[x86][inline-asm][clang] accept 'v' constraint
Commit in the name of: Coby Tayree
1.'v' constraint for (x86) non-avx arch imitates the already implemented 'x' constraint, i.e. allows XMM{0-15} & YMM{0-15} depending on the apparent arch & mode (32/64).
2.for the avx512 arch it allows [X,Y,Z]MM{0-31} (mode dependent)
This patch applies the needed changes to clang
LLVM patch: https://reviews.llvm.org/D25005
Differential Revision: D25004
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@283716
91177308-0d34-0410-b5e6-
96231b3b80d8