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Differential D64928

[LAA] Re-check bit-width of pointers after stripping.
ClosedPublic

Authored by hliao on Jul 18 2019, 9:05 AM.

Details

Reviewers
jdoerfert
Commits
rG17a8a9277c11: [LAA] Re-check bit-width of pointers after stripping.
rL366470: [LAA] Re-check bit-width of pointers after stripping.
Summary
  • As the pointer stripping now tracks through addrspacecast, prepare to handle the bit-width difference from the result pointer.

Diff Detail

Event Timeline

hliao created this revision.Jul 18 2019, 9:05 AM
Herald added a project: Restricted Project. · View Herald TranscriptJul 18 2019, 9:05 AM
Herald added subscribers: llvm-commits, arphaman, hiraditya and 2 others. · View Herald Transcript
hliao added a comment.Jul 18 2019, 9:05 AM

a similar case to https://reviews.llvm.org/D64768

Harbormaster completed remote builds in B35272: Diff 210593.Jul 18 2019, 9:06 AM
jdoerfert accepted this revision.Jul 18 2019, 10:17 AM

LGTM.

This revision is now accepted and ready to land.Jul 18 2019, 10:17 AM
Closed by commit rL366470: [LAA] Re-check bit-width of pointers after stripping. (authored by hliao). · Explain WhyJul 18 2019, 10:32 AM
This revision was automatically updated to reflect the committed changes.

Revision Contents

PathSize
llvm/
lib/
Analysis/
15 lines
test/
Transforms/
SLPVectorizer/
AMDGPU/
13 lines

Diff 210593

llvm/lib/Analysis/LoopAccessAnalysis.cpp

Show First 20 Lines • Show All 1,183 Lines • ▼ Show 20 Lines if (PtrA == PtrB)
return false; return false;
// Make sure that A and B have the same type if required. // Make sure that A and B have the same type if required.
if (CheckType && PtrA->getType() != PtrB->getType()) if (CheckType && PtrA->getType() != PtrB->getType())
return false; return false;
unsigned IdxWidth = DL.getIndexSizeInBits(ASA); unsigned IdxWidth = DL.getIndexSizeInBits(ASA);
Type *Ty = cast<PointerType>(PtrA->getType())->getElementType(); Type *Ty = cast<PointerType>(PtrA->getType())->getElementType();
APInt Size(IdxWidth, DL.getTypeStoreSize(Ty));
APInt OffsetA(IdxWidth, 0), OffsetB(IdxWidth, 0); APInt OffsetA(IdxWidth, 0), OffsetB(IdxWidth, 0);
PtrA = PtrA->stripAndAccumulateInBoundsConstantOffsets(DL, OffsetA); PtrA = PtrA->stripAndAccumulateInBoundsConstantOffsets(DL, OffsetA);
PtrB = PtrB->stripAndAccumulateInBoundsConstantOffsets(DL, OffsetB); PtrB = PtrB->stripAndAccumulateInBoundsConstantOffsets(DL, OffsetB);
// Retrieve the address space again as pointer stripping now tracks through
// `addrspacecast`.
ASA = cast<PointerType>(PtrA->getType())->getAddressSpace();
ASB = cast<PointerType>(PtrB->getType())->getAddressSpace();
// Check that the address spaces match and that the pointers are valid.
if (ASA != ASB)
return false;
IdxWidth = DL.getIndexSizeInBits(ASA);
OffsetA = OffsetA.sextOrTrunc(IdxWidth);
OffsetB = OffsetB.sextOrTrunc(IdxWidth);
APInt Size(IdxWidth, DL.getTypeStoreSize(Ty));
// OffsetDelta = OffsetB - OffsetA; // OffsetDelta = OffsetB - OffsetA;
const SCEV *OffsetSCEVA = SE.getConstant(OffsetA); const SCEV *OffsetSCEVA = SE.getConstant(OffsetA);
const SCEV *OffsetSCEVB = SE.getConstant(OffsetB); const SCEV *OffsetSCEVB = SE.getConstant(OffsetB);
const SCEV *OffsetDeltaSCEV = SE.getMinusSCEV(OffsetSCEVB, OffsetSCEVA); const SCEV *OffsetDeltaSCEV = SE.getMinusSCEV(OffsetSCEVB, OffsetSCEVA);
const SCEVConstant *OffsetDeltaC = dyn_cast<SCEVConstant>(OffsetDeltaSCEV); const SCEVConstant *OffsetDeltaC = dyn_cast<SCEVConstant>(OffsetDeltaSCEV);
const APInt &OffsetDelta = OffsetDeltaC->getAPInt(); const APInt &OffsetDelta = OffsetDeltaC->getAPInt();
// Check if they are based on the same pointer. That makes the offsets // Check if they are based on the same pointer. That makes the offsets
// sufficient. // sufficient.
▲ Show 20 Lines • Show All 1,238 Lines • Show Last 20 Lines

llvm/test/Transforms/SLPVectorizer/AMDGPU/address-space-ptr-sze-gep-index-assert.ll

Show First 20 Lines • Show All 141 Lines • ▼ Show 20 Linesbb:
%sub0 = sub i32 %load.flat.0, %load.lds.0 %sub0 = sub i32 %load.flat.0, %load.lds.0
%sub1 = sub i32 %load.flat.1, %load.lds.1 %sub1 = sub i32 %load.flat.1, %load.lds.1
store i32 %sub0, i32* undef store i32 %sub0, i32* undef
store i32 %sub1, i32* undef store i32 %sub1, i32* undef
ret void ret void
} }
; CHECK-LABEL: slp_crash_on_addrspacecast
; CHECK: ret void
define void @slp_crash_on_addrspacecast() {
entry:
%0 = getelementptr inbounds i64, i64 addrspace(3)* undef, i32 undef
%p0 = addrspacecast i64 addrspace(3)* %0 to i64*
store i64 undef, i64* %p0, align 8
%1 = getelementptr inbounds i64, i64 addrspace(3)* undef, i32 undef
%p1 = addrspacecast i64 addrspace(3)* %1 to i64*
store i64 undef, i64* %p1, align 8
ret void
}