Commit Graph

9448 Commits

Author SHA1 Message Date
Craig Topper
8d64abddd1 [DAGCombiner] Remove an unused argument from tryFoldToZero. NFC
llvm-svn: 346118
2018-11-05 05:53:03 +00:00
Craig Topper
3292ea03d3 [DAGCombiner] Remove 'else' after return. NFC
This makes this code consistent with the nearly identical code in visitZERO_EXTEND.

llvm-svn: 346090
2018-11-04 06:56:32 +00:00
Craig Topper
1ba86188cf [SelectionDAG] Remove special methods for creating *_EXTEND_VECTOR_INREG nodes. Move asserts into getNode.
These methods were just wrappers around getNode with additional asserts (identical and repeated 3 times). But getNode already has a switch that can be used to hold these asserts that allows them to be shared for all 3 opcodes. This also enables checking on the places that create these nodes without using the wrappers.

The rest of the patch is just changing all callers to use getNode directly.

llvm-svn: 346087
2018-11-04 02:10:18 +00:00
Craig Topper
60c202a494 [X86] Don't emit *_extend_vector_inreg nodes when both the input and output types are legal with AVX1
We already have custom lowering for the AVX case in LegalizeVectorOps. So its better to keep the regular extend op around as long as possible.

I had to qualify one place in DAG combine that created illegal vector extending load operations. This change by itself had no effect on any tests which is why its included here.

I've made a few cleanups to the custom lowering. The sign extend code no longer creates an identity shuffle with undef elements. The zero extend code now emits a zero_extend_vector_inreg instead of an unpckl with a zero vector.

For the high half of the custom lowering of zero_extend/any_extend, we're now using an unpckh with a zero vector or undef. Previously we used used a pshufd to move the upper 64-bits to the lower 64-bits and then used a zero_extend_vector_inreg. I think the zero vector should require less execution resources and be smaller code size.

Differential Revision: https://reviews.llvm.org/D54024

llvm-svn: 346043
2018-11-02 21:09:49 +00:00
Simon Pilgrim
cdcbeb4997 [DAGCombiner] Remove reduceBuildVecConvertToConvertBuildVec and rely on the vectorizers instead (PR35732)
reduceBuildVecConvertToConvertBuildVec vectorizes int2float in the DAGCombiner, which means that even if the LV/SLP has decided to keep scalar code using the cost models, this will override this.

While there are cases where vectorization is necessary in the DAG (mainly due to legalization artefacts), I don't think this is the case here, we should assume that the vectorizers know what they are doing.

Differential Revision: https://reviews.llvm.org/D53712

llvm-svn: 345964
2018-11-02 11:06:18 +00:00
Mandeep Singh Grang
547a0d765a [COFF, ARM64] Implement Intrinsic.sponentry for AArch64
Summary: This patch adds Intrinsic.sponentry. This intrinsic is required to correctly support setjmp for AArch64 Windows platform.

Patch by: Yin Ma (yinma@codeaurora.org)

Reviewers: mgrang, ssijaric, eli.friedman, TomTan, mstorsjo, rnk, compnerd, efriedma

Reviewed By: efriedma

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

Differential Revision: https://reviews.llvm.org/D53996

llvm-svn: 345909
2018-11-01 23:22:25 +00:00
Craig Topper
e2483020f2 [DAGCombiner] Make the isTruncateOf call from visitZERO_EXTEND work for vectors. Remove FIXME.
I'm having trouble creating a test case for the ISD::TRUNCATE part of this that shows any codegen differences. But I was able to test the setcc path which is what the test changes here cover.

llvm-svn: 345908
2018-11-01 23:21:45 +00:00
Simon Pilgrim
b34a052852 [LegalizeDAG] Add generic vector CTPOP expansion (PR32655)
This patch adds support for expanding vector CTPOP instructions and removes the x86 'bitmath' lowering which replicates the same expansion.

Differential Revision: https://reviews.llvm.org/D53258

llvm-svn: 345869
2018-11-01 18:22:11 +00:00
Mandeep Singh Grang
b0cdf56dd7 Revert "[COFF, ARM64] Implement Intrinsic.sponentry for AArch64"
This reverts commit 585b6667b4712e3c7f32401e929855b3313b4ff2.

llvm-svn: 345863
2018-11-01 17:53:57 +00:00
Sanjay Patel
c5fe3ce2ec [DAGCombiner] make sure we have a whole-number extract before trying to narrow a vector op (PR39511)
The test causes a crash because we were trying to extract v4f32 to v3f32, and the
narrowing factor was then 4/3 = 1 producing a bogus narrow type.

This should fix:
https://bugs.llvm.org/show_bug.cgi?id=39511

llvm-svn: 345842
2018-11-01 15:41:12 +00:00
Mandeep Singh Grang
88ad9ac720 [COFF, ARM64] Implement Intrinsic.sponentry for AArch64
Summary: This patch adds Intrinsic.sponentry. This intrinsic is required to correctly support setjmp for AArch64 Windows platform.

Reviewers: mgrang, TomTan, rnk, compnerd, mstorsjo, efriedma

Reviewed By: efriedma

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

Differential Revision: https://reviews.llvm.org/D53673

llvm-svn: 345791
2018-10-31 23:16:20 +00:00
Stanislav Mekhanoshin
222e9c11f7 Check shouldReduceLoadWidth from SimplifySetCC
SimplifySetCC could shrink a load without checking for
profitability or legality of such shink with a target.

Added checks to prevent shrinking of aligned scalar loads
in AMDGPU below dword as scalar engine does not support it.

Differential Revision: https://reviews.llvm.org/D53846

llvm-svn: 345778
2018-10-31 21:24:30 +00:00
Scott Linder
92bb783cfe [SelectionDAG] Handle constant range [0,1) in lowerRangeToAssertZExt
lowerRangeToAssertZExt currently relies on something like EarlyCSE having
eliminated the constant range [0,1). At -O0 this leads to an assert.

Differential Revision: https://reviews.llvm.org/D53888

llvm-svn: 345770
2018-10-31 19:57:36 +00:00
Craig Topper
eeac12af6d [SelectionDAGISel] Suppress a -Wunused-but-set-variable warning in release builds. NFC
llvm-svn: 345761
2018-10-31 18:46:15 +00:00
Simon Pilgrim
077a9adb00 Fix comment typo. NFCI.
llvm-svn: 345758
2018-10-31 18:19:52 +00:00
Simon Pilgrim
805cdcfe73 [SelectionDAG] SelectionDAGLegalize::ExpandBITREVERSE - ensure we use ShiftTy
We should be using the getShiftAmountTy value type for shift amounts.

llvm-svn: 345756
2018-10-31 18:14:14 +00:00
David Bolvansky
d0080c3a5f [DAGCombiner] Fold 0 div/rem X to 0
Reviewers: RKSimon, spatel, javed.absar, craig.topper, t.p.northover

Reviewed By: RKSimon

Subscribers: craig.topper, llvm-commits

Differential Revision: https://reviews.llvm.org/D52504

llvm-svn: 345721
2018-10-31 14:18:57 +00:00
Cameron McInally
2ad870e785 [FPEnv] [FPEnv] Add constrained intrinsics for MAXNUM and MINNUM
Differential Revision: https://reviews.llvm.org/D53216

llvm-svn: 345650
2018-10-30 21:01:29 +00:00
Bjorn Pettersson
fe09a20f09 [DAGCombiner] Fix for big endian in ForwardStoreValueToDirectLoad
Summary:
Normalize the offset for endianess before checking
if the store cover the load in ForwardStoreValueToDirectLoad.

Without this we missed out on some optimizations for big
endian targets. If for example having a 4 bytes store followed
by a 1 byte load, loading the least significant byte from the
store, the STCoversLD check would fail (see @test4 in
test/CodeGen/AArch64/load-store-forwarding.ll).

This patch also fixes a problem seen in an out-of-tree target.
The target has i40 as a legal type, it is big endian,
and the StoreSize for i40 is 48 bits. So when normalizing
the offset for endianess we need to take the StoreSize into
account (assuming that padding added when storing into
a larger StoreSize always is added at the most significant
end).

Reviewers: niravd

Reviewed By: niravd

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

Differential Revision: https://reviews.llvm.org/D53776

llvm-svn: 345636
2018-10-30 20:16:39 +00:00
Nirav Dave
eedd2ccd02 [DAG] Add const variants for BaseIndexOffset functions.
llvm-svn: 345623
2018-10-30 18:26:43 +00:00
Sanjay Patel
8b207defea [DAGCombiner] narrow vector binops when extraction is cheap
Narrowing vector binops came up in the demanded bits discussion in D52912.

I don't think we're going to be able to do this transform in IR as a canonicalization 
because of the risk of creating unsupported widths for vector ops, but we already have 
a DAG TLI hook to allow what I was hoping for: isExtractSubvectorCheap(). This is 
currently enabled for x86, ARM, and AArch64 (although only x86 has existing regression 
test diffs).

This is artificially limited to not look through bitcasts because there are so many 
test diffs already, but that's marked with a TODO and is a small follow-up.

Differential Revision: https://reviews.llvm.org/D53784

llvm-svn: 345602
2018-10-30 14:14:34 +00:00
Sanjay Patel
680c9227ca [SelectionDAG] fix build warning for mismatched signs in compare; NFC
llvm-svn: 345598
2018-10-30 13:47:19 +00:00
Simon Pilgrim
858303b827 [SelectionDAG] Add FoldBUILD_VECTOR to simplify new BUILD_VECTOR nodes
Similar to FoldCONCAT_VECTORS, this patch adds FoldBUILD_VECTOR to simplify cases that can avoid the creation of the BUILD_VECTOR - if all the operands are UNDEF or if the BUILD_VECTOR simplifies to a copy.

This exposed an assumption in some AMDGPU code that getBuildVector was guaranteed to be a BUILD_VECTOR node that I've tried to handle.	
	
Differential Revision: https://reviews.llvm.org/D53760

llvm-svn: 345578
2018-10-30 10:32:11 +00:00
David Bolvansky
dfdbb038e8 [DAGCombiner] Improve X div/rem Y fold if single bit element type
Summary: Tests by @spatel, thanks

Reviewers: spatel, RKSimon

Reviewed By: spatel

Subscribers: sdardis, atanasyan, llvm-commits, spatel

Differential Revision: https://reviews.llvm.org/D52668

llvm-svn: 345575
2018-10-30 09:07:22 +00:00
Craig Topper
b293322cee [LegalizeTypes] Teach PromoteIntRes_BITCAST to better handle a bitcast with vector output type and a vector input type that needs to be widened
Summary: Previously if we had a bitcast vector output type that needs promotion and a vector input type that needs widening we would just do a stack store and load to handle the conversion. We can do a little better if we can widen the bitcast to a legal vector type the same size as the widened input type. Then we can do the bitcast between this widened type and the widened input type. Afterwards we can extract_subvector back to the original output and any_extend that. Type legalization will then circle back and handle promotion of the extract_subvector and the any_extend will just be removed. This will avoid going through the stack and allows us to remove a custom version of this legalization from X86.

Reviewers: efriedma, RKSimon

Reviewed By: efriedma

Subscribers: javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D53229

llvm-svn: 345567
2018-10-30 03:27:15 +00:00
Leonard Chan
905abe5b5d [Intrinsic] Signed and Unsigned Saturation Subtraction Intirnsics
Add an intrinsic that takes 2 integers and perform saturation subtraction on
them.

This is a part of implementing fixed point arithmetic in clang where some of
the more complex operations will be implemented as intrinsics.

Differential Revision: https://reviews.llvm.org/D53783

llvm-svn: 345512
2018-10-29 16:54:37 +00:00
Craig Topper
7a18b4bc51 [SelectionDAG] Fix bad indentation. NFC
llvm-svn: 345481
2018-10-28 21:24:20 +00:00
Simon Pilgrim
3497d536f7 [TargetLowering] Move i64/vXi64 to f32/vXf32 UINT_TO_FP handling to TargetLowering::expandUINT_TO_FP.
llvm-svn: 345478
2018-10-28 15:34:35 +00:00
Simon Pilgrim
9b77f0c291 [VectorLegalizer] Enable TargetLowering::expandFP_TO_UINT support.
Add vector support to TargetLowering::expandFP_TO_UINT.

This exposes an issue in X86TargetLowering::LowerVSELECT which was assuming that the select mask was the same width as the LHS/RHS ops - as long as the result is a sign splat we can easily sext/trunk this.

llvm-svn: 345473
2018-10-28 13:07:25 +00:00
Craig Topper
c4b785ae1e [DAGCombiner] Better constant vector support for FCOPYSIGN.
Enable constant folding when both operands are vectors of constants.

Turn into FNEG/FABS when the RHS is a splat constant vector.

llvm-svn: 345469
2018-10-28 01:32:49 +00:00
Simon Pilgrim
3cf33fcdd6 [TargetLowering] Move LegalizeDAG FP_TO_UINT handling to TargetLowering::expandFP_TO_UINT. NFCI.
First step towards fixing PR17686 and adding vector support.

llvm-svn: 345452
2018-10-27 12:15:58 +00:00
Sanjay Patel
0eddd4730f [DAGCombiner] rearrange code in narrowExtractedVectorBinOp(); NFC
We can extend this code to handle many more cases 
if an extract is cheap, so prepping for that change.

llvm-svn: 345430
2018-10-26 21:32:04 +00:00
Craig Topper
7bf85f5c8d [LegalizeTypes] Stop DAGTypeLegalizer::getSETCCWidenedResultTy from creating illegal setccs. Add checks for valid setccs
The DAGTypeLegalizer::getSETCCWidenedResultTy was widening the MaskVT, but the code in convertMask called after getSETCCWidenedResultTy had no idea this widening had occurred. So none of the operands were widened when convertMask created new setccs with the widened VT.

This patch removes the widening and adds some asserts to getNode to validate the types of setccs to prevent issues like this in the future.

Differential Revision: https://reviews.llvm.org/D53743

llvm-svn: 345428
2018-10-26 20:59:55 +00:00
Eli Friedman
2ac1162917 [ARM] Make InstrEmitter mark CPSR defs dead for Thumb1.
The "dead" markings allow existing target-independent optimizations,
like MachineSink, to trigger more frequently. The CPSR defs would have
eventually been marked dead by LiveVariables, so this only affects
optimizations before regalloc.

The ARMBaseInstrInfo.cpp change is fixing a bug which is only visible
with this change: the transform adds a use to an otherwise dead def
of CPSR. This is covered by existing regression tests.

thumb2-tbh.ll breaks for Thumb1 due to MachineLICM changing the
generated code; I'll fix it in D53452.

Differential Revision: https://reviews.llvm.org/D53453

llvm-svn: 345420
2018-10-26 19:32:24 +00:00
Heejin Ahn
24faf859e5 Reland "[WebAssembly] LSDA info generation"
Summary:
This adds support for LSDA (exception table) generation for wasm EH.
Wasm EH mostly follows the structure of Itanium-style exception tables,
with one exception: a call site table entry in wasm EH corresponds to
not a call site but a landing pad.

In wasm EH, the VM is responsible for stack unwinding. After an
exception occurs and the stack is unwound, the control flow is
transferred to wasm 'catch' instruction by the VM, after which the
personality function is called from the compiler-generated code. (Refer
to WasmEHPrepare pass for more information on this part.)

This patch:
- Changes wasm.landingpad.index intrinsic to take a token argument, to
make this 1:1 match with a catchpad instruction
- Stores landingpad index info and catch type info MachineFunction in
before instruction selection
- Lowers wasm.lsda intrinsic to an MCSymbol pointing to the start of an
exception table
- Adds WasmException class with overridden methods for table generation
- Adds support for LSDA section in Wasm object writer

Reviewers: dschuff, sbc100, rnk

Subscribers: mgorny, jgravelle-google, sunfish, llvm-commits

Differential Revision: https://reviews.llvm.org/D52748

llvm-svn: 345345
2018-10-25 23:55:10 +00:00
Cameron McInally
384a74b0e6 [FPEnv] Last BinaryOperator::isFNeg(...) to m_FNeg(...) changes
Replacing BinaryOperator::isFNeg(...) to avoid regressions when we
separate FNeg from the FSub IR instruction.

Differential Revision: https://reviews.llvm.org/D53650

llvm-svn: 345295
2018-10-25 18:09:33 +00:00
Simon Pilgrim
f02c0f8af6 [LegalizeDAG] Remove dead SINT_TO_FP legalization code
As noticed on D52965, the SINT_TO_FP i64 to f32 legalization code has been dead for years - protected by an assert.

Differential Revision: https://reviews.llvm.org/D53703

llvm-svn: 345290
2018-10-25 17:43:36 +00:00
Simon Pilgrim
49d79a864c Missing semicolon.
llvm-svn: 345257
2018-10-25 11:38:17 +00:00
Simon Pilgrim
838eb24014 [TargetLowering] Improve vXi64 UINT_TO_FP vXf64 support (P38226)
As suggested on D52965, this patch moves the i64 to f64 UINT_TO_FP expansion code from LegalizeDAG into TargetLowering and makes it available to LegalizeVectorOps as well.

Not only does this help perform X86 lowering as a true vectorization instead of (partially vectorized) scalar conversions, it avoids the HADDPD op from the scalar code which can be slow on most targets.

The AVX512F does have the vcvtusi2sdq scalar operation but we don't unroll to use it as it seems to only help for the v2f64 case - otherwise the unrolling cost will certainly be too high. My feeling is that we should leave it to the vectorizers - and if it generates the vector UINT_TO_FP we should use it.

Differential Revision: https://reviews.llvm.org/D53649

llvm-svn: 345256
2018-10-25 11:15:57 +00:00
Thomas Lively
30f1d69115 [NFC] Rename minnan and maxnan to minimum and maximum
Summary:
Changes all uses of minnan/maxnan to minimum/maximum
globally. These names emphasize that the semantic difference between
these operations is more than just NaN-propagation.

Reviewers: arsenm, aheejin, dschuff, javed.absar

Subscribers: jholewinski, sdardis, wdng, sbc100, jgravelle-google, jrtc27, atanasyan, llvm-commits

Differential Revision: https://reviews.llvm.org/D53112

llvm-svn: 345218
2018-10-24 22:49:55 +00:00
Thomas Lively
43bc46207a [SelectionDAG] DAG combiner for fminnan and fmaxnan
Summary: Depends on D52765.

Reviewers: aheejin, dschuff

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D52768

llvm-svn: 345210
2018-10-24 22:18:54 +00:00
Tim Northover
05fe8f918b [DAG] check more operands for cycles when merging stores.
Until now, we've only checked whether merging stores would cause a cycle via
the value argument, but the address and indexed offset arguments are also
capable of creating cycles in some situations.

The addresses are all base+offset with notionally the same base, but the base
SDNode may still be different (e.g. via an indexed load in one case, and an
ISD::ADD elsewhere). This allows cycles to creep in if one of these sources
depends on another.

The indexed offset is usually undef (representing a non-indexed store), but on
some architectures (e.g. 32-bit ARM-mode ARM) it can be an arbitrary value,
again allowing dependency cycles to creep in.

llvm-svn: 345200
2018-10-24 21:36:34 +00:00
Simon Pilgrim
6f53b38fd4 [TargetLowering] Add SimplifyDemandedBitsForTargetNode callback
Add a SimplifyDemandedBitsForTargetNode callback to handle target nodes.

Differential Revision: https://reviews.llvm.org/D53643

llvm-svn: 345179
2018-10-24 19:00:56 +00:00
Simon Pilgrim
c8c7451063 [LegalizeDAG] ExpandLegalINT_TO_FP - cleanup UINT_TO_FP i64 -> f32 expansion.
Use SrcVT/DestVT types and correct shift type.

Part of prep work for D52965

llvm-svn: 345158
2018-10-24 16:35:01 +00:00
Matthias Braun
4f82406c46 SelectionDAG: Reuse bigger sized constants in memset expansion.
When implementing memset's today we often see this pattern:
$x0 = MOV 0xXYXYXYXYXYXYXYXY
store $x0, ...
$w1 = MOV 0xXYXYXYXY
store $w1, ...

We first create a 64bit constant in a 64bit register with all bytes the
same and then create a 32bit constant with all bytes the same in a 32bit
register. In many targets we could just access the lower byte of the
64bit register instead.

- Ideally this would be handled by the ConstantHoist pass but it runs
  too early when memset isn't expanded yet.
- The memset expansion code already had this optimization implemented,
  however SelectionDAG constantfolding would constantfold the
  "trunc(bigconstnat)" pattern to "smallconstant".
- This patch makes the memset expansion mark the constant as Opaque and
  stop DAGCombiner from constant folding in this situation. (Similar to
  how ConstantHoisting marks things as Opaque to avoid folding
  ADD/SUB/etc.)

Differential Revision: https://reviews.llvm.org/D53181

llvm-svn: 345102
2018-10-23 23:19:23 +00:00
Simon Pilgrim
8c4796deb4 [LegalizeDAG] Share Vector/Scalar CTPOP Expansion
As suggested on D53258, this patch move the CTPOP expansion code from SelectionDAGLegalize to TargetLowering to allow it to be reused by the VectorLegalizer.

Proper vector support will be added by D53258.

llvm-svn: 345066
2018-10-23 18:28:24 +00:00
Simon Pilgrim
d705ba97dd [LegalizeDAG] Share Vector/Scalar CTLZ Expansion
As suggested on D53258, this patch shares common CTLZ expansion code between VectorLegalizer and SelectionDAGLegalize by putting it in TargetLowering.

Extension to D53474

llvm-svn: 345060
2018-10-23 17:48:30 +00:00
Sanjay Patel
ad12df829c [SelectionDAG] use 'match' to simplify code; NFC
Vector types are not possible here because this code only starts
matching from the scalar bool value of a conditional branch, but
this is another step towards completely removing the fake binop
queries for not/neg/fneg.

llvm-svn: 345041
2018-10-23 15:46:10 +00:00
Benjamin Kramer
1e212e8abb [LegalizeDAG] Remove unused variable
llvm-svn: 345040
2018-10-23 15:43:36 +00:00
Simon Pilgrim
b975ff4700 [LegalizeDAG] Share Vector/Scalar CTTZ Expansion
As suggested on D53258, this patch demonstrates sharing common CTTZ expansion code between VectorLegalizer and SelectionDAGLegalize by putting it in TargetLowering.

I intend to move CTLZ and (scalar) CTPOP over as well and then update D53258 accordingly.

Differential Revision: https://reviews.llvm.org/D53474

llvm-svn: 345039
2018-10-23 15:37:19 +00:00
Leonard Chan
0acfc6be38 [Intrinsic] Unigned Saturation Addition Intrinsic
Add an intrinsic that takes 2 integers and perform unsigned saturation
addition on them.

This is a part of implementing fixed point arithmetic in clang where some of
the more complex operations will be implemented as intrinsics.

Differential Revision: https://reviews.llvm.org/D53340

llvm-svn: 344971
2018-10-22 23:08:40 +00:00
Craig Topper
c8e183f9ee Recommit r344877 "[X86] Stop promoting integer loads to vXi64"
I've included a fix to DAGCombiner::ForwardStoreValueToDirectLoad that I believe will prevent the previous miscompile.

Original commit message:

Theoretically this was done to simplify the amount of isel patterns that were needed. But it also meant a substantial number of our isel patterns have to match an explicit bitcast. By making the vXi32/vXi16/vXi8 types legal for loads, DAG combiner should be able to change the load type to rem

I had to add some additional plain load instruction patterns and a few other special cases, but overall the isel table has reduced in size by ~12000 bytes. So it looks like this promotion was hurting us more than helping.

I still have one crash in vector-trunc.ll that I'm hoping @RKSimon can help with. It seems to relate to using getTargetConstantFromNode on a load that was shrunk due to an extract_subvector combine after the constant pool entry was created. So we end up decoding more mask elements than the lo

I'm hoping this patch will simplify the number of patterns needed to remove the and/or/xor promotion.

Reviewers: RKSimon, spatel

Reviewed By: RKSimon

Subscribers: llvm-commits, RKSimon

Differential Revision: https://reviews.llvm.org/D53306

llvm-svn: 344965
2018-10-22 22:14:05 +00:00
Matt Arsenault
687ec75d10 DAG: Change behavior of fminnum/fmaxnum nodes
Introduce new versions that follow the IEEE semantics
to help with legalization that may need quieted inputs.

There are some regressions from inserting unnecessary
canonicalizes when these are matched from fast math
fcmp + select which should be fixed in a future commit.

llvm-svn: 344914
2018-10-22 16:27:27 +00:00
Sanjay Patel
e439cc2745 [DAGCombiner] reduce insert+bitcast+extract vector ops to truncate (PR39016)
This is a late backend subset of the IR transform added with:
D52439

We can confirm that the conversion to a 'trunc' is correct by running:
$ opt -instcombine -data-layout="e"
(assuming the IR transforms are correct; change "e" to "E" for big-endian)

As discussed in PR39016:
https://bugs.llvm.org/show_bug.cgi?id=39016
...the pattern may emerge during legalization, so that's we are waiting for an 
insertelement to become a scalar_to_vector in the pattern matching here.

The DAG allows for fun variations that are not possible in IR. Result types for 
extracts and scalar_to_vector don't necessarily match input types, so that means 
we have to be a bit more careful in the transform (see code comments).

The tests show that we don't handle cases that require a shift (as we did in the
IR version). I've left that as a potential follow-up because I'm not sure if 
that's a real concern at this late stage.

Differential Revision: https://reviews.llvm.org/D53201

llvm-svn: 344872
2018-10-21 20:13:29 +00:00
Krasimir Georgiev
547d824da6 Revert "[WebAssembly] LSDA info generation"
This reverts commit r344575.
Newly introduced test eh-lsda.ll.test fails with use-after-free under
ASAN build.

llvm-svn: 344639
2018-10-16 18:50:09 +00:00
Leonard Chan
699b3b54da [Intrinsic] Signed Saturation Addition Intrinsic
Add an intrinsic that takes 2 integers and perform saturation addition on them.

This is a part of implementing fixed point arithmetic in clang where some of
the more complex operations will be implemented as intrinsics.

Differential Revision: https://reviews.llvm.org/D53053

llvm-svn: 344629
2018-10-16 17:35:41 +00:00
Simon Pilgrim
ac58636ec5 [LegalizeDAG] ExpandLegalINT_TO_FP - cleanup UINT_TO_FP i64 -> f64 expansion.
Use SrcVT/DestVT types, correct shift type and AND instead of ZERO_EXTEND_IN_REG.

Part of prep work for D52965

llvm-svn: 344602
2018-10-16 10:06:15 +00:00
Heejin Ahn
0981eaab47 [WebAssembly] LSDA info generation
Summary:
This adds support for LSDA (exception table) generation for wasm EH.
Wasm EH mostly follows the structure of Itanium-style exception tables,
with one exception: a call site table entry in wasm EH corresponds to
not a call site but a landing pad.

In wasm EH, the VM is responsible for stack unwinding. After an
exception occurs and the stack is unwound, the control flow is
transferred to wasm 'catch' instruction by the VM, after which the
personality function is called from the compiler-generated code. (Refer
to WasmEHPrepare pass for more information on this part.)

This patch:
- Changes wasm.landingpad.index intrinsic to take a token argument, to
make this 1:1 match with a catchpad instruction
- Stores landingpad index info and catch type info MachineFunction in
before instruction selection
- Lowers wasm.lsda intrinsic to an MCSymbol pointing to the start of an
exception table
- Adds WasmException class with overridden methods for table generation
- Adds support for LSDA section in Wasm object writer

Reviewers: dschuff, sbc100, rnk

Subscribers: mgorny, jgravelle-google, sunfish, llvm-commits

Differential Revision: https://reviews.llvm.org/D52748

llvm-svn: 344575
2018-10-16 00:09:12 +00:00
Sanjay Patel
4cf1da0e02 [SelectionDAG] allow FP binops in SimplifyDemandedVectorElts
This is intended to make the backend on par with functionality that was 
added to the IR version of SimplifyDemandedVectorElts in:
rL343727
...and the original motivation is that we need to improve demanded-vector-elements 
in several ways to avoid problems that would be exposed in D51553.

Differential Revision: https://reviews.llvm.org/D52912

llvm-svn: 344541
2018-10-15 18:05:34 +00:00
Sanjay Patel
8bd74785f0 [DAGCombiner] allow undef elts in vector fmul matching
llvm-svn: 344534
2018-10-15 16:54:07 +00:00
Sanjay Patel
89e2197c33 [DAGCombiner] refactor folds for fadd (fmul X, -2.0), Y; NFCI
The transform doesn't work if the vector constant has undef elements.

llvm-svn: 344532
2018-10-15 16:47:01 +00:00
Sanjay Patel
9e7e0fd828 [DAGCombiner] allow undef elts in vector fma matching
llvm-svn: 344528
2018-10-15 15:56:39 +00:00
Sanjay Patel
4e970ff022 [DAGCombiner] allow undef elts in vector fma matching
llvm-svn: 344525
2018-10-15 15:38:38 +00:00
Chandler Carruth
edb12a838a [TI removal] Make variables declared as TerminatorInst and initialized
by `getTerminator()` calls instead be declared as `Instruction`.

This is the biggest remaining chunk of the usage of `getTerminator()`
that insists on the narrow type and so is an easy batch of updates.
Several files saw more extensive updates where this would cascade to
requiring API updates within the file to use `Instruction` instead of
`TerminatorInst`. All of these were trivial in nature (pervasively using
`Instruction` instead just worked).

llvm-svn: 344502
2018-10-15 10:04:59 +00:00
Simon Pilgrim
a0590a4f7a [LegalizeDAG] Don't bother with final MUL+SRL stage for byte CTPOP.
The final stage of CTPOP expansion (v = (v * 0x01010101...) >> (Len - 8)) is completely pointless for the byte (Len = 8) case as it reduces to (v = (v * 0x01...) >> 0), but annoyingly this doesn't always get optimized away. 

Found while investigating generic vector CTPOP expansion (PR32655).

llvm-svn: 344477
2018-10-14 15:56:28 +00:00
Simon Pilgrim
28a143f738 Pull out repeated variables from SelectionDAGLegalize::ExpandBitCount.
The CTPOP case has been changed from VT.getSizeInBits to VT.getScalarSizeInBits - but this fits in with future work for vector support (PR32655) and doesn't affect any current (scalar) uses.

llvm-svn: 344461
2018-10-13 18:40:48 +00:00
Craig Topper
189e5b4ab6 [LegalizeTypes] Prevent an assertion from PromoteIntRes_BSWAP and PromoteIntRes_BITREVERSE if the shift amount is too large for the VT returned by getShiftAmountTy
Summary:
getShiftAmountTy for X86 returns MVT::i8. If a BSWAP or BITREVERSE is created that requires promotion and the difference between the original VT and the promoted VT is more than 255 then we won't able to create the constant.

This patch adds a check to replace the result from getShiftAmountTy to MVT::i32 if the difference won't fit. This should get legalized later when the shift is ultimately expanded since its clearly an illegal type that we're only promoting to make it a power of 2 bit width. Alternatively we could base the decision completely on the largest shift amount the promoted VT could use.

Vectors should be immune here because getShiftAmountTy always returns the incoming VT for vectors. Only the scalar shift amount can be changed by the targets.

Reviewers: eli.friedman, RKSimon, spatel

Reviewed By: RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D53232

llvm-svn: 344460
2018-10-13 17:47:20 +00:00
Simon Pilgrim
c5d7c6e5f6 [X86][SSE] Remove most of vector CTTZ custom lowering and use LegalizeDAG instead.
There is one remnant - AVX1 custom splitting of 256-bit vectors - which is due to a regression where the X86ISD::ANDNP is still performed as a YMM.

I've also tightened the CTLZ or CTPOP lowering in SelectionDAGLegalize::ExpandBitCount to require a legal CTLZ - it doesn't affect existing users and fixes an issue with AVX512 codegen.

llvm-svn: 344457
2018-10-13 16:11:15 +00:00
Simon Pilgrim
1c2051ead7 [X86][SSE] Begin removing vector CTTZ custom lowering and use LegalizeDAG instead.
Adds CTTZ vector legalization support and begins the removal of the X86/SSE custom lowering. 

llvm-svn: 344453
2018-10-13 15:16:55 +00:00
Thomas Lively
16c349d892 [Intrinsic] Add llvm.minimum and llvm.maximum instrinsic functions
Summary:
These new intrinsics have the semantics of the `minimum` and `maximum`
operations specified by the latest draft of IEEE 754-2018. Unlike
llvm.minnum and llvm.maxnum, these new intrinsics propagate NaNs and
always treat -0.0 as less than 0.0. `minimum` and `maximum` lower
directly to the existing `fminnan` and `fmaxnan` ISel DAG nodes. It is
safe to reuse these DAG nodes because before this patch were only
emitted in situations where there were known to be no NaN arguments or
where NaN propagation was correct and there were known to be no zero
arguments. I know of only four backends that lower fminnan and
fmaxnan: WebAssembly, ARM, AArch64, and SystemZ, and each of these
lowers fminnan and fmaxnan to instructions that are compatible with
the IEEE 754-2018 semantics.

Reviewers: aheejin, dschuff, sunfish, javed.absar

Subscribers: kristof.beyls, dexonsmith, kristina, llvm-commits

Differential Revision: https://reviews.llvm.org/D52764

llvm-svn: 344437
2018-10-13 07:21:44 +00:00
Craig Topper
a796580903 [LegalizeVectorTypes] Use TLI.getVectorIdxTy instead of DAG.getIntPtrConstant.
There's no guarantee that vector indices should use pointer types. So use the correct query method.

llvm-svn: 344428
2018-10-12 22:55:17 +00:00
Craig Topper
435e38a5df [LegalizeVectorTypes] When widening the result of a bitcast from a scalar type, use a scalar_to_vector to turn the scalar into a vector intead of a build vector full of mostly undefs.
This is more consistent with what we usually do and matches some code X86 custom emits in some cases that I think I can cleanup.

The MIPS test change just looks to be an instruction ordering change.

llvm-svn: 344422
2018-10-12 21:59:55 +00:00
Craig Topper
1bb0c6041a [LegalizeVectorTypes] When widening the operands to a concat_vectors, see if we can use the widened operand 0 if the width matches and the other operands are undef.
This saves a conversion to extracts and build_vector. We already do this when both the result and the input need to be widened to the same type.

This changed the sse-intrinsics-fast-isel test because we don't lower (insert_vector_elt (scalar_to_vector X), Y, 1) well. We turn it into (vector_shuffle (scalar_to_vector X), (scalar_to_vector Y), <0, 4, 2, 3>) losing track of the fact that the upper elts could be undef.

We should probably find a way to prevent the scalarization of the <2 x f32> load on these tests.

llvm-svn: 344404
2018-10-12 19:37:49 +00:00
Craig Topper
05f014a684 [LegalizeVectorTypes] When unrolling in WidenVecRes_Convert, make sure we use the original vector element count. Not min of the widened result type and the possibly widened input type.
If the input type is widened as well, but we still were forced to unroll, we shouldn't be considering the widened input element count. We should only create as many scalar operations as the original type called for.

This will be important for an upcoming patch.

llvm-svn: 344403
2018-10-12 19:37:47 +00:00
Simon Pilgrim
c046b6856e Pull out repeated value types. NFCI.
llvm-svn: 344355
2018-10-12 15:49:19 +00:00
Simon Pilgrim
b926fd7b36 Pull out repeated value types. NFCI.
llvm-svn: 344354
2018-10-12 15:48:47 +00:00
Simon Pilgrim
b8339c0167 [SelectionDAG] Move VectorLegalizer::ExpandCTLZ codegen into SelectionDAGLegalize
Generalize SelectionDAGLegalize's CTLZ expansion to handle vectors - lets VectorLegalizer::ExpandCTLZ to just pass the expansion on instead of repeating the same codegen.

llvm-svn: 344349
2018-10-12 14:45:57 +00:00
Sanjay Patel
56b6660d2e [DAGCombiner] rearrange extract_element+bitcast fold; NFC
I want to add another pattern here that includes scalar_to_vector,
so this makes that patch smaller. I was hoping to remove the
hasOneUse() check because it shouldn't be necessary for common
codegen, but an AMDGPU test has a comment suggesting that the
extra check makes things better on one of those targets.

llvm-svn: 344320
2018-10-11 23:56:56 +00:00
Nirav Dave
f1f2a2a31a [DAG] Fix Big Endian in Load-Store forwarding
Summary:
Correct offset calculation in load-store forwarding for big-endian
targets.

Reviewers: rnk, RKSimon, waltl

Subscribers: sdardis, nemanjai, hiraditya, jrtc27, atanasyan, jsji, llvm-commits

Differential Revision: https://reviews.llvm.org/D53147

llvm-svn: 344272
2018-10-11 18:28:59 +00:00
Sanjay Patel
4875662e57 [DAGCombiner] move comment closer to the corresponding code; NFC
llvm-svn: 344255
2018-10-11 16:07:25 +00:00
Nirav Dave
07acc992dc [DAGCombine] Improve Load-Store Forwarding
Summary:
Extend analysis forwarding loads from preceeding stores to work with
extended loads and truncated stores to the same address so long as the
load is fully subsumed by the store.

Hexagon's swp-epilog-phis.ll and swp-memrefs-epilog1.ll test are
deleted as they've no longer seem to be relevant.

Reviewers: RKSimon, rnk, kparzysz, javed.absar

Subscribers: sdardis, nemanjai, hiraditya, atanasyan, llvm-commits

Differential Revision: https://reviews.llvm.org/D49200

llvm-svn: 344142
2018-10-10 14:15:52 +00:00
Simon Pilgrim
bc7b6251b6 [TargetLowering] SimplifyDemandedBits - rename demanded mask args. NFCI.
Help stop bugs like rL343935 by making the 'original' DemandedBits arg more obviously not the mask that is actually used.

llvm-svn: 344138
2018-10-10 13:00:49 +00:00
Simon Pilgrim
53a503f6ac [TargetLowering] SimplifyDemandedBits - pull out repeated getOperands. NFCI.
Part of a minor cleanup to make all the switch statements more consistent prior to improving vector support.

llvm-svn: 344136
2018-10-10 12:32:13 +00:00
Simon Pilgrim
5cb3a82892 [TargetLowering] Add root node back to work list after successful SimplifyDemandedBits/SimplifyDemandedVectorElts
Similar to what already happens in the DAGCombiner wrappers, this patch adds the root nodes back onto the worklist if the DCI wrappers' SimplifyDemandedBits/SimplifyDemandedVectorElts were successful.

Differential Revision: https://reviews.llvm.org/D53026

llvm-svn: 344132
2018-10-10 10:44:15 +00:00
Nemanja Ivanovic
72d4866e57 [DAGCombiner] Expand combining of FP logical ops to sign-setting FP ops
We already do the following combines:
(bitcast int (and (bitcast fp X to int), 0x7fff...) to fp) -> fabs X
(bitcast int (xor (bitcast fp X to int), 0x8000...) to fp) -> fneg X

When the target has "bit preserving fp logic". This patch just extends it
to also combine:
(bitcast int (or (bitcast fp X to int), 0x8000...) to fp) -> fneg (fabs X)

As some targets have fnabs and even those that don't can efficiently lower
both the fabs and the fneg.

Differential revision: https://reviews.llvm.org/D44548

llvm-svn: 344093
2018-10-09 23:20:11 +00:00
Simon Pilgrim
23f880317a [SelectionDAG] Add SIGN_EXTEND_VECTOR_INREG and CONCAT_VECTORS support to SimplifyDemandedBits
Fix for AVX1 masked load/store regression on D52964

llvm-svn: 344043
2018-10-09 13:13:35 +00:00
Sanjay Patel
b64c0d7b53 [DAGCombiner] simplify code for fmul with constant fold; NFCI
llvm-svn: 343997
2018-10-08 21:17:20 +00:00
Alex Bradbury
f27c67af12 [SelectionDAGBuilder][NFC] Pass LHSTy to getShiftAmountTy rather than RHSTy
r126518 introduced a a type parameter to the getShiftAmountTy target hook. It 
produces the type of the shift (RHSTy), parameterised by the type of the value 
being shifted (LHSTy). SelectionDAGBuilder::visitShift passed RHSTy rather 
than LHSTy and this patch corrects this. The change is a no-op because in LLVM 
IR the LHS and RHS types for a shift must be equal anyway.

llvm-svn: 343955
2018-10-08 06:24:59 +00:00
Craig Topper
98dd9d6896 Revert r343948 "[LegalizeDAG] Make one of the ReplaceNode signatures take an ArrayRef instead a pointer to an array. Add assert on size of array. NFC"
The assert is failing some asan tests on the bots.

llvm-svn: 343950
2018-10-08 03:12:12 +00:00
Craig Topper
c058a68784 [LegalizeDAG] Make one of the ReplaceNode signatures take an ArrayRef instead a pointer to an array. Add assert on size of array. NFC
llvm-svn: 343948
2018-10-08 02:02:08 +00:00
Craig Topper
cd38de8b15 [LegalizeDAG] Move legalization of scatter and masked store from LegalizeVectorOps to LegalizeDAG.
This is where we legalize gather and masked load so this is consistent.

Since these ops are always on vectors I've chosen to go with LegalizeDAG since that's what we do for other vector only ops like BUILD_VECTOR, VECTOR_SHUFFLE, etc. The ScalarizeMaskedMemIntrinsic pass should take care of scalarizing these before SelectionDAG so hopefully we don't need to worry about illegally typed scalar ops being emitted in the legalizing. If we did we would need to do this in LegalizeVectorOps so we could get the second type legalization that runs between LegalizeVectorOps and LegalizeDAG.

llvm-svn: 343947
2018-10-08 00:04:55 +00:00
Sanjay Patel
ecc8af61e7 [DAGCombiner] allow undef elts in vector fadd matching
llvm-svn: 343945
2018-10-07 16:30:42 +00:00
Sanjay Patel
ef76e27985 [DAGCombiner] allow undefs when matching vector splats for fmul folds
llvm-svn: 343942
2018-10-07 16:05:37 +00:00
Sanjay Patel
0b74c840dd [DAGCombiner] allow undef elts in vector fabs/fneg matching
This change is proposed as a part of D44548, but we
need this independently to avoid regressions from improved
undef propagation in SimplifyDemandedVectorElts().

llvm-svn: 343940
2018-10-07 15:32:06 +00:00
Sanjay Patel
46a9dc2e3e [DAGCombiner] shorten code for bitcast+fabs fold; NFC
llvm-svn: 343939
2018-10-07 15:18:30 +00:00
Simon Pilgrim
3b04a4e322 [SelectionDAG] Respect multiple uses in SimplifyDemandedBits to SimplifyDemandedVectorElts simplification
rL343913 was using SimplifyDemandedBits's original demanded mask instead of the adjusted 'NewMask' that accounts for multiple uses of the op (those variable names really need improving....).

Annoyingly many of the test changes (back to pre-rL343913 state) are actually safe - but only because their multiple uses are all by PMULDQ/PMULUDQ.

Thanks to Jan Vesely (@jvesely) for bisecting the bug.

llvm-svn: 343935
2018-10-07 11:45:46 +00:00
Craig Topper
e4d199e360 [LegalizeVectorOps] Make ExpandStrictFPOp return the result corresponding to the result number of the SDValue passed in.
It was always returning the chain which seems to be the result number of the SDValue in the lit tests we have. But I don't know if that's guaranteed.

llvm-svn: 343933
2018-10-07 07:16:44 +00:00
Simon Pilgrim
9c9c97bcf4 [SelectionDAG] Add SimplifyDemandedBits to SimplifyDemandedVectorElts simplification
This patch enables SimplifyDemandedBits to call SimplifyDemandedVectorElts in cases where the demanded bits mask covers entire elements of a bitcasted source vector.

There are a couple of cases here where simplification at a deeper level (such as through bitcasts) prevents further simplification - CommitTargetLoweringOpt only adds immediate uses/users back to the worklist when we might want to combine the original caller again to see what else it can simplify.

As well as that I had to disable handling of bool vector until SimplifyDemandedVectorElts better supports some of their opcodes (SETCC, shifts etc.).

Fixes PR39178

Differential Revision: https://reviews.llvm.org/D52935

llvm-svn: 343913
2018-10-06 10:20:04 +00:00
Sanjay Patel
f6a160a102 [SelectionDAG] allow undefs when matching splat constants
And use that to transform fsub with zero constant operands.
The integer part isn't used yet, but it is proposed for use in
D44548, so adding both enhancements here makes that 
patch simpler.

llvm-svn: 343865
2018-10-05 17:42:19 +00:00
Craig Topper
7d2155e3f9 [X86][LegalizeVectorOps] Use MERGE_VALUES to return two results from LowerLoad. Remove special case code in LegalizeVectorOps that allowed us to only return one result.
Previously we replaced the chain use ourself and return the data result. LegalizeVectorOps then detected that we'd done this and assumed the chain had already been handled.

This commit instead returns a MERGE_VALUES node with two results joined from nodes. This allows LegalizeVectorOps to do all the replacements for us without any special casing. The MERGE_VALUES will be removed by DAG combine.

llvm-svn: 343817
2018-10-04 21:24:24 +00:00
Craig Topper
08ae6774eb [LegalizeIntegerTypes] Fix typo in comment. NFC
llvm-svn: 343750
2018-10-04 02:40:35 +00:00
Matthias Braun
004fe6bf83 DAGCombiner: StoreMerging: Fix bad index calculating when adjusting mismatching vector types
This fixes a case of bad index calculation when merging mismatching
vector types. This changes the existing code to just use the existing
extract_{subvector|element} and a bitcast (instead of bitcast first and
then newly created extract_xxx) so we don't need to adjust any indices
in the first place.

rdar://44584718

Differential Revision: https://reviews.llvm.org/D52681

llvm-svn: 343493
2018-10-01 16:25:50 +00:00
Simon Pilgrim
818cfc40ff [DAG] Don't perform SINT_TO_FP<->UINT_TO_FP custom conversion after legalization
The SINT_TO_FP<->UINT_TO_FP combines for non-negative integers should only occur for legal ops once LegalOperations = true

No test case to hand, noticed when investigating PR38226 + PR38970

llvm-svn: 343405
2018-09-30 12:46:42 +00:00
David Bolvansky
8e90bad63d [DAGCombiner] [NFC] Improve X div/rem 1 fold
Reviewers: spatel

Reviewed By: spatel

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D52661

llvm-svn: 343349
2018-09-28 18:40:30 +00:00
Fangrui Song
0cac726a00 llvm::sort(C.begin(), C.end(), ...) -> llvm::sort(C, ...)
Summary: The convenience wrapper in STLExtras is available since rL342102.

Reviewers: dblaikie, javed.absar, JDevlieghere, andreadb

Subscribers: MatzeB, sanjoy, arsenm, dschuff, mehdi_amini, sdardis, nemanjai, jvesely, nhaehnle, sbc100, jgravelle-google, eraman, aheejin, kbarton, JDevlieghere, javed.absar, gbedwell, jrtc27, mgrang, atanasyan, steven_wu, george.burgess.iv, dexonsmith, kristina, jsji, llvm-commits

Differential Revision: https://reviews.llvm.org/D52573

llvm-svn: 343163
2018-09-27 02:13:45 +00:00
Simon Pilgrim
b0189289bf [DAG] SelectionDAGLegalize::ExpandLegalINT_TO_FP - use getFPExtendOrRound helper. NFCI.
Handles SrcVT == DstVT as well.

llvm-svn: 343121
2018-09-26 16:24:07 +00:00
Simon Pilgrim
e2437689a8 [DAG] ExpandLegalINT_TO_FP - pull out repeated getValueType() call. NFCI.
llvm-svn: 343101
2018-09-26 12:42:19 +00:00
David Green
353cb3d4e5 [CodeGen] Enable tail calls for functions with NonNull attributes.
Adding NonNull as attributes to returned pointers has the unfortunate side
effect of disabling tail calls. This patch ignores the NonNull attribute when
we decide whether to tail merge, in the same way that we ignore the NoAlias
attribute, as it has no affect on the call sequence.

Differential Revision: https://reviews.llvm.org/D52238

llvm-svn: 343091
2018-09-26 10:46:18 +00:00
Mikael Nilsson
9c8e35174e Run VerifyDAGDiverence in debug only
VerifyDAGDiverence costs compilation time, avoid running it in non-debug
builds.

Differential Revision: https://reviews.llvm.org/D52454

llvm-svn: 343086
2018-09-26 09:25:45 +00:00
Craig Topper
b2a00acb24 [DAGCombiner] Remove unnecessary check for visitSDIVLike/visitUDIVLike returning a UDIVREM or SDIVREM node.
This shouldn't be possible and is a leftover from when we used to recursively call combine here.

llvm-svn: 343049
2018-09-25 23:52:07 +00:00
Heejin Ahn
e41be38efd Unify landing pad information adding routines (NFC)
Summary:
We have `llvm::addLandingPadInfo` and `MachineFunction::addLandingPad`,
both of which add landing pad information to populate `LandingPadInfo`
but are called from different locations, which was confusing. This patch
unifies them with one `MachineFunction::addLandingPad` function, which
now has functionlities of both functions.

Reviewers: rnk

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D52428

llvm-svn: 343018
2018-09-25 19:56:44 +00:00
Sanjay Patel
10c11b867a [x86] avoid 256-bit andnp that requires insert/extract with AVX1 (PR37449)
This is the final (I hope!) problem pattern mentioned in PR37749:
https://bugs.llvm.org/show_bug.cgi?id=37749

We are trying to avoid an AVX1 sinkhole caused by having 256-bit bitwise logic ops but no other 256-bit integer ops. 
We've already solved the simple logic ops, but 'andn' is an x86 special. I looked at alternative solutions like 
extending the generic DAG combine or trying to wait until the ANDNP node is created, but those are bigger patches 
that can over-reach. Ie, splitting to 128-bit does not look like a win in most cases with >1 256-bit op.

The pattern matching is cluttered with bitcasts because of our i64 element canonicalization. For the affected test, 
we have this vector-type-legalized sequence:

        t29: v8i32 = concat_vectors t27, t28
      t30: v4i64 = bitcast t29
        t18: v8i32 = BUILD_VECTOR Constant:i32<-1>, Constant:i32<-1>, ...
      t31: v4i64 = bitcast t18
    t32: v4i64 = xor t30, t31
      t9: v8i32 = BUILD_VECTOR Constant:i32<255>, Constant:i32<255>, ...
    t34: v4i64 = bitcast t9
  t35: v4i64 = and t32, t34
t36: v8i32 = bitcast t35
      t37: v4i32 = extract_subvector t36, Constant:i64<0>
      t38: v4i32 = extract_subvector t36, Constant:i64<4>

Differential Revision: https://reviews.llvm.org/D52318

llvm-svn: 343008
2018-09-25 19:09:34 +00:00
Nirav Dave
a2f514d672 [LegalizeDAG] Prune Predecessor check in ExpandExtractFromVectorThroughStack. NFCI.
llvm-svn: 342985
2018-09-25 15:29:57 +00:00
Nirav Dave
f445a67be4 [DAGCombine] Improve Predecessor check in SimplifySelectOps. NFCI.
Reuse search space bookkeeping across multiple predecessor checks
qdone to avoid redundancy. This should cut search cost by ~4x.

llvm-svn: 342984
2018-09-25 15:29:30 +00:00
Nirav Dave
7373d5e646 [DAGCombine] Share predecessor bookkeeping in CombineToPostIndexedLoadStore. NFCI.
llvm-svn: 342983
2018-09-25 15:29:04 +00:00
Nirav Dave
46ab89a0d0 [DAGCombine] Don't fold dependent loads across SELECT_CC.
DAGCombine will try to fold two loads that feed a SELECT or SELECT_CC
after the select, resulting in a select of an address and a single
load after.

If either of the loads depend on the other, this is not legal as it
could introduce cycles. However, it only checked this if the opcode
was a SELECT, and not for a SELECT_CC.

Unfortunately, the only reproducer I have for this is for our
downstream target. I've tried getting it to trigger on an upstream one
but haven't been successful.

Patch thanks to Bevin Hansson.

llvm-svn: 342980
2018-09-25 14:43:05 +00:00
Sanjay Patel
2c901742ca [DAGCombiner] use UADDO to optimize saturated unsigned add
This is a preliminary step towards solving PR14613:
https://bugs.llvm.org/show_bug.cgi?id=14613

If we have an 'add' instruction that sets flags, we can use that to eliminate an
explicit compare instruction or some other instruction (cmn) that sets flags for 
use in the later select.

As shown in the unchanged tests that use 'icmp ugt %x, %a', we're effectively 
reversing an IR icmp canonicalization that replaces a variable operand with a
constant:
https://rise4fun.com/Alive/V1Q

But we're not using 'uaddo' in those cases via DAG transforms. This happens in 
CGP after D8889 without checking target lowering to see if the op is supported. 
So AArch already shows 'uaddo' codegen for the i8/i16/i32/i64 test variants with 
"using_cmp_sum" in the title. That's the pattern that CGP matches as an unsigned 
saturated add and converts to uaddo without checking target capabilities.

This patch is gated by isOperationLegalOrCustom(ISD::UADDO, VT), so we see only 
see AArch diffs for i32/i64 in the tests with "using_cmp_notval" in the title 
(unlike x86 which sees improvements for all sizes because all sizes are 'custom'). 
But the AArch code (like x86) looks better when translated to 'uaddo' in all cases. 
So someone that is involved with AArch may want to set i8/i16 to 'custom' for UADDO, 
so this patch will fire on those tests.

Another possibility given the existing behavior: we could remove the legal-or-custom 
check altogether because we're assuming that a UADDO sequence is canonical/optimal 
before we ever reach here. But that seems like a bug to me. If the target doesn't 
have an add-with-flags op, then it's not likely that we'll get optimal DAG combining 
using a UADDO node. This is similar justification for why we don't canonicalize IR to 
the overflow math intrinsic sibling (llvm.uadd.with.overflow) for UADDO in the first 
place.

Differential Revision: https://reviews.llvm.org/D51929

llvm-svn: 342886
2018-09-24 14:47:15 +00:00
Hans Wennborg
83d15dfe2d Remove debug printf leftover from r342397
llvm-svn: 342863
2018-09-24 08:18:47 +00:00
Craig Topper
5bef27e808 [DAGCombiner] Remove some dead code from ConstantFoldBITCASTofBUILD_VECTOR
This code handled SCALAR_TO_VECTOR being returned by the recursion, but the code that used to return SCALAR_TO_VECTOR was removed in 2015.

llvm-svn: 342856
2018-09-24 02:03:11 +00:00
Craig Topper
b3b94a8e8b [DAGCombiner] Clarify a comment. NFC
This comment was misleading about why we were restricting to before legalize types. The reason given would only apply to before legalize ops. But there is a before legalize types reason that should also be listed.

llvm-svn: 342851
2018-09-23 21:17:56 +00:00
Craig Topper
bec5967176 [LegalizeTypes] Fix bad indentation. NFC
llvm-svn: 342850
2018-09-23 21:17:55 +00:00
Sanjay Patel
0027946915 [DAGCombiner][x86] extend decompose of integer multiply into shift/add with negation
This is an alternative to https://reviews.llvm.org/D37896. We can't decompose 
multiplies generically without a target hook to tell us when it's profitable.

ARM and AArch64 may be able to remove some existing code that overlaps with
this transform.

This extends D52195 and may resolve PR34474: 
https://bugs.llvm.org/show_bug.cgi?id=34474
(still an open question about transforming legal vector multiplies, but we
could open another bug report for those)

llvm-svn: 342844
2018-09-23 18:41:38 +00:00
Craig Topper
81f67f7afb [DAGCombiner] Simplify some code in visitBITCAST. NFCI
llvm-svn: 342826
2018-09-22 23:12:34 +00:00
Craig Topper
e79a588cac [DAGCombiner] Rewrite r331896 in a different way to address a FIXME. NFCI
llvm-svn: 342809
2018-09-22 18:03:14 +00:00
Sanjay Patel
8a1227ccc8 [SelectionDAG] replace duplicated peekThroughBitcast helper functions; NFCI
x86 had 2 versions of peekThroughBitcast. DAGCombiner had 1. Plus, it had a 1-off implementation for the one-use variant.
Move the x86 versions of the code to SelectionDAG, so we don't have different copies of the code. 
No functional change intended.

I'm putting this next to isBitwiseNot() because I am planning to use it in there. Another option is next to the
helpers in the ISD namespace (eg, ISD::isConstantSplatVector()). But if there's no good reason for those to be 
there, I'd prefer to pull other helpers over to SelectionDAG in follow-up steps.

Differential Revision: https://reviews.llvm.org/D52285

llvm-svn: 342669
2018-09-20 17:34:08 +00:00
Sanjay Patel
fdc0de19cb [SelectionDAG] allow vector types with isBitwiseNot()
The test diff in not-and-simplify.ll is from a use in SimplifyDemandedBits,
and the test diff in add.ll is from a DAGCombiner transform.

llvm-svn: 342594
2018-09-19 21:48:30 +00:00
Michael Berg
894c39f770 Copy utilities updated and added for MI flags
Summary: This patch adds a GlobalIsel copy utility into MI for flags and updates the instruction emitter for the SDAG path.  Some tests show new behavior and I added one for GlobalIsel which mirrors an SDAG test for handling nsw/nuw.

Reviewers: spatel, wristow, arsenm

Reviewed By: arsenm

Subscribers: wdng

Differential Revision: https://reviews.llvm.org/D52006

llvm-svn: 342576
2018-09-19 18:52:08 +00:00
Sanjay Patel
4fd2e2a498 [DAGCombiner][x86] add transform/hook to decompose integer multiply into shift/add
This is an alternative to D37896. I don't see a way to decompose multiplies 
generically without a target hook to tell us when it's profitable. 

ARM and AArch64 may be able to remove some duplicate code that overlaps with 
this transform.

As a first step, we're only getting the most clear wins on the vector examples
requested in PR34474:
https://bugs.llvm.org/show_bug.cgi?id=34474

As noted in the code comment, it's likely that the x86 constraints are tighter
than necessary, but it may not always be a win to replace a pmullw/pmulld.

Differential Revision: https://reviews.llvm.org/D52195

llvm-svn: 342554
2018-09-19 15:57:40 +00:00
Matthias Braun
726e12cf0c ScheduleDAG: Cleanup dumping code; NFC
- Instead of having both `SUnit::dump(ScheduleDAG*)` and
  `ScheduleDAG::dumpNode(ScheduleDAG*)`, just keep the latter around.
- Add `ScheduleDAG::dump()` and avoid code duplication in several
  places. Implement it for different ScheduleDAG variants.
- Add `ScheduleDAG::dumpNodeName()` in favor of the `SUnit::print()`
  functions. They were only ever used for debug dumping and putting the
  function into ScheduleDAG is consistent with the `dumpNode()` change.

llvm-svn: 342520
2018-09-19 00:23:35 +00:00
Amara Emerson
91c2913522 Revert "Revert r342183 "[DAGCombine] Fix crash when store merging created an extract_subvector with invalid index.""
Fixed the assertion failure.

llvm-svn: 342397
2018-09-17 14:40:13 +00:00
Sanjay Patel
3eaf500a6d [DAGCombiner] try to convert pow(x, 1/3) to cbrt(x)
This is a follow-up suggested in D51630 and originally proposed as an IR transform in D49040.

Copying the motivational statement by @evandro from that patch:
"This transformation helps some benchmarks in SPEC CPU2000 and CPU2006, such as 188.ammp, 
447.dealII, 453.povray, and especially 300.twolf, as well as some proprietary benchmarks. 
Otherwise, no regressions on x86-64 or A64."

I'm proposing to add only the minimum support for a DAG node here. Since we don't have an 
LLVM IR intrinsic for cbrt, and there are no other DAG ways to create a FCBRT node yet, I 
don't think we need to worry about DAG builder, legalization, a strict variant, etc. We 
should be able to expand as needed when adding more functionality/transforms. For reference, 
these are transform suggestions currently listed in SimplifyLibCalls.cpp:

//   * cbrt(expN(X))  -> expN(x/3)
//   * cbrt(sqrt(x))  -> pow(x,1/6)
//   * cbrt(cbrt(x))  -> pow(x,1/9)

Also, given that we bail out on long double for now, there should not be any logical 
differences between platforms (unless there's some platform out there that has pow()
but not cbrt()).

Differential Revision: https://reviews.llvm.org/D51753

llvm-svn: 342348
2018-09-16 16:50:26 +00:00
Reid Kleckner
4d1b75c6b7 Revert r342183 "[DAGCombine] Fix crash when store merging created an extract_subvector with invalid index."
Causes 'isVector() && "Invalid vector type!"' assertion when building
Skia in Chrome.

llvm-svn: 342265
2018-09-14 19:39:40 +00:00
Adrian Prantl
16f58d1850 Fix debug info for SelectionDAG legalization of DAG nodes with two results.
This patch fixes the debug info handling for SelectionDAG legalization
of DAG nodes with two results. When an replaced SDNode has more than
one result, transferDbgValues was always copying the SDDbgValue from
the first result and attaching them to all members. In reality
SelectionDAG::ReplaceAllUsesWith() is given an array of SDNodes
(though the type signature doesn't make this obvious (cf. the call
site code in ReplaceNode()).

rdar://problem/44162227

Differential Revision: https://reviews.llvm.org/D52112

llvm-svn: 342264
2018-09-14 19:38:45 +00:00
Adrian Prantl
66945cf6e3 fix noasserts build
llvm-svn: 342247
2018-09-14 17:32:52 +00:00
Adrian Prantl
55b8756b8a SelectionDAG: Add compact SDDbgValue representation to -dag-dump-verbose output
llvm-svn: 342245
2018-09-14 17:08:02 +00:00
Adrian Prantl
86497ad2af fix typos
llvm-svn: 342241
2018-09-14 16:12:14 +00:00
Amara Emerson
ef600cbd86 [DAGCombine] Fix crash when store merging created an extract_subvector with invalid index.
Differential Revision: https://reviews.llvm.org/D51831

llvm-svn: 342183
2018-09-13 21:28:58 +00:00
Matt Arsenault
842cda6312 DAG: Fix expansion of unaligned FP loads and stores
This was trying to scalarizing a scalar FP type,
resulting in an assert.

Fixes unaligned f64 stack stores for AMDGPU.

llvm-svn: 342132
2018-09-13 12:14:23 +00:00
Sanjay Patel
8a478b79dc [DAGCombiner] improve formatting for select+setcc code; NFC
llvm-svn: 342095
2018-09-12 23:03:50 +00:00
Craig Topper
26a3799858 [SelectionDAG] Remove some code from PromoteIntOp_MGATHER that handles UpdateNodeOperands returning an existing node instead of updating.
I suspect this became unecessary when the CSE of mgather was fixed in r338080. It may still be possible to hit this if we widen the element type of a gather outside of type legalization and the promote the mask of a separate gather node so they become the same. But that seems pretty unlikely.

llvm-svn: 342022
2018-09-12 05:25:41 +00:00
Matt Arsenault
57b5966dad DAG: Handle odd vector sizes in calling conv splitting
This already worked if only one register piece was used,
but didn't if a type was split into multiple, unequal
sized pieces.

Fixes not splitting 3i16/v3f16 into two registers for
AMDGPU.

This will also allow fixing the ABI for 16-bit vectors
in a future commit so that it's the same for all subtargets.

llvm-svn: 341801
2018-09-10 11:49:23 +00:00
Sanjay Patel
6ebf218e4c [SelectionDAG] enhance vector demanded elements to look at a vector select condition operand
This is the DAG equivalent of D51433.
If we know we're not using all vector lanes, use that knowledge to potentially simplify a vselect condition.

The reduction/horizontal tests show that we are eliminating AVX1 operations on the upper half of 256-bit 
vectors because we don't need those anyway.
I'm not sure what the pr34592 test is showing. That's run with -O0; is SimplifyDemandedVectorElts supposed 
to be running there?

Differential Revision: https://reviews.llvm.org/D51696

llvm-svn: 341762
2018-09-09 14:13:22 +00:00
Simon Pilgrim
96d6b9c2e2 [DAGCombiner] foldBitcastedFPLogic - Add basic vector support
Add support for bitcasts from float type to an integer type of the same element bitwidth.

There maybe cases where we need to support different widths (e.g. as SSE __m128i is treated as v2i64) - but I haven't seen cases of this in the wild yet.

llvm-svn: 341652
2018-09-07 12:13:45 +00:00
Sanjay Patel
dbf52837fe [DAGCombiner] try to convert pow(x, 0.25) to sqrt(sqrt(x))
This was proposed as an IR transform in D49306, but it was not clearly justifiable as a canonicalization. 
Here, we only do the transform when the target tells us that sqrt can be lowered with inline code.

This is the basic case. Some potential enhancements are in the TODO comments:

1. Generalize the transform for other exponents (allow more than 2 sqrt calcs if that's really cheaper).
2. If we have less fast-math-flags, generate code to avoid -0.0 and/or INF.
3. Allow the transform when optimizing/minimizing size (might require a target hook to get that right).

Note that by default, x86 converts single-precision sqrt calcs into sqrt reciprocal estimate with 
refinement. That codegen is controlled by CPU attributes and can be manually overridden. We have plenty 
of test coverage for that already, so I didn't bother to include extra testing for that here. AArch uses 
its full-precision ops in all cases (not sure if that's the intended behavior or not, but that should 
also be covered by existing tests).

Differential Revision: https://reviews.llvm.org/D51630 

llvm-svn: 341481
2018-09-05 17:01:56 +00:00
Matt Arsenault
a6f32f4015 DAG: Factor out helper function for odd vector sizes
llvm-svn: 341392
2018-09-04 18:47:43 +00:00
Scott Linder
cab029f474 [CodeGen] Fix remaining zext() assertions in SelectionDAG
Fix remaining cases not committed in https://reviews.llvm.org/D49574

Differential Revision: https://reviews.llvm.org/D50659

llvm-svn: 341380
2018-09-04 16:33:34 +00:00
Matt Arsenault
ca25b58957 DAG: Handle extract_vector_elt in isKnownNeverNaN
llvm-svn: 341317
2018-09-03 14:01:03 +00:00
Roman Lebedev
d7a6244475 [DAGCombine] optimizeSetCCOfSignedTruncationCheck(): handle inverted pattern
Summary:
A follow-up for D49266 / rL337166 + D49497 / rL338044.

This is still the same pattern to check for the [lack of]
signed truncation, but in this case the constants and the predicate
are negated.

https://rise4fun.com/Alive/BDV
https://rise4fun.com/Alive/n7Z

Reviewers: spatel, craig.topper, RKSimon, javed.absar, efriedma, dmgreen

Reviewed By: spatel

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D51532

llvm-svn: 341287
2018-09-02 13:56:22 +00:00
Craig Topper
6666861158 [DAGCombiner] Fix bad identation. NFC
llvm-svn: 341103
2018-08-30 19:35:40 +00:00
Nicolai Haehnle
35617ed4cb [NFC] Rename the DivergenceAnalysis to LegacyDivergenceAnalysis
Summary:
This is patch 1 of the new DivergenceAnalysis (https://reviews.llvm.org/D50433).

The purpose of this patch is to free up the name DivergenceAnalysis for the new generic
implementation. The generic implementation class will be shared by specialized
divergence analysis classes.

Patch by: Simon Moll

Reviewed By: nhaehnle

Subscribers: jvesely, jholewinski, arsenm, nhaehnle, mgorny, jfb, llvm-commits

Differential Revision: https://reviews.llvm.org/D50434

Change-Id: Ie8146b11be2c50d5312f30e11c7a3036a15b48cb
llvm-svn: 341071
2018-08-30 14:21:36 +00:00
Matt Arsenault
167601e629 DAG: Don't use ABI copies in some contexts
If an ABI-like value is used in a different block,
the type split used is not necessarily the same as
the call's ABI. The value is used through an intermediate
copy virtual registers from the other block. This
resulted in copies with inconsistent sizes later.

Fixes regressions since r338197 when AMDGPU started
splitting vector types for calls.

llvm-svn: 341018
2018-08-30 05:49:28 +00:00
Simon Pilgrim
b49d5f3b53 [DAGCombiner] Add X / X -> 1 & X % X -> 0 folds
Adds more divrem folds to try and get in sync with InstructionSimplify

Differential Revision: https://reviews.llvm.org/D50636

llvm-svn: 340919
2018-08-29 11:30:16 +00:00
Craig Topper
9f42726cc7 [X86] Support v2i32 gather/scatter indices with -x86-experimental-vector-widening-legalization
Summary: This is split out from D41062 to cover the code in LegalVectorTypes.cpp

Reviewers: RKSimon, spatel, efriedma

Reviewed By: efriedma

Subscribers: sdardis, jvesely, nhaehnle, jrtc27, atanasyan, llvm-commits

Differential Revision: https://reviews.llvm.org/D51337

llvm-svn: 340891
2018-08-29 02:12:49 +00:00
Nirav Dave
11e39fb6fb [DAGCombine] Rework MERGE_VALUES to inline in single pass. NFCI.
Avoid hyperlinear cost of inlining MERGE_VALUE node by constructing
temporary vector and doing a single replacement.

llvm-svn: 340853
2018-08-28 18:13:26 +00:00
Nirav Dave
113f2b9058 [DAG] Avoid recomputing Divergence checks. NFCI.
When making multiple updates to the same SDNode, recompute node
divergence only once after all changes have been made.

llvm-svn: 340852
2018-08-28 18:13:00 +00:00
Nirav Dave
0b8cb46e0b [DAG] Fix updateDivergence calculation
Check correct SDNode when deciding if we should update the divergence
property.

llvm-svn: 340851
2018-08-28 18:12:35 +00:00
Craig Topper
c7506b28c1 [DAGCombiner][AMDGPU][Mips] Fold bitcast with volatile loads if the resulting load is legal for the target.
Summary:
I'm not sure if this patch is correct or if it needs more qualifying somehow. Bitcast shouldn't change the size of the load so it should be ok? We already do something similar for stores. We'll change the type of a volatile store if the resulting store is Legal or Custom. I'm not sure we should be allowing Custom there...

I was playing around with converting X86 atomic loads/stores(except seq_cst) into regular volatile loads and stores during lowering. This would allow some special RMW isel patterns in X86InstrCompiler.td to be removed. But there's some floating point patterns in there that didn't work because we don't fold (f64 (bitconvert (i64 volatile load))) or (f32 (bitconvert (i32 volatile load))).

Reviewers: efriedma, atanasyan, arsenm

Reviewed By: efriedma

Subscribers: jvesely, arsenm, sdardis, kzhuravl, wdng, yaxunl, dstuttard, tpr, t-tye, arichardson, jrtc27, atanasyan, jfb, llvm-commits

Differential Revision: https://reviews.llvm.org/D50491

llvm-svn: 340797
2018-08-28 03:47:20 +00:00
Matt Arsenault
cea7c6969d DAG: Check transformed type for forming fminnum/fmaxnum from vselect
Follow up to r340655 to fix vector types which are split.

llvm-svn: 340766
2018-08-27 18:11:31 +00:00
Sanjay Patel
f645927875 [SelectionDAG] add helper query for binops; NFC
We will also use this in a planned enhancement for vector insertelement.

llvm-svn: 340741
2018-08-27 14:20:15 +00:00
Sanjay Patel
113cac3b15 [SelectionDAG][x86] turn insertelement into undef with variable index into splat
I noticed this along with the patterns in D51125, but when the index is variable, 
we don't convert insertelement into a build_vector.

For x86, that means these get expanded at legalization time into the loading/spilling 
code that we see in the tests. I think it's always better to avoid going to memory on 
these, and we get the optimal 'broadcast' if it's available.

I suspect other targets may want to look at enabling the hook. AArch64 and AMDGPU have 
regression tests that would be affected (although I did not check what would happen in 
those cases). In the most basic cases shown here, AArch64 would probably do much 
better with a splat.

Differential Revision: https://reviews.llvm.org/D51186

llvm-svn: 340705
2018-08-26 18:20:41 +00:00
Chandler Carruth
9ae926b973 [IR] Replace isa<TerminatorInst> with isTerminator().
This is a bit awkward in a handful of places where we didn't even have
an instruction and now we have to see if we can build one. But on the
whole, this seems like a win and at worst a reasonable cost for removing
`TerminatorInst`.

All of this is part of the removal of `TerminatorInst` from the
`Instruction` type hierarchy.

llvm-svn: 340701
2018-08-26 09:51:22 +00:00
Craig Topper
a11a3b3818 [SelectionDAG][X86] Reorder the operands the MaskedStoreSDNode to put the value first.
Summary:
Previously the value being stored is the last operand in SDNode. This causes the type legalizer to visit the mask operand before the value operand. The type legalizer was more complicated because of this since we want the type of the value to drive the decisions.

This patch moves the value to be the first operand so we visit it first during type legalization. It also simplifies the type legalization code accordingly.

X86 is currently the only in tree target that uses this SDNode. Not sure if there are any users out of tree.

Reviewers: RKSimon, delena, hfinkel, eli.friedman

Reviewed By: RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D50402

llvm-svn: 340689
2018-08-25 17:48:17 +00:00
Matt Arsenault
5b9ef39bdd DAG: Allow matching fminnum/fmaxnum from vselect
llvm-svn: 340655
2018-08-24 21:24:18 +00:00
Craig Topper
d8e91c3e8d [DAGCombiner][Mips] Don't combine bitcast+store after LegalOperations when the store is volatile, if the resulting store isn't Legal
Previously we allowed the store to be Custom. But without knowing for sure that the Custom handling won't split the store, we shouldn't convert a volatile store. We also probably shouldn't be creating a store the requires custom handling after LegalizeOps. This could lead to an infinite loop if the custom handling was to insert a bitcast. Though I guess isStoreBitCastBeneficial could be used to block such a loop.

The test changes here are due to the volatile part of this. The stores in the test are all volatile and i32 stores are marked custom, So we are no longer converting them

This is related to D50491 where I was trying to allow some bitcasting of volatile loads

Differential Revision: https://reviews.llvm.org/D50578

llvm-svn: 340626
2018-08-24 17:48:25 +00:00
Justin Bogner
fbbd4366a6 [SDAG] Add versions of computeKnownBits that return a value
Having the KnownBits as an output parameter is kind of awkward to use
and a holdover from when it was two separate APInts. Instead, just
return a KnownBits object.

I'm leaving the existing interface in place for now, since updating
the callers all at once would be thousands of lines of diff.

llvm-svn: 340594
2018-08-24 02:42:24 +00:00
Sanjay Patel
ed1b9695ee [SelectionDAG] unroll unsupported vector FP ops earlier to avoid libcalls on undef elements (PR38527)
This solves the motivating case from:
https://bugs.llvm.org/show_bug.cgi?id=38527

If we are legalizing an FP vector op that maps to 1 of the LLVM intrinsics that mimic libm calls, 
but we're going to end up with scalar libcalls for that vector type anyway, then we should unroll 
the vector op into scalars before widening. This avoids libcalls because we've lost the knowledge 
that some of the scalar elements are undef.

Differential Revision: https://reviews.llvm.org/D50791

llvm-svn: 340469
2018-08-22 22:52:05 +00:00
Eli Friedman
96e3cd85bd [ARM] Lower llvm.ctlz.i32 to a libcall when clz is not available.
The inline sequence is very long (about 70 bytes on Thumb1), so it's
not really a good idea to inline it, especially when optimizing for
size.

Differential Revision: https://reviews.llvm.org/D47917

llvm-svn: 340458
2018-08-22 21:47:14 +00:00
Heejin Ahn
9cd7f88a35 [WebAssembly] Don't make wasm cleanuppads into funclet entries
Summary:
Catchpads and cleanuppads are not funclet entries; they are only EH
scope entries. We already dont't set `isEHFuncletEntry` for catchpads.
This patch does the same thing for cleanuppads.

Reviewers: dschuff

Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits

Differential Revision: https://reviews.llvm.org/D50654

llvm-svn: 340330
2018-08-21 20:04:42 +00:00
Sam Parker
597811e7a7 [DAGCombiner] Reduce load widths of shifted masks
During combining, ReduceLoadWdith is used to combine AND nodes that
mask loads into narrow loads. This patch allows the mask to be a
shifted constant. This results in a narrow load which is then left
shifted to compensate for the new offset.

Differential Revision: https://reviews.llvm.org/D50432

llvm-svn: 340261
2018-08-21 10:26:59 +00:00
Simon Pilgrim
72b324de4d [TargetLowering] Add BuildSDiv support for division by one or negone.
This reduces most of the sdiv stages (the MULHS, shifts etc.) to just zero/identity values and use the numerator scale factor to multiply by +1/-1.

llvm-svn: 340260
2018-08-21 10:20:36 +00:00
Cameron McInally
94b9029be9 [FPEnv] Support constrained FREM intrinsic
Differential Revision: https://reviews.llvm.org/D50975

llvm-svn: 340201
2018-08-20 19:28:56 +00:00
Simon Pilgrim
6ac905926f [TargetLowering] Disable BuildSDiv division by one or negone.
Fuzz tests have detected an issue, currently working on a fix.

llvm-svn: 340195
2018-08-20 18:23:54 +00:00
Simon Pilgrim
1a00042270 [SelectionDAG] Reuse the Op's VT. NFCI.
llvm-svn: 340173
2018-08-20 13:44:03 +00:00
Simon Pilgrim
5b78c9d58d [SelectionDAG] Add partial sign-bit support to ComputeNumSignBits for BITCAST nodes
Only adds support to the existing 'large element' scalar/vector to 'small element' vector bitcasts.

Handle the case where the sign bit extends to only part of the small elements.

llvm-svn: 340169
2018-08-20 13:05:48 +00:00
Simon Pilgrim
5b936ec89e [SelectionDAG] Add basic demanded elements support to ComputeNumSignBits for BITCAST nodes
Only adds support to the existing 'large element' scalar/vector to 'small element' vector bitcasts.

The next step would be to support cases where the large elements aren't all sign bits, and determine the small element equivalent based on the demanded elements.

llvm-svn: 340143
2018-08-19 17:47:50 +00:00
Hsiangkai Wang
68c706ceb7 [DebugInfo] In FastISel, convert llvm.dbg.label to DBG_LABEL MI.
Convert llvm.dbg.label(!label_metadata) to DBG_LABEL !label_metadata.

Differential Revision: https://reviews.llvm.org/D50622

llvm-svn: 340122
2018-08-18 14:55:34 +00:00
Craig Topper
cc5dbbf759 [DAGCombiner] Allow divide by constant optimization on opaque constants.
Summary:
I believe this restores the behavior we had before r339147.

Fixes PR38622.

Reviewers: RKSimon, chandlerc, spatel

Reviewed By: chandlerc

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D50936

llvm-svn: 340120
2018-08-18 05:52:42 +00:00
Matt Arsenault
25e51540e1 DAG: Fix isKnownNeverNaN for basic non-sNaN cases
fadd/fsub/fmul need to worry about infinities as well
as fdiv.

llvm-svn: 340085
2018-08-17 21:19:22 +00:00
Simon Pilgrim
03e57521c0 [DAGCombiner] extractShiftForRotate - fix out of range shift issue
Don't just check for negative shift amounts.

Fixes OSS Fuzz #9935
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=9935

llvm-svn: 340015
2018-08-17 12:25:18 +00:00
Simon Pilgrim
5113b48798 [DAGCombine] Improve (sra (sra x, c1), c2) -> (sra x, (add c1, c2)) folding
Add support for cases where only some c1+c2 results exceed the max bitshift, clamping accordingly.

Differential Revision: https://reviews.llvm.org/D35722

llvm-svn: 340010
2018-08-17 10:52:49 +00:00
Chen Zheng
e2d47dd1bb [MISC]Fix wrong usage of std::equal()
Differential Revision: https://reviews.llvm.org/D49958

llvm-svn: 340000
2018-08-17 07:51:01 +00:00
Craig Topper
883ff69c93 [DAGCombiner] Don't reassociate operations that have the vector reduction flag set.
When nodes are reassociated the vector-reduction flag gets lost.

The test case is here is what would happen if you had a sum of absolute differences loop that started with a non-zero but contant sum and that loop was unrolled. The vectorizer will generate a constant vector for the initial value. And DAGCombiner reassociate tries to move it down the addition tree erasing the vector-reduction flag. Interestingly this moves constants the opposite direction of the reassociate IR pass.

I've chosen to just punt on the reassociate, but I suppose we could maybe preserve the flag if both nodes have it set.

Differential Revision: https://reviews.llvm.org/D50827

llvm-svn: 339946
2018-08-16 21:54:05 +00:00
Chandler Carruth
c73c0307fe [MI] Change the array of MachineMemOperand pointers to be
a generically extensible collection of extra info attached to
a `MachineInstr`.

The primary change here is cleaning up the APIs used for setting and
manipulating the `MachineMemOperand` pointer arrays so chat we can
change how they are allocated.

Then we introduce an extra info object that using the trailing object
pattern to attach some number of MMOs but also other extra info. The
design of this is specifically so that this extra info has a fixed
necessary cost (the header tracking what extra info is included) and
everything else can be tail allocated. This pattern works especially
well with a `BumpPtrAllocator` which we use here.

I've also added the basic scaffolding for putting interesting pointers
into this, namely pre- and post-instruction symbols. These aren't used
anywhere yet, they're just there to ensure I've actually gotten the data
structure types correct. I'll flesh out support for these in
a subsequent patch (MIR dumping, parsing, the works).

Finally, I've included an optimization where we store any single pointer
inline in the `MachineInstr` to avoid the allocation overhead. This is
expected to be the overwhelmingly most common case and so should avoid
any memory usage growth due to slightly less clever / dense allocation
when dealing with >1 MMO. This did require several ergonomic
improvements to the `PointerSumType` to reasonably support the various
usage models.

This also has a side effect of freeing up 8 bits within the
`MachineInstr` which could be repurposed for something else.

The suggested direction here came largely from Hal Finkel. I hope it was
worth it. ;] It does hopefully clear a path for subsequent extensions
w/o nearly as much leg work. Lots of thanks to Reid and Justin for
careful reviews and ideas about how to do all of this.

Differential Revision: https://reviews.llvm.org/D50701

llvm-svn: 339940
2018-08-16 21:30:05 +00:00
Eli Friedman
73e8a784e6 [SelectionDAG] Improve the legalisation lowering of UMULO.
There is no way in the universe, that doing a full-width division in
software will be faster than doing overflowing multiplication in
software in the first place, especially given that this same full-width
multiplication needs to be done anyway.

This patch replaces the previous implementation with a direct lowering
into an overflowing multiplication algorithm based on half-width
operations.

Correctness of the algorithm was verified by exhaustively checking the
output of this algorithm for overflowing multiplication of 16 bit
integers against an obviously correct widening multiplication. Baring
any oversights introduced by porting the algorithm to DAG, confidence in
correctness of this algorithm is extremely high.

Following table shows the change in both t = runtime and s = space. The
change is expressed as a multiplier of original, so anything under 1 is
“better” and anything above 1 is worse.

+-------+-----------+-----------+-------------+-------------+
| Arch  | u64*u64 t | u64*u64 s | u128*u128 t | u128*u128 s |
+-------+-----------+-----------+-------------+-------------+
|   X64 |     -     |     -     |    ~0.5     |    ~0.64    |
|  i686 |   ~0.5    |   ~0.6666 |    ~0.05    |    ~0.9     |
| armv7 |     -     |   ~0.75   |      -      |    ~1.4     |
+-------+-----------+-----------+-------------+-------------+

Performance numbers have been collected by running overflowing
multiplication in a loop under `perf` on two x86_64 (one Intel Haswell,
other AMD Ryzen) based machines. Size numbers have been collected by
looking at the size of function containing an overflowing multiply in
a loop.

All in all, it can be seen that both performance and size has improved
except in the case of armv7 where code size has regressed for 128-bit
multiply. u128*u128 overflowing multiply on 32-bit platforms seem to
benefit from this change a lot, taking only 5% of the time compared to
original algorithm to calculate the same thing.

The final benefit of this change is that LLVM is now capable of lowering
the overflowing unsigned multiply for integers of any bit-width as long
as the target is capable of lowering regular multiplication for the same
bit-width. Previously, 128-bit overflowing multiply was the widest
possible.

Patch by Simonas Kazlauskas!

Differential Revision: https://reviews.llvm.org/D50310

llvm-svn: 339922
2018-08-16 18:39:39 +00:00
Simon Pilgrim
87d0039a45 [TargetLowering] Add support for non-uniform vectors to BuildSDIV
This patch refactors the existing TargetLowering::BuildSDIV base implementation to support non-uniform constant vector denominators.

This is the last patch necessary to close PR36545

Differential Revision: https://reviews.llvm.org/D50765

llvm-svn: 339908
2018-08-16 17:44:33 +00:00
Simon Pilgrim
ede4905375 [TargetLowering] Refactor BuildSDIV in preparation for D50765. NFCI.
Pull out magic factor calculators into a helper function, use 0/+1/-1 multiplication factor to (optionally) add/sub the numerator.

llvm-svn: 339898
2018-08-16 16:54:06 +00:00
Matt Arsenault
0f2c1cf429 DAG: Use getObjectOffset helper
llvm-svn: 339813
2018-08-15 21:03:44 +00:00
Matt Arsenault
22f01268fe DAG: Try to custom lower when promoting float operands
For some reason this wasn't done for floats like
integers.

llvm-svn: 339811
2018-08-15 20:34:54 +00:00
Simon Pilgrim
4b2317ebfb [TargetLowering] Minor cleanup of TargetLowering::BuildSDIV. NFCI.
Pull out some types to match layout in TargetLowering::BuildUDIV. Early step towards adding non-uniform vector support.

llvm-svn: 339763
2018-08-15 11:11:05 +00:00
Simon Pilgrim
a4ba43d3d3 [TargetLowering] Minor refactor to TargetLowering::BuildUDIV to merge scalar/vector magic value collection. NFCI.
Use the same ISD::matchUnaryPredicate pattern that was used in D50392.

llvm-svn: 339758
2018-08-15 10:11:13 +00:00
Simon Pilgrim
e8a906ba47 [DagCombiner] Don't bother adding to the work list if TLI.BuildSDIVPow2 failed. NFCI.
Matches the code in BuildSDIV/BuildUDIV

llvm-svn: 339757
2018-08-15 10:02:54 +00:00
Simon Pilgrim
a272fa9b0c [TargetLowering] Add support for non-uniform vectors to BuildExactSDIV
This patch refactors the existing BuildExactSDIV implementation to support non-uniform constant vector denominators.

Differential Revision: https://reviews.llvm.org/D50392

llvm-svn: 339756
2018-08-15 09:35:12 +00:00
Chandler Carruth
66654b72c9 [SDAG] Remove the reliance on MI's allocation strategy for
`MachineMemOperand` pointers attached to `MachineSDNodes` and instead
have the `SelectionDAG` fully manage the memory for this array.

Prior to this change, the memory management was deeply confusing here --
The way the MI was built relied on the `SelectionDAG` allocating memory
for these arrays of pointers using the `MachineFunction`'s allocator so
that the raw pointer to the array could be blindly copied into an
eventual `MachineInstr`. This creates a hard coupling between how
`MachineInstr`s allocate their array of `MachineMemOperand` pointers and
how the `MachineSDNode` does.

This change is motivated in large part by a change I am making to how
`MachineFunction` allocates these pointers, but it seems like a layering
improvement as well.

This would run the risk of increasing allocations overall, but I've
implemented an optimization that should avoid that by storing a single
`MachineMemOperand` pointer directly instead of allocating anything.
This is expected to be a net win because the vast majority of uses of
these only need a single pointer.

As a side-effect, this makes the API for updating a `MachineSDNode` and
a `MachineInstr` reasonably different which seems nice to avoid
unexpected coupling of these two layers. We can map between them, but we
shouldn't be *surprised* at where that occurs. =]

Differential Revision: https://reviews.llvm.org/D50680

llvm-svn: 339740
2018-08-14 23:30:32 +00:00
Cameron McInally
00b0658aae [FPEnv] Scalarize StrictFP vector operations
Add a helper function to scalarize constrained FP operations as needed.

Differential Revision: https://reviews.llvm.org/D50720

llvm-svn: 339735
2018-08-14 22:13:11 +00:00
Eli Friedman
0d12e90bf5 [ARM] Make PerformSHLSimplify add nodes to the DAG worklist correctly.
Intentionally excluding nodes from the DAGCombine worklist is likely to
lead to weird optimizations and infinite loops, so it's generally a bad
idea.

To avoid the infinite loops, fix DAGCombine to use the
isDesirableToCommuteWithShift target hook before performing the
transforms in question, and implement the target hook in the ARM backend
disable the transforms in question.

Fixes https://bugs.llvm.org/show_bug.cgi?id=38530 . (I don't have a
reduced testcase for that bug. But we should have sufficient test
coverage for PerformSHLSimplify given that we're not playing weird
tricks with the worklist. I can try to bugpoint it if necessary,
though.)

Differential Revision: https://reviews.llvm.org/D50667

llvm-svn: 339734
2018-08-14 22:10:25 +00:00
Nirav Dave
fbfe2ad9e0 [DAG] Avoid redundant chain transversal in store merge cycle check. NFCI.
Patch by Henric Karlsson.

llvm-svn: 339688
2018-08-14 16:20:43 +00:00
Scott Linder
35213793bc [CodeGen] Fix assert in SelectionDAG::computeKnownBits
Fix SelectionDAG::computeKnownBits asserting when handling EXTRACT_SUBVECTOR
when zero extending the demanded elements mask if it is already as long as the
source vector.

Differential Revision: https://reviews.llvm.org/D49574

llvm-svn: 339600
2018-08-13 18:44:21 +00:00
Simon Pilgrim
26e3d3f1c8 [DAGCombiner] simplifyDivRem - add comment describing divide by undef/zero combine. NFC.
llvm-svn: 339561
2018-08-13 13:12:25 +00:00
Craig Topper
cacf12a149 [SelectionDAG] In PromoteFloatOp_BITCAST, insert a bitcast after the fp_to_fp16 in case the result type isn't a scalar integer.
This is another variation of PR38533. In this case, the result type of the bitcast is legal and 16-bits wide, but not a scalar integer. So we need to emit the convert to i16 and then bitcast it to the true result type. This new bitcast will be further type legalized if necessary.

llvm-svn: 339536
2018-08-13 06:53:49 +00:00
Craig Topper
e42a159537 [SelectionDAG] In PromoteIntRes_BITCAST, when the input is TypePromoteFloat, make sure the output type is scalar. For vectors, use a store and load of temporary.
Previously if the result type was a vector, we emitted a FP_TO_FP16 with a vector result type which isn't valid.

This is basically the opposite case of the root cause of PR38533.

llvm-svn: 339535
2018-08-13 06:53:47 +00:00