Commit Graph

6236 Commits

Author SHA1 Message Date
Rong Xu d0dfb67fe1 [PGO] Revert r260146 as it breaks Darwin platforms.
r260146 | xur | 2016-02-08 13:07:46 -0800 (Mon, 08 Feb 2016) | 13 lines
[PGO] Differentiate Clang instrumentation and IR level instrumentation profiles

llvm-svn: 260170
2016-02-08 23:11:16 +00:00
Rong Xu 1288a19421 [PGO] Differentiate Clang instrumentation and IR level instrumentation profiles
This patch uses one bit in profile version to differentiate Clang
instrumentation and IR level instrumentation profiles.

PGOInstrumenation generates a COMDAT variable __llvm_profile_raw_version so
that the compiler runtime can set the right profile kind.
PGOInstrumenation now checks this bit to make sure it's an IR level
instrumentation profile.

Differential Revision: http://reviews.llvm.org/D15540

llvm-svn: 260146
2016-02-08 21:07:46 +00:00
Silviu Baranga ea63a7f512 [SCEV][LAA] Re-commit r260085 and r260086, this time with a fix for the memory
sanitizer issue. The PredicatedScalarEvolution's copy constructor
wasn't copying the Generation value, and was leaving it un-initialized.

Original commit message:

[SCEV][LAA] Add no wrap SCEV predicates and use use them to improve strided pointer detection

Summary:
This change adds no wrap SCEV predicates with:
  - support for runtime checking
  - support for expression rewriting:
      (sext ({x,+,y}) -> {sext(x),+,sext(y)}
      (zext ({x,+,y}) -> {zext(x),+,sext(y)}

Note that we are sign extending the increment of the SCEV, even for
the zext case. This is needed to cover the fairly common case where y would
be a (small) negative integer. In order to do this, this change adds two new
flags: nusw and nssw that are applicable to AddRecExprs and permit the
transformations above.

We also change isStridedPtr in LAA to be able to make use of
these predicates. With this feature we should now always be able to
work around overflow issues in the dependence analysis.

Reviewers: mzolotukhin, sanjoy, anemet

Subscribers: mzolotukhin, sanjoy, llvm-commits, rengolin, jmolloy, hfinkel

Differential Revision: http://reviews.llvm.org/D15412

llvm-svn: 260112
2016-02-08 17:02:45 +00:00
Silviu Baranga 41b4973329 Revert r260086 and r260085. They have broken the memory
sanitizer bots.

llvm-svn: 260087
2016-02-08 11:56:15 +00:00
Silviu Baranga a35fadc7c4 [SCEV][LAA] Add no wrap SCEV predicates and use use them to improve strided pointer detection
Summary:
This change adds no wrap SCEV predicates with:
  - support for runtime checking
  - support for expression rewriting:
      (sext ({x,+,y}) -> {sext(x),+,sext(y)}
      (zext ({x,+,y}) -> {zext(x),+,sext(y)}

Note that we are sign extending the increment of the SCEV, even for
the zext case. This is needed to cover the fairly common case where y would
be a (small) negative integer. In order to do this, this change adds two new
flags: nusw and nssw that are applicable to AddRecExprs and permit the
transformations above.

We also change isStridedPtr in LAA to be able to make use of
these predicates. With this feature we should now always be able to
work around overflow issues in the dependence analysis.

Reviewers: mzolotukhin, sanjoy, anemet

Subscribers: mzolotukhin, sanjoy, llvm-commits, rengolin, jmolloy, hfinkel

Differential Revision: http://reviews.llvm.org/D15412

llvm-svn: 260085
2016-02-08 10:45:50 +00:00
Daniel Berlin e19fa17016 Make check line consistent
llvm-svn: 260055
2016-02-07 20:57:46 +00:00
Ashutosh Nema 3bc6d46e62 Corrected tests for Loop Versioning LICM, by adding “REQUIRES: asserts”.
Earlier they were failing under no-assert build.

llvm-svn: 259989
2016-02-06 12:34:41 +00:00
Ashutosh Nema df6763abe8 New Loop Versioning LICM Pass
Summary:
When alias analysis is uncertain about the aliasing between any two accesses,
it will return MayAlias. This uncertainty from alias analysis restricts LICM
from proceeding further. In cases where alias analysis is uncertain we might
use loop versioning as an alternative.

Loop Versioning will create a version of the loop with aggressive aliasing
assumptions in addition to the original with conservative (default) aliasing
assumptions. The version of the loop making aggressive aliasing assumptions
will have all the memory accesses marked as no-alias. These two versions of
loop will be preceded by a memory runtime check. This runtime check consists
of bound checks for all unique memory accessed in loop, and it ensures the
lack of memory aliasing. The result of the runtime check determines which of
the loop versions is executed: If the runtime check detects any memory
aliasing, then the original loop is executed. Otherwise, the version with
aggressive aliasing assumptions is used.

The pass is off by default and can be enabled with command line option 
-enable-loop-versioning-licm.

Reviewers: hfinkel, anemet, chatur01, reames

Subscribers: MatzeB, grosser, joker.eph, sanjoy, javed.absar, sbaranga,
             llvm-commits

Differential Revision: http://reviews.llvm.org/D9151

llvm-svn: 259986
2016-02-06 07:47:48 +00:00
Adam Nemet 9455c1d2b1 [LoopLoadElim] Don't allow versioning when optForSize
This was requested in the review of D16300.

llvm-svn: 259861
2016-02-05 01:14:05 +00:00
Adam Nemet 0cf866ac6c Fix typo in comment
llvm-svn: 259860
2016-02-05 01:14:00 +00:00
George Burgess IV 43d8365ecb Add a test for MemorySSA. NFC.
We don't currently have many tests that deal with operations on multiple
local MemoryLocations. This new test helps out a bit in that regard.

llvm-svn: 259854
2016-02-05 00:42:02 +00:00
Benjamin Kramer e4dff62f64 The canonical way to XFAIL a test for all targets is XFAIL: *, not XFAIL:
Fix the lit bug that enabled this "feature" (empty triple is substring
of all possible target triples) and change the two outliers to use the
documented * syntax.

llvm-svn: 259799
2016-02-04 16:21:38 +00:00
Wei Mi a49559befb [SCEV] Try to reuse existing value during SCEV expansion
Current SCEV expansion will expand SCEV as a sequence of operations
and doesn't utilize the value already existed. This will introduce
redundent computation which may not be cleaned up throughly by
following optimizations.

This patch introduces an ExprValueMap which is a map from SCEV to the
set of equal values with the same SCEV. When a SCEV is expanded, the
set of values is checked and reused whenever possible before generating
a sequence of operations.

The original commit triggered regressions in Polly tests. The regressions
exposed two problems which have been fixed in current version.

1. Polly will generate a new function based on the old one. To generate an
instruction for the new function, it builds SCEV for the old instruction,
applies some tranformation on the SCEV generated, then expands the transformed
SCEV and insert the expanded value into new function. Because SCEV expansion
may reuse value cached in ExprValueMap, the value in old function may be
inserted into new function, which is wrong.
   In SCEVExpander::expand, there is a logic to check the cached value to
be used should dominate the insertion point. However, for the above
case, the check always passes. That is because the insertion point is
in a new function, which is unreachable from the old function. However
for unreachable node, DominatorTreeBase::dominates thinks it will be
dominated by any other node.
   The fix is to simply add a check that the cached value to be used in
expansion should be in the same function as the insertion point instruction.

2. When the SCEV is of scConstant type, expanding it directly is cheaper than
reusing a normal value cached. Although in the cached value set in ExprValueMap,
there is a Constant type value, but it is not easy to find it out -- the cached
Value set is not sorted according to the potential cost. Existing reuse logic
in SCEVExpander::expand simply chooses the first legal element from the cached
value set.
   The fix is that when the SCEV is of scConstant type, don't try the reuse
logic. simply expand it.

Differential Revision: http://reviews.llvm.org/D12090

llvm-svn: 259736
2016-02-04 01:27:38 +00:00
Gerolf Hoflehner 2432bd0ddd [SimplifyCFG] Fix for "endless" loop after dead code removal (Alternative to
D16251)

Summary:
This is a simpler fix to the problem than the dominator approach in
http://reviews.llvm.org/D16251. It adds only values into the gather() while loop
that have been seen before.

The actual endless loop is in the constant compare gather() routine in
Utils/SimplifyCFG.cpp. The same value ret.0.off0.i is pushed back into the
queue:
%.ret.0.off0.i = or i1 %.ret.0.off0.i, %cmp10.i

Here is what happens at the IR level:

for.cond.i:                                       ; preds = %if.end6.i,
%if.end.i54
%ix.0.i = phi i32 [ 0, %if.end.i54 ], [ %inc.i55, %if.end6.i ]
%ret.0.off0.i = phi i1 [false, %if.end.i54], [%.ret.0.off0.i, %if.end6.i] <<<
%cmp2.i = icmp ult i32 %ix.0.i, %11
br i1 %cmp2.i, label %for.body.i, label %LBJ_TmpSimpleNeedExt.exit

if.end6.i:                                        ; preds = %for.body.i
%cmp10.i = icmp ugt i32 %conv.i, %add9.i
%.ret.0.off0.i = or i1 %ret.0.off0.i, %cmp10.i <<<

When if.end.i54 gets eliminated which removes the definition of ret.0.off0.i.
The result is the expression %.ret.0.off0.i = or i1 %.ret.0.off0.i, %cmp10.i
(Note the first ‘or’ operand is now %.ret.0.off0.i, and *NOT* %ret.0.off0.i).
And
now there is use of .ret.0.off0.i before a definition which triggers the
“endless” loop in gather():

while(!DFT.empty()) {

    V = DFT.pop_back_val();   // V is .ret.0.off0.i

    if (Instruction *I = dyn_cast<Instruction>(V)) {
      // If it is a || (or && depending on isEQ), process the operands.
      if (I->getOpcode() == (isEQ ? Instruction::Or : Instruction::And)) {
        DFT.push_back(I->getOperand(1));  // This is now .ret.0.off0.i also
        DFT.push_back(I->getOperand(0));

        continue; // “endless loop” for .ret.0.off0.i
      }

Reviewers: reames, ahatanak

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D16839

llvm-svn: 259730
2016-02-03 23:54:25 +00:00
David Majnemer a53b5bbb18 [LoopStrengthReduce] Don't rewrite PHIs with incoming values from CatchSwitches
Bail out if we have a PHI on an EHPad that gets a value from a
CatchSwitchInst.  Because the CatchSwitchInst cannot be split, there is
no good place to stick any instructions.

This fixes PR26373.

llvm-svn: 259702
2016-02-03 21:30:34 +00:00
Wei Mi 97de385868 Revert r259662, which caused regressions on polly tests.
llvm-svn: 259675
2016-02-03 18:05:57 +00:00
Quentin Colombet 7ec03dc7f8 [InstCombine] Revert r238452: Fold IntToPtr and PtrToInt into preceding loads.
According to git bisect, this is the root cause of a miscompile for Regex in
libLLVMSupport. I am still working on reducing a test case.
The actual bug may be elsewhere and this commit just exposed it.

Anyway, at the moment, to reproduce, follow these steps:
1. Build clang and libLTO in release mode.
2. Create a new build directory <stage2> and cd into it.
3. Use clang and libLTO from #1 to build llvm-extract in Release mode + asserts
   using -O2 -flto
4. Run llvm-extract  -ralias '.*bar' -S test/Other/extract-alias.ll

Result:
program doesn't contain global named '.*bar'!

Expected result:
@a0a0bar = alias void ()* @bar
@a0bar = alias void ()* @bar

declare void @bar()

Note: In step #3, if you don't use lto or asserts, the miscompile disappears.
llvm-svn: 259674
2016-02-03 18:04:13 +00:00
Wei Mi ed133978a0 [SCEV] Try to reuse existing value during SCEV expansion
Current SCEV expansion will expand SCEV as a sequence of operations
and doesn't utilize the value already existed. This will introduce
redundent computation which may not be cleaned up throughly by
following optimizations.

This patch introduces an ExprValueMap which is a map from SCEV to the
set of equal values with the same SCEV. When a SCEV is expanded, the
set of values is checked and reused whenever possible before generating
a sequence of operations.

Differential Revision: http://reviews.llvm.org/D12090

llvm-svn: 259662
2016-02-03 17:05:12 +00:00
James Molloy 6e518a3b50 [DemandedBits] Revert r249687 due to PR26071
This regresses a test in LoopVectorize, so I'll need to go away and think about how to solve this in a way that isn't broken.

From the writeup in PR26071:

What's happening is that ComputeKnownZeroes is telling us that all bits except the LSB are zero. We're then deciding that only the LSB needs to be demanded from the icmp's inputs.

This is where we're wrong - we're assuming that after simplification the bits that were known zero will continue to be known zero. But they're not - during trivialization the upper bits get changed (because an XOR isn't shrunk), so the icmp fails.

The fault is in demandedbits - its contract does clearly state that a non-demanded bit may either be zero or one.

llvm-svn: 259649
2016-02-03 15:05:06 +00:00
Adam Nemet d52ed84160 [LoopVersioning] Expose loop versioning as a pass too
Summary:
LoopVersioning is a transform utility that transform passes can use to
run-time disambiguate may-aliasing accesses. I'd like to also expose as
pass to allow it to be unit-tested.

I am planning to add support for non-aliasing annotation in
LoopVersioning and I'd like to be able to write tests directly using
this pass.

(After that feature is done, the pass could also be used to look for
optimization opportunities that are hidden behind incomplete alias
information at compile time.)

The pass drives LoopVersioning in its default way which is to fully
disambiguate may-aliasing accesses no matter how many checks are
required.

Reviewers: hfinkel, ashutosh.nema, sbaranga

Subscribers: zzheng, mssimpso, llvm-commits, sanjoy

Differential Revision: http://reviews.llvm.org/D16612

llvm-svn: 259610
2016-02-03 00:06:10 +00:00
George Burgess IV e1100f533f This patch adds MemorySSA to LLVM.
Please see include/llvm/Transforms/Utils/MemorySSA.h for a description
of MemorySSA, and what it does.

Differential Revision: http://reviews.llvm.org/D7864

llvm-svn: 259595
2016-02-02 22:46:49 +00:00
Philip Reames 44456b8963 [LVI] Introduce an intersect operation on lattice values
LVI has several separate sources of facts - edge local conditions, recursive queries, assumes, and control independent value facts - which all apply to the same value at the same location. The existing implementation was very conservative about exploiting all of these facts at once.

This change introduces an "intersect" function specifically to abstract the action of picking a good set of facts from all of the separate facts given. At the moment, this function is relatively simple (i.e. mostly just reuses the bits which were already there), but even the minor additions reveal the inherent power. For example, JumpThreading is now capable of doing an inductive proof that a particular value is always positive and removing a half range check.

I'm currently only using the new intersect function in one place. If folks are happy with the direction of the work, I plan on making a series of small changes without review to replace mergeIn with intersect at all the appropriate places.

Differential Revision: http://reviews.llvm.org/D14476

llvm-svn: 259461
2016-02-02 03:15:40 +00:00
Anna Zaks cad7994c3b [safestack] Make sure the unsafe stack pointer is popped in all cases
The unsafe stack pointer is only popped in moveStaticAllocasToUnsafeStack so it won't happen if there are no static allocas.

Fixes https://llvm.org/bugs/show_bug.cgi?id=26122

Differential Revision: http://reviews.llvm.org/D16339

llvm-svn: 259447
2016-02-02 01:03:11 +00:00
Philip Reames f3b94694c0 [LVI] Missing test case from 259432
llvm-svn: 259437
2016-02-01 23:44:38 +00:00
Philip Reames c0bdb0c1e5 [LVI] Add select handling
Teach LVI to handle select instructions in the exact same way it handles PHI nodes.  This is useful since various parts of the optimizer convert PHI nodes into selects and we don't want these transformations to cause inferior optimization.  

Note that this patch does nothing to exploit the implied constraint on the inputs represented by the select condition itself.  That will be a later patch and is blocked on http://reviews.llvm.org/D14476

llvm-svn: 259429
2016-02-01 22:57:53 +00:00
Sanjay Patel 103ab7d571 [InstCombine] simplify masked scatter/gather intrinsics with zero masks
A masked scatter with a zero mask means there's no store.
A masked gather with a zero mask means the passthru arg is returned.

This is a continuation of:
http://reviews.llvm.org/rL259369
http://reviews.llvm.org/rL259392

llvm-svn: 259421
2016-02-01 22:10:26 +00:00
Jun Bum Lim 53907161cc Avoid inlining call sites in unreachable-terminated block
Summary:
If the normal destination of the invoke or the parent block of the call site is unreachable-terminated, there is little point in inlining the call site unless there is literally zero cost. Unlike my previous change (D15289), this change specifically handle the call sites followed by unreachable in the same basic block for call or in the normal destination for the invoke. This change could be a reasonable first step to conservatively inline call sites leading to an unreachable-terminated block while BFI / BPI is not yet available in inliner.

Reviewers: manmanren, majnemer, hfinkel, davidxl, mcrosier, dblaikie, eraman

Subscribers: dblaikie, davidxl, mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D16616

llvm-svn: 259403
2016-02-01 20:55:11 +00:00
Sanjay Patel 04f792bdc9 [InstCombine] simplify masked store intrinsics with all ones or zeros masks
A masked store with a zero mask means there's no store.
A masked store with an allOnes mask means it's a normal vector store.

This is a continuation of:
http://reviews.llvm.org/rL259369

llvm-svn: 259392
2016-02-01 19:39:52 +00:00
Matthew Simpson 45dee06177 Add test case missing from r259357 (NFC)
llvm-svn: 259385
2016-02-01 19:09:24 +00:00
Sanjay Patel cf57c5a4ee fix broken check lines
Without the colon, it doesn't mean anything!

llvm-svn: 259377
2016-02-01 17:46:18 +00:00
David Majnemer f8853ae7b3 [InstCombine] Don't transform (X+INT_MAX)>=(Y+INT_MAX) -> (X<=Y)
This miscompile came about because we tried to use a transform which was
only appropriate for xor operators when addition was present.

This fixes PR26407.

llvm-svn: 259375
2016-02-01 17:37:56 +00:00
Jun Bum Lim ca832660ae [ValueTracking] Improve isKnownNonZero for PHI of non-zero constants
It is clear that a PHI is a non-zero if all incoming values are non-zero constants.

llvm-svn: 259370
2016-02-01 17:03:07 +00:00
Sanjay Patel b695c5557c [InstCombine] simplify masked load intrinsics with all ones or zeros masks
A masked load with a zero mask means there's no load.
A masked load with an allOnes mask means it's a normal vector load.

Differential Revision: http://reviews.llvm.org/D16691

llvm-svn: 259369
2016-02-01 17:00:10 +00:00
Matthew Simpson c578d67407 Reapply commit r258404 with fix.
The previous patch caused PR26364. The fix is to ensure that we don't enter a
cycle when iterating over use-def chains.

llvm-svn: 259357
2016-02-01 13:38:29 +00:00
Matt Arsenault 56c079f393 InstCombine: fabs(x) * fabs(x) -> x * x
llvm-svn: 259295
2016-01-30 05:02:00 +00:00
Fiona Glaser b417d464e6 Add LoopSimplifyCFG pass
Loop transformations can sometimes fail because the loop, while in
valid rotated LCSSA form, is not in a canonical CFG form. This is
an extremely simple pass that just merges obviously redundant
blocks, which can be used to fix some known failure cases. In the
future, it may be enhanced with more cases (and have code shared with
SimplifyCFG).

This allows us to run LoopSimplifyCFG -> LoopRotate -> LoopUnroll,
so that SimplifyCFG cleans up the loop before Rotate tries to run.

Not currently used in the pass manager, since this pass doesn't do
anything unless you can hook it up in an LPM with other loop passes.
It'll be added once Chandler cleans up things to allow this.

Tested in a custom pipeline out of tree to confirm it works in
practice (in addition to the included trivial test).

llvm-svn: 259256
2016-01-29 22:35:36 +00:00
Sanjay Patel 66fff73c76 [InstCombine] avoid an insertelement transformation that induces the opposite extractelement fold (PR26354)
We would infinite loop because we created a shufflevector that was wider than
needed and then failed to combine that with the insertelement. When subsequently
visiting the extractelement from that shuffle, we see that it's unnecessary,
delete it, and trigger another visit to the insertelement.

llvm-svn: 259236
2016-01-29 20:21:02 +00:00
Sanjoy Das 69b4a41fed [RS4GC] Remove unnecessary redirections from tests; NFC
llvm-svn: 259204
2016-01-29 16:32:30 +00:00
Sanjoy Das f3a4ee7542 [RS4GC] Add some missing tests and CHECK: lines
I missed porting these in rL259129.

llvm-svn: 259203
2016-01-29 16:32:25 +00:00
David Majnemer b2416bd2a7 Revert "Reapply commit r258404 with fix"
This reverts commit r258929, it caused PR26364.

llvm-svn: 259148
2016-01-29 02:43:22 +00:00
Sanjoy Das 0407108020 [RS4GC] Clamp UseDeoptBundles to true and update tests
The full diff for the test directory may be hard to read because of the
filename clash; so here's all that happened as far as the tests are
concerned:

```
cd test/Transforms/RewriteStatepointsForGC
git rm *ll
git mv deopt-bundles/* ./
rmdir deopt-bundles
find . -name '*.ll' | xargs gsed -i 's/-rs4gc-use-deopt-bundles //g'
```

llvm-svn: 259129
2016-01-29 00:28:57 +00:00
Sanjoy Das 877a101597 [RS4GC] Port three tests to the deopt bundles directory
two-invokes-one-landingpad.ll was only moved (and not "ported"), but
having everything in the `deopt-bundles` directory will make later
changes more obvious.

llvm-svn: 259125
2016-01-29 00:13:26 +00:00
Easwaran Raman 30a93c1848 Lower inlining threshold when the caller has minsize attribute.
When the caller has optsize attribute, we reduce the inlinining threshold
to OptSizeThreshold (=75) if it is not already lower than that. We don't do
the same for minsize and I suspect it was not intentional. This also addresses
a FIXME regarding checking optsize attribute explicitly instead of using the
right wrapper.

Differential Revision: http://reviews.llvm.org/D16493

llvm-svn: 259120
2016-01-28 23:44:41 +00:00
Sanjoy Das 6f9d6b6ef8 [RS4GC] Change opt %s to opt < %s; NFC
This is as per http://llvm.org/docs/TestingGuide.html#fragile-tests.  I
didn't touch the tests outside deopt-bundles/ since they'll be gone
soon.

llvm-svn: 259097
2016-01-28 21:51:21 +00:00
Sanjoy Das f7302c8baf [PlaceSafepoints] Clamp NoStatepoints to true
This change permanently clamps -spp-no-statepoints to true (the code
deletion will come later).  Tests that specifically tested
PlaceSafepoint's ability to wrap calls in gc.statepoint have been moved
to RS4GC's test suite.

llvm-svn: 259096
2016-01-28 21:51:14 +00:00
Sanjay Patel 8123f9195c add masked intrinsic tests to show missed opportunities
llvm-svn: 259083
2016-01-28 19:54:20 +00:00
Sanjoy Das 2321a4cd71 [PlaceSafepoints] Clean up tests; NFC
Use `opt < %s` instead of `opt %s` as specified in
http://llvm.org/docs/TestingGuide.html#fragile-tests.

llvm-svn: 259062
2016-01-28 18:01:03 +00:00
Sanjoy Das 52e67e7611 [PlaceSafepoints] Minor test cleanup; NFC
There is no need to place quotes around some_call and
personality_function.

llvm-svn: 259055
2016-01-28 16:11:27 +00:00
Sanjoy Das 7a2e2bed67 [LICM] Keep metadata on control equivalent hoists
Summary:
If the instruction we're hoisting out of a loop into its preheader is
guaranteed to have executed in the loop, then the metadata associated
with the instruction (e.g. !range or !dereferenceable) is valid in the
preheader.  This is because once we're in the preheader, we know we're
eventually going to reach the location the metadata was valid at.

This change makes LICM smarter around this, and helps it recognize cases
like these:

```
  do {
    int a = *ptr; !range !0
    ...
  } while (i++ < N);
```

to

```
  int a = *ptr; !range !0
  do {
    ...
  } while (i++ < N);
```

Earlier we'd drop the `!range` metadata after hoisting the load from
`ptr`.

Reviewers: igor-laevsky

Subscribers: mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D16669

llvm-svn: 259053
2016-01-28 15:51:58 +00:00
Evgeniy Stepanov e257f0f671 Tweak unnamed label syntax in textual IR for easier matching in tests.
Change the unnamed label comments like
  ; <label>:8  ; preds = %1
to
  ; <label>:8:  ; preds = %1

This way lit tests can match [[LABEL]]: in both asserts and no-asserts builds.

llvm-svn: 258993
2016-01-27 21:53:08 +00:00
Sanjay Patel 5264cc772c [SimplifyCFG] limit recursion depth when speculating instructions (PR26308)
This is a fix for:
https://llvm.org/bugs/show_bug.cgi?id=26308

With the switch to using the TTI cost model in:
http://reviews.llvm.org/rL228826
...it became possible to hit a zero-cost cycle of instructions (gep -> phi -> gep...), 
so we need a cap for the recursion in DominatesMergePoint().

A recursion depth parameter was already added for a different reason in:
http://reviews.llvm.org/rL255660
...so we can just set a limit for it.

I pulled "10" out of the air and made it an independent parameter that we can play with.
It might be higher than it needs to be given the currently low default value of 
PHINodeFoldingThreshold (2). That's the starting cost value that we enter the recursion
with, and most instructions have cost set to TCC_Basic (1), so I don't think we're going
to speculate more than 2 instructions with the current parameters.

As noted in the review and the TODO comment, we can do better than just limiting recursion
depth.

Differential Revision: http://reviews.llvm.org/D16637

llvm-svn: 258971
2016-01-27 19:22:45 +00:00
John McCall 3fe604f89f Add support for objc_unsafeClaimAutoreleasedReturnValue to the
ObjC ARC Optimizer.

The main implication of this is:

1. Ensuring that we treat it conservatively in terms of optimization.
2. We put the ASM marker on it so that the runtime can recognize
objc_unsafeClaimAutoreleasedReturnValue from releaseRV.

<rdar://problem/21567064>

Patch by Michael Gottesman!

llvm-svn: 258970
2016-01-27 19:05:08 +00:00
Matthew Simpson b95861d35e Reapply commit r258404 with fix
This patch is the second attempt to reapply commit r258404. There was bug in
the initial patch and subsequent fix (mentioned below).

The initial patch caused an assertion because we were computing smaller type
sizes for instructions that cannot be demoted. The fix first determines the
instructions that will be demoted, and then applies the smaller type size to
only those instructions.

This should fix PR26239 and PR26307.

llvm-svn: 258929
2016-01-27 13:43:27 +00:00
Chen Li 5cde8389cf [IndVarSimplify] Rewrite loop exit values with their initial values from loop preheader
Summary:
This is a revised version of D13974, and the following quoted summary are from D13974

"This patch adds support to check if a loop has loop invariant conditions which lead to loop exits. If so, we know that if the exit path is taken, it is at the first loop iteration. If there is an induction variable used in that exit path whose value has not been updated, it will keep its initial value passing from loop preheader. We can therefore rewrite the exit value with
its initial value. This will help remove phis created by LCSSA and enable other optimizations like loop unswitch."

D13974 was committed but failed one lnt test. The bug was that we only checked the condition from loop exit's incoming block was a loop invariant. But there could be another condition from loop header to that incoming block not being a loop invariant. This would produce miscompiled code.

This patch fixes the issue by checking if the incoming block is loop header, and if not, don't perform the rewrite. The could be further improved by recursively checking all conditions leading to loop exit block, but I'd like to check in this simple version first and improve it with future patches.     

Reviewers: sanjoy

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D16570

llvm-svn: 258912
2016-01-27 07:40:41 +00:00
David Majnemer fccf5c6e01 Revert "Revert "[SimplifyCFG] allow speculation of exactly one expensive instruction (PR24818)""
This reverts commit r258903 which reverted r255660.  r258903 was an
accidental commit and should not have been committed.

llvm-svn: 258905
2016-01-27 02:59:41 +00:00
David Majnemer c761afd1d1 [SimplifyCFG] Don't mistake icmp of and for a tree of comparisons
SimplifyCFG tries to turn complex branch conditions into a switch.
Some of it's logic attempts to reason about bitwise arithmetic produced
by InstCombine.  InstCombine can turn things like (X == 2) || (X == 3)
into (X & 1) == 2 and so SimplifyCFG tries to detect when this occurs so
that it can produce a switch instruction.

However, the legality checking was not sufficient to determine whether
or not this had occured.  Correctly check this case by requiring that
the right-hand side of the comparison be a power of two.

This fixes PR26323.

llvm-svn: 258904
2016-01-27 02:43:28 +00:00
David Majnemer 47de2140f7 Revert "[SimplifyCFG] allow speculation of exactly one expensive instruction (PR24818)"
This reverts commit r255660.

llvm-svn: 258903
2016-01-27 02:43:22 +00:00
Aditya Nandakumar 3d0c46d489 Reassociate: Reprocess RedoInsts after each inst
Previously the RedoInsts was processed at the end of the block.
However it was possible that it left behind some instructions that
were not canonicalized.
This should guarantee that any previous instruction in the basic
block is canonicalized before we process a new instruction.

llvm-svn: 258830
2016-01-26 18:42:36 +00:00
Sanjay Patel 980b280f50 [LibCallSimplifier] fold memset(malloc(x), 0, x) --> calloc(1, x)
This is a step towards solving PR25892:
https://llvm.org/bugs/show_bug.cgi?id=25892

It won't handle the reported case. As noted by the 'TODO' comments in the patch, 
we need to relax the hasOneUse() constraint and also match patterns that include
memset_chk() and the llvm.memset() intrinsic in addition to memset().

Differential Revision: http://reviews.llvm.org/D16337

llvm-svn: 258816
2016-01-26 16:17:24 +00:00
Matthew Simpson 61d5a18469 Revert "Reapply commit r258404 with fix"
This commit exposes a crash in computeKnownBits on the Chromium buildbots.
Reverting to investigate.

Reference: https://llvm.org/bugs/show_bug.cgi?id=26307
llvm-svn: 258812
2016-01-26 15:45:49 +00:00
Haicheng Wu f1c00a22be [LIR] Add support for structs and hand unrolled loops
This is a recommit of r258620 which causes PR26293.

The original message:

Now LIR can turn following codes into memset:

typedef struct foo {
  int a;
  int b;
} foo_t;

void bar(foo_t *f, unsigned n) {
  for (unsigned i = 0; i < n; ++i) {
    f[i].a = 0;
    f[i].b = 0;
  }
}

void test(foo_t *f, unsigned n) {
  for (unsigned i = 0; i < n; i += 2) {
    f[i] = 0;
    f[i+1] = 0;
  }
}

llvm-svn: 258777
2016-01-26 02:27:47 +00:00
Dan Gohman 75452734e4 Followup to 258750; update more tests to use .p2align .
llvm-svn: 258755
2016-01-26 00:35:07 +00:00
Evgeniy Stepanov fbc3da577c [cfi] Cross-DSO CFI diagnostic mode (LLVM part).
* __cfi_check gets a 3rd argument: ubsan handler data
* Instead of trapping on failure, call __cfi_check_fail which must be
  present in the module (generated in the frontend).

llvm-svn: 258746
2016-01-25 23:35:03 +00:00
Lawrence Hu d3d51061fb Enable loopreroll to rerool loop with pointer induction variable.
Example:

while (buf !=end ) {
   S += buf[0];
   S += buf[1];
   buf +=2;
};

Differential Revision: http://reviews.llvm.org/D13151

llvm-svn: 258709
2016-01-25 19:43:45 +00:00
Lawrence Hu b917cd9fa6 Undo commit 258700 due to missing commit message
llvm-svn: 258708
2016-01-25 19:36:30 +00:00
Matthew Simpson cfe5e2c846 Reapply commit r25804 with fix
We were hitting an assertion because we were computing smaller type sizes for
instructions that cannot be demoted. The fix first determines the instructions
that will be demoted, and then applies the smaller type size to only those
instructions.

This should fix PR26239.

llvm-svn: 258705
2016-01-25 19:24:29 +00:00
Quentin Colombet a392810bea Speculatively revert r258620 as it is the likely culprid of PR26293.
llvm-svn: 258703
2016-01-25 19:12:49 +00:00
Lawrence Hu 84b6195e41 Differential Revision: http://reviews.llvm.org/D13151
llvm-svn: 258700
2016-01-25 18:53:39 +00:00
Igor Breger 6d421419db AVX1 : Enable vector masked_load/store to AVX1.
Use AVX1 FP instructions (vmaskmovps/pd) in place of the AVX2 int instructions (vpmaskmovd/q).

Differential Revision: http://reviews.llvm.org/D16528

llvm-svn: 258675
2016-01-25 10:17:11 +00:00
Haicheng Wu dd5e9d2159 [LIR] Add support for structs and hand unrolled loops
Now LIR can turn following codes into memset:

typedef struct foo {
  int a;
  int b;
} foo_t;

void bar(foo_t *f, unsigned n) {
  for (unsigned i = 0; i < n; ++i) {
    f[i].a = 0;
    f[i].b = 0;
  }
}

void test(foo_t *f, unsigned n) {
  for (unsigned i = 0; i < n; i += 2) {
    f[i] = 0;
    f[i+1] = 0;
  }
}

llvm-svn: 258620
2016-01-23 06:52:41 +00:00
David Majnemer 6e51070dda [PruneEH] Don't try to insert a terminator after another terminator
LLVM's BasicBlock has a single terminator, it is not valid to have two.

llvm-svn: 258616
2016-01-23 06:00:44 +00:00
Matt Arsenault 8aa5678125 AMDGPU: Replace some deprecated intrinsic uses in tests
llvm-svn: 258614
2016-01-23 05:42:49 +00:00
David Majnemer 4bf0b6b483 [PruneEH] FuncletPads must not have undef operands
Instead of RAUW with undef, replace the first non-token instruction with
unreachable.

This fixes PR26263.

llvm-svn: 258611
2016-01-23 05:41:29 +00:00
Matt Arsenault bef34e21c7 AMDGPU: Rename intrinsics to use amdgcn prefix
The intrinsic target prefix should match the target name
as it appears in the triple.

This is not yet complete, but gets most of the important ones.
llvm.AMDGPU.* intrinsics used by mesa and libclc are still handled
for compatability for now.

llvm-svn: 258557
2016-01-22 21:30:34 +00:00
Sergei Larin 94be2dee7e Make sure that any new and optimized objects created during GlobalOPT copy all the attributes from the base object.
Summary:
Make sure that any new and optimized objects created during GlobalOPT copy all the attributes from the base object.

A good example of improper behavior in the current implementation is section information associated with the GlobalObject. If a section was set for it, and GlobalOpt is creating/modifying a new object based on this one (often copying the original name), without this change new object will be placed in a default section, resulting in inappropriate properties of the new variable.
The argument here is that if customer specified a section for a variable, any changes to it that compiler does should not cause it to change that section allocation.
Moreover, any other properties worth representation in copyAttributesFrom() should also be propagated.

Reviewers: jmolloy, joker-eph, joker.eph

Subscribers: slarin, joker.eph, rafael, tobiasvk, llvm-commits

Differential Revision: http://reviews.llvm.org/D16074

llvm-svn: 258556
2016-01-22 21:18:20 +00:00
Sanjoy Das 95639746e5 [PlaceSafepoints] Introduce a -spp-no-statepoints flag
Summary:
This change adds a `-spp-no-statepoints` flag to PlaceSafepoints that
bypasses the code that wraps newly introduced polls and existing calls
in gc.statepoint.  With `-spp-no-statepoints` enabled, PlaceSafepoints
effectively becomes a safpeoint **poll** insertion pass.

The eventual goal is to "constant fold" this option, along with
`-rs4gc-use-deopt-bundles` to `true`, once clients using gc.statepoint
are okay doing so.

Reviewers: pgavlin, reames, JosephTremoulet

Subscribers: sanjoy, mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D16439

llvm-svn: 258551
2016-01-22 21:02:55 +00:00
David L Kreitzer 4d7257dfa1 Fix for two constant propagation problems in GVN with the assume intrinsic
instruction.

Patch by Yuanrui Zhang.

Differential Revision: http://reviews.llvm.org/D16100

llvm-svn: 258435
2016-01-21 21:32:35 +00:00
Sanjay Patel fcc7c1a0ba [LibCallSimplifier] don't get fooled by a fake fmin()
This is similar to the bug/fix:
https://llvm.org/bugs/show_bug.cgi?id=26211
http://reviews.llvm.org/rL258325

The fmin() test case reveals another bug caused by sloppy
code duplication. It will crash without this patch because
fp128 is a valid floating-point type, but we would think
that we had matched a function that used doubles.

The new helper function can be used to replace similar
checks that are used in several other places in this file.

llvm-svn: 258428
2016-01-21 20:19:54 +00:00
David Majnemer 3af5bf30e3 [InstCombine] Simplify (x >> y) <= x
This commit extends the patterns recognised by InstSimplify to also handle (x >> y) <= x in the same way as (x /u y) <= x.

The missing optimisation was found investigating why LLVM did not optimise away bound checks in a binary search: https://github.com/rust-lang/rust/pull/30917

Patch by Andrea Canciani!

Differential Revision: http://reviews.llvm.org/D16402

llvm-svn: 258422
2016-01-21 18:55:54 +00:00
Rong Xu ed9fec7365 [PGO] IR level instrumentation of indirect call value profiling
This patch adds the instrumentation for indirect call value profiling. It finds all the indirect call-sites and generates instrprof_value_profile intrinsic calls. A new opt level option -disable-vp is introduced to disable this instrumentation.

Reviewers: davidxl, betulb, vsk

Differential Revision: http://reviews.llvm.org/D16016

llvm-svn: 258417
2016-01-21 18:11:44 +00:00
Matthew Simpson 486bace5cc Revert "[SLP] Truncate expressions to minimum required bit width"
This reverts commit r258404.

llvm-svn: 258408
2016-01-21 17:17:20 +00:00
Vedant Kumar 61035fa3cb [GCOV] Avoid emitting profile arcs for module and skeleton CUs
Do not emit profile arc files and note files for module and skeleton
CU's.

Our users report seeing unexpected *.gcda and *.gcno files in their
projects when using gcov-style profiling with modules or frameworks.
The unwanted files come from these modules. This is not very helpful
for end-users. Further, we've seen reports of instrumented programs
crashing while writing these files out (due to I/O failures).

rdar://problem/22838296

Reviewed-by: aprantl

Differential Revision: http://reviews.llvm.org/D15997

llvm-svn: 258406
2016-01-21 17:04:42 +00:00
Matthew Simpson cb17d72170 [SLP] Truncate expressions to minimum required bit width
This change attempts to produce vectorized integer expressions in bit widths
that are narrower than their scalar counterparts. The need for demotion arises
especially on architectures in which the small integer types (e.g., i8 and i16)
are not legal for scalar operations but can still be used in vectors. Like
similar work done within the loop vectorizer, we rely on InstCombine to perform
the actual type-shrinking. We use the DemandedBits analysis and
ComputeNumSignBits from ValueTracking to determine the minimum required bit
width of an expression.

Differential revision: http://reviews.llvm.org/D15815

llvm-svn: 258404
2016-01-21 16:31:55 +00:00
Sanjoy Das a34ce95b60 Add a "gc-transition" operand bundle
Summary:
This adds a new kind of operand bundle to LLVM denoted by the
`"gc-transition"` tag.  Inputs to `"gc-transition"` operand bundle are
lowered into the "transition args" section of `gc.statepoint` by
`RewriteStatepointsForGC`.

This removes the last bit of functionality that was unsupported in the
deopt bundle based code path in `RewriteStatepointsForGC`.

Reviewers: pgavlin, JosephTremoulet, reames

Subscribers: sanjoy, mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D16342

llvm-svn: 258338
2016-01-20 19:50:25 +00:00
Sanjay Patel bd2dc67142 [LibCallSimplifier] don't get fooled by a fake sqrt()
The test case will crash without this patch because the subsequent call to
hasUnsafeAlgebra() assumes that the call instruction is an FPMathOperator
(ie, returns an FP type).

This part of the function signature check was omitted for the sqrt() case, 
but seems to be in place for all other transforms.

Before:
http://reviews.llvm.org/rL257400
...we would have needlessly continued execution in optimizeSqrt(), but the
bug was harmless because we'd eventually fail some other check and return
without damage.

This should fix:
https://llvm.org/bugs/show_bug.cgi?id=26211

Differential Revision: http://reviews.llvm.org/D16198

llvm-svn: 258325
2016-01-20 17:41:14 +00:00
Joseph Tremoulet b41632bf0f [Inliner/WinEH] Honor implicit nounwinds
Summary:
Funclet EH tables require that a given funclet have only one unwind
destination for exceptional exits.  The verifier will therefore reject
e.g. two cleanuprets with different unwind dests for the same cleanup, or
two invokes exiting the same funclet but to different unwind dests.
Because catchswitch has no 'nounwind' variant, and because IR producers
are not *required* to annotate calls which will not unwind as 'nounwind',
it is legal to nest a call or an "unwind to caller" catchswitch within a
funclet pad that has an unwind destination other than caller; it is
undefined behavior for such a call or catchswitch to unwind.

Normally when inlining an invoke, calls in the inlined sequence are
rewritten to invokes that unwind to the callsite invoke's unwind
destination, and "unwind to caller" catchswitches in the inlined sequence
are rewritten to unwind to the callsite invoke's unwind destination.
However, if such a call or "unwind to caller" catchswitch is located in a
callee funclet that has another exceptional exit with an unwind
destination within the callee, applying the normal transformation would
give that callee funclet multiple unwind destinations for its exceptional
exits.  There would be no way for EH table generation to determine which
is the "true" exit, and the verifier would reject the function
accordingly.

Add logic to the inliner to detect these cases and leave such calls and
"unwind to caller" catchswitches as calls and "unwind to caller"
catchswitches in the inlined sequence.

This fixes PR26147.


Reviewers: rnk, andrew.w.kaylor, majnemer

Subscribers: alexcrichton, llvm-commits

Differential Revision: http://reviews.llvm.org/D16319

llvm-svn: 258273
2016-01-20 02:15:15 +00:00
Sanjay Patel 582857c95c add tests to show missing memset/malloc optimizations (PR25892)
llvm-svn: 258218
2016-01-19 23:07:10 +00:00
Sanjoy Das 29a4b5dc0d [SCEV] Fix PR26207
In some cases, the max backedge taken count can be more conservative
than the exact backedge taken count (for instance, because
ScalarEvolution::getRange is not control-flow sensitive whereas
computeExitLimitFromICmp can be).  In these cases,
computeExitLimitFromCond (specifically the bit that deals with `and` and
`or` instructions) can create an ExitLimit instance with a
`SCEVCouldNotCompute` max backedge count expression, but a computable
exact backedge count expression.  This violates an implicit SCEV
assumption: a computable exact BE count should imply a computable max BE
count.

This change

 - Makes the above implicit invariant explicit by adding an assert to
   ExitLimit's constructor

 - Changes `computeExitLimitFromCond` to be more robust around
   conservative max backedge counts

llvm-svn: 258184
2016-01-19 20:53:51 +00:00
Sanjay Patel d1f4f03f5e [LibCallSimplifier] use instruction-level fast-math-flags to shrink calls
This is a continuation of adding FMF to call instructions:
http://reviews.llvm.org/rL255555

llvm-svn: 258158
2016-01-19 18:38:52 +00:00
Sanjay Patel 81a63cd11f [LibCallSimplifier] use instruction-level fast-math-flags to transform pow(x, [small integer]) calls
This is a continuation of adding FMF to call instructions:
http://reviews.llvm.org/rL255555

As with D15937, the intent of the patch is to preserve the current behavior of the transform
except that we use the pow call's 'fast' attribute as a trigger rather than a function-level
attribute.

The TODO comment notes a potential follow-on patch that would propagate FMF to the new
instructions.

Differential Revision: http://reviews.llvm.org/D16122

llvm-svn: 258153
2016-01-19 18:15:12 +00:00
Sanjoy Das de47590589 [IndVars] Fix PR25576
`LCSSASafePhiForRAUW` as computed was incorrect -- in cases like
these (this exact example does not actually trigger the bug):

define i32 @f(i32 %n, i1* %c) {
entry:
  br label %outer.loop

outer.loop:
  br label %inner.loop

inner.loop:
  %iv = phi i32 [ 0, %outer.loop ], [ %iv.inc, %inner.loop ]
  %iv.inc = add nuw nsw i32 %iv, 1
  %tc = udiv i32 %n, 13
  %be.cond = icmp ult i32 %iv, %tc
  br i1 %be.cond, label %inner.loop, label %inner.exit

inner.exit:
  %iv.lcssa = phi i32 [ %iv, %inner.loop ]
  %outer.be.cond = load volatile i1, i1* %c
  br i1 %outer.be.cond, label %outer.loop, label %leave

leave:
  %iv.lcssa.lcssa = phi i32 [ %iv.lcssa, %inner.exit ]
  ret i32 %iv.lcssa.lcssa
}

`LCSSASafePhiForRAUW` is true for `%iv.lcssa` when re-rewriting the exit
value of `%iv` for `%inner.loop` to `%tc` (this can happen due to
`SCEVExpander::findExistingExpansion`), but the RAUW breaks LCSSA.

To fix this, instead of computing `SafePhi` with special logic, decide
the safety of RAUW directly via `replacementPreservesLCSSAForm`.

llvm-svn: 258016
2016-01-17 18:12:52 +00:00
Artur Pilipenko f84dc06e5b Push isDereferenceableAndAlignedPointer down into isSafeToLoadUnconditionally
Reviewed By: reames

Differential Revision: http://reviews.llvm.org/D16226

llvm-svn: 258010
2016-01-17 12:35:29 +00:00
Igor Laevsky 28eeb3f66c [BasicAliasAnalysis] Take into account operand bundles in the getModRefInfo function
Differential Revision: http://reviews.llvm.org/D16225

llvm-svn: 257991
2016-01-16 12:15:53 +00:00
Matthew Simpson 57fe1b10db Reapply r257800 with fix
The fix uniques the bundle of getelementptr indices we are about to vectorize
since it's possible for the same index to be used by multiple instructions.
The original commit message is below.

[SLP] Vectorize the index computations of getelementptr instructions.

This patch seeds the SLP vectorizer with getelementptr indices. The primary
motivation in doing so is to vectorize gather-like idioms beginning with
consecutive loads (e.g., g[a[0] - b[0]] + g[a[1] - b[1]] + ...). While these
cases could be vectorized with a top-down phase, seeding the existing bottom-up
phase with the index computations avoids the complexity, compile-time, and
phase ordering issues associated with a full top-down pass. Only bundles of
single-index getelementptrs with non-constant differences are considered for
vectorization.

llvm-svn: 257918
2016-01-15 18:51:51 +00:00
Silviu Baranga f29dfd36bb Re-commit r257064, after it was reverted in r257340.
This contains a fix for the issue that caused the revert:
we no longer assume that we can insert instructions after the
instruction that produces the base pointer. We previously
assumed that this would be ok, because the instruction produces
a value and therefore is not a terminator. This is false for invoke
instructions. We will now insert these new instruction directly
at the location of the users.

Original commit message:

[InstCombine] Look through PHIs, GEPs, IntToPtrs and PtrToInts to expose more constants when comparing GEPs

Summary:
When comparing two GEP instructions which have the same base pointer
and one of them has a constant index, it is possible to only compare
indices, transforming it to a compare with a constant. This removes
one use for the GEP instruction with the constant index, can reduce
register pressure and can sometimes lead to removing the comparisson
entirely.

InstCombine was already doing this when comparing two GEPs if the base
pointers were the same. However, in the case where we have complex
pointer arithmetic (GEPs applied to GEPs, PHIs of GEPs, conversions to
or from integers, etc) the value of the original base pointer will be
hidden to the optimizer and this transformation will be disabled.

This change detects when the two sides of the comparison can be
expressed as GEPs with the same base pointer, even if they don't
appear as such in the IR. The transformation will convert all the
pointer arithmetic to arithmetic done on indices and all the relevant
uses of GEPs to GEPs with a common base pointer. The GEP comparison
will be converted to a comparison done on indices.

Reviewers: majnemer, jmolloy

Subscribers: hfinkel, jevinskie, jmolloy, aadg, llvm-commits

Differential Revision: http://reviews.llvm.org/D15146

llvm-svn: 257897
2016-01-15 15:52:05 +00:00
Matthew Simpson 9258e013a2 Revert "[SLP] Vectorize the index computations of getelementptr instructions."
This reverts commit r257800.

llvm-svn: 257888
2016-01-15 13:10:46 +00:00
James Molloy f01488e2bc [InstCombine] Rewrite bswap/bitreverse handling completely.
There are several requirements that ended up with this design;
  1. Matching bitreversals is too heavyweight for InstCombine and doesn't really need to be done so early.
  2. Bitreversals and byteswaps are very related in their matching logic.
  3. We want to implement support for matching more advanced bswap/bitreverse patterns like partial bswaps/bitreverses.
  4. Bswaps are best matched early in InstCombine.

The result of these is that a new utility function is created in Transforms/Utils/Local.h that can be configured to search for bswaps, bitreverses or both. InstCombine uses it to find only bswaps, CGP uses it to find only bitreversals.

We can then extend the matching logic in one place only.

llvm-svn: 257875
2016-01-15 09:20:19 +00:00
Keno Fischer 81e2e9ef86 Reapply r257105 "[Verifier] Check that debug values have proper size"
I originally reapplied this in 257550, but had to revert again due to bot
breakage. The only change in this version is to allow either the TypeSize
or the TypeAllocSize of the variable to be the one represented in debug info
(hopefully in the future we can figure out how to encode the difference).
Additionally, several bot failures following r257550, were due to
optimizer bugs now fixed in r257787 and r257795.

r257550 commit message was:

```
The follow extra changes were made to test cases:

Manually making the variable be the actual type instead of a pointer
to avoid pointer-size differences in generic code:

    LLVM :: DebugInfo/Generic/2010-03-24-MemberFn.ll
    LLVM :: DebugInfo/Generic/2010-04-06-NestedFnDbgInfo.ll
    LLVM :: DebugInfo/Generic/2010-05-03-DisableFramePtr.ll
    LLVM :: DebugInfo/Generic/varargs.ll

Delete sizing information from debug info for the same reason
(but the presence of the pointer was important to the test case):

    LLVM :: DebugInfo/Generic/restrict.ll
    LLVM :: DebugInfo/Generic/tu-composite.ll
    LLVM :: Linker/type-unique-type-array-a.ll
    LLVM :: Linker/type-unique-simple2.ll

Fixing an incorrect DW_OP_deref

    LLVM :: DebugInfo/Generic/2010-05-03-OriginDIE.ll

Fixing a missing DW_OP_deref

    LLVM :: DebugInfo/Generic/incorrect-variable-debugloc.ll

Additionally, clang should no longer complain during bootstrap should no
longer happen after r257534.

The original commit message was:
``
Summary:
Teach the Verifier to make sure that the storage size given to llvm.dbg.declare
or the value size given to llvm.dbg.value agree with what is declared in
DebugInfo. This is implicitly assumed in a number of passes (e.g. in SROA).
Additionally this catches a number of common mistakes, such as passing a
pointer when a value was intended or vice versa.

One complication comes from stack coloring which modifies the original IR when
it merges allocas in order to make sure that if AA falls back to the IR it gets
the correct result. However, given this new invariant, indiscriminately
replacing one alloca by a different (differently sized one) is no longer valid.
Fix this by just undefing out any use of the alloca in a dbg.declare in this
case.

Additionally, I had to fix a number of test cases. Of particular note:
- I regenerated dbg-changes-codegen-branch-folding.ll from the given source as
  it was affected by the bug fixed in r256077
- two-cus-from-same-file.ll was changed to avoid having a variable-typed debug
  variable as that would depend on the target, even though this test is
  supposed to be generic
- I had to manually declared size/align for reference type. See also the
  discussion for D14275/r253186.
- fpstack-debuginstr-kill.ll required changing `double` to `long double`
- most others were just a question of adding OP_deref
``

```

llvm-svn: 257850
2016-01-15 00:46:17 +00:00
Matthew Simpson 791fd160c3 [SLP] Vectorize the index computations of getelementptr instructions.
This patch seeds the SLP vectorizer with getelementptr indices. The primary
motivation in doing so is to vectorize gather-like idioms beginning with
consecutive loads (e.g., g[a[0] - b[0]] + g[a[1] - b[1]] + ...). While these
cases could be vectorized with a top-down phase, seeding the existing bottom-up
phase with the index computations avoids the complexity, compile-time, and
phase ordering issues associated with a full top-down pass. Only bundles of
single-index getelementptrs with non-constant differences are considered for
vectorization.

Differential Revision: http://reviews.llvm.org/D14829

llvm-svn: 257800
2016-01-14 20:46:27 +00:00
Keno Fischer d5354fdddb [SROA] Also insert a bit piece expression if only one piece is needed
Summary: If SROA creates only one piece (e.g. because the other is not needed),
it still needs to create a bit_piece expression if that bit piece is smaller
than the original size of the alloca.

Reviewers: aprantl

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D16187

llvm-svn: 257795
2016-01-14 20:06:34 +00:00