Commit Graph

4702 Commits

Author SHA1 Message Date
Kostya Serebryany
42a9da35b8 Don't speculate loads under ThreadSanitizer
Summary:
Don't speculate loads under ThreadSanitizer.
This fixes https://code.google.com/p/thread-sanitizer/issues/detail?id=40
Also discussed here: http://lists.cs.uiuc.edu/pipermail/llvmdev/2013-November/067929.html

Reviewers: chandlerc

Reviewed By: chandlerc

CC: llvm-commits, dvyukov

Differential Revision: http://llvm-reviews.chandlerc.com/D2227

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195324 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-21 07:29:28 +00:00
Paul Robinson
fe45fd084d The 'optnone' attribute means don't inline anything into this function
(except functions marked always_inline).
Functions with 'optnone' must also have 'noinline' so they don't get
inlined into any other function.

Based on work by Andrea Di Biagio.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195046 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-18 21:44:03 +00:00
Benjamin Kramer
b69143c6a9 Annotate APInt methods where it's not clear whether they are in place with warn_unused_result.
Fix ScalarEvolution bugs uncovered by this.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194928 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-16 16:25:41 +00:00
Matt Arsenault
74c996cbd1 Use correct size for address space in BasicAA.
The tests just hit this with a different sized
address space since I haven't figured out how
to use this to break it.

I thought I committed this a long time ago,
and I'm not sure why missing this hasn't caused
any problems.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194903 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-16 00:36:43 +00:00
Matt Arsenault
59d3ae6cdc Add addrspacecast instruction.
Patch by Michele Scandale!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194760 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-15 01:34:59 +00:00
Michael Gottesman
e2058ff5bd Added BlockFrequencyInfo::view for displaying the block frequency propagation graph via graphviz.
This is useful for debugging issues in the BlockFrequency implementation since
one can easily visualize where probability mass and other errors occur in the
propagation.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194654 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-14 02:27:46 +00:00
Yunzhong Gao
2999b2f2cc Fixing a heisenbug where the memory dependence analysis behaves differently
with and without -g.

Adding a test case to make sure that the threshold used in the memory
dependence analysis is respected. The test case also checks that debug
intrinsics are not counted towards this threshold.

Differential Revision: http://llvm-reviews.chandlerc.com/D2141



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194646 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-14 01:10:52 +00:00
Michael Gottesman
006806267a Fixed 80+ violations.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194634 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-14 00:05:07 +00:00
Sebastian Pop
f44941d81d add more comments around the delinearization of arrays
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194612 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-13 22:37:58 +00:00
Jakub Staszak
dc9a217d05 Simplify code. No functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194602 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-13 20:18:38 +00:00
Benjamin Kramer
1a362619f8 Move Delinearization pass into an anonymous namespace.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194582 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-13 15:35:17 +00:00
Sebastian Pop
5230ad61fd delinearization of arrays
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194527 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-12 22:47:20 +00:00
Wan Xiaofei
3cda2d3885 Change data structure to memorize computed result in ScalarEvolution
Replace std::map with SmallVector to memorize the cached result since SCEV usually belongs to little Loop/BB
Linear scan on SmallVector is faster than std::map.

Code reviewer : Andrew Trick.
Test result   : Pass Unit Test & LLVM Test Suite

401.bzip2	0.425721	0.419981	101.37%
403.gcc		24.53855	24.2667		101.12%
429.mcf		0.060847	0.059944	101.51%
433.milc	0.646009	0.636119	101.55%
444.namd	1.383928	1.370614	100.97%
445.gobmk	5.836575	5.800225	100.63%
450.soplex	1.911257	1.895963	100.81%
456.hmmer	1.039565	1.032534	100.68%
458.sjeng	0.897401	0.885567	101.34%
464.h264ref	3.645908	3.577991	101.90%
470.lbm		0.049456	0.048398	102.19%
471.omnetpp	5.638575	5.60435		100.61%
bitmnp01	0.045738	0.045291	100.99%
cjpegv2data	0.304359	0.302833	100.50%
idctrn01	0.046433	0.045763	101.46%
quake2		4.534416	4.4952		100.87%
quake		2.688566	2.659208	101.10%
xcsoar		12.42545	12.30385	100.99%
linpack		0.038739	0.03803		101.86%
matrix01	0.053564	0.0528		101.45%
nbench		0.402867	0.395803	101.78%
tblook01	0.021265	0.021015	101.19%
ttsprk01	0.066384	0.065566	101.25%

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194459 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-12 09:40:41 +00:00
Matt Arsenault
20f1fe5c50 Use size function instead of manually calculating it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194345 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-10 03:18:50 +00:00
Chandler Carruth
49837ef811 Move the old pass manager infrastructure into a legacy namespace and
give the files a legacy prefix in the right directory. Use forwarding
headers in the old locations to paper over the name change for most
clients during the transitional period.

No functionality changed here! This is just clearing some space to
reduce renaming churn later on with a new system.

Even when the new stuff starts to go in, it is going to be hidden behind
a flag and off-by-default as it is still WIP and under development.

This patch is specifically designed so that very little out-of-tree code
has to change. I'm going to work as hard as I can to keep that the case.
Only direct forward declarations of the PassManager class are impacted
by this change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194324 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-09 12:26:54 +00:00
Andrew Trick
10bb82e54f Rewrite SCEV's backedge taken count computation.
Patch by Michele Scandale!

Rewrite of the functions used to compute the backedge taken count of a
loop on LT and GT comparisons.

I decided to split the handling of LT and GT cases becasue the trick
"a > b == -a < -b" in some cases prevents the trip count computation
due to the multiplication by -1 on the two operands of the
comparison. This issue comes from the conservative computation of
value range of SCEVs: taking the negative SCEV of an expression that
have a small positive range (e.g. [0,31]), we would have a SCEV with a
fullset as value range.

Indeed, in the new rewritten function I tried to better handle the
maximum backedge taken count computation when MAX/MIN expression are
used to handle the cases where no entry guard is found.

Some test have been modified in order to check the new value correctly
(I manually check them and reasoning on possible overflow the new
values seem correct).

I finally added a new test case related to the multiplication by -1
issue on GT comparisons.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194116 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-06 02:08:26 +00:00
Matt Arsenault
896a885f21 Fix another constant folding address space place I missed.
This fixes an assertion failure with a different sized address space.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194014 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-04 20:46:52 +00:00
Hal Finkel
e14fb07357 Consider (x == -1) unlikely in BranchProbabilityInfo
This adds another heuristic to BPI, similar to the existing heuristic that
considers (x == 0) unlikely to be true. As suggested in the PACT'98 paper by
Deitrich, Cheng, and Hwu, -1 is often used to indicate an invalid index, and
equality comparisons with -1 are also unlikely to succeed. Local
experimentation supports this hypothesis: This yields a 1-2% speedup in the
test-suite sqlite benchmark on the PPC A2 core, with no significant
regressions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193855 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-01 10:58:22 +00:00
Rafael Espindola
c143c7573b Merge CallGraph and BasicCallGraph.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193734 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-31 03:03:55 +00:00
Benjamin Kramer
19ea37059a SCEV: Make the final add of an inbounds GEP nuw if we know that the index is positive.
We can't do this for the general case as saying a GEP with a negative index
doesn't have unsigned wrap isn't valid for negative indices.
  %gep = getelementptr inbounds i32* %p, i64 -1

But an inbounds GEP cannot run past the end of address space. So we check for
the very common case of a positive index and make GEPs derived from that NUW.
Together with Andy's recent non-unit stride work this lets us analyze loops
like

  void foo3(int *a, int *b) {
    for (; a < b; a++) {}
  }

PR12375, PR12376.

Differential Revision: http://llvm-reviews.chandlerc.com/D2033

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193514 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-28 07:30:06 +00:00
Shuxin Yang
69bd41dfe3 Revert r193251 : Use address-taken to disambiguate global variable and indirect memops.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193489 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-27 03:08:44 +00:00
Wan Xiaofei
887f9c5ec1 Quick look-up for block in loop.
This patch implements quick look-up for block in loop by maintaining a hash set for blocks.
It improves the efficiency of loop analysis a lot, the biggest improvement could be 5-6%(458.sjeng).
Below are the compilation time for our benchmark in llc before & after the patch.

Benchmark	llc - trunk		llc - patched	
401.bzip2	0.339081	100.00%	0.329657	102.86%
403.gcc		19.853966	100.00%	19.605466	101.27%
429.mcf		0.049823	100.00%	0.048451	102.83%
433.milc	0.514898	100.00%	0.510217	100.92%
444.namd	1.109328	100.00%	1.103481	100.53%
445.gobmk	4.988028	100.00%	4.929114	101.20%
456.hmmer	0.843871	100.00%	0.825865	102.18%
458.sjeng	0.754238	100.00%	0.714095	105.62%
464.h264ref	2.9668		100.00%	2.90612		102.09%
471.omnetpp	4.556533	100.00%	4.511886	100.99%
bitmnp01	0.038168	100.00%	0.0357		106.91%
idctrn01	0.037745	100.00%	0.037332	101.11%
libquake2	3.78689		100.00%	3.76209		100.66%
libquake_	2.251525	100.00%	2.234104	100.78%
linpack		0.033159	100.00%	0.032788	101.13%
matrix01	0.045319	100.00%	0.043497	104.19%
nbench		0.333161	100.00%	0.329799	101.02%
tblook01	0.017863	100.00%	0.017666	101.12%
ttsprk01	0.054337	100.00%	0.053057	102.41%

Reviewer	: Andrew Trick <atrick@apple.com>, Hal Finkel <hfinkel@anl.gov>
Approver	: Andrew Trick <atrick@apple.com>
Test		: Pass make check-all & llvm test-suite


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193460 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-26 03:08:02 +00:00
Andrew Trick
4d4bbaf997 Fix SCEVExpander: don't try to expand quadratic recurrences outside a loop.
Partial fix for PR17459: wrong code at -O3 on x86_64-linux-gnu
(affecting trunk and 3.3)

When SCEV expands a recurrence outside of a loop it attempts to scale
by the stride of the recurrence. Chained recurrences don't work that
way. We could compute binomial coefficients, but would hve to
guarantee that the chained AddRec's are in a perfectly reduced form.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193438 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-25 21:35:56 +00:00
Andrew Trick
8aa8cea3e9 Fix LSR: don't normalize quadratic recurrences.
Partial fix for PR17459: wrong code at -O3 on x86_64-linux-gnu
(affecting trunk and 3.3)

ScalarEvolutionNormalization was attempting to normalize by adding and
subtracting strides. Chained recurrences don't work that way.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193437 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-25 21:35:52 +00:00
Rafael Espindola
6e1c511aba Call destroy from ~BasicCallGraph.
This fix a memory leak found by valgrind.

Calling it from the base class destructor would not destroy the BasicCallGraph
bits.

FIXME: BasicCallGraph is the only thing that inherits from CallGraph. Can
we merge the two?

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193412 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-25 15:01:34 +00:00
Nuno Lopes
5e1d0d39db fix PR17635: false positive with packed structures
LLVM optimizers may widen accesses to packed structures that overflow the structure itself, but should be in bounds up to the alignment of the object

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193317 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-24 09:17:24 +00:00
Shuxin Yang
8e3851a6eb Use address-taken to disambiguate global variable and indirect memops.
Major steps include:
 1). introduces a not-addr-taken bit-field in GlobalVariable
 2). GlobalOpt pass sets "not-address-taken" if it proves a global varirable 
    dosen't have its address taken.
 3). AA use this info for disambiguation. 


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193251 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-23 17:28:19 +00:00
Andrew Trick
78fe4d62fb Clarify SCEV comments.
We handle for(i=n; i>0; i -= s) by canonicalizing within SCEV to for(i=-n; i<0; i += s).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193147 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-22 05:09:40 +00:00
Manman Ren
11d78777d5 TBAA: fix PR17620.
We can have a struct type with a single field and the field does not start
with 0. In that case, we should correctly update the offset.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193137 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-22 01:40:25 +00:00
Matt Arsenault
244d245974 Use more type helper functions
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193109 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-21 19:43:56 +00:00
Matt Arsenault
4784bb6f44 Fix creating bitcasts between address spaces in SCEV.
The test before wasn't successfully testing this
since it was missing the datalayout piece to change
the size of the second address space.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193102 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-21 18:41:10 +00:00
Matt Arsenault
325ee6e115 Remove unused SCEV functions
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193097 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-21 18:08:09 +00:00
Andrew Trick
a5c5bc9948 SCEV should use NSW to get trip count for positive nonunit stride loops.
SCEV currently fails to compute loop counts for nonunit stride
loops. This comes up frequently. It prevents loop optimization and
forces vectorization to insert extra loop checks.

For example:
void foo(int n, int *x) {
 for (int i = 0; i < n; i += 3) {
   x[i] = i;
   x[i+1] = i+1;
   x[i+2] = i+2;
 }
}

We need to properly handle the case in which limit > INT_MAX-stride. In
the above case: n > INT_MAX-3. In this case the loop counter will step
beyond the limit and overflow at the same time. However, knowing that
signed integer overlow in undefined, we can assume the loop test
behavior is arbitrary after overflow. This obeys both C undefined
behavior rules, and the more strict LLVM poison value rules.

I'm finally fixing this in response to Hal Finkel's persistence.
The most probable reason that we never optimized this before is that
we were being careful to handle case where the developer expected a
side-effect free infinite loop relying on overflow:

for (int i = 0; i < n; i += s) {
  ++j;
}
return j;

If INT_MAX+1 is a multiple of s and n > INT_MAX-s, then we might
expect an infinite loop. However there are plenty of ways to achieve
this effect without relying on undefined behavior of signed overflow.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193015 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-18 23:43:53 +00:00
Craig Topper
390ff499f0 Remove x86_sse42_crc32_64_8 intrinsic. It has no functional difference from x86_sse42_crc32_32_8 and was not mapped to a clang builtin. I'm not even sure why this form of the instruction is even called out explicitly in the docs. Also add AutoUpgrade support to convert it into the other intrinsic with appropriate trunc and zext.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192672 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-15 05:20:47 +00:00
Matt Arsenault
cee51c4803 Rename DataLayout variables TD -> DL
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191927 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-03 19:50:01 +00:00
Benjamin Kramer
4d63c8daec CaptureTracking: Plug a loophole in the "too many uses" heuristic.
The heuristic was added to avoid spending too much compile time A specially
crafted test case (PR17461, PR16474) with many uses on a select or bitcast
instruction can still trigger the slow case. Add a check for that case.

This only affects compile time, don't have a good way to test it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191896 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-03 13:24:02 +00:00
Chandler Carruth
dd5d86d992 Remove the very substantial, largely unmaintained legacy PGO
infrastructure.

This was essentially work toward PGO based on a design that had several
flaws, partially dating from a time when LLVM had a different
architecture, and with an effort to modernize it abandoned without being
completed. Since then, it has bitrotted for several years further. The
result is nearly unusable, and isn't helping any of the modern PGO
efforts. Instead, it is getting in the way, adding confusion about PGO
in LLVM and distracting everyone with maintenance on essentially dead
code. Removing it paves the way for modern efforts around PGO.

Among other effects, this removes the last of the runtime libraries from
LLVM. Those are being developed in the separate 'compiler-rt' project
now, with somewhat different licensing specifically more approriate for
runtimes.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191835 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-02 15:42:23 +00:00
Rafael Espindola
8819c84aed Remove several unused variables.
Patch by Alp Toker.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191757 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-01 13:32:03 +00:00
Benjamin Kramer
341562b9fb SCEVExpander: Fix a regression I introduced by to eagerly adding RAII objects.
PR17425.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191741 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-01 12:17:11 +00:00
Benjamin Kramer
d427882166 Convert manual insert point restores to the new RAII object.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191675 91177308-0d34-0410-b5e6-96231b3b80d8
2013-09-30 15:40:17 +00:00
Benjamin Kramer
2f08433210 ObjectSizeOffsetEvaluator: Don't run into infinite recursion if we have a cyclic GEP.
Those can occur in dead code. PR17402.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191644 91177308-0d34-0410-b5e6-96231b3b80d8
2013-09-29 19:39:13 +00:00
Manman Ren
e5f32cf320 TBAA: try to fix the dragonegg bots.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191585 91177308-0d34-0410-b5e6-96231b3b80d8
2013-09-27 22:59:21 +00:00
Matt Arsenault
9ed1a3cddb Minor code simplification
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191579 91177308-0d34-0410-b5e6-96231b3b80d8
2013-09-27 22:38:23 +00:00
Matt Arsenault
b060a46b0d Use type helper functions
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191574 91177308-0d34-0410-b5e6-96231b3b80d8
2013-09-27 22:18:51 +00:00
Manman Ren
9e81c3bdb2 TBAA: handle scalar TBAA format and struct-path aware TBAA format.
Remove the command line argument "struct-path-tbaa" since we should not depend
on command line argument to decide which format the IR file is using. Instead,
we check the first operand of the tbaa tag node, if it is a MDNode, we treat
it as struct-path aware TBAA format, otherwise, we treat it as scalar TBAA
format.

When clang starts to use struct-path aware TBAA format no matter whether
struct-path-tbaa is no, and we can auto-upgrade existing bc files, the support
for scalar TBAA format can be dropped.

Existing testing cases are updated to use the struct-path aware TBAA format.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191538 91177308-0d34-0410-b5e6-96231b3b80d8
2013-09-27 18:34:27 +00:00
Benjamin Kramer
09b16f3bb5 MemoryBuiltins: Remove posix_memalign from the list and replace it with a TODO.
This code isn't ready to deal with allocation functions where the return is not
the allocated pointer. The checks below will reject posix_memalign anyways.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191319 91177308-0d34-0410-b5e6-96231b3b80d8
2013-09-24 17:49:08 +00:00
Benjamin Kramer
d44f9f2ff8 MemoryBuiltins: Reinstate optimizing (uninitialized) loads from operator new.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191315 91177308-0d34-0410-b5e6-96231b3b80d8
2013-09-24 17:34:29 +00:00
Benjamin Kramer
989779ccc7 MemoryBuiltins: Fix operator new bits.
We really don't want to optimize malloc return value checks away.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191313 91177308-0d34-0410-b5e6-96231b3b80d8
2013-09-24 17:15:14 +00:00
Benjamin Kramer
6629210aaf Teach MemoryBuiltins and InstructionSimplify that operator new never returns NULL.
This is safe per C++11 18.6.1.1p3: [operator new returns] a non-null pointer to
suitably aligned storage (3.7.4), or else throw a bad_alloc exception. This
requirement is binding on a replacement version of this function.

Brings us a tiny bit closer to eliminating more vector push_backs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191310 91177308-0d34-0410-b5e6-96231b3b80d8
2013-09-24 16:37:51 +00:00
Benjamin Kramer
baca5334db InstSimplify: Fold equality comparisons between non-inbounds GEPs.
Overflow doesn't affect the correctness of equalities. Computing this is cheap,
we just reuse the computation for the inbounds case and try to peel of more
non-inbounds GEPs. This pattern is unlikely to ever appear in code generated by
Clang, but SCEV occasionally produces it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191200 91177308-0d34-0410-b5e6-96231b3b80d8
2013-09-23 14:16:38 +00:00