diff --git a/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp b/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp
--- a/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp
+++ b/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp
@@ -2107,7 +2107,7 @@
     // x86_64 can't use {float, float} since that would be returned in both
     // xmm0 and xmm1, which isn't what a real struct would do.
     ResTy = T.getArch() == Triple::x86_64
-                ? static_cast<Type *>(VectorType::get(ArgTy, 2))
+                ? static_cast<Type *>(FixedVectorType::get(ArgTy, 2))
                 : static_cast<Type *>(StructType::get(ArgTy, ArgTy));
   } else {
     Name = "__sincospi_stret";