[InstCombine] Don't coerce non-integral pointers to integers

Reviewers: majnemer

Subscribers: mcrosier, llvm-commits

Differential Revision: https://reviews.llvm.org/D23231

llvm-svn: 277910

3 files changed, 35 insertions, 1 deletions

diff --git a/llvm/include/llvm/IR/DataLayout.h b/llvm/include/llvm/IR/DataLayout.h
index 2b481fb6607..e309e93a14e 100644
--- a/llvm/include/llvm/IR/DataLayout.h
+++ b/llvm/include/llvm/IR/DataLayout.h
@@ -338,6 +338,11 @@ public:
            NonIntegralSpaces.end();
   }
 
+  bool isNonIntegralPointerType(Type *Ty) const {
+    auto *PTy = dyn_cast<PointerType>(Ty);
+    return PTy && isNonIntegralPointerType(PTy);
+  }
+
   /// Layout pointer size, in bits
   /// FIXME: The defaults need to be removed once all of
   /// the backends/clients are updated.
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp b/llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
index 736c95adae1..8dcc6351ac7 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
@@ -475,7 +475,8 @@ static Instruction *combineLoadToOperationType(InstCombiner &IC, LoadInst &LI) {
   // size is a legal integer type.
   if (!Ty->isIntegerTy() && Ty->isSized() &&
       DL.isLegalInteger(DL.getTypeStoreSizeInBits(Ty)) &&
-      DL.getTypeStoreSizeInBits(Ty) == DL.getTypeSizeInBits(Ty)) {
+      DL.getTypeStoreSizeInBits(Ty) == DL.getTypeSizeInBits(Ty) &&
+      !DL.isNonIntegralPointerType(Ty)) {
     if (std::all_of(LI.user_begin(), LI.user_end(), [&LI](User *U) {
           auto *SI = dyn_cast<StoreInst>(U);
           return SI && SI->getPointerOperand() != &LI;
diff --git a/llvm/test/Transforms/InstCombine/non-integral-pointers.ll b/llvm/test/Transforms/InstCombine/non-integral-pointers.ll
index d5e2569179b..4f54fe6737d 100644
--- a/llvm/test/Transforms/InstCombine/non-integral-pointers.ll
+++ b/llvm/test/Transforms/InstCombine/non-integral-pointers.ll
@@ -18,3 +18,31 @@ define i8 addrspace(3)* @f_1() {
   %result = getelementptr i8, i8 addrspace(3)* null, i64 50
   ret i8 addrspace(3)* %result
 }
+
+define void @f_2(i8 addrspace(4)** %ptr0, i8 addrspace(4)** %ptr1) {
+; It is not okay to convert the load/store pair to load and store
+; integers, since pointers in address space 4 are non-integral.
+
+; CHECK-LABEL: @f_2(
+entry:
+; CHECK:  %val = load i8 addrspace(4)*, i8 addrspace(4)** %ptr0, align 8
+; CHECK:  store i8 addrspace(4)* %val, i8 addrspace(4)** %ptr1, align 8
+; CHECK-NOT: load i64
+; CHECK-NOT: store i64
+  %val = load i8 addrspace(4)*, i8 addrspace(4)** %ptr0
+  store i8 addrspace(4)* %val, i8 addrspace(4)** %ptr1
+  ret void
+}
+
+define void @f_3(i8 addrspace(3)** %ptr0, i8 addrspace(3)** %ptr1) {
+; It *is* okay to convert the load/store pair to load and store
+; integers, since pointers in address space 3 are integral.
+
+; CHECK-LABEL: @f_3(
+entry:
+; CHECK: load i64
+; CHECK:  store i64
+  %val = load i8 addrspace(3)*, i8 addrspace(3)** %ptr0
+  store i8 addrspace(3)* %val, i8 addrspace(3)** %ptr1
+  ret void
+}