fbfa9c403 Make llvm.objectsize more conservative with null
In non-zero address spaces, we were reporting that an object at `null`
always occupies zero bytes. This is incorrect in many cases, so just
return `unknown` in those cases for now.

Differential Revision: https://reviews.llvm.org/D48860

llvm-svn: 336611
2018-07-09 22:21:16 +00:00
Dave Lee d4f77a523b nm: Add -no-weak flag for hiding weak symbols
Summary:
This adds a new -no-weak flag to nm to hide weak symbols in its output.
This also adds a -W alias for this which is analogous to -U.

Patch by Keith Smiley

Reviewers: kastiglione, enderby, compnerd

Reviewed By: kastiglione

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D48751

llvm-svn: 336126
2018-07-02 17:24:37 +00:00
Piotr Padlewski 5b3db45e8f Implement strip.invariant.group
Summary:
This patch introduce new intrinsic -
strip.invariant.group that was described in the
RFC: Devirtualization v2

Reviewers: rsmith, hfinkel, nlopes, sanjoy, amharc, kuhar

Subscribers: arsenm, nhaehnle, JDevlieghere, hiraditya, xbolva00, llvm-commits

Differential Revision: https://reviews.llvm.org/D47103

Co-authored-by: Krzysztof Pszeniczny <krzysztof.pszeniczny@gmail.com>
llvm-svn: 336073
2018-07-02 04:49:30 +00:00
Paul Robinson bc0748e812 Document the git config for Windows to do line-endings correctly.
Differential Revision: https://reviews.llvm.org/D48494

llvm-svn: 335775
2018-06-27 19:58:28 +00:00
James Henderson c307b00348 Fix doc title underlining.
llvm-svn: 335615
2018-06-26 15:29:09 +00:00
James Henderson 5507f6688d [FileCheck] Add CHECK-EMPTY directive for checking for blank lines
Prior to this change, there was no clean way of getting FileCheck to
check that a line is completely empty. The expected way of using
"CHECK: {{^$}}" does not work because the '^' matches the end of the
previous match (this behaviour may be desirable in certain instances).
For the same reason, "CHECK-NEXT: {{^$}}" will fail when the previous
match was at the end of the line, as the pattern will match there.
Using the recommended [[:space:]] to match an explicit new line could
also match a space, and thus is not always desired. Literal '\n'
matches also do not work. A workaround was suggested in the review, but
it is a little clunky.

This change adds a new directive that behaves the same as CHECK-NEXT,
except that it only matches against empty lines (nothing, not even
whitespace, is allowed). As with CHECK-NEXT, it will fail if more than
one newline occurs before the next blank line. Example usage:
; test.txt
foo

bar
; CHECK: foo
; CHECK-EMPTY:
; CHECK-NEXT: bar

Differential Revision: https://reviews.llvm.org/D28896

Reviewed by: probinson

llvm-svn: 335613
2018-06-26 15:15:45 +00:00
Fangrui Song 05f6626fc4 [docs] Update doc after split of -gen-intrinsic in r335407
llvm-svn: 335515
2018-06-25 19:40:08 +00:00