Commit Graph

828 Commits

Author SHA1 Message Date
Simon Pilgrim f05369768c [TargetLowering] SimplifyDemandedBits - add ANY_EXTEND_VECTOR_INREG support
Move 'lowest' demanded elt -> bitcast fold out of ZERO_EXTEND_VECTOR_INREG into ANY_EXTEND_VECTOR_INREG case.

llvm-svn: 363856
2019-06-19 18:34:58 +00:00
Simon Pilgrim 6016fb726c [TargetLowering] SimplifyDemandedBits ZERO_EXTEND_VECTOR_INREG -> ANY_EXTEND_VECTOR_INREG
Simplify ZERO_EXTEND_VECTOR_INREG if the extended bits are not required.

Matches what we already do for ZERO_EXTEND.

llvm-svn: 363850
2019-06-19 18:00:24 +00:00
Simon Pilgrim c3994f77cb [TargetLowering] SimplifyDemandedBits SIGN_EXTEND_VECTOR_INREG -> ANY/ZERO_EXTEND_VECTOR_INREG
Simplify SIGN_EXTEND_VECTOR_INREG if the extended bits are not required/known zero.

Matches what we already do for SIGN_EXTEND.

llvm-svn: 363802
2019-06-19 13:58:02 +00:00
Simon Pilgrim 5bef886cd8 [TargetLowering] SimplifyDemandedBits - Cleanup ANY_EXTEND handling
Match SIGN_EXTEND + ZERO_EXTEND handling - will be adding ANY_EXTEND_VECTOR_INREG support in a future patch.

llvm-svn: 363716
2019-06-18 18:22:30 +00:00
Simon Pilgrim 032b54f8e8 [TargetLowering] SimplifyDemandedBits - Merge ZERO_EXTEND+ZERO_EXTEND_VECTOR_INREG handling
Other than adding consistent demanded elts handling which was a trivial addition, the other differences in functionality will be added in later patches.

llvm-svn: 363713
2019-06-18 18:08:30 +00:00
Simon Pilgrim b6e7108dcd [TargetLowering] SimplifyDemandedBits - Merge SIGN_EXTEND+SIGN_EXTEND_VECTOR_INREG handling
Other than adding consistent demanded elts handling which was a trivial addition, the other differences in functionality will be added in later patches.

llvm-svn: 363710
2019-06-18 17:57:53 +00:00
Simon Pilgrim 9aa25be149 [TargetLowering] SimplifyDemandedVectorElts - support MUL and ANY_EXTEND_VECTOR_INREG
Also fold ANY_EXTEND_VECTOR_INREG -> BITCAST if we only need the bottom element.

Fixes temporary regression introduced in rL363693.

llvm-svn: 363694
2019-06-18 15:49:35 +00:00
Simon Pilgrim 4e0648a541 [TargetLowering] Add MachineMemOperand::Flags to allowsMemoryAccess tests (PR42123)
As discussed on D62910, we need to check whether particular types of memory access are allowed, not just their alignment/address-space.

This NFC patch adds a MachineMemOperand::Flags argument to allowsMemoryAccess and allowsMisalignedMemoryAccesses, and wires up calls to pass the relevant flags to them.

If people are happy with this approach I can then update X86TargetLowering::allowsMisalignedMemoryAccesses to handle misaligned NT load/stores.

Differential Revision: https://reviews.llvm.org/D63075

llvm-svn: 363179
2019-06-12 17:14:03 +00:00
David Bolvansky dcf5e6abdf [TargetLowering] Simplify (ctpop x) == 1
Reviewers: craig.topper, spatel, RKSimon, bkramer

Reviewed By: spatel

Subscribers: javed.absar, lebedev.ri, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D63004

llvm-svn: 362912
2019-06-09 18:18:57 +00:00
Tim Northover 607c8a9d14 IR: make getParamByValType Just Work. NFC.
Most parts of LLVM don't care whether the byval type is derived from an
explicit Attribute or from the parameter's pointee type, so it makes
sense for the main access function to just return the right value.

The very few users who do care (only BitcodeReader so far) can find out
how it's specified by accessing the Attribute directly.

llvm-svn: 362642
2019-06-05 20:37:47 +00:00
Simon Pilgrim 5a81af547c [TargetLowering] SimplifyDemandedBits - pull out shift value type. NFCI.
Will be used more in an upcoming patch.

llvm-svn: 362595
2019-06-05 10:59:04 +00:00
Simon Pilgrim 88522ce388 [TargetLowering] SimplifyDemandedBits - don't use OriginalDemanded variables in analysis.
These might have been replaced in multiple use cases.

llvm-svn: 362322
2019-06-02 10:12:55 +00:00
Simon Pilgrim 30a6caa3e7 [TargetLowering] SimplifyDemandedVectorElts - use same arg names as SimplifyDemandedBits. NFCI.
Helps with debugging as we recurse between them.

llvm-svn: 362321
2019-06-02 10:03:56 +00:00
Tim Northover b7141207a4 Reapply: IR: add optional type to 'byval' function parameters
When we switch to opaque pointer types we will need some way to describe
how many bytes a 'byval' parameter should occupy on the stack. This adds
a (for now) optional extra type parameter.

If present, the type must match the pointee type of the argument.

The original commit did not remap byval types when linking modules, which broke
LTO. This version fixes that.

Note to front-end maintainers: if this causes test failures, it's probably
because the "byval" attribute is printed after attributes without any parameter
after this change.

llvm-svn: 362128
2019-05-30 18:48:23 +00:00
Tim Northover 71ee3d0237 Revert "IR: add optional type to 'byval' function parameters"
The IRLinker doesn't delve into the new byval attribute when mapping types, and
this breaks LTO.

llvm-svn: 362029
2019-05-29 20:46:38 +00:00
Tim Northover 6e07f16fae IR: add optional type to 'byval' function parameters
When we switch to opaque pointer types we will need some way to describe
how many bytes a 'byval' parameter should occupy on the stack. This adds
a (for now) optional extra type parameter.

If present, the type must match the pointee type of the argument.

Note to front-end maintainers: if this causes test failures, it's probably
because the "byval" attribute is printed after attributes without any parameter
after this change.

llvm-svn: 362012
2019-05-29 19:12:48 +00:00
Simon Pilgrim 95b8d9bbf8 [SelectionDAG] computeKnownBits - support constant pool values from target
This patch adds the overridable TargetLowering::getTargetConstantFromLoad function which allows targets to return any constant value loaded by a LoadSDNode node - only X86 makes use of this so far but everything should be in place for other targets.

computeKnownBits then uses this function to improve codegen, notably vector code after legalization.

A future commit will do the same for ComputeNumSignBits but computeKnownBits sees the bigger benefit.

This required a couple of fixes:
* SimplifyDemandedBits must early-out for getTargetConstantFromLoad cases to prevent infinite loops of constant regeneration (similar to what we already do for BUILD_VECTOR).
* Fix a DAGCombiner::visitTRUNCATE issue as we had trunc(shl(v8i32),v8i16) <-> shl(trunc(v8i16),v8i32) infinite loops after legalization on AVX512 targets.

Differential Revision: https://reviews.llvm.org/D61887

llvm-svn: 361620
2019-05-24 10:03:11 +00:00
Kees Cook c2187c20a4 [TargetLowering] Extend bool args to inline-asm according to getBooleanType
Summary:
This extends Krzysztof Parzyszek's X86-specific solution
(https://reviews.llvm.org/D60208) to the generic code pointed out by
James Y Knight.

Reviewers: kparzysz, craig.topper, nickdesaulniers

Subscribers: efriedma, sdardis, nemanjai, javed.absar, eraman, fedor.sergeev, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, jsji, llvm-commits, srhines, void, nickdesaulniers, jyknight

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60224

llvm-svn: 361404
2019-05-22 16:16:15 +00:00
Kees Cook a7a687e500 [TargetLowering] Add blank line (test commit)
llvm-svn: 361403
2019-05-22 16:02:13 +00:00
Leonard Chan 0bada7ce6c [Intrinsic] Signed Fixed Point Saturation 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. The
result is saturated and clamped between the largest and smallest representable
values of the first 2 operands.

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/D55720

llvm-svn: 361289
2019-05-21 19:17:19 +00:00
Dylan McKay e967308da4 Add TargetLoweringInfo hook for explicitly setting the ABI calling convention endianess
Summary:
The endianess used in the calling convention does not always match the
endianess of the target on all architectures, namely AVR.

When an argument is too large to be legalised by the architecture and is
split for the ABI, a new hook TargetLoweringInfo::shouldSplitFunctionArgumentsAsLittleEndian
is queried to find the endianess that function arguments must be laid
out in.

This approach was recommended by Eli Friedman.

Originally reported in https://github.com/avr-rust/rust/issues/129.

Patch by Carl Peto.

Reviewers: bogner, t.p.northover, RKSimon, niravd, efriedma

Reviewed By: efriedma

Subscribers: JDevlieghere, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D62003

llvm-svn: 361222
2019-05-21 06:38:02 +00:00
Nikita Popov 9060b6df97 [SDAG] Vector op legalization for overflow ops
Fixes issue reported by aemerson on D57348. Vector op legalization
support is added for uaddo, usubo, saddo and ssubo (umulo and smulo
were already supported). As usual, by extracting TargetLowering methods
and calling them from vector op legalization.

Vector op legalization doesn't really deal with multiple result nodes,
so I'm explicitly performing a recursive legalization call on the
result value that is not being legalized.

There are some existing test changes because expansion happens
earlier, so we don't get a DAG combiner run in between anymore.

Differential Revision: https://reviews.llvm.org/D61692

llvm-svn: 361166
2019-05-20 16:09:22 +00:00
Sanjay Patel 99d6420a82 [SDAG] fix unused variable warning and unneeded indirection; NFC
llvm-svn: 360640
2019-05-14 00:57:31 +00:00
Sanjay Patel 3a13d970aa [SDAG, x86] allow targets to override test for binop opcodes
This follows the pattern of the existing isCommutativeBinOp().

x86 shows improvements from vector narrowing for the min/max opcodes.

llvm-svn: 360639
2019-05-14 00:39:40 +00:00
Nick Desaulniers c33f754e74 [TargetLowering] Handle multi depth GEPs w/ inline asm constraints
Summary:
X86TargetLowering::LowerAsmOperandForConstraint had better support than
TargetLowering::LowerAsmOperandForConstraint for arbitrary depth
getelementpointers for "i", "n", and "s" extended inline assembly
constraints. Hoist its support from the derived class into the base
class.

Link: https://github.com/ClangBuiltLinux/linux/issues/469

Reviewers: echristo, t.p.northover

Reviewed By: t.p.northover

Subscribers: t.p.northover, E5ten, kees, jyknight, nemanjai, javed.absar, eraman, hiraditya, jsji, llvm-commits, void, craig.topper, nathanchance, srhines

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D61560

llvm-svn: 360604
2019-05-13 17:27:44 +00:00
Simon Pilgrim d3cedee3c6 [TargetLowering] Add SimplifyDemandedBits support for ZERO_EXTEND_VECTOR_INREG
More work for PR39709.

llvm-svn: 360592
2019-05-13 15:51:26 +00:00
Simon Pilgrim d845bc3d0c TargetLowering::SimplifyDemandedBits - early-out for UNDEF ops. NFCI.
llvm-svn: 360579
2019-05-13 12:44:03 +00:00
Craig Topper 61e556d2bd Recommit r358887 "[TargetLowering][AMDGPU][X86] Improve SimplifyDemandedBits bitcast handling"
I've included a new fix in X86RegisterInfo to prevent PR41619 without
reintroducing r359392. We might be able to improve that in the base class
implementation of shouldRewriteCopySrc somehow. But this hopefully enables
forward progress on SimplifyDemandedBits improvements for now.

Original commit message:

This patch adds support for BigBitWidth -> SmallBitWidth bitcasts, splitting the DemandedBits/Elts accordingly.

The AMDGPU backend needed an extra  (srl (and x, c1 << c2), c2) -> (and (srl(x, c2), c1) combine to encourage BFE creation, I investigated putting this in DAGComb
but it caused a lot of noise on other targets - some improvements, some regressions.

The X86 changes are all definite wins.

llvm-svn: 360552
2019-05-13 04:03:35 +00:00
Simon Pilgrim 605a840747 [DAG] Add SimplifyDemandedBits support for BITREVERSE
Pulled out of D58017 while I continue to investigate the BSWAP regression on PPC

llvm-svn: 360534
2019-05-11 20:56:05 +00:00
Craig Topper 55a71b575c Revert r359392 and r358887
Reverts "[X86] Remove (V)MOV64toSDrr/m and (V)MOVDI2SSrr/m. Use 128-bit result MOVD/MOVQ and COPY_TO_REGCLASS instead"
Reverts "[TargetLowering][AMDGPU][X86] Improve SimplifyDemandedBits bitcast handling"

Eric Christopher and Jorge Gorbe Moya reported some issues with these patches to me off list.

Removing the CodeGenOnly instructions has changed how fneg is handled during fast-isel with sse/sse2. We're now emitting fsub -0.0, x instead
moving to the integer domain(in a GPR), xoring the sign bit, and then moving back to xmm. This is because the fast isel table no longer
contains an entry for (f32/f64 bitcast (i32/i64)) so the target independent fneg code fails. The use of fsub changes the behavior of nan with
respect to -O2 codegen which will always use a pxor. NOTE: We still have a difference with double with -m32 since the move to GPR doesn't work
there. I'll file a separate PR for that and add test cases.

Since removing the CodeGenOnly instructions was fixing PR41619, I'm reverting r358887 which exposed that PR. Though I wouldn't be surprised
if that bug can still be hit independent of that.

This should hopefully get Google back to green. I'll work with Simon and other X86 folks to figure out how to move forward again.

llvm-svn: 360066
2019-05-06 19:29:24 +00:00
Simon Pilgrim 308b5ec1ff [TargetLowering] SimplifySetCC - remove repeated variable. NFCI.
Also reduce scope of Temp variable.

llvm-svn: 359911
2019-05-03 18:02:33 +00:00
Simon Pilgrim bc876df3a5 [TargetLowering] ShrinkDemandedConstant - reduce scope of TLO.DAG variable. NFCI.
Only ever used in one block

llvm-svn: 359890
2019-05-03 14:38:24 +00:00
Simon Pilgrim e798e3a346 [TargetLowering] expandUnalignedStore - cleanup EVT variables. NFCI.
Avoid duplicated EVTs and rename Store/Load VTs to avoid -Wshadow warnings.

llvm-svn: 359877
2019-05-03 12:55:25 +00:00
Sjoerd Meijer 0ed4619679 [TargetLowering] findOptimalMemOpLowering. NFCI.
This was a local static funtion in SelectionDAG, which I've promoted to
TargetLowering so that I can reuse it to estimate the cost of a memory
operation in D59787.

Differential Revision: https://reviews.llvm.org/D59766

llvm-svn: 359543
2019-04-30 10:09:15 +00:00
Simon Pilgrim 6276ce0142 [TargetLowering][AMDGPU][X86] Improve SimplifyDemandedBits bitcast handling
This patch adds support for BigBitWidth -> SmallBitWidth bitcasts, splitting the DemandedBits/Elts accordingly.

The AMDGPU backend needed an extra  (srl (and x, c1 << c2), c2) -> (and (srl(x, c2), c1) combine to encourage BFE creation, I investigated putting this in DAGCombine but it caused a lot of noise on other targets - some improvements, some regressions.

The X86 changes are all definite wins.

Differential Revision: https://reviews.llvm.org/D60462

llvm-svn: 358887
2019-04-22 14:04:35 +00:00
Craig Topper 3b1239d2a8 [TargetLowering][X86] Teach SimplifyDemandedBits to use ShrinkDemandedOp on ISD::SHL nodes.
If the upper bits of the SHL result aren't used, we might be able to use a narrower shift. For example, on X86 this can turn a 64-bit into 32-bit enabling a smaller encoding.

Differential Revision: https://reviews.llvm.org/D60358

llvm-svn: 358257
2019-04-12 06:49:28 +00:00
Simon Pilgrim d7cc0ec581 [TargetLowering] SimplifyDemandedBits - add ISD::INSERT_SUBVECTOR support
llvm-svn: 358019
2019-04-09 16:52:21 +00:00
Simon Pilgrim 55f79ef9fe [TargetLowering] SimplifyDemandedBits - Remove GetDemandedSrcMask lambda. NFCI.
An older version of this could return false but now that this always succeeds we can just inline and simplify it.

llvm-svn: 357999
2019-04-09 12:29:26 +00:00
Simon Pilgrim 345eacd555 [TargetLowering] SimplifyDemandedBits - call SimplifyDemandedBits in bitcast handling
When bitcasting from a source op to a larger bitwidth op, split the demanded bits and OR them on top of one another and demand those merged bits in the SimplifyDemandedBits call on the source op.

llvm-svn: 357992
2019-04-09 10:27:59 +00:00
Simon Pilgrim 9f74df7d5b [TargetLowering] SimplifyDemandedBits - use DemandedElts in bitcast handling
Be more selective in the SimplifyDemandedBits -> SimplifyDemandedVectorElts bitcast call based on the demanded elts.

llvm-svn: 357942
2019-04-08 20:59:38 +00:00
Simon Pilgrim 561ba38623 [DAG] Pull out ComputeNumSignBits call to make debugging easier. NFCI.
llvm-svn: 357861
2019-04-07 11:49:33 +00:00
Simon Pilgrim e24441aab0 [TargetLowering] Add SimplifyDemandedBits support for ISD::INSERT_VECTOR_ELT
This helps us relax the extension of a lot of scalar elements before they are inserted into a vector.

Its exposes an issue in DAGCombiner::convertBuildVecZextToZext as some/all the zero-extensions may be relaxed to ANY_EXTEND, so we need to handle that case to avoid a couple of AVX2 VPMOVZX test regressions.

Once this is in it should be easier to fix a number of remaining failures to fold loads into VBROADCAST nodes.

Differential Revision: https://reviews.llvm.org/D59484

llvm-svn: 356989
2019-03-26 12:32:01 +00:00
Simon Pilgrim 94e8f152c1 [TargetLowering] SimplifyDemandedBits trunc(srl(x, C1)) - early out for out of range C1. NFCI.
llvm-svn: 356810
2019-03-22 20:53:49 +00:00
Sanjay Patel 6a6e808b69 [TargetLowering] improve the default expansion of uaddsat/usubsat
This is a subset of what was proposed in:
D59006
...and may overlap with test changes from:
D59174
...but it seems like a good general optimization to turn selects
into bitwise-logic when possible because we never know exactly
what can happen at this stage of DAG combining depending on how
the target has defined things.

Differential Revision: https://reviews.llvm.org/D59066

llvm-svn: 356332
2019-03-17 14:57:40 +00:00
Simon Pilgrim 8fbe439345 [SelectionDAG] Add SimplifyDemandedBits handling for ISD::SCALAR_TO_VECTOR
Fixes a lot of constant folding mismatches between i686 and x86_64

llvm-svn: 356273
2019-03-15 17:00:55 +00:00
Simon Pilgrim 360ce82db2 [DAG] Move integer setcc %x, %x folding into FoldSetCC
First step towards PR40800 - I intend to move the float case in a separate future patch.

I had to tweak the (overly reduced) thumb2 test and the x86 widening test change is annoying (no longer rematerializable) but we should address this separately.

Differential Revision: https://reviews.llvm.org/D59244

llvm-svn: 356040
2019-03-13 11:08:57 +00:00
Nikita Popov 149bc099f6 [SDAG] Expand pow2 mulo using shifts
Expand MULO with constant power of two operand into a shift. The
overflow is checked with (x << shift) >> shift == x, where the right
shift will be logical for umulo and arithmetic for smulo (with
exception for multiplications by signed_min).

Differential Revision: https://reviews.llvm.org/D59041

llvm-svn: 355937
2019-03-12 16:57:25 +00:00
Nikita Popov aa7cfa75f9 [SDAG][AArch64] Legalize VECREDUCE
Fixes https://bugs.llvm.org/show_bug.cgi?id=36796.

Implement basic legalizations (PromoteIntRes, PromoteIntOp,
ExpandIntRes, ScalarizeVecOp, WidenVecOp) for VECREDUCE opcodes.
There are more legalizations missing (esp float legalizations),
but there's no way to test them right now, so I'm not adding them.

This also includes a few more changes to make this work somewhat
reasonably:

 * Add support for expanding VECREDUCE in SDAG. Usually
   experimental.vector.reduce is expanded prior to codegen, but if the
   target does have native vector reduce, it may of course still be
   necessary to expand due to legalization issues. This uses a shuffle
   reduction if possible, followed by a naive scalar reduction.
 * Allow the result type of integer VECREDUCE to be larger than the
   vector element type. For example we need to be able to reduce a v8i8
   into an (nominally) i32 result type on AArch64.
 * Use the vector operand type rather than the scalar result type to
   determine the action, so we can control exactly which vector types are
   supported. Also change the legalize vector op code to handle
   operations that only have vector operands, but no vector results, as
   is the case for VECREDUCE.
 * Default VECREDUCE to Expand. On AArch64 (only target using VECREDUCE),
   explicitly specify for which vector types the reductions are supported.

This does not handle anything related to VECREDUCE_STRICT_*.

Differential Revision: https://reviews.llvm.org/D58015

llvm-svn: 355860
2019-03-11 20:22:13 +00:00
Simon Pilgrim 1bb5b56485 [DAG] Move SetCC NaN handling into FoldSetCC
llvm-svn: 355845
2019-03-11 17:43:10 +00:00
Simon Pilgrim 53518b45a5 [DAG] TargetLowering::SimplifySetCC - call FoldSetCC early to handle constant/commute folds.
Noticed while looking at PR40800 (and also D57921)

llvm-svn: 355828
2019-03-11 15:01:31 +00:00