[X86][SSE] Fix PerformSExtCombine bug that accessed the wrong return value of an aggregate type.

Fix to rL237885 to ensure that it accesses the correct return value of an aggregate type.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240223 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed