Commit Graph

18611 Commits

Author SHA1 Message Date
Craig Topper 316c58e8f1 [X86] Improve detection of unneeded shift amount masking to also handle the case that the LHS has known zeroes in it
If the LHS has known zeros, the RHS immediate will have had bits removed. So call computeKnownBits to get the known zeroes so we can handle this case.

Differential Revision: https://reviews.llvm.org/D58475

llvm-svn: 354811
2019-02-25 19:42:47 +00:00
Simon Pilgrim c61f1e8e6c [X86] Merge ISD::ADD/SUB nodes into X86ISD::ADD/SUB equivalents (PR40483)
Avoid ADD/SUB instruction duplication by reusing the X86ISD::ADD/SUB results.

Includes ADD commutation - I tried to include NEG+SUB SUB commutation as well but this causes regressions as we don't have good combine coverage to simplify X86ISD::SUB.

Differential Revision: https://reviews.llvm.org/D58597

llvm-svn: 354771
2019-02-25 11:19:37 +00:00
Simon Pilgrim cfaf663a35 [X86] Combine zext(packus(x),packus(y)) -> concat(x,y) (PR39637)
Its proving tricky to combine shuffles across multiple vector sizes, so for now I'm adding this more specific combine - the pattern is common enough to be worth it as a first step.

llvm-svn: 354757
2019-02-24 19:57:52 +00:00
Craig Topper 3fe4bd464c [X86] Fix tls variable lowering issue with large code model
Summary:
The problem here is the lowering for tls variable. Below is the DAG for the code.
SelectionDAG has 11 nodes:

t0: ch = EntryToken
      t8: i64,ch = load<(load 8 from `i8 addrspace(257)* null`, addrspace 257)> t0, Constant:i64<0>, undef:i64
        t10: i64 = X86ISD::WrapperRIP TargetGlobalTLSAddress:i64<i32* @x> 0 [TF=10]
      t11: i64,ch = load<(load 8 from got)> t0, t10, undef:i64
    t12: i64 = add t8, t11
  t4: i32,ch = load<(dereferenceable load 4 from @x)> t0, t12, undef:i64
t6: ch = CopyToReg t0, Register:i32 %0, t4
And when mcmodel is large, below instruction can NOT be folded.

  t10: i64 = X86ISD::WrapperRIP TargetGlobalTLSAddress:i64<i32* @x> 0 [TF=10]
t11: i64,ch = load<(load 8 from got)> t0, t10, undef:i64
So "t11: i64,ch = load<(load 8 from got)> t0, t10, undef:i64" is lowered to " Morphed node: t11: i64,ch = MOV64rm<Mem:(load 8 from got)> t10, TargetConstant:i8<1>, Register:i64 $noreg, TargetConstant:i32<0>, Register:i32 $noreg, t0"

When llvm start to lower "t10: i64 = X86ISD::WrapperRIP TargetGlobalTLSAddress:i64<i32* @x> 0 [TF=10]", it fails.

The patch is to fold the load and X86ISD::WrapperRIP.

Fixes PR26906

Patch by LuoYuanke

Reviewers: craig.topper, rnk, annita.zhang, wxiao3

Reviewed By: rnk

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58336

llvm-svn: 354756
2019-02-24 19:33:37 +00:00
Craig Topper 5532a98737 [X86][SSE] Use pblendw for v4i32/v2i64 during isel.
Summary:

Previously we used BLENDPS/BLENDPD but that puts the blend in the FP domain. Under optsize, the two address instruction pass can cause blendps/blendpd to commute to blendps/blendpd. But we probably shouldn't do that if the original type was a integer. So use pblendw instead.

Reviewers: spatel, RKSimon

Reviewed By: RKSimon

Subscribers: jdoerfert, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58574

llvm-svn: 354755
2019-02-24 19:23:41 +00:00
Craig Topper ce2bd19c49 [X86] Correct some ADC/SBB with immediate scheduler data for Broadwell and Skylake.
Summary:
The AX/EAX/RAX with immediate forms are 2 uops just like the AL with immediate.

The modrm form with r8 and immediate is a single uop just like r16/r32/r64 with immediate.

Reviewers: RKSimon, andreadb

Reviewed By: RKSimon

Subscribers: gbedwell, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58581

llvm-svn: 354754
2019-02-24 19:23:39 +00:00
Craig Topper be3348573e [LegalizeTypes][AArch64][X86] Make type legalization of vector (S/U)ADD/SUB/MULO follow getSetCCResultType for the overflow bits. Make UnrollVectorOverflowOp properly convert from scalar boolean contents to vector boolean contents
Summary:
When promoting the over flow vector for these ops we should use the target's desired setcc result type. This way a v8i32 result type will use a v8i32 overflow vector instead of a v8i16 overflow vector. A v8i16 overflow vector will cause LegalizeDAG/LegalizeVectorOps to have to use v8i32 and truncate to v8i16 in its expansion. By doing this in type legalization instead, we get the truncate into the DAG earlier and give DAG combine more of a chance to optimize it.

We also have to fix unrolling to use the scalar setcc result type for the scalarized operation, and convert it to the required vector element type after the scalar operation. We have to observe the vector boolean contents when doing this conversion. The previous code was just taking the scalar result and putting it in the vector. But for X86 and AArch64 that would have only put a the boolean value in bit 0 of the element and left all other bits in the element 0. We need to ensure all bits in the element are the same. I'm using a select with constants here because that's what setcc unrolling in LegalizeVectorOps used.

Reviewers: spatel, RKSimon, nikic

Reviewed By: nikic

Subscribers: javed.absar, kristof.beyls, dmgreen, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58567

llvm-svn: 354753
2019-02-24 19:23:36 +00:00
Simon Pilgrim 4f4f9abdfa [X86][AVX] Rename lowerShuffleByMerging128BitLanes to lowerShuffleAsLanePermuteAndRepeatedMask. NFC.
Name better matches the other similar 'lane permute' and 'repeated mask' functions we have.

llvm-svn: 354749
2019-02-24 17:30:06 +00:00
Craig Topper be9eeb5526 Recommit r354363 "[X86][SSE] Generalize X86ISD::BLENDI support to more value types"
And its follow ups r354511, r354640.

A follow patch will fix the issue that caused it to be reverted.

llvm-svn: 354737
2019-02-23 21:41:42 +00:00
Craig Topper ccc860cb81 Recommit r354647 and r354648 "[LegalizeTypes] When promoting the result of EXTRACT_SUBVECTOR, also check if the input needs to be promoted. Use that to determine the element type to extract"
r354648 was a follow up to fix a regression "[X86] Add a DAG combine for (aext_vector_inreg (aext_vector_inreg X)) -> (aext_vector_inreg X) to fix a regression from my previous commit."

These were reverted in r354713 as their context depended on other patches that were reverted for a bug.

llvm-svn: 354734
2019-02-23 19:51:32 +00:00
Simon Pilgrim f383a47b7d [X86][AVX] combineInsertSubvector - remove concat_vectors(load(x),load(x)) --> sub_vbroadcast(x)
D58053/rL354340 added this to EltsFromConsecutiveLoads directly

llvm-svn: 354732
2019-02-23 18:53:03 +00:00
Simon Pilgrim 398d0b9e96 Fix MSVC constant truncation warnings. NFCI.
llvm-svn: 354731
2019-02-23 18:49:02 +00:00
Simon Pilgrim e08f177ea2 [X86][AVX] concat_vectors(scalar_to_vector(x),scalar_to_vector(x)) --> broadcast(x)
For AVX1, limit this to i32/f32/i64/f64 loading cases only.

llvm-svn: 354730
2019-02-23 18:34:05 +00:00
Simon Pilgrim 31793733a0 [X86][AVX] Shuffle->Permute+Blend if we have one v4f64/v4i64 shuffle input in place
Even on AVX1 we can pretty cheaply (VPERM2F128+VSHUFPD) permute a single v4f64/v4i64 input (on AVX2 its just a single VPERMPD), followed by a BLENDPD.

llvm-svn: 354729
2019-02-23 17:10:47 +00:00
Craig Topper 75afc0105c [X86] Sign extend the 8-bit immediate when commuting blend instructions to match isel.
Conversion from ConstantSDNode to MachineInstr sign extends immediates from their APInt representation to int64_t.

This commit makes sure we do the same for commuting. The tests changes show how this improves CSE. This issue was made worse by the MachineCSE using commuteInstruction to undo a commute. So we virtually guarantee the sign extend from isel would be lost.

The improved CSE also occurred with r354363, but that was reverted. I'm working to undo the revert, but wanted to get this fix in while it was easy to see the results.

llvm-svn: 354724
2019-02-23 08:34:10 +00:00
Reid Kleckner e3876637cf Revert r354363 & co "[X86][SSE] Generalize X86ISD::BLENDI support to more value types"
r354363 caused https://crbug.com/934963#c1, which has a plain C reduced
test case.

I also had to revert some dependent changes:
- r354648
- r354647
- r354640
- r354511

llvm-svn: 354713
2019-02-23 01:19:42 +00:00
Craig Topper a9697f24cf [X86] Enable custom splitting of v8i64/v16i32 sext/zext for avx/avx2 when input type will be promoted by the type legalize to 128-bits.
If the the input type will be promoted to 128 bits its better to put a sign_extend_inreg/and in the 128 bit register before the split occurs. Otherwise we end up doing it on each half in the wider register.

Some of the overflow arithmetic tests are regressions, but I think we can make some improvement using getSetccResultType in DAG combine and/or type legalization.

llvm-svn: 354709
2019-02-23 00:35:02 +00:00
Sanjay Patel a9e289174a [x86] allow narrowing of vector UINT_TO_FP
As discussed in:
D56864
D58197

Always use the narrow (128-bit) instruction when possible.
We already had the signed int version of this transform.

llvm-svn: 354675
2019-02-22 15:47:45 +00:00
Sanjay Patel 1baf7896cc [x86] simplify code in combineExtractSubvector; NFC
Only the 1st fold is attempted pre-legalization, but it requires
legal (simple) types too, so we don't need an EVT in any of the code.

llvm-svn: 354674
2019-02-22 15:28:22 +00:00
Craig Topper 3a391fc0e8 [X86] Add a DAG combine for (aext_vector_inreg (aext_vector_inreg X)) -> (aext_vector_inreg X) to fix a regression from my previous commit.
Type legalization is causing two nodes to be created here, but we can use a single node to extend from v8i16 to v2i64.

llvm-svn: 354648
2019-02-22 01:49:53 +00:00
Craig Topper 427404c769 [X86] Fix some copy/paste mistakes that caused a VR128 to be used as the address of a load in an isel pattern
This was introduced in r354511.

Fixes PR40811.

llvm-svn: 354640
2019-02-22 00:04:35 +00:00
Craig Topper 2b34fdc67f [X86] Remove hasSideEffects=1 from the X87 pseudos with folded load.
This was done in r321424 to prevent scheduling from reordering things. But now that we model FPCW as a dependency, I don't think the same scheduling we were trying to prevent can occur.

llvm-svn: 354628
2019-02-21 22:00:15 +00:00
Sanjay Patel 234a5e8ea4 [x86] vectorize more cast ops in lowering to avoid register file transfers
This is a follow-up to D56864.

If we're extracting from a non-zero index before casting to FP,
then shuffle the vector and optionally narrow the vector before doing the cast:

cast (extelt V, C) --> extelt (cast (extract_subv (shuffle V, [C...]))), 0

This might be enough to close PR39974:
https://bugs.llvm.org/show_bug.cgi?id=39974

Differential Revision: https://reviews.llvm.org/D58197

llvm-svn: 354619
2019-02-21 20:40:39 +00:00
Nirav Dave dce91c1edb [X86] Fix copy-paste error in @ccz flag.
@ccz operand should be equivalent to @cce.

llvm-svn: 354588
2019-02-21 15:28:31 +00:00
Simon Pilgrim e6b338cbef [X86][SSE] combineX86ShufflesRecursively - moved to generic op input index lookup. NFCI.
We currently bail if the target shuffle decodes to more than 2 input vectors, this change alters the input index to work for any number of inputs for when we drop that requirement.

llvm-svn: 354575
2019-02-21 12:24:49 +00:00
Nikita Popov c3b496de7a [SDAG] Support vector UMULO/SMULO
Second part of https://bugs.llvm.org/show_bug.cgi?id=40442.

This adds an extra UnrollVectorOverflowOp() method to SDAG, because
the general UnrollOverflowOp() method can't deal with multiple results.

Additionally we need to expand UMULO/SMULO during vector op
legalization, as it may result in unrolling, which may need additional
type legalization.

Differential Revision: https://reviews.llvm.org/D57997

llvm-svn: 354513
2019-02-20 20:41:44 +00:00
Craig Topper 31823fba2e [X86] Add more load folding patterns for blend instructions as a follow up to r354363.
This avoids depending on the peephole pass to do load folding.

Also adds some load folding for some insert_subvector patterns that use blend.

All of this was found by temporarily adding TB_NO_FORWARD to the blend immediate entries in the load folding tables.

I've added -disable-peephole to some of the affected tests from that experiment to ensure we're testing isel patterns.

llvm-svn: 354511
2019-02-20 20:18:20 +00:00
Simon Pilgrim dca47c659c [X86][SSE] combineX86ShufflesRecursively - begin generalizing the number of shuffle inputs. NFCI.
We currently bail if the target shuffle decodes to more than 2 input vectors, this is some initial cleanup that still has the limit but generalizes the opindices to an array that will be necessary when we drop the limit.

llvm-svn: 354489
2019-02-20 17:58:29 +00:00
Craig Topper e4025c5eb1 [X86] Remove FeatureSlowIncDec from Sandy Bridge and later Intel Core CPUs
Summary:
Inc and Dec were at one point slow on Intel CPUs due to their tendency to cause partial flag stalls on P6 derived CPU cores. This is because these instructions are defined to preserve the carry flag. This partial flag stall issue persisted until Sandy Bridge when flag merging was changed to be handled as a data dependency instead of as a stall until retirement. Sandy Bridge and later CPUs rename the C flag separately from OSPAZ so there is no flag merge needed on INC/DEC to preserve the C flag.

Given these improvements I don't know why INC/DEC was ever considered slow on Sandy Bridge. If anything they should have been disabled on the earlier CPUs instead.

Note after this patch, INC/DEC are still considered slow on Silvermont, Goldmont, Knights Landing and our generic "x86-64" CPU.

Reviewers: spatel, RKSimon, chandlerc

Reviewed By: chandlerc

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D58412

llvm-svn: 354436
2019-02-20 05:39:11 +00:00
Eric Christopher 2534592b9f Temporarily Revert "[X86][SLP] Enable SLP vectorization for 128-bit horizontal X86 instructions (add, sub)"
As this has broken the lto bootstrap build for 3 days and is
showing a significant regression on the Dither_benchmark results (from
the LLVM benchmark suite) -- specifically, on the
BENCHMARK_FLOYD_DITHER_128, BENCHMARK_FLOYD_DITHER_256, and
BENCHMARK_FLOYD_DITHER_512; the others are unchanged.  These have
regressed by about 28% on Skylake, 34% on Haswell, and over 40% on
Sandybridge.

This reverts commit r353923.

llvm-svn: 354434
2019-02-20 04:42:07 +00:00
Craig Topper 8eade09249 [X86] Mark FP32_TO_INT16_IN_MEM/FP32_TO_INT32_IN_MEM/FP32_TO_INT64_IN_MEM as clobbering EFLAGS to prevent mis-scheduling during conversion from SelectionDAG to MIR.
After r354178, these instruction expand to a sequence that uses an OR instruction. That OR clobbers EFLAGS so we need to state that to avoid accidentally using the clobbered flags.

Our tests show the bug, but I didn't notice because the SETcc instructions didn't move after r354178 since it used to be safe to do the fp->int conversion first.

We should probably convert this whole sequence to SelectionDAG instead of a custom inserter to avoid mistakes like this.

Fixes PR40779

llvm-svn: 354395
2019-02-19 22:37:00 +00:00
Craig Topper 6d0190f21c [X86] Don't consider functions ABI compatible for ArgumentPromotion pass if they view 512-bit vectors differently.
The use of the -mprefer-vector-width=256 command line option mixed with functions
using vector intrinsics can create situations where one function thinks 512 vectors
are legal, but another fucntion does not.

If a 512 bit vector is passed between them via a pointer, its possible ArgumentPromotion
might try to pass by value instead. This will result in type legalization for the two
functions handling the 512 bit vector differently leading to runtime failures.

Had the 512 bit vector been passed by value from clang codegen, both functions would
have been tagged with a min-legal-vector-width=512 function attribute. That would
make them be legalized the same way.

I observed this issue in 32-bit mode where a union containing a 512 bit vector was
being passed by a function that used intrinsics to one that did not. The caller
ended up passing in zmm0 and the callee tried to read it from ymm0 and ymm1.

The fix implemented here is just to consider it a mismatch if two functions
would handle 512 bit differently without looking at the types that are being
considered. This is the easist and safest fix, but it can be improved in the future.

Differential Revision: https://reviews.llvm.org/D58390

llvm-svn: 354376
2019-02-19 20:12:20 +00:00
Simon Pilgrim 0b3b9424ca [X86][SSE] Generalize X86ISD::BLENDI support to more value types
D42042 introduced the ability for the ExecutionDomainFixPass to more easily change between BLENDPD/BLENDPS/PBLENDW as the domains required.

With this ability, we can avoid most bitcasts/scaling in the DAG that was occurring with X86ISD::BLENDI lowering/combining, blend with the vXi32/vXi64 vectors directly and use isel patterns to lower to the float vector equivalent vectors.

This helps the shuffle combining and SimplifyDemandedVectorElts be more aggressive as we lose track of fewer UNDEF elements than when we go up/down through bitcasts.

I've introduced a basic blend(bitcast(x),bitcast(y)) -> bitcast(blend(x,y)) fold, there are more generalizations I can do there (e.g. widening/scaling and handling the tricky v16i16 repeated mask case).

The vector-reduce-smin/smax regressions will be fixed in a future improvement to SimplifyDemandedBits to peek through bitcasts and support X86ISD::BLENDV.

Reapplied after reversion at rL353699 - AVX2 isel fix was applied at rL354358, additional test at rL354360/rL354361

Differential Revision: https://reviews.llvm.org/D57888

llvm-svn: 354363
2019-02-19 18:05:42 +00:00
Simon Pilgrim dce9c2a811 [X86][AVX2] Hide VPBLENDD instructions behind AVX2 predicate
This was the cause of the regression in D57888 - the commuted load pattern wasn't hidden by the predicate so once we enabled v4i32 blends on SSE41+ targets then isel was incorrectly matched against AVX2+ instructions.

llvm-svn: 354358
2019-02-19 17:23:55 +00:00
Craig Topper 51a2e88990 [X86] Bugfix for nullptr check by klocwork
klocwork critical issues in CG files:

Patch by Xiang Zhang (xiangzhangllvm)

Differential Revision: https://reviews.llvm.org/D58363

llvm-svn: 354357
2019-02-19 17:16:23 +00:00
Craig Topper d8acfe69f0 X86AsmParser AVX-512: Return error instead of hitting assert
When parsing a sequence of tokens beginning with {, it will hit an assert and crash if the token afterwards is not an identifier. Instead of this, return a more verbose error as seen elsewhere in the function.

Patch by Brandon Jones (BrandonTJones)

Differential Revision: https://reviews.llvm.org/D57375

llvm-svn: 354356
2019-02-19 17:13:40 +00:00
Craig Topper 236e1ce1d9 [X86] Filter out tuning feature flags and a few ISA feature flags when checking for function inline compatibility.
Tuning flags don't have any effect on the available instructions so aren't a good reason to prevent inlining.

There are also some ISA flags that don't have any intrinsics our ABI requirements that we can exclude. I've put only the most basic ones like cmpxchg16b and lahfsahf. These are interesting because they aren't present in all 64-bit CPUs, but we have codegen workarounds when they aren't present.

Loosening these checks can help with scenarios where a caller has a more specific CPU than a callee. The default tuning flags on our generic 'x86-64' CPU can currently make it inline compatible with other CPUs. I've also added an example test for 'nocona' and 'prescott' where 'nocona' is just a 64-bit capable version of 'prescott' but in 32-bit mode they should be completely compatible.

I've based the implementation here of the similar code in AMDGPU.

Differential Revision: https://reviews.llvm.org/D58371

llvm-svn: 354355
2019-02-19 17:05:11 +00:00
Simon Pilgrim 9d575db85e [X86][AVX] Update VBROADCAST folds to always use v2i64 X86vzload
The VBROADCAST combines and SimplifyDemandedVectorElts improvements mean that we now more consistently use shorter (128-bit) X86vzload input operands.

Follow up to D58053

llvm-svn: 354346
2019-02-19 16:33:17 +00:00
Simon Pilgrim d6add74915 Cast from SDValue directly instead of superfluous getNode(). NFCI.
llvm-svn: 354343
2019-02-19 16:20:09 +00:00
Simon Pilgrim 952abcefe4 [X86][AVX] EltsFromConsecutiveLoads - Add BROADCAST lowering support
This patch adds scalar/subvector BROADCAST handling to EltsFromConsecutiveLoads.

It mainly shows codegen changes to 32-bit code which failed to handle i64 loads, although 64-bit code is also using this new path to more efficiently combine to a broadcast load.

Differential Revision: https://reviews.llvm.org/D58053

llvm-svn: 354340
2019-02-19 15:57:09 +00:00
Craig Topper c81e0c67ba [X86] Remove command line strings from the ProcIntel* features.
These should always follow the CPU string. There's no reason to control them independently.

llvm-svn: 354304
2019-02-19 03:04:14 +00:00
Sanjay Patel d8b4efcb6b [CGP] form usub with overflow from sub+icmp
The motivating x86 cases for forming the intrinsic are shown in PR31754 and PR40487:
https://bugs.llvm.org/show_bug.cgi?id=31754
https://bugs.llvm.org/show_bug.cgi?id=40487
..and those are shown in the IR test file and x86 codegen file.

Matching the usubo pattern is harder than uaddo because we have 2 independent values rather than a def-use.

This adds a TLI hook that should preserve the existing behavior for uaddo formation, but disables usubo
formation by default. Only x86 overrides that setting for now although other targets will likely benefit
by forming usbuo too.

Differential Revision: https://reviews.llvm.org/D57789

llvm-svn: 354298
2019-02-18 23:33:05 +00:00
Sanjay Patel fff628274d [x86] split more v8f32/v8i32 shuffles in lowering
Similar to D57867 - this is a small patch with lots of test diffs.
With half-vector-width narrowing potential, using an extract + 128-bit vshufps
is a win because it replaces a 256-bit shuffle with a 128-bit shufle.

This seems like it should be a win even for targets with 'fast-variable-shuffle',
but we are intentionally deferring that to an independent change to make sure
that is true.

Differential Revision: https://reviews.llvm.org/D58181

llvm-svn: 354279
2019-02-18 16:46:12 +00:00
Craig Topper ce3c5ac6a6 [X86] In FP_TO_INTHelper, when moving data from SSE register to X87 register file via the stack, use the same stack slot we use for the integer conversion.
No need for a separate stack slot. The lifetimes don't overlap.

Also fix the MachinePointerInfo for the final load after the integer conversion to indicate it came from the stack slot.

llvm-svn: 354234
2019-02-17 19:23:49 +00:00
Craig Topper db5aa955cb [X86] When type legalizing the result of a i64 fp_to_uint on 32-bit targets. Generate all of the ops as i64 and let them be legalized.
No need to manually split everything. We can let the type legalizer work for us.

The test change seems to be caused by some DAG ordering issue that was previously circumventing a one use check in LowerSELECT where FP selects are turned into blends if the setcc has one use. But it was running after an integer select and the same setcc had been legalized to cmov and X86SISD::CMP. This dropped the use count of the setcc, but wasn't what was intended.

llvm-svn: 354197
2019-02-16 08:25:42 +00:00
Craig Topper 61da80584d [X86] Don't prevent load folding for cvtsi2ss/cvtsi2sd based on hasPartialRegUpdate.
Preventing the load fold won't fix the partial register update since the
input we can fold is a GPR. So it will do nothing to prevent a false dependency
on an XMM register.

llvm-svn: 354193
2019-02-16 03:34:54 +00:00
Craig Topper db2f084aa9 [X86] Don't set exception mask bits when modifying FPCW to change rounding mode for fp->int conversion
When we need to do an fp->int conversion using x87 instructions, we need to temporarily change the rounding mode to 0b11 and perform a store. To do this we save the old value of the fpcw to the stack, then set the fpcw to 0xc7f, do the store, then restore fpcw. But the 0xc7f value forces the exception mask bits 1. While this is what they would be in the default FP environment, as we move to support changing the FP environments, we shouldn't make this assumption.

This patch changes the code to explicitly OR 0xc00 with the old value so that only the rounding mode is changed. Unfortunately, this requires two stack temporaries instead of one. One to hold the old value and one to hold the new value. Without two stack temporaries we would need an additional GPR. We already need one to do the OR operation in. This is similar to what gcc and icc do for this operation. Though they are both better at reusing the stack temporaries when there are multiple truncates in a function(or at least in a basic block)

Differential Revision: https://reviews.llvm.org/D57788

llvm-svn: 354178
2019-02-15 21:59:33 +00:00
Nirav Dave 7875841121 [X86] Fix LowerAsmOutputForConstraint.
Summary:
Update Flag when generating cc output.

Fixes PR40737.

Reviewers: rnk, nickdesaulniers, craig.topper, spatel

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58283

llvm-svn: 354163
2019-02-15 20:01:55 +00:00
Craig Topper 9c6a9276da [X86] Move all the SSE legality checks out of FP_TO_INTHelper and up to LowerFP_TO_INT. NFCI
These checks aren't needed on the call to FP_TO_INTHelper from the type legalizer for splitting i64. We always want to use X87 FIST/FISTT to memory there.

Moving up the SSE checks will allow this routine to focus on what it cares about and makes its return semantics cleaner.

llvm-svn: 354161
2019-02-15 19:21:39 +00:00
Simon Pilgrim 6ce08672fb [X86][AVX] lowerShuffleAsLanePermuteAndPermute - fully populate the lane shuffle mask (PR40730)
As detailed on PR40730, we are not correctly filling in the lane shuffle mask (D53148/rL344446) - we fill in for the correct src lane but don't add it to the correct mask element, so any reference to the correct element is likely to see an UNDEF mask index.

This allows constant folding to propagate UNDEFs prior to the lane mask being (correctly) lowered to vperm2f128.

This patch fixes the issue by fully populating the lane shuffle mask - this is more than is necessary (if we only filled in the required mask elements we might be able to match other shuffle instructions - broadcasts etc.), but its the most cautious approach as this needs to be cherrypicked into the 8.0.0 release branch.

Differential Revision: https://reviews.llvm.org/D58237

llvm-svn: 354117
2019-02-15 11:39:21 +00:00
Matt Arsenault 2a5488b877 X86: Replace isSafeToClobberEFLAGS implementation
Also use modifiesRegister instead of looping over operands.

llvm-svn: 354098
2019-02-15 04:01:39 +00:00
Nirav Dave 5ffdc43dc9 [X86] cleanup inline asm register generation. NFCI.
llvm-svn: 354042
2019-02-14 18:06:21 +00:00
Craig Topper 1d158dd930 [X86] Make (f80 (sint_to_fp (i16))) use fistps/fisttps instead of fistpl/fisttpl when SSE is enabled.
When SSE is enabled sint_to_fp with i16 is blindly promoted to i32, but that changes the behavior of f80 conversion.

Move the promotion to i16 to LowerFP_TO_INT so we can limit it based on the floating point type.

llvm-svn: 354003
2019-02-14 01:41:43 +00:00
Anton Afanasyev ca9aff9353 [X86][SLP] Enable SLP vectorization for 128-bit horizontal X86 instructions (add, sub)
Try to use 64-bit SLP vectorization. In addition to horizontal instrs
this change triggers optimizations for partial vector operations (for instance,
using low halfs of 128-bit registers xmm0 and xmm1 to multiply <2 x float> by
<2 x float>).

Fixes llvm.org/PR32433

llvm-svn: 353923
2019-02-13 08:26:43 +00:00
Craig Topper 9b61f48e4b [X86] Use default expansion for (i64 fp_to_uint f80) when avx512 is enabled on 64-bit targets to match what happens without avx512.
In 64-bit mode prior to avx512 we use Expand, but with avx512 we need to make f32/f64 conversions Legal so we use Custom and then do our own expansion for f80. But this seems to produce codegen differences relative to avx2. This patch corrects this.

llvm-svn: 353921
2019-02-13 07:42:34 +00:00
Craig Topper 3099e442a6 [X86] Refactor the FP_TO_INTHelper interface. NFCI
-Pull the final stack load creation from the two callers into the helper.
-Return a single SDValue instead of a std::pair.
-Remove the Replace flag which isn't really needed.

llvm-svn: 353920
2019-02-13 07:42:31 +00:00
Simon Pilgrim 5338f41ced [X86][AVX] Enable shuffle combining support for zero_extend
A more limited version of rL352997 that had to be disabled in rL353198 - allow extension of any 128/256/512 bit vector that at least uses byte sized scalars.

llvm-svn: 353860
2019-02-12 17:22:35 +00:00
Craig Topper 7670ede434 [X86] Collapse FP_TO_INT16_IN_MEM/FP_TO_INT32_IN_MEM/FP_TO_INT64_IN_MEM into a single opcode using memory VT to distinquish. NFC
llvm-svn: 353798
2019-02-12 06:14:18 +00:00
Craig Topper d7303ecd0b [X86] Remove the value type operand from the floating point load/store MemIntrinsicSDNodes. Use the MemoryVT instead. NFCI
We already have the memory VT, we can just match from that during isel.

llvm-svn: 353797
2019-02-12 06:14:16 +00:00
Craig Topper 75eb0af874 [X86] Correct the memory operand for the FLD emitted in FP_TO_INTHelper for 32-bit SSE targets.
We were using DstTy, but that represents the integer type we are converting to which is i64 in this
case. The FLD is part of an intermediate step to get from the SSE registers to the x87 registers.
If the floating point type is f32, the memory operand should reflect a 4 byte access not an 8 byte
access. The store we used to get from SSE to the stack is using the corect size.

While there, consistenly use TheVT in place of Op.getOperand(0).getValueType() throughout the function.

llvm-svn: 353745
2019-02-11 20:38:10 +00:00
Sam McCall e825ba9165 Revert "[X86][SSE] Generalize X86ISD::BLENDI support to more value types"
This reverts commit r353610.
It causes a miscompile visible in macro expansion in a bootstrapped clang.

http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20190211/626590.html

llvm-svn: 353699
2019-02-11 14:05:36 +00:00
Craig Topper 5b1beda001 [X86] Removed unused SDTypeProfile. NFC
llvm-svn: 353659
2019-02-11 07:30:48 +00:00
Simon Pilgrim f6e6c369c0 [X86] EltsFromConsecutiveLoads - replace SmallBitVector with APInt (NFC).
Minor refactor to simplify some incoming patches to improve broadcast loads.

llvm-svn: 353655
2019-02-10 22:45:48 +00:00
Sanjay Patel 833550fc74 [x86] narrow 256-bit horizontal ops via demanded elements
256-bit horizontal math ops are an x86 monstrosity (and thankfully have
not been extended to 512-bit AFAIK).

The two 128-bit halves operate on separate halves of the inputs. So if we
don't demand anything in the upper half of the result, we can extract the
low halves of the inputs, do the math, and then insert that result into a
256-bit output.

All of the extract/insert is free (ymm<-->xmm), so we're left with a
narrower (cheaper) version of the original op.

In the affected tests based on:
https://bugs.llvm.org/show_bug.cgi?id=33758
https://bugs.llvm.org/show_bug.cgi?id=38971
...we see that the h-op narrowing can result in further narrowing of other
math via existing generic transforms.

I originally drafted this patch as an exact pattern match starting from
extract_vector_elt, but I thought we might see diffs starting from
extract_subvector too, so I changed it to a more general demanded elements
solution. There are no extra existing regression test improvements from
that switch though, so we could go back.

Differential Revision: https://reviews.llvm.org/D57841

llvm-svn: 353641
2019-02-10 15:22:06 +00:00
Craig Topper f37ea96922 [X86] Move some vector InstAliases out from under unnecessary 'let Predicates'. NFCI
We don't have any assembler predicates for vector ISAs so this isn't necessary. It just adds extra lines and identation.

llvm-svn: 353631
2019-02-10 02:34:31 +00:00
Simon Pilgrim 6bf7b30b10 [X86] CombineOr - fold to generic funnel shifts
As discussed on D57389, this is a first step towards moving the SHLD/SHRD matching code to DAGCombiner using FSHL/FSHR instead.

There's a bit of work to do before I can do that, so this just folds to FSHL/FSHR in the existing code (handling the different SHRD/FSHR argument ordering), which fixes the issue we had with i16 shift amounts not being correctly masked.

llvm-svn: 353626
2019-02-09 20:34:59 +00:00
Simon Pilgrim 690a2889d8 [X86][SSE] Generalize X86ISD::BLENDI support to more value types
D42042 introduced the ability for the ExecutionDomainFixPass to more easily change between BLENDPD/BLENDPS/PBLENDW as the domains required.

With this ability, we can avoid most bitcasts/scaling in the DAG that was occurring with X86ISD::BLENDI lowering/combining, blend with the vXi32/vXi64 vectors directly and use isel patterns to lower to the float vector equivalent vectors.

This helps the shuffle combining and SimplifyDemandedVectorElts be more aggressive as we lose track of fewer UNDEF elements than when we go up/down through bitcasts.

I've introduced a basic blend(bitcast(x),bitcast(y)) -> bitcast(blend(x,y)) fold, there are more generalizations I can do there (e.g. widening/scaling and handling the tricky v16i16 repeated mask case).

The vector-reduce-smin/smax regressions will be fixed in a future improvement to SimplifyDemandedBits to peek through bitcasts and support X86ISD::BLENDV.

Differential Revision: https://reviews.llvm.org/D57888

llvm-svn: 353610
2019-02-09 13:13:59 +00:00
Craig Topper fcb63c4c6c [X86] Add FPCW as an implicit use on floating point load instructions.
These instructions can generate a stack overflow exception so technically they read the stack overflow exception mask bit.

llvm-svn: 353564
2019-02-08 20:50:09 +00:00
Craig Topper 784929d045 Implementation of asm-goto support in LLVM
This patch accompanies the RFC posted here:
http://lists.llvm.org/pipermail/llvm-dev/2018-October/127239.html

This patch adds a new CallBr IR instruction to support asm-goto
inline assembly like gcc as used by the linux kernel. This
instruction is both a call instruction and a terminator
instruction with multiple successors. Only inline assembly
usage is supported today.

This also adds a new INLINEASM_BR opcode to SelectionDAG and
MachineIR to represent an INLINEASM block that is also
considered a terminator instruction.

There will likely be more bug fixes and optimizations to follow
this, but we felt it had reached a point where we would like to
switch to an incremental development model.

Patch by Craig Topper, Alexander Ivchenko, Mikhail Dvoretckii

Differential Revision: https://reviews.llvm.org/D53765

llvm-svn: 353563
2019-02-08 20:48:56 +00:00
Craig Topper 41a1792b15 [X86] Remove isReMaterializable from X87 floating point constant loads and constant pool loads.
Summary: These instructions update FPSW so they aren't generically safe to rematerialize into any location if FPSW is live for a comparison result. They also use FPCW for exception masking control. Though the only exception they can generate is stack overflow and we manage the stack ourselves so that's not really going to occur.

Reviewers: RKSimon, spatel

Reviewed By: RKSimon

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D57934

llvm-svn: 353536
2019-02-08 17:07:54 +00:00
Sanjay Patel e9cc26a56a [x86] fix formatting; NFC
(test commit #2 migrating to git)

llvm-svn: 353533
2019-02-08 16:48:40 +00:00
Craig Topper 738180cc7f Fix the lowering issue of intrinsics llvm.localaddress on X86
Patch by Yuanke Luo

Reviewers: craig.topper, annita.zhang, smaslov, rnk, wxiao3

Reviewed By: rnk

Subscribers: efriedma, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D57501

llvm-svn: 353492
2019-02-08 01:14:12 +00:00
Craig Topper c782f18835 [X86] Add FPCW as a register and start using it as an implicit use on floating point instructions.
Summary:
FPCW contains the rounding mode control which we manipulate to implement fp to integer conversion by changing the roudning mode, storing the value to the stack, and then changing the rounding mode back. Because we didn't model FPCW and its dependency chain, other instructions could be scheduled into the middle of the sequence.

This patch introduces the register and adds it as an implciit def of FLDCW and implicit use of the FP binary arithmetic instructions and store instructions. There are more instructions that need to be updated, but this is a good start. I believe this fixes at least the reduced test case from PR40529.

Reviewers: RKSimon, spatel, rnk, efriedma, andrew.w.kaylor

Subscribers: dim, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D57735

llvm-svn: 353489
2019-02-08 00:44:39 +00:00
Sanjay Patel 81f859d169 [x86] fix formatting; NFC
llvm-svn: 353477
2019-02-07 22:36:55 +00:00
Simon Pilgrim fe3ac70b18 [DAGCombiner] (add (umax X, C), -C) --> (usubsat X, C) (PR40111)
Move the (add (umax X, C), -C) --> (usubsat X, C) X86 combine into generic DAGCombiner

First of a number of saturated arithmetic folds that can be moved out of X86-specific code for PR40111.

Differential Revision: https://reviews.llvm.org/D57754

llvm-svn: 353457
2019-02-07 20:14:43 +00:00
Sanjay Patel a5c4a5e958 [x86] split more 256/512-bit shuffles in lowering
This is intentionally a small step because it's hard to know exactly 
where we might introduce a conflicting transform with the code that 
tries to form wider shuffles. But I think this is safe - if we have 
a wide shuffle with 2 operands, then we should do better with an 
extract + narrow shuffle.

Differential Revision: https://reviews.llvm.org/D57867

llvm-svn: 353427
2019-02-07 17:10:49 +00:00
Nirav Dave 84e5bf0c95 [X86] Simplify casing. NFC.
llvm-svn: 353417
2019-02-07 15:43:40 +00:00
Nirav Dave c6bfa103a5 [X86][DAG] Avoid creating dangling bitcast.
combineExtractWithShuffle may leave a dangling bitcast which may
prevent further optimization in later passes. Avoid constructing it
unless it is used.

llvm-svn: 353333
2019-02-06 19:45:47 +00:00
Nirav Dave e5c37958f9 [InlineAsm][X86] Add backend support for X86 flag output parameters.
Allow custom handling of inline assembly output parameters and add X86
flag parameter support.

llvm-svn: 353307
2019-02-06 15:26:29 +00:00
Sanjay Patel e84fbb67a1 [x86] vectorize cast ops in lowering to avoid register file transfers
The proposal in D56796 may cross the line because we're trying to avoid vectorization 
transforms in generic DAG combining. So this is an alternate, later, x86-specific 
translation of that patch.

There are several potential follow-ups to enhance this:
1. Allow extraction from non-zero element index.
2. Peek through extends of smaller width integers.
3. Support x86-specific conversion opcodes like X86ISD::CVTSI2P

Differential Revision: https://reviews.llvm.org/D56864

llvm-svn: 353302
2019-02-06 14:59:39 +00:00
Simon Pilgrim b0afc69435 [X86][SSE] Disable ZERO_EXTEND shuffle combining
rL352997 enabled ZERO_EXTEND from non-shuffle-able value types. I've disabled it for now to fix a regression identified by @asbirlea until I can fix this properly.

llvm-svn: 353198
2019-02-05 19:15:48 +00:00
Simon Pilgrim 822d2e35e7 [X86][AVX] Attempt to combine shuffles to subvector broadcast load
llvm-svn: 353189
2019-02-05 17:02:49 +00:00
Simon Pilgrim 62af24cc93 [X86][SSE] Add SimplifyDemandedVectorElts support for X86ISD::BLENDV
llvm-svn: 353165
2019-02-05 12:27:29 +00:00
Simon Pilgrim 9e595e3663 [X86][AVX] Attempt to share broadcasts of different widths (PR39454)
If we have broadcasts of different vector widths, keep the longest vector width and extract subvectors for the shorter vectors (which should be free).

Differential Revision: https://reviews.llvm.org/D57663

llvm-svn: 353154
2019-02-05 10:58:43 +00:00
Craig Topper f86eb00f12 [X86] Connect the default fpsr and dirflag clobbers in inline assembly to the registers we have defined for them.
Summary:
We don't currently map these constraints to physical register numbers so they don't make it to the MachineIR representation of inline assembly.

This could have problems for proper dependency tracking in the machine schedulers though I don't have a test case that shows that.

Reviewers: rnk

Reviewed By: rnk

Subscribers: eraman, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D57641

llvm-svn: 353141
2019-02-05 06:13:06 +00:00
Roman Lebedev b7ecc9b624 [X86] X86DAGToDAGISel::matchBitExtract(): prepare 'control' in 32 bits
Summary:
Noticed while looking at D56052.
```
  // The 'control' of BEXTR has the pattern of:
  // [15...8 bit][ 7...0 bit] location
  // [ bit count][     shift] name
  // I.e. 0b000000011'00000001 means  (x >> 0b1) & 0b11
```
I.e. we do not care about any of the bits aside from the low 16 bits.
So there is no point in doing the `slh`,`or` in 64 bits,
let's just do everything in 32 bits, and anyext if needed.

We could do that in 16 even, but we intentionally don't
zext to i16 (longer encoding IIRC),
so i'm guessing the same applies here.

Reviewers: craig.topper, andreadb, RKSimon

Reviewed By: craig.topper

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D56715

llvm-svn: 353073
2019-02-04 19:04:26 +00:00
Craig Topper 8ea72a8201 [X86] Add ST0 as an implicit def/use of x87 load/store instructions during FP stackifying.
These instructions implicitly operate on ST0, but we don't currently add that information to the MachineInstr. We also don't add it the tablegen definitions either.

For the most part this doesn't cause any problems because the stackifying occurs after register allocation. All the instructions are marked as having side effects so the postRA scheduler won't reorder them amongst themselves.

But nothing stops inline assembly using X87 instructions from being reordered around other x87 instructions if that inline assembly wasn't marked volatile.

The two test cases I've identified so far in PR40539 involve loads and stores used to set up the inline assembly or capture the results of the inline assembly ending up in the wrong order.

This patch adds implicit ST0 uses/defs to the load/store instructions to prevent this from happening.

I plan to fix all of the FP instructions, but the binops are bit trickier to get right. So I've chosen fixing the known test cases as a good first step.

I think we also need to update the tablegen descriptions so MS inline assembly infers the right clobbers, but I haven't checked that yet.

Differential Revision: https://reviews.llvm.org/D57644

llvm-svn: 353070
2019-02-04 18:43:55 +00:00
Craig Topper bf7593ec4a [X86] Print all register forms of x87 fadd/fsub/fdiv/fmul as having two arguments where on is %st.
All of these instructions consume one encoded register and the other register is %st. They either write the result to %st or the encoded register. Previously we printed both arguments when the encoded register was written. And we printed one argument when the result was written to %st. For the stack popping forms the encoded register is always the destination and we didn't print both operands. This was inconsistent with gcc and objdump and just makes the output assembly code harder to read.

This patch changes things to always print both operands making us consistent with gcc and objdump. The parser should still be able to handle the single register forms just as it did before. This also matches the GNU assembler behavior.

llvm-svn: 353061
2019-02-04 17:28:18 +00:00
Simon Pilgrim 6e5350a367 [X86][SSE] SimplifyDemandedBitsForTargetNode - PCMPGT(0,X) sign mask
For PCMPGT(0, X) patterns where we only demand the sign bit (e.g. BLENDV or MOVMSK) then we can use X directly.

Differential Revision: https://reviews.llvm.org/D57667

llvm-svn: 353051
2019-02-04 15:43:36 +00:00
Andrea Di Biagio edbf06a767 [AsmPrinter] Remove hidden flag -print-schedule.
This patch removes hidden codegen flag -print-schedule effectively reverting the
logic originally committed as r300311
(https://llvm.org/viewvc/llvm-project?view=revision&revision=300311).

Flag -print-schedule was originally introduced by r300311 to address PR32216
(https://bugs.llvm.org/show_bug.cgi?id=32216). That bug was about adding "Better
testing of schedule model instruction latencies/throughputs".

These days, we can use llvm-mca to test scheduling models. So there is no longer
a need for flag -print-schedule in LLVM. The main use case for PR32216 is
now addressed by llvm-mca.
Flag -print-schedule is mainly used for debugging purposes, and it is only
actually used by x86 specific tests. We already have extensive (latency and
throughput) tests under "test/tools/llvm-mca" for X86 processor models. That
means, most (if not all) existing -print-schedule tests for X86 are redundant.

When flag -print-schedule was first added to LLVM, several files had to be
modified; a few APIs gained new arguments (see for example method
MCAsmStreamer::EmitInstruction), and MCSubtargetInfo/TargetSubtargetInfo gained
a couple of getSchedInfoStr() methods.

Method getSchedInfoStr() had to originally work for both MCInst and
MachineInstr. The original implmentation of getSchedInfoStr() introduced a
subtle layering violation (reported as PR37160 and then fixed/worked-around by
r330615).
In retrospect, that new API could have been designed more optimally. We can
always query MCSchedModel to get the latency and throughput. More importantly,
the "sched-info" string should not have been generated by the subtarget.
Note, r317782 fixed an issue where "print-schedule" didn't work very well in the
presence of inline assembly. That commit is also reverted by this change.

Differential Revision: https://reviews.llvm.org/D57244

llvm-svn: 353043
2019-02-04 12:51:26 +00:00
Simon Pilgrim 9899967464 Use auto for dyn_cast case to save a line. NFCI.
llvm-svn: 353041
2019-02-04 12:32:39 +00:00
Craig Topper b5e945c260 Recommit r352660 "[X86] Mark EMMS and FEMMS as clobbering MM0-7 and ST0-7."
We now print ST0 as 'st' when generating the clobber list for MS inline assembly in clang. This matches what the gcc reg name list expects.

Original commit message:

This fixes the test case in PR35982 by preventing MMX instructions that read MM0-7 from being moved below EMMS/FEMMS by the post RA scheduler.

Though as discussed in bugzilla, this is not a complete fix. There is still the possibility of reordering in IR or by the pre-RA scheduler.

Differential Revision: https://reviews.llvm.org/D57298

llvm-svn: 353016
2019-02-04 04:44:20 +00:00
Craig Topper 7a2944efe1 [X86] Print %st(0) as %st when its implicit to the instruction. Continue printing it as %st(0) when its encoded in the instruction.
This is a step back from the change I made in r352985. This appears to be more consistent with gcc and objdump behavior.

llvm-svn: 353015
2019-02-04 04:15:10 +00:00
Craig Topper f77b858dc3 Revert r352985 "[X86] Print %st(0) as %st to match what gcc inline asm uses as the clobber name to make MS inline asm work correctly"
Looking into gcc and objdump behavior more this was overly aggressive. If the register is encoded in the instruction we should print %st(0), if its implicit we should print %st.

I'll be making a more directed change in a future patch.

llvm-svn: 353013
2019-02-04 04:15:02 +00:00
Simon Pilgrim 1fce5a8b75 [X86][AVX] Support shuffle combining for VBROADCAST with smaller vector sources
getTargetShuffleMask can only do this safely if we're extracting the lowest subvector from a vector of the same result type.

llvm-svn: 352999
2019-02-03 16:51:33 +00:00
Simon Pilgrim 18b73a655b [X86][AVX] Support shuffle combining for VPMOVZX with smaller vector sources
llvm-svn: 352997
2019-02-03 16:10:18 +00:00
Simon Pilgrim a2a3e5b811 [X86][AVX] More aggressively simplify BROADCAST source operand
Aim to use scalar source or lowest 128-bit vector directly.

We're still missing some VZMOVL_LOAD combines.

llvm-svn: 352994
2019-02-03 14:39:41 +00:00
Craig Topper 5a570dd437 [X86] Print %st(0) as %st to match what gcc inline asm uses as the clobber name to make MS inline asm work correctly
Summary:
When calculating clobbers for MS style inline assembly we fail if the asm clobbers stack top because we print st(0) and try to pass it through the gcc register name check. This was found with when I attempted to make a emms/femms clobber all ST registers. If you use emms/femms in MS inline asm we would try to use st(0) as the clobber name but clang would think that wasn't a valid clobber name.

This also matches what objdump disassembly prints. It's also what is printed by gcc -S.

Reviewers: RKSimon, rnk, efriedma, spatel, andreadb, lebedev.ri

Reviewed By: rnk

Subscribers: eraman, gbedwell, lebedev.ri, llvm-commits

Differential Revision: https://reviews.llvm.org/D57621

llvm-svn: 352985
2019-02-03 07:53:39 +00:00
Craig Topper 950ca192f6 [X86] Lower ISD::UADDO to use the Z flag instead of C flag when the RHS is a constant 1 to encourage INC formation.
Summary:
Add an additional combine to combineCarryThroughADD to reverse it back to the C flag to avoid regressions.

I believe this catches the cases that D57547 got.

Reviewers: RKSimon, spatel

Reviewed By: spatel

Subscribers: javed.absar, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D57637

llvm-svn: 352984
2019-02-03 07:25:06 +00:00
Simon Pilgrim dbf302c9f1 [X86][AVX] Enable INSERT_SUBVECTOR(SRC0, SHUFFLE(SRC1)) shuffle combining
Push the insert_subvector up through the shuffle operands to help find more cross-lane shuffles.

The is exposes a couple of minor issues that will be fixed shortly:
Missed broadcast folds - we have a mixture of vzext_load lengths that need cleaning up
combine-sdiv.ll - AVX1 SimplifyDemandedVectorElts failure (hits max depth due to a couple of extra bitcasts).

llvm-svn: 352963
2019-02-02 18:08:04 +00:00
Simon Pilgrim bd42f97946 [SDAG] Add SDNode/SDValue getConstantOperandAPInt helper. NFCI.
We already have the getConstantOperandVal helper which returns a uint64_t, but along comes the fuzzer and inserts a i128 -1 constant or something and the whole thing asserts.......

I've updated a few obvious cases, and tried to make use of the const reference where possible, but there's more to do. A number of existing oss-fuzz tickets should be fixed if we start using APInt and perform value clamping where necessary.

llvm-svn: 352961
2019-02-02 17:35:06 +00:00
Simon Pilgrim e95550f508 [X86][AVX] Add VMOVDDUP-VPBROADCASTQ execution domain mapping
Noticed in D57514.

Differential Revision: https://reviews.llvm.org/D57519

llvm-svn: 352922
2019-02-01 21:41:30 +00:00
James Y Knight 7716075a17 [opaque pointer types] Pass value type to GetElementPtr creation.
This cleans up all GetElementPtr creation in LLVM to explicitly pass a
value type rather than deriving it from the pointer's element-type.

Differential Revision: https://reviews.llvm.org/D57173

llvm-svn: 352913
2019-02-01 20:44:47 +00:00
James Y Knight 14359ef1b6 [opaque pointer types] Pass value type to LoadInst creation.
This cleans up all LoadInst creation in LLVM to explicitly pass the
value type rather than deriving it from the pointer's element-type.

Differential Revision: https://reviews.llvm.org/D57172

llvm-svn: 352911
2019-02-01 20:44:24 +00:00
James Y Knight 7976eb5838 [opaque pointer types] Pass function types to CallInst creation.
This cleans up all CallInst creation in LLVM to explicitly pass a
function type rather than deriving it from the pointer's element-type.

Differential Revision: https://reviews.llvm.org/D57170

llvm-svn: 352909
2019-02-01 20:43:25 +00:00
Simon Pilgrim 85184017e9 [X86][SSE] Use PSLLDQ/PSRLDQ to mask out zeroable ends of a shuffle
As suggested on PR40318, this patch uses PSLLDQ/PSRLDQ to lower shuffles to zero out the ends of a vector, leaving a sequential inner section.

For pre-SSSE3 we do this for shuffles with zeros at either end (requiring up to 3 shifts), but once PSHUFB is available I've limited this to shuffles with a single zeroable end (2 shifts).

Differential Revision: https://reviews.llvm.org/D56784

llvm-svn: 352883
2019-02-01 16:02:12 +00:00
Simon Pilgrim 1a529f58f9 [X86][AVX] Combine INSERT_SUBVECTOR(SRC0, BITCAST(SHUFFLE(EXTRACT_SUBVECTOR(SRC1)))
Enable peeking through one use bitcasts to the subvector shuffle.

This still depends on the subvector being the same scalar-size but D57514 has already helped with the more tricky patterns

llvm-svn: 352879
2019-02-01 15:31:01 +00:00
Roman Lebedev 7857215f8e [X86][BdVer2] Transfer delays from the integer to the floating point unit.
Summary:
I'm unable to find this number in the "AMD SOG for family 15h".
llvm-exegesis measures the latencies of these instructions as `2`,
which matches the latencies specified in "AMD SOG for family 15h".

However if we look at Agner, Microarchitecture, "AMD Bulldozer, Piledriver,
Steamroller and Excavator pipeline", "Data delay between different execution
domains", the int->ivec transfer is listed as `8`..`10`cy of additional latency.

Also, Agner's "Instruction tables", for Piledriver, lists their latencies as `12`,
which is consistent with `2cy` from exegesis / AMD SOG + `10cy` transfer delay.

Additional data point comes from the fact that Agner's "Instruction tables",
for Jaguar, lists their latencies as `8`; and "AMD SOG for family 16h" does
state the `+6cy` int->ivec delay, which is consistent with instr latency of `1` or `2`.

Reviewers: andreadb, RKSimon, craig.topper

Reviewed By: andreadb

Subscribers: gbedwell, courbet, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D57300

llvm-svn: 352861
2019-02-01 11:15:13 +00:00
James Y Knight 13680223b9 [opaque pointer types] Add a FunctionCallee wrapper type, and use it.
Recommit r352791 after tweaking DerivedTypes.h slightly, so that gcc
doesn't choke on it, hopefully.

Original Message:
The FunctionCallee type is effectively a {FunctionType*,Value*} pair,
and is a useful convenience to enable code to continue passing the
result of getOrInsertFunction() through to EmitCall, even once pointer
types lose their pointee-type.

Then:
- update the CallInst/InvokeInst instruction creation functions to
  take a Callee,
- modify getOrInsertFunction to return FunctionCallee, and
- update all callers appropriately.

One area of particular note is the change to the sanitizer
code. Previously, they had been casting the result of
`getOrInsertFunction` to a `Function*` via
`checkSanitizerInterfaceFunction`, and storing that. That would report
an error if someone had already inserted a function declaraction with
a mismatching signature.

However, in general, LLVM allows for such mismatches, as
`getOrInsertFunction` will automatically insert a bitcast if
needed. As part of this cleanup, cause the sanitizer code to do the
same. (It will call its functions using the expected signature,
however they may have been declared.)

Finally, in a small number of locations, callers of
`getOrInsertFunction` actually were expecting/requiring that a brand
new function was being created. In such cases, I've switched them to
Function::Create instead.

Differential Revision: https://reviews.llvm.org/D57315

llvm-svn: 352827
2019-02-01 02:28:03 +00:00
James Y Knight fadf25068e Revert "[opaque pointer types] Add a FunctionCallee wrapper type, and use it."
This reverts commit f47d6b38c7 (r352791).

Seems to run into compilation failures with GCC (but not clang, where
I tested it). Reverting while I investigate.

llvm-svn: 352800
2019-01-31 21:51:58 +00:00
James Y Knight f47d6b38c7 [opaque pointer types] Add a FunctionCallee wrapper type, and use it.
The FunctionCallee type is effectively a {FunctionType*,Value*} pair,
and is a useful convenience to enable code to continue passing the
result of getOrInsertFunction() through to EmitCall, even once pointer
types lose their pointee-type.

Then:
- update the CallInst/InvokeInst instruction creation functions to
  take a Callee,
- modify getOrInsertFunction to return FunctionCallee, and
- update all callers appropriately.

One area of particular note is the change to the sanitizer
code. Previously, they had been casting the result of
`getOrInsertFunction` to a `Function*` via
`checkSanitizerInterfaceFunction`, and storing that. That would report
an error if someone had already inserted a function declaraction with
a mismatching signature.

However, in general, LLVM allows for such mismatches, as
`getOrInsertFunction` will automatically insert a bitcast if
needed. As part of this cleanup, cause the sanitizer code to do the
same. (It will call its functions using the expected signature,
however they may have been declared.)

Finally, in a small number of locations, callers of
`getOrInsertFunction` actually were expecting/requiring that a brand
new function was being created. In such cases, I've switched them to
Function::Create instead.

Differential Revision: https://reviews.llvm.org/D57315

llvm-svn: 352791
2019-01-31 20:35:56 +00:00
Craig Topper a8f0745440 Revert "[X86] Mark EMMS and FEMMS as clobbering MM0-7 and ST0-7."
This is causing a failure in chromium

llvm-svn: 352782
2019-01-31 19:05:22 +00:00
Simon Pilgrim 00cefe1158 Trim trailing whitespace. NFCI.
llvm-svn: 352775
2019-01-31 17:49:25 +00:00
Simon Pilgrim eb6aef6db3 [X86][AVX] Fold concat(broadcast(x),broadcast(x)) -> broadcast(x)
Differential Revision: https://reviews.llvm.org/D57514

llvm-svn: 352774
2019-01-31 17:48:35 +00:00
Simon Pilgrim d04a2d2d5e [X86][AVX] insert_subvector(bitcast(v), bitcast(s), c1) -> bitcast(insert_subvector(v,s,c2))
Similar to what we already do in DAGCombiner, but this version also handles bitcasts from types with different scalar sizes, which x86 is better at handling.

Differential Revision: https://reviews.llvm.org/D57514

llvm-svn: 352773
2019-01-31 17:38:10 +00:00
Simon Pilgrim 63f3383ece [X86][AVX] Fold broadcast(bitcast(src)) -> bitcast(broadcast(src))
llvm-svn: 352751
2019-01-31 14:04:07 +00:00
Simon Pilgrim a001008a09 [X86] combineExtractWithShuffle - more aggressively peek through bitcasts
Fixes regression introduced by rL352743

llvm-svn: 352745
2019-01-31 11:55:30 +00:00
Simon Pilgrim b96a2c7fed [X86][AVX] Enable AVX1 broadcasts in shuffle combining
Enables 32/64-bit scalar load broadcasts on AVX1 targets

The extractelement-load.ll regression will be fixed shortly in a followup commit.

llvm-svn: 352743
2019-01-31 11:41:10 +00:00
Simon Pilgrim 51c2efc104 [X86][AVX] Fold vt1 concat_vectors(vt2 undef, vt2 broadcast(x)) --> vt1 broadcast(x)
If we're not inserting the broadcast into the lowest subvector then we can avoid the insertion by just performing a larger broadcast.

Avoids a regression when we enable AVX1 broadcasts in shuffle combining

llvm-svn: 352742
2019-01-31 11:15:05 +00:00
Sjoerd Meijer f7cc34cae8 [SelectionDAG] Codesize: don't expand SHIFT to SHIFT_PARTS
And instead just generate a libcall. My motivating example on ARM was a simple:
  
  shl i64 %A, %B

for which the code bloat is quite significant. For other targets that also
accept __int128/i128 such as AArch64 and X86, it is also beneficial for these
cases to generate a libcall when optimising for minsize. On these 64-bit targets,
the 64-bits shifts are of course unaffected because the SHIFT/SHIFT_PARTS
lowering operation action is not set to custom/expand.

Differential Revision: https://reviews.llvm.org/D57386

llvm-svn: 352736
2019-01-31 08:07:30 +00:00
Matt Arsenault 2a64598ef2 GlobalISel: Fix creating MMOs with align 0
llvm-svn: 352712
2019-01-31 01:38:47 +00:00
Craig Topper 8bdc203d4b [X86] Remove handling of ISD::INTRINSIC_WO_CHAIN in ReplaceNodeResults.
I believe this was there to handle avx512bw intrinsics that returned i64 type in 32-bit mode. But all those intrinsics have since been changed to v64i1 results or replaced with generic IR.

llvm-svn: 352698
2019-01-31 00:04:46 +00:00
Craig Topper 22b3de5b51 [X86] Mark EMMS and FEMMS as clobbering MM0-7 and ST0-7.
This fixes the test case in PR35982 by preventing MMX instructions that read MM0-7 from being moved below EMMS/FEMMS by the post RA scheduler.

Though as discussed in bugzilla, this is not a complete fix. There is still the possibility of reordering in IR or by the pre-RA scheduler.

Differential Revision: https://reviews.llvm.org/D57298

llvm-svn: 352660
2019-01-30 19:57:01 +00:00
Simon Pilgrim 317fad5921 [X86][AVX] Prefer to combine shuffle to broadcasts whenever possible
This is the first step towards improving broadcast support on AVX1 targets.

llvm-svn: 352634
2019-01-30 16:19:19 +00:00
Craig Topper 11133d2531 [X86] Remove unnecessary code from the top of handleCompareFP in X86FloatingPoint.cpp.
There were checks to ensure some tables were sorted, but those tables aren't used by this function. The same tables are checked in the function that does use them. Maybe this was copy/pasted?

llvm-svn: 352609
2019-01-30 08:04:06 +00:00
Craig Topper 594f76aea2 [X86] Remove a couple places where we unnecessarily pass 0 to the EmitPriority of some FP instruction aliases. NFC
As far as I can tell we already won't emit these aliases due to an operand count check in the tablegen code. Removing these because I couldn't make sense of the inconsistency between fadd and fmul from reading the code.

I checked the AsmMatcher and AsmWriter files before and after this change and there were no differences.

llvm-svn: 352608
2019-01-30 07:33:24 +00:00
Craig Topper 9dfe9b086e [X86] Add FPSW as a Def on some FP instructions that were missing it.
llvm-svn: 352607
2019-01-30 07:08:44 +00:00
Andrea Di Biagio 815cdbff29 [X86][Btver2] Improved latency/throughput model for scalar int-to-float conversions.
Account for bypass delays when computing the latency of scalar int-to-float
conversions.
On Jaguar we need to account for an extra 6cy latency (see AMD fam16h SOG).
This patch also fixes the number of micropcodes for the register-memory variants
of scalar int-to-float conversions.

Differential Revision: https://reviews.llvm.org/D57148

llvm-svn: 352518
2019-01-29 16:47:27 +00:00
Mikael Holmen b792627ce9 Fix compiler warning when using clang 3.6.0
Without the fix we get the following (with -Werror):

../lib/Target/X86/X86ISelLowering.cpp:14181:58: error: suggest braces around initialization of subobject [-Werror,-Wmissing-braces]
  SmallVector<std::array<int, 2>, 2> LaneSrcs(NumLanes, {-1, -1});
                                                         ^~~~~~
                                                         {     }
1 error generated.

llvm-svn: 352455
2019-01-29 06:51:28 +00:00
Craig Topper 390ac61b93 Recommit r352255 "[SelectionDAG][X86] Don't use SEXTLOAD for promoting masked loads in the type legalizer"
This did not cause the buildbot failure it was previously reverted for.

Original commit message:

I'm not sure why we were using SEXTLOAD. EXTLOAD seems more appropriate since we don't care about the upper bits.

This patch changes this and then modifies the X86 post legalization combine to emit a extending shuffle instead of a sign_extend_vector_inreg. Could maybe use an any_extend_vector_inre

On AVX512 targets I think we might be able to use a masked vpmovzx and not have to expand this at all.

llvm-svn: 352433
2019-01-28 21:38:47 +00:00
Nikita Popov 8e1a464e6a [CodeGen][X86] Expand UADDSAT to NOT+UMIN+ADD
Followup to D56636, this time handling the UADDSAT case by expanding
uadd.sat(a, b) to umin(a, ~b) + b.

Differential Revision: https://reviews.llvm.org/D56869

llvm-svn: 352409
2019-01-28 19:19:09 +00:00
Simon Pilgrim 2c17512456 [X86][AVX] Remove lowerShuffleByMerging128BitLanes 2-lane restriction
First step towards adding support for 64-bit unary "sublane" handling (a bit like lowerShuffleAsRepeatedMaskAndLanePermute). 

This allows us to add lowerV64I8Shuffle handling.

llvm-svn: 352389
2019-01-28 17:02:35 +00:00
Sanjay Patel 94cca60b82 [x86] allow more shuffle splitting to avoid vpermps (PR40434)
This is tricky to make optimal: sometimes we're better off using 
a single wider op, but other times it makes more sense to combine
a narrow ops to achieve the same result.

This solves the case from:
https://bugs.llvm.org/show_bug.cgi?id=40434

There's potentially a similar change for vectors with 64-bit elements,
but it needs adjustments similar to rL352333 to avoid creating infinite
loops.

llvm-svn: 352380
2019-01-28 15:51:34 +00:00
Craig Topper 453150bc18 [X86] Add new variadic avx512 compress/expand intrinsics that use vXi1 types for the mask argument.
Remove and autoupgrade the old intrinsics

llvm-svn: 352343
2019-01-28 07:03:03 +00:00
Sanjay Patel ebe6b43aec [x86] add restriction for lowering to vpermps
This transform was added with rL351346, and we had
an escape for shufps, but we also want one for
unpckps vs. vpermps because vpermps doesn't take
an immediate shuffle index operand.

llvm-svn: 352333
2019-01-27 21:53:33 +00:00
Simon Pilgrim 670a6971f8 [X86][SSE] Add UNDEF handling to combineSelect ISD::USUBSAT matching (PR40083)
llvm-svn: 352330
2019-01-27 21:01:23 +00:00
Simon Pilgrim f10b6623cc [X86][SSE] Permit UNDEFs in combineAddToSUBUS matching (PR40083)
llvm-svn: 352328
2019-01-27 20:36:37 +00:00
Sanjay Patel 5f1fdaa192 [x86] refactor logic in lowerShuffleWithUndefHalf
Although this is longer code, this is no-functional-change-intended.
The goal is to untangle the conditions under which we bail out, so 
that's easier to adjust.

llvm-svn: 352320
2019-01-27 18:12:03 +00:00
Gabor Buella a0f743b77a [X86] Add some missing blsr patterns
The add+and sequence followed by a branch can
happen e.g. when looping over the set bits of an integer:

```
while (x != 0) {
   func(x & ~x);
   x &= x - 1;
}
```

Reviewed By: ctopper

Differential Revision: https://reviews.llvm.org/D57296

llvm-svn: 352306
2019-01-27 06:15:39 +00:00
Craig Topper e65d4c5525 [X86] Add a pattern for (i64 (and (anyext def32:), 0x00000000FFFFFFFF)) to produce SUBREG_TO_REG
def32 here means the producing instruction zeroed bits 63:32. We already do this for zext, but it looks like we can get an and+anyext sometimes.

Spotted in the diffs from D33587.

llvm-svn: 352303
2019-01-27 03:37:05 +00:00
Simon Pilgrim a914fa4dd8 [X86] combineAddOrSubToADCOrSBB/combineCarryThroughADD - use oneuse for entire SDNode
Fix issue noted in D57281 that only tested the one use for the SDValue (the result flag), not the entire SUB.

I've added the getNode() to make it clearer what is intended than just the -> redirection.

llvm-svn: 352291
2019-01-26 21:29:16 +00:00
Simon Pilgrim 37a8e65a60 [X86] combineCarryThroughADD - add support for X86::COND_A commutations (PR24545)
As discussed on PR24545, we should try to commute X86::COND_A 'icmp ugt' cases to X86::COND_B 'icmp ult' to more optimally bind the carry flag output to a SBB instruction.

Differential Revision: https://reviews.llvm.org/D57281

llvm-svn: 352289
2019-01-26 20:23:04 +00:00
Simon Pilgrim b7a15acd38 [X86] Fold X86ISD::SBB(ISD::SUB(X,Y),0) -> X86ISD::SBB(X,Y) (PR25858)
We often generate X86ISD::SBB(X, 0) for carry flag arithmetic.

I had tried to create test cases for the ADC equivalent (which often uses the same pattern) but haven't managed to find anything yet.

Differential Revision: https://reviews.llvm.org/D57169

llvm-svn: 352288
2019-01-26 20:13:44 +00:00
Simon Pilgrim 6162fba57c [X86][SSE] Generalized unsigned compares to support nonsplat constant vectors (PR39859)
llvm-svn: 352283
2019-01-26 16:40:03 +00:00
Sanjay Patel a03c63b77f [x86] add helper for creating a half-width shuffle; NFC
This reduces a bit of duplication between the combining and
lowering places that use it, but the primary motivation is
to make it easier to rearrange the lowering logic and solve
PR40434:
https://bugs.llvm.org/show_bug.cgi?id=40434

llvm-svn: 352280
2019-01-26 16:20:22 +00:00
Craig Topper 3b5e01b386 [X86] Remove and autoupgrade vpconflict intrinsics that take a mask and passthru argument.
We have unmasked versions as of r352172

llvm-svn: 352270
2019-01-26 06:27:01 +00:00
Craig Topper 58e6b37e62 Revert r352255 "[SelectionDAG][X86] Don't use SEXTLOAD for promoting masked loads in the type legalizer"
This might be breaking an lldb windows buildbot.

llvm-svn: 352268
2019-01-26 02:44:58 +00:00
Craig Topper 6c9c7d0796 [X86] Remove GCCBuiltins from 512-bit cvt(u)qqtops, cvt(u)qqtopd, and cvt(u)dqtops intrinsics. Add new variadic uitofp/sitofp with rounding mode intrinsics.
Summary: See clang patch D56998 for a full description.

Reviewers: RKSimon, spatel

Reviewed By: RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D56999

llvm-svn: 352266
2019-01-26 02:41:54 +00:00
Craig Topper 7a8e74775c [X86] Add DAG combine to merge vzext_movl with the various fp<->int conversion operations that only write the lower 64-bits of an xmm register and zero the rest.
Summary: We have isel patterns for this, but we're missing some load patterns and all broadcast patterns. A DAG combine seems like a better fit for this.

Reviewers: RKSimon, spatel

Reviewed By: RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D56971

llvm-svn: 352260
2019-01-26 01:17:09 +00:00
Craig Topper b1d3457c03 [SelectionDAG][X86] Don't use SEXTLOAD for promoting masked loads in the type legalizer
Summary:
I'm not sure why we were using SEXTLOAD. EXTLOAD seems more appropriate since we don't care about the upper bits.

This patch changes this and then modifies the X86 post legalization combine to emit a extending shuffle instead of a sign_extend_vector_inreg. Could maybe use an any_extend_vector_inreg, but I just did what we already do in LowerLoad. I think we can actually get rid of this code entirely if we switch to -x86-experimental-vector-widening-legalization.

On AVX512 targets I think we might be able to use a masked vpmovzx and not have to expand this at all.

Reviewers: RKSimon, spatel

Reviewed By: RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D57186

llvm-svn: 352255
2019-01-26 00:26:37 +00:00
Mircea Trofin 519f42d914 [llvm] Opt-in flag for X86DiscriminateMemOps
Summary:
Currently, if an instruction with a memory operand has no debug information,
X86DiscriminateMemOps will generate one based on the first line of the
enclosing function, or the last seen debug info.

This may cause confusion in certain debugging scenarios. The long term
approach would be to use the line number '0' in such cases, however, that
brings in challenges: the base discriminator value range is limited
(4096 values).

For the short term, adding an opt-in flag for this feature.

See bug 40319 (https://bugs.llvm.org/show_bug.cgi?id=40319)

Reviewers: dblaikie, jmorse, gbedwell

Reviewed By: dblaikie

Subscribers: aprantl, eraman, hiraditya

Differential Revision: https://reviews.llvm.org/D57257

llvm-svn: 352246
2019-01-25 21:49:54 +00:00
Craig Topper 4cf28bad5b [X86] Combine masked store and truncate into masked truncating stores.
We also need to combine to masked truncating with saturation stores, but I'm leaving that for a future patch.

This does regress some tests that used truncate wtih saturation followed by a masked store. Those now use a truncating store and use min/max to saturate.

Differential Revision: https://reviews.llvm.org/D57218

llvm-svn: 352230
2019-01-25 18:37:36 +00:00
Sanjay Patel 0020f8bb23 [x86] simplify logic in lowerShuffleWithUndefHalf(); NFCI
This seems unnecessarily complicated because we gave names to
opposite polarity bools and have code comments that don't really
line up with the logic. 

Step 1: remove UndefUpper and assert that it is the opposite of 
UndefLower after the initial early exit.

llvm-svn: 352217
2019-01-25 17:00:41 +00:00
Simon Pilgrim f56298f4b9 [X86] Simplify X86ISD::ADD/SUB if we don't use the result flag
Simplify to the generic ISD::ADD/SUB if we don't make use of the result flag.

This mainly helps with ADDCARRY/SUBBORROW intrinsics which get expanded to X86ISD::ADD/SUB but could be simplified further.

Noticed in some of the test cases in PR31754

Differential Revision: https://reviews.llvm.org/D57234

llvm-svn: 352210
2019-01-25 15:58:28 +00:00
Sanjay Patel 21aa6ddc14 [x86] narrow a shuffle that doesn't use or set any high elements
This isn't the final fix for our reduction/horizontal codegen, but it takes care 
of a lot of the problems. After we narrow the shuffle, existing combines for 
insert/extract and binops kick in, and we end up with cheaper 128-bit ops.

The avg and mul reduction tests show an existing shuffle lowering hole for 
AVX2/AVX512. I think in its most minimal form this is:
https://bugs.llvm.org/show_bug.cgi?id=40434
...but we might need multiple fixes to get it right.

Differential Revision: https://reviews.llvm.org/D57156

llvm-svn: 352209
2019-01-25 15:37:42 +00:00
Craig Topper 6fd9af587a [X86] Add non-masked versions of vpconflict intrinsics so we can use a select in the header file in clang.
I'll remove and autoupgrade the old intrinsics in a future commit.

llvm-svn: 352172
2019-01-25 07:08:07 +00:00
Sanjay Patel 4c304b2923 [x86] move half-size shuffle mask creation to helper; NFC
As noted in D57156, we want to check at least part of
this pattern earlier (in combining), so this will allow
the code to be shared instead of duplicated.

llvm-svn: 352127
2019-01-24 23:12:36 +00:00
Sanjay Patel e524639d72 [x86] rename VectorShuffle -> Shuffle; NFC
This wasn't consistent within the file, so made it harder to search.
Standardize on the shorter name to save some typing.

llvm-svn: 352077
2019-01-24 18:52:12 +00:00
James Y Knight 2c36240a82 Fix emission of _fltused for MSVC.
It should be emitted when any floating-point operations (including
calls) are present in the object, not just when calls to printf/scanf
with floating point args are made.

The difference caused by this is very subtle: in static (/MT) builds,
on x86-32, in a program that uses floating point but doesn't print it,
the default x87 rounding mode may not be set properly upon
initialization.

This commit also removes the walk of the types pointed to by pointer
arguments in calls. (To assist in opaque pointer types migration --
eventually the pointee type won't be available.)

That latter implies that it will no longer consider a call like
`scanf("%f", &floatvar)` as sufficient to emit _fltused on its
own. And without _fltused, `scanf("%f")` will abort with error R6002. This
new behavior is unlikely to bite anyone in practice (you'd have to
read a float, and do nothing with it!), and also, is consistent with
MSVC.

Differential Revision: https://reviews.llvm.org/D56548

llvm-svn: 352076
2019-01-24 18:34:00 +00:00
Sanjay Patel e5a0bcf7b8 [x86] add low/high undef half shuffle mask helpers; NFC
This is the most common usage for isUndefInRange, 
so make the code slightly less duplicated and more 
readable.

llvm-svn: 352063
2019-01-24 17:05:02 +00:00
Nirav Dave c5cb2bed58 [X86] Add missing isReg() guards in FixupSetCCs pass.
llvm-svn: 352051
2019-01-24 15:04:17 +00:00
Simon Pilgrim 47ca8606ba [TTI] Add generic SADDO/SSUBO costs
Added x86 scalar sadd_with_overflow/ssub_with_overflow costs.

llvm-svn: 352045
2019-01-24 13:36:45 +00:00
Simon Pilgrim 2d1964b90f [TTI] Add generic UADDO/USUBO costs
Added x86 scalar uadd_with_overflow/usub_with_overflow costs.

Differential Revision: https://reviews.llvm.org/D56907

llvm-svn: 352043
2019-01-24 12:10:20 +00:00
Craig Topper e79b779fbb [X86] Add test cases for opportunities to fold a truncate and a masked store into a truncating masked store.
llvm-svn: 352027
2019-01-24 06:15:03 +00:00
Andrea Di Biagio d768d35515 [MC][X86] Correctly model additional operand latency caused by transfer delays from the integer to the floating point unit.
This patch adds a new ReadAdvance definition named ReadInt2Fpu.
ReadInt2Fpu allows x86 scheduling models to accurately describe delays caused by
data transfers from the integer unit to the floating point unit.
ReadInt2Fpu currently defaults to a delay of zero cycles (i.e. no delay) for all
x86 models excluding BtVer2. That means, this patch is only a functional change
for the Jaguar cpu model only.

Tablegen definitions for instructions (V)PINSR* have been updated to account for
the new ReadInt2Fpu. That read is mapped to the the GPR input operand.
On Jaguar, int-to-fpu transfers are modeled as a +6cy delay. Before this patch,
that extra delay was added to the opcode latency. In practice, the insert opcode
only executes for 1cy. Most of the actual latency is actually contributed by the
so-called operand-latency. According to the AMD SOG for family 16h, (V)PINSR*
latency is defined by expression f+1, where f is defined as a forwarding delay
from the integer unit to the fpu.

When printing instruction latency from MCA (see InstructionInfoView.cpp) and LLC
(only when flag -print-schedule is speified), we now need to account for any
extra forwarding delays. We do this by checking if scheduling classes declare
any negative ReadAdvance entries. Quoting a code comment in TargetSchedule.td:
"A negative advance effectively increases latency, which may be used for
cross-domain stalls". When computing the instruction latency for the purpose of
our scheduling tests, we now add any extra delay to the formula. This avoids
regressing existing codegen and mca schedule tests. It comes with the cost of an
extra (but very simple) hook in MCSchedModel.

Differential Revision: https://reviews.llvm.org/D57056

llvm-svn: 351965
2019-01-23 16:35:07 +00:00
Matt Arsenault 30989e492b GlobalISel: Allow shift amount to be a different type
For AMDGPU the shift amount is never 64-bit, and
this needs to use a 32-bit shift.

X86 uses i8, but seemed to be hacking around this before.

llvm-svn: 351882
2019-01-22 21:42:11 +00:00
Matt Arsenault a5840c3c39 Codegen support for atomicrmw fadd/fsub
llvm-svn: 351851
2019-01-22 18:36:06 +00:00
Simon Pilgrim 933673d878 [X86][SSE] Canonicalize OR(AND(X,C),AND(Y,~C)) -> OR(AND(X,C),ANDNP(C,Y))
For constant bit select patterns, replace one AND with a ANDNP, allowing us to reuse the constant mask. Only do this if the mask has multiple uses (to avoid losing load folding) or if we have XOP as its VPCMOV can handle most folding commutations.

This also requires computeKnownBitsForTargetNode support for X86ISD::ANDNP and X86ISD::FOR to prevent regressions in fabs/fcopysign patterns.

Differential Revision: https://reviews.llvm.org/D55935

llvm-svn: 351819
2019-01-22 13:44:49 +00:00
Simon Pilgrim aa6a4339ac [X86][BtVer2] SSE2 vector shifts has local forwarding disabled
Similar to horizontal ops on D56777, the sse2 (but not mmx) bit shift ops has local forwarding disabled, adding +1cy to the use latency for the result.

Differential Revision: https://reviews.llvm.org/D57026

llvm-svn: 351817
2019-01-22 13:27:18 +00:00
Simon Pilgrim 9e2c2cfcd9 Fix "comparison of unsigned expression >= 0 is always true" warning. NFCI.
llvm-svn: 351816
2019-01-22 13:18:26 +00:00
Simon Pilgrim 2c69f90171 [X86][BtVer2] X86ISD::VPERMILPV has local forwarding disabled
Similar to horizontal ops on D56777, the vpermilpd/vpermilps variable mask ops has local forwarding disabled, adding +1cy to the use latency for the result.

Differential Revision: https://reviews.llvm.org/D57022

llvm-svn: 351815
2019-01-22 13:13:57 +00:00
Simon Pilgrim ee900efb30 [CostModel][X86] Add ICMP Predicate specific costs
First step towards PR40376, this patch adds support for getCmpSelInstrCost to use the (optional) Instruction CmpInst predicate to indicate the type of integer comparison we're performing and alter the costs accordingly.

Differential Revision: https://reviews.llvm.org/D57013

llvm-svn: 351810
2019-01-22 12:29:38 +00:00
Simon Pilgrim 180fcff5a7 [X86][SSE] Add selective commutation support for insertps (PR40340)
When we are inserting 1 "inline" element, and zeroing 2 of the other elements then we can safely commute the insertps source inputs to improve memory folding.

Differential Revision: https://reviews.llvm.org/D56843

llvm-svn: 351807
2019-01-22 12:17:48 +00:00
Simon Pilgrim 3adf50b2c0 [X86] HADDPS/HADDPD scalar lowering was added at rL350421
llvm-svn: 351797
2019-01-22 10:49:41 +00:00
Craig Topper bcbdf61078 [X86] Use X86ISD::VFPROUND instead of ISD::FP_ROUND for 256 and 512 bit cvtpd2ps intrinsics.
Summary:
Use X86ISD::VFPROUND in the instruction isel patterns. Add new patterns for ISD::FP_ROUND to maintain support for fptrunc in IR.

In the process I found a couple duplicate isel patterns which I also deleted in this patch.

Reviewers: RKSimon, spatel

Reviewed By: RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D56991

llvm-svn: 351762
2019-01-21 20:14:09 +00:00
Craig Topper c2087d8f3f [X86] Change avx512 COMPRESS and EXPAND lowering to use a single masked node instead of expand/compress+select.
Summary:
For compress, a select node doesn't semantically reflect the behavior of the instruction. The mask would have holes in it, but the resulting write is to contiguous elements at the bottom of the vector.

Furthermore, as far as the compressing and expanding is concerned the behavior is depended on the mask. You can't just have an expand/compress node that only reads the input vector. That node would have no meaning by itself.

This all only works because we pattern match the compress/expand+select back to the instruction. But conceivably an optimization of the select could break the pattern and leave something meaningless.

This patch modifies the expand and compress node to take the mask and passthru as additional inputs and gets rid of the select all together.

Reviewers: RKSimon, spatel

Reviewed By: RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D57002

llvm-svn: 351761
2019-01-21 20:02:28 +00:00
Simon Pilgrim 9b73ae96c5 [X86][BtVer2] Update latency of mmx horizontal operations
D56777 added +1cy local forwarding penalty for horizontal operations, but this penalty only affects sse2/xmm variants, the mmx variants don't suffer the penalty.

Confirmed with @andreadb

llvm-svn: 351755
2019-01-21 18:04:25 +00:00
Andrea Di Biagio b68dd05c14 [X86][BtVer2] Update the WriteLoad latency.
r327630 introduced new write definitions for float/vector loads.
Before that revision, WriteLoad was used by both integer/float (scalar/vector)
load. So, WriteLoad had to conservatively declare a latency to 5cy. That is
because the load-to-use latency for float/vector load is 5cy.

Now that we have dedicated writes for float/vector loads, there is no reason why
we should keep the latency of WriteLoad to 5cy. At the moment, WriteLoad is only
used by scalar integer loads only; we can assume an optimstic 3cy latency for
them.
This patch changes that latency from 5cy to 3cy, and regenerates the affected
scheduling/mca tests.

Differential Revision: https://reviews.llvm.org/D56922

llvm-svn: 351742
2019-01-21 12:04:10 +00:00
Craig Topper f608dc1f57 [X86] Remove and autoupgrade vpmovqd/vpmovwb intrinsics using trunc+select.
llvm-svn: 351729
2019-01-21 08:16:59 +00:00
Simon Pilgrim e1143c1322 [X86] Auto upgrade VPCOM/VPCOMU intrinsics to generic integer comparisons
This causes a couple of changes in the upgrade tests as signed/unsigned eq/ne are equivalent and we constant fold true/false codes, these changes are the same as what we already do for avx512 cmp/ucmp.

Noticed while cleaning up vector integer comparison costs for PR40376.

llvm-svn: 351697
2019-01-20 19:27:40 +00:00
Simon Pilgrim c934d3a01b [CostModel][X86] Add explicit vector select costs
Prior to SSE41 (and sometimes on AVX1), vector select has to be performed as a ((X & C)|(Y & ~C)) bit select.

Exposes a couple of issues with the min/max reduction costs (which only go down to SSE42 for some reason).

The increase pre-SSE41 selection costs also prevent a couple of tests from firing any longer, so I've either tweaked the target or added AVX tests as well to the existing SSE2 tests.

llvm-svn: 351685
2019-01-20 13:55:01 +00:00
Simon Pilgrim 1231904c48 [CostModel][X86] Add explicit fcmp costs for pre-SSE42 targets
Typical throughputs: cmpss/cmpps = 1cy and cmpsd/cmppd = 2cy before the Core2 era

llvm-svn: 351684
2019-01-20 13:21:43 +00:00
Simon Pilgrim bf4b770225 [TTI][X86] Reordered getCmpSelInstrCost cost tables in descending ISA order. NFCI.
Minor tidyup to make it clearer whats going on before adding additional costs.

llvm-svn: 351683
2019-01-20 12:28:13 +00:00
Craig Topper 4aa74fff1f [X86] Add masked MCVTSI2P/MCVTUI2P ISD opcodes to model the cvtqq2ps cvtuqq2ps nodes that produce less than 128-bits of results.
These nodes zero the upper half of the result and can't be represented with vselect.

llvm-svn: 351666
2019-01-19 21:26:20 +00:00
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
Reid Kleckner 38f9900aa5 [X86] Deduplicate static calling convention helpers for code size, NFC
Summary:
Right now we include ${TGT}GenCallingConv.inc once per each instruction
selection method implemented by ${TGT}:
- ${TGT}ISelLowering.cpp
- ${TGT}CallLowering.cpp
- ${TGT}FastISel.cpp

Instead, add a mechanism to tablegen for marking a particular convention
as "External", which causes tablegen to emit into the ::llvm namespace,
instead of as a static helper. This allows us to provide a header to
forward declare it, so we can simply call the function from all the
places it is referenced. Typically the calling convention analyzer is
called indirectly, so it doesn't benefit from inlining.

This saves a bit of final binary size, but mostly just saves object file
size:

before  after   diff   artifact
12852K  12492K  -360K  X86ISelLowering.cpp.obj
4640K   4280K   -360K  X86FastISel.cpp.obj
1704K   2092K   +388K  X86CallingConv.cpp.obj
52448K  52336K  -112K  llc.exe

I didn't collect before numbers for X86CallLowering.cpp.obj, which is
for GlobalISel, but we should save 360K there as well.

This patch applies the strategy to the X86 backend, but there is no
reason it couldn't be applied to the other backends that implement
multiple ISel strategies, like AArch64.

Reviewers: craig.topper, hfinkel, efriedma

Subscribers: javed.absar, kristof.beyls, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D56883

llvm-svn: 351616
2019-01-19 00:33:02 +00:00
Craig Topper 08d3d32ead [X86] Lower avx512f scatter intrinsics to X86MaskedScatterSDNode instead of going directly to MachineSDNode.
This sends these intrinsics through isel in a much more normal way. This should allow addressing mode matching in isel to make better use of the displacement field.

llvm-svn: 351583
2019-01-18 20:14:46 +00:00
Craig Topper b9d4461f9f [X86] Lower avx2/avx512f gather intrinsics to X86MaskedGatherSDNode instead of going directly to MachineSDNode.:
This sends these intrinsics through isel in a much more normal way. This should allow addressing mode matching in isel to make better use of the displacement field.

Differential Revision: https://reviews.llvm.org/D56827

llvm-svn: 351570
2019-01-18 18:22:26 +00:00
Sanjay Patel b6c91a1a59 [x86] simplify code for SDValue.getOperand(); NFC
llvm-svn: 351557
2019-01-18 15:55:21 +00:00
Reid Kleckner ca16e9d8a3 [X86] Sink complex MCU CC helper to .cpp file from .h file, NFC
llvm-svn: 351384
2019-01-16 22:05:36 +00:00
Craig Topper 59abdf5f3f [X86] Add X86ISD::VSHLV and X86ISD::VSRLV nodes for psllv and psrlv
Previously we used ISD::SHL and ISD::SRL to represent these in SelectionDAG. ISD::SHL/SRL interpret an out of range shift amount as undefined behavior and will constant fold to undef. While the intrinsics are defined to return 0 for out of range shift amounts. A previous patch added a special node for VPSRAV to produce all sign bits.

This was previously believed safe because undefs frequently get turned into 0 either from the constant pool or a desire to not have a false register dependency. But undef is treated specially in some optimizations. For example, its ignored in detection of vector splats. So if the ISD::SHL/SRL can be constant folded and all of the elements with in bounds shift amounts are the same, we might fold it to single element broadcast from the constant pool. This would not put 0s in the elements with out of bounds shift amounts.

We do have an existing InstCombine optimization to use shl/lshr when the shift amounts are all constant and in bounds. That should prevent some loss of constant folding from this change.

Patch by zhutianyang and Craig Topper

Differential Revision: https://reviews.llvm.org/D56695

llvm-svn: 351381
2019-01-16 21:46:32 +00:00
Craig Topper 5ea3120718 [X86] Use X86ISD::BLENDV for blendv intrinsics. Replace vselect with blendv just before isel table lookup. Remove vselect isel patterns.
This cleans up the duplication we have with both intrinsic isel patterns and vselect isel patterns. This should also allow the intrinsics to get SimplifyDemandedBits support for the condition.

I've switched the canonical pattern in isel to use the X86ISD::BLENDV node instead of VSELECT. Since it always seemed weird to move from BLENDV with its relaxed rules on condition bits to VSELECT which has strict rules about all bits of the condition element being the same. Its more correct to go from VSELECT to BLENDV.

Differential Revision: https://reviews.llvm.org/D56771

llvm-svn: 351380
2019-01-16 21:46:28 +00:00
Craig Topper e5b7cc8aa0 [X86] Add a one use check to the setcc inversion code in combineVSelectWithAllOnesOrZeros
If we're going to generate a new inverted setcc, we should make sure we will be able to remove the old setcc.

Differential Revision: https://reviews.llvm.org/D56765

llvm-svn: 351378
2019-01-16 21:29:29 +00:00
Andrea Di Biagio c5f0f5309e [X86][BtVer2] Update latency of horizontal operations.
On Jaguar, horizontal adds/subs have local forwarding disable.
That means, we pay a compulsory extra cycle of write-back stage, and the value
is not available until the end of that stage.

This patch changes the latency of horizontal operations by adding an extra
cycle. With this patch, latency numbers now match what is reported by perf.

I plan to send another patch to also 'fix' the latency of shuffle operations (on
Jaguar, local forwarding is disabled for vector shuffles too).

Differential Revision: https://reviews.llvm.org/D56777

llvm-svn: 351366
2019-01-16 18:18:01 +00:00
Simon Pilgrim 5a2bbe267a [X86] getFauxShuffleMask - bail for non-byte aligned shuffle types
Remove the existing assertion and just return false for unexpected shuffle value types (<X x i1> mainly....).

Found while updating combineX86ShufflesRecursively to run within SimplifyDemandedVectorElts/SimplifyDemandedBits.

llvm-svn: 351365
2019-01-16 18:15:31 +00:00
Simon Pilgrim 524daea429 [X86] Add combineX86ShufflesRecursively helper. NFCI.
combineX86ShufflesRecursively is pretty cumbersome with a lot of arguments that only matter later in recursion.

This commit adds a wrapper version that only takes the initial root Op to simplify calls that don't need to worry about these.

An early, cleanup step towards merging combineX86ShufflesRecursively into SimplifyDemandedVectorElts/SimplifyDemandedBits.

llvm-svn: 351352
2019-01-16 16:01:42 +00:00
Sanjay Patel 0dbecd05ed [x86] lower shuffle of extracts to AVX2 vperm instructions
I was trying to prevent shuffle regressions while matching more horizontal ops 
and ended up here:
  shuf (extract X, 0), (extract X, 4), Mask --> extract (shuf X, undef, Mask'), 0

The affected tests were added for:
https://bugs.llvm.org/show_bug.cgi?id=34380

This patch won't change the examples in the bug report itself, but we should be 
able to extend this to catch more types.

Differential Revision: https://reviews.llvm.org/D56756

llvm-svn: 351346
2019-01-16 14:15:18 +00:00
Mandeep Singh Grang 436735c3fe [EH] Rename llvm.x86.seh.recoverfp intrinsic to llvm.eh.recoverfp
Summary:
Make recoverfp intrinsic target-independent so that it can be implemented for AArch64, etc.
Refer D53541 for the context. Clang counterpart D56748.

Reviewers: rnk, efriedma

Reviewed By: rnk, efriedma

Subscribers: javed.absar, kristof.beyls, llvm-commits

Differential Revision: https://reviews.llvm.org/D56747

llvm-svn: 351281
2019-01-16 00:37:13 +00:00
Craig Topper 0e420e6a62 [X86] Rename SHRUNKBLEND ISD node to BLENDV.
That's really what it is. If we didn't use intrinsics for BLENDVPS/BLENDVPD/PBLENDVB all the way to isel, this is the node we would use.

llvm-svn: 351278
2019-01-16 00:20:30 +00:00
Craig Topper 34ac509ac8 [X86] Add avx512 scatter intrinsics that use a vXi1 mask instead of a scalar integer.
We're trying to have the vXi1 types in IR as much as possible. This prevents the need for bitcasts when the producer of the mask was already a vXi1 value like an icmp. The bitcasts can be subject to code motion and interfere with basic block at a time isel in bad ways.

llvm-svn: 351275
2019-01-15 23:36:25 +00:00