https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105679
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Ever confirmed|0 |1
Last reconfirmed| |2022-07-29
Status|UNCONFIRMED |ASSIGNED
Assignee|unassigned at gcc dot gnu.org |rguenth at gcc dot
gnu.org
--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
Checking profitability of path (backwards): bb:5 (2 insns) bb:4 (7 insns) bb:3
Control statement insns: 2
Overall: 7 insns
[1] Registering jump thread: (3, 4) incoming edge; (4, 5) normal (5, 6)
nocopy;
path: 3->4->5->6 SUCCESS
but from the following you can see BB3 is known to probably never execute.
;; basic block 2, loop depth 0, count 1073741823 (estimated locally), maybe
hot
;; prev block 9, next block 3, flags: (NEW, REACHABLE, VISITED)
;; pred: 9 [always] count:1073741823 (estimated locally)
(FALLTHRU,EXECUTABLE)
if (irq_1(D) > 31)
goto <bb 3>; [0.00%]
else
goto <bb 4>; [100.00%]
;; basic block 3, loop depth 0, count 0 (precise), probably never executed
;; prev block 2, next block 4, flags: (NEW, REACHABLE, VISITED)
;; pred: 2 [never] count:0 (precise) (TRUE_VALUE,EXECUTABLE)
_2 = (unsigned long) irq_1(D);
__builtin___ubsan_handle_shift_out_of_bounds (&*.Lubsan_data0, 1, _2);
;; succ: 4 [never] count:0 (precise) (FALLTHRU,EXECUTABLE)
;; basic block 4, loop depth 0, count 1073741823 (estimated locally), maybe
hot
;; prev block 3, next block 5, flags: (NEW, REACHABLE, VISITED)
;; pred: 2 [always] count:1073741823 (estimated locally)
(FALSE_VALUE,EXECUTABLE)
;; 3 [never] count:0 (precise) (FALLTHRU,EXECUTABLE)
_3 = 1 << irq_1(D);
mask_4 = (u32) _3;
entry = instance_5(D)->array[irq_1(D)];
capture (mask_4);
if (level_6(D) != 0)
goto <bb 7>; [34.00%]
else
goto <bb 5>; [66.00%]
;; succ: 7 [34.0% (guessed)] count:365072224 (estimated locally)
(TRUE_VALUE,EXECUTABLE)
;; 5 [66.0% (guessed)] count:708669599 (estimated locally)
(FALSE_VALUE,EXECUTABLE)
;; basic block 5, loop depth 0, count 708669600 (estimated locally), maybe
hot
;; prev block 4, next block 6, flags: (NEW, REACHABLE, VISITED)
;; pred: 4 [66.0% (guessed)] count:708669599 (estimated locally)
(FALSE_VALUE,EXECUTABLE)
if (irq_1(D) == 1)
goto <bb 7>; [20.97%]
else
goto <bb 6>; [79.03%]
;; succ: 7 [21.0% (guessed)] count:148608017 (estimated locally)
(TRUE_VALUE,EXECUTABLE)
;; 6 [79.0% (guessed)] count:560061583 (estimated locally)
(FALSE_VALUE,EXECUTABLE)
