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-rw-r--r--gcc/fold-const.c262
1 files changed, 260 insertions, 2 deletions
diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index ddf18f2..31c48da 100644
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -13701,6 +13701,248 @@ multiple_of_p (tree type, const_tree top, const_tree bottom)
}
}
+/* Return true if expression X cannot be (or contain) a NaN or infinity.
+ This function returns true for integer expressions, and returns
+ false if uncertain. */
+
+bool
+tree_expr_finite_p (const_tree x)
+{
+ machine_mode mode = element_mode (x);
+ if (!HONOR_NANS (mode) && !HONOR_INFINITIES (mode))
+ return true;
+ switch (TREE_CODE (x))
+ {
+ case REAL_CST:
+ return real_isfinite (TREE_REAL_CST_PTR (x));
+ case COMPLEX_CST:
+ return tree_expr_finite_p (TREE_REALPART (x))
+ && tree_expr_finite_p (TREE_IMAGPART (x));
+ case FLOAT_EXPR:
+ return true;
+ case ABS_EXPR:
+ case CONVERT_EXPR:
+ case NON_LVALUE_EXPR:
+ case NEGATE_EXPR:
+ case SAVE_EXPR:
+ return tree_expr_finite_p (TREE_OPERAND (x, 0));
+ case MIN_EXPR:
+ case MAX_EXPR:
+ return tree_expr_finite_p (TREE_OPERAND (x, 0))
+ && tree_expr_finite_p (TREE_OPERAND (x, 1));
+ case COND_EXPR:
+ return tree_expr_finite_p (TREE_OPERAND (x, 1))
+ && tree_expr_finite_p (TREE_OPERAND (x, 2));
+ case CALL_EXPR:
+ switch (get_call_combined_fn (x))
+ {
+ CASE_CFN_FABS:
+ return tree_expr_finite_p (CALL_EXPR_ARG (x, 0));
+ CASE_CFN_FMAX:
+ CASE_CFN_FMIN:
+ return tree_expr_finite_p (CALL_EXPR_ARG (x, 0))
+ && tree_expr_finite_p (CALL_EXPR_ARG (x, 1));
+ default:
+ return false;
+ }
+
+ default:
+ return false;
+ }
+}
+
+/* Return true if expression X evaluates to an infinity.
+ This function returns false for integer expressions. */
+
+bool
+tree_expr_infinite_p (const_tree x)
+{
+ if (!HONOR_INFINITIES (x))
+ return false;
+ switch (TREE_CODE (x))
+ {
+ case REAL_CST:
+ return real_isinf (TREE_REAL_CST_PTR (x));
+ case ABS_EXPR:
+ case NEGATE_EXPR:
+ case NON_LVALUE_EXPR:
+ case SAVE_EXPR:
+ return tree_expr_infinite_p (TREE_OPERAND (x, 0));
+ case COND_EXPR:
+ return tree_expr_infinite_p (TREE_OPERAND (x, 1))
+ && tree_expr_infinite_p (TREE_OPERAND (x, 2));
+ default:
+ return false;
+ }
+}
+
+/* Return true if expression X could evaluate to an infinity.
+ This function returns false for integer expressions, and returns
+ true if uncertain. */
+
+bool
+tree_expr_maybe_infinite_p (const_tree x)
+{
+ if (!HONOR_INFINITIES (x))
+ return false;
+ switch (TREE_CODE (x))
+ {
+ case REAL_CST:
+ return real_isinf (TREE_REAL_CST_PTR (x));
+ case FLOAT_EXPR:
+ return false;
+ case ABS_EXPR:
+ case NEGATE_EXPR:
+ return tree_expr_maybe_infinite_p (TREE_OPERAND (x, 0));
+ case COND_EXPR:
+ return tree_expr_maybe_infinite_p (TREE_OPERAND (x, 1))
+ || tree_expr_maybe_infinite_p (TREE_OPERAND (x, 2));
+ default:
+ return true;
+ }
+}
+
+/* Return true if expression X evaluates to a signaling NaN.
+ This function returns false for integer expressions. */
+
+bool
+tree_expr_signaling_nan_p (const_tree x)
+{
+ if (!HONOR_SNANS (x))
+ return false;
+ switch (TREE_CODE (x))
+ {
+ case REAL_CST:
+ return real_issignaling_nan (TREE_REAL_CST_PTR (x));
+ case NON_LVALUE_EXPR:
+ case SAVE_EXPR:
+ return tree_expr_signaling_nan_p (TREE_OPERAND (x, 0));
+ case COND_EXPR:
+ return tree_expr_signaling_nan_p (TREE_OPERAND (x, 1))
+ && tree_expr_signaling_nan_p (TREE_OPERAND (x, 2));
+ default:
+ return false;
+ }
+}
+
+/* Return true if expression X could evaluate to a signaling NaN.
+ This function returns false for integer expressions, and returns
+ true if uncertain. */
+
+bool
+tree_expr_maybe_signaling_nan_p (const_tree x)
+{
+ if (!HONOR_SNANS (x))
+ return false;
+ switch (TREE_CODE (x))
+ {
+ case REAL_CST:
+ return real_issignaling_nan (TREE_REAL_CST_PTR (x));
+ case FLOAT_EXPR:
+ return false;
+ case ABS_EXPR:
+ case CONVERT_EXPR:
+ case NEGATE_EXPR:
+ case NON_LVALUE_EXPR:
+ case SAVE_EXPR:
+ return tree_expr_maybe_signaling_nan_p (TREE_OPERAND (x, 0));
+ case MIN_EXPR:
+ case MAX_EXPR:
+ return tree_expr_maybe_signaling_nan_p (TREE_OPERAND (x, 0))
+ || tree_expr_maybe_signaling_nan_p (TREE_OPERAND (x, 1));
+ case COND_EXPR:
+ return tree_expr_maybe_signaling_nan_p (TREE_OPERAND (x, 1))
+ || tree_expr_maybe_signaling_nan_p (TREE_OPERAND (x, 2));
+ case CALL_EXPR:
+ switch (get_call_combined_fn (x))
+ {
+ CASE_CFN_FABS:
+ return tree_expr_maybe_signaling_nan_p (CALL_EXPR_ARG (x, 0));
+ CASE_CFN_FMAX:
+ CASE_CFN_FMIN:
+ return tree_expr_maybe_signaling_nan_p (CALL_EXPR_ARG (x, 0))
+ || tree_expr_maybe_signaling_nan_p (CALL_EXPR_ARG (x, 1));
+ default:
+ return true;
+ }
+ default:
+ return true;
+ }
+}
+
+/* Return true if expression X evaluates to a NaN.
+ This function returns false for integer expressions. */
+
+bool
+tree_expr_nan_p (const_tree x)
+{
+ if (!HONOR_NANS (x))
+ return false;
+ switch (TREE_CODE (x))
+ {
+ case REAL_CST:
+ return real_isnan (TREE_REAL_CST_PTR (x));
+ case NON_LVALUE_EXPR:
+ case SAVE_EXPR:
+ return tree_expr_nan_p (TREE_OPERAND (x, 0));
+ case COND_EXPR:
+ return tree_expr_nan_p (TREE_OPERAND (x, 1))
+ && tree_expr_nan_p (TREE_OPERAND (x, 2));
+ default:
+ return false;
+ }
+}
+
+/* Return true if expression X could evaluate to a NaN.
+ This function returns false for integer expressions, and returns
+ true if uncertain. */
+
+bool
+tree_expr_maybe_nan_p (const_tree x)
+{
+ if (!HONOR_NANS (x))
+ return false;
+ switch (TREE_CODE (x))
+ {
+ case REAL_CST:
+ return real_isnan (TREE_REAL_CST_PTR (x));
+ case FLOAT_EXPR:
+ return false;
+ case PLUS_EXPR:
+ case MINUS_EXPR:
+ case MULT_EXPR:
+ return !tree_expr_finite_p (TREE_OPERAND (x, 0))
+ || !tree_expr_finite_p (TREE_OPERAND (x, 1));
+ case ABS_EXPR:
+ case CONVERT_EXPR:
+ case NEGATE_EXPR:
+ case NON_LVALUE_EXPR:
+ case SAVE_EXPR:
+ return tree_expr_maybe_nan_p (TREE_OPERAND (x, 0));
+ case MIN_EXPR:
+ case MAX_EXPR:
+ return tree_expr_maybe_nan_p (TREE_OPERAND (x, 0))
+ || tree_expr_maybe_nan_p (TREE_OPERAND (x, 1));
+ case COND_EXPR:
+ return tree_expr_maybe_nan_p (TREE_OPERAND (x, 1))
+ || tree_expr_maybe_nan_p (TREE_OPERAND (x, 2));
+ case CALL_EXPR:
+ switch (get_call_combined_fn (x))
+ {
+ CASE_CFN_FABS:
+ return tree_expr_maybe_nan_p (CALL_EXPR_ARG (x, 0));
+ CASE_CFN_FMAX:
+ CASE_CFN_FMIN:
+ return tree_expr_maybe_nan_p (CALL_EXPR_ARG (x, 0))
+ || tree_expr_maybe_nan_p (CALL_EXPR_ARG (x, 1));
+ default:
+ return true;
+ }
+ default:
+ return true;
+ }
+}
+
#define tree_expr_nonnegative_warnv_p(X, Y) \
_Pragma ("GCC error \"Use RECURSE for recursive calls\"") 0
@@ -13878,7 +14120,13 @@ tree_binary_nonnegative_warnv_p (enum tree_code code, tree type, tree op0,
return false;
case BIT_AND_EXPR:
+ return RECURSE (op0) || RECURSE (op1);
+
case MAX_EXPR:
+ /* Usually RECURSE (op0) || RECURSE (op1) but NaNs complicate
+ things. */
+ if (tree_expr_maybe_nan_p (op0) || tree_expr_maybe_nan_p (op1))
+ return RECURSE (op0) && RECURSE (op1);
return RECURSE (op0) || RECURSE (op1);
case BIT_IOR_EXPR:
@@ -14038,8 +14286,18 @@ tree_call_nonnegative_warnv_p (tree type, combined_fn fn, tree arg0, tree arg1,
CASE_CFN_FMAX:
CASE_CFN_FMAX_FN:
- /* True if the 1st OR 2nd arguments are nonnegative. */
- return RECURSE (arg0) || RECURSE (arg1);
+ /* Usually RECURSE (arg0) || RECURSE (arg1) but NaNs complicate
+ things. In the presence of sNaNs, we're only guaranteed to be
+ non-negative if both operands are non-negative. In the presence
+ of qNaNs, we're non-negative if either operand is non-negative
+ and can't be a qNaN, or if both operands are non-negative. */
+ if (tree_expr_maybe_signaling_nan_p (arg0) ||
+ tree_expr_maybe_signaling_nan_p (arg1))
+ return RECURSE (arg0) && RECURSE (arg1);
+ return RECURSE (arg0) ? (!tree_expr_maybe_nan_p (arg0)
+ || RECURSE (arg1))
+ : (RECURSE (arg1)
+ && !tree_expr_maybe_nan_p (arg1));
CASE_CFN_FMIN:
CASE_CFN_FMIN_FN: