[PATCH] D64928: [LAA] Re-check bit-width of pointers after stripping.

[Michael Liao via Phabricator via llvm-commits]

hliao created this revision.
hliao added a reviewer: jdoerfert.
Herald added subscribers: llvm-commits, arphaman, hiraditya, nhaehnle, jvesely.
Herald added a project: LLVM.
hliao added a comment.

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


- As the pointer stripping now tracks through `addrspacecast`, prepare to handle the bit-width difference from the result pointer.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D64928

Files:
  llvm/lib/Analysis/LoopAccessAnalysis.cpp
  llvm/test/Transforms/SLPVectorizer/AMDGPU/address-space-ptr-sze-gep-index-assert.ll


Index: llvm/test/Transforms/SLPVectorizer/AMDGPU/address-space-ptr-sze-gep-index-assert.ll
===================================================================
--- llvm/test/Transforms/SLPVectorizer/AMDGPU/address-space-ptr-sze-gep-index-assert.ll
+++ llvm/test/Transforms/SLPVectorizer/AMDGPU/address-space-ptr-sze-gep-index-assert.ll
@@ -147,3 +147,16 @@
   store i32 %sub1, i32* undef
   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
+}
Index: llvm/lib/Analysis/LoopAccessAnalysis.cpp
===================================================================
--- llvm/lib/Analysis/LoopAccessAnalysis.cpp
+++ llvm/lib/Analysis/LoopAccessAnalysis.cpp
@@ -1189,12 +1189,25 @@
 
   unsigned IdxWidth = DL.getIndexSizeInBits(ASA);
   Type *Ty = cast<PointerType>(PtrA->getType())->getElementType();
-  APInt Size(IdxWidth, DL.getTypeStoreSize(Ty));
 
   APInt OffsetA(IdxWidth, 0), OffsetB(IdxWidth, 0);
   PtrA = PtrA->stripAndAccumulateInBoundsConstantOffsets(DL, OffsetA);
   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;
   const SCEV *OffsetSCEVA = SE.getConstant(OffsetA);
   const SCEV *OffsetSCEVB = SE.getConstant(OffsetB);


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D64928.210593.patch
Type: text/x-patch
Size: 2135 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20190718/e3677928/attachment.bin>