appropriately sign-extended or truncated. */
t = force_fit_type_double (type, TREE_INT_CST_LOW (arg1),
TREE_INT_CST_HIGH (arg1),
- /* Don't set the overflow when
- converting from a pointer, */
- !POINTER_TYPE_P (TREE_TYPE (arg1))
- /* or to a sizetype with same signedness
- and the precision is unchanged.
- ??? sizetype is always sign-extended,
- but its signedness depends on the
- frontend. Thus we see spurious overflows
- here if we do not check this. */
- && !((TYPE_PRECISION (TREE_TYPE (arg1))
- == TYPE_PRECISION (type))
- && (TYPE_UNSIGNED (TREE_TYPE (arg1))
- == TYPE_UNSIGNED (type))
- && ((TREE_CODE (TREE_TYPE (arg1)) == INTEGER_TYPE
- && TYPE_IS_SIZETYPE (TREE_TYPE (arg1)))
- || (TREE_CODE (type) == INTEGER_TYPE
- && TYPE_IS_SIZETYPE (type)))),
+ !POINTER_TYPE_P (TREE_TYPE (arg1)),
(TREE_INT_CST_HIGH (arg1) < 0
&& (TYPE_UNSIGNED (type)
< TYPE_UNSIGNED (TREE_TYPE (arg1))))
tree lhs = NULL_TREE;
tree rhs = NULL_TREE;
- /* This transformation is only worthwhile if we don't have to wrap
- arg in a SAVE_EXPR, and the operation can be simplified on at least
- one of the branches once its pushed inside the COND_EXPR. */
- if (!TREE_CONSTANT (arg))
- return NULL_TREE;
-
if (TREE_CODE (cond) == COND_EXPR)
{
test = TREE_OPERAND (cond, 0);
false_value = constant_boolean_node (false, testtype);
}
+ /* This transformation is only worthwhile if we don't have to wrap ARG
+ in a SAVE_EXPR and the operation can be simplified on at least one
+ of the branches once its pushed inside the COND_EXPR. */
+ if (!TREE_CONSTANT (arg)
+ && (TREE_SIDE_EFFECTS (arg)
+ || TREE_CONSTANT (true_value) || TREE_CONSTANT (false_value)))
+ return NULL_TREE;
+
arg = fold_convert_loc (loc, arg_type, arg);
if (lhs == 0)
{
rhs = fold_build2_loc (loc, code, type, arg, false_value);
}
- test = fold_build3_loc (loc, COND_EXPR, type, test, lhs, rhs);
- return fold_convert_loc (loc, type, test);
+ /* Check that we have simplified at least one of the branches. */
+ if (!TREE_CONSTANT (arg) && !TREE_CONSTANT (lhs) && !TREE_CONSTANT (rhs))
+ return NULL_TREE;
+
+ return fold_build3_loc (loc, COND_EXPR, type, test, lhs, rhs);
}
\f
var1 = split_tree (arg1, code, &con1, &lit1, &minus_lit1,
code == MINUS_EXPR);
- /* With undefined overflow we can only associate constants
- with one variable. */
- if (((POINTER_TYPE_P (type) && POINTER_TYPE_OVERFLOW_UNDEFINED)
- || (INTEGRAL_TYPE_P (type) && !TYPE_OVERFLOW_WRAPS (type)))
- && var0 && var1)
+ /* Recombine MINUS_EXPR operands by using PLUS_EXPR. */
+ if (code == MINUS_EXPR)
+ code = PLUS_EXPR;
+
+ /* With undefined overflow we can only associate constants with one
+ variable, and constants whose association doesn't overflow. */
+ if ((POINTER_TYPE_P (type) && POINTER_TYPE_OVERFLOW_UNDEFINED)
+ || (INTEGRAL_TYPE_P (type) && !TYPE_OVERFLOW_WRAPS (type)))
{
- tree tmp0 = var0;
- tree tmp1 = var1;
-
- if (TREE_CODE (tmp0) == NEGATE_EXPR)
- tmp0 = TREE_OPERAND (tmp0, 0);
- if (TREE_CODE (tmp1) == NEGATE_EXPR)
- tmp1 = TREE_OPERAND (tmp1, 0);
- /* The only case we can still associate with two variables
- is if they are the same, modulo negation. */
- if (!operand_equal_p (tmp0, tmp1, 0))
- ok = false;
+ if (var0 && var1)
+ {
+ tree tmp0 = var0;
+ tree tmp1 = var1;
+
+ if (TREE_CODE (tmp0) == NEGATE_EXPR)
+ tmp0 = TREE_OPERAND (tmp0, 0);
+ if (TREE_CODE (tmp1) == NEGATE_EXPR)
+ tmp1 = TREE_OPERAND (tmp1, 0);
+ /* The only case we can still associate with two variables
+ is if they are the same, modulo negation. */
+ if (!operand_equal_p (tmp0, tmp1, 0))
+ ok = false;
+ }
+
+ if (ok && lit0 && lit1)
+ {
+ tree tmp0 = fold_convert (type, lit0);
+ tree tmp1 = fold_convert (type, lit1);
+
+ if (!TREE_OVERFLOW (tmp0) && !TREE_OVERFLOW (tmp1)
+ && TREE_OVERFLOW (fold_build2 (code, type, tmp0, tmp1)))
+ ok = false;
+ }
}
/* Only do something if we found more than two objects. Otherwise,
+ (lit0 != 0) + (lit1 != 0)
+ (minus_lit0 != 0) + (minus_lit1 != 0))))
{
- /* Recombine MINUS_EXPR operands by using PLUS_EXPR. */
- if (code == MINUS_EXPR)
- code = PLUS_EXPR;
-
var0 = associate_trees (loc, var0, var1, code, type);
con0 = associate_trees (loc, con0, con1, code, type);
lit0 = associate_trees (loc, lit0, lit1, code, type);
&& TREE_INT_CST_HIGH (arg1) == -1)
return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
- /* Optimize TRUNC_MOD_EXPR by a power of two into a BIT_AND_EXPR,
- i.e. "X % C" into "X & (C - 1)", if X and C are positive. */
- strict_overflow_p = false;
- if ((code == TRUNC_MOD_EXPR || code == FLOOR_MOD_EXPR)
- && (TYPE_UNSIGNED (type)
- || tree_expr_nonnegative_warnv_p (op0, &strict_overflow_p)))
- {
- tree c = arg1;
- /* Also optimize A % (C << N) where C is a power of 2,
- to A & ((C << N) - 1). */
- if (TREE_CODE (arg1) == LSHIFT_EXPR)
- c = TREE_OPERAND (arg1, 0);
-
- if (integer_pow2p (c) && tree_int_cst_sgn (c) > 0)
- {
- tree mask = fold_build2_loc (loc, MINUS_EXPR, TREE_TYPE (arg1), arg1,
- build_int_cst (TREE_TYPE (arg1), 1));
- if (strict_overflow_p)
- fold_overflow_warning (("assuming signed overflow does not "
- "occur when simplifying "
- "X % (power of two)"),
- WARN_STRICT_OVERFLOW_MISC);
- return fold_build2_loc (loc, BIT_AND_EXPR, type,
- fold_convert_loc (loc, type, arg0),
- fold_convert_loc (loc, type, mask));
- }
- }
-
/* X % -C is the same as X % C. */
if (code == TRUNC_MOD_EXPR
&& !TYPE_UNSIGNED (type)
fold_convert_loc (loc, type,
TREE_OPERAND (arg1, 0)));
+ strict_overflow_p = false;
if (TREE_CODE (arg1) == INTEGER_CST
&& 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
&strict_overflow_p)))
return fold_convert_loc (loc, type, tem);
}
+ /* Optimize TRUNC_MOD_EXPR by a power of two into a BIT_AND_EXPR,
+ i.e. "X % C" into "X & (C - 1)", if X and C are positive. */
+ if ((code == TRUNC_MOD_EXPR || code == FLOOR_MOD_EXPR)
+ && (TYPE_UNSIGNED (type)
+ || tree_expr_nonnegative_warnv_p (op0, &strict_overflow_p)))
+ {
+ tree c = arg1;
+ /* Also optimize A % (C << N) where C is a power of 2,
+ to A & ((C << N) - 1). */
+ if (TREE_CODE (arg1) == LSHIFT_EXPR)
+ c = TREE_OPERAND (arg1, 0);
+
+ if (integer_pow2p (c) && tree_int_cst_sgn (c) > 0)
+ {
+ tree mask
+ = fold_build2_loc (loc, MINUS_EXPR, TREE_TYPE (arg1), arg1,
+ build_int_cst (TREE_TYPE (arg1), 1));
+ if (strict_overflow_p)
+ fold_overflow_warning (("assuming signed overflow does not "
+ "occur when simplifying "
+ "X % (power of two)"),
+ WARN_STRICT_OVERFLOW_MISC);
+ return fold_build2_loc (loc, BIT_AND_EXPR, type,
+ fold_convert_loc (loc, type, arg0),
+ fold_convert_loc (loc, type, mask));
+ }
+ }
+
return NULL_TREE;
case LROTATE_EXPR:
case SAVE_EXPR:
return multiple_of_p (type, TREE_OPERAND (top, 0), bottom);
+ case COND_EXPR:
+ return (multiple_of_p (type, TREE_OPERAND (top, 1), bottom)
+ && multiple_of_p (type, TREE_OPERAND (top, 2), bottom));
+
case INTEGER_CST:
if (TREE_CODE (bottom) != INTEGER_CST
|| integer_zerop (bottom)
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