Summary:
In D47428, i propose to choose the `~(-(1 << nbits))` as the canonical form of low-bit-mask formation.
As it is seen from these tests, there is a reason for that.
AArch64 currently better handles `~(-(1 << nbits))`, but not the more traditional `(1 << nbits) - 1` (sic!).
The other way around for X86.
It would be much better to canonicalize.
This patch is completely monkey-typing.
I don't really understand how this works :)
I have based it on `// x & (-1 >> (32 - y))` pattern.
Also, when we only have `BMI`, i wonder if we could use `BEXTR` with `start=0` ?
Related links:
https://bugs.llvm.org/show_bug.cgi?id=36419https://bugs.llvm.org/show_bug.cgi?id=37603https://bugs.llvm.org/show_bug.cgi?id=37610https://rise4fun.com/Alive/idM
Reviewers: craig.topper, spatel, RKSimon, javed.absar
Reviewed By: craig.topper
Subscribers: kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D47453
llvm-svn: 334125
Summary:
In D47428, i propose to choose the `~(-(1 << nbits))` as the canonical form of low-bit-mask formation.
As it is seen from these tests, there is a reason for that.
AArch64 currently better handles `~(-(1 << nbits))`, but not the more traditional `(1 << nbits) - 1` (sic!).
The other way around for X86.
It would be much better to canonicalize.
It would seem that there is too much tests, but this is most of all the auto-generated possible variants
of C code that one would expect for BZHI to be formed, and then manually cleaned up a bit.
So this should be pretty representable, which somewhat good coverage...
Related links:
https://bugs.llvm.org/show_bug.cgi?id=36419https://bugs.llvm.org/show_bug.cgi?id=37603https://bugs.llvm.org/show_bug.cgi?id=37610https://rise4fun.com/Alive/idM
Reviewers: javed.absar, craig.topper, RKSimon, spatel
Reviewed By: RKSimon
Subscribers: kristof.beyls, llvm-commits, RKSimon, craig.topper, spatel
Differential Revision: https://reviews.llvm.org/D47452
llvm-svn: 334124
Summary:
This change uses fmf subflags to guard optimizations as well as unsafe. These changes originated from D46483.
It contains only context for fsqrt.
Reviewers: spatel, hfinkel, arsenm
Reviewed By: spatel
Subscribers: hfinkel, wdng, andrew.w.kaylor, wristow, efriedma, nemanjai
Differential Revision: https://reviews.llvm.org/D47749
llvm-svn: 334113
Only the bottom 16-bits of BEXTR's control op are required (0:8 INDEX, 15:8 LENGTH).
Differential Revision: https://reviews.llvm.org/D47690
llvm-svn: 334083
This is a fix for the problem arising in D47374 (PR37678):
https://bugs.llvm.org/show_bug.cgi?id=37678
We may not have throughput info because it's not specified in the model
or it's not available with variant scheduling, so assume that those
instructions can execute/complete at max-issue-width.
Differential Revision: https://reviews.llvm.org/D47723
llvm-svn: 334055
CodeGenPrepare pass move extension instructions close to load instructions in different BB, so they can be combined later. But the extension instructions can't move through logical and shift instructions in current implementation. This patch enables this enhancement, so we can eliminate more extension instructions.
Differential Revision: https://reviews.llvm.org/D45537
This is re-commit of r331783, which was reverted by r333305. The performance regression was caused by some unlucky alignment, not a code generation problem.
llvm-svn: 334049
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
Ideally we'd use resolveTargetShuffleInputs to handle faux shuffles as well but:
(a) that code path doesn't handle general/pre-legalized ops/types very well.
(b) I'm concerned about the compute time as they recurse to calls to computeKnownBits/ComputeNumSignBits which would need depth limiting somehow.
llvm-svn: 334007
This is the new version of D46181, allowing setjmp/longjmp
to work correctly with the Intel CET shadow stack by storing
SSP on setjmp and fixing it on longjmp. The patch has been
updated to use the cf-protection-return module flag instead
of HasSHSTK, and the bug that caused D46181 to be reverted
has been fixed with the test expanded to track that fix.
patch by mike.dvoretsky
Differential Revision: https://reviews.llvm.org/D47311
llvm-svn: 333990
Passing -mattr=-mmx needs to disable these instructions since the MMX register class won't have been set up. But we don't want -mattr=-mmx to disable SSE so we have to do it separately.
llvm-svn: 333984
Start by emitting remarks for very basic unsupported cases such as
irreducible CFGs and EHFunclets. The end goal is to be able to cover all
the cases where we give up with an explanation.
llvm-svn: 333972
Summary: This include variant for add, uaddo and addcarry. usubo and subcarry require the carry to be flipped to preserve semantic, but we chose to do the transform anyway in that case as to push the transform down the carry chain.
Reviewers: efriedma, spatel, RKSimon, zvi, bkramer
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D46505
llvm-svn: 333943
This patch is the last of a sequence of three patches related to LLVM-dev RFC
"MC support for variant scheduling classes".
http://lists.llvm.org/pipermail/llvm-dev/2018-May/123181.html
This fixes PR36672.
The main goal of this patch is to teach llvm-mca how to solve variant scheduling
classes. This patch does that, plus it adds new variant scheduling classes to
the BtVer2 scheduling model to identify so-called zero-idioms (i.e. so-called
dependency breaking instructions that are known to generate zero, and that are
optimized out in hardware at register renaming stage).
Without the BtVer2 change, this patch would not have had any meaningful tests.
This patch is effectively the union of two changes:
1) a change that teaches llvm-mca how to resolve variant scheduling classes.
2) a change to the BtVer2 scheduling model that allows us to special-case
packed XOR zero-idioms (this partially fixes PR36671).
Differential Revision: https://reviews.llvm.org/D47374
llvm-svn: 333909
Ensure we test on 32-bit and 64-bit targets, and strip -mcpu usage.
Part of ongoing work to ensure we test all intrinsic style tests on 32 and 64 bit targets where possible.
llvm-svn: 333843
Further refactoring will wait until D47452 has landed.
Part of ongoing work to ensure we test all intrinsic style tests on 32 and 64 bit targets where possible.
llvm-svn: 333841
I had to tweak the i32 tests so we check both reg-reg and reg-mem cases.
I also added i64 load tests.
Part of ongoing work to ensure we test all intrinsic style tests on 32 and 64 bit targets where possible.
llvm-svn: 333827
Previously we just returned undef, but really we should be returning the pass thru input. We also need to make sure we preserve the chain output that the original intrinsic node had to maintain connectivity in the DAG. So we should just return the incoming chain as the output chain.
llvm-svn: 333804
The avx512f intrinsic tests were in the avx512vl file. We were also missing some combinations of masking.
This does show that we fail to use the zero masking form of expand loads when the passthru is zero. I'll try to get that fixed shortly.
llvm-svn: 333795
This patch replaces the --x86_extra_scrub command line argument to automatically support a second level of regex-scrubbing if it improves the matching of nearly-identical code patterns. The argument '--extra_scrub' is there now to force extra matching if required.
This is mostly useful to help us share 32-bit/64-bit x86 vector tests which only differs by retl/retq instructions, but any scrubber can now technically support this, meaning test checks don't have to be needlessly obfuscated.
I've updated some of the existing checks that had been manually run with --x86_extra_scrub, to demonstrate the extra "ret{{[l|q]}}" scrub now only happens when useful, and re-run the sse42-intrinsics file to show extra matches - most sse/avx intrinsics files should be able to now share 32/64 checks.
Tested with the opt/analysis scripts as well which share common code - AFAICT the other update scripts use their own versions.
Differential Revision: https://reviews.llvm.org/D47485
llvm-svn: 333749
Noticed while fixing PR37426, for splat rotations (rotation by an uniform value) its better to just expand back to shift ops than performing as a general non-uniform rotation.
llvm-svn: 333661
Summary:
{FLDL2E, FLDL2T, FLDLG2, FLDLN2, FLDPI} were using WriteMicrocoded.
- I've measured the values for Broadwell, Haswell, SandyBridge, Skylake.
- For ZnVer1 and Atom, values were transferred form InstRWs.
- For SLM and BtVer2, I've guessed some values :(
Reviewers: RKSimon, craig.topper, andreadb
Subscribers: gbedwell, llvm-commits
Differential Revision: https://reviews.llvm.org/D47585
llvm-svn: 333656
Summary:
- I've measured the values for Broadwell, Haswell, SandyBridge, Skylake.
- For ZnVer1 and Atom, values were transferred form `InstRW`s.
- For SLM and BtVer2, values are from Agner.
This is split off from https://reviews.llvm.org/D47377
Reviewers: RKSimon, andreadb
Subscribers: gbedwell, llvm-commits
Differential Revision: https://reviews.llvm.org/D47523
llvm-svn: 333642
This improves splat rotations (rotation by an uniform value), to avoid having to use the generic non-uniform shift code (extension to PR37426).
llvm-svn: 333641
Support for Clang lowering of fused intrinsics. This patch:
1. Removes bindings to clang fma intrinsics.
2. Introduces new LLVM unmasked intrinsics with rounding mode:
int_x86_avx512_vfmadd_pd_512
int_x86_avx512_vfmadd_ps_512
int_x86_avx512_vfmaddsub_pd_512
int_x86_avx512_vfmaddsub_ps_512
supported with a new intrinsic type (INTR_TYPE_3OP_RM).
3. Introduces new x86 fmaddsub/fmsubadd folding.
4. Introduces new tests for code emitted by sequentions introduced in Clang part.
Patch by tkrupa
Reviewers: craig.topper, sroland, spatel, RKSimon
Reviewed By: craig.topper, RKSimon
Differential Revision: https://reviews.llvm.org/D47443
llvm-svn: 333554
It was noticed on D47377 that these tests were being unnecessarily affected by scheduler changes.
This adds vzeroupper at the end of some tests as we lose the 'FeatureFastPartialYMMorZMMWrite' feature from KNL, since Skylake+ don't support this its probably better.
llvm-svn: 333549
1. Introduction of mask scalar TableGen patterns.
2. Introduction of new scalar move TableGen patterns
and refactoring of existing ones.
3. Folding of pattern created by introducing scalar
masking in Clang header files.
Patch by tkrupa
Differential Revision: https://reviews.llvm.org/D47012
llvm-svn: 333419
Summary:
Avoid assert/crash during liveness calculation in situations
where the incoming machine function has statically unreachable BBs.
Second attempt at submitting; this version of the change includes
a revised testcase.
Fixes PR37130.
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D47372
llvm-svn: 333416
Summary: We already get this right if the i64 didn't come from a load.
Reviewers: RKSimon
Reviewed By: RKSimon
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D47439
llvm-svn: 333393
We have unmasked intrinsics now and wrap them with a select. This is a net reduction of 36 intrinsics from before the unmasked intrinsics were added.
llvm-svn: 333388
This will allow us to remove the 3 different flavors of masked intrinsics. I'm leaving the actual intrinsic removal for another patch.
llvm-svn: 333386
These do the same thing with the first and second sources swapped. They previously came from separate intrinsics that specified different masking behavior. But we can cover that with isel patterns and a single node.
This is a step towards reducing the number of intrinsics needed.
A bunch of tests change because we are now biased to choosing VPERMT over VPERMI when there is nothing to signal that commuting is beneficial.
llvm-svn: 333383
As confirmed by llvm-exegesis, there is no scheduler difference between MOVDQA/MOVDQU and VMOVDQA/VMOVDQU xmm reg-reg moves
Another chapter in the never ending crusade to remove useless InstRW overrides from the x86 scheduler models......
llvm-svn: 333271
Re-add the feature flag for invpcid, which was removed in r294561.
Add an intrinsic, which always uses a 32 bit integer as first argument,
while the instruction actually uses a 64 bit register in 64 bit mode
for the INVPCID_TYPE argument.
Reviewers: craig.topper
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D47141
llvm-svn: 333255
In DWARF v5, the DWO ID is in the (split/skeleton) CU header, not an
attribute on the CU DIE.
This changes the size of those headers, so use the parsed size whenever
we have one, for simplicitly.
Differential Revision: https://reviews.llvm.org/D47158
llvm-svn: 333004
This is the FP sibling of D43141 with the corresponding IR change in rL327212.
We can't propagate undef here because if a variable operand is a NaN, these
binops must propagate NaN. Neither global nor node-level fast-math makes a
difference. If we have 'nnan', I think later folds can turn the NaN into undef.
The tests in X86/fp-undef.ll are meant to be the definitive verification for
these folds - everything reduces identically now.
The other test changes are collateral damage. They may need to be altered to
preserve their intent.
Differential Revision: https://reviews.llvm.org/D47026
llvm-svn: 332920
Summary:
As pointed out in D46528, we errneously transform cases like `xor X, -1`,
even though we use said function.
It's because the `-1` is actually a bitcast there.
So i think we can just look through it in the function.
Differential Revision: https://reviews.llvm.org/D47156
llvm-svn: 332905
Summary:
This **appears** to be the last missing piece for the masked merge pattern handling in the backend.
This is [[ https://bugs.llvm.org/show_bug.cgi?id=37104 | PR37104 ]].
[[ https://bugs.llvm.org/show_bug.cgi?id=6773 | PR6773 ]] will introduce an IR canonicalization that is likely bad for the end assembly.
Previously, `andps`+`andnps` / `bsl` would be generated. (see `@out`)
Now, they would no longer be generated (see `@in`), and we need to make sure that they are generated.
Differential Revision: https://reviews.llvm.org/D46528
llvm-svn: 332904
SimplifyDemandedBits can remove bits from the masks for the shift amounts we need to see to detect rotates.
This patch uses zeroes from computeKnownBits to fill in some of these mask bits to make the match work.
As currently written this calls computeKnownBits even when the mask hasn't been simplified because it made the code simpler. If we're worried about compile time performance we can improve this.
I know we're talking about making a rotate intrinsic, but hopefully we can go ahead and do this change and just make sure the rotate intrinsic also handles it.
Differential Revision: https://reviews.llvm.org/D47116
llvm-svn: 332895
This removes 6 intrinsics since we no longer need separate mask and maskz intrinsics.
Differential Revision: https://reviews.llvm.org/D47124
llvm-svn: 332890
As suggested by Fabian on PR37426, we can use PMULUDQ to perform v4i32 vector rotations as the upper 32bits of the multiply will contain the 'wrapped' bits of the rotation.
v8i16/v16i8 rotations would be straightforward to add to lowerRotate in the future - ideally we'd mostly share code with the vector shifts lowering.
Differential Revision: https://reviews.llvm.org/D46954
llvm-svn: 332832
BtVer2 - fix NumMicroOp and account for the Lat+6cy GPR->XMM and Lat+1cy XMm->GPR delays (see rL332737)
The high number of MOVD/MOVQ equivalent instructions meant that there were a number of missed patterns in SNB/Znver1:
SNB - add missing GPR<->MMX costs (taken from Agner / Intel AOM)
Znver1 - add missing GPR<->XMM MOVQ costs (taken from Agner)
llvm-svn: 332745
The intrinsic legalization for masked truncate uses ISD::TRUNCATE which can be constant folded by getNode. This prevents getVectorMaskingNode from seeing the ISD::TRUNCATE special case where it should emit X86ISD::SELECT instead of ISD::VSELECT. This causes a vselect with a v16i1 or v8i1 condition to be emitted during vector legalization. but vector legalization doesn't revisit nodes it creates. DAG combine will then promote this condition to match the result type. Then op legalization will try to legalize it, but the custom lowering hook returned SDValue(). But op legalization doesn't have an Expand for VSELECT because it expects vector legalization to have taken care of it. So the operation sticks around and fails in isel.
This patch adds a custom legalization hook to morph it to a vXi8 vselect instead.
This also simplifies the normal vXi16 vselect handling because vector legalization was normally expanding to AND/ANDN/OR and DAG combine was turning that into VBLENDVB. So we can skip a step by doing it directly.
Fixes PR37499
Differential Revision: https://reviews.llvm.org/D47025
llvm-svn: 332743
This is a revert of the changes from https://reviews.llvm.org/D46265;
the new test introduced (test/CodeGen/X86/PR37310.mir) causes buildbot
failures.
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D47061
llvm-svn: 332742
Summary:
Avoid assert/crash during liveness calculation in situations where the
incoming machine function has statically unreachable BBs.
Fixes PR37130.
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D46265
llvm-svn: 332707
Roman Lebedev