+2005-05-27 Richard Guenther <rguenth@gcc.gnu.org>
+
+ * tree-inline.c (copy_body_r): Manually fold *& to deal
+ with ADDR_EXPRs with mismatched types for now.
+
+ * gimplify.c (fold_indirect_ref_rhs): New function.
+ (gimplify_modify_expr_rhs): Use it instead of pessimistic
+ fold_indirect_ref.
+
+ * fold-const.c (fold_indirect_ref_1): Add type argument;
+ make sure the resulting expression is of this type.
+ (build_fold_indirect_ref, fold_indirect_ref): Adjust callers.
+
2005-05-27 Kazu Hirata <kazu@cs.umass.edu>
PR tree-optimization/21658
return build_fold_addr_expr_with_type (t, build_pointer_type (TREE_TYPE (t)));
}
-/* Given a pointer value T, return a simplified version of an indirection
- through T, or NULL_TREE if no simplification is possible. */
+/* Given a pointer value OP0 and a type TYPE, return a simplified version
+ of an indirection through OP0, or NULL_TREE if no simplification is
+ possible. */
static tree
-fold_indirect_ref_1 (tree t)
+fold_indirect_ref_1 (tree type, tree op0)
{
- tree type = TREE_TYPE (TREE_TYPE (t));
- tree sub = t;
+ tree sub = op0;
tree subtype;
STRIP_NOPS (sub);
tree op = TREE_OPERAND (sub, 0);
tree optype = TREE_TYPE (op);
/* *&p => p */
- if (lang_hooks.types_compatible_p (type, optype))
+ if (type == optype)
return op;
/* *(foo *)&fooarray => fooarray[0] */
else if (TREE_CODE (optype) == ARRAY_TYPE
- && lang_hooks.types_compatible_p (type, TREE_TYPE (optype)))
+ && type == TREE_TYPE (optype))
{
tree type_domain = TYPE_DOMAIN (optype);
tree min_val = size_zero_node;
/* *(foo *)fooarrptr => (*fooarrptr)[0] */
if (TREE_CODE (TREE_TYPE (subtype)) == ARRAY_TYPE
- && lang_hooks.types_compatible_p (type, TREE_TYPE (TREE_TYPE (subtype))))
+ && type == TREE_TYPE (TREE_TYPE (subtype)))
{
tree type_domain;
tree min_val = size_zero_node;
tree
build_fold_indirect_ref (tree t)
{
- tree sub = fold_indirect_ref_1 (t);
+ tree type = TREE_TYPE (TREE_TYPE (t));
+ tree sub = fold_indirect_ref_1 (type, t);
if (sub)
return sub;
else
- return build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (t)), t);
+ return build1 (INDIRECT_REF, type, t);
}
/* Given an INDIRECT_REF T, return either T or a simplified version. */
tree
fold_indirect_ref (tree t)
{
- tree sub = fold_indirect_ref_1 (TREE_OPERAND (t, 0));
+ tree sub = fold_indirect_ref_1 (TREE_TYPE (t), TREE_OPERAND (t, 0));
if (sub)
return sub;
return GS_ALL_DONE;
}
+/* Given a pointer value OP0, return a simplified version of an
+ indirection through OP0, or NULL_TREE if no simplification is
+ possible. This may only be applied to a rhs of an expression.
+ Note that the resulting type may be different from the type pointed
+ to in the sense that it is still compatible from the langhooks
+ point of view. */
+
+static tree
+fold_indirect_ref_rhs (tree t)
+{
+ tree type = TREE_TYPE (TREE_TYPE (t));
+ tree sub = t;
+ tree subtype;
+
+ STRIP_NOPS (sub);
+ subtype = TREE_TYPE (sub);
+ if (!POINTER_TYPE_P (subtype))
+ return NULL_TREE;
+
+ if (TREE_CODE (sub) == ADDR_EXPR)
+ {
+ tree op = TREE_OPERAND (sub, 0);
+ tree optype = TREE_TYPE (op);
+ /* *&p => p */
+ if (lang_hooks.types_compatible_p (type, optype))
+ return op;
+ /* *(foo *)&fooarray => fooarray[0] */
+ else if (TREE_CODE (optype) == ARRAY_TYPE
+ && lang_hooks.types_compatible_p (type, TREE_TYPE (optype)))
+ {
+ tree type_domain = TYPE_DOMAIN (optype);
+ tree min_val = size_zero_node;
+ if (type_domain && TYPE_MIN_VALUE (type_domain))
+ min_val = TYPE_MIN_VALUE (type_domain);
+ return build4 (ARRAY_REF, type, op, min_val, NULL_TREE, NULL_TREE);
+ }
+ }
+
+ /* *(foo *)fooarrptr => (*fooarrptr)[0] */
+ if (TREE_CODE (TREE_TYPE (subtype)) == ARRAY_TYPE
+ && lang_hooks.types_compatible_p (type, TREE_TYPE (TREE_TYPE (subtype))))
+ {
+ tree type_domain;
+ tree min_val = size_zero_node;
+ sub = fold_indirect_ref_rhs (sub);
+ if (! sub)
+ sub = build1 (INDIRECT_REF, TREE_TYPE (subtype), sub);
+ type_domain = TYPE_DOMAIN (TREE_TYPE (sub));
+ if (type_domain && TYPE_MIN_VALUE (type_domain))
+ min_val = TYPE_MIN_VALUE (type_domain);
+ return build4 (ARRAY_REF, type, sub, min_val, NULL_TREE, NULL_TREE);
+ }
+
+ return NULL_TREE;
+}
+
/* Subroutine of gimplify_modify_expr to do simplifications of MODIFY_EXPRs
based on the code of the RHS. We loop for as long as something changes. */
This kind of code arises in C++ when an object is bound
to a const reference, and if "x" is a TARGET_EXPR we want
to take advantage of the optimization below. */
- tree t = fold_indirect_ref (*from_p);
- if (t != *from_p)
+ tree t = fold_indirect_ref_rhs (TREE_OPERAND (*from_p, 0));
+ if (t)
{
*from_p = t;
ret = GS_OK;
n = splay_tree_lookup (id->decl_map, (splay_tree_key) decl);
if (n)
{
- *tp = build_fold_indirect_ref ((tree)n->value);
+ /* If we happen to get an ADDR_EXPR in n->value, strip
+ it manually here as we'll eventually get ADDR_EXPRs
+ which lie about their types pointed to. In this case
+ build_fold_indirect_ref wouldn't strip the INDIRECT_REF,
+ but we absolutely rely on that. */
+ if (TREE_CODE ((tree)n->value) == ADDR_EXPR)
+ *tp = TREE_OPERAND ((tree)n->value, 0);
+ else
+ *tp = build1 (INDIRECT_REF,
+ TREE_TYPE (TREE_TYPE ((tree)n->value)),
+ (tree)n->value);
*walk_subtrees = 0;
return NULL;
}