Commit Graph

21568 Commits

Author SHA1 Message Date
Nikita Popov 09020ec2a7 [InstCombine] Handle usubo always overflow
Check AlwaysOverflow condition for usubo. The implementation is the
same as the existing handling for uaddo and umulo. Handling for saddo
and ssubo will follow (smulo doesn't have the necessary ValueTracking
support).

Differential Revision: https://reviews.llvm.org/D60483

llvm-svn: 358052
2019-04-10 07:10:53 +00:00
Nikita Popov 596cbeb705 [InstCombine] Directly call computeOverflow methods in OptimizeOverflowCheck; NFC
Instead of using the willOverflow helpers. This makes it easier to
extend handling of AlwaysOverflows.

llvm-svn: 358051
2019-04-10 07:10:44 +00:00
Chen Zheng 5e13ff1da2 [InstCombine] Canonicalize (-X s/ Y) to -(X s/ Y).
Differential Revision: https://reviews.llvm.org/D60395

llvm-svn: 358050
2019-04-10 06:52:09 +00:00
Akira Hatanaka 9ca9d32b6b [ObjC][ARC] Convert the retainRV marker that is passed as a named
metadata into a module flag in the auto-upgrader and make the ARC
contract pass read the marker as a module flag.

This is needed to fix a bug where ARC contract wasn't inserting the
retainRV marker when LTO was enabled, which caused objects returned
from a function to be auto-released.

rdar://problem/49464214

Differential Revision: https://reviews.llvm.org/D60303

llvm-svn: 358047
2019-04-10 06:20:20 +00:00
Nikita Popov 2f5e9de8d1 Revert "[InstCombine] [InstCombine] Canonicalize (-X s/ Y) to -(X s/ Y)."
This reverts commit 1383a91689.

sdiv-canonicalize.ll fails after this revision. The fold needs to be
moved outside the branch handling constant operands. However when this
is done there are further test changes, so I'm reverting this in the
meantime.

llvm-svn: 358026
2019-04-09 18:32:38 +00:00
Nikita Popov eda3b9326e [InstCombine] Restructure OptimizeOverflowCheck; NFC
Change the code to always handle the unsigned+signed cases together
with the same basic structure for add/sub/mul. The simple folds are
always handled first and then the ValueTracking overflow checks are
used.

llvm-svn: 358025
2019-04-09 18:32:28 +00:00
Chen Zheng 1383a91689 [InstCombine] [InstCombine] Canonicalize (-X s/ Y) to -(X s/ Y).
Differential Revision: https://reviews.llvm.org/D60395

llvm-svn: 358017
2019-04-09 16:34:31 +00:00
Sanjay Patel 49d9d17a77 [InstCombine] prevent possible miscompile with sdiv+negate of vector op
Similar to:
rL358005

Forego folding arbitrary vector constants to fix a possible miscompile bug.
We can enhance the transform if we do want to handle the more complicated
vector case.

llvm-svn: 358013
2019-04-09 15:13:03 +00:00
Sanjay Patel f62dcea7ed [InstCombine] prevent possible miscompile with negate+sdiv of vector op
// 0 - (X sdiv C)  -> (X sdiv -C)  provided the negation doesn't overflow.

This fold has been around for many years and nobody noticed the potential
vector miscompile from overflow until recently...
So it seems unlikely that there's much demand for a vector sdiv optimization
on arbitrary vector constants, so just limit the matching to splat constants
to avoid the possible bug.

Differential Revision: https://reviews.llvm.org/D60426

llvm-svn: 358005
2019-04-09 14:09:06 +00:00
Peter Collingbourne df57979ba7 hwasan: Enable -hwasan-allow-ifunc by default.
It's been on in Android for a while without causing problems, so it's time
to make it the default and remove the flag.

Differential Revision: https://reviews.llvm.org/D60355

llvm-svn: 357960
2019-04-09 00:25:59 +00:00
Sanjay Patel 773e04c883 [InstCombine] peek through fdiv to find a squared sqrt
A more general canonicalization between fdiv and fmul would not
handle this case because that would have to be limited by uses
to prevent 2 values from becoming 3 values:
(x/y) * (x/y) --> (x*x) / (y*y)

(But we probably should still have that limited -- but more general --
canonicalization independently of this change.)

llvm-svn: 357943
2019-04-08 21:23:50 +00:00
Brian M. Rzycki 887865c1ad [JumpThreading] Fix incorrect fold conditional after indirectbr/callbr
Fixes bug 40992: https://bugs.llvm.org/show_bug.cgi?id=40992

There is potential for miscompiled code emitted from JumpThreading when
analyzing a block with one or more indirectbr or callbr predecessors. The
ProcessThreadableEdges() function incorrectly folds conditional branches
into an unconditional branch.

This patch prevents incorrect branch folding without fully pessimizing
other potential threading opportunities through the same basic block.

This IR shape was manually fed in via opt and is unclear if clang and the
full pass pipeline will ever emit similar code shapes.

Thanks to Matthias Liedtke for the bug report and simplified IR example.

Differential Revision: https://reviews.llvm.org/D60284

llvm-svn: 357930
2019-04-08 18:20:35 +00:00
Sanjay Patel b33938df7a [InstCombine] remove overzealous assert for shuffles (PR41419)
As the TODO indicates, instsimplify could be improved.

Should fix:
https://bugs.llvm.org/show_bug.cgi?id=41419

llvm-svn: 357910
2019-04-08 13:28:29 +00:00
Simon Pilgrim b4f1bfa659 [InstCombine][X86] Expand MOVMSK to generic IR (PR39927)
First step towards removing the MOVMSK intrinsics completely - this patch expands MOVMSK to the pattern:

e.g. PMOVMSKB(v16i8 x):
%cmp = icmp slt <16 x i8> %x, zeroinitializer
%int = bitcast <16 x i8> %cmp to i16
%res = zext i16 %int to i32

Which is correctly handled by ISel and FastIsel (give or take an annoying movzx move....): https://godbolt.org/z/rkrSFW

Differential Revision: https://reviews.llvm.org/D60256

llvm-svn: 357909
2019-04-08 13:17:51 +00:00
Chen Zheng 923c7c9daa [InstCombine] sdiv exact flag fixup.
Differential Revision: https://reviews.llvm.org/D60396

llvm-svn: 357904
2019-04-08 12:08:03 +00:00
Fangrui Song 2c5c12c041 Change some dyn_cast to more apropriate isa. NFC
llvm-svn: 357773
2019-04-05 16:16:23 +00:00
Evandro Menezes 85bd3978ae [IR] Refactor attribute methods in Function class (NFC)
Rename the functions that query the optimization kind attributes.

Differential revision: https://reviews.llvm.org/D60287

llvm-svn: 357731
2019-04-04 22:40:06 +00:00
Luqman Aden 8911c5be46 [InstCombine] Combine no-wrap sub and icmp w/ constant.
Teach InstCombine the transformation `(icmp P (sub nuw|nsw C2, Y), C) -> (icmp swap(P) Y, C2-C)`

Reviewers: majnemer, apilipenko, sanjoy, spatel, lebedev.ri

Reviewed By: lebedev.ri

Subscribers: dmgreen, lebedev.ri, nikic, hiraditya, JDevlieghere, jfb, jdoerfert, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D59916

llvm-svn: 357674
2019-04-04 07:08:30 +00:00
David L. Jones 8b8a02175a Revert r357452 - 'SimplifyCFG SinkCommonCodeFromPredecessors: Also sink function calls without used results (PR41259)'
This revision causes tests to fail under ASAN. Since the cause of the failures
is not clear (could be ASAN, could be a Clang bug, could be a bug in this
revision), the safest course of action seems to be to revert while investigating.

llvm-svn: 357667
2019-04-04 02:27:57 +00:00
Evandro Menezes 7c711ccf36 [IR] Create new method in `Function` class (NFC)
Create method `optForNone()` testing for the function level equivalent of
`-O0` and refactor appropriately.

Differential revision: https://reviews.llvm.org/D59852

llvm-svn: 357638
2019-04-03 21:27:03 +00:00
David Bolvansky 937720e75b [InstCombine] Simplify ctpop with bitreverse/bswap
Summary: Fixes PR41337

Reviewers: spatel

Reviewed By: spatel

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60148

llvm-svn: 357564
2019-04-03 08:08:44 +00:00
Alon Zakai b4f9991f38 [WebAssembly] Add Emscripten OS definition + small_printf
The Emscripten OS provides a definition of __EMSCRIPTEN__, and also that it
supports iprintf optimizations.

Also define small_printf optimizations, which is a printf with float support
but not long double (which in wasm can be useful since long doubles are 128
bit and force linking of float128 emulation code). This part is based on
sunfish's https://reviews.llvm.org/D57620 (which can't land yet since
the WASI integration isn't ready yet).

Differential Revision: https://reviews.llvm.org/D60167

llvm-svn: 357552
2019-04-03 01:08:35 +00:00
David Bolvansky 5ba60b22a4 [InstCombine] Simplify ctlz/cttz with bitreverse
Summary: Fixes PR41273

Reviewers: spatel

Reviewed By: spatel

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60096

llvm-svn: 357521
2019-04-02 20:13:28 +00:00
Vedant Kumar 9da8a68d6b [ArgPromotion] Set debug location at updated callsites
Set the correct debug location on instructions which load arguments in
preparation for a call to an arg-promoted function.

This prevents location cascade from misattributing the line/scope of one
of these loads to the location of the instruction preceding the call.

Differential Revision: https://reviews.llvm.org/D60113

llvm-svn: 357500
2019-04-02 17:42:17 +00:00
Vedant Kumar c6bceec01a [DebugInfo] Fix pr41180 : Loop Vectorization Debugify Failure
Bug: https://bugs.llvm.org/show_bug.cgi?id=41180

In the bug test case the debug location was missing for the cmp instruction in
the "middle block" BB. This patch fixes the bug by copying the debug location
from the cmp of the scalar loop's terminator branch, if it exists.

The patch also fixes the debug location on the subsequent branch instruction.
It was previously using the location of the of the original loop's pre-header
block terminator. Both of these instructions will now map to the source line of
the conditional branch in the original loop.

A regression test has been added that covers these issues.

Patch by Orlando Cazalet-Hyams!

Differential Revision: https://reviews.llvm.org/D59944

llvm-svn: 357499
2019-04-02 17:28:34 +00:00
Simon Pilgrim a3b71018d9 [SLP] reorderInputsAccordingToOpcode is const method. NFCI.
llvm-svn: 357490
2019-04-02 16:27:11 +00:00
Joseph Tremoulet fb4d9f7287 [SimplifyCFG] Don't split musttail call from ret
Summary:
When inserting an `unreachable` after a noreturn call, we must ensure
that it's not a musttail call to avoid breaking the IR invariants for
musttail calls.

Reviewers: fedor.sergeev, majnemer

Reviewed By: majnemer

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60080

llvm-svn: 357485
2019-04-02 15:48:58 +00:00
Taewook Oh 6a27c48be2 [SampleProfile] Repeat indirect call promotion only when the target is actually hot.
Summary: It is possible that multiple indirect call targets have been promoted for a single callsite from the profiled binary. Current implementation repeats promotion for all these targets as far as the callsite itself is hot (the callsite is assumed to be hot if any one of these targets was "hot" during the profiling). However, even when one of the ICPed target is hot other targets may not, and we should not repeat promotion for "cold" targets.

Reviewers: danielcdh, wmi

Subscribers: hiraditya, jdoerfert, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D59940

llvm-svn: 357484
2019-04-02 15:48:21 +00:00
Joseph Tremoulet b69afa8e9b [PruneEH] Don't split musttail call from ret
Summary:
When inserting an `unreachable` after a noreturn call, we must ensure
that it's not a musttail call to avoid breaking the IR invariants for
musttail calls.

Reviewers: fedor.sergeev, majnemer

Reviewed By: majnemer

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60079

llvm-svn: 357483
2019-04-02 15:47:11 +00:00
Brian Gesiak 1c44ed8b76 [Transforms] Redundant getValueOperand (NFC)
`StoreInst::getValueOperand` is identical to `getOperand(0)`, so the call to
`getOperand(0)` can be replaced. Further, `SI->getValueOperand` is redundantly
called just a few lines down, despite its return value being stored in variable
`DV`. No functional change.

llvm-svn: 357479
2019-04-02 14:57:56 +00:00
Fangrui Song f421978858 [Internalize] Replace uses of std::set with DenseSet
This makes it faster and saves 104 bytes for my build.

llvm-svn: 357458
2019-04-02 09:25:31 +00:00
Fangrui Song 32029135e0 [Internalize] Replace fstream with line_iterator for -internalize-public-api-file
This makes my libLLVMipo.so.9svn smaller by 360 bytes.

llvm-svn: 357457
2019-04-02 09:11:18 +00:00
Hans Wennborg b669fea42f SimplifyCFG SinkCommonCodeFromPredecessors: Also sink function calls without used results (PR41259)
The code was previously checking that candidates for sinking had exactly
one use or were a store instruction (which can't have uses). This meant
we could sink call instructions only if they had a use.

That limitation seemed a bit arbitrary, so this patch changes it to
"instruction has zero or one use" which seems more natural and removes
the need to special-case stores.

Differential revision: https://reviews.llvm.org/D59936

llvm-svn: 357452
2019-04-02 08:01:38 +00:00
Philip Reames adb3ece216 [LoopPredication] Simplify widenable condition handling [NFC]
The code doesn't actually need any of the information about the widenable condition at this level.  The only thing we need is to ensure the WC call is the last thing anded in, and even that is a quirk we should really look to remove.

llvm-svn: 357448
2019-04-02 02:42:57 +00:00
Philip Reames f608678f1f [LoopPred] Rename a variable to simply a future patch [NFC]
llvm-svn: 357433
2019-04-01 22:39:54 +00:00
Nick Lewycky 1e1e212d27 [NFC] Remove dead parameter "FreeInLoop", fix some typos and trailing whitespace.
Differential Revision: https://reviews.llvm.org/D60084

llvm-svn: 357427
2019-04-01 20:37:56 +00:00
Simon Pilgrim b06935fa8c [SLP] getVectorElementSize and isTreeTinyAndNotFullyVectorizable are const methods. NFCI.
llvm-svn: 357416
2019-04-01 17:48:03 +00:00
Simon Pilgrim f6c04ad486 [SLP] getGatherCost and isFullyVectorizableTinyTree are const methods. NFCI.
llvm-svn: 357414
2019-04-01 17:32:46 +00:00
Philip Reames 05e3e554b4 [LoopPred] Be uniform about proving generated conditions
We'd been optimizing the case where the predicate was obviously true, do the same for the false case.  Mostly just for completeness sake, but also may improve compile time in loops which will exit through the guard.  Such loops are presumed rare in fastpath code, but may be present down untaken paths, so optimizing for them is still useful.

llvm-svn: 357408
2019-04-01 16:26:08 +00:00
Philip Reames d109e2a7c3 [LoopPred] Delete the old condition expressions if unused
LoopPredication was replacing the original condition, but leaving the instructions to compute the old conditions around.  This would get cleaned up by other passes of course, but we might as well do it eagerly.  That also makes the test output less confusing.  

llvm-svn: 357406
2019-04-01 16:05:15 +00:00
Mikael Holmen 150a7ec2dc [InstCombine] Handle vector gep with scalar argument in evaluateInDifferentElementOrder
Summary:
This fixes PR41270.

The recursive function evaluateInDifferentElementOrder expects to be called
on a vector Value, so when we call it on a vector GEP's arguments, we must
first check that the argument is indeed a vector.

Reviewers: reames, spatel

Reviewed By: spatel

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60058

llvm-svn: 357389
2019-04-01 14:10:10 +00:00
Mikael Holmen 3e527cd823 Revert "[InstCombine] Handle vector gep with scalar argument in evaluateInDifferentElementOrder"
This reverts commit 75216a6dbcfe5fb55039ef06a07e419fa875f4a5.

I'll recommit with a better commit message with reference to the
phabricator review.

llvm-svn: 357387
2019-04-01 14:06:45 +00:00
Mikael Holmen d66a47f90a [InstCombine] Handle vector gep with scalar argument in evaluateInDifferentElementOrder
This fixes PR41270.

The recursive function evaluateInDifferentElementOrder expects to be called
on a vector Value, so when we call it on a vector GEP's arguments, we must
first check that the argument is indeed a vector.

llvm-svn: 357385
2019-04-01 13:48:56 +00:00
Sanjay Patel 97d1bc4454 [InstCombine] eliminate commuted select-shuffles + binop (PR41304)
If we have a commutable vector binop with inverted select-shuffles,
we don't care about the order of the operands in each vector lane:

LHS = shuffle V1, V2, <0, 5, 6, 3>
RHS = shuffle V2, V1, <0, 5, 6, 3>
LHS + RHS --> <V1[0]+V2[0], V2[1]+V1[1], V2[2]+V1[2], V1[3]+V2[3]> --> V1 + V2

PR41304:
https://bugs.llvm.org/show_bug.cgi?id=41304
...is currently titled as an SLP enhancement, but at least for the
given example, we can reduce that in instcombine because we are just
eliminating shuffles.

As noted in the TODO, this could be generalized, but I haven't thought
through those patterns completely, so this is limited to what appears
to be always safe.

Differential Revision: https://reviews.llvm.org/D60048

llvm-svn: 357382
2019-04-01 13:36:40 +00:00
Sanjay Patel b276dd195a [InstCombine] canonicalize select shuffles by commuting
In PR41304:
https://bugs.llvm.org/show_bug.cgi?id=41304
...we have a case where we want to fold a binop of select-shuffle (blended) values.

Rather than try to match commuted variants of the pattern, we can canonicalize the
shuffles and check for mask equality with commuted operands.

We don't produce arbitrary shuffle masks in instcombine, but select-shuffles are a
special case that the backend is required to handle because we already canonicalize
vector select to this shuffle form.

So there should be no codegen difference from this change. It's possible that this
improves CSE in IR though.

Differential Revision: https://reviews.llvm.org/D60016

llvm-svn: 357366
2019-03-31 15:01:30 +00:00
Philip Reames b55637b5d7 [LoopPredication] Remove stale TODO
llvm-svn: 357331
2019-03-29 23:10:01 +00:00
Philip Reames 3d4e108237 [LoopPredication] Use the builder's insertion point everywhere [NFC]
llvm-svn: 357330
2019-03-29 23:06:57 +00:00
Sanjay Patel 3f4d1b4abd [InstCombine] move shuffle canonicalizations before other transforms
This may not be NFC, but I'm not sure how to expose any diffs in
tests. In theory, it should be slightly more efficient and possibly
more profitable to do the canonicalizations (which can increase the
undef elements in the mask) ahead of SimplifyDemandedVectorElts().

llvm-svn: 357272
2019-03-29 16:49:38 +00:00
Simon Pilgrim 6a75c36ea9 [SLP] Add support for commutative icmp/fcmp predicates
For the cases where the icmp/fcmp predicate is commutative, use reorderInputsAccordingToOpcode to collect and commute the operands.

This requires a helper to recognise commutativity in both general Instruction and CmpInstr types - the CmpInst::isCommutative doesn't overload the Instruction::isCommutative method for reasons I'm not clear on (maybe because its based on predicate not opcode?!?).

Differential Revision: https://reviews.llvm.org/D59992

llvm-svn: 357266
2019-03-29 15:28:25 +00:00
Florian Hahn 9b41a7320d Recommit "[DSE] Preserve basic block ordering using OrderedBasicBlock."
Updated to use DenseMap::insert instead of [] operator for insertion, to
avoid a crash caused by epoch checks.

This reverts commit 2b85de4383.

llvm-svn: 357257
2019-03-29 14:10:24 +00:00
Simon Pilgrim 62f0d1650a [SLP] Add support for swapping icmp/fcmp predicates to permit vectorization
We should be able to match elements with the swapped predicate as well - as long as we commute the source operands.

Differential Revision: https://reviews.llvm.org/D59956

llvm-svn: 357243
2019-03-29 10:41:00 +00:00
Florian Hahn 2b85de4383 Revert Recommit "[DSE] Preserve basic block ordering using OrderedBasicBlock."
Another buildbot failure

http://lab.llvm.org:8011/builders/clang-cmake-x86_64-sde-avx512-linux/builds/20402

clang-9: /home/ssglocal/clang-cmake-x86_64-sde-avx512-linux/clang-cmake-x86_64-sde-avx512-linux/llvm/include/llvm/ADT/DenseMap.h:1228: llvm::DenseMapIterator<KeyT, ValueT, KeyInfoT, Bucket, IsConst>::value_type* llvm::DenseMapIterator<KeyT, ValueT, KeyInfoT, Bucket, IsConst>::operator->() const [with KeyT = const llvm::Instruction*; ValueT = unsigned int; KeyInfoT = llvm::DenseMapInfo<const llvm::Instruction*>; Bucket = llvm::detail::DenseMapPair<const llvm::Instruction*, unsigned int>; bool IsConst = false; llvm::DenseMapIterator<KeyT, ValueT, KeyInfoT, Bucket, IsConst>::pointer = llvm::detail::DenseMapPair<const llvm::Instruction*, unsigned int>*; llvm::DenseMapIterator<KeyT, ValueT, KeyInfoT, Bucket, IsConst>::value_type = llvm::detail::DenseMapPair<const llvm::Instruction*, unsigned int>]: Assertion `isHandleInSync() && "invalid iterator access!"' failed.

0.	Program arguments: /home/ssglocal/clang-cmake-x86_64-sde-avx512-linux/clang-cmake-x86_64-sde-avx512-linux/stage1.install/bin/clang-9 -cc1 -triple x86_64-unknown-linux-gnu -emit-obj -disable-free -main-file-name ArchiveCommandLine.cpp -mrelocation-model static -mthread-model posix -fmath-errno -masm-verbose -mconstructor-aliases -munwind-tables -fuse-init-array -target-cpu skylake-avx512 -dwarf-column-info -debugger-tuning=gdb -momit-leaf-frame-pointer -coverage-notes-file /home/ssglocal/clang-cmake-x86_64-sde-avx512-linux/clang-cmake-x86_64-sde-avx512-linux/test/sandbox/build/MultiSource/Benchmarks/7zip/Output/ArchiveCommandLine.llvm.gcno -resource-dir /home/ssglocal/clang-cmake-x86_64-sde-avx512-linux/clang-cmake-x86_64-sde-avx512-linux/stage1.install/lib/clang/9.0.0 -I /home/ssglocal/clang-cmake-x86_64-sde-avx512-linux/clang-cmake-x86_64-sde-avx512-linux/test/sandbox/build/MultiSource/Benchmarks/7zip -I /home/ssglocal/clang-cmake-x86_64-sde-avx512-linux/clang-cmake-x86_64-sde-avx512-linux/test/test-suite/MultiSource/Benchmarks/7zip -I /home/ssglocal/clang-cmake-x86_64-sde-avx512-linux/clang-cmake-x86_64-sde-avx512-linux/test/test-suite/include -I ../../../include -D _GNU_SOURCE -D __STDC_LIMIT_MACROS -D NDEBUG -D BREAK_HANDLER -D UNICODE -D _UNICODE -I /home/ssglocal/clang-cmake-x86_64-sde-avx512-linux/clang-cmake-x86_64-sde-avx512-linux/test/test-suite/MultiSource/Benchmarks/7zip/C -I /home/ssglocal/clang-cmake-x86_64-sde-avx512-linux/clang-cmake-x86_64-sde-avx512-linux/test/test-suite/MultiSource/Benchmarks/7zip/CPP/myWindows -I /home/ssglocal/clang-cmake-x86_64-sde-avx512-linux/clang-cmake-x86_64-sde-avx512-linux/test/test-suite/MultiSource/Benchmarks/7zip/CPP/include_windows -I /home/ssglocal/clang-cmake-x86_64-sde-avx512-linux/clang-cmake-x86_64-sde-avx512-linux/test/test-suite/MultiSource/Benchmarks/7zip/CPP -I . -D _FILE_OFFSET_BITS=64 -D _LARGEFILE_SOURCE -D NDEBUG -D _REENTRANT -D ENV_UNIX -D _7ZIP_LARGE_PAGES -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/5.4.0/../../../../include/c++/5.4.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/5.4.0/../../../../include/x86_64-linux-gnu/c++/5.4.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/5.4.0/../../../../include/x86_64-linux-gnu/c++/5.4.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/5.4.0/../../../../include/c++/5.4.0/backward -internal-isystem /usr/local/include -internal-isystem /home/ssglocal/clang-cmake-x86_64-sde-avx512-linux/clang-cmake-x86_64-sde-avx512-linux/stage1.install/lib/clang/9.0.0/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O3 -std=gnu++98 -fdeprecated-macro -fdebug-compilation-dir /home/ssglocal/clang-cmake-x86_64-sde-avx512-linux/clang-cmake-x86_64-sde-avx512-linux/test/sandbox/build/MultiSource/Benchmarks/7zip -ferror-limit 19 -fmessage-length 0 -pthread -fobjc-runtime=gcc -fcxx-exceptions -fexceptions -fdiagnostics-show-option -vectorize-loops -vectorize-slp -o Output/ArchiveCommandLine.llvm.o -x c++ /home/ssglocal/clang-cmake-x86_64-sde-avx512-linux/clang-cmake-x86_64-sde-avx512-linux/test/test-suite/MultiSource/Benchmarks/7zip/CPP/7zip/UI/Common/ArchiveCommandLine.cpp -faddrsig

This reverts r357222 (git commit 64cccfcc72)

llvm-svn: 357227
2019-03-29 00:22:26 +00:00
Florian Hahn 64cccfcc72 Recommit "[DSE] Preserve basic block ordering using OrderedBasicBlock."
Recommitting after addressing a buildbot failure.

This reverts commit c87869ebea.

llvm-svn: 357222
2019-03-28 23:11:00 +00:00
Florian Hahn 45682fd633 [LSR] Fix signed overflow in GenerateCrossUseConstantOffsets.
For the attached test case, unchecked addition of immediate starts and
ends overflows, as they can be arbitrary i64 constants.

Proof: https://rise4fun.com/Alive/Plqc

Reviewers: qcolombet, gilr, efriedma

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D59218

llvm-svn: 357217
2019-03-28 22:17:29 +00:00
Florian Hahn c87869ebea Revert [DSE] Preserve basic block ordering using OrderedBasicBlock.
This reverts r357208 (git commit c0bfd37d38)

This causes a buildbot failure:  http://lab.llvm.org:8011/builders/clang-with-thin-lto-ubuntu/builds/16124

FAILED: lib/IR/CMakeFiles/LLVMCore.dir/IRBuilder.cpp.o
/home/buildslave/ps4-buildslave1/clang-with-thin-lto-ubuntu/install/stage2/bin/clang++   -DGTEST_HAS_RTTI=0 -D_DEBUG -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -Ilib/IR -I/home/buildslave/ps4-buildslave1/clang-with-thin-lto-ubuntu/llvm.src/lib/IR -Iinclude -I/home/buildslave/ps4-buildslave1/clang-with-thin-lto-ubuntu/llvm.src/include -fPIC -fvisibility-inlines-hidden -Werror -Werror=date-time -Werror=unguarded-availability-new -std=c++11 -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -pedantic -Wno-long-long -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wstring-conversion -fdiagnostics-color -ffunction-sections -fdata-sections -flto=thin -O3    -UNDEBUG  -fno-exceptions -fno-rtti -MD -MT lib/IR/CMakeFiles/LLVMCore.dir/IRBuilder.cpp.o -MF lib/IR/CMakeFiles/LLVMCore.dir/IRBuilder.cpp.o.d -o lib/IR/CMakeFiles/LLVMCore.dir/IRBuilder.cpp.o -c /home/buildslave/ps4-buildslave1/clang-with-thin-lto-ubuntu/llvm.src/lib/IR/IRBuilder.cpp
clang-9: /home/buildslave/ps4-buildslave1/clang-with-thin-lto-ubuntu/llvm.src/lib/Analysis/OrderedBasicBlock.cpp:38: bool llvm::OrderedBasicBlock::comesBefore(const llvm::Instruction *, const llvm::Instruction *): Assertion `!(LastInstFound == BB->end() && NextInstPos != 0) && "Instruction supposed to be in NumberedInsts"' failed.

llvm-svn: 357211
2019-03-28 20:36:24 +00:00
Florian Hahn c0bfd37d38 [DSE] Preserve basic block ordering using OrderedBasicBlock.
By extending OrderedBB to allow removing and replacing cached
instructions, we can preserve OrderedBBs in DSE easily. This eliminates
one source of quadratic compile time in DSE.

Fixes PR38829.

Reviewers: rnk, efriedma, hfinkel

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D59789

llvm-svn: 357208
2019-03-28 20:02:33 +00:00
Benjamin Kramer ba2ea93ad1 Make helper functions static. NFC.
llvm-svn: 357187
2019-03-28 17:18:42 +00:00
Pierre Gousseau a833c2bd3e [asan] Add options -asan-detect-invalid-pointer-cmp and -asan-detect-invalid-pointer-sub options.
This is in preparation to a driver patch to add gcc 8's -fsanitize=pointer-compare and -fsanitize=pointer-subtract.
Disabled by default as this is still an experimental feature.

Reviewed By: morehouse, vitalybuka

Differential Revision: https://reviews.llvm.org/D59220

llvm-svn: 357157
2019-03-28 10:51:24 +00:00
Florian Hahn e21ed594d8 [VPlan] Determine Vector Width programmatically.
With this change, the VPlan native path is triggered with the directive:

   #pragma clang loop vectorize(enable)

There is no need to specify the vectorize_width(N) clause.

Patch by Francesco Petrogalli <francesco.petrogalli@arm.com>

Differential Revision: https://reviews.llvm.org/D57598

llvm-svn: 357156
2019-03-28 10:37:12 +00:00
Nikita Popov 7462303e06 [InstCombine] Use uadd.sat and usub.sat for canonicalization
Start using the uadd.sat and usub.sat intrinsics for the existing
canonicalizations. These intrinsics should optimize better than
expanded IR, have better handling in the X86 backend and should
be no worse than expanded IR in other backends, as far as we know.

rL357012 already introduced use of uadd.sat for the add+umin pattern.

Differential Revision: https://reviews.llvm.org/D58872

llvm-svn: 357103
2019-03-27 17:56:15 +00:00
Sanjay Patel 81e8d76f5b [InstCombine] form uaddsat from add+umin (PR14613)
This is the last step towards solving the examples shown in:
https://bugs.llvm.org/show_bug.cgi?id=14613

With this change, x86 should end up with psubus instructions
when those are available.

All known codegen issues with expanding the saturating intrinsics
were resolved with:
D59006 / rL356855

We also have some early evidence in D58872 that using the intrinsics
will lead to better perf. If some target regresses from this, custom
lowering of the intrinsics (as in the above for x86) may be needed.

llvm-svn: 357012
2019-03-26 17:50:08 +00:00
Simon Pilgrim 6f96795b88 [SLPVectorizer] Merge reorderAltShuffleOperands into reorderInputsAccordingToOpcode
As discussed on D59738, this generalizes reorderInputsAccordingToOpcode to handle multiple + non-commutative instructions so we can get rid of reorderAltShuffleOperands and make use of the extra canonicalizations that reorderInputsAccordingToOpcode brings.

Differential Revision: https://reviews.llvm.org/D59784

llvm-svn: 356939
2019-03-25 20:05:27 +00:00
Simon Pilgrim ff3abef395 [SLPVectorizer] reorderInputsAccordingToOpcode - remove non-Instruction canonicalization
Remove attempts to commute non-Instructions to the LHS - the codegen changes appear to rely on chance more than anything else and also have a tendency to fight existing instcombine canonicalization which moves constants to the RHS of commutable binary ops.

This is prep work towards:
(a) reusing reorderInputsAccordingToOpcode for alt-shuffles and removing the similar reorderAltShuffleOperands
(b) improving reordering to optimized cases with commutable and non-commutable instructions to still find splat/consecutive ops.

Differential Revision: https://reviews.llvm.org/D59738

llvm-svn: 356913
2019-03-25 15:53:55 +00:00
Simon Pilgrim 5cd4eb96f6 [SLPVectorizer] shouldReorderOperands - just check for reordering. NFCI.
Remove the I.getOperand() calls from inside shouldReorderOperands - reorderInputsAccordingToOpcode should handle the creation of the operand lists and shouldReorderOperands should just check to see whether the i'th element should be commuted.

llvm-svn: 356854
2019-03-24 13:36:32 +00:00
Nikita Popov 977934f00f [ConstantRange] Add getFull() + getEmpty() named constructors; NFC
This adds ConstantRange::getFull(BitWidth) and
ConstantRange::getEmpty(BitWidth) named constructors as more readable
alternatives to the current ConstantRange(BitWidth, /* full */ false)
and similar. Additionally private getFull() and getEmpty() member
functions are added which return a full/empty range with the same bit
width -- these are commonly needed inside ConstantRange.cpp.

The IsFullSet argument in the ConstantRange(BitWidth, IsFullSet)
constructor is now mandatory for the few usages that still make use of it.

Differential Revision: https://reviews.llvm.org/D59716

llvm-svn: 356852
2019-03-24 09:34:40 +00:00
Simon Pilgrim 1466e5c383 Fix unused variable warning on non-asserts builds. NFCI.
llvm-svn: 356841
2019-03-23 16:56:23 +00:00
Simon Pilgrim 64feec7977 Remove unused function argument. NFCI.
llvm-svn: 356840
2019-03-23 16:20:34 +00:00
Simon Pilgrim c7ba9555cf [SLPVectorizer] reorderInputsAccordingToOpcode - use InstructionState directly. NFCI.
llvm-svn: 356832
2019-03-23 13:44:06 +00:00
Nikita Popov 0125e4484e [LowerSwitch] Use ConstantRange::fromKnownBits(); NFC
Using an unsigned range to stay NFC, but a signed range would really
be more useful here.

llvm-svn: 356831
2019-03-23 12:48:54 +00:00
Simon Pilgrim f4f01f3cff [SLPVectorizer] Don't repeat VL.size() call. NFCI.
llvm-svn: 356830
2019-03-23 12:11:25 +00:00
Simon Pilgrim b68322f9d0 [SLP] Remove redundancy of performing operand reordering twice: once in buildTree() and later in vectorizeTree().
This is a refactoring patch that removes the redundancy of performing operand reordering twice, once in buildTree() and later in vectorizeTree().
To achieve this we need to keep track of the operands within the TreeEntry struct while building the tree, and later in vectorizeTree() we are just accessing them from the TreeEntry in the right order.

This patch is the first in a series of patches that will allow for better operand reordering across chains of instructions (e.g., a chain of ADDs), as presented here: https://www.youtube.com/watch?v=gIEn34LvyNo

Patch by: @vporpo (Vasileios Porpodas)

Differential Revision: https://reviews.llvm.org/D59059

llvm-svn: 356814
2019-03-22 21:27:11 +00:00
Daniel Sanders ef8761fd3b Fix non-determinism in Reassociate caused by address coincidences
Summary:
Between building the pair map and querying it there are a few places that
erase and create Values. It's rare but the address of these newly created
Values is occasionally the same as a just-erased Value that we already
have in the pair map. These coincidences should be accounted for to avoid
non-determinism.

Thanks to Roman Tereshin for the test case.

Reviewers: rtereshin, bogner

Reviewed By: rtereshin

Subscribers: mgrang, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D59401

llvm-svn: 356803
2019-03-22 20:16:35 +00:00
Tim Renouf 94c163c34e InstCombineSimplifyDemanded: Allow v3 results for AMDGCN buffer and image intrinsics
This helps to avoid the situation where RA spots that only 3 of the
v4f32 result of a load are used, and immediately reallocates the 4th
register for something else, requiring a stall waiting for the load.

Differential Revision: https://reviews.llvm.org/D58906

Change-Id: I947661edfd5715f62361a02b100f14aeeada29aa
llvm-svn: 356768
2019-03-22 15:53:50 +00:00
Akira Hatanaka b576c77a9e Don't add a tail keyword to calls to ObjC runtime functions if the calls
are annotated with notail.

r356705 annotated calls to objc_retainAutoreleasedReturnValue with
notail on x86-64. This commit teaches ARC optimizer to check the notail
marker on the call before turning it into a tail call.

rdar://problem/38675807

llvm-svn: 356707
2019-03-21 20:16:09 +00:00
Craig Topper 16dc165046 [InstCombine] Don't transform ((C1 OP zext(X)) & C2) -> zext((C1 OP X) & C2) if either zext or OP has another use.
If they have other users we'll just end up increasing the instruction count.

We might be able to weaken this to only one of them having a single use if we can prove that the and will be removed.

Fixes PR41164.

Differential Revision: https://reviews.llvm.org/D59630

llvm-svn: 356690
2019-03-21 17:50:49 +00:00
Simon Pilgrim 92cbcfc325 Fix -Wmisleading-indentation gcc7 warning. NFCI.
llvm-svn: 356658
2019-03-21 11:58:22 +00:00
Mikael Holmen 5b1754f93d Silence warning about unused variable in builds without asserts [NFC]
llvm-svn: 356648
2019-03-21 07:54:44 +00:00
Philip Reames 60212be619 [instcombine] Add some todos, and arrange code for readibility
llvm-svn: 356642
2019-03-21 03:23:40 +00:00
Alina Sbirlea f69f807321 [NFC] Fix brace indentation.
llvm-svn: 356596
2019-03-20 19:18:55 +00:00
Robert Lougher f2158a8ef0 Resubmit r356511 "[TailCallElim] Add tailcall elimination pass to LTO pipelines"
Failing LLD tests have been fixed in r356593.

llvm-svn: 356594
2019-03-20 19:08:18 +00:00
Philip Reames e4588bbf80 Simplify operands of masked stores and scatters based on demanded elements
If we know we're not storing a lane, we don't need to compute the lane. This could be improved by using the undef element result to further prune the mask, but I want to separate that into its own change since it's relatively likely to expose other problems.

Differential Revision: https://reviews.llvm.org/D57247

llvm-svn: 356590
2019-03-20 18:44:58 +00:00
Alina Sbirlea 5baa72ea74 [LICM & MemorySSA] Don't sink/hoist stores in the presence of ordered loads.
Summary:
Before this patch, if any Use existed in the loop, with a defining
access in the loop, we conservatively decide to not move the store.
What this approach was missing, is that ordered loads are not Uses, they're Defs
in MemorySSA. So, even when the clobbering walker does not find that
volatile load to interfere, we still cannot hoist a store past a
volatile load.
Resolves PR41140.

Reviewers: george.burgess.iv

Subscribers: sanjoy, jlebar, Prazek, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D59564

llvm-svn: 356588
2019-03-20 18:33:37 +00:00
Nikita Popov 37cf25c3c6 [InstCombine] Fold add nuw + uadd.with.overflow
Fold add nuw and uadd.with.overflow with constants if the
addition does not overflow.

Part of https://bugs.llvm.org/show_bug.cgi?id=38146.

Patch by Dan Robertson.

Differential Revision: https://reviews.llvm.org/D59471

llvm-svn: 356584
2019-03-20 18:00:27 +00:00
Philip Reames 484d07c828 [instcombine] Add todos describing missing transforms for masked.* intrinsics
llvm-svn: 356536
2019-03-20 03:36:05 +00:00
Robert Lougher c67a759c99 Revert r356511 "[TailCallElim] Add tailcall elimination pass to LTO pipelines"
Due to buildbot failures (LLD tests).

llvm-svn: 356516
2019-03-19 20:54:20 +00:00
Robert Lougher de548ccab9 [TailCallElim] Add tailcall elimination pass to LTO pipelines
LTO provides additional opportunities for tailcall elimination due to
link-time inlining and visibility of nocapture attribute. Testing showed
negligible impact on compilation times.

Differential Revision: https://reviews.llvm.org/D58391

llvm-svn: 356511
2019-03-19 20:24:28 +00:00
Philip Reames 70537abe52 Demanded elements support for masked.load and masked.gather
Teach instcombine to propagate demanded elements through a masked load or masked gather instruction. This is in the broader context of improving vector pointer instcombine under https://reviews.llvm.org/D57140.

Differential Revision: https://reviews.llvm.org/D57372

llvm-svn: 356510
2019-03-19 20:10:00 +00:00
Sanjay Patel 5b820323ca [InstCombine] fold logic-of-nan-fcmps (PR41069)
Combine 2 fcmps that are checking for nan-ness:
   and (fcmp ord X, 0), (and (fcmp ord Y, 0), Z) --> and (fcmp ord X, Y), Z
   or  (fcmp uno X, 0), (or  (fcmp uno Y, 0), Z) --> or  (fcmp uno X, Y), Z

This is an exact match for a minimal reassociation pattern.
If we want to handle this more generally that should go in
the reassociate pass and allow removing this code.

This should fix:
https://bugs.llvm.org/show_bug.cgi?id=41069

llvm-svn: 356471
2019-03-19 16:39:17 +00:00
Markus Lavin b86ce219f4 [DebugInfo] Introduce DW_OP_LLVM_convert
Introduce a DW_OP_LLVM_convert Dwarf expression pseudo op that allows
for a convenient way to perform type conversions on the Dwarf expression
stack. As an additional bonus it paves the way for using other Dwarf
v5 ops that need to reference a base_type.

The new DW_OP_LLVM_convert is used from lib/Transforms/Utils/Local.cpp
to perform sext/zext on debug values but mainly the patch is about
preparing terrain for adding other Dwarf v5 ops that need to reference a
base_type.

For Dwarf v5 the op maps to DW_OP_convert and for earlier versions a
complex shift & mask pattern is generated to emulate sext/zext.

This is a recommit of r356442 with trivial fixes for the failing tests.

Differential Revision: https://reviews.llvm.org/D56587

llvm-svn: 356451
2019-03-19 13:16:28 +00:00
Markus Lavin ad78768d59 Revert "[DebugInfo] Introduce DW_OP_LLVM_convert"
This reverts commit 1cf4b593a7ebd666fc6775f3bd38196e8e65fafe.

Build bots found failing tests not detected locally.

Failing Tests (3):
  LLVM :: DebugInfo/Generic/convert-debugloc.ll
  LLVM :: DebugInfo/Generic/convert-inlined.ll
  LLVM :: DebugInfo/Generic/convert-linked.ll

llvm-svn: 356444
2019-03-19 09:17:28 +00:00
Markus Lavin cd8a940b37 [DebugInfo] Introduce DW_OP_LLVM_convert
Introduce a DW_OP_LLVM_convert Dwarf expression pseudo op that allows
for a convenient way to perform type conversions on the Dwarf expression
stack. As an additional bonus it paves the way for using other Dwarf
v5 ops that need to reference a base_type.

The new DW_OP_LLVM_convert is used from lib/Transforms/Utils/Local.cpp
to perform sext/zext on debug values but mainly the patch is about
preparing terrain for adding other Dwarf v5 ops that need to reference a
base_type.

For Dwarf v5 the op maps to DW_OP_convert and for earlier versions a
complex shift & mask pattern is generated to emulate sext/zext.

Differential Revision: https://reviews.llvm.org/D56587

llvm-svn: 356442
2019-03-19 08:48:19 +00:00
Sanjay Patel 6063393536 [InstCombine] allow general vector constants for funnel shift to shift transforms
Follow-up to:
rL356338
rL356369

We can calculate an arbitrary vector constant minus the bitwidth, so there's
no need to limit this transform to scalars and splats.

llvm-svn: 356372
2019-03-18 14:27:51 +00:00
Sanjay Patel 84de8a30a0 [InstCombine] extend rotate-left-by-constant canonicalization to funnel shift
Follow-up to:
rL356338

Rotates are a special case of funnel shift where the 2 input operands
are the same value, but that does not need to be a restriction for the
canonicalization when the shift amount is a constant.

llvm-svn: 356369
2019-03-18 14:10:11 +00:00
Sanjay Patel b3bcd95771 [InstCombine] canonicalize rotate right by constant to rotate left
This was noted as a backend problem:
https://bugs.llvm.org/show_bug.cgi?id=41057
...and subsequently fixed for x86:
rL356121
But we should canonicalize these in IR for the benefit of all targets
and improve IR analysis such as CSE.

llvm-svn: 356338
2019-03-17 19:08:00 +00:00
Philip Reames 68a2e4d48b [SimplifyDemandedVec] Strengthen handling all undef lanes (particularly GEPs)
A change of two parts:
1) A generic enhancement for all callers of SDVE to exploit the fact that if all lanes are undef, the result is undef.
2) A GEP specific piece to strengthen/fix the vector index undef element handling, and call into the generic infrastructure when visiting the GEP.

The result is that we replace a vector gep with at least one undef in each lane with a undef.  We can also do the same for vector intrinsics.  Once the masked.load patch (D57372) has landed, I'll update to include call tests as well.

Differential Revision: https://reviews.llvm.org/D57468

llvm-svn: 356293
2019-03-15 19:54:06 +00:00
Robert Widmann 2f1ebe6ee8 [LLVM-C] Expose the "Add Discriminators" Pass To LLVM-C
Summary: Add bindings to create a wrapped "Add Discriminators" pass.  Now that we have debug info support, this is a handy transform to have.

Reviewers: whitequark, deadalnix

Reviewed By: whitequark

Subscribers: dblaikie, aprantl, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58624

llvm-svn: 356272
2019-03-15 16:57:23 +00:00
Teresa Johnson 70ec64cb72 [ThinLTO] Restructure AliasSummary to contain ValueInfo of Aliasee
Summary:
The AliasSummary previously contained the AliaseeGUID, which was only
populated when reading the summary from bitcode. This patch changes it
to instead hold the ValueInfo of the aliasee, and always populates it.
This enables more efficient access to the ValueInfo (specifically in the
recent patch r352438 which needed to perform an index hash table lookup
using the aliasee GUID).

As noted in the comments in AliasSummary, we no longer technically need
to keep a pointer to the corresponding aliasee summary, since it could
be obtained by walking the list of summaries on the ValueInfo looking
for the summary in the same module. However, I am concerned that this
would be inefficient when walking through the index during the thin
link for various analyses. That can be reevaluated in the future.

By always populating this new field, we can remove the guard and special
handling for a 0 aliasee GUID when dumping the dot graph of the summary.

An additional improvement in this patch is when reading the summaries
from LLVM assembly we now set the AliaseeSummary field to the aliasee
summary in that same module, which makes it consistent with the behavior
when reading the summary from bitcode.

Reviewers: pcc, mehdi_amini

Subscribers: inglorion, eraman, steven_wu, dexonsmith, arphaman, llvm-commits

Differential Revision: https://reviews.llvm.org/D57470

llvm-svn: 356268
2019-03-15 15:11:38 +00:00
Florian Hahn d9e88f7b7f [LSR] Check for signed overflow in NarrowSearchSpaceByDetectingSupersets.
We are adding a sign extended IR value to an int64_t, which can cause
signed overflows, as in the attached test case, where we have a formula
with BaseOffset = -1 and a constant with numeric_limits<int64_t>::min().

If the addition would overflow, skip the simplification for this
formula. Note that the target triple is required to trigger the failure.

Reviewers: qcolombet, gilr, kparzysz, efriedma

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D59211

llvm-svn: 356256
2019-03-15 12:17:36 +00:00
Matt Arsenault 1d83670dbd AMDGPU: Remove intrinsic operand assert
Before r355981, this was under LLVM_DEBUG. I don't think the assert is
quite right, but this really should be a verifier check. Instcombine
should not be asserting on this sort of thing.

llvm-svn: 356219
2019-03-14 23:45:09 +00:00
Sanjay Patel de1d5d3675 [InstCombine] canonicalize funnel shift constant shift amount to be modulo bitwidth
The shift argument is defined to be modulo the bitwidth, so if that argument
is a constant, we can always reduce the constant to its minimal form to allow
better CSE and other follow-on transforms.

We need to be careful to ignore constant expressions here, or we will likely
infinite loop. I'm adding a general vector constant query for that case.

Differential Revision: https://reviews.llvm.org/D59374

llvm-svn: 356192
2019-03-14 19:22:08 +00:00