https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71026
--- Comment #11 from Wilco <wilco at gcc dot gnu.org> --- Author: wilco Date: Wed Nov 14 12:45:29 2018 New Revision: 266142 URL: https://gcc.gnu.org/viewcvs?rev=266142&root=gcc&view=rev Log: Simplify floating point comparisons This patch implements some of the optimizations discussed in PR71026. Simplify (C / x >= 0.0) into x >= 0.0 with -funsafe-math-optimizations (since C / x can underflow to zero if x is huge, it's not safe otherwise). If C is negative the comparison is reversed. Simplify (x * C1) > C2 into x > (C2 / C1) with -funsafe-math-optimizations. If C1 is negative the comparison is reversed. 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. Added: trunk/gcc/testsuite/gcc.dg/div-cmp-1.c trunk/gcc/testsuite/gcc.dg/div-cmp-2.c Modified: trunk/gcc/ChangeLog trunk/gcc/match.pd trunk/gcc/testsuite/ChangeLog
