add another case of undefined behavior without crashing, PR3466.

llvm-svn: 63620

2 files changed, 12 insertions, 2 deletions

diff --git a/llvm/lib/Transforms/Scalar/ScalarReplAggregates.cpp b/llvm/lib/Transforms/Scalar/ScalarReplAggregates.cpp
index 83572d65dae..c67c67a4b62 100644
--- a/llvm/lib/Transforms/Scalar/ScalarReplAggregates.cpp
+++ b/llvm/lib/Transforms/Scalar/ScalarReplAggregates.cpp
@@ -1431,8 +1431,9 @@ Value *SROA::ConvertUsesOfLoadToScalar(LoadInst *LI, AllocaInst *NewAI,
   // Finally, unconditionally truncate the integer to the right width.
   unsigned LIBitWidth = TD->getTypeSizeInBits(LI->getType());
   if (LIBitWidth < NTy->getBitWidth())
-    NV = new TruncInst(NV, IntegerType::get(LIBitWidth),
-                       LI->getName(), LI);
+    NV = new TruncInst(NV, IntegerType::get(LIBitWidth), LI->getName(), LI);
+  else if (LIBitWidth > NTy->getBitWidth())
+    NV = new ZExtInst(NV, IntegerType::get(LIBitWidth), LI->getName(), LI);
 
   // If the result is an integer, this is a trunc or bitcast.
   if (isa<IntegerType>(LI->getType())) {
diff --git a/llvm/test/Transforms/ScalarRepl/badarray.ll b/llvm/test/Transforms/ScalarRepl/badarray.ll
index acac5a61822..c4884863056 100644
--- a/llvm/test/Transforms/ScalarRepl/badarray.ll
+++ b/llvm/test/Transforms/ScalarRepl/badarray.ll
@@ -1,4 +1,5 @@
 ; RUN: llvm-as < %s | opt -scalarrepl -instcombine | llvm-dis | not grep alloca
+; PR3466
 
 define i32 @test() {
 	%X = alloca [4 x i32]		; <[4 x i32]*> [#uses=1]
@@ -9,3 +10,11 @@ define i32 @test() {
 	ret i32 %Z
 }
 
+
+define i32 @test2() nounwind {
+entry:
+        %yx2.i = alloca float, align 4          ; <float*> [#uses=1]            
+        %yx26.i = bitcast float* %yx2.i to i64*         ; <i64*> [#uses=1]      
+        %0 = load i64* %yx26.i, align 8         ; <i64> [#uses=0]               
+        unreachable
+}