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Commit Graph

183627 Commits

Author SHA1 Message Date
Fangrui Song
b648113afa [llvm-readobj] Prepend argv[0] to error/warning messages
Summary:
Currently, we report:

    error: ...

Prepend argv[0] (tool name):

    llvm-readobj: error: ...

This is consistent with most GNU binutils/clang/lld, and gives a bit
more context in a long build log.

Reviewed By: grimar, jhenderson, rupprecht

Differential Revision: https://reviews.llvm.org/D66425

llvm-svn: 369377
2019-08-20 12:49:15 +00:00
Sanjay Patel
728efc9012 [InstCombine] add tests for min/max with min/max of same operands; NFC
llvm-svn: 369376
2019-08-20 12:49:03 +00:00
Alex Bradbury
5467ceb0ea [RISCV] Implement getExprForFDESymbol to ensure RISCV_32_PCREL is used for the FDE location
Follow binutils in using RISCV_32_PCREL for the FDE initial location. As
explained in the relevant binutils commit
<a6cbf936e3>,
the ADD/SUB pair of relocations is problematic in the presence of linker
relaxation.

This patch has the same end goal as D64715 but includes test changes and
avoids adding a new global VariantKind to MCExpr.h (preferring
RISCVMCExpr VKs like the rest of the RISC-V backend).

Differential Revision: https://reviews.llvm.org/D66419

llvm-svn: 369375
2019-08-20 12:32:31 +00:00
Pavel Labath
06e6938b76 Recommit "MemoryBuffer: Add a missing error-check to getOpenFileImpl"
This recommits r368977, which was reverted in r369027 due to test
failures in lldb. The cause of this was different behavior of
readNativeFileSlice on windows and unix. These have been addressed in
r369269.

The original commit message was:
In case the function was called with a desired read size *and* the file
was not an "mmap()" candidate, the function was falling back to a
"pread()", but it was failing to check the result of that system call.
This meant that the function would return "success" even though the read
operation failed, and it returned a buffer full of uninitialized memory.

Reviewers: rnk, dblaikie

Subscribers: kristina, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66224

llvm-svn: 369370
2019-08-20 12:08:52 +00:00
Simon Pilgrim
372c62cc4c [CMake] Update C4324 MSVC warning comment to explain its still broken at VS2019
As promised, I've updated the comment for the C4324 MSVC warning that was re-disabled at rL367409 / rG8f823e63e3edf87ab029ba32b68f3eb5d2f392b5 to put it in terms of currently supported VS versions

llvm-svn: 369368
2019-08-20 11:20:05 +00:00
Simon Pilgrim
aa50d0d398 [MCA][X86] Add tests for LOCK variants of standard X86 arithmetic ops
D66424 adds the base support for LOCK so we should be able to add special case support for all these cases in future patches

llvm-svn: 369367
2019-08-20 11:13:20 +00:00
Simon Pilgrim
e0da28268f Fix MSVC "result of 32-bit shift implicitly converted to 64 bits" warning. NFCI.
llvm-svn: 369366
2019-08-20 10:25:57 +00:00
Andrea Di Biagio
d5dd3f579a [X86][Btver2] Fix latency and throughput of CMPXCHG instructions.
On Jaguar, CMPXCHG has a latency of 11cy, and a maximum throughput of 0.33 IPC.
Throughput is superiorly limited to 0.33 because of the implicit in/out
dependency on register EAX. In the case of repeated non-atomic CMPXCHG with the
same memory location, store-to-load forwarding occurs and values for sequent
loads are quickly forwarded from the store buffer.

Interestingly, the functionality in LLVM that computes the reciprocal throughput
doesn't seem to know about RMW instructions. That functionality only looks at
the "consumed resource cycles" for the throughput computation. It should be
fixed/improved by a future patch. In particular, for RMW instructions, that
logic should also take into account for the write latency of in/out register
operands.

An atomic CMPXCHG has a latency of ~17cy. Throughput is also limited to
~17cy/inst due to cache locking, which prevents other memory uOPs to start
executing before the "lock releasing" store uOP.

CMPXCHG8rr and CMPXCHG8rm are treated specially because they decode to one less
macro opcode. Their latency tend to be the same as the other RR/RM variants. RR
variants are relatively fast 3cy (but still microcoded - 5 macro opcodes).

CMPXCHG8B is 11cy and unfortunately doesn't seem to benefit from store-to-load
forwarding. That means, throughput is clearly limited by the in/out dependency
on GPR registers. The uOP composition is sadly unknown (due to the lack of PMCs
for the Integer pipes). I have reused the same mix of consumed resource from the
other CMPXCHG instructions for CMPXCHG8B too.
LOCK CMPXCHG8B is instead 18cycles.

CMPXCHG16B is 32cycles. Up to 38cycles when the LOCK prefix is specified. Due to
the in/out dependencies, throughput is limited to 1 instruction every 32 (or 38)
cycles dependeing on whether the LOCK prefix is specified or not.
I wouldn't be surprised if the microcode for CMPXCHG16B is similar to 2x
microcode from CMPXCHG8B. So, I have speculatively set the JALU01 consumption to
2x the resource cycles used for CMPXCHG8B.

The two new hasLockPrefix() functions are used by the btver2 scheduling model
check if a MCInst/MachineInst has a LOCK prefix. Calls to hasLockPrefix() have
been encoded in predicates of variant scheduling classes that describe lat/thr
of CMPXCHG.

Differential Revision: https://reviews.llvm.org/D66424

llvm-svn: 369365
2019-08-20 10:23:55 +00:00
Seiya Nuta
d310c5451f [yaml2obj/obj2yaml][MachO] Fix a test failure in big endian hosts
These section contents are dummy data (0xdeadbeef) and it's endianess
does not matter.

- http://lab.llvm.org:8011/builders/clang-ppc64be-linux/builds/37265

llvm-svn: 369360
2019-08-20 09:58:31 +00:00
Igor Kudrin
2ee0278731 [DWARF] Fix DWARFUnit::getDebugInfoSize() for 64-bit DWARF.
The calculation there was correct only for DWARF32.

Differential Revision: https://reviews.llvm.org/D66421

llvm-svn: 369356
2019-08-20 09:50:44 +00:00
Seiya Nuta
52efdb7adc [yaml2obj/obj2yaml][MachO] Allow setting custom section data
Reviewers: alexshap, jhenderson, rupprecht

Reviewed By: alexshap, jhenderson

Subscribers: abrachet, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65799

llvm-svn: 369348
2019-08-20 08:49:07 +00:00
Seiya Nuta
d6e74f9c7c [llvm-objcopy][MachO] Fix method names. NFC.
Reviewers: alexshap, rupprecht, jhenderson

Reviewed By: alexshap, rupprecht

Subscribers: jakehehrlich, abrachet, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65540

llvm-svn: 369346
2019-08-20 08:36:47 +00:00
George Rimar
aac454ba82 [test/Object] - Move/rewrite 2 more test cases.
This patch makes a change for test/Object tests responsible
for relocations.

* 2 tests were moved to llvm-readobj/llvm-objdump folders:
Object/elf-reloc-no-sym.test -> tools/llvm-readobj/elf-reloc-no-sym.test
Object/objdump-reloc-shared.test -> tools/llvm-objdump/relocations-in-nonreloc.test

* A prerecompiled binary was removed and these tests were refactored.

Differential revision: https://reviews.llvm.org/D66291

llvm-svn: 369342
2019-08-20 08:23:57 +00:00
Fangrui Song
0141652683 [MC] Delete an overload of MCExpr::evaluateKnownAbsolute and its associated hack
The hack dated back to 2010 (r121076) and was documented by r122144:

  // FIXME: The use if InSet = Addrs is a hack. Setting InSet causes us
  // absolutize differences across sections and that is what the MachO writer
  // uses Addrs for.

llvm-svn: 369337
2019-08-20 07:42:04 +00:00
Fangrui Song
a458870688 [Attributor] Fix -Wunused-variable in -DLLVM_ENABLE_ASSERTIONS=off builds after r369331
llvm-svn: 369334
2019-08-20 07:21:43 +00:00
Craig Topper
4f9e2bf436 [X86] Add back the -x86-experimental-vector-widening-legalization comand line flag and all associated code, but leave it enabled by default
Google is reporting performance issues with the new default behavior
and have asked for a way to switch back to the old behavior while we
investigate and make fixes.

I've restored all of the code that had since been removed and added
additional checks of the command flag onto code paths that are
not otherwise guarded by a check of getTypeAction.

I've also modified the cost model tables to hopefully get us back
to the previous costs.

Hopefully we won't need to support this for very long since we
have no test coverage of the old behavior so we can very easily
break it.

llvm-svn: 369332
2019-08-20 06:58:00 +00:00
Johannes Doerfert
45e6a509d0 [Attributor] Create abstract attributes on-demand
Before, we create the set of abstract attributes initially and then
dealt with the fact hat a lookup could fail, e.g., return a nullptr.
This patch will ensure we always return a valid object from a lookup,
allowing us not only to remove the nullptr checks but also to grow the
set of abstract attributes "in-flight" on-demand.

One can now start from those that have the best chance of improving
performance without the need to specify all they might depend on.

While this introduces some boilerplate, the usage of attributes is much
easier and cleaner now.

Reviewers: uenoku, sstefan1

Subscribers: hiraditya, bollu, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66276

llvm-svn: 369331
2019-08-20 06:15:50 +00:00
Johannes Doerfert
76537d874a [Attributor][NFC] Cleanup statistics code
llvm-svn: 369330
2019-08-20 06:09:56 +00:00
Johannes Doerfert
8c11d0e37f [Attributor] Use structured deduction for AADereferenceable
Summary:
This is analogous to D66128 but for AADereferenceable. We have the logic
concentrated in the floating value updateImpl and we use the combiner
helper classes for arguments and return values.

The regressions will go away with "on-demand" attribute creation.
Improvements are already visible in the existing tests.

Reviewers: uenoku, sstefan1

Subscribers: hiraditya, bollu, jfb, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66272

llvm-svn: 369329
2019-08-20 06:08:35 +00:00
Johannes Doerfert
95f3dc61a8 [Attributor] Use structured deduction for AANonNull
Summary:
What D66126 did for AAAlign, this patch does for AANonNull. Agian, the
logic becomes more concise and localized. Again, returned poiners are
not annotated properly but that will not be an issue if this lands with
the "on-demand" generation of attributes. First improvements due to the
genericValueTraversal are already visible.

Reviewers: sstefan1, uenoku

Subscribers: hiraditya, bollu, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66128

llvm-svn: 369328
2019-08-20 06:02:39 +00:00
Johannes Doerfert
b23b231c6a [Attributor] Fix the "clamp" operator
The clamp operator should not take the known of the given state as the
known is potentially based on assumed information. This also adds TODOs
to guide improvements.

llvm-svn: 369327
2019-08-20 05:57:01 +00:00
Thomas Raoux
74ef61ec21 [NFC] Test commit, fix some comment spelling.
llvm-svn: 369326
2019-08-20 05:21:27 +00:00
Karl-Johan Karlsson
819807445d [AsmPrinter] Remove const qualifier from EmitBasicBlockStart.
Overriders may want to modify state in it. AMDGPU wants
to, but has to make its members mutable in order to do so.

Besides, EmitBasicBlockEnd is not const, so why should
Start be?

Patch by Bevin Hansson.

Reviewed By: nickdesaulniers

Differential Revision: https://reviews.llvm.org/D66341

llvm-svn: 369325
2019-08-20 05:13:57 +00:00
Fangrui Song
8d6d56021f MCAsmMacro: add #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) to some dump() declarations
llvm-svn: 369324
2019-08-20 04:14:43 +00:00
Fangrui Song
bd9f504359 [WebAssembly][MC] Fix -Wunused-variable in -DLLVM_ENABLE_ASSERTIONS=off builds after r369317
llvm-svn: 369318
2019-08-20 02:02:57 +00:00
Sam Clegg
ed51349261 [WebAssembly][MC] Simplify WasmObjectWriter::recordRelocation. NFC.
WebAssembly doesn't support PC relative relocation or relocation
expressions that can't be reduced to single symbol.

The only support for we have for fixups involving two symbols are when
both symbols are defined and withing the same section.  In this case
evaluateFixup will already have evaluated to the expression before
calling recordRelocation.

llvm-svn: 369317
2019-08-20 00:33:50 +00:00
Dinar Temirbulatov
3a0d7be9f3 [SLP][NFC] Avoid repetitive calls to getSameOpcode()
We can avoid repetitive calls getSameOpcode() for already known tree elements by keeping MainOp and AltOp in TreeEntry.

Differential Revision: https://reviews.llvm.org/D64700

llvm-svn: 369315
2019-08-20 00:22:04 +00:00
Hubert Tong
f12628ef2a [cmake] Link in LLVMPasses due to dependency by LLVMOrcJIT; NFC
Summary:
rL367756 (f5c40cb) increases the dependency of LLVMOrcJIT on LLVMPasses.
In particular, symbols defined in LLVMPasses that are referenced by the
destructor of `PassBuilder` are now referenced by LLVMOrcJIT through
`Speculation.cpp.o`.

We believe that referencing symbols defined in LLVMPasses in the
destructor of `PassBuilder` is valid, and that adding to the set of such
symbols is legitimate. To support such cases, this patch adds LLVMPasses
to the set of libraries being linked when linking in LLVMOrcJIT causes
such symbols from LLVMPasses to be referenced.

Reviewers: Whitney, anhtuyen, pree-jackie

Reviewed By: pree-jackie

Subscribers: mgorny, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66441

llvm-svn: 369310
2019-08-19 23:12:48 +00:00
Joel E. Denny
eaf7cad4eb [lit] Check for accidental external command calls
This patch extends lit's test suite to check that lit's internal shell
doesn't accidentally execute internal commands as external commands.
It does so by putting fake failing versions of those commands in
`PATH` while the entire lit test suite is running.  Without the fixes
in D65697 but with its tests, this approach catches accidental
external `env` calls.

Reviewed By: probinson

Differential Revision: https://reviews.llvm.org/D66293

llvm-svn: 369309
2019-08-19 22:59:37 +00:00
Anton Afanasyev
a8dfb73265 [Support][Time profiler] Make FE codegen blocks to be inside frontend blocks
Summary:
Add `Frontend` time trace entry to `HandleTranslationUnit()` function.
Add test to check all codegen blocks are inside frontend blocks.
Also, change `--time-trace-granularity` option a bit to make sure very small
time blocks are outputed to json-file when using `--time-trace-granularity=0`.

This fixes http://llvm.org/pr41969

Reviewers: russell.gallop, lebedev.ri, thakis

Reviewed By: russell.gallop

Subscribers: vsapsai, aras-p, lebedev.ri, hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D63325

llvm-svn: 369308
2019-08-19 22:58:26 +00:00
Matthias Gehre
e16b3dbe3a [ORC] fix use-after-free detected by -Wreturn-stack-address
Summary:
llvm/lib/ExecutionEngine/Orc/Layer.cpp:53:12: warning: returning address of local temporary object [-Wreturn-stack-address]

In
```
StringRef IRMaterializationUnit::getName() const {
[...]
     return TSM.withModuleDo(
        [](const Module &M) { return M.getModuleIdentifier(); });
```
`getModuleIdentifier()` returns a `const std::string &`, but the implicit return type
of the lambda is `std::string` by value, and thus the returned `StringRef` refers
to a temporary `std::string`.

Detect by annotating `llvm::StringRef` with `[[gsl::Pointer]]`.

Reviewers: lhames, sgraenitz

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66440

llvm-svn: 369306
2019-08-19 21:59:44 +00:00
Johannes Doerfert
3f511ba363 [CaptureTracker] Let subclasses provide dereferenceability information
Summary:
CaptureTracker subclasses might have better dereferenceability
information which allows null pointer checks to be no-capturing.
The first user will be D59922.

Reviewers: sanjoy, hfinkel, aykevl, sstefan1, uenoku, xbolva00

Subscribers: hiraditya, bollu, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66371

llvm-svn: 369305
2019-08-19 21:56:38 +00:00
Johannes Doerfert
b1462f01b6 Recommit "[Attributor] Fix: Do not partially resolve returned calls."
This reverts commit b1752f670f3d6393306dd5d37546b6e23384d8a2.

Fixed the issue with a different commit, reapply this one as it was,
afaik, not broken.

llvm-svn: 369303
2019-08-19 21:35:31 +00:00
Seiya Nuta
aba5322f2a Recommit "[llvm-objcopy][MachO] Implement a layout algorithm for executables"
Summary: The layout algorithm for relocatable objects and for executable are somewhat different. This patch implements the latter one based on the algorithm in LLD (MachOFileLayout).

Reviewers: alexshap, rupprecht, jhenderson

Reviewed By: alexshap

Subscribers: jakehehrlich, abrachet, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65539

llvm-svn: 369301
2019-08-19 21:12:02 +00:00
Evgeniy Stepanov
fddd9d319f Refactor isPointerOffset (NFC).
Summary:
Simplify the API using Optional<> and address comments in
         https://reviews.llvm.org/D66165

Reviewers: vitalybuka

Subscribers: hiraditya, llvm-commits, ostannard, pcc

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66317

llvm-svn: 369300
2019-08-19 21:08:04 +00:00
Vyacheslav Zakharin
2da6f9c522 Fixed placement of llvm.global_dtors on Windows.
Differential revision: https://reviews.llvm.org/D66373

llvm-svn: 369299
2019-08-19 21:07:03 +00:00
Seiya Nuta
c44c8db652 Recommit "[llvm-objcopy][MachO] Support load commands used in executables/shared libraries"
Summary:
This patch implements copying some load commands that appear in executables/shared libraries such as the indirect symbol table.

I don't add tests intentionally because this patch is incomplete: we need a layout algorithm for executables/shared libraries. I'll submit it as a separate patch with tests.

Reviewers: alexshap, rupprecht, jhenderson, compnerd

Reviewed By: alexshap

Subscribers: abrachet, mgorny, mgrang, MaskRay, mtrent, jakehehrlich, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D63395

llvm-svn: 369298
2019-08-19 21:05:31 +00:00
Evgeniy Stepanov
768d8b571a MemTag: stack initializer merging.
Summary:
MTE provides instructions to update memory tags and data at the same
time. This change makes use of those to generate more compact code for
stack variable tagging + initialization.

We collect memory store and memset instructions following an alloca or a
lifetime.start call, and replace them with the corresponding MTE
intrinsics. Since the intrinsics work on 16-byte aligned chunks, the
stored values are combined as necessary.

Reviewers: pcc, vitalybuka, ostannard

Subscribers: srhines, javed.absar, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66167

llvm-svn: 369297
2019-08-19 20:47:09 +00:00
Benjamin Kramer
39257e2226 [Support] Replace sys::Mutex with their standard equivalents.
Only use a recursive mutex if it can be locked recursively.

llvm-svn: 369295
2019-08-19 19:49:57 +00:00
Johannes Doerfert
f1df01d3ad Re-apply fixed "[Attributor] Fix: Make sure we set the changed flag"
This reverts commit cedd0d9a6e4b433e1cd6585d1d4d152eb5e60b11.

Re-apply the original commit but make sure the variables are initialized
(even if they are not used) so UBSan is not complaining.

llvm-svn: 369294
2019-08-19 19:14:10 +00:00
Sam Clegg
39e2f92942 [WebAssembly][MC] Allow empty assembly functions
Differential Revision: https://reviews.llvm.org/D66434

llvm-svn: 369292
2019-08-19 19:04:54 +00:00
Alina Sbirlea
5d82ced509 [MemorySSA] Rename uses when inserting memory uses.
Summary:
When inserting uses from outside the MemorySSA creation, we don't
normally need to rename uses, based on the assumption that there will be
no inserted Phis (if  Def existed that required a Phi, that Phi already
exists). However, when dealing with unreachable blocks, MemorySSA will
optimize away Phis whose incoming blocks are unreachable, and these Phis end
up being re-added when inserting a Use.
There are two potential solutions here:
1. Analyze the inserted Phis and clean them up if they are unneeded
(current method for cleaning up trivial phis does not cover this)
2. Leave the Phi in place and rename uses, the same way as whe inserting
defs.
This patch use approach 2.

Resolves first test in PR42940.

Reviewers: george.burgess.iv

Subscribers: Prazek, sanjoy.google, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66033

llvm-svn: 369291
2019-08-19 18:57:40 +00:00
Andrea Di Biagio
7f44363da1 [X86] Move scheduling tests for CMPXCHG to the corresponding resources-x86_64.s files. NFC
In D66424 it has been requested to move all the new tests added by r369278 into
resources-x86_64.s. That is because only the 8b/16 ops should be tested by
resources-cmpxchg.s. This partially reverts r369278.

llvm-svn: 369288
2019-08-19 18:20:30 +00:00
Craig Topper
531e6f449d [X86] Teach lowerV4I32Shuffle to only use broadcasts if the mask has more than one undef element. Prioritize shifts over broadcast in lowerV8I16Shuffle.
The motivating case are the changes in vector-reduce-add.ll where
we were doing extra work in the scalar domain instead of shuffling.
There may be some one use check that needs to be looked into there,
but this patch sidesteps the issue by avoiding broadcasts that
aren't really broadcasting.

Differential Revision: https://reviews.llvm.org/D66071

llvm-svn: 369287
2019-08-19 18:15:50 +00:00
Craig Topper
4054fdb457 [CGP] Remove ModifiedDT from the makeBitReverse loop
I don't think anything in this loop modifies the control flow and we don't restart any iteration after setting the flag.

This code was added in http://reviews.llvm.org/D16893 but looking at the test case added there the code that caused the dominator tree to change was merging blocks with their predecessor not the bitreverse optimization.

Differential Revision: https://reviews.llvm.org/D66366

llvm-svn: 369283
2019-08-19 18:02:24 +00:00
Andrea Di Biagio
f2f9d97508 [X86] Added extensive scheduling model tests for all the CMPXCHG variants. NFC
Addresses a review comment in D66424

llvm-svn: 369279
2019-08-19 17:07:26 +00:00
Stefan Stipanovic
ca1da865fa [Attributor] -attributor-verify has false positives. Temporarily remove
it, until resolved.

llvm-svn: 369277
2019-08-19 16:39:32 +00:00
Pavel Labath
5c31a20ba7 Filesystem/Windows: fix inconsistency in readNativeFileSlice API
Summary:
The windows version implementation of readNativeFileSlice, was trying to
match the POSIX behavior of not treating EOF as an error, but it was
only handling the case of reading from a pipe. Attempting to read past
the end of a regular file returns a slightly different error code, which
needs to be handled too. This patch adds ERROR_HANDLE_EOF to the list of
error codes to be treated as an end of file, and adds some unit tests
for the API.

This issue was found while attempting to land D66224, which caused a bunch of
lldb tests to start failing on windows.

Reviewers: rnk, aganea

Subscribers: kristina, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66344

llvm-svn: 369269
2019-08-19 15:40:49 +00:00
Roman Lebedev
120ce0f066 [TargetLowering] x s% C == 0 fold: vector divisor with INT_MIN handling
Summary:
The general fold is only valid for positive divisors.
Which effectively means, it is invalid for `INT_MIN` divisors,
and we currently bailout if we see them.

But that is too strict, we can just fix-up the results.
For that, let's do a second computation 'in parallel':
```
Name: srem -> and
Pre: isPowerOf2(C)
%o = srem i8 %X, C
%r = icmp eq %o, 0
  =>
%n = and i8 %X, C-1
%r = icmp eq %n, 0
```
https://rise4fun.com/Alive/Sup

And then just blend results: if the divisor was `INT_MIN`,
pick the value we got via bit-test,
else pick the value from general fold.

There's interesting observation - `ISD::ROTR` is set to
`LegalizeAction::Expand` before AVX512, so we should not
treat `INT_MIN` divisor as even; and as it can be seen
while `@test_srem_odd_even_one` improves on all run-lines,
`@test_srem_odd_even_INT_MIN` only improves for AVX512.

Reviewers: RKSimon, craig.topper, spatel

Reviewed By: RKSimon

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66300

llvm-svn: 369268
2019-08-19 15:01:42 +00:00
Serge Guelton
d9db87717d [nfc] Silent gcc warning
llvm-svn: 369266
2019-08-19 14:40:33 +00:00