https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101481
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Ever confirmed|0 |1
Keywords| |missed-optimization
Target Milestone|--- |11.2
Last reconfirmed| |2021-07-17
Summary|-ftree-loop-distribute-patt |[11/12 Regression]
|erns can slow down and |-ftree-loop-distribute-patt
|increases size of code |erns can slow down and
| |increases size of code
Status|UNCONFIRMED |NEW
--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Confirmed. The ranges should be figured out that the max size is 4.
In fact GCC knows the range really (note I think it is really [0,2] but that is
a different issue) and the loop bounds is max 4.
;; basic block 6, loop depth 1, count 805306369 (estimated locally), maybe
hot
;; prev block 8, next block 9, flags: (NEW, REACHABLE, VISITED)
;; pred: 9 [always] count:603979777 (estimated locally)
(FALLTHRU,DFS_BACK)
;; 8 [always] count:201326592 (estimated locally) (FALLTHRU)
# RANGE [-1, 2]
# i_17 = PHI <i_16(9), i_11(8)>
# .MEM_21 = PHI <.MEM_15(9), .MEM_9(D)(8)>
# RANGE [1, 3] NONZERO 3
_4 = i_17 + 1;
# VUSE <.MEM_21>
_5 = a_10(D)->chunksD.1943[i_17];
# .MEM_15 = VDEF <.MEM_21>
a_10(D)->chunksD.1943[_4] = _5;
# RANGE [-1, 1]
i_16 = i_17 + -1;
if (i_16 >= _20)
goto <bb 9>; [75.00%]
else
goto <bb 7>; [25.00%]
;; succ: 9 [75.0% (guessed)] count:603979777 (estimated locally)
(TRUE_VALUE,EXECUTABLE)
;; 7 [25.0% (guessed)] count:201326592 (estimated locally)
(FALSE_VALUE,EXECUTABLE)
;; basic block 9, loop depth 1, count 603979777 (estimated locally), maybe
hot
;; prev block 6, next block 7, flags: (NEW)
;; pred: 6 [75.0% (guessed)] count:603979777 (estimated locally)
(TRUE_VALUE,EXECUTABLE)
goto <bb 6>; [100.00%]
;; succ: 6 [always] count:603979777 (estimated locally)
(FALLTHRU,DFS_BACK)
