diff options
Diffstat (limited to 'gcc/fold-const.c')
| -rw-r--r-- | gcc/fold-const.c | 17 |
1 files changed, 14 insertions, 3 deletions
diff --git a/gcc/fold-const.c b/gcc/fold-const.c index f2591159184..c636bdc73ee 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -4397,6 +4397,18 @@ extract_muldiv (t, c, code, wide_type) break; case CONVERT_EXPR: case NON_LVALUE_EXPR: case NOP_EXPR: + /* If op0 is an expression, and is unsigned, and the type is + smaller than ctype, then we cannot widen the expression. */ + if ((TREE_CODE_CLASS (TREE_CODE (op0)) == '<' + || TREE_CODE_CLASS (TREE_CODE (op0)) == '1' + || TREE_CODE_CLASS (TREE_CODE (op0)) == '2' + || TREE_CODE_CLASS (TREE_CODE (op0)) == 'e') + && TREE_UNSIGNED (TREE_TYPE (op0)) + && ! TYPE_IS_SIZETYPE (TREE_TYPE (op0)) + && (GET_MODE_SIZE (TYPE_MODE (ctype)) + > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0))))) + break; + /* Pass the constant down and see if we can make a simplification. If we can, replace this expression with the inner simplification for possible later conversion to our or some other type. */ @@ -4413,7 +4425,7 @@ extract_muldiv (t, c, code, wide_type) case MIN_EXPR: case MAX_EXPR: /* If widening the type changes the signedness, then we can't perform this optimization as that changes the result. */ - if (ctype != type && TREE_UNSIGNED (ctype) != TREE_UNSIGNED (type)) + if (TREE_UNSIGNED (ctype) != TREE_UNSIGNED (type)) break; /* MIN (a, b) / 5 -> MIN (a / 5, b / 5) */ @@ -4581,8 +4593,7 @@ extract_muldiv (t, c, code, wide_type) this since it will change the result if the original computation overflowed. */ if ((! TREE_UNSIGNED (ctype) - || (TREE_CODE (ctype) == INTEGER_TYPE - && TYPE_IS_SIZETYPE (ctype))) + || TYPE_IS_SIZETYPE (ctype)) && ((code == MULT_EXPR && tcode == EXACT_DIV_EXPR) || (tcode == MULT_EXPR && code != TRUNC_MOD_EXPR && code != CEIL_MOD_EXPR |