Commit Graph

9317 Commits

Author SHA1 Message Date
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