diff options
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 7 | ||||
| -rw-r--r-- | gcc/fold-const.c | 12 |
2 files changed, 15 insertions, 4 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index ce01cd2..2704ad3 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +2006-11-12 Roger Sayle <roger@eyesopen.com> + + * fold-const.c (negate_expr_p) <PLUS_EXPR, MINUS_EXPR>: Correct/refine + condition for transformations. Use !HONOR_SIGN_DEPENDENT_ROUNDING + && !HONOR_SIGNED_ZEROS instead of flag_unsafe_math_optimizations. + (fold_negate_expr) <PLUS_EXPR, MINUS_EXPR>: Likewise. + 2006-11-12 Daniel Berlin <dberlin@dberlin.org> Fix PR tree-optimization/29587 diff --git a/gcc/fold-const.c b/gcc/fold-const.c index eeec0c1..c986503 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -981,7 +981,8 @@ negate_expr_p (tree t) && negate_expr_p (TREE_IMAGPART (t)); case PLUS_EXPR: - if (FLOAT_TYPE_P (type) && !flag_unsafe_math_optimizations) + if (HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type)) + || HONOR_SIGNED_ZEROS (TYPE_MODE (type))) return false; /* -(A + B) -> (-B) - A. */ if (negate_expr_p (TREE_OPERAND (t, 1)) @@ -993,7 +994,8 @@ negate_expr_p (tree t) case MINUS_EXPR: /* We can't turn -(A-B) into B-A when we honor signed zeros. */ - return (! FLOAT_TYPE_P (type) || flag_unsafe_math_optimizations) + return !HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type)) + && !HONOR_SIGNED_ZEROS (TYPE_MODE (type)) && reorder_operands_p (TREE_OPERAND (t, 0), TREE_OPERAND (t, 1)); @@ -1105,7 +1107,8 @@ fold_negate_expr (tree t) return TREE_OPERAND (t, 0); case PLUS_EXPR: - if (! FLOAT_TYPE_P (type) || flag_unsafe_math_optimizations) + if (!HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type)) + && !HONOR_SIGNED_ZEROS (TYPE_MODE (type))) { /* -(A + B) -> (-B) - A. */ if (negate_expr_p (TREE_OPERAND (t, 1)) @@ -1129,7 +1132,8 @@ fold_negate_expr (tree t) case MINUS_EXPR: /* - (A - B) -> B - A */ - if ((! FLOAT_TYPE_P (type) || flag_unsafe_math_optimizations) + if (!HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type)) + && !HONOR_SIGNED_ZEROS (TYPE_MODE (type)) && reorder_operands_p (TREE_OPERAND (t, 0), TREE_OPERAND (t, 1))) return fold_build2 (MINUS_EXPR, type, TREE_OPERAND (t, 1), TREE_OPERAND (t, 0)); |