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-rw-r--r--gcc/fold-const.c140
1 files changed, 7 insertions, 133 deletions
diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index f2e1cea..e22b02f 100644
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -10502,40 +10502,6 @@ fold_binary_loc (location_t loc,
&& code == NE_EXPR)
return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
- /* Transform comparisons of the form X +- Y CMP X to Y CMP 0. */
- if ((TREE_CODE (arg0) == PLUS_EXPR
- || TREE_CODE (arg0) == POINTER_PLUS_EXPR
- || TREE_CODE (arg0) == MINUS_EXPR)
- && operand_equal_p (tree_strip_nop_conversions (TREE_OPERAND (arg0,
- 0)),
- arg1, 0)
- && (INTEGRAL_TYPE_P (TREE_TYPE (arg0))
- || POINTER_TYPE_P (TREE_TYPE (arg0))))
- {
- tree val = TREE_OPERAND (arg0, 1);
- val = fold_build2_loc (loc, code, type, val,
- build_int_cst (TREE_TYPE (val), 0));
- return omit_two_operands_loc (loc, type, val,
- TREE_OPERAND (arg0, 0), arg1);
- }
-
- /* Transform comparisons of the form X CMP X +- Y to Y CMP 0. */
- if ((TREE_CODE (arg1) == PLUS_EXPR
- || TREE_CODE (arg1) == POINTER_PLUS_EXPR
- || TREE_CODE (arg1) == MINUS_EXPR)
- && operand_equal_p (tree_strip_nop_conversions (TREE_OPERAND (arg1,
- 0)),
- arg0, 0)
- && (INTEGRAL_TYPE_P (TREE_TYPE (arg1))
- || POINTER_TYPE_P (TREE_TYPE (arg1))))
- {
- tree val = TREE_OPERAND (arg1, 1);
- val = fold_build2_loc (loc, code, type, val,
- build_int_cst (TREE_TYPE (val), 0));
- return omit_two_operands_loc (loc, type, val,
- TREE_OPERAND (arg1, 0), arg0);
- }
-
/* If this is an EQ or NE comparison with zero and ARG0 is
(1 << foo) & bar, convert it to (bar >> foo) & 1. Both require
two operations, but the latter can be done in one less insn
@@ -10918,130 +10884,38 @@ fold_binary_loc (location_t loc,
/* Transform comparisons of the form X +- C CMP X. */
if ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
&& operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
- && ((TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
- && !HONOR_SNANS (arg0))
- || (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
- && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))))
+ && TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
+ && !HONOR_SNANS (arg0))
{
tree arg01 = TREE_OPERAND (arg0, 1);
enum tree_code code0 = TREE_CODE (arg0);
- int is_positive;
-
- if (TREE_CODE (arg01) == REAL_CST)
- is_positive = REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg01)) ? -1 : 1;
- else
- is_positive = tree_int_cst_sgn (arg01);
+ int is_positive = REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg01)) ? -1 : 1;
/* (X - c) > X becomes false. */
if (code == GT_EXPR
&& ((code0 == MINUS_EXPR && is_positive >= 0)
|| (code0 == PLUS_EXPR && is_positive <= 0)))
- {
- if (TREE_CODE (arg01) == INTEGER_CST
- && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
- fold_overflow_warning (("assuming signed overflow does not "
- "occur when assuming that (X - c) > X "
- "is always false"),
- WARN_STRICT_OVERFLOW_ALL);
- return constant_boolean_node (0, type);
- }
+ return constant_boolean_node (0, type);
/* Likewise (X + c) < X becomes false. */
if (code == LT_EXPR
&& ((code0 == PLUS_EXPR && is_positive >= 0)
|| (code0 == MINUS_EXPR && is_positive <= 0)))
- {
- if (TREE_CODE (arg01) == INTEGER_CST
- && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
- fold_overflow_warning (("assuming signed overflow does not "
- "occur when assuming that "
- "(X + c) < X is always false"),
- WARN_STRICT_OVERFLOW_ALL);
- return constant_boolean_node (0, type);
- }
+ return constant_boolean_node (0, type);
/* Convert (X - c) <= X to true. */
if (!HONOR_NANS (arg1)
&& code == LE_EXPR
&& ((code0 == MINUS_EXPR && is_positive >= 0)
|| (code0 == PLUS_EXPR && is_positive <= 0)))
- {
- if (TREE_CODE (arg01) == INTEGER_CST
- && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
- fold_overflow_warning (("assuming signed overflow does not "
- "occur when assuming that "
- "(X - c) <= X is always true"),
- WARN_STRICT_OVERFLOW_ALL);
- return constant_boolean_node (1, type);
- }
+ return constant_boolean_node (1, type);
/* Convert (X + c) >= X to true. */
if (!HONOR_NANS (arg1)
&& code == GE_EXPR
&& ((code0 == PLUS_EXPR && is_positive >= 0)
|| (code0 == MINUS_EXPR && is_positive <= 0)))
- {
- if (TREE_CODE (arg01) == INTEGER_CST
- && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
- fold_overflow_warning (("assuming signed overflow does not "
- "occur when assuming that "
- "(X + c) >= X is always true"),
- WARN_STRICT_OVERFLOW_ALL);
- return constant_boolean_node (1, type);
- }
-
- if (TREE_CODE (arg01) == INTEGER_CST)
- {
- /* Convert X + c > X and X - c < X to true for integers. */
- if (code == GT_EXPR
- && ((code0 == PLUS_EXPR && is_positive > 0)
- || (code0 == MINUS_EXPR && is_positive < 0)))
- {
- if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
- fold_overflow_warning (("assuming signed overflow does "
- "not occur when assuming that "
- "(X + c) > X is always true"),
- WARN_STRICT_OVERFLOW_ALL);
- return constant_boolean_node (1, type);
- }
-
- if (code == LT_EXPR
- && ((code0 == MINUS_EXPR && is_positive > 0)
- || (code0 == PLUS_EXPR && is_positive < 0)))
- {
- if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
- fold_overflow_warning (("assuming signed overflow does "
- "not occur when assuming that "
- "(X - c) < X is always true"),
- WARN_STRICT_OVERFLOW_ALL);
- return constant_boolean_node (1, type);
- }
-
- /* Convert X + c <= X and X - c >= X to false for integers. */
- if (code == LE_EXPR
- && ((code0 == PLUS_EXPR && is_positive > 0)
- || (code0 == MINUS_EXPR && is_positive < 0)))
- {
- if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
- fold_overflow_warning (("assuming signed overflow does "
- "not occur when assuming that "
- "(X + c) <= X is always false"),
- WARN_STRICT_OVERFLOW_ALL);
- return constant_boolean_node (0, type);
- }
-
- if (code == GE_EXPR
- && ((code0 == MINUS_EXPR && is_positive > 0)
- || (code0 == PLUS_EXPR && is_positive < 0)))
- {
- if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
- fold_overflow_warning (("assuming signed overflow does "
- "not occur when assuming that "
- "(X - c) >= X is always false"),
- WARN_STRICT_OVERFLOW_ALL);
- return constant_boolean_node (0, type);
- }
- }
+ return constant_boolean_node (1, type);
}
/* If we are comparing an ABS_EXPR with a constant, we can
generated by cgit v1.1 at 2025-08-09 04:39:20 +0000