Add a new DAGCombine optimization for BUILD_VECTOR.
If all of the inputs are zero/any_extended, create a new simple BV
which can be further optimized by other BV optimizations.

llvm-svn: 143297
4 files changed
tree: f46cebcb9ed2bac9e4a013293b394f6cc289774e
  1. clang/
  2. compiler-rt/
  3. debuginfo-tests/
  4. libcxx/
  5. libcxxabi/
  6. lldb/
  7. llvm/
  8. polly/