Commit Graph

10629 Commits

Author SHA1 Message Date
Alexey Samsonov
d976d43f23 Introduce factory methods for SpecialCaseList
Summary:
Doing work in constructors is bad: this change suggests to
call SpecialCaseList::create(Path, Error) instead of
"new SpecialCaseList(Path)". Currently the latter may crash with
report_fatal_error, which is undesirable - sometimes we want to report
the error to user gracefully - for example, if he provides an incorrect
file as an argument of Clang's -fsanitize-blacklist flag.

Reviewers: pcc

Reviewed By: pcc

CC: llvm-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D1327

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188156 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-12 07:49:36 +00:00
Richard Sandiford
23331c30ae Fix big-endian handling of integer-to-vector bitcasts in InstCombine
These functions used to assume that the lsb of an integer corresponds
to vector element 0, whereas for big-endian it's the other way around:
the msb is in the first element and the lsb is in the last element.

Fixes MultiSource/Benchmarks/mediabench/gsm/toast for z.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188155 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-12 07:26:09 +00:00
Chandler Carruth
5b854f1ea5 Re-instate r187323 which fast-tracks promotable allocas as soon as the
SROA-based analysis has enough information. This should work now that
both mem2reg *and* the SSAUpdater-based AllocaPromoter have been updated
to be able to promote the types of allocas that the SROA analysis
detects.

I've included tests for the AllocaPromoter that were only possible to
write once we fast-tracked promotable allocas without rewriting them.
This includes a test both for r187347 and r188145.

Original commit log for r187323:
"""
Now that mem2reg understands how to cope with a slightly wider set of uses of
an alloca, we can pre-compute promotability while analyzing an alloca for
splitting in SROA. That lets us short-circuit the common case of a bunch of
trivially promotable allocas. This cuts 20% to 30% off the run time of SROA for
typical frontend-generated IR sequneces I'm seeing. It gets the new SROA to
within 20% of ScalarRepl for such code. My current benchmark for these numbers
is PR15412, but it fits the general pattern of IR emitted by Clang so it should
be widely applicable.
"""

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188146 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-11 02:17:11 +00:00
Chandler Carruth
37508bb842 Finish fixing the SSAUpdater-based AllocaPromoter strategy in SROA to cope with
the more general set of patterns that are now handled by mem2reg and that we
can detect quickly while doing SROA's initial analysis. Notably, this allows it
to promote through no-op bitcast and GEP sequences. A core part of the
SSAUpdater approach is the ability to test whether a particular instruction is
part of the set being promoted. Testing this becomes significantly more complex
in the world where the operand to every load and store isn't the alloca itself.
I ended up using the approach of walking up the def-chain until we find the
alloca. I benchmarked this against keeping a set of pointer operands and
keeping a set of the loads and stores we care about, and this one seemed faster
although the difference was very small.

No test case yet because currently the rewriting always "fixes" the inputs to
not require this. The next patch which re-enables early promotion of easy cases
in SROA will include a test case that specifically exercises this aspect of the
alloca promoter.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188145 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-11 01:56:15 +00:00
Chandler Carruth
3c7a446059 Reformat some bits of AllocaPromoter and simplify the name and type of
our visiting datastructures in the AllocaPromoter/SSAUpdater path of
SROA. Also shift the order if clears around to be more consistent.

No functionality changed here, this is just a cleanup.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188144 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-11 01:03:18 +00:00
Arnold Schwaighofer
5cf14916c3 Revert r188119 "Kill some duplicated code for removing unreachable BBs."
It is breaking builbots with libgmalloc enabled on Mac OS X.

$ cd llvm ; mkdir release ; cd release
$ ../configure --enable-optimized —prefix=$PWD/install
$ make
$ make check
$ Release+Asserts/bin/llvm-lit -v --param use_gmalloc=1 --param \
  gmalloc_path=/usr/lib/libgmalloc.dylib \
  ../test/Instrumentation/DataFlowSanitizer/args-unreachable-bb.ll

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188142 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-10 20:16:06 +00:00
Michael Gottesman
3ed7576a3b [objc-arc] Track if we encountered an additive overflow while computing {TopDown,BottomUp}PathCounts and do nothing if it occurred.
I fixed the aforementioned problems that came up on some of the linux boxes.
Major thanks to Nick Lewycky for his help debugging!

rdar://14590914

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188122 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-09 23:22:27 +00:00
Peter Collingbourne
835738ce54 Kill some duplicated code for removing unreachable BBs.
This moves removeUnreachableBlocksFromFn from SimplifyCFGPass.cpp
to Utils/Local.cpp and uses it to replace the implementation of
llvm::removeUnreachableBlocks, which appears to do a strict subset
of what removeUnreachableBlocksFromFn does.

Differential Revision: http://llvm-reviews.chandlerc.com/D1334

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188119 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-09 22:47:24 +00:00
Peter Collingbourne
aaae6e9cb8 DataFlowSanitizer: Remove unreachable BBs so IR continues to verify
under the args ABI.

Differential Revision: http://llvm-reviews.chandlerc.com/D1316

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188113 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-09 21:42:53 +00:00
Jakub Staszak
4c71064129 Mark obviously const methods. Also use reference for parameters when possible.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188103 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-09 20:53:48 +00:00
Michael Gottesman
35b6edfbea Revert "[objc-arc] Track if we encountered an additive overflow while computing {TopDown,BottomUp}PathCounts and do nothing if it occured."
This reverts commit r187941.

The commit was passing on my os x box, but it is failing on some non-osx
platforms. I do not have time to look into it now, so I am reverting and will
recommit after I figure this out.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187946 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-08 00:41:18 +00:00
Peter Collingbourne
46c72c74cf Fix ARM build.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187944 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-08 00:15:27 +00:00
Michael Gottesman
7f1a7d4137 [objc-arc] Track if we encountered an additive overflow while computing {TopDown,BottomUp}PathCounts and do nothing if it occured.
rdar://14590914

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187941 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-07 23:56:41 +00:00
Michael Gottesman
b0fd15f645 [objc-arc] Change 4 iterator methods which return const_iterators to be const methods.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187940 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-07 23:56:34 +00:00
Hal Finkel
41418d17cc Add ISD::FROUND for libm round()
All libm floating-point rounding functions, except for round(), had their own
ISD nodes. Recent PowerPC cores have an instruction for round(), and so here I'm
adding ISD::FROUND so that round() can be custom lowered as well.

For the most part, this is straightforward. I've added an intrinsic
and a matching ISD node just like those for nearbyint() and friends. The
SelectionDAG pattern I've named frnd (because ISD::FP_ROUND has already claimed
fround).

This will be used by the PowerPC backend in a follow-up commit.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187926 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-07 22:49:12 +00:00
Peter Collingbourne
6fa33f5dd9 DataFlowSanitizer; LLVM changes.
DataFlowSanitizer is a generalised dynamic data flow analysis.

Unlike other Sanitizer tools, this tool is not designed to detect a
specific class of bugs on its own.  Instead, it provides a generic
dynamic data flow analysis framework to be used by clients to help
detect application-specific issues within their own code.

Differential Revision: http://llvm-reviews.chandlerc.com/D965

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187923 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-07 22:47:18 +00:00
Benjamin Kramer
c11b107f21 JumpThreading: Turn a select instruction into branching if it allows to thread one half of the select.
This is a common pattern coming out of simplifycfg generating gross code.

a:                                       ; preds = %entry
  %sel = select i1 %cmp1, double %add, double 0.000000e+00
  br label %b

b:
  %cond5 = phi double [ %sel, %a ], [ %sub, %entry ]
  %cmp6 = fcmp oeq double %cond5, 0.000000e+00
  br i1 %cmp6, label %if.then, label %if.end

becomes

a:
  br i1 %cmp1, label %b, label %if.then

b:
  %cond5 = phi double [ %sub, %entry ], [ %add, %a ]
  %cmp6 = fcmp oeq double %cond5, 0.000000e+00
  br i1 %cmp6, label %if.then, label %if.end

Skipping block b completely if possible.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187880 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-07 10:29:38 +00:00
Bill Wendling
55a1a590bf Change the linkage of these global values to 'internal'.
The globals being generated here were given the 'private' linkage type. However,
this caused them to end up in different sections with the wrong prefix. E.g.,
they would be in the __TEXT,__const section with an 'L' prefix instead of an 'l'
(lowercase ell) prefix.

The problem is that the linker will eat a literal label with 'L'. If a weak
symbol is then placed into the __TEXT,__const section near that literal, then it
cannot distinguish between the literal and the weak symbol.

Part of the problems here was introduced because the address sanitizer converted
some C strings into constant initializers with trailing nuls. (Thus putting them
in the __const section with the wrong prefix.) The others were variables that
the address sanitizer created but simply had the wrong linkage type.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187827 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-06 22:52:42 +00:00
Arnold Schwaighofer
2d66d4cf42 LoopVectorize: Allow vectorization of loops with lifetime markers
Patch by Marc Jessome!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187825 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-06 22:37:52 +00:00
Jakub Staszak
7198ee6f62 Adjust file to the coding standard.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187808 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-06 17:03:42 +00:00
Serge Pavlov
900cbf5545 Unbreak Debug build on Windows
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187786 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-06 08:44:18 +00:00
Tom Stellard
01d7203ef8 Factor FlattenCFG out from SimplifyCFG
Patch by: Mei Ye

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187764 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-06 02:43:45 +00:00
Matt Arsenault
00d7baad90 Fix missing -*- C++ -*-s
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187758 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-06 00:16:21 +00:00
Peter Collingbourne
acf4cf7757 Introduce an optimisation for special case lists with large numbers of literal entries.
Our internal regex implementation does not cope with large numbers
of anchors very efficiently.  Given a ~3600-entry special case list,
regex compilation can take on the order of seconds.  This patch solves
the problem for the special case of patterns matching literal global
names (i.e. patterns with no regex metacharacters).  Rather than
forming regexes from literal global name patterns, add them to
a StringSet which is checked before matching against the regex.
This reduces regex compilation time by an order of roughly thousands
when reading the aforementioned special case list, according to a
completely unscientific study.

No test cases.  I figure that any new tests for this code should
check that regex metacharacters are properly recognised.  However,
I could not find any documentation which documents the fact that the
syntax of global names in special case lists is based on regexes.
The extent to which regex syntax is supported in special case lists
should probably be decided on/documented before writing tests.

Differential Revision: http://llvm-reviews.chandlerc.com/D1150

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187732 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-05 17:48:04 +00:00
Alexey Samsonov
48d7d1d231 80-cols
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187725 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-05 13:19:49 +00:00
Nadav Rotem
f2855f8886 SLPVectorizer: Fix PR16777. PHInodes may use multiple extracted values that come from different blocks.
Thanks Alexey Samsonov.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187663 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-02 18:40:24 +00:00
Alexey Samsonov
e393b73808 Fix dereferencing end iterator in SimplifyCFG. Patch by Ye Mei.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187646 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-02 08:06:43 +00:00
Matt Arsenault
186f8f9d41 Teach getOrEnforceKnownAlignment about address spaces
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187629 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-01 22:42:18 +00:00
Nadav Rotem
72bc423e7f Move the optlevel check to the frontend.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187628 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-01 22:41:58 +00:00
Nadav Rotem
a4cbd78af8 Only enable SLP-vectorization on O3 builds.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187595 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-01 18:28:15 +00:00
Nadav Rotem
03fb46bed1 80-col
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187535 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-31 22:17:45 +00:00
Owen Anderson
605b3427a9 Preserve fast-math flags when folding (fsub x, (fneg y)) to (fadd x, y).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187462 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-30 23:53:17 +00:00
Matt Arsenault
f34dc428fa Change behavior of calling bitcasted alias functions.
It will now only convert the arguments / return value and call
the underlying function if the types are able to be bitcasted.
This avoids using fp<->int conversions that would occur before.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187444 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-30 20:45:05 +00:00
Nadav Rotem
79c6bee7a9 SLPVectorier: update the debug location for the new instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187363 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-29 18:18:46 +00:00
Chandler Carruth
e1361ec325 Teach the AllocaPromoter which is wrapped around the SSAUpdater
infrastructure to do promotion without a domtree the same smarts about
looking through GEPs, bitcasts, etc., that I just taught mem2reg about.
This way, if SROA chooses to promote an alloca which still has some
noisy instructions this code can cope with them.

I've not used as principled of an approach here for two reasons:
1) This code doesn't really need it as we were already set up to zip
   through the instructions used by the alloca.
2) I view the code here as more of a hack, and hopefully a temporary one.

The SSAUpdater path in SROA is a real sore point for me. It doesn't make
a lot of architectural sense for many reasons:
- We're likely to end up needing the domtree anyways in a subsequent
  pass, so why not compute it earlier and use it.
- In the future we'll likely end up needing the domtree for parts of the
  inliner itself.
- If we need to we could teach the inliner to preserve the domtree. Part
  of the re-work of the pass manager will allow this to be very powerful
  even in large SCCs with many functions.
- Ultimately, computing a domtree has gotten significantly faster since
  the original SSAUpdater-using code went into ScalarRepl. We no longer
  use domfrontiers, and much of domtree is lazily done based on queries
  rather than eagerly.
- At this point keeping the SSAUpdater-based promotion saves a total of
  0.7% on a build of the 'opt' tool for me. That's not a lot of
  performance given the complexity!

So I'm leaving this a bit ugly in the hope that eventually we just
remove all of this nonsense.

I can't even readily test this because this code isn't reachable except
through SROA. When I re-instate the patch that fast-tracks allocas
already suitable for promotion, I'll add a testcase there that failed
before this change. Before that, SROA will fix any test case I give it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187347 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-29 09:06:53 +00:00
Nadav Rotem
3202f6cdb9 Don't vectorize when the attribute NoImplicitFloat is used.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187340 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-29 05:13:00 +00:00
Rafael Espindola
15658b2908 Fix -Wdocumentation warnings.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187336 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-28 23:43:28 +00:00
Chandler Carruth
064a68682d Update comments for SSAUpdater to use the modern doxygen comment
standards for LLVM. Remove duplicated comments on the interface from the
implementation file (implementation comments are left there of course).
Also clean up, re-word, and fix a few typos and errors in the commenst
spotted along the way.

This is in preparation for changes to these files and to keep the
uninteresting tidying in a separate commit.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187335 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-28 22:00:33 +00:00
Chandler Carruth
65f12f1d05 Temporarily revert r187323 until I update SSAUpdater to match mem2reg.
I forgot that we had two totally independent things here. :: sigh ::

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187327 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-28 09:05:49 +00:00
Chandler Carruth
cea60aff34 Now that mem2reg understands how to cope with a slightly wider set of
uses of an alloca, we can pre-compute promotability while analyzing an
alloca for splitting in SROA. That lets us short-circuit the common case
of a bunch of trivially promotable allocas. This cuts 20% to 30% off the
run time of SROA for typical frontend-generated IR sequneces I'm seeing.
It gets the new SROA to within 20% of ScalarRepl for such code. My
current benchmark for these numbers is PR15412, but it fits the general
pattern of IR emitted by Clang so it should be widely applicable.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187323 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-28 08:27:12 +00:00
Chandler Carruth
6c3a95dab5 Thread DataLayout through the callers and into mem2reg. This will be
useful in a subsequent patch, but causes an unfortunate amount of noise,
so I pulled it out into a separate patch.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187322 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-28 06:43:11 +00:00
Nadav Rotem
1aaaf34154 Update the comment
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187316 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-27 23:28:47 +00:00
Chandler Carruth
89934cbd34 Don't use all the #ifdefs to hide the stats counters and instead rely on
their being optimized out in debug mode. Realistically, this just isn't
going to be the slow part anyways. This also fixes unused variable
warnings that are breaking LLD build bots. =/ I didn't see these at
first, and kept losing track of the fact that they were broken.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187297 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-27 10:17:49 +00:00
Chandler Carruth
33ae899113 Merge the removal of dead instructions and lifetime markers with the
analysis of the alloca. We don't need to visit all the users twice for
this. We build up a kill list during the analysis and then just process
it afterward. This recovers the tiny bit of performance lost by moving
to the visitor based analysis system as it removes one entire use-list
walk from mem2reg. In some cases, this is now faster than mem2reg was
previously.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187296 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-27 09:43:30 +00:00
Nick Lewycky
81e480463d Reimplement isPotentiallyReachable to make nocapture deduction much stronger.
Adds unit tests for it too.

Split BasicBlockUtils into an analysis-half and a transforms-half, and put the
analysis bits into a new Analysis/CFG.{h,cpp}. Promote isPotentiallyReachable
into llvm::isPotentiallyReachable and move it into Analysis/CFG.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187283 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-27 01:24:00 +00:00
Tom Stellard
57e6b2d1f3 SimplifyCFG: Use parallel-and and parallel-or mode to consolidate branch conditions
Merge consecutive if-regions if they contain identical statements.
Both transformations reduce number of branches.  The transformation
is guarded by a target-hook, and is currently enabled only for +R600,
but the correctness has been tested on X86 target using a variety of
CPU benchmarks.

Patch by: Mei Ye

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187278 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-27 00:01:07 +00:00
Nadav Rotem
67a38a2875 SLP Vectorier: Don't vectorize really short chains because they are already handled by the SelectionDAG store-vectorizer, which does a better job in deciding when to vectorize.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187267 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-26 23:07:55 +00:00
Nadav Rotem
a629c3a4f0 SLP Vectorizer: Disable the vectorization of non power of two chains, such as <3 x float>, because we dont have a good cost model for these types.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187265 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-26 22:53:11 +00:00
Owen Anderson
107c578126 Fix variable name.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187253 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-26 22:06:21 +00:00
Owen Anderson
0c326f07ca When InstCombine tries to fold away (fsub x, (fneg y)) into (fadd x, y), it is
also worthwhile for it to look through FP extensions and truncations, whose
application commutes with fneg.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187249 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-26 21:40:29 +00:00