757 Commits

Author SHA1 Message Date
Leonard Chan
ae527ac603 [Intrinsic] Expand SMULFIX to MUL, MULH[US], or [US]MUL_LOHI on vector arguments
r zero scale SMULFIX, expand into MUL which produces better code for X86.

For vector arguments, expand into MUL if SMULFIX is provided with a zero scale.
Otherwise, expand into MULH[US] or [US]MUL_LOHI.

Differential Revision: https://reviews.llvm.org/D56987

llvm-svn: 352783
2019-01-31 19:15:37 +00:00
James Y Knight
5d71fc5d7b Adjust documentation for git migration.
This fixes most references to the paths:
 llvm.org/svn/
 llvm.org/git/
 llvm.org/viewvc/
 github.com/llvm-mirror/
 github.com/llvm-project/
 reviews.llvm.org/diffusion/

to instead point to https://github.com/llvm/llvm-project.

This is *not* a trivial substitution, because additionally, all the
checkout instructions had to be migrated to instruct users on how to
use the monorepo layout, setting LLVM_ENABLE_PROJECTS instead of
checking out various projects into various subdirectories.

I've attempted to not change any scripts here, only documentation. The
scripts will have to be addressed separately.

Additionally, I've deleted one document which appeared to be outdated
and unneeded:
  lldb/docs/building-with-debug-llvm.txt

Differential Revision: https://reviews.llvm.org/D57330

llvm-svn: 352514
2019-01-29 16:37:27 +00:00
Nikita Popov
8e1a464e6a [CodeGen][X86] Expand UADDSAT to NOT+UMIN+ADD
Followup to D56636, this time handling the UADDSAT case by expanding
uadd.sat(a, b) to umin(a, ~b) + b.

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

llvm-svn: 352409
2019-01-28 19:19:09 +00:00
Simon Pilgrim
2f018de6a3 [TargetLowering] Rename getExpandedFixedPointMultiplication to expandFixedPointMul. NFCI.
Match the (much shorter) name used in various legalization methods.

llvm-svn: 352056
2019-01-24 15:46:54 +00:00
Chandler Carruth
2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

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

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

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
Nikita Popov
d3b86b79fa Reapply "[CodeGen][X86] Expand USUBSAT to UMAX+SUB, also for vectors"
Related to https://bugs.llvm.org/show_bug.cgi?id=40123.

Rather than scalarizing, expand a vector USUBSAT into UMAX+SUB,
which produces much better code for X86.

Reapplying with updated SLPVectorizer tests.

Differential Revision: https://reviews.llvm.org/D56636

llvm-svn: 351219
2019-01-15 18:43:41 +00:00
Nikita Popov
5885eec35a Revert "[CodeGen][X86] Expand USUBSAT to UMAX+SUB, also for vectors"
This reverts commit r351125.

I missed test changes in an SLPVectorizer test, due to the cost model
changes. Reverting for now.

llvm-svn: 351129
2019-01-14 22:18:39 +00:00
Nikita Popov
8e9a8432a8 [CodeGen][X86] Expand USUBSAT to UMAX+SUB, also for vectors
Related to https://bugs.llvm.org/show_bug.cgi?id=40123.

Rather than scalarizing, expand a vector USUBSAT into UMAX+SUB,
which produces much better code for X86.

Differential Revision: https://reviews.llvm.org/D56636

llvm-svn: 351125
2019-01-14 21:43:30 +00:00
Nikita Popov
0400e50445 [X86] Rename overly verbose method; NFC
As suggested on D56636.

llvm-svn: 351021
2019-01-13 16:41:26 +00:00
Simon Pilgrim
0d92c4debc Use getShiftAmountTy for shift amounts.
llvm-svn: 351005
2019-01-12 12:00:43 +00:00
Simon Pilgrim
ca0de0363b [X86][AARCH64] Improve ISD::ABS support
This patch takes some of the code from D49837 to allow us to enable ISD::ABS support for all SSE vector types.

Differential Revision: https://reviews.llvm.org/D56544

llvm-svn: 350998
2019-01-12 09:59:32 +00:00
Stanislav Mekhanoshin
ed0d6c60af Remove check for single use in ShrinkDemandedConstant
This removes check for single use from general ShrinkDemandedConstant
to the BE because of the AArch64 regression after D56289/rL350475.

After several hours of experiments I did not come up with a testcase
failing on any other targets if check is not performed.

Moreover, direct call to ShrinkDemandedConstant is not really needed
and superceed by SimplifyDemandedBits.

Differential Revision: https://reviews.llvm.org/D56406

llvm-svn: 350684
2019-01-09 02:24:22 +00:00
Craig Topper
826f44b550 [TargetLowering][AMDGPU] Remove the SimplifyDemandedBits function that takes a User and OpIdx. Stop using it in AMDGPU target for simplifyI24.
As we saw in D56057 when we tried to use this function on X86, it's unsafe. It allows the operand node to have multiple users, but doesn't prevent recursing past the first node when it does have multiple users. This can cause other simplifications earlier in the graph without regard to what bits are needed by the other users of the first node. Ideally all we should do to the first node if it has multiple uses is bypass it when its not needed by the user we started from. Doing any other transformation that SimplifyDemandedBits can do like turning ZEXT/SEXT into AEXT would result in an increase in instructions.

Fortunately, we already have a function that can do just that, GetDemandedBits. It will only make transformations that involve bypassing a node.

This patch changes AMDGPU's simplifyI24, to use a combination of GetDemandedBits to handle the multiple use simplifications. And then uses the regular SimplifyDemandedBits on each operand to handle simplifications allowed when the operand only has a single use. Unfortunately, GetDemandedBits simplifies constants more aggressively than SimplifyDemandedBits. This caused the -7 constant in the changed test to be simplified to remove the upper bits. I had to modify computeKnownBits to account for this by ignoring the upper 8 bits of the input.

Differential Revision: https://reviews.llvm.org/D56087

llvm-svn: 350560
2019-01-07 19:30:43 +00:00
Stanislav Mekhanoshin
35a3a3bd11 Added single use check to ShrinkDemandedConstant
Fixes cvt_f32_ubyte combine. performCvtF32UByteNCombine() could shrink
source node to demanded bits only even if there are other uses.

Differential Revision: https://reviews.llvm.org/D56289

llvm-svn: 350475
2019-01-05 19:20:00 +00:00
Simon Pilgrim
911dce2f30 [SelectionDAG] Always use the version of computeKnownBits that returns a value. NFCI.
Continues the work started by @bogner in rL340594 to remove uses of the KnownBits output paramater version.

llvm-svn: 349907
2018-12-21 14:56:18 +00:00
Simon Pilgrim
6c95bea072 [TargetLowering] Fix propagation of undefs in zero extension ops (PR40091)
As described on PR40091, we have several places where zext (and zext_vector_inreg) fold an undef input into an undef output. For zero extensions this is incorrect as the output should guarantee to least have the new upper bits set to zero.

SimplifyDemandedVectorElts is the worst offender (and its the most likely to cause new undefs to appear) but DAGCombiner's tryToFoldExtendOfConstant has a similar issue.

Thanks to @dmgreen for catching this.

Differential Revision: https://reviews.llvm.org/D55883

llvm-svn: 349625
2018-12-19 13:37:59 +00:00
Simon Pilgrim
af6fbbf18b [TargetLowering] Fallback from SimplifyDemandedVectorElts to SimplifyDemandedBits
For opcodes not covered by SimplifyDemandedVectorElts, SimplifyDemandedBits might be able to help now that it supports demanded elts as well.

llvm-svn: 349466
2018-12-18 09:33:25 +00:00
JF Bastien
1811217e4d NFC: remove unused variable
D55768 removed its use.

llvm-svn: 349377
2018-12-17 19:03:24 +00:00
Simon Pilgrim
9274f17a5e [TargetLowering] Add DemandedElts mask to SimplifyDemandedBits (PR40000)
This is an initial patch to add the necessary support for a DemandedElts argument to SimplifyDemandedBits, more closely matching computeKnownBits and to help improve vector codegen.

I've added only a small amount of the changes necessary to get at least one test to update - a lot more can be done but I'd like to add these methodically with proper test coverage, at the same time the hope is to slowly move some/all of SimplifyDemandedVectorElts into SimplifyDemandedBits as well.

Differential Revision: https://reviews.llvm.org/D55768

llvm-svn: 349374
2018-12-17 18:43:43 +00:00
Simon Pilgrim
1e1fd9c761 [TargetLowering] Add ISD::OR + ISD::XOR handling to SimplifyDemandedVectorElts
Differential Revision: https://reviews.llvm.org/D55600

llvm-svn: 349264
2018-12-15 11:36:36 +00:00
Simon Pilgrim
77fc551d1a [TargetLowering] Add ISD::ROTL/ROTR vector expansion
Move existing rotation expansion code into TargetLowering and set it up for vectors as well.

Ideally this would share more of the funnel shift expansion, but we handle the shift amount modulo quite differently at the moment.

Begun removing x86 vector rotate custom lowering to use the expansion.

llvm-svn: 349025
2018-12-13 11:20:48 +00:00
Simon Pilgrim
f6c898e12f [TargetLowering] Add ISD::AND handling to SimplifyDemandedVectorElts
If either of the operand elements are zero then we know the result element is going to be zero (even if the other element is undef).

Differential Revision: https://reviews.llvm.org/D55558

llvm-svn: 348926
2018-12-12 13:43:07 +00:00
Leonard Chan
118e53fd63 [Intrinsic] Signed Fixed Point Multiplication Intrinsic
Add an intrinsic that takes 2 signed integers with the scale of them provided
as the third argument and performs fixed point multiplication 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/D54719

llvm-svn: 348912
2018-12-12 06:29:14 +00:00
Simon Pilgrim
f6371f5f23 [TargetLowering] Add ISD::EXTRACT_VECTOR_ELT support to SimplifyDemandedBits
Let SimplifyDemandedBits attempt to simplify all elements of a vector extraction.

Part of PR39689.

llvm-svn: 348839
2018-12-11 11:08:40 +00:00
Simon Pilgrim
fc2c9af99c [TargetLowering] Add UNDEF folding to SimplifyDemandedVectorElts
If all the demanded elements of the SimplifyDemandedVectorElts are known to be UNDEF, we can simplify to an ISD::UNDEF node.

Zero constant folding will be handled in a future patch - its a little trickier as we often have bitcasted zero values.

Differential Revision: https://reviews.llvm.org/D55511

llvm-svn: 348784
2018-12-10 18:29:46 +00:00
Simon Pilgrim
8fdaf5c915 [TargetLowering] Remove ISD::ANY_EXTEND/ANY_EXTEND_VECTOR_INREG opcodes from SimplifyDemandedVectorElts
These have no test coverage and the KnownZero flags can't be guaranteed unlike SIGN/ZERO_EXTEND cases.

llvm-svn: 348361
2018-12-05 12:20:05 +00:00
Simon Pilgrim
180639afe5 [SelectionDAG] Initial support for FSHL/FSHR funnel shift opcodes (PR39467)
This is an initial patch to add a minimum level of support for funnel shifts to the SelectionDAG and to begin wiring it up to the X86 SHLD/SHRD instructions.

Some partial legalization code has been added to handle the case for 'SlowSHLD' where we want to expand instead and I've added a few DAG combines so we don't get regressions from the existing DAG builder expansion code.

Differential Revision: https://reviews.llvm.org/D54698

llvm-svn: 348353
2018-12-05 11:12:12 +00:00
Simon Pilgrim
d24730cdda [TargetLowering] SimplifyDemandedVectorElts - don't alter DemandedElts mask
Fix potential issue with the ISD::INSERT_VECTOR_ELT case tweaking the DemandedElts mask instead of using a local copy - so later uses of the mask use the tweaked version.....

Noticed while investigating adding zero/undef folding to SimplifyDemandedVectorElts and the altered DemandedElts mask was causing mismatches.

llvm-svn: 348348
2018-12-05 10:37:45 +00:00
Nirav Dave
ce26c27b2a [SelectionDAG] Redefine isGAPlusOffset in terms of unwrapAddress. NFCI.
llvm-svn: 348288
2018-12-04 17:59:43 +00:00
Simon Pilgrim
0add090e24 [TargetLowering] expandFP_TO_UINT - avoid FPE due to out of range conversion (PR17686)
PR17686 demonstrates that for some targets FP exceptions can fire in cases where the FP_TO_UINT is expanded using a FP_TO_SINT instruction.

The existing code converts both the inrange and outofrange cases using FP_TO_SINT and then selects the result, this patch changes this for 'strict' cases to pre-select the FP_TO_SINT input and the offset adjustment.

The X87 cases don't need the strict flag but generates much nicer code with it....

Differential Revision: https://reviews.llvm.org/D53794

llvm-svn: 348251
2018-12-04 11:21:30 +00:00
Simon Pilgrim
666261cdc8 [TargetLowering] Add SimplifyDemandedVectorElts support to EXTEND opcodes
Add support for ISD::*_EXTEND and ISD::*_EXTEND_VECTOR_INREG opcodes.

The extra broadcast in trunc-subvector.ll will be fixed in an upcoming patch.

llvm-svn: 348246
2018-12-04 10:41:06 +00:00
Simon Pilgrim
e017ed3245 [SelectionDAG] Improve SimplifyDemandedBits to SimplifyDemandedVectorElts simplification
D52935 introduced the ability for SimplifyDemandedBits to call SimplifyDemandedVectorElts through BITCASTs if the demanded bit mask entirely covered the sub element.

This patch relaxes this to demanding an element if we need any bit from it.

Differential Revision: https://reviews.llvm.org/D54761

llvm-svn: 348073
2018-12-01 12:08:55 +00:00
Simon Pilgrim
5448339889 [TargetLowering] SimplifyDemandedBits - only reduce known bits for integer constants
Avoids fuzzing crash found by Mikael Holmén.

llvm-svn: 347393
2018-11-21 14:26:19 +00:00
Simon Pilgrim
3735105961 [DAGCombine] Add calls to SimplifyDemandedVectorElts from visitINSERT_SUBVECTOR (PR37989)
This uncovered an off-by-one typo in SimplifyDemandedVectorElts's INSERT_SUBVECTOR handling as its bounds check was bailing on safe indices.

llvm-svn: 347313
2018-11-20 15:23:50 +00:00
Simon Pilgrim
b356d0463e [TargetLowering] Improve SimplifyDemandedVectorElts/SimplifyDemandedBits support
For bitcast nodes from larger element types, add the ability for SimplifyDemandedVectorElts to call SimplifyDemandedBits by merging the elts mask to a bits mask.

I've raised https://bugs.llvm.org/show_bug.cgi?id=39689 to deal with the few places where SimplifyDemandedBits's lack of vector handling is a problem.

Differential Revision: https://reviews.llvm.org/D54679

llvm-svn: 347301
2018-11-20 12:02:16 +00:00
Simon Pilgrim
de3605f56b [TargetLowering] expandFP_TO_UINT - improve fp16 support
As discussed on D53794, for float types with ranges smaller than the destination integer type, then we should be able to just use a regular FP_TO_SINT opcode.

I thought we'd need to provide MSA test cases for very small integer types as well (fp16 -> i8 etc.), but it turns out that promotion will kick in so they're unnecessary.

Differential Revision: https://reviews.llvm.org/D54703

llvm-svn: 347251
2018-11-19 19:16:13 +00:00
Simon Pilgrim
3c8baf4f90 [TargetLowering] Cleanup more of the EXTEND demanded bits cases so that they match. NFCI.
Use the same variable names etc.

llvm-svn: 347045
2018-11-16 12:26:26 +00:00
Simon Pilgrim
6bd468bd8b [TargetLowering] Begin generalizing TargetLowering::expandFP_TO_SINT support. NFCI.
Prior to initial work to add vector expansion support, remove assumptions that we're working on scalar types.

llvm-svn: 346139
2018-11-05 15:49:09 +00:00
Simon Pilgrim
b34a052852 [LegalizeDAG] Add generic vector CTPOP expansion (PR32655)
This patch adds support for expanding vector CTPOP instructions and removes the x86 'bitmath' lowering which replicates the same expansion.

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

llvm-svn: 345869
2018-11-01 18:22:11 +00:00
Stanislav Mekhanoshin
222e9c11f7 Check shouldReduceLoadWidth from SimplifySetCC
SimplifySetCC could shrink a load without checking for
profitability or legality of such shink with a target.

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

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

llvm-svn: 345778
2018-10-31 21:24:30 +00:00
Leonard Chan
905abe5b5d [Intrinsic] Signed and Unsigned Saturation Subtraction Intirnsics
Add an intrinsic that takes 2 integers and perform saturation subtraction on
them.

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

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

llvm-svn: 345512
2018-10-29 16:54:37 +00:00
Simon Pilgrim
3497d536f7 [TargetLowering] Move i64/vXi64 to f32/vXf32 UINT_TO_FP handling to TargetLowering::expandUINT_TO_FP.
llvm-svn: 345478
2018-10-28 15:34:35 +00:00
Simon Pilgrim
9b77f0c291 [VectorLegalizer] Enable TargetLowering::expandFP_TO_UINT support.
Add vector support to TargetLowering::expandFP_TO_UINT.

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

llvm-svn: 345473
2018-10-28 13:07:25 +00:00
Simon Pilgrim
3cf33fcdd6 [TargetLowering] Move LegalizeDAG FP_TO_UINT handling to TargetLowering::expandFP_TO_UINT. NFCI.
First step towards fixing PR17686 and adding vector support.

llvm-svn: 345452
2018-10-27 12:15:58 +00:00
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
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
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
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