allow !strconcat to take more than two operands to eliminate
!strconcat(!strconcat(!strconcat(!strconcat

Simplify some x86 td files to use it.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115719 91177308-0d34-0410-b5e6-96231b3b80d8
4 files changed