Commit Graph

29326 Commits

Author SHA1 Message Date
Craig Topper 844e94a502 [SelectionDAGBuilder] Remove Unnecessary FastMathFlags temporary. Use SDNodeFlags instead. NFCI
This was a missed simplication in D87200
2020-09-08 15:50:12 -07:00
Craig Topper b1e68f885b [SelectionDAGBuilder] Pass fast math flags to getNode calls rather than trying to set them after the fact.:
This removes the after the fact FMF handling from D46854 in favor of passing fast math flags to getNode. This should be a superset of D87130.

This required adding a SDNodeFlags to SelectionDAG::getSetCC.

Now we manage to contant fold some stuff undefs during the
initial getNode that we don't do in later DAG combines.

Differential Revision: https://reviews.llvm.org/D87200
2020-09-08 15:27:21 -07:00
Volkan Keles 1242dd330d GlobalISel: Combine `op undef, x` to 0
https://reviews.llvm.org/D86611
2020-09-08 09:46:38 -07:00
Simon Pilgrim 3c83b967cf LiveRegUnits.h - reduce MachineRegisterInfo.h include. NFC.
We only need to include MachineInstrBundle.h, but exposes an implicit dependency in MachineOutliner.h.

Also, remove duplicate includes from LiveRegUnits.cpp + MachineOutliner.cpp.
2020-09-08 17:27:00 +01:00
Jonas Paulsson 6dc3e22b57 [DAGTypeLegalizer] Handle ZERO_EXTEND of promoted type in WidenVecRes_Convert.
On SystemZ, a ZERO_EXTEND of an i1 vector handled by WidenVecRes_Convert()
always ended up being scalarized, because the type action of the input is
promotion which was previously an unhandled case in this method.

This fixes https://bugs.llvm.org/show_bug.cgi?id=47132.

Differential Revision: https://reviews.llvm.org/D86268

Patch by Eli Friedman.
Review: Ulrich Weigand
2020-09-08 16:49:51 +02:00
Craig Topper da79b1eecc [SelectionDAG][X86][ARM] Teach ExpandIntRes_ABS to use sra+add+xor expansion when ADDCARRY is supported.
Rather than using SELECT instructions, use SRA, UADDO/ADDCARRY and
XORs to expand ABS. This is the multi-part version of the sequence
we use in LegalizeDAG.

It's also the same as the Custom sequence uses for i64 on 32-bit
and i128 on 64-bit. So we can remove the X86 customization.

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D87215
2020-09-07 13:15:26 -07:00
Sanjay Patel 7a06b166b1 [DAGCombiner] allow more store merging for non-i8 truncated ops
This is a follow-up suggested in D86420 - if we have a pair of stores
in inverted order for the target endian, we can rotate the source
bits into place.
The "be_i64_to_i16_order" test shows a limitation of the current
function (which might be avoided if we integrate this function with
the other cases in mergeConsecutiveStores). In the earlier
"be_i64_to_i16" test, we skip the first 2 stores because we do not
match the full set as consecutive or rotate-able, but then we reach
the last 2 stores and see that they are an inverted pair of 16-bit
stores. The "be_i64_to_i16_order" test alters the program order of
the stores, so we miss matching the sub-pattern.

Differential Revision: https://reviews.llvm.org/D87112
2020-09-07 14:12:36 -04:00
Momchil Velikov eb482afaf5 Reduce the number of memory allocations when displaying
a warning about clobbering reserved registers (NFC).

Also address some minor inefficiencies and style issues.

Differential Revision: https://reviews.llvm.org/D86088
2020-09-07 17:04:00 +01:00
Simon Pilgrim 6670f5d1e6 MachineStableHash.h - remove MachineInstr.h include. NFC.
Use forward declarations and move the include to MachineStableHash.cpp
2020-09-07 13:33:48 +01:00
Simon Wallis 79ea83e104 [SelectionDAG] memcpy expansion of const volatile struct ignores const zero
In getMemcpyLoadsAndStores(), a memcpy where the source is a zero constant is expanded to a MemOp::Set instead of a MemOp::Copy, even when the memcpy is volatile.
This is incorrect.

The fix is to add a check for volatile, and expand to MemOp::Copy in the volatile case.

Reviewed By: chill

Differential Revision: https://reviews.llvm.org/D87134
2020-09-07 13:22:09 +01:00
Simon Pilgrim e57cbcbdc1 LegalizeTypes.h - remove orphan SplitVSETCC declaration. NFCI.
The implementation no longer exists
2020-09-07 13:11:49 +01:00
Jay Foad 713c2ad60c [GlobalISel] Extend not_cmp_fold to work on conditional expressions
Differential Revision: https://reviews.llvm.org/D86709
2020-09-07 09:31:08 +01:00
Jay Foad 5350e1b509 [KnownBits] Implement accurate unsigned and signed max and min
Use the new implementation in ValueTracking, SelectionDAG and
GlobalISel.

Differential Revision: https://reviews.llvm.org/D87034
2020-09-07 09:09:01 +01:00
Amara Emerson d0abc75749 [GlobalISel] Disable the indexed loads combine completely unless forced. NFC.
The post-index matcher, before it queries the target legality, walks uses
of some instructions which in pathological cases can be massive. Since
no targets actually support indexed loads yet, disable this to stop wasting
compile time on something which is going to fail anyway.
2020-09-05 21:04:03 -07:00
Jonas Paulsson 714ceefad9 [SelectionDAG] Always intersect SDNode flags during getNode() node memoization.
Previously SDNodeFlags::instersectWith(Flags) would do nothing if Flags was
in an undefined state, which is very bad given that this is the default when
getNode() is called without passing an explicit SDNodeFlags argument.

This meant that if an already existing and reused node had a flag which the
second caller to getNode() did not set, that flag would remain uncleared.

This was exposed by https://bugs.llvm.org/show_bug.cgi?id=47092, where an NSW
flag was incorrectly set on an add instruction (which did in fact overflow in
one of the two original contexts), so when SystemZElimCompare removed the
compare with 0 trusting that flag, wrong-code resulted.

There is more that needs to be done in this area as discussed here:

Differential Revision: https://reviews.llvm.org/D86871

Review: Ulrich Weigand, Sanjay Patel
2020-09-05 10:30:38 +02:00
Fangrui Song 398ba37230 [LiveDebugVariables] Delete unneeded doInitialization 2020-09-04 13:27:42 -07:00
Simon Pilgrim 7582c5c023 CallingConvLower.h - remove unnecessary MachineFunction.h include. NFC.
Reduce to forward declaration, add the Register.h include that we still needed, move CCState::ensureMaxAlignment into CallingConvLower.cpp as it was the only function that needed the full definition of MachineFunction.

Fix a few implicit dependencies further down.
2020-09-04 12:16:48 +01:00
David Sherwood 73a3d350a4 [SVE][CodeGen] Fix up warnings in sve-split-insert/extract tests
I have fixed up some more ElementCount/TypeSize related warnings in
the following tests:

  CodeGen/AArch64/sve-split-extract-elt.ll
  CodeGen/AArch64/sve-split-insert-elt.ll

In SelectionDAG::CreateStackTemporary we were relying upon the implicit
cast from TypeSize -> uint64_t when calling MachineFrameInfo::CreateStackObject.
I've fixed this by passing in the known minimum size instead, which I
believe is fine because the associated stack id indicates whether this
is a scalable object or not.

I've also fixed up a case in TargetLowering::SimplifyDemandedBits when
extracting a vector element from a scalable vector. The result is a scalar,
hence it wasn't caught at the start of the function. If the vector is
scalable we just bail out for now.

Differential Revision: https://reviews.llvm.org/D86431
2020-09-04 09:51:31 +01:00
Michael Liao bf41c4d29e [codegen] Ensure target flags are cleared/set properly. NFC.
- When an operand is changed into an immediate value or like, ensure their
  target flags being cleared or set properly.

Differential Revision: https://reviews.llvm.org/D87109
2020-09-03 18:37:39 -04:00
Puyan Lotfi 7fff1fbd3c [MIRVRegNamer] Experimental MachineInstr stable hashing (Fowler-Noll-Vo)
This hashing scheme has been useful out of tree, and I want to start
experimenting with it. Specifically I want to experiment on the
MIRVRegNamer, MIRCanononicalizer, and eventually the MachineOutliner.

This diff is a first step, that optionally brings stable hashing to the
MIRVRegNamer (and as a result, the MIRCanonicalizer).  We've tested this
hashing scheme on a lot of MachineOperand types that llvm::hash_value
can not handle in a stable manner.

This stable hashing was also the basis for

"Global Machine Outliner for ThinLTO" in EuroLLVM 2020

http://llvm.org/devmtg/2020-04/talks.html#TechTalk_58

Credits: Kyungwoo Lee, Nikolai Tillmann

Differential Revision: https://reviews.llvm.org/D86952
2020-09-03 16:13:09 -04:00
Amy Huang 5fe33f7399 [DebugInfo] Make DWARF ignore sizes on forward declared class types.
Make sure the sizes for forward declared classes aren't emitted in
DWARF.

This comes before https://reviews.llvm.org/D87062, which adds sizes to
all classes with definitions.

Bug: https://bugs.llvm.org/show_bug.cgi?id=47338

Differential Revision: https://reviews.llvm.org/D87070
2020-09-03 11:01:49 -07:00
Simon Pilgrim 1673a08044 SelectionDAG.h - remove unnecessary FunctionLoweringInfo.h include. NFCI.
Use forward declarations and move the include down to dependent files that actually use it.

This also exposes a number of implicit dependencies on KnownBits.h
2020-09-03 18:33:25 +01:00
Simon Pilgrim 46780cc0ee PHIEliminationUtils.cpp - remove unnecessary MachineBasicBlock.h include. NFCI.
This is already included in PHIEliminationUtils.h
2020-09-03 17:43:34 +01:00
Simon Pilgrim 6731eb644a Fix Wdocumentation trailing comments warnings. NFCI. 2020-09-03 17:43:34 +01:00
Simon Pilgrim b196c7192f Fix Wdocumentation warning. NFCI.
Remove \returns tag from a void function
2020-09-03 17:43:34 +01:00
Simon Pilgrim 898e42db93 GlobalISel/Utils.h - remove unused includes. NFCI.
Twine is unused, and TargetLowering can be reduced to a forward declaration and moved to Utils.cpp
2020-09-03 15:59:12 +01:00
Simon Pilgrim 91848b11b4 LowerEmuTLS.cpp - remove unused TargetLowering.h include. NFC.
We only needed llvm/IR/Constants.h.
2020-09-03 14:40:09 +01:00
Amara Emerson 2878ecc90f [StackProtector] Fix crash with vararg due to not checking LocationSize validity.
Differential Revision: https://reviews.llvm.org/D87074
2020-09-03 00:08:48 -07:00
Craig Topper b16e8687ab [CodeGenPrepare][X86] Teach optimizeGatherScatterInst to turn a splat pointer into GEP with scalar base and 0 index
This helps SelectionDAGBuilder recognize the splat can be used as a uniform base.

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D86371
2020-09-02 20:44:12 -07:00
Jay Foad 099c089d4b [APInt] New member function setBitVal
Differential Revision: https://reviews.llvm.org/D87033
2020-09-02 21:40:31 +01:00
Anna Thomas 425573a2fa [ImplicitNullChecks] NFC: Refactor dependence safety check
After computing dependence, we check if it is safe to hoist by
identifying if it clobbers any liveIns in the sibling block (NullSucc).
This check is moved to its own function which will be used in the
soon-to-be modified dependence checking algorithm for implicit null
checks pass.

Tests-Run: lit tests on X86/implicit-*
2020-09-02 10:29:44 -04:00
Anna Thomas 6f7737c468 [ImplicitNullChecks] NFC: Separated out checks and added comments
Separated out some checks in isSuitableMemoryOp and added comments
explaining why some of those checks are done.

Tests-Run:X86 implicit null checks tests.
2020-09-02 10:29:44 -04:00
Paul Walker f72121254d [SVE] Don't reorder subvector/binop sequences when the resulting binop is not legal.
When lowering fixed length vector operations for SVE the subvector
operations are used extensively to marshall data between scalable
and fixed-length vectors. This means that sequences like:

  extract_subvec(binop(insert_subvec(a), insert_subvec(b)))

are very common. DAGCombine only checks if the resulting binop is
legal or can be custom lowered when undoing such sequences. When
it's custom lowering that is introducing them the result is an
infinite legalise->combine->legalise loop.

This patch extends the isOperationLegalOr... functions to include
a "LegalOnly" parameter to restrict the check to legal operations
only. Although isOperationLegal could be used it's common for
the affected code paths to be visited pre and post legalisation,
so the extra parameter keeps the code tidy.

Differential Revision: https://reviews.llvm.org/D86450
2020-09-02 11:01:33 +01:00
Sander de Smalen f13beac51b [AArch64][SVE] Preserve full vector regs over EH edge.
Unwinders may only preserve the lower 64bits of Neon and SVE registers,
as only the registers in the base ABI are guaranteed to be preserved
over the exception edge. The caller will need to preserve additional
registers for when the call throws an exception and the unwinder has
tried to recover state.

For  e.g.

    svint32_t bar(svint32_t);
    svint32_t foo(svint32_t x, bool *err) {
      try { bar(x); } catch (...) { *err = true; }
      return x;
    }

`z0` needs to be spilled before the call to `bar(x)` and reloaded before
returning from foo, as the exception handler may have clobbered z0.

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D84737
2020-09-02 10:54:18 +01:00
Igor Kudrin 3445ec9ba7 [DebugInfo] Emit a 1-byte value as a terminator of entries list in the name index.
As stated in section 6.1.1.2, DWARFv5, p. 142,
| The last entry for each name is followed by a zero byte that
| terminates the list. There may be gaps between the lists.

The patch changes emitting a 4-byte zero value to a 1-byte one, which
effectively removes the gap between entry lists, and thus saves
approximately 3 bytes per name; the calculation is not exact because
the total size of the table is aligned to 4.

Differential Revision: https://reviews.llvm.org/D86927
2020-09-02 16:12:39 +07:00
Igor Kudrin 71eed4808f [DebugInfo] Remove Dwarf5AccelTableWriter::Header::UnitLength. NFC.
The member is not in use; the unit length for the table is emitted as
a difference between two labels. Moreover, the type of the member might
be misleading, because for DWARF64 the field should be 64 bit long.

Differential Revision: https://reviews.llvm.org/D86912
2020-09-02 16:11:45 +07:00
Cameron McInally cfe2b81710 [SVE] Update INSERT_SUBVECTOR DAGCombine to use getVectorElementCount().
A small piece of the project to replace getVectorNumElements() with getVectorElementCount().

Differential Revision: https://reviews.llvm.org/D86894
2020-09-01 16:51:44 -05:00
Amara Emerson 520ab710fb Revert "Revert "[GlobalISel] Fold xor(cmp(pred, _, _), 1) -> cmp(inverse(pred), _, _)" (and dependent patch "Optimize away a Not feeding a brcond by using tbz instead of tbnz.")"
This reverts commit 8693ddc743.

Re-committing with the test requiring asserts.
2020-09-01 14:29:04 -07:00
Jordan Rupprecht 8693ddc743 Revert "[GlobalISel] Fold xor(cmp(pred, _, _), 1) -> cmp(inverse(pred), _, _)" (and dependent patch "Optimize away a Not feeding a brcond by using tbz instead of tbnz.")
This reverts commit 8ad8f484b6. It causes crashes when running `ninja check-llvm-codegen-aarch64-globalisel`, e.g.
http://lab.llvm.org:8011/builders/clang-with-thin-lto-ubuntu/builds/24132/steps/test-stage1-compiler/logs/stdio.
Note that the crash does not seem to reproduce in debug builds.

5ded444252 depends on this, so revert that too.
2020-09-01 13:31:57 -07:00
Craig Topper 4783e2c9c6 [MachineCopyPropagation] In isNopCopy, check the destination registers match in addition to the source registers.
Previously if the source match we asserted that the destination
matched. But GPR <-> mask register copies on X86 can violate this
since we use the same K-registers for multiple sizes.

Fixes this ISPC issue https://github.com/ispc/ispc/issues/1851

Differential Revision: https://reviews.llvm.org/D86507
2020-09-01 12:44:32 -07:00
Amara Emerson 8ad8f484b6 [GlobalISel] Fold xor(cmp(pred, _, _), 1) -> cmp(inverse(pred), _, _)
This is needed for an upcoming change to how we translate conditional branches
which might generate these.

Differential Revision: https://reviews.llvm.org/D86383
2020-09-01 10:57:17 -07:00
Matt Arsenault 32a8a10b42 GlobalISel: Implement computeNumSignBits for G_SELECT 2020-09-01 12:50:19 -04:00
Matt Arsenault 35c94d3f7e GlobalISel: Port smarter known bits for umin/umax from DAG 2020-09-01 12:50:15 -04:00
Matt Arsenault 759482ddaa GlobalISel: Implement computeKnownBits for G_BSWAP and G_BITREVERSE 2020-09-01 12:49:57 -04:00
Sam Tebbs 15e880a04f [DAGCombiner] Fold an AND of a masked load into a zext_masked_load
This patch folds an AND of a masked load and build vector into a zero
extended masked load.

Differential Revision: https://reviews.llvm.org/D86789
2020-09-01 17:02:07 +01:00
Volkan Keles 061182b7ba GlobalISel: Add combines for extend operations
https://reviews.llvm.org/D86516
2020-09-01 08:50:06 -07:00
Matt Arsenault 9e7e1b2d4b GlobalISel: Implement computeNumSignBits for G_SEXTLOAD/G_ZEXTLOAD 2020-09-01 11:20:02 -04:00
Matt Arsenault 92090e8bd8 GlobalISel: Implement computeKnownBits for G_UNMERGE_VALUES 2020-09-01 11:19:27 -04:00
Sourabh Singh Tomar 03812041d8 [NFCI] Removed an un-used declaration got accidentally introduced in f91d18eaa9 2020-09-01 15:59:04 +05:30
David Sherwood 9fbb113247 [SVE][CodeGen] Fix TypeSize/ElementCount related warnings in sve-split-load.ll
I have fixed up a number of warnings resulting from TypeSize -> uint64_t
casts and calling getVectorNumElements() on scalable vector types. I
think most of the changes are fairly trivial except for those in
DAGTypeLegalizer::SplitVecRes_MLOAD I've tried to ensure we create
the MachineMemoryOperands in a sensible way for scalable vectors.

I have added a CHECK line to the following test:

  CodeGen/AArch64/sve-split-load.ll

that ensures no new warnings are added.

Differential Revision: https://reviews.llvm.org/D86697
2020-09-01 07:47:59 +01:00