diff --git a/lib/Analysis/ConstantFolding.cpp b/lib/Analysis/ConstantFolding.cpp
index 5bf5539f5c9..0a9d725db58 100644
--- a/lib/Analysis/ConstantFolding.cpp
+++ b/lib/Analysis/ConstantFolding.cpp
@@ -81,7 +81,7 @@ Constant *FoldBitCast(Constant *C, Type *DestTy, const DataLayout &DL) {
 
     // Now that we know that the input value is a vector of integers, just shift
     // and insert them into our result.
-    unsigned BitShift = DL.getTypeAllocSizeInBits(SrcEltTy);
+    unsigned BitShift = DL.getTypeSizeInBits(SrcEltTy);
     APInt Result(IT->getBitWidth(), 0);
     for (unsigned i = 0; i != NumSrcElts; ++i) {
       Constant *Element;
diff --git a/test/Transforms/InstCombine/bitcast.ll b/test/Transforms/InstCombine/bitcast.ll
index 254b6116e4c..74958596f23 100644
--- a/test/Transforms/InstCombine/bitcast.ll
+++ b/test/Transforms/InstCombine/bitcast.ll
@@ -262,3 +262,10 @@ define <2 x i64> @test7(<2 x i8*>* %arg) nounwind {
 ; CHECK: bitcast
 ; CHECK: load
 }
+
+define i8 @test8() {
+  %res = bitcast <8 x i1> <i1 true, i1 true, i1 false, i1 true, i1 false, i1 true, i1 false, i1 true> to i8
+  ret i8 %res
+; CHECK: @test8
+; CHECK: ret i8 -85
+}