diff options
Diffstat (limited to 'gcc/fold-const.c')
| -rw-r--r-- | gcc/fold-const.c | 45 |
1 files changed, 35 insertions, 10 deletions
diff --git a/gcc/fold-const.c b/gcc/fold-const.c index 65a6d85efc0..adcb1877d83 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -1215,7 +1215,9 @@ int_const_binop (code, arg1, arg2, notrunc, forsize) } if (TREE_TYPE (arg1) == sizetype && hi == 0 - && low >= 0 && low <= TREE_INT_CST_LOW (TYPE_MAX_VALUE (sizetype)) + && low >= 0 + && (TYPE_MAX_VALUE (sizetype) == NULL + || low <= TREE_INT_CST_LOW (TYPE_MAX_VALUE (sizetype))) && ! overflow && ! TREE_OVERFLOW (arg1) && ! TREE_OVERFLOW (arg2)) t = size_int (low); @@ -1532,25 +1534,34 @@ fold_convert (t, arg1) REAL_VALUE_TYPE l; REAL_VALUE_TYPE u; tree type1 = TREE_TYPE (arg1); + int no_upper_bound; x = TREE_REAL_CST (arg1); l = real_value_from_int_cst (type1, TYPE_MIN_VALUE (type)); - u = real_value_from_int_cst (type1, TYPE_MAX_VALUE (type)); + + no_upper_bound = (TYPE_MAX_VALUE (type) == NULL); + if (!no_upper_bound) + u = real_value_from_int_cst (type1, TYPE_MAX_VALUE (type)); + /* See if X will be in range after truncation towards 0. To compensate for truncation, move the bounds away from 0, but reject if X exactly equals the adjusted bounds. */ #ifdef REAL_ARITHMETIC REAL_ARITHMETIC (l, MINUS_EXPR, l, dconst1); - REAL_ARITHMETIC (u, PLUS_EXPR, u, dconst1); + if (!no_upper_bound) + REAL_ARITHMETIC (u, PLUS_EXPR, u, dconst1); #else l--; - u++; + if (!no_upper_bound) + u++; #endif /* If X is a NaN, use zero instead and show we have an overflow. Otherwise, range check. */ if (REAL_VALUE_ISNAN (x)) overflow = 1, x = dconst0; - else if (! (REAL_VALUES_LESS (l, x) && REAL_VALUES_LESS (x, u))) + else if (! (REAL_VALUES_LESS (l, x) + && !no_upper_bound + && REAL_VALUES_LESS (x, u))) overflow = 1; #ifndef REAL_ARITHMETIC @@ -2922,11 +2933,22 @@ make_range (exp, pin_p, plow, phigh) if (TREE_UNSIGNED (type) && ! TREE_UNSIGNED (TREE_TYPE (exp))) { tree equiv_type = type_for_mode (TYPE_MODE (type), 1); - tree high_positive - = fold (build (RSHIFT_EXPR, type, - convert (type, - TYPE_MAX_VALUE (equiv_type)), - convert (type, integer_one_node))); + tree high_positive; + + /* A range without an upper bound is, naturally, unbounded. + Since convert would have cropped a very large value, use + the max value for the destination type. */ + + high_positive = TYPE_MAX_VALUE (equiv_type); + if (!high_positive) + { + high_positive = TYPE_MAX_VALUE (type); + if (!high_positive) + abort(); + } + high_positive = fold (build (RSHIFT_EXPR, type, + convert (type, high_positive), + convert (type, integer_one_node))); /* If the low bound is specified, "and" the range with the range for which the original unsigned value will be @@ -4914,6 +4936,7 @@ fold (expr) if (operand_equal_p (arg0, arg1, 0)) return arg0; if (INTEGRAL_TYPE_P (type) + && TYPE_MAX_VALUE (type) && operand_equal_p (arg1, TYPE_MAX_VALUE (type), 1)) return omit_one_operand (type, arg1, arg0); goto associate; @@ -5397,6 +5420,8 @@ fold (expr) && ! (TREE_CONSTANT (cval1) && TREE_CONSTANT (cval2)) && TREE_TYPE (cval1) == TREE_TYPE (cval2) && INTEGRAL_TYPE_P (TREE_TYPE (cval1)) + && TYPE_MAX_VALUE (TREE_TYPE (cval1)) + && TYPE_MAX_VALUE (TREE_TYPE (cval2)) && ! operand_equal_p (TYPE_MIN_VALUE (TREE_TYPE (cval1)), TYPE_MAX_VALUE (TREE_TYPE (cval2)), 0)) { |