tree-ssa-forwprop.c (forward_propagate_into_cond): For combining both operands require either both have single uses or combining...

2007-10-12  Richard Guenther <rguenther@suse.de>

	* tree-ssa-forwprop.c (forward_propagate_into_cond): For
	combining both operands require either both have single uses
	or combining to a constant.

From-SVN: r129261
This commit is contained in:
Richard Guenther 2007-10-12 14:21:43 +00:00 committed by Richard Biener
parent a2085738a9
commit 7cd13c1cad
2 changed files with 12 additions and 6 deletions

View File

@ -1,3 +1,9 @@
2007-10-12 Richard Guenther <rguenther@suse.de>
* tree-ssa-forwprop.c (forward_propagate_into_cond): For
combining both operands require either both have single uses
or combining to a constant.
2007-10-12 Richard Guenther <rguenther@suse.de>
PR middle-end/26198

View File

@ -360,7 +360,7 @@ forward_propagate_into_cond (tree cond_expr, tree stmt)
tree tmp = NULL_TREE;
tree cond = COND_EXPR_COND (cond_expr);
tree name, def_stmt, rhs0 = NULL_TREE, rhs1 = NULL_TREE;
bool single_use_p;
bool single_use0_p = false, single_use1_p = false;
/* We can do tree combining on SSA_NAME and comparison expressions. */
if (COMPARISON_CLASS_P (cond)
@ -369,7 +369,7 @@ forward_propagate_into_cond (tree cond_expr, tree stmt)
/* For comparisons use the first operand, that is likely to
simplify comparisons against constants. */
name = TREE_OPERAND (cond, 0);
def_stmt = get_prop_source_stmt (name, false, &single_use_p);
def_stmt = get_prop_source_stmt (name, false, &single_use0_p);
if (def_stmt != NULL_TREE
&& can_propagate_from (def_stmt))
{
@ -377,7 +377,7 @@ forward_propagate_into_cond (tree cond_expr, tree stmt)
rhs0 = GIMPLE_STMT_OPERAND (def_stmt, 1);
tmp = combine_cond_expr_cond (TREE_CODE (cond), boolean_type_node,
fold_convert (TREE_TYPE (op1), rhs0),
op1, !single_use_p);
op1, !single_use0_p);
}
/* If that wasn't successful, try the second operand. */
if (tmp == NULL_TREE
@ -385,7 +385,7 @@ forward_propagate_into_cond (tree cond_expr, tree stmt)
{
tree op0 = TREE_OPERAND (cond, 0);
name = TREE_OPERAND (cond, 1);
def_stmt = get_prop_source_stmt (name, false, &single_use_p);
def_stmt = get_prop_source_stmt (name, false, &single_use1_p);
if (def_stmt == NULL_TREE
|| !can_propagate_from (def_stmt))
return did_something;
@ -394,7 +394,7 @@ forward_propagate_into_cond (tree cond_expr, tree stmt)
tmp = combine_cond_expr_cond (TREE_CODE (cond), boolean_type_node,
op0,
fold_convert (TREE_TYPE (op0), rhs1),
!single_use_p);
!single_use1_p);
}
/* If that wasn't successful either, try both operands. */
if (tmp == NULL_TREE
@ -403,7 +403,7 @@ forward_propagate_into_cond (tree cond_expr, tree stmt)
tmp = combine_cond_expr_cond (TREE_CODE (cond), boolean_type_node,
rhs0,
fold_convert (TREE_TYPE (rhs0), rhs1),
!single_use_p);
!(single_use0_p && single_use1_p));
}
else if (TREE_CODE (cond) == SSA_NAME)
{