by the C-based front ends. The structure of gimplified, or
language-independent, trees is dictated by the grammar described in this
file.
- Copyright (C) 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
+ Copyright (C) 2002, 2003, 2004, 2005, 2007 Free Software Foundation, Inc.
Lowering of expressions contributed by Sebastian Pop <s.pop@laposte.net>
Re-written to support lowering of whole function trees, documentation
and miscellaneous cleanups by Diego Novillo <dnovillo@redhat.com>
GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
-Software Foundation; either version 2, or (at your option) any later
+Software Foundation; either version 3, or (at your option) any later
version.
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
for more details.
You should have received a copy of the GNU General Public License
-along with GCC; see the file COPYING. If not, write to the Free
-Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
-02110-1301, USA. */
+along with GCC; see the file COPYING3. If not see
+<http://www.gnu.org/licenses/>. */
#include "config.h"
#include "system.h"
return GS_OK;
}
+/* Optimize embedded COMPOUND_LITERAL_EXPRs within a CONSTRUCTOR,
+ return a new CONSTRUCTOR if something changed. */
+
+static tree
+optimize_compound_literals_in_ctor (tree orig_ctor)
+{
+ tree ctor = orig_ctor;
+ VEC(constructor_elt,gc) *elts = CONSTRUCTOR_ELTS (ctor);
+ unsigned int idx, num = VEC_length (constructor_elt, elts);
+
+ for (idx = 0; idx < num; idx++)
+ {
+ tree value = VEC_index (constructor_elt, elts, idx)->value;
+ tree newval = value;
+ if (TREE_CODE (value) == CONSTRUCTOR)
+ newval = optimize_compound_literals_in_ctor (value);
+ else if (TREE_CODE (value) == COMPOUND_LITERAL_EXPR)
+ {
+ tree decl_s = COMPOUND_LITERAL_EXPR_DECL_STMT (value);
+ tree decl = DECL_EXPR_DECL (decl_s);
+ tree init = DECL_INITIAL (decl);
+
+ if (!TREE_ADDRESSABLE (value)
+ && !TREE_ADDRESSABLE (decl)
+ && init)
+ newval = init;
+ }
+ if (newval == value)
+ continue;
+
+ if (ctor == orig_ctor)
+ {
+ ctor = copy_node (orig_ctor);
+ CONSTRUCTOR_ELTS (ctor) = VEC_copy (constructor_elt, gc, elts);
+ elts = CONSTRUCTOR_ELTS (ctor);
+ }
+ VEC_index (constructor_elt, elts, idx)->value = newval;
+ }
+ return ctor;
+}
+
/* Do C-specific gimplification. Args are as for gimplify_expr. */
int
case COMPOUND_LITERAL_EXPR:
return gimplify_compound_literal_expr (expr_p, pre_p);
+ case INIT_EXPR:
+ case MODIFY_EXPR:
+ if (TREE_CODE (TREE_OPERAND (*expr_p, 1)) == COMPOUND_LITERAL_EXPR)
+ {
+ tree complit = TREE_OPERAND (*expr_p, 1);
+ tree decl_s = COMPOUND_LITERAL_EXPR_DECL_STMT (complit);
+ tree decl = DECL_EXPR_DECL (decl_s);
+ tree init = DECL_INITIAL (decl);
+
+ /* struct T x = (struct T) { 0, 1, 2 } can be optimized
+ into struct T x = { 0, 1, 2 } if the address of the
+ compound literal has never been taken. */
+ if (!TREE_ADDRESSABLE (complit)
+ && !TREE_ADDRESSABLE (decl)
+ && init)
+ {
+ *expr_p = copy_node (*expr_p);
+ TREE_OPERAND (*expr_p, 1) = init;
+ return GS_OK;
+ }
+ }
+ else if (TREE_CODE (TREE_OPERAND (*expr_p, 1)) == CONSTRUCTOR)
+ {
+ tree ctor
+ = optimize_compound_literals_in_ctor (TREE_OPERAND (*expr_p, 1));
+
+ if (ctor != TREE_OPERAND (*expr_p, 1))
+ {
+ *expr_p = copy_node (*expr_p);
+ TREE_OPERAND (*expr_p, 1) = ctor;
+ return GS_OK;
+ }
+ }
+ return GS_UNHANDLED;
+
default:
return GS_UNHANDLED;
}