cranelift: simplify ineg(ineg(x)) to x (#6033)

2023-03-16 22:14:05 +00:00
parent 07136ae96d
commit dccc2d6269
2 changed files with 11 additions and 0 deletions
--- a/cranelift/codegen/src/opts/algebraic.isle
+++ b/cranelift/codegen/src/opts/algebraic.isle
@@ -32,6 +32,9 @@
                      x))
      (ineg ty x))

+;; ineg(ineg(x)) == x.
+(rule (simplify (ineg ty (ineg ty x))) (subsume x))
+
 ;; x*1 == 1*x == x.
 (rule (simplify (imul ty
                      x