[PATCH] D21854: Remove AND mask of bottom 6 bits when result is used for SystemZ shift/rotate

[Ulrich Weigand via llvm-commits]

uweigand added a comment.

I'm not sure that adding so many extra patterns in the .td file is the best way to implement this.   Maybe it would be better to implement the transformation of the mask in PerformDAGCombine?  This is done earlier, and might in theory expose more combination opportunities ...


http://reviews.llvm.org/D21854