[DAGCombiner] Fold CONCAT_VECTORS of bitcasted EXTRACT_SUBVECTOR
authorSimon Pilgrim <llvm-dev@redking.me.uk>
Sun, 23 Aug 2015 15:22:14 +0000 (15:22 +0000)
committerSimon Pilgrim <llvm-dev@redking.me.uk>
Sun, 23 Aug 2015 15:22:14 +0000 (15:22 +0000)
commit7b7cb4251e43deb536df2e39b221a70f770db354
treefb1c2bb777958e2226d26cc042fdc1916f0f12cf
parenta99b9646625355d9a22d8d347217d166b026b8ce
[DAGCombiner] Fold CONCAT_VECTORS of bitcasted EXTRACT_SUBVECTOR

Minor generalization of D12125 - peek through any bitcast to the original vector that we're extracting from.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@245814 91177308-0d34-0410-b5e6-96231b3b80d8
lib/CodeGen/SelectionDAG/DAGCombiner.cpp
test/CodeGen/X86/vector-shuffle-256-v8.ll