[PATCH] D69244: [InstCombine] Extra combine for uadd_sat

[Roman Lebedev via Phabricator via llvm-commits]

lebedev.ri added a comment.

Err, make that two:
https://godbolt.org/z/F4uPIw

  ----------------------------------------
    %2 = icmp ugt i32 %0, 1
    %3 = add i32 %0, -2
    %4 = select i1 %2, i32 %3, i32 0
    ret i32 %4
  =>
    %4 = usub_sat i32 %0, 2
    ret i32 %4
    %3 = add i32 %0, -2
    %2 = icmp ugt i32 %0, 1
  
  Done: 1
  Optimization is correct!


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D69244/new/

https://reviews.llvm.org/D69244