http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59387
--- Comment #8 from Richard Biener <rguenth at gcc dot gnu.org> --- (In reply to Jakub Jelinek from comment #7) > Unfortunately it triggers (sccp no longer optimizes) on quite a few > testcases: > > gcc.c-torture/execute/pr58277-1.c > gcc.c-torture/execute/pr58831.c > gcc.c-torture/execute/pr59387.c > gcc.dg/pr58010.c > gcc.dg/torture/pr55481.c > gcc.dg/torture/pr56366.c > gcc.dg/torture/pr59058.c > gcc.dg/torture/pr59245.c > gcc.dg/tree-ssa/loop-32.c > gcc.dg/tree-ssa/loop-33.c > gcc.dg/tree-ssa/loop-35.c > gcc.dg/tree-ssa/scev-6.c > > (the first test only for -m64, all the rest both -m32 and -m64, the last > even FAILs because of that). Couldn't we just transform that somehow into > an unsigned type computation instead in that case, at least for simple cases? You could leverage the code I added to LIM ... in the case where SCEV folded casts, of course.
