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Commit Graph

1475 Commits

Author SHA1 Message Date
David Green
086b5443c9 [DA] Delinearise AddRecs if we can prove they don't wrap
We can prove that some delinearized subscripts do not wrap around to become
negative by the fact that they are from inbound geps of load/store locations.
This helps improve the delinearisation in cases where we can't prove that they
are non-negative from SCEV alone.

Differential Revision: https://reviews.llvm.org/D48481

llvm-svn: 335481
2018-06-25 15:13:26 +00:00
Simon Pilgrim
d34cfc19bf [CostModel][AArch64] Add some initial costs for SK_Select and SK_PermuteSingleSrc
AArch64 was only setting costs for SK_Transpose, which meant that many of the simpler shuffles (e.g. SK_Select and SK_PermuteSingleSrc for larger vector elements) was being severely overestimated by the default shuffle expansion.

This patch adds costs to help improve SLP performance and avoid a regression in reductions introduced by D48174.

I'm not very knowledgeable about AArch64 shuffle lowering so I've kept the extra costs to a minimum - someone who knows this code can add extra costs which should improve vectorization a lot more.

Differential Revision: https://reviews.llvm.org/D48172

llvm-svn: 335329
2018-06-22 09:45:31 +00:00
Tim Shen
ebe290e6fc [SCEV] Re-apply r335197 (with Polly fixes).
Summary:
This initiates a discussion on changing Polly accordingly while re-applying r335197 (D48338).

I have never worked on Polly. The proposed change to param_div_div_div_2.ll is not educated, but just patterns that match the output.

All LLVM files are already reviewed in D48338.

Reviewers: jdoerfert, bollu, efriedma

Subscribers: jlebar, sanjoy, hiraditya, llvm-commits, bixia

Differential Revision: https://reviews.llvm.org/D48453

llvm-svn: 335292
2018-06-21 21:29:54 +00:00
Nicolai Haehnle
f58aee7cea AMDGPU: Convert test cases to the dimension-aware intrinsics
Summary:
Also explicitly port over some tests in llvm.amdgcn.image.* that were
missing. Some tests are removed because they no longer apply (i.e.
explicitly testing building an address vector via insertelement).

This is in preparation for the eventual removal of the old-style
intrinsics.

Some additional notes:
- constant-address-space-32bit.ll: change some GCN-NEXT to GCN because
  the instruction schedule was subtly altered
- insert_vector_elt.ll: the old test didn't actually test anything,
  because %tmp1 was not used; remove the load, because it doesn't work
  (Because of the amdgpu_ps calling convention? In any case, it's
  orthogonal to what the test claims to be testing.)

Change-Id: Idfa99b6512ad139e755e82b8b89548ab08f0afcf

Reviewers: arsenm, rampitec

Subscribers: MatzeB, qcolombet, kzhuravl, wdng, yaxunl, dstuttard, tpr, t-tye, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D48018

llvm-svn: 335229
2018-06-21 13:37:19 +00:00
David Green
e74f29c6a3 [DA] Enable -da-delinearize by default
This enables da-delinearize in Dependence Analysis for delinearizing array
accesses into multiple dimensions. This can help to increase the power of
Dependence analysis on multi-dimensional arrays and prevent having to fall
back to the slower and less accurate MIV tests. It adds static checks on the
bounds of the arrays to ensure that one dimension doesn't overflow into
another, and brings our code in line with our tests.

Differential Revision: https://reviews.llvm.org/D45872

llvm-svn: 335217
2018-06-21 11:53:16 +00:00
Simon Pilgrim
fe48f7ae99 [X86][AVX] Reduce v4f64/v4i64 shuffle costs (PR37882)
These were being over cautious for costs for one/two op general shuffles - VSHUFPD doesn't have to replicate the same shuffle in both lanes like VSHUFPS does. 

llvm-svn: 335216
2018-06-21 11:37:13 +00:00
Tim Shen
b5fa204da6 Revert "[SCEV] Improve zext(A /u B) and zext(A % B)"
This reverts commit r335197, as some bots are not happy.

llvm-svn: 335198
2018-06-21 02:15:32 +00:00
Tim Shen
b896249b52 [SCEV] Improve zext(A /u B) and zext(A % B)
Summary:
Try to match udiv and urem patterns, and sink zext down to the leaves.

I'm not entirely sure why some unrelated tests change, but the added <nsw>s seem right.

Reviewers: sanjoy

Subscribers: jlebar, hiraditya, bixia, llvm-commits

Differential Revision: https://reviews.llvm.org/D48338

llvm-svn: 335197
2018-06-21 01:49:07 +00:00
Roman Lebedev
bccf832eec [NFC][SCEV] Add tests related to bit masking (PR37793)
Summary:
Related to https://bugs.llvm.org/show_bug.cgi?id=37793, https://reviews.llvm.org/D46760#1127287

We'd like to do this canonicalization https://rise4fun.com/Alive/Gmc
But it is currently restricted by rL155136 / rL155362, which says:
```
    // This is a constant shift of a constant shift. Be careful about hiding
    // shl instructions behind bit masks. They are used to represent multiplies
    // by a constant, and it is important that simple arithmetic expressions
    // are still recognizable by scalar evolution.
    //
    // The transforms applied to shl are very similar to the transforms applied
    // to mul by constant. We can be more aggressive about optimizing right
    // shifts.
    //
    // Combinations of right and left shifts will still be optimized in
    // DAGCombine where scalar evolution no longer applies.
```

I think these tests show that for *constants*, SCEV has no issues with that canonicalization.

Reviewers: mkazantsev, spatel, efriedma, sanjoy

Reviewed By: mkazantsev

Subscribers: sanjoy, javed.absar, llvm-commits, stoklund, bixia

Differential Revision: https://reviews.llvm.org/D48229

llvm-svn: 335101
2018-06-20 07:54:11 +00:00
Sanjoy Das
49958771f0 Revert "[SCEV] Add nuw/nsw to mul ops in StrengthenNoWrapFlags"
This reverts r334428.  It incorrectly marks some multiplications as nuw.  Tim
Shen is working on a proper fix.

Original commit message:

[SCEV] Add nuw/nsw to mul ops in StrengthenNoWrapFlags where safe.

Summary:
Previously we would add them for adds, but not multiplies.

llvm-svn: 335016
2018-06-19 04:09:44 +00:00
George Burgess IV
6d5d477e04 [MSSA] Print more optimization information
In particular, when asked to print a MemoryAccess, we'll now print where
defs are optimized to, and we'll print optimized access types.

This patch also introduces an operator<< to make printing AliasResults
easier.

Patch by Juneyoung Lee!

Differential Revision: https://reviews.llvm.org/D47860

llvm-svn: 334760
2018-06-14 19:55:53 +00:00
Justin Lebar
aff7184247 [SCEV] Simplify zext/trunc idiom that appears when handling bitmasks.
Summary:
Specifically, we transform

  zext(2^K * (trunc X to iN)) to iM ->
  2^K * (zext(trunc X to i{N-K}) to iM)<nuw>

This is helpful because pulling the 2^K out of the zext allows further
optimizations.

Reviewers: sanjoy

Subscribers: hiraditya, llvm-commits, timshen

Differential Revision: https://reviews.llvm.org/D48158

llvm-svn: 334737
2018-06-14 17:13:48 +00:00
Justin Lebar
4a161bf875 [SCEV] Simplify trunc-of-add/mul to add/mul-of-trunc under more circumstances.
Summary:
Previously we would do this simplification only if it did not introduce
any new truncs (excepting new truncs which replace other cast ops).

This change weakens this condition: If the number of truncs stays the
same, but we're able to transform trunc(X + Y) to X + trunc(Y), that's
still simpler, and it may open up additional transformations.

While we're here, also clean up some duplicated code.

Reviewers: sanjoy

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D48160

llvm-svn: 334736
2018-06-14 17:13:35 +00:00
Simon Pilgrim
3567ed310e [CostModel][AArch64] Add cost tests for ALTERNATE/SELECT style shuffle masks
Precursor to fixing a regression with SLP vectorizer for supporting SELECT shuffles (vs the current ALTERNATE)

llvm-svn: 334714
2018-06-14 14:20:20 +00:00
Simon Pilgrim
e3436b5ceb [CostModel] Recognise REVERSE shuffle mask if the elements come from the second src
llvm-svn: 334698
2018-06-14 09:35:00 +00:00
Simon Pilgrim
98546e502b [CostModel][X86] Test showing failure to recognise REVERSE shuffle mask if the elements come from the second src
llvm-svn: 334623
2018-06-13 17:12:11 +00:00
Simon Pilgrim
21d47e6a7f [CostModel] Recognise BROADCAST shuffle mask if the elements come from the second src
llvm-svn: 334620
2018-06-13 16:52:02 +00:00
Simon Pilgrim
39a11cf87c [CostModel][X86] Test showing failure to recognise BROADCAST shuffle mask if the elements come from the second src
llvm-svn: 334616
2018-06-13 16:33:42 +00:00
Max Kazantsev
55e622cae0 [SimplifyIndVars] Ignore dead users
IndVarSimplify sometimes makes transforms basing on users that are trivially dead. In particular,
if DCE wasn't run before it, there may be a dead `sext/zext` in loop that will trigger widening
transforms, however it makes no sense to do it.

This patch teaches IndVarsSimplify ignore the mist trivial cases of that.

Differential Revision: https://reviews.llvm.org/D47974
Reviewed By: sanjoy

llvm-svn: 334567
2018-06-13 02:25:32 +00:00
Simon Pilgrim
f6cb95e1e4 [CostModel] Replace ShuffleKind::SK_Alternate with ShuffleKind::SK_Select (PR33744)
As discussed on PR33744, this patch relaxes ShuffleKind::SK_Alternate which requires shuffle masks to only match an alternating pattern from its 2 sources:

e.g. v4f32: <0,5,2,7> or <4,1,6,3>

This seems far too restrictive as most SIMD hardware which will implement it using a general blend/bit-select instruction, so replaces it with SK_Select, permitting elements from either source as long as they are inline:

e.g. v4f32: <0,5,2,7>, <4,1,6,3>, <0,1,6,7>, <4,1,2,3> etc.

This initial patch just updates the name and cost model shuffle mask analysis, later patch reviews will update SLP to better utilise this - it still limits itself to SK_Alternate style patterns.

Differential Revision: https://reviews.llvm.org/D47985

llvm-svn: 334513
2018-06-12 16:12:29 +00:00
Simon Pilgrim
2bfc76af15 [CostModel] Treat Identity shuffle masks as zero cost
As discussed on D47985, identity shuffle masks should probably be free.

I've limited this to the case where the input and output types all match - but we could probably accept all cases.

Differential Revision: https://reviews.llvm.org/D47986

llvm-svn: 334506
2018-06-12 14:47:13 +00:00
Simon Pilgrim
33b2c8c19d [CostModel][X86] Add extra Identity shuffle mask cost tests (D47986)
llvm-svn: 334486
2018-06-12 09:18:13 +00:00
Tim Shen
8102120351 Fix incorrect CHECK-LABEL
llvm-svn: 334434
2018-06-11 19:56:12 +00:00
Justin Lebar
f15e6b139a [SCEV] Add transform zext((A * B * ...)<nuw>) --> (zext(A) * zext(B) * ...)<nuw>.
Reviewers: sanjoy

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D48041

llvm-svn: 334429
2018-06-11 18:57:58 +00:00
Justin Lebar
6411be1800 [SCEV] Add nuw/nsw to mul ops in StrengthenNoWrapFlags where safe.
Summary:
Previously we would add them for adds, but not multiplies.

Reviewers: sanjoy

Subscribers: llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D48038

llvm-svn: 334428
2018-06-11 18:57:42 +00:00
Tim Shen
86a2946ec1 [SCEV] Canonicalize "A /u C1 /u C2" to "A /u (C1*C2)".
Summary: FWIW InstCombine already folds this. Also avoid the case where C1*C2 overflows.

Reviewers: sunfish, sanjoy

Subscribers: hiraditya, bixia, llvm-commits

Differential Revision: https://reviews.llvm.org/D47965

llvm-svn: 334425
2018-06-11 18:44:58 +00:00
Simon Pilgrim
d4b723f66d [CostModel][X86] Add 'select' style shuffle costs tests (PR33744)
llvm-svn: 334351
2018-06-09 16:08:25 +00:00
Krzysztof Parzyszek
016e021c0d [SCEV] Look through zero-extends in howFarToZero
An expression like
  (zext i2 {(trunc i32 (1 + %B) to i2),+,1}<%while.body> to i32)
will become zero exactly when the nested value becomes zero in its type.
Strip injective operations from the input value in howFarToZero to make
the value simpler.

Differential Revision: https://reviews.llvm.org/D47951

llvm-svn: 334318
2018-06-08 20:43:07 +00:00
Artur Pilipenko
fecfcf704c [BPI] Apply invoke heuristic before loop branch heuristic
Currently the loop branch heuristic is applied before the invoke heuristic which makes us overestimate the probability of the unwind destination of invokes inside loops. This in turn makes us grossly underestimate the frequencies of loops with invokes.

Reviewed By: skatkov, vsk

Differential Revision: https://reviews.llvm.org/D47371

llvm-svn: 334285
2018-06-08 13:03:21 +00:00
Simon Pilgrim
a09d4b00f9 [X86][SSE] Use multiplication scale factors for v8i16 SHL on pre-AVX2 targets.
Similar to v4i32 SHL, convert v8i16 shift amounts to scale factors instead to improve performance and reduce instruction count. We were already doing this for constant shifts, this adds variable shift support.

Reduces the serial nature of the codegen, which relies on chains of plendvb/pand+pandn+por shifts.

This is a step towards adding support for vXi16 vector rotates.

Differential Revision: https://reviews.llvm.org/D47546

llvm-svn: 334023
2018-06-05 15:17:39 +00:00
Karl-Johan Karlsson
16a7995997 [ConstantFold] Disallow folding vector geps into bitcasts
Summary:
Getelementptr returns a vector of pointers, instead of a single address,
when one or more of its arguments is a vector. In such case it is not
possible to simplify the expression by inserting a bitcast of operand(0)
into the destination type, as it will create a bitcast between different
sizes.

Reviewers: majnemer, mkuper, mssimpso, spatel

Reviewed By: spatel

Subscribers: lebedev.ri, llvm-commits

Differential Revision: https://reviews.llvm.org/D46379

llvm-svn: 333783
2018-06-01 19:34:35 +00:00
Karl-Johan Karlsson
13034d4b5f [ConstantFold] Add lit testcase for bitcast problem. NFC
llvm-svn: 333767
2018-06-01 15:08:14 +00:00
David Green
668b65bbcf [DA] Fix direction vectors for weakZeroSrcSIV
Both weakZeroSrcSIV and weakZeroDstSIV are currently giving the same
direction vectors. Fix weakZeroSrcSIVtest by flipping the directions
it gives.

Differential Revision: https://reviews.llvm.org/D46678

llvm-svn: 333658
2018-05-31 14:55:29 +00:00
Daniel Neilson
03d48f8056 [AliasSet] Teach the alias set how to handle atomic memcpy/memmove/memset
Summary:
The atomic variants of the memcpy/memmove/memset intrinsics can be treated
the same was as the regular forms, with respect to aliasing. Update the
AliasSetTracker to treat the atomic forms the same was as the regular forms.

llvm-svn: 333551
2018-05-30 14:43:39 +00:00
Daniel Neilson
6a4ca59d1b [BasicAA] Teach the analysis about atomic memcpy
Summary:
A simple change to derive mod/ref info from the atomic memcpy
intrinsic in the same way as from the regular memcpy intrinsic.

llvm-svn: 333454
2018-05-29 19:23:50 +00:00
Piotr Padlewski
fa1c9cecd2 Fix aliasing of launder.invariant.group
Summary:
Patch for capture tracking broke
bootstrap of clang with -fstict-vtable-pointers
which resulted in debbugging nightmare. It was fixed
https://reviews.llvm.org/D46900 but as it turned
out, there were other parts like inliner (computing of
noalias metadata) that I found after bootstraping with enabled
assertions.

Reviewers: hfinkel, rsmith, chandlerc, amharc, kuhar

Subscribers: JDevlieghere, eraman, llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D47088

llvm-svn: 333070
2018-05-23 09:16:44 +00:00
Simon Pilgrim
c7f0b62bae [TTI] Add uniform/non-uniform constant Pow2 detection to TargetTransformInfo::getInstructionThroughput
This enables us to detect more fast path sdiv cases under cost analysis.

This patch also enables us to handle non-uniform-constant pow2 cases for X86 SDIV costs.

Found while working on D46276

Future patches can then extend the vectorizers to more fully support non-uniform pow2 cases.

Differential Revision: https://reviews.llvm.org/D46637

llvm-svn: 332969
2018-05-22 10:40:09 +00:00
Piotr Padlewski
aa8a1694d2 Propagate nonnull and dereferenceable throught launder
Summary:
invariant.group.launder should not stop propagation
of nonnull and dereferenceable, because e.g. we would not be
able to hoist loads speculatively.

Reviewers: rsmith, amharc, kuhar, xbolva00, hfinkel

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D46972

llvm-svn: 332788
2018-05-18 23:54:33 +00:00
Piotr Padlewski
02b65158ec [MemDep] Fixed handling of invariant.group
Summary:
Memdep had funny bug related to invariant.groups - because it did not
invalidated cache, in some very rare cases it was possible to show memory
dependence of the instruction that was deleted, but because other
instruction took it's place it resulted in call to vtable!
Thanks @amharc for repro!.

Reviewers: dberlin, kuhar, amharc

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45320

Co-authored-by: Krzysztof Pszeniczny <krzysztof.pszeniczny@gmail.com>
llvm-svn: 332781
2018-05-18 22:40:34 +00:00
Serguei Katkov
bfdf0db09d [LICM] Extend the MustExecute scope
CanProveNotTakenFirstIteration utility does not handle the case when
condition of the branch is a constant. Add its handling.

Reviewers: reames, anna, mkazantsev
Reviewed By: reames
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D46996

llvm-svn: 332695
2018-05-18 04:56:28 +00:00
George Burgess IV
e4d5ef16f2 Revert r332657: "[AA] cfl-anders-aa with field sensitivity"
I don't believe the person who LGTMed this review has appropriate
context on this code. I apologize if I'm wrong.

llvm-svn: 332674
2018-05-17 21:56:39 +00:00
David Bolvansky
9905fda249 [AA] cfl-anders-aa with field sensitivity
Summary:
There was some unfinished work started for offset tracking in CFLGraph by the author of implementation of Andersen algorithm. This work was completed and support for field sensitivity was added to the core of Andersen algorithm.

The performance results seem promising.

SPEC2006 int_base score was increased by 1.1 % (I  compared clang 6.0 with clang 6.0 with this patch). The avergae compile time was increased by +- 1 % according my measures with small and medium C/C++ projects (I did not tested it on the large projects with milions of lines of code)

Reviewers: chandlerc, george.burgess.iv, rja

Reviewed By: rja

Subscribers: rja, llvm-commits

Differential Revision: https://reviews.llvm.org/D46282

llvm-svn: 332657
2018-05-17 20:23:33 +00:00
Krzysztof Pszeniczny
b3b8ba7506 [BasicAA] Fix handling of invariant group launders
Summary:
A recent patch ([[ https://reviews.llvm.org/rL331587 | rL331587 ]]) to Capture Tracking taught it that the `launder_invariant_group` intrinsic captures its argument only by returning it. Unfortunately, BasicAA still considered every call instruction as a possible escape source and hence concluded that the result of a `launder_invariant_group` call cannot alias any local non-escaping value. This led to [[ https://bugs.llvm.org/show_bug.cgi?id=37458 | bug 37458 ]].

This patch updates the relevant check for escape sources in BasicAA.

Reviewers: Prazek, kuhar, rsmith, hfinkel, sanjoy, xbolva00

Reviewed By: hfinkel, xbolva00

Subscribers: JDevlieghere, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D46900

llvm-svn: 332466
2018-05-16 13:16:54 +00:00
Michael Zolotukhin
041e33a699 [MemorySSA] Don't sort IDF blocks.
Summary:
After r332167 we started to sort the IDF blocks inside IDF calculation, so
there is no need to re-sort them on the user site. The test changes are due to
a slightly different order we're using now (originally we used DFSInNumber and
now the blocks are sorted by a pair (LevelFromRoot, DFSInNumber)).

Reviewers: dberlin, mgrang

Subscribers: Prazek, hiraditya, george.burgess.iv, llvm-commits

Differential Revision: https://reviews.llvm.org/D46899

llvm-svn: 332385
2018-05-15 18:40:29 +00:00
George Burgess IV
cef84e7236 Add regression test for r331976
In general, it's difficult to poke the ConstantExpr code in CFLAA, since
LLVM is so great at eagerly reducing ConstantExprs. :)

Sadly, this only shows a functional difference from before the patch
because CFLAA has some special logic around taking loads of non-pointers
into account. Namely, with the broken select behavior, CFLAA will
completely fail to take note of @g3. Since CFLAA doesn't have any record
about @g3 when we do an alias query for @g3 and %a, it conservatively
answers MayAlias. When we properly take @g3 into account with the new
select logic, we get NoAlias for this query.

I suspect that the aforementioned "special logic" isn't completely
correct, but this test-case should prevent future wonky aliasing results
from appearing for these flavors of ConstantExprs, so I think it's still
worth having.

llvm-svn: 332017
2018-05-10 18:37:54 +00:00
Serguei Katkov
1e6b29ad19 [SCEV] Add missed Test for rL331949.
llvm-svn: 331950
2018-05-10 01:42:59 +00:00
Adhemerval Zanella
2e1b0642c7 [AArch64] Improve cost of vector division by constant
With custom lowering for vector MULLH{S,U}, it is now profitable to
vectorize a divide by constant loop for the custom types (v16i8, v8i16,
and v4i32).  The cost if based on TargetLowering::Build{S,U}DIV which
uses a multiply by constant plus adjustment to express a divide by
constant.

Both {u,s}mull{2} are expressed as Instruction::Mul and shifts by
Instruction::AShr.

llvm-svn: 331873
2018-05-09 12:48:22 +00:00
Simon Pilgrim
5046fae99f [CostModel][X86] Split off SLM checks
A future patch will require this and the diff is much better if we perform the split separately.

llvm-svn: 331867
2018-05-09 11:42:34 +00:00
Shiva Chen
a2029fa58e [DebugInfo] Add DILabel metadata and intrinsic llvm.dbg.label.
In order to set breakpoints on labels and list source code around
labels, we need collect debug information for labels, i.e., label
name, the function label belong, line number in the file, and the
address label located. In order to keep these information in LLVM
IR and to allow backend to generate debug information correctly.
We create a new kind of metadata for labels, DILabel. The format
of DILabel is

!DILabel(scope: !1, name: "foo", file: !2, line: 3)

We hope to keep debug information as much as possible even the
code is optimized. So, we create a new kind of intrinsic for label
metadata to avoid the metadata is eliminated with basic block.
The intrinsic will keep existing if we keep it from optimized out.
The format of the intrinsic is

llvm.dbg.label(metadata !1)

It has only one argument, that is the DILabel metadata. The
intrinsic will follow the label immediately. Backend could get the
label metadata through the intrinsic's parameter.

We also create DIBuilder API for labels to be used by Frontend.
Frontend could use createLabel() to allocate DILabel objects, and use
insertLabel() to insert llvm.dbg.label intrinsic in LLVM IR.

Differential Revision: https://reviews.llvm.org/D45024

Patch by Hsiangkai Wang.

llvm-svn: 331841
2018-05-09 02:40:45 +00:00
Piotr Padlewski
1e96fe1a21 Rename invariant.group.barrier to launder.invariant.group
Summary:
This is one of the initial commit of "RFC: Devirtualization v2" proposal:
https://docs.google.com/document/d/16GVtCpzK8sIHNc2qZz6RN8amICNBtvjWUod2SujZVEo/edit?usp=sharing

Reviewers: rsmith, amharc, kuhar, sanjoy

Subscribers: arsenm, nhaehnle, javed.absar, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D45111

llvm-svn: 331448
2018-05-03 11:03:01 +00:00