631 Commits

Author SHA1 Message Date
Mehdi Amini
bf9cc1bd93 ThreadPool unittest: reimplement concurrency test, deterministically this time.
Follow-up to r256056.

From: Mehdi Amini <mehdi.amini@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256087 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-19 05:12:07 +00:00
Teresa Johnson
21577c0682 Remove possibility of failures to due race in ThreadPool unittest
Remove all checks that required main thread to run faster than tasks in
ThreadPool, and yields which are now unnecessary. This should fix some
bot failures.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256056 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-18 22:59:35 +00:00
James Y Knight
ca5c277bdf Rewrite the TrailingObjects template to provide two new features:
- Automatic alignment of the base type for the alignment requirements
   of the trailing types.

 - Support for an arbitrary numbers of trailing types, instead of only
   1 or 2, by using a variadic template implementation.

Upcoming commits to clang will take advantage of both of these features.

Differential Revision: http://reviews.llvm.org/D12439

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256054 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-18 22:54:37 +00:00
NAKAMURA Takumi
ce00641ac5 BranchProbabilityTest.cpp: Suppress warnings. [-Wsign-compare]
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255940 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-18 00:18:18 +00:00
Cong Hou
4c24184936 [BranchProbability] Remove the restriction that known and unknown probabilities cannot coexist when being normalized.
The current BranchProbability::normalizeProbabilities() forbids known and
unknown probabilities to coexist in the list. This was once used to help
capture probability exceptions but has caused some reported build
failures (https://llvm.org/bugs/show_bug.cgi?id=25838).

This patch removes this restriction by evenly distributing the complement
of the sum of all known probabilities to unknown ones. We could still
treat this as an abnormal behavior, but it is better to emit warnings in
our future profile validator.


Differential revision: http://reviews.llvm.org/D15548




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255934 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-17 22:27:07 +00:00
Mehdi Amini
18d1bc23ab Mark ThreadPool unittests as unsupported on PowerPC64
Bots are crashing unexpectingly, see: https://llvm.org/bugs/show_bug.cgi?id=25829

From: Mehdi Amini <mehdi.amini@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255633 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-15 09:10:28 +00:00
Mehdi Amini
41f711c3a3 ThreadPool unittest: add a rough mechanism to mark UNSUPPORTED on a given platform
From: Mehdi Amini <mehdi.amini@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255632 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-15 09:10:25 +00:00
Cong Hou
08224c0a7e Replace the unit test of BranchProbability::normalizeEdgeWeights() with BranchProbability::normalizeProbabilities().
BranchProbability::normalizeEdgeWeights() is going to be retired soon.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255618 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-15 05:25:27 +00:00
Teresa Johnson
cbfe414189 Fix template parameter pack handling in ThreadPool
Fixes passing of template parameter pack via std::forward and add
unittest.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255617 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-15 04:44:02 +00:00
Mehdi Amini
abb30d1a45 Add a C++11 ThreadPool implementation in LLVM
This is a very simple implementation of a thread pool using C++11
thread. It accepts any std::function<void()> for asynchronous
execution. Individual task can be synchronize using the returned
future, or the client can block on the full queue completion.

In case LLVM is configured with Threading disabled, it falls back
to sequential execution using std::async with launch:deferred.

This is intended to support parallelism for ThinLTO processing in
linker plugin, but is generic enough for any other uses.

This is a recommit of r255444 ; trying to workaround a bug in the
MSVC 2013 standard library. I think I was hit by:

 http://connect.microsoft.com/VisualStudio/feedbackdetail/view/791185/std-packaged-task-t-where-t-is-void-or-a-reference-class-are-not-movable

Recommit of r255589, trying to please g++ as well.

Differential Revision: http://reviews.llvm.org/D15464

From: mehdi_amini <mehdi_amini@91177308-0d34-0410-b5e6-96231b3b80d8>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255593 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-15 00:59:19 +00:00
Mehdi Amini
8d176bbf50 Revert "Add a C++11 ThreadPool implementation in LLVM"
This reverts commit r255589. Breaks g++

From: Mehdi Amini <mehdi.amini@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255591 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-15 00:42:44 +00:00
Mehdi Amini
04d774cd38 Add a C++11 ThreadPool implementation in LLVM
This is a very simple implementation of a thread pool using C++11
thread. It accepts any std::function<void()> for asynchronous
execution. Individual task can be synchronize using the returned
future, or the client can block on the full queue completion.

In case LLVM is configured with Threading disabled, it falls back
to sequential execution using std::async with launch:deferred.

This is intended to support parallelism for ThinLTO processing in
linker plugin, but is generic enough for any other uses.

This is a recommit of r255444 ; trying to workaround a bug in the
MSVC 2013 standard library. I think I was hit by:

 http://connect.microsoft.com/VisualStudio/feedbackdetail/view/791185/std-packaged-task-t-where-t-is-void-or-a-reference-class-are-not-movable

Differential Revision: http://reviews.llvm.org/D15464

From: Mehdi Amini <mehdi.amini@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255589 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-15 00:38:05 +00:00
Nico Weber
205d072f69 Revert r255444.
It doesn't build on Windows and broke the Windows LLD and LLDB bots:
http://lab.llvm.org:8011/builders/lld-x86_64-win7/builds/27693/steps/build_Lld/logs/stdio
http://lab.llvm.org:8011/builders/lldb-x86-windows-msvc/builds/13468/steps/build/logs/stdio


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255446 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-13 04:14:39 +00:00
Mehdi Amini
517dd66ae3 Add a C++11 ThreadPool implementation in LLVM
This is a very simple implementation of a thread pool using C++11
thread. It accepts any std::function<void()> for asynchronous
execution. Individual task can be synchronize using the returned
future, or the client can block on the full queue completion.

In case LLVM is configured with Threading disabled, it falls back
to sequential execution using std::async with launch:deferred.

This is intended to support parallelism for ThinLTO processing in
linker plugin, but is generic enough for any other uses.

Differential Revision: http://reviews.llvm.org/D15464

From: Mehdi Amini <mehdi.amini@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255444 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-12 22:55:25 +00:00
Nathan Slingerland
09a7daad01 [Support] Change SaturatingAdd()/SaturatingMultiply() to use pointer for returning overflow state
Summary:
Improve SaturatingAdd()/SaturatingMultiply() to use bool * to optionally return overflow result.
This should make it clearer that the value is returned at callsites and reduces the size of the implementation.

Reviewers: davidxl, silvas

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D15219

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255128 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-09 17:11:28 +00:00
Nathan Slingerland
0197bd6d5e [Support] Add optional argument to SaturatingAdd() and SaturatingMultiply() to indicate that overflow occurred
Summary: Adds the ability for callers to detect when saturation occurred on the result of saturating addition/multiplication.

Reviewers: davidxl, silvas, rsmith

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D14931

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253921 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-23 21:54:22 +00:00
Nathan Slingerland
f2bc179203 [Support] Fix SaturatingMultiply<T>() to be correct (and fast), Re-enable Unit Tests
Summary:
This change fixes the SaturatingMultiply<T>() function template to not cause undefined behavior with T=uint16_t.
Thanks to Richard Smith's contribution, it also no longer requires an integer division.

Patch by Richard Smith.

Reviewers: silvas, davidxl

Subscribers: rsmith, davidxl, llvm-commits

Differential Revision: http://reviews.llvm.org/D14845

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253870 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-23 15:33:43 +00:00
Daniel Sanders
0bee4edf8c Revert the revert 253497 and 253539 - These commits aren't the cause of the clang-cmake-mips failures.
Sorry for the noise.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253662 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-20 13:13:53 +00:00
Daniel Sanders
0a3cc8fdf5 Revert 253497 and 253539 to try to fix clang-cmake-mips buildbot.
It caused link errors of the form:
InstrProfiling.c:(.text.__llvm_profile_instrument_target+0x1c0): undefined reference to `__sync_fetch_and_add_8'

We had a network outage at the time of the commit so the first build to show a
problem is http://lab.llvm.org:8011/builders/clang-cmake-mips/builds/10827



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253656 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-20 10:07:11 +00:00
Nathan Slingerland
0171b5136f [Support] Disable SaturatingMultiply() unit test while investigating
Ubsan detected undefined behavior in the MathExtras SaturatingMultiply test.

This change disables the test while it is being investigated.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253539 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-19 05:20:17 +00:00
Nathan Slingerland
156d5ee497 [llvm-profdata] Add SaturatingAdd/SaturatingMultiply Helper Functions (2nd try)
Summary:
This change adds MathExtras helper functions for handling unsigned, saturating addition and multiplication. It also updates the instrumentation and sample profile merge implementations to use them.

Reviewers: dnovillo, bogner, davidxl

Subscribers: davidxl, llvm-commits

Differential Revision: http://reviews.llvm.org/D14720

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253497 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-18 20:40:41 +00:00
Nathan Slingerland
d4cf58476e Revert "[llvm-profdata] Add SaturatingAdd/SaturatingMultiply Helper Functions"
Not ready for merge.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253415 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-18 00:55:15 +00:00
Nathan Slingerland
4918b66f84 [llvm-profdata] Add SaturatingAdd/SaturatingMultiply Helper Functions
Summary:
This change adds MathExtras helper functions for handling unsigned, saturating addition and multiplication. It also updates the instrumentation and sample profile merge implementations to use them.

No functional changes.

Reviewers: dnovillo, bogner, davidxl

Subscribers: davidxl, llvm-commits

Differential Revision: http://reviews.llvm.org/D14720

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253412 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-18 00:52:43 +00:00
Rafael Espindola
9f7d480d96 Remove excess white space
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253408 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-18 00:31:34 +00:00
David Blaikie
358918e8dd Fix -Wunused-function in a non-Win32 build
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253373 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-17 20:38:54 +00:00
David Blaikie
034f865664 StringRef-ify some Option APIs
Patch by Eugene Kosov!

Differential Revision: http://reviews.llvm.org/D14711

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253360 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-17 19:00:52 +00:00
Pawel Bylica
790e8d91ff [Support] Tweak path::system_temp_directory() on Windows.
Summary:
This patch changes the behavior of path::system_temp_directory() on Windows to be closer to GetTempPath Windows API call. Enforces path separator to be the native one, makes path absolute, etc. GetTempPath is not used directly because of limitations/implementation bugs on Windows 7.

Windows specific unit tests are added. Most of them runs in separated process with modified environment variables.

This change fixes FileSystemTest.CreateDir unittest that had been failing when run from Unix-like shell on Windows (Unix-like path separator (/) used in env variables).

Reviewers: chapuni, rafael, aaron.ballman

Subscribers: rafael, llvm-commits

Differential Revision: http://reviews.llvm.org/D14231

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253345 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-17 16:54:32 +00:00
Rafael Espindola
96902bf6e3 Add MemoryBufferRef(MemoryBuffer&) constructor.
patch by Jonathan Anderson!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253311 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-17 05:11:44 +00:00
Mike Aizatsky
da4cf2cda9 Windows-specific test for sys::path::remove_dots.
Differential Revision: http://reviews.llvm.org/D14503

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@252504 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-09 19:36:53 +00:00
Mike Aizatsky
8cda80ad24 Moving FileManager::removeDotPaths to llvm::sys::path::remove_dots
Differential Revision: http://reviews.llvm.org/D14393

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@252499 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-09 18:56:31 +00:00
Pawel Bylica
6bd362c2d9 Revert r252366: [Support] Use GetTempDir to get the temporary dir path on Windows.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@252367 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-06 23:44:23 +00:00
Pawel Bylica
dae382206c [Support] Use GetTempDir to get the temporary dir path on Windows.
Summary:
In general GetTempDir follows the same logic as the replaced code: checks env variables TMP, TEMP, USERPROFILE in order. However, it also perform other checks like making separators native (\), making the path absolute, etc.

This change fixes FileSystemTest.CreateDir unittest that had been failing when run from Unix-like shell on Windows (Unix-like path separator (/) used in env variables).

Reviewers: chapuni, rafael, aaron.ballman

Subscribers: rafael, llvm-commits

Differential Revision: http://reviews.llvm.org/D14231

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@252366 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-06 23:21:49 +00:00
Pawel Bylica
7561231bee Fix unit tests on Windows: handle env vars with non-ASCII chars.
Summary: On Windows we have to take UTF16 encoded env vars and convert them to UTF8. This patch fixes CopyEnvironment helper function used by process unit tests.

Reviewers: yaron.keren

Subscribers: yaron.keren, llvm-commits

Differential Revision: http://reviews.llvm.org/D14278

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@252039 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-04 08:25:20 +00:00
Pawel Bylica
8bd55b5451 [Support] Extend sys::path with user_cache_directory function.
Summary:
The new function sys::path::user_cache_directory tries to discover
a directory suitable for cache storage for current system user.

On Windows and Darwin it returns a path to system-specific user cache directory.

On Linux it follows XDG Base Directory Specification, what is:
- use non-empty $XDG_CACHE_HOME env var,
- use $HOME/.cache.

Reviewers: chapuni, aaron.ballman, rafael

Subscribers: rafael, aaron.ballman, llvm-commits

Differential Revision: http://reviews.llvm.org/D13801

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251784 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-02 09:49:17 +00:00
Pawel Bylica
947464d179 Fix path::home_directory() unit test.
It turns out that constructing std::string from null pointer is not the very best idea.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@250506 91177308-0d34-0410-b5e6-96231b3b80d8
2015-10-16 10:11:07 +00:00
NAKAMURA Takumi
054dd43f8f SupportTests::HomeDirectory: Don't try tests when $HOME is undefined.
Lit sanitizes env vars. $HOME is not exported in Lit tests.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@250505 91177308-0d34-0410-b5e6-96231b3b80d8
2015-10-16 09:40:01 +00:00
NAKAMURA Takumi
d332f5867b Reformat.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@250504 91177308-0d34-0410-b5e6-96231b3b80d8
2015-10-16 09:38:49 +00:00
Pawel Bylica
2f01bc86e5 Use Windows Vista API to get the user's home directory
Summary: This patch replaces usage of deprecated SHGetFolderPathW with SHGetKnownFolderPath. The usage of SHGetKnownFolderPath is wrapped to allow queries for other "known" folders in the near future.

Reviewers: aaron.ballman, gbedwell

Subscribers: chapuni, llvm-commits

Differential Revision: http://reviews.llvm.org/D13753

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@250501 91177308-0d34-0410-b5e6-96231b3b80d8
2015-10-16 09:08:59 +00:00
Manman Ren
0f34207b1d Recommit r250345, it was reverted in r250366 to investigate a bot failure.
Our internal bot is still red after r250366.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@250415 91177308-0d34-0410-b5e6-96231b3b80d8
2015-10-15 14:59:40 +00:00
Manman Ren
9b380854cd Temporarily revert r250345 to sort out bot failure.
With r250345 and r250343, we start to observe the following failure
when bootstrap clang with lto and pgo:
PHI node entries do not match predecessors!
  %.sroa.029.3.i = phi %"class.llvm::SDNode.13298"* [ null, %30953 ], [ null, %31017 ], [ null, %30998 ], [ null, %_ZN4llvm8dyn_castINS_14ConstantSDNodeENS_7SDValueEEENS_10cast_rettyIT_T0_E8ret_typeERS5_.exit.i.1804 ], [ null, %30975 ], [ null, %30991 ], [ null, %_ZNK4llvm3EVT13getScalarTypeEv.exit.i.1812 ], [ %..sroa.029.0.i, %_ZN4llvm11SmallVectorIiLj8EED1Ev.exit.i.1826 ], !dbg !451895
label %30998
label %_ZNK4llvm3EVTeqES0_.exit19.thread.i
LLVM ERROR: Broken function found, compilation aborted!

I will re-commit this if the bot does not recover.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@250366 91177308-0d34-0410-b5e6-96231b3b80d8
2015-10-15 04:58:24 +00:00
Cong Hou
a99158bbd8 Update the branch weight metadata in JumpThreading pass.
Currently in JumpThreading pass, the branch weight metadata is not updated after CFG modification. Consider the jump threading on PredBB, BB, and SuccBB. After jump threading, the weight on BB->SuccBB should be adjusted as some of it is contributed by the edge PredBB->BB, which doesn't exist anymore. This patch tries to update the edge weight in metadata on BB->SuccBB by scaling it by 1 - Freq(PredBB->BB) / Freq(BB->SuccBB).

This is the third attempt to submit this patch, while the first two led to failures in some FDO tests. After investigation, it is the edge weight normalization that caused those failures. In this patch the edge weight normalization is fixed so that there is no zero weight in the output and the sum of all weights can fit in 32-bit integer. Several unit tests are added.

Differential revision: http://reviews.llvm.org/D10979



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@250345 91177308-0d34-0410-b5e6-96231b3b80d8
2015-10-14 23:14:17 +00:00
Cong Hou
7ebb1848c3 Add - and -= operators to BlockFrequency using saturating arithmetic.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@250077 91177308-0d34-0410-b5e6-96231b3b80d8
2015-10-12 18:34:00 +00:00
Greg Bedwell
d02add1701 Fix rename() sometimes failing if another process uses openFileForRead()
On Windows, fs::rename() could fail is another process was reading the
file at the same time using fs::openFileForRead().  In most cases the user
wouldn't notice as fs::rename() will continue to retry for 2000ms.  Typically
this is enough for the read to complete and a retry to succeed, but if the
disk is being it too hard then the response time might be longer than the
retry time and the rename would fail with a permission error.

Add FILE_SHARE_DELETE to the sharing flags for CreateFileW() in
fs::openFileForRead() and try ReplaceFileW() prior to MoveFileExW()
in fs::rename().

Based on an initial patch by Edd Dawson!

Differential Revision: http://reviews.llvm.org/D13647

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@250046 91177308-0d34-0410-b5e6-96231b3b80d8
2015-10-12 15:11:47 +00:00
Teresa Johnson
a8d99b7b3d Fix another UBSan test error from r248897 and follow on fix r249689
While here fix a few more issues with potential overflow and add
new tests for these cases. Ensured that test now passes with UBSan.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@249745 91177308-0d34-0410-b5e6-96231b3b80d8
2015-10-08 20:52:23 +00:00
Benjamin Kramer
60fe48f866 Make test resilient against windows path separators.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@249320 91177308-0d34-0410-b5e6-96231b3b80d8
2015-10-05 14:15:13 +00:00
Benjamin Kramer
9fdd48c184 [Support] Add a version of fs::make_absolute with a custom CWD.
This will be used soon from clang.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@249309 91177308-0d34-0410-b5e6-96231b3b80d8
2015-10-05 13:02:43 +00:00
Teresa Johnson
9260ee0d88 Add support for sub-byte aligned writes to lib/Support/Endian.h
Summary:
As per Duncan's review for D12536, I extracted the sub-byte bit aligned
reading and writing code into lib/Support, and generalized it. Added calls from
BackpatchWord. Also added unittests.

Reviewers: dexonsmith

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D13189

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@248897 91177308-0d34-0410-b5e6-96231b3b80d8
2015-09-30 13:20:37 +00:00
Maksim Panchenko
3b3752c898 HHVM calling conventions.
HHVM calling convention, hhvmcc, is used by HHVM JIT for
functions in translated cache. We currently support LLVM back end to
generate code for X86-64 and may support other architectures in the
future.

In HHVM calling convention any GP register could be used to pass and
return values, with the exception of R12 which is reserved for
thread-local area and is callee-saved. Other than R12, we always
pass RBX and RBP as args, which are our virtual machine's stack pointer
and frame pointer respectively.

When we enter translation cache via hhvmcc function, we expect
the stack to be aligned at 16 bytes, i.e. skewed by 8 bytes as opposed
to standard ABI alignment. This affects stack object alignment and stack
adjustments for function calls.

One extra calling convention, hhvm_ccc, is used to call C++ helpers from
HHVM's translation cache. It is almost identical to standard C calling
convention with an exception of first argument which is passed in RBP
(before we use RDI, RSI, etc.)

Differential Revision: http://reviews.llvm.org/D12681

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@248832 91177308-0d34-0410-b5e6-96231b3b80d8
2015-09-29 22:09:16 +00:00
Cong Hou
fed6bd8617 Use fixed-point representation for BranchProbability.
BranchProbability now is represented by its numerator and denominator in uint32_t type. This patch changes this representation into a fixed point that is represented by the numerator in uint32_t type and a constant denominator 1<<31. This is quite similar to the representation of BlockMass in BlockFrequencyInfoImpl.h. There are several pros and cons of this change:

Pros:

1. It uses only a half space of the current one.
2. Some operations are much faster like plus, subtraction, comparison, and scaling by an integer.

Cons:

1. Constructing a probability using arbitrary numerator and denominator needs additional calculations.
2. It is a little less precise than before as we use a fixed denominator. For example, 1 - 1/3 may not be exactly identical to 1 / 3 (this will lead to many BranchProbability unit test failures). This should not matter when we only use it for branch probability. If we use it like a rational value for some precise calculations we may need another construct like ValueRatio.

One important reason for this change is that we propose to store branch probabilities instead of edge weights in MachineBasicBlock. We also want clients to use probability instead of weight when adding successors to a MBB. The current BranchProbability has more space which may be a concern.

Differential revision: http://reviews.llvm.org/D12603



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@248633 91177308-0d34-0410-b5e6-96231b3b80d8
2015-09-25 23:09:59 +00:00
Cong Hou
e5457136e7 Pass BranchProbability/BlockMass by value instead of const& as they are small. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@247357 91177308-0d34-0410-b5e6-96231b3b80d8
2015-09-10 23:10:42 +00:00