Commit Graph

9513 Commits

Author SHA1 Message Date
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
Craig Topper 42e32117bb [SelectionDAG] In PromoteFloatRes_BITCAST, insert a bitcast before the fp16_to_fp in case the input type isn't an i16.
The bitcast can be further legalized as needed.

Fixes PR38533.

llvm-svn: 339533
2018-08-13 05:26:49 +00:00
Matt Arsenault 1201301b94 DAG: Check no-signed-zeros instead of unsafe-fp-math
Addresses fixme, although this should still be checking individual
operand flags.

llvm-svn: 339525
2018-08-12 19:09:12 +00:00
Craig Topper 60177f1aee [TargetLowering] Simplify one of the special cases in SimplifyDemandedBits for XOR. NFCI
We were checking for all bits being Known by checking Known.Zero|Known.One, but if all the bits are known then the value should be a Constant and we can just check for that instead.

llvm-svn: 339509
2018-08-12 06:52:03 +00:00
Craig Topper d112206004 [TargetLowering] Use APInt::isSubsetOf to simplify some code. NFC
llvm-svn: 339508
2018-08-12 05:34:15 +00:00
Sanjay Patel 15d1501aae [SelectionDAG] try harder to convert funnel shift to rotate
Similar to rL337966 - if the DAGCombiner's rotate matching was 
working as expected, I don't think we'd see any test diffs here.

AArch only goes right, and PPC only goes left. 
x86 has both, so no diffs there.

Differential Revision: https://reviews.llvm.org/D50091

llvm-svn: 339359
2018-08-09 17:26:22 +00:00
Michael Berg ca38254601 extend folding fsub/fadd to fneg for FMF
Summary: This change provides a common optimization path for both Unsafe and FMF driven optimization for this fsub fold adding reassociation, as it the flag that most closely represents the translation

Reviewers: spatel, wristow, arsenm

Reviewed By: spatel

Subscribers: wdng

Differential Revision: https://reviews.llvm.org/D50195

llvm-svn: 339357
2018-08-09 17:00:03 +00:00
Simon Pilgrim a9f95429d9 [TargetLowering] Add BuildSDIVPattern helper to BuildExactSDIV (NFCI).
As requested in D50392, pull the magic constant calculations out into a helper function.

llvm-svn: 339346
2018-08-09 13:56:04 +00:00
Sanjay Patel e47dc1a405 [DAGCombiner] loosen constraints for fsub+fadd fold
isNegatibleForFree() should not matter here (as the test diffs show)
because it's always a win to replace an fsub+fadd with fneg. The
problem in D50195 persists because either (1) we are doing these
folds in the wrong order or (2) we're missing another fold for fadd.

llvm-svn: 339299
2018-08-08 23:04:43 +00:00
Sanjay Patel e327266d45 [DAGCombiner] move fadd simplification ahead of other folds
I don't know if it's possible to expose this diff in a test,
but we should always try simplifications (no new nodes created)
before more complicated transforms for efficiency (similar to
what we do in IR).

llvm-svn: 339298
2018-08-08 22:46:30 +00:00
Simon Pilgrim 4d4220fa2a [DAG] DAGCombiner::visitSDIVLike - remove unnecessary isConstOrConstSplat call. NFCI.
The isConstOrConstSplat result is only used in a ISD::matchUnaryPredicate call which can perform the equivalent iteration just as quickly.

llvm-svn: 339262
2018-08-08 15:37:52 +00:00
Simon Pilgrim 164e8b0b5c [TargetLowering] BuildUDIV - Add support for divide by one (PR38477)
Provide a pass-through of the numerator for divide by one cases - this is the same approach we take in DAGCombiner::visitSDIVLike.

I investigated whether we could achieve this by magic MULHU/SRL values but nothing appeared to work as we don't have a way for MULHU(x,c) -> x

llvm-svn: 339254
2018-08-08 14:51:19 +00:00
Simon Pilgrim e4a4cf5a8b [TargetLowering] Remove APInt divisor argument from BuildExactSDIV (NFCI).
As requested in D50392, this is a minor refactor to BuildExactSDIV to stop taking the uniform constant APInt divisor and instead extract it locally.

I also cleanup the operands and valuetypes to better match BuildUDiv (and BuildSDIV in the near future).

llvm-svn: 339246
2018-08-08 13:59:44 +00:00
Ties Stuij 81f1fbdf5a test commit access
Summary: changing a few typos

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D50445

llvm-svn: 339245
2018-08-08 13:51:13 +00:00
Simon Pilgrim a10cfcc1db [TargetLowering] BuildUDIV - Early out for divide by one (PR38477)
We're not handling the UDIV by one special case properly - for now just early out.

llvm-svn: 339229
2018-08-08 10:00:54 +00:00
Thomas Preud'homme 4107b31df2 Support inline asm with multiple 64bit output in 32bit GPR
Summary: Extend fix for PR34170 to support inline assembly with multiple output operands that do not naturally go in the register class it is constrained to (eg. double in a 32-bit GPR as in the PR).

Reviewers: bogner, t.p.northover, lattner, javed.absar, efriedma

Reviewed By: efriedma

Subscribers: efriedma, tra, eraman, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D45437

llvm-svn: 339225
2018-08-08 09:35:26 +00:00
Craig Topper 49ed49fcb1 [SelectionDAG] When splitting scatter nodes during DAGCombine, create a serial chain dependency.
Scatter could have multiple identical indices. We need to maintain sequential order. We get this right in LegalizeVectorTypes, but not in this code.

Differential Revision: https://reviews.llvm.org/D50374

llvm-svn: 339157
2018-08-07 17:35:02 +00:00
Simon Pilgrim 1bfadb0499 [DAG] Allow non-uniform constant vectors to call BuildSDIV
This was missed in D50185.

NFC until we add actual non-uniform support to BuildSDIV (similar BuildUDIV support in D49248) - for now it just early outs.

llvm-svn: 339147
2018-08-07 14:50:39 +00:00
Simon Pilgrim 6943e39353 [TargetLowering] Use pre-computed Shift value type in BuildUDIV (NFCI)
This was missed in D49248

llvm-svn: 339146
2018-08-07 14:40:21 +00:00
Simon Pilgrim 7e18938793 [TargetLowering] Add support for non-uniform vectors to BuildUDIV
This patch refactors the existing TargetLowering::BuildUDIV base implementation to support non-uniform constant vector denominators.

It also includes a fold for MULHU by pow2 constants to SRL which can now more readily occur from BuildUDIV.

Differential Revision: https://reviews.llvm.org/D49248

llvm-svn: 339121
2018-08-07 09:51:34 +00:00
Craig Topper 9de1797c50 [SelectionDAG][X86] Rename MaskedLoadSDNode::getSrc0 to getPassThru.
Src0 doesn't really convey any meaning to what the operand is. Passthru matches what's used in the documentation for the intrinsic this comes from.

llvm-svn: 339101
2018-08-07 06:52:49 +00:00
Craig Topper 17989208a9 [SelectionDAG][X86] Rename getValue to getPassThru for gather SDNodes.
getValue is more meaningful name for scatter than it is for gather. Split them and use getPassThru for gather.

llvm-svn: 339096
2018-08-07 06:13:40 +00:00
Reid Kleckner 15e91c3235 [X86] Fix assertion in subreg extraction
This assert fires when attempting to extract a subregister from the
global PIC base register. This virtual register SD node is not in the
VRBaseMap, so we shouldn't call getVR to look it up there. If this is a
RegisterSDNode, we should be able to use the virtual register directly.

Fixes PR38385

llvm-svn: 339056
2018-08-06 21:16:16 +00:00
Hsiangkai Wang ef72e481ea [DebugInfo] Refactor DbgInfoIntrinsic class hierarchy.
In the past, DbgInfoIntrinsic has a strong assumption that these
intrinsics all have variables and expressions attached to them.
However, it is too strong to derive the class for other debug entities.
Now, it has problems for debug labels.

In order to make DbgInfoIntrinsic as a base class for 'debug info', I
create a class for 'variable debug info', DbgVariableIntrinsic.

DbgDeclareInst, DbgAddrIntrinsic, and DbgValueInst will be derived from it.

Differential Revision: https://reviews.llvm.org/D50220

llvm-svn: 338984
2018-08-06 03:59:47 +00:00
Craig Topper c4960582ec [SelectionDAG] Teach LegalizeVectorTypes to widen the mask input to a masked store.
The mask operand is visited before the data operand so we need to be able to widen it.

Fixes PR38436.

llvm-svn: 338915
2018-08-03 20:14:18 +00:00
Matt Arsenault c3dc8e65e2 DAG: Enhance isKnownNeverNaN
Add a parameter for testing specifically for
sNaNs - at least one instruction pattern on AMDGPU
needs to check specifically for this.

Also handle more cases, and add a target hook
for custom nodes, similar to the hooks for known
bits.

llvm-svn: 338910
2018-08-03 18:27:52 +00:00
Simon Pilgrim 94112ebc75 [TargetLowering] Generalise BuildSDIV function
First step towards a BuildSDIV equivalent to D49248 for non-uniform vector support - this just pushes the splat detection down into TargetLowering::BuildSDIV where its still used.

Differential Revision: https://reviews.llvm.org/D50185

llvm-svn: 338838
2018-08-03 10:00:54 +00:00
Matt Arsenault 1f3977a856 DAG: Fix vector widening fcanonicalize
llvm-svn: 338715
2018-08-02 13:43:53 +00:00
Lei Liu b9a7b7a84d Fix FCOPYSIGN expansion
In expansion of FCOPYSIGN, the shift node is missing when the two
operands of FCOPYSIGN are of the same size. We should always generate
shift node (if the required shift bit is not zero) to put the sign
bit into the right position, regardless of the size of underlying
types.

Differential Revision: https://reviews.llvm.org/D49973

llvm-svn: 338665
2018-08-02 01:54:12 +00:00
Michael Berg d3ce4c3d94 [NFC] small addendum to r334242, FMF propagation
llvm-svn: 338604
2018-08-01 18:06:49 +00:00
Sanjay Patel 8aac22e06a [SelectionDAG] fix bug in translating funnel shift with non-power-of-2 type
The bug is visible in the constant-folded x86 tests. We can't use the
negated shift amount when the type is not power-of-2:
https://rise4fun.com/Alive/US1r

...so in that case, use the regular lowering that includes a select
to guard against a shift-by-bitwidth. This path is improved by only
calculating the modulo shift amount once now.

Also, improve the rotate (with power-of-2 size) lowering to use
a negate rather than subtract from bitwidth. This improves the
codegen whether we have a rotate instruction or not (although
we can still see that we're not matching to a legal rotate in
all cases).

llvm-svn: 338592
2018-08-01 17:17:08 +00:00
Simon Pilgrim a3548c960e [SelectionDAG] Make binop reduction matcher available to all targets
There is nothing x86-specific about this code, so it'd be nice to make this available for other targets to use in the future (and get it out of X86ISelLowering!).

Differential Revision: https://reviews.llvm.org/D50083

llvm-svn: 338586
2018-08-01 16:52:28 +00:00
Cameron McInally 04ae85859d [FPEnv] Widen illegal width StrictFP vector operations as needed
Differential Revision: https://reviews.llvm.org/D49806

llvm-svn: 338562
2018-08-01 14:17:19 +00:00
Matt Arsenault dcec0888e2 DAG: Correct pointer type used for stack slot
Correct the address space for the inserted argument
stack slot.

AMDGPU seems to not do anything with this information,
so I don't think this was breaking anything.

llvm-svn: 338428
2018-07-31 19:51:20 +00:00
Matt Arsenault a5ed032118 DAG: Fix PromoteFloatResult for fcanonicalize
llvm-svn: 338382
2018-07-31 14:15:22 +00:00
Hsiangkai Wang 615540d0f2 Test commit.
llvm-svn: 338352
2018-07-31 06:09:29 +00:00
Craig Topper 2f60ef2c78 [DAGCombiner][TargetLowering] Pass a SmallVector instead of a std::vector to BuildSDIV/BuildUDIV/etc.
The vector contains the SDNodes that these functions create. The number of nodes is always a small number so we should use SmallVector to avoid a heap allocation.

llvm-svn: 338329
2018-07-30 23:22:00 +00:00
Sanjay Patel 9f807f44b1 [DAGCombiner] transform sub-of-shifted-signbit to add
This is exchanging a sub-of-1 with add-of-minus-1:
https://rise4fun.com/Alive/plKAH

This is another step towards improving select-of-constants codegen (see D48970).

x86 is the motivating target, and those diffs all appear to be wins. PPC and AArch64 look neutral.
I've limited this to early combining (!LegalOperations) in case a target wants to reverse it, but
I think canonicalizing to 'add' is more likely to produce further transforms because we have more
folds for 'add'.

Differential Revision: https://reviews.llvm.org/D49924

llvm-svn: 338317
2018-07-30 22:21:37 +00:00
Craig Topper 42d312bb83 [TargetLowering] In BuildSDIV, add the MULHS/SMUL_LOHI to the Created vector.
BuildUDIV was already correct.

llvm-svn: 338304
2018-07-30 21:04:38 +00:00
Craig Topper a568a27dfa [DAGCombiner][PowerPC][AArch64] Pass Created vector by reference to BuildSDIVPow2.
llvm-svn: 338303
2018-07-30 21:04:34 +00:00
Craig Topper b94d5f853b Revert r338222 "[DAGCombiner] Remove unnecessary calls to AddToWorklist."
Thinking about it more it might be possible for the later nodes to be folded in getNode in such a way that the other created nodes are left dead. This can cause use counts to be incorrect on nodes that aren't dead.

So its probably safer to leave this alone.

llvm-svn: 338298
2018-07-30 20:27:10 +00:00
Fangrui Song f78650a8de Remove trailing space
sed -Ei 's/[[:space:]]+$//' include/**/*.{def,h,td} lib/**/*.{cpp,h}

llvm-svn: 338293
2018-07-30 19:41:25 +00:00
David Bolvansky 2fa7fb14ea [DAGCombiner] Bug 31275- Extract a shift from a constant mul or udiv if a rotate can be formed
Summary:
Attempt to extract a shrl from a udiv or a shl from a mul if this allows a rotate to be formed.  This targets cases where the input to a rotate pattern was a mul or udiv by a constant and InstCombine merged one of the shifts with the op.

Patch by: sameconrad (Sam Conrad)

Reviewers: RKSimon, craig.topper, spatel, lebedev.ri, javed.absar

Reviewed By: lebedev.ri

Subscribers: efriedma, kparzysz, llvm-commits

Differential Revision: https://reviews.llvm.org/D47681

llvm-svn: 338270
2018-07-30 16:50:00 +00:00
Thomas Preud'homme 196149c943 Reapply "Fix crash on inline asm with 64bit matching input in 32bit GPR"
This reapplies commit r338206 reverted by r338214 since the bug that
r338206 uncovered has been fixed in r338268.

Add support for inline assembly with matching input operand that do not
naturally go in the register class it is constrained to (eg. double in a
32-bit GPR). Note that regular input is already handled by existing
code.

llvm-svn: 338269
2018-07-30 16:48:39 +00:00
Craig Topper e978d2ee4a [DAGCombiner] Remove unnecessary calls to AddToWorklist.
The DAGCombiner has a mechanism for ensuring all nodes have been visited at least once. Every time a node is visited, it makes sure its operands have been in the worklist at least once. This ensures that when multiple nodes are created by a combine, only the last node needs to be returned. The earlier nodes can all be found Through this operand check. These means we don't need to explicitly add nodes to the worklist when a combine creates multiple nodes.

I've removed the most obvious cases here. There are probably more than can be removed.

llvm-svn: 338222
2018-07-29 18:39:26 +00:00
Sanjay Patel 7312206f2f revert r338206 because the test does not pass
Example of bot failure:
http://lab.llvm.org:8011/builders/clang-cmake-armv8-quick/builds/5107/steps/ninja%20check%201/logs/FAIL%3A%20LLVM%3A%3Ainline-asm-operand-implicit-cast.ll

llvm-svn: 338214
2018-07-29 14:30:49 +00:00
Thomas Preud'homme 74ffd14e15 Fix crash on inline asm with 64bit matching input in 32bit GPR
Add support for inline assembly with matching input operand that do not
naturally go in the register class it is constrained to (eg. double in a
32-bit GPR). Note that regular input is already handled by existing
code.

llvm-svn: 338206
2018-07-28 21:33:39 +00:00
Craig Topper 9db3573d3a [SelectionDAG] Pass std::vector by reference instead of by pointer to BuildSDIV/BuildUDIV.
This removes the need for an assert to ensure the pointer isn't null.

Years ago we had ifs the checked the pointer was non-null before very access to the vector. These checks were removed and replaced with a single assert. But a reference seems more suitable here.

llvm-svn: 338205
2018-07-28 19:44:20 +00:00
Matt Arsenault 81920b0a25 DAG: Add calling convention argument to calling convention funcs
This seems like a pretty glaring omission, and AMDGPU
wants to treat kernels differently from other calling
conventions.

llvm-svn: 338194
2018-07-28 13:25:19 +00:00
Craig Topper 50b1d4303d [DAGCombiner] Teach DAG combiner that A-(B-C) can be folded to A+(C-B)
This can be useful since addition is commutable, and subtraction is not.

This matches a transform that is also done by InstCombine.

llvm-svn: 338181
2018-07-28 00:27:25 +00:00
Sanjay Patel c7abb416dc [DAGCombiner] fold 'not' with signbit math
This is a follow-up suggested in D48970. 

Alive proofs:
https://rise4fun.com/Alive/sII

We can eliminate an instruction in the usual select-of-constants 
to bit hack transform by adjusting the add/sub with constant.
This is always a win. 

There are more transforms that are likely wins, but they may need 
target hooks in case some targets do not benefit. 

This is another step towards making up for canonicalizing to 
select-of-constants in rL331486.

llvm-svn: 338132
2018-07-27 16:42:55 +00:00
Matt Arsenault 611dff423c DAG: Remove unnecessary .str()
llvm-svn: 338112
2018-07-27 09:04:41 +00:00
Craig Topper 1a40a06549 [SelectionDAGBuilder] Add masked loads to PendingLoads rather than calling DAG.setRoot.
Masked loads are calling DAG.getRoot rather than calling SelectionDAGBuilder::getRoot, which means the PendingLoads weren't emptied to update the root and create any needed TokenFactor. So it would be incorrect to call setRoot for the masked load.

This patch instead adds the masked load to PendingLoads so that the root doesn't get update until a store or scatter or something happens.. Alternatively, we could call SelectionDAGBuilder::getRoot before it, but that would create unnecessary serialization.

llvm-svn: 338085
2018-07-26 23:22:11 +00:00
Craig Topper 8da280f50b [SelectionDAG] Add MLOAD/MSTORE/MGATHER/MSCATTER to AddNodeIDCustom to properly calculate their folding set ID to allow them to be CSEd.
llvm-svn: 338080
2018-07-26 22:40:24 +00:00
Craig Topper 8b5a2f7aac [DAGCombiner] Remove some calls to AddToWorklist that should be unnecessary.
The DAGCombiner has a system for ensuring all nodes are visited. It doesn't require an AddToWorkList for every node that is created by a combine.

llvm-svn: 338079
2018-07-26 22:40:22 +00:00
Vedant Kumar b572f64212 [DebugInfo] LowerDbgDeclare: Add derefs when handling CallInst users
LowerDbgDeclare inserts a dbg.value before each use of an address
described by a dbg.declare. When inserting a dbg.value before a CallInst
use, however, it fails to append DW_OP_deref to the DIExpression.

The DW_OP_deref is needed to reflect the fact that a dbg.value describes
a source variable directly (as opposed to a dbg.declare, which relies on
pointer indirection).

This patch adds in the DW_OP_deref where needed. This results in the
correct values being shown during a debug session for a program compiled
with ASan and optimizations (see https://reviews.llvm.org/D49520). Note
that ConvertDebugDeclareToDebugValue is already correct -- no changes
there were needed.

One complication is that SelectionDAG is unable to distinguish between
direct and indirect frame-index (FRAMEIX) SDDbgValues. This patch also
fixes this long-standing issue in order to not regress integration tests
relying on the incorrect assumption that all frame-index SDDbgValues are
indirect. This is a necessary fix: the newly-added DW_OP_derefs cannot
be lowered properly otherwise. Basically the fix prevents a direct
SDDbgValue with DIExpression(DW_OP_deref) from being dereferenced twice
by a debugger. There were a handful of tests relying on this incorrect
"FRAMEIX => indirect" assumption which actually had incorrect
DW_AT_locations: these are all fixed up in this patch.

Testing:

- check-llvm, and an end-to-end test using lldb to debug an optimized
  program.
- Existing unit tests for DIExpression::appendToStack fully cover the
  new DIExpression::append utility.
- check-debuginfo (the debug info integration tests)

Differential Revision: https://reviews.llvm.org/D49454

llvm-svn: 338069
2018-07-26 20:56:53 +00:00
Roman Lebedev 41ba5c1455 [DAGCombine] optimizeSetCCOfSignedTruncationCheck(): handle ule,ugt CondCodes.
Summary:
A follow-up for D49266 / rL337166.

At least one of these cases is more canonical,
so we really do have to handle it.
https://godbolt.org/g/pkzP3X
https://rise4fun.com/Alive/pQyhZZ

We won't get to these cases with I1 being -1,
as that will be constant-folded to true or false.

I'm also not sure we actually hit the 'ule' case,
but i think the worst think that could happen is that being dead code.

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

Reviewed By: spatel

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D49497

llvm-svn: 338044
2018-07-26 17:34:28 +00:00
Sanjay Patel 215dcbf4db [SelectionDAG] try to convert funnel shift directly to rotate if legal
If the DAGCombiner's rotate matching was working as expected, 
I don't think we'd see any test diffs here. 

This sidesteps the issue of custom lowering for rotates raised in PR38243:
https://bugs.llvm.org/show_bug.cgi?id=38243
...by only dealing with legal operations.

llvm-svn: 337966
2018-07-25 21:38:30 +00:00
Ulrich Weigand 5f75371c5d Fix corruption of result number in LegalizeVectorOps.cpp
When VectorLegalizer::LegalizeOp creates a new SDValue after iterating
over its arguments, we need to refer to the same result number of the
new node that the original value used.

Reviewed by: cameron.mcinally

Differential Revision: https://reviews.llvm.org/D49805

llvm-svn: 337939
2018-07-25 17:08:13 +00:00
Thomas Preud'homme 768d6ce4a3 Fix PR34170: Crash on inline asm with 64bit output in 32bit GPR
Add support for inline assembly with output operand that do not
naturally go in the register class it is constrained to (eg. double in a
32-bit GPR as in the PR).

llvm-svn: 337903
2018-07-25 11:11:12 +00:00
Vedant Kumar 22bd6f99fa [SelectionDAG] Reduce DanglingDebugInfo memory traffic, NFC
This avoids approx. 2 x 10^5 DenseMap insertions in both non-debug and
debug -O2 builds of the sqlite3 amalgamation.

llvm-svn: 337751
2018-07-23 21:59:04 +00:00
Nirav Dave eac2ca4e28 [Legalize] Elide MERGE_VALUES created by scalarizeVectorLoad.
scalarizeVectorLoad creates MERGE_VALUES nodes which are immediately
decomposed in expandLoad. Elide the node in these cases.

llvm-svn: 337708
2018-07-23 16:43:42 +00:00
Cameron McInally 2c9bcffc92 [FPEnv] Legalize double width StrictFP vector operations
Differential Revision: https://reviews.llvm.org/D48809

llvm-svn: 337698
2018-07-23 14:40:17 +00:00
Craig Topper b8b21d2fca [SelectionDAGBuilder] Use APInt::isZero instead of comparing APInt::getZExtValue to 0 in a place where we can't be sure contents of the APInt fit in a uint64_t.
This is used on an extract vector element index which is most cases is going to be an i32 or i64 and the element will be a valid element number. But it is possible to construct IR with a larger type and large out of range value.

llvm-svn: 337652
2018-07-22 05:16:50 +00:00
Craig Topper bf61113e4f [SelectionDAGBuilder] Restrict vector reduction check to types with a power of 2 number of elements.
The check for the shuffles usages probably isn't correct for non power of 2 vectors.

llvm-svn: 337651
2018-07-22 05:16:49 +00:00
Nirav Dave 25802ac9fd [DAG] Avoid Node Update assertion due to AND simplification
Check for construction-time folding for incomplete AND nodes in
BackwardsPropagateMask.

Fixes PR38185.

Reviewers: RKSimon, samparker

Reviewed By: samparker

Subscribers: llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D49444

llvm-svn: 337563
2018-07-20 15:27:24 +00:00
Nirav Dave 5a4e11ad9c [DAG] Fix Memory ordering check in ReduceLoadOpStore.
When merging through a TokenFactor we need to check that the
load may be ordered such that no other aliasing memory operations may
happen. It is not sufficient to just check that the load is a member
of the chain token factor as it there may be a indirect chain. Require
the load's chain has only one use.

This fixes PR37826.

Reviewers: spatel, davide, efriedma, craig.topper, RKSimon

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D49388

llvm-svn: 337560
2018-07-20 15:20:50 +00:00
Craig Topper d8734450a2 [DAGCombiner] Fold X - (-Y *Z) -> X + (Y * Z)
llvm-svn: 337518
2018-07-20 01:40:03 +00:00
Stephen Canon 8995c5f0f6 Skip out of SimplifyDemandedBits for BITCAST of f16 to i16
Mirrors the existing exit path for f128, avoiding a crash later on.

Differential Revision: https://reviews.llvm.org/D49524

llvm-svn: 337506
2018-07-19 22:46:42 +00:00
Craig Topper c12c5d421f [DAGCombiner] Teach DAGCombiner that A-(-B) is A+B.
We already knew A+(-B) is A-B in visitAdd. This does the opposite for visitSub.

llvm-svn: 337502
2018-07-19 22:24:43 +00:00
Nirav Dave a747d3ca60 [ScheduleDAG] Fix unfolding of SUnits to already existent nodes.
Summary:
If unfolding an SUnit results in both load or the operation using it which
already exist in the DAG, abort the unfold if they are already scheduled.
If not, make sure we don't add duplicate dependencies.

This fixes PR37916.

Reviewers: davide, eli.friedman, fhahn, bogner

Subscribers: MatzeB, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D48666

llvm-svn: 337409
2018-07-18 18:01:03 +00:00
Simon Pilgrim e4d12bb2d6 [DAGCombiner] Call SimplifyDemandedVectorElts from EXTRACT_VECTOR_ELT
If we are only extracting vector elements via EXTRACT_VECTOR_ELT(s) we may be able to use SimplifyDemandedVectorElts to avoid unnecessary vector ops.

Differential Revision: https://reviews.llvm.org/D49262

llvm-svn: 337258
2018-07-17 09:45:35 +00:00
Sanjay Patel c71adc8040 [Intrinsics] define funnel shift IR intrinsics + DAG builder support
As discussed here:
http://lists.llvm.org/pipermail/llvm-dev/2018-May/123292.html
http://lists.llvm.org/pipermail/llvm-dev/2018-July/124400.html

We want to add rotate intrinsics because the IR expansion of that pattern is 4+ instructions, 
and we can lose pieces of the pattern before it gets to the backend. Generalizing the operation 
by allowing 2 different input values (plus the 3rd shift/rotate amount) gives us a "funnel shift" 
operation which may also be a single hardware instruction.

Initially, I thought we needed to define new DAG nodes for these ops, and I spent time working 
on that (much larger patch), but then I concluded that we don't need it. At least as a first 
step, we have all of the backend support necessary to match these ops...because it was required. 
And shepherding these through the IR optimizer is the primary concern, so the IR intrinsics are 
likely all that we'll ever need.

There was also a question about converting the intrinsics to the existing ROTL/ROTR DAG nodes
(along with improving the oversized shift documentation). Again, I don't think that's strictly 
necessary (as the test results here prove). That can be an efficiency improvement as a small 
follow-up patch.

So all we're left with is documentation, definition of the IR intrinsics, and DAG builder support. 

Differential Revision: https://reviews.llvm.org/D49242

llvm-svn: 337221
2018-07-16 22:59:31 +00:00
Fangrui Song cb0bab86b3 [CodeGen] Fix inconsistent declaration parameter name
llvm-svn: 337200
2018-07-16 18:51:40 +00:00
Roman Lebedev de506632aa [X86][AArch64][DAGCombine] Unfold 'check for [no] signed truncation' pattern
Summary:

[[ https://bugs.llvm.org/show_bug.cgi?id=38149 | PR38149 ]]

As discussed in https://reviews.llvm.org/D49179#1158957 and later,
the IR for 'check for [no] signed truncation' pattern can be improved:
https://rise4fun.com/Alive/gBf
^ that pattern will be produced by Implicit Integer Truncation sanitizer,
https://reviews.llvm.org/D48958 https://bugs.llvm.org/show_bug.cgi?id=21530
in signed case, therefore it is probably a good idea to improve it.

But the IR-optimal patter does not lower efficiently, so we want to undo it..

This handles the simple pattern.
There is a second pattern with predicate and constants inverted.

NOTE: we do not check uses here. we always do the transform.

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

Reviewed By: spatel

Subscribers: kristof.beyls, llvm-commits

Differential Revision: https://reviews.llvm.org/D49266

llvm-svn: 337166
2018-07-16 12:44:10 +00:00
Daniel Cederman c3d8002c2e Avoid losing Hi part when expanding VAARG nodes on big endian machines
Summary:
If the high part of the load is not used the offset to the next element
will not be set correctly.

For example, on Sparc V8, the following code will read val2 from offset 4
instead of 8.

```
int val = __builtin_va_arg(va, long long);
int val2 = __builtin_va_arg(va, int);
```

Reviewers: jyknight

Reviewed By: jyknight

Subscribers: fedor.sergeev, jrtc27, llvm-commits

Differential Revision: https://reviews.llvm.org/D48595

llvm-svn: 337161
2018-07-16 12:14:17 +00:00
Sanjay Patel 79a423cfa2 [DAGCombiner] fix typo in comment; NFC
llvm-svn: 337132
2018-07-15 17:09:35 +00:00
Sanjay Patel a41c886c55 [DAGCombiner] extend(ifpositive(X)) -> shift-right (not X)
This is almost the same as an existing IR canonicalization in instcombine, 
so I'm assuming this is a good early generic DAG combine too.

The motivation comes from reduced bit-hacking for select-of-constants in IR 
after rL331486. We want to restore that functionality in the DAG as noted in
the commit comments for that change and the llvm-dev discussion here:
http://lists.llvm.org/pipermail/llvm-dev/2018-July/124433.html

The PPC and AArch tests show that those targets are already doing something 
similar. x86 will be neutral in the minimal case and generally better when 
this pattern is extended with other ops as shown in the signbit-shift.ll tests.

Note the asymmetry: we don't include the (extend (ifneg X)) transform because 
it already exists in SimplifySelectCC(), and that is verified in the later 
unchanged tests in the signbit-shift.ll files. Without the 'not' op, the 
general transform to use a shift is always a win because that's a single 
instruction.

Alive proofs:
https://rise4fun.com/Alive/ysli

Name: if pos, get -1
  %c = icmp sgt i16 %x, -1
  %r = sext i1 %c to i16
  =>
  %n = xor i16 %x, -1
  %r = ashr i16 %n, 15

Name: if pos, get 1
  %c = icmp sgt i16 %x, -1
  %r = zext i1 %c to i16
  =>
  %n = xor i16 %x, -1
  %r = lshr i16 %n, 15

Differential Revision: https://reviews.llvm.org/D48970

llvm-svn: 337130
2018-07-15 16:27:07 +00:00
Matthias Braun 90ad6835dd CodeGen: Remove pipeline dependencies on StackProtector; NFC
This re-applies r336929 with a fix to accomodate for the Mips target
scheduling multiple SelectionDAG instances into the pass pipeline.

PrologEpilogInserter and StackColoring depend on the StackProtector analysis
being alive from the point it is run until PEI, which requires that they are all
scheduled in the same FunctionPassManager. Inserting a (machine) ModulePass
between StackProtector and PEI results in these passes being in separate
FunctionPassManagers and the StackProtector is not available for PEI.

PEI and StackColoring don't use much information from the StackProtector pass,
so transfering the required information to MachineFrameInfo is cleaner than
keeping the StackProtector pass around. This commit moves the SSP layout
information to MFI instead of keeping it in the pass.

This patch set (D37580, D37581, D37582, D37583, D37584, D37585, D37586, D37587)
is a first draft of the pagerando implementation described in
http://lists.llvm.org/pipermail/llvm-dev/2017-June/113794.html.

Patch by Stephen Crane <sjc@immunant.com>

Differential Revision: https://reviews.llvm.org/D49256

llvm-svn: 336964
2018-07-13 00:08:38 +00:00
Matthias Braun f03f32d478 Revert "(HEAD -> master, origin/master, arcpatch-D37582) CodeGen: Remove pipeline dependencies on StackProtector; NFC"
This was triggering pass scheduling failures.

This reverts commit r336929.

llvm-svn: 336934
2018-07-12 19:27:01 +00:00
Matthias Braun 9436570cbd CodeGen: Remove pipeline dependencies on StackProtector; NFC
PrologEpilogInserter and StackColoring depend on the StackProtector analysis
being alive from the point it is run until PEI, which requires that they are all
scheduled in the same FunctionPassManager. Inserting a (machine) ModulePass
between StackProtector and PEI results in these passes being in separate
FunctionPassManagers and the StackProtector is not available for PEI.

PEI and StackColoring don't use much information from the StackProtector pass,
so transfering the required information to MachineFrameInfo is cleaner than
keeping the StackProtector pass around. This commit moves the SSP layout
information to MFI instead of keeping it in the pass.

This patch set (D37580, D37581, D37582, D37583, D37584, D37585, D37586, D37587)
is a first draft of the pagerando implementation described in
http://lists.llvm.org/pipermail/llvm-dev/2017-June/113794.html.

Patch by Stephen Crane <sjc@immunant.com>

Differential Revision: https://reviews.llvm.org/D49256

llvm-svn: 336929
2018-07-12 18:33:32 +00:00
Eli Friedman 0319c28459 [CodeGen] Emit more precise AssertZext/AssertSext nodes.
This is marginally helpful for removing redundant extensions, and the
code is easier to read, so it seems like an all-around win. In the new
test i8-phi-ext.ll, we used to emit an AssertSext i8; now we emit an
AssertZext i2, which allows the extension of the return value to be
eliminated.

Differential Revision: https://reviews.llvm.org/D49004

llvm-svn: 336868
2018-07-11 23:26:35 +00:00
Diogo N. Sampaio b0d85ef975 [NFC][InstCombine] Converts isLegalNarrowLoad into isLegalNarrowLdSt
Reuse this function as to test correctness and profitability of
reducing width of either load or store operations.

Reviewsers: samparker

Differential Revision: https://reviews.llvm.org/D48624

llvm-svn: 336800
2018-07-11 12:59:42 +00:00
Simon Pilgrim 075b04a55f [SelectionDAG] Add constant buildvector support to isKnownNeverZero
This allows us to use SelectionDAG::isKnownNeverZero in DAGCombiner::visitREM (visitSDIVLike/visitUDIVLike handle the checking for constants).

llvm-svn: 336779
2018-07-11 09:56:41 +00:00
Simon Pilgrim df9d59771b [DAGCombiner] Support non-uniform X%C -> X-(X/C)*C folds
First stage in PR38057 - support non-uniform constant vectors in the combine to reuse the division-by-constant logic.

We can definitely do better for srem pow2 remainders (and avoid that extra multiply....) but this at least helps keep everything on the vector unit.

Differential Revision: https://reviews.llvm.org/D48975

llvm-svn: 336774
2018-07-11 09:22:42 +00:00
Simon Pilgrim 97cf111689 [DAGCombiner] Add (urem X, -1) -> select(X == -1, 0, x) fold
llvm-svn: 336773
2018-07-11 09:14:37 +00:00
Simon Pilgrim 4cb4609392 [DAGCombiner] Add special case fast paths for udiv x,1 and udiv x,-1
udiv x,-1 was going down the (slow) BuildUDIV route resulting in unnecessary shifts.

llvm-svn: 336701
2018-07-10 16:33:07 +00:00
Simon Pilgrim 641097d561 [DAGCombiner] visitREM - call visitSDIVLike/visitUDIVLike directly to avoid recursive combining.
As suggested by @efriedma on D48975 use the visitSDIVLike/visitUDIVLike functions introduced at rL336656.

llvm-svn: 336664
2018-07-10 13:18:16 +00:00
Simon Pilgrim ce5c19b623 [DAGCombiner] Split SDIV/UDIV optimization expansions from the rest of the combines. NFCI.
As suggested by @efriedma on D48975, this patch separates the BuildDiv/Pow2 style optimizations from the rest of the visitSDIV/visitUDIV to make it easier to reuse the combines and will allow us to avoid some rather nasty node recursive combining in visitREM.

llvm-svn: 336656
2018-07-10 11:38:00 +00:00
Roman Lebedev 5ccae1750b [X86][TLI] DAGCombine: Unfold variable bit-clearing mask to two shifts.
Summary:
This adds a reverse transform for the instcombine canonicalizations
that were added in D47980, D47981.

As discussed later, that was worse at least for the code size,
and potentially for the performance, too.

https://rise4fun.com/Alive/Zmpl

Reviewers: craig.topper, RKSimon, spatel

Reviewed By: spatel

Subscribers: reames, llvm-commits

Differential Revision: https://reviews.llvm.org/D48768

llvm-svn: 336585
2018-07-09 19:06:42 +00:00
Craig Topper e3b0c7e5bd [SelectionDAG] Add VT consistency checks to the creation of ISD::FMA.
This is similar to what is done for binops. I don't know if this would have helped us catch the bug fixed in r336566 earlier or not, but I figured it couldn't hurt.

llvm-svn: 336576
2018-07-09 18:23:55 +00:00
Simon Pilgrim 23f9eddabe [SelectionDAG] Split float and integer isKnownNeverZero tests
Splits off isKnownNeverZeroFloat to handle +/- 0 float cases.

This will make it easier to be more aggressive with the integer isKnownNeverZero tests (similar to ValueTracking), use computeKnownBits etc.

Differential Revision: https://reviews.llvm.org/D48969

llvm-svn: 336492
2018-07-07 18:17:14 +00:00
Simon Pilgrim 0a36daa5a2 Use const APInt& to avoid extra copy. NFCI.
As discussed on D48825.

llvm-svn: 336491
2018-07-07 17:33:48 +00:00
Simon Pilgrim c1d1944053 [DAGCombiner] Add EXTRACT_SUBVECTOR to SimplifyDemandedVectorElts
As discussed on PR37989, this patch adds EXTRACT_SUBVECTOR handling to TargetLowering::SimplifyDemandedVectorElts and calls it from DAGCombiner::visitEXTRACT_SUBVECTOR.

Differential Revision: https://reviews.llvm.org/D48825

llvm-svn: 336490
2018-07-07 17:30:06 +00:00
Nico Weber 038dbf3c24 Revert 336426 (and follow-ups 428, 440), it very likely caused PR38084.
llvm-svn: 336453
2018-07-06 17:37:24 +00:00
Diogo N. Sampaio 17be994942 Added missing semicolon
llvm-svn: 336428
2018-07-06 10:09:04 +00:00
Diogo N. Sampaio 742bf1a255 [SelectionDAG] https://reviews.llvm.org/D48278
D48278

Allow to reduce redundant shift masks.
For example:
x1 = x & 0xAB00
x2 = (x >> 8) & 0xAB

can be reduced to:
x1 = x & 0xAB00
x2 = x1 >> 8
It only allows folding when the masks and shift values are constants.

llvm-svn: 336426
2018-07-06 09:42:25 +00:00
Diogo N. Sampaio 734cfd11fe Testing commit permision
llvm-svn: 336384
2018-07-05 18:49:32 +00:00
Simon Pilgrim 74cc4cfa94 [DAGCombiner] visitSDIV - Permit MIN_SIGNED_VALUE in pow2 vector codegen
Now that D45806 has landed, we can re-enable support for MIN_SIGNED_VALUE in the sdiv by pow2-constant code

llvm-svn: 336198
2018-07-03 14:11:32 +00:00
Piotr Padlewski 5b3db45e8f Implement strip.invariant.group
Summary:
This patch introduce new intrinsic -
strip.invariant.group that was described in the
RFC: Devirtualization v2

Reviewers: rsmith, hfinkel, nlopes, sanjoy, amharc, kuhar

Subscribers: arsenm, nhaehnle, JDevlieghere, hiraditya, xbolva00, llvm-commits

Differential Revision: https://reviews.llvm.org/D47103

Co-authored-by: Krzysztof Pszeniczny <krzysztof.pszeniczny@gmail.com>
llvm-svn: 336073
2018-07-02 04:49:30 +00:00
Simon Pilgrim fae337704e [DAGCombiner] Handle correctly non-splat power of 2 -1 divisor (PR37119)
The combine added in commit 329525 overlooked the case where one, but not all, of the divisor elements is -1, -1 is the only power of two value for which the sdiv expansion recipe breaks.

Thanks to @zvi for the original patch.

Differential Revision: https://reviews.llvm.org/D45806

llvm-svn: 336048
2018-06-30 12:22:55 +00:00
Simon Pilgrim 9c70d48cb2 [DAGCombiner] Ensure we use the correct CC result type in visitSDIV (REAPPLIED)
We could get away with it for constant folded cases, but not for rL335719.

Thanks to Krzysztof Parzyszek for noticing.

Reapply original commit rL335821 which was reverted at rL335871 due to a WebAssembly bug that was fixed at rL335884.

llvm-svn: 335886
2018-06-28 17:33:41 +00:00
Matthias Braun da5e7e11d1 SelectionDAGBuilder, mach-o: Skip trap after noreturn call (for Mach-O)
Add NoTrapAfterNoreturn target option which skips emission of traps
behind noreturn calls even if TrapUnreachable is enabled.

Enable the feature on Mach-O to save code size; Comments suggest it is
not possible to enable it for the other users of TrapUnreachable.

rdar://41530228

DifferentialRevision: https://reviews.llvm.org/D48674
llvm-svn: 335877
2018-06-28 17:00:45 +00:00
Haojian Wu 2103990e63 Revert "[DAGCombiner] Ensure we use the correct CC result type in visitSDIV"
This reverts commit r335821.

This crashes the webassembly test, run "ninja check-llvm-codegen-webassembly" to reproduce.

llvm-svn: 335871
2018-06-28 16:25:57 +00:00
Simon Pilgrim abebe4c746 [DAGCombiner] Ensure we use the correct CC result type in visitSDIV
We could get away with it for constant folded cases, but not for rL335719.

Thanks to Krzysztof Parzyszek for noticing.

llvm-svn: 335821
2018-06-28 09:54:28 +00:00
Simon Pilgrim 49cb65bb7b [DAGCombiner] Remove unused variable. NFCI.
Noticed in D45806 review.

llvm-svn: 335817
2018-06-28 09:29:08 +00:00
Nirav Dave 7c57ae57a8 [DAGCombine] Disable TokenFactor simplifications when optnone.
llvm-svn: 335773
2018-06-27 19:41:25 +00:00
Sanjay Patel d052de856d [DAGCombiner] restrict (float)((int) f) --> ftrunc with no-signed-zeros
As noted in the D44909 review, the transform from (fptosi+sitofp) to ftrunc 
can produce -0.0 where the original code does not:

#include <stdio.h>
  
int main(int argc) {
  float x;
  x = -0.8 * argc;
  printf("%f\n", (float)((int)x));
  return 0;
}

$ clang -O0 -mavx fp.c ; ./a.out 
0.000000
$ clang -O1 -mavx fp.c ; ./a.out 
-0.000000

Ideally, we'd use IR/node flags to predicate the transform, but the IR parser 
doesn't currently allow fast-math-flags on the cast instructions. So for now, 
just use the function attribute that corresponds to clang's "-fno-signed-zeros" 
option.

Differential Revision: https://reviews.llvm.org/D48085

llvm-svn: 335761
2018-06-27 18:16:40 +00:00
Simon Pilgrim d3e583a52d [DAGCombiner] visitSDIV - add special case handling for (sdiv X, 1) -> X in pow2 expansion
For divisor = 1, perform a select of X - reduces scalarisation of simple SDIVs

llvm-svn: 335727
2018-06-27 12:45:31 +00:00
Simon Pilgrim e835f662fa [DAGCombiner] visitSDIV - simplify pow2 handling. NFCI.
Use the builtin constant folding of getNode() etc. instead of doing it manually.

llvm-svn: 335720
2018-06-27 10:51:55 +00:00
Simon Pilgrim dfbcc66adc [DAGCombiner] Fold SDIV(%X, MIN_SIGNED) -> SELECT(%X == MIN_SIGNED, 1, 0)
Fixes PR37569.

llvm-svn: 335719
2018-06-27 10:21:06 +00:00
Simon Pilgrim 0a566bc0ae [DAGCombiner] Don't accept signbit sdiv divisors in sdiv-by-pow2 vector expansion (PR37569)
llvm-svn: 335717
2018-06-27 09:41:22 +00:00
Sanjay Patel fb9c440ba5 [DAGCombiner] use isBitwiseNot to simplify code; NFC
llvm-svn: 335652
2018-06-26 19:46:56 +00:00
Simon Pilgrim 7f55af37f4 [DAGCombiner] Don't accept -1 sdiv divisors in sdiv-by-pow2 vector expansion (PR37119)
Temporary fix until I've managed to get D45806 updated - both +1 and -1 special cases need to be properly supported.

llvm-svn: 335637
2018-06-26 17:46:51 +00:00
Simon Pilgrim 133b1cdf08 [DAGCombiner] Pull out VT bitwidth in visitSDIV. NFCI.
llvm-svn: 335617
2018-06-26 15:39:16 +00:00
Vedant Kumar b725c69f12 [SelectionDAG] Remove debug locations from ConstantSD(FP)Nodes
This removes debug locations from ConstantSDNode and ConstantSDFPNode.

When this kind of node is materialized we no longer create a line table
entry which jumps back to the constant's first point of use. This makes
single-stepping behavior smoother, and it matches the model used by IR,
where Constants have no locations. See this thread for more context:

  http://lists.llvm.org/pipermail/llvm-dev/2018-June/124164.html

I'd like to handle constant BuildVectorSDNodes and to try to eliminate
passing SDLocs to SelectionDAG::getConstant*() in follow-up commits.

Differential Revision: https://reviews.llvm.org/D48468

llvm-svn: 335497
2018-06-25 17:06:18 +00:00
Simon Pilgrim 5b6b500687 Fix -Wparentheses gcc warning. NFCI.
llvm-svn: 335451
2018-06-25 11:19:05 +00:00
Sanjay Patel 962ee178fa [DAGCombiner] eliminate setcc bool math when input is low-bit of some value
This patch has the same motivating example as D48466:
define void @foo(i64 %x, i32 %c.0282.in, i32 %d.0280, i32* %ptr0, i32* %ptr1) {
    %c.0282 = and i32 %c.0282.in, 268435455
    %a16 = lshr i64 32508, %x
    %a17 = and i64 %a16, 1
    %tobool = icmp eq i64 %a17, 0
    %. = select i1 %tobool, i32 1, i32 2
    %.286 = select i1 %tobool, i32 27, i32 26
    %shr97 = lshr i32 %c.0282, %.
    %shl98 = shl i32 %c.0282.in, %.286
    %or99 = or i32 %shr97, %shl98
    %shr100 = lshr i32 %d.0280, %.
    %shl101 = shl i32 %d.0280, %.286
    %or102 = or i32 %shr100, %shl101
    store i32 %or99, i32* %ptr0
    store i32 %or102, i32* %ptr1
    ret void
}

...but I'm trying to kill the setcc bool math sooner rather than later.

By matching a larger pattern that includes both the low-bit mask and the trailing add/sub, 
we can create a universally good fold because we always eliminate the condition code 
intermediate value.

Here are Alive proofs for these (currently instcombine folds the 'add' variants, but 
misses the 'sub' patterns):
https://rise4fun.com/Alive/Gsyp

Name: sub of zext cmp mask
  %a = and i8 %x, 1
  %c = icmp eq i8 %a, 0
  %z = zext i1 %c to i32
  %r = sub i32 C1, %z
  =>
  %optional_cast = zext i8 %a to i32
  %r = add i32 %optional_cast, C1-1

Name: add of zext cmp mask
  %a = and i32 %x, 1
  %c = icmp eq i32 %a, 0
  %z = zext i1 %c to i8
  %r = add i8 %z, C1
  =>
  %optional_cast = trunc i32 %a to i8
  %r = sub i8 C1+1, %optional_cast

All of the tests look like improvements or neutral to me. But it is possible that x86 
test+set+bitop is better than what we now show here. I suspect we could do better by 
adding another fold for the 'sub' variants.

We start with select-of-constant in IR in the larger motivating test, so that's why I 
included tests with selects. Proofs for those variants:
https://rise4fun.com/Alive/Bx1

Name: true const is bigger
Pre: C2 == (C1 + 1)
  %a = and i8 %x, 1
  %c = icmp eq i8 %a, 0
  %r = select i1 %c, i64 C2, i64 C1
  =>
  %z = zext i8 %a to i64
  %r = sub i64 C2, %z

Name: false const is bigger
Pre: C2 == (C1 + 1)
  %a = and i8 %x, 1
  %c = icmp eq i8 %a, 0
  %r = select i1 %c, i64 C1, i64 C2
  =>
  %z = zext i8 %a to i64
  %r = add i64 C1, %z

Differential Revision: https://reviews.llvm.org/D48466

llvm-svn: 335433
2018-06-24 14:37:30 +00:00
Stanislav Mekhanoshin 22ee191c3e DAG combine "and|or (select c, -1, 0), x" -> "select c, x, 0|-1"
Allowed folding for "and/or" binops with non-constant operand if
arguments of select are 0/-1 values.

Normally this code with "and" opcode does not get to a DAG combiner
and simplified yet in the InstCombine. However AMDGPU produces it
during lowering and InstCombine has no chance to optimize it out.

In turn the same pattern with "or" opcode can reach DAG.

Differential Revision: https://reviews.llvm.org/D48301

llvm-svn: 335250
2018-06-21 16:02:05 +00:00
Mikael Holmen 42f7bc96dd [DebugInfo] Make sure all DBG_VALUEs' reguse operands have IsDebug property
Summary:
In some cases, these operands lacked the IsDebug property, which is meant to signal that
they should not affect codegen. This patch adds a check for this property in the
MachineVerifier and adds it where it was missing.

This includes refactorings to use MachineInstrBuilder construction functions instead of
manually setting up the intrinsic everywhere.

Patch by: JesperAntonsson

Reviewers: aprantl, rnk, echristo, javed.absar

Reviewed By: aprantl

Subscribers: qcolombet, sdardis, nemanjai, JDevlieghere, atanasyan, llvm-commits

Differential Revision: https://reviews.llvm.org/D48319

llvm-svn: 335214
2018-06-21 10:03:34 +00:00
David Green a465188500 [DAGCombine] Fix alignment for offset loads/stores
The alignment parameter to getExtLoad is treated as a base alignment,
not the alignment of the load (base + offset). When we infer a better
alignment for a Ptr we need to ensure that it applies to the base to
prevent the alignment on the load from being wrong.

This fixes a bug where the alignment could then be used to incorrectly
prove noalias between a load and a store, leading to a miscompile.

Differential Revision: https://reviews.llvm.org/D48029

llvm-svn: 335210
2018-06-21 08:30:07 +00:00
Stanislav Mekhanoshin 20279dc025 Allow binop C1, (select cc, CF, CT) -> select folding
Previously this folding was done only if select is a first operand.
However, for non-commutative operations constant may go before
select.

Differential Revision: https://reviews.llvm.org/D48223

llvm-svn: 335167
2018-06-20 20:24:20 +00:00
Bjorn Pettersson 7bf676662a [DAG] Don't map a TableId to itself in the ReplacedValues map
Summary:
Found some regressions (infinite loop in DAGTypeLegalizer::RemapId)
after r334880. This patch makes sure that we do map a TableId to
itself.

Reviewers: niravd

Reviewed By: niravd

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D48364

llvm-svn: 335141
2018-06-20 16:06:09 +00:00
Nirav Dave cd558887d3 [DAG] Fix and-mask folding when narrowing loads.
Summary:
Check that and masks are strictly smaller than implicit mask from
narrowed load.

Fixes PR37820.

Reviewers: samparker, RKSimon, nemanjai

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D48335

llvm-svn: 335137
2018-06-20 15:36:29 +00:00
Craig Topper ddd88a559f [DAGCombiner] Add some comments to some true/false arguments to make it obvious what they are. NFC
llvm-svn: 335095
2018-06-20 04:32:07 +00:00
Craig Topper 59da74370b [SelectionDAG] Don't crash on inline assembly errors when the inline assembly return type is a struct.
Summary:
If we get an error building the SelectionDAG for inline assembly we try to continue and still build the DAG.

But if the return type for the inline assembly is a struct we end up crashing because we try to create an UNDEF node with a struct type which isn't valid.

Instead we need to create an UNDEF for each element of the struct and join them with merge_values.

This patch relies on single operand merge_values being handled gracefully by getMergeValues. If the return type is void there will be no VTs returned by ComputeValueVTs and now we just return instead of calling setValue. Hopefully that's ok, I assumed nothing would need to look up the mapped value for void node.

Fixes PR37359

Reviewers: rengolin, rovka, echristo, efriedma, bogner

Reviewed By: efriedma

Subscribers: craig.topper, llvm-commits

Differential Revision: https://reviews.llvm.org/D46560

llvm-svn: 335093
2018-06-20 04:32:05 +00:00
Heejin Ahn 33c3fce592 [WebAssembly] Add WasmEHFuncInfo for unwind destination information
Summary:
Add WasmEHFuncInfo and routines to calculate and fill in this struct to
keep track of unwind destination information. This will be used in
other EH related passes.

Reviewers: dschuff

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

Differential Revision: https://reviews.llvm.org/D48263

llvm-svn: 335005
2018-06-19 00:26:39 +00:00
Michael Berg 7b993d762f Utilize new SDNode flag functionality to expand current support for fadd
Summary: This patch originated from D46562 and is a proper subset, with some issues addressed.

Reviewers: spatel, hfinkel, wristow, arsenm, javed.absar

Reviewed By: spatel

Subscribers: wdng, nhaehnle

Differential Revision: https://reviews.llvm.org/D47909

llvm-svn: 334996
2018-06-18 23:44:59 +00:00
Michael Berg 932ba20af8 refactor of visitFADD for AllowNewConst cases
Summary: Refactoring for all constant cases which require AllowNewConst and some staging for future fmf usage.

Reviewers: spatel, hfinkel, wristow

Reviewed By: spatel

Subscribers: nhaehnle

Differential Revision: https://reviews.llvm.org/D48289

llvm-svn: 334984
2018-06-18 21:12:21 +00:00
Nirav Dave d4ff2f8a74 Avoid needing to walk out legalization tables. NFCI.
Relanding after fixing expensive check from modifying tables.

To avoid redundant work, during DAG legalization we keep tables
mapping pre-legalized SDValues to post-legalized SDValues and a
SDValue-to-SDValue map to enable fast node replacements. However, as
the keys are nodes which may be reused it is possible that an entry in
a table refers to a now deleted node N (that should have been renamed
by the value replacement map) while a new node N' exists. If N' is
then replaced that entry would be wrong. Previously we avoided this by
when potentially violating this property, walking every table and
updating all node pointers. This is very expensive but hopefully rare
occurance.

This patch assigns each instance of a SDValue used in legalization a
unique id and uses these ids in the legalization tables. This avoids
any such aliasing issue, avoiding the full table search and allowing
more aggressive incremental table pruning.

In some cases this is a 1000x speedup to compilation.

Reviewers: jyknight, echristo, bogner, tra

Reviewed By: bogner

Subscribers: dberris, grandinj, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D47959

llvm-svn: 334880
2018-06-16 02:51:29 +00:00
Michael Berg 8e570c3390 Utilize new SDNode flag functionality to expand current support for fma
Summary: This patch originated from D47388 and is a proper subset of the originating changes, containing only the fmf optimization guard extensions.

Reviewers: spatel, hfinkel, wristow, arsenm, javed.absar, rampitec, nhaehnle, nemanjai

Reviewed By: rampitec, nhaehnle

Subscribers: tpr, nemanjai, wdng

Differential Revision: https://reviews.llvm.org/D47918

llvm-svn: 334876
2018-06-16 00:03:06 +00:00
Francis Visoiu Mistrih dc705a6a89 Revert r334729 "[DAG] Avoid needing to walk out legalization tables. NFCI."
This reverts commit r334729.

llvm-svn: 334869
2018-06-15 23:05:41 +00:00
Francis Visoiu Mistrih 1c9df30eca Revert r334731 "Avoid unused variable in non-assert builds."
This reverts commit r334731.

It breaks EXPENSIVE_CHECKS bots.

llvm-svn: 334868
2018-06-15 23:05:40 +00:00
Cameron McInally 7caac670b2 [FPEnv] Expand constrained FP POWI
Modify ExpandStrictFPOp(...) to handle nodes that have scalar
operands. 

Also, add a Strict FMA test and do some other light cleanup in the
Strict FP code.

Differential Revision: https://reviews.llvm.org/D48149

llvm-svn: 334863
2018-06-15 20:57:55 +00:00
Michael Berg 02d1c6c0cf Utilize new SDNode flag functionality to expand current support for fdiv
Summary: This patch originated from D46562 and is a proper subset, with some issues addressed.

Reviewers: spatel, hfinkel, wristow, arsenm

Reviewed By: spatel

Subscribers: wdng, nhaehnle

Differential Revision: https://reviews.llvm.org/D47954

llvm-svn: 334862
2018-06-15 20:44:55 +00:00
Matt Arsenault df2f4ef29d DAG: Fix creating concat_vectors with illegal type
Test passes as is, but fails with future patch to make v4i16/v4f16
legal.

llvm-svn: 334823
2018-06-15 12:09:15 +00:00