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* [Bug tree-optimization/112356] New: `x == MIN & x > y` is not optimized to 0 if x was casted to signed from unsigned
@ 2023-11-02 20:53 pinskia at gcc dot gnu.org
2023-11-02 20:53 ` [Bug tree-optimization/112356] " pinskia at gcc dot gnu.org
2023-11-02 21:00 ` pinskia at gcc dot gnu.org
0 siblings, 2 replies; 3+ messages in thread
From: pinskia at gcc dot gnu.org @ 2023-11-02 20:53 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112356
Bug ID: 112356
Summary: `x == MIN & x > y` is not optimized to 0 if x was
casted to signed from unsigned
Product: gcc
Version: 14.0
Status: UNCONFIRMED
Keywords: missed-optimization
Severity: enhancement
Priority: P3
Component: tree-optimization
Assignee: pinskia at gcc dot gnu.org
Reporter: pinskia at gcc dot gnu.org
Target Milestone: ---
Take:
```
#include <limits.h>
signed f2_1( unsigned x, signed y)
{
signed xs = x;
signed t = x == INT_MIN;
signed t1 = xs > y;
return t & t1;
}
```
This is not optimized to 0.
^ permalink raw reply [flat|nested] 3+ messages in thread* [Bug tree-optimization/112356] `x == MIN & x > y` is not optimized to 0 if x was casted to signed from unsigned 2023-11-02 20:53 [Bug tree-optimization/112356] New: `x == MIN & x > y` is not optimized to 0 if x was casted to signed from unsigned pinskia at gcc dot gnu.org @ 2023-11-02 20:53 ` pinskia at gcc dot gnu.org 2023-11-02 21:00 ` pinskia at gcc dot gnu.org 1 sibling, 0 replies; 3+ messages in thread From: pinskia at gcc dot gnu.org @ 2023-11-02 20:53 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112356 Andrew Pinski <pinskia at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |ASSIGNED Ever confirmed|0 |1 Last reconfirmed| |2023-11-02 ^ permalink raw reply [flat|nested] 3+ messages in thread
* [Bug tree-optimization/112356] `x == MIN & x > y` is not optimized to 0 if x was casted to signed from unsigned 2023-11-02 20:53 [Bug tree-optimization/112356] New: `x == MIN & x > y` is not optimized to 0 if x was casted to signed from unsigned pinskia at gcc dot gnu.org 2023-11-02 20:53 ` [Bug tree-optimization/112356] " pinskia at gcc dot gnu.org @ 2023-11-02 21:00 ` pinskia at gcc dot gnu.org 1 sibling, 0 replies; 3+ messages in thread From: pinskia at gcc dot gnu.org @ 2023-11-02 21:00 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112356 --- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> --- The problem is we can't use `(match min_value` here but rather we need to change it from: ``` (for eqne (eq ne) (simplify (bit_and:c (gt:c@2 @0 @1) (eqne @0 min_value)) ``` to: ``` (for eqne (eq ne) (simplify (bit_and:c (gt:c@2 @0 @1) (eqne @3 uniform_integer_cst_p@2)) (if (bitwise_equal_p (@0, @3) && min_value_p (TREE_TYPE (@0), uniform_integer_cst_p (@2)) ``` Etc. We could have min_value_p use uniform_integer_cst_p inside it instead of doing it before hand. ^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2023-11-02 21:00 UTC | newest] Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2023-11-02 20:53 [Bug tree-optimization/112356] New: `x == MIN & x > y` is not optimized to 0 if x was casted to signed from unsigned pinskia at gcc dot gnu.org 2023-11-02 20:53 ` [Bug tree-optimization/112356] " pinskia at gcc dot gnu.org 2023-11-02 21:00 ` pinskia at gcc dot gnu.org
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