[Bug tree-optimization/93334] -O3 generates useless code checking for overlapping memset ?

2021-12-19 Thread pinskia at gcc dot gnu.org via Gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93334 Andrew Pinski changed: What|Removed |Added Severity|normal |enhancement

[Bug tree-optimization/93334] -O3 generates useless code checking for overlapping memset ?

2020-01-21 Thread nathanael.schaeffer at gmail dot com
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93334 --- Comment #5 from N Schaeffer --- Elaborating a bit on this: I can eliminate this problem by using: -O3 -fno-tree-loop-distribute-patterns -fno-tree-loop-vectorize I wonder why -fno-tree-loop-distribute-patterns is not enough ? In that

[Bug tree-optimization/93334] -O3 generates useless code checking for overlapping memset ?

2020-01-21 Thread jakub at gcc dot gnu.org
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93334 Jakub Jelinek changed: What|Removed |Added CC||jakub at gcc dot gnu.org --- Comment #4

[Bug tree-optimization/93334] -O3 generates useless code checking for overlapping memset ?

2020-01-21 Thread nathanael.schaeffer at gmail dot com
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93334 --- Comment #3 from N Schaeffer --- Hi, Thanks for pointing out the issue about writing different values. This makes sense. However, since memset deals with bytes, whenever the type of array is floating point data (or anything longer than

[Bug tree-optimization/93334] -O3 generates useless code checking for overlapping memset ?

2020-01-21 Thread amker at gcc dot gnu.org
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93334 --- Comment #2 from bin cheng --- (In reply to Richard Biener from comment #1) > Confirmed. The issue is that the overlap would be an issue if the stores > were using different values like > > void test_simple_code(long l, double* mem, long

[Bug tree-optimization/93334] -O3 generates useless code checking for overlapping memset ?

2020-01-21 Thread rguenth at gcc dot gnu.org
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93334 Richard Biener changed: What|Removed |Added Status|UNCONFIRMED |NEW Last reconfirmed|