On 01/12/2018 06:21 AM, Wilco Dijkstra wrote: > Hi, > > Here is the updated version: > > This patch implements some of the optimizations discussed in > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71026. > > Simplify (C / x >= 0.0) into x >= 0.0 with -fno-signed-zeros > and -ffinite-math-only. If C is negative the comparison is reversed. > Only handle >= and <= for now since C / x can underflow if C is small. > > > Simplify (x * C1) > C2 into x > (C2 / C1) with -funsafe-math-optimizations. > If C1 is negative the comparison is reversed. > > OK for commit? > > ChangeLog > 2018-01-10 Wilco Dijkstra <wdijk...@arm.com> > Jackson Woodruff <jackson.woodr...@arm.com> > > gcc/ > PR 71026/tree-optimization > * match.pd: Simplify floating point comparisons. > > gcc/testsuite/ > PR 71026/tree-optimization > * gcc.dg/div-cmp-1.c: New test. > * gcc.dg/div-cmp-2.c: New test. OK for the trunk. I don't think there is a need to backport to gcc-8.
jeff