https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115636
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Last reconfirmed| |2024-06-25
Ever confirmed|0 |1
Status|UNCONFIRMED |NEW
--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
;; basic block 3, loop depth 0, maybe hot
;; prev block 2, next block 4, flags: (NEW, VISITED)
;; pred: 2 (TRUE_VALUE,EXECUTABLE)
# VUSE <.MEM_13(D)>
b.1_2 = bD.4438;
# RANGE [irange] unsigned int [0, 32767][4294934528, +INF]
_3 = (unsigned intD.15) b.1_2;
# RANGE [irange] unsigned int [4294901760, +INF]
iftmp.0_14 = _3 + 4294934528;
goto <bb 5>; [INV]
;; succ: 5 (FALLTHRU,EXECUTABLE)
;; basic block 4, loop depth 0, maybe hot
;; prev block 3, next block 5, flags: (NEW, VISITED)
;; pred: 2 (FALSE_VALUE,EXECUTABLE)
_4 = (unsigned intD.15) a_11(D);
iftmp.0_12 = _4 + 4294934528;
;; succ: 5 (FALLTHRU,EXECUTABLE)
;; basic block 5, loop depth 0, maybe hot
;; prev block 4, next block 1, flags: (NEW, VISITED)
;; pred: 3 (FALLTHRU,EXECUTABLE)
;; 4 (FALLTHRU,EXECUTABLE)
# iftmp.0_8 = PHI <iftmp.0_14(3), iftmp.0_12(4)>
_5 = _1 << iftmp.0_8;
So we could see that bb3 is undefined due to the shift right afterwards and
either change it to being __builtin_unreachable or __builtin_trap and then
optimize it further.
This is a job for gimple-ssa-isolate-paths to handle really.
