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* [Bug tree-optimization/115224] New: (a ^ 1) & (a ^ ~1) is not optimized to 0 at the gimplelevel
@ 2024-05-25 4:59 pinskia at gcc dot gnu.org
2024-05-25 4:59 ` [Bug tree-optimization/115224] " pinskia at gcc dot gnu.org
` (4 more replies)
0 siblings, 5 replies; 6+ messages in thread
From: pinskia at gcc dot gnu.org @ 2024-05-25 4:59 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115224
Bug ID: 115224
Summary: (a ^ 1) & (a ^ ~1) is not optimized to 0 at the
gimplelevel
Product: gcc
Version: 15.0
Status: UNCONFIRMED
Keywords: missed-optimization, TREE
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: pinskia at gcc dot gnu.org
Target Milestone: ---
Take:
```
int f1(int a)
{
return (a ^ -2) & (a ^ 1);
}
int f2(int a, int b)
{
b = 1;
return (a ^ b) & (a ^ ~b);
}
int f3(int a, int b)
{
b = 1;
int t = a ^b;
int t1 = a ^ ~b;
return t & t1;
}
```
These all should be the same, GCC does optimize all to 0 but f1 and f3 is only
done on the RTL level.
This can be solved by improving bitwise_inverted_equal_p to see that `(a ^
CST)` and `(a ^ (~CST))` are inverse of each other.
^ permalink raw reply [flat|nested] 6+ messages in thread* [Bug tree-optimization/115224] (a ^ 1) & (a ^ ~1) is not optimized to 0 at the gimplelevel 2024-05-25 4:59 [Bug tree-optimization/115224] New: (a ^ 1) & (a ^ ~1) is not optimized to 0 at the gimplelevel pinskia at gcc dot gnu.org @ 2024-05-25 4:59 ` pinskia at gcc dot gnu.org 2024-05-27 1:05 ` pinskia at gcc dot gnu.org ` (3 subsequent siblings) 4 siblings, 0 replies; 6+ messages in thread From: pinskia at gcc dot gnu.org @ 2024-05-25 4:59 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115224 Andrew Pinski <pinskia at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Assignee|unassigned at gcc dot gnu.org |pinskia at gcc dot gnu.org Ever confirmed|0 |1 Last reconfirmed| |2024-05-25 Status|UNCONFIRMED |ASSIGNED --- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> --- MIne. found working on the `a - b` vs `b - a` patch. ^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug tree-optimization/115224] (a ^ 1) & (a ^ ~1) is not optimized to 0 at the gimplelevel 2024-05-25 4:59 [Bug tree-optimization/115224] New: (a ^ 1) & (a ^ ~1) is not optimized to 0 at the gimplelevel pinskia at gcc dot gnu.org 2024-05-25 4:59 ` [Bug tree-optimization/115224] " pinskia at gcc dot gnu.org @ 2024-05-27 1:05 ` pinskia at gcc dot gnu.org 2024-05-29 15:54 ` cvs-commit at gcc dot gnu.org ` (2 subsequent siblings) 4 siblings, 0 replies; 6+ messages in thread From: pinskia at gcc dot gnu.org @ 2024-05-27 1:05 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115224 Andrew Pinski <pinskia at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- URL| |https://gcc.gnu.org/piperma | |il/gcc-patches/2024-May/652 | |752.html Keywords| |patch --- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> --- https://gcc.gnu.org/pipermail/gcc-patches/2024-May/652752.html ^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug tree-optimization/115224] (a ^ 1) & (a ^ ~1) is not optimized to 0 at the gimplelevel 2024-05-25 4:59 [Bug tree-optimization/115224] New: (a ^ 1) & (a ^ ~1) is not optimized to 0 at the gimplelevel pinskia at gcc dot gnu.org 2024-05-25 4:59 ` [Bug tree-optimization/115224] " pinskia at gcc dot gnu.org 2024-05-27 1:05 ` pinskia at gcc dot gnu.org @ 2024-05-29 15:54 ` cvs-commit at gcc dot gnu.org 2024-05-29 16:00 ` pinskia at gcc dot gnu.org 2024-05-30 3:56 ` pinskia at gcc dot gnu.org 4 siblings, 0 replies; 6+ messages in thread From: cvs-commit at gcc dot gnu.org @ 2024-05-29 15:54 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115224 --- Comment #3 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The trunk branch has been updated by Andrew Pinski <pinskia@gcc.gnu.org>: https://gcc.gnu.org/g:547143df5aa0960fb149a26933dad7ca1c363afb commit r15-908-g547143df5aa0960fb149a26933dad7ca1c363afb Author: Andrew Pinski <quic_apinski@quicinc.com> Date: Sun May 26 17:38:37 2024 -0700 match: Add support for `a ^ CST` to bitwise_inverted_equal_p [PR115224] While looking into something else, I noticed that `a ^ CST` needed to be special casing to bitwise_inverted_equal_p as it would simplify to `a ^ ~CST` for the bitwise not. Bootstrapped and tested on x86_64-linux-gnu with no regressions. PR tree-optimization/115224 gcc/ChangeLog: * generic-match-head.cc (bitwise_inverted_equal_p): Add `a ^ CST` case. * gimple-match-head.cc (gimple_bit_xor_cst): New declaration. (gimple_bitwise_inverted_equal_p): Add `a ^ CST` case. * match.pd (bit_xor_cst): New match. (maybe_bit_not): Add bit_xor_cst case. gcc/testsuite/ChangeLog: * gcc.dg/tree-ssa/bitops-8.c: New test. Signed-off-by: Andrew Pinski <quic_apinski@quicinc.com> ^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug tree-optimization/115224] (a ^ 1) & (a ^ ~1) is not optimized to 0 at the gimplelevel 2024-05-25 4:59 [Bug tree-optimization/115224] New: (a ^ 1) & (a ^ ~1) is not optimized to 0 at the gimplelevel pinskia at gcc dot gnu.org ` (2 preceding siblings ...) 2024-05-29 15:54 ` cvs-commit at gcc dot gnu.org @ 2024-05-29 16:00 ` pinskia at gcc dot gnu.org 2024-05-30 3:56 ` pinskia at gcc dot gnu.org 4 siblings, 0 replies; 6+ messages in thread From: pinskia at gcc dot gnu.org @ 2024-05-29 16:00 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115224 Andrew Pinski <pinskia at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|ASSIGNED |RESOLVED Resolution|--- |FIXED Target Milestone|--- |15.0 --- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> --- Fixed. ^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug tree-optimization/115224] (a ^ 1) & (a ^ ~1) is not optimized to 0 at the gimplelevel 2024-05-25 4:59 [Bug tree-optimization/115224] New: (a ^ 1) & (a ^ ~1) is not optimized to 0 at the gimplelevel pinskia at gcc dot gnu.org ` (3 preceding siblings ...) 2024-05-29 16:00 ` pinskia at gcc dot gnu.org @ 2024-05-30 3:56 ` pinskia at gcc dot gnu.org 4 siblings, 0 replies; 6+ messages in thread From: pinskia at gcc dot gnu.org @ 2024-05-30 3:56 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115224 --- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> --- *** Bug 113072 has been marked as a duplicate of this bug. *** ^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2024-05-30 3:56 UTC | newest] Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2024-05-25 4:59 [Bug tree-optimization/115224] New: (a ^ 1) & (a ^ ~1) is not optimized to 0 at the gimplelevel pinskia at gcc dot gnu.org 2024-05-25 4:59 ` [Bug tree-optimization/115224] " pinskia at gcc dot gnu.org 2024-05-27 1:05 ` pinskia at gcc dot gnu.org 2024-05-29 15:54 ` cvs-commit at gcc dot gnu.org 2024-05-29 16:00 ` pinskia at gcc dot gnu.org 2024-05-30 3:56 ` pinskia at gcc dot gnu.org
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