[Bug tree-optimization/110941] [14 Regression] Dead Code Elimination Regression at -O3 since r14-2379-gc496d15954c
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110941 Andrew Pinski changed: What|Removed |Added Resolution|--- |FIXED Status|ASSIGNED|RESOLVED --- Comment #7 from Andrew Pinski --- Fixed.
[Bug tree-optimization/110941] [14 Regression] Dead Code Elimination Regression at -O3 since r14-2379-gc496d15954c
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110941 --- Comment #6 from GCC Commits --- The trunk branch has been updated by Andrew Pinski : https://gcc.gnu.org/g:34a827039fabcf24ce78da25984a1cc8be7ca2c3 commit r14-7221-g34a827039fabcf24ce78da25984a1cc8be7ca2c3 Author: Andrew Pinski Date: Fri Jan 12 20:24:34 2024 -0800 Add a few testcases for fix missed optimization regressions Adds a few new testcases for some missed optimization regressions. The analysis on how each should be optimized is in the testcases themselves (and in the bug report). Committed as obvious after running the testsuite to make sure they pass. PR tree-optimization/107823 PR tree-optimization/110768 PR tree-optimization/110941 PR tree-optimization/110450 PR tree-optimization/110841 gcc/testsuite/ChangeLog: * gcc.dg/tree-ssa/ssa-thread-22.c: New test. * gcc.dg/tree-ssa/vrp-loop-1.c: New test. * gcc.dg/tree-ssa/vrp-loop-2.c: New test. * gcc.dg/tree-ssa/vrp-unreachable-1.c: New test. * gcc.dg/tree-ssa/vrp-unreachable-2.c: New test. Signed-off-by: Andrew Pinski
[Bug tree-optimization/110941] [14 Regression] Dead Code Elimination Regression at -O3 since r14-2379-gc496d15954c
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110941 Andrew Pinski changed: What|Removed |Added Assignee|unassigned at gcc dot gnu.org |pinskia at gcc dot gnu.org Status|NEW |ASSIGNED --- Comment #5 from Andrew Pinski --- Will commit a testcase for this. r14-5109-ga291237b628f41 is definitely the fix for this based on my analysis in comment #2: > GCC 13: > Global Exported: _6 = [irange] unsigned int [0, 24] NONZERO 0x1e > trunk: > Global Exported: _6 = [irange] unsigned int [0, 24][+INF, +INF] MASK 0x1c > VALUE 0x0 The removal of `[+INF, +INF]` here fixes the issue earlier
[Bug tree-optimization/110941] [14 Regression] Dead Code Elimination Regression at -O3 since r14-2379-gc496d15954c
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110941 Martin Jambor changed: What|Removed |Added CC||jamborm at gcc dot gnu.org Keywords|needs-bisection | --- Comment #4 from Martin Jambor --- This has been fixed with r14-5109-ga291237b628f41 (Andrew MacLeod: Remove simple ranges from trailing zero bitmasks).
[Bug tree-optimization/110941] [14 Regression] Dead Code Elimination Regression at -O3 since r14-2379-gc496d15954c
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110941 Andrew Pinski changed: What|Removed |Added Keywords||needs-bisection --- Comment #3 from Andrew Pinski --- This seems to be fixed now. We are able to optimize out the call to foo even in evrp now too.
[Bug tree-optimization/110941] [14 Regression] Dead Code Elimination Regression at -O3 since r14-2379-gc496d15954c
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110941 --- Comment #2 from Andrew Pinski --- GCC 13: Global Exported: _6 = [irange] unsigned int [0, 24] NONZERO 0x1e trunk: Global Exported: _6 = [irange] unsigned int [0, 24][+INF, +INF] MASK 0x1c VALUE 0x0 And then: Folding predicate _6 > 24 to 0 does not happen. But what is interesting is with https://gcc.gnu.org/pipermail/gcc-patches/2023-September/629128.html , We get: ``` Simplified relational if (_6 > 24) into if (_6 == 4294967295) Folded into: if (_6 == 4294967295) ``` And then during cfgcleanup the match pattern: /* X == C (or X & Z == Y | C) is impossible if ~nonzero(X) & C != 0. */ Hits which is totally funny because that means the range and nonzero information are out of sync ...
[Bug tree-optimization/110941] [14 Regression] Dead Code Elimination Regression at -O3 since r14-2379-gc496d15954c
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110941 Andrew Pinski changed: What|Removed |Added Last reconfirmed||2023-08-08 Ever confirmed|0 |1 Status|UNCONFIRMED |NEW --- Comment #1 from Andrew Pinski --- # RANGE [irange] unsigned int [0, 16][20, 20][24, 24][65532, 4294901776][4294967293, +INF] MASK 0xfffc VALUE 0x0 # ivtmp.18_37 = PHI # RANGE [irange] unsigned short [0, +INF] MASK 0xfffc VALUE 0xfffc _21 = (unsigned short) ivtmp.18_37; if (_21 <= 24) Confirmed. The range for _21 is way to conserative. It should have been: `[0, 16][20, 20][24, 24]`.
[Bug tree-optimization/110941] [14 Regression] Dead Code Elimination Regression at -O3 since r14-2379-gc496d15954c
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110941 Richard Biener changed: What|Removed |Added Target Milestone|--- |14.0
