Improve wording to make it sounds more like a change than an analysis.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208370 91177308-0d34-0410-b5e6-96231b3b80d8
[TargetInstrInfo] Fix the implementation of commuteInstruction to match the
comment of the API.

Relaxes the behavior of TargetInstrInfo::commuteInstruction when
TargetInstrInfo::findCommutedOpIndices returns false.

Previously TargetInstrInfo triggered a fatal error in such situation whereas based
on the comment in the API it should just return nullptr. Indeed the only
precondition that should be ensured is that the instruction must be commutable.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208371 91177308-0d34-0410-b5e6-96231b3b80d8
Optimize shufflevector that copies an i64/f64 and zeros the rest.

Summary:
Also ran clang-format on the function. The code added is the last else
if block.

Reviewers: nadav, craig.topper, delena

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D3518

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208372 91177308-0d34-0410-b5e6-96231b3b80d8