[InstCombine] Fold abs(-x) -> abs(x)
Negating the input doesn't matter. I left a FIXME to copy the nsw flag if its present on the neg but not on the abs.
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D85055
craig.topper on Sat, Aug 1, 9:59 AM.Authored by