diff options
| author | Marc Glisse <marc.glisse@inria.fr> | 2020-08-10 12:50:42 +0200 |
|---|---|---|
| committer | Giuliano Belinassi <giuliano.belinassi@usp.br> | 2020-08-17 15:07:54 -0300 |
| commit | 429181b1ac18d008cd83da586350ac631e7b5787 (patch) | |
| tree | 3cfb40852b82921ec5aeb8741af1fa8492528f51 /gcc/cp/constexpr.c | |
| parent | 001a9a3b85b1c103992e2b4d5ce586263c3c5590 (diff) | |
| download | gcc-429181b1ac18d008cd83da586350ac631e7b5787.zip gcc-429181b1ac18d008cd83da586350ac631e7b5787.tar.gz gcc-429181b1ac18d008cd83da586350ac631e7b5787.tar.bz2 | |
Simplify X * C1 == C2 with wrapping overflow
Odd numbers are invertible in Z / 2^n Z, so X * C1 == C2 can be rewritten
as X == C2 * inv(C1) when overflow wraps.
mod_inv should probably be updated to better match the other wide_int
functions, but that's a separate issue.
2020-08-10 Marc Glisse <marc.glisse@inria.fr>
PR tree-optimization/95433
* match.pd (X * C1 == C2): Handle wrapping overflow.
* expr.c (maybe_optimize_mod_cmp): Qualify call to mod_inv.
(mod_inv): Move...
* wide-int.cc (mod_inv): ... here.
* wide-int.h (mod_inv): Declare it.
* gcc.dg/tree-ssa/pr95433-2.c: New file.
Diffstat (limited to 'gcc/cp/constexpr.c')
0 files changed, 0 insertions, 0 deletions