[LoadStoreVectorizer] Differentiate between <1 x T> and T

[svenvh]

Summary

The LoadStoreVectorizer thought that <1 x T> and T were the same types
when merging stores, leading to a crash later.

Patch by Erik Hogeman.

[arsenm]

test/Transforms/LoadStoreVectorizer/X86/vector-scalar.ll

6

Use positive checks instead

[svenvh]

Updated test to use positive checks.

[arsenm]

LGTM

lib/Transforms/Vectorize/LoadStoreVectorizer.cpp

bool Vectorizer::isConsecutiveAccess(Value *A, Value *B) {
   if (!PtrA || !PtrB || (ASA != ASB))
     return false;
 
   // Make sure that A and B are different pointers of the same size type.
   unsigned PtrBitWidth = DL.getPointerSizeInBits(ASA);
   Type *PtrATy = PtrA->getType()->getPointerElementType();
   Type *PtrBTy = PtrB->getType()->getPointerElementType();
   if (PtrA == PtrB ||
+      PtrATy->isVectorTy() != PtrBTy->isVectorTy() ||
       DL.getTypeStoreSize(PtrATy) != DL.getTypeStoreSize(PtrBTy) ||
       DL.getTypeStoreSize(PtrATy->getScalarType()) !=
           DL.getTypeStoreSize(PtrBTy->getScalarType()))
     return false;
 
   APInt Size(PtrBitWidth, DL.getTypeStoreSize(PtrATy));
 
   unsigned IdxWidth = DL.getIndexSizeInBits(ASA);

test/Transforms/LoadStoreVectorizer/X86/vector-scalar.ll

+; RUN: opt -mtriple=x86_64-unknown-linux-gnu -load-store-vectorizer -mcpu haswell -S -o - %s | FileCheck %s
+
+; Check that the LoadStoreVectorizer does not crash due to not differentiating <1 x T> and T.
+
+; CHECK-LABEL: @vector_scalar(
+; CHECK-NOT: store <2 x double>
+define void @vector_scalar(double* %ptr, double %a, <1 x double> %b) {
+  %1 = bitcast double* %ptr to <1 x double>*
+  %2 = getelementptr <1 x double>, <1 x double>* %1, i32 1
+  store double %a, double* %ptr, align 8
+  store <1 x double> %b, <1 x double>* %2, align 8
+  ret void
+}