HomePhabricator

[InstCombine] (-NSW x) s> x --> x s< 0 (PR39480)

Authored by lebedev.ri on Aug 6 2020, 12:45 AM.

Description

[InstCombine] (-NSW x) s> x --> x s< 0 (PR39480)

Name: (-x) s> x --> x s< 0
%neg_x = sub nsw i8 0, %x ; %x must not be INT_MIN
%r = icmp sgt i8 %neg_x, %x

=>

%r = icmp slt i8 %x, 0

https://rise4fun.com/Alive/ZslD

https://bugs.llvm.org/show_bug.cgi?id=39480

Details

Committed
lebedev.riAug 6 2020, 1:50 AM
Parents
rG664e1784cd5e: [NFC][InstCombine] Add tests for comparisons between x and negation of x…
Branches
Unknown
Tags
Unknown