1. Use pxor instead of xoraps / xorapd to clear FR32 / FR64 registers. This

1. Use pxor instead of xoraps / xorapd to clear FR32 / FR64 registers. This
   proves to be worth 20% on Ptrdist/ks. Might be related to dependency
   breaking support.
2. Added FsMOVAPSrr and FsMOVAPDrr as aliases to MOVAPSrr and MOVAPDrr. These
   are used for FR32 / FR64 reg-to-reg copies.
3. Tell reg-allocator to generate MOVSSrm / MOVSDrm and MOVSSmr / MOVSDmr to
   spill / restore FsMOVAPSrr and FsMOVAPDrr.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26241 91177308-0d34-0410-b5e6-96231b3b80d8