Commit Graph

9181 Commits

Author SHA1 Message Date
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