diff options
Diffstat (limited to 'gcc/combine.c')
| -rw-r--r-- | gcc/combine.c | 11 |
1 files changed, 4 insertions, 7 deletions
diff --git a/gcc/combine.c b/gcc/combine.c index 2d46a69..911ebbf 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -10452,13 +10452,10 @@ simplify_comparison (code, pop0, pop1) break; case MINUS: - /* (op (minus A B) 0) -> (op A B) */ - if (op1 == const0_rtx) - { - op1 = XEXP (op0, 1); - op0 = XEXP (op0, 0); - continue; - } + /* We used to optimize signed comparisons against zero, but that + was incorrect. Unsigned comparisons against zero (GTU, LEU) + arrive here as equality comparisons, or (GEU, LTU) are + optimized away. No need to special-case them. */ /* (eq (minus A B) C) -> (eq A (plus B C)) or (eq B (minus A C)), whichever simplifies. We can only do |