2 * Copyright (C) 1995-2011 University of Karlsruhe. All right reserved.
4 * This file is part of libFirm.
6 * This file may be distributed and/or modified under the terms of the
7 * GNU General Public License version 2 as published by the Free Software
8 * Foundation and appearing in the file LICENSE.GPL included in the
9 * packaging of this file.
11 * Licensees holding valid libFirm Professional Edition licenses may use
12 * this file in accordance with the libFirm Commercial License.
13 * Agreement provided with the Software.
15 * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
16 * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * @brief Lowering of calls with compound arguments
23 * @author Michael Beck
25 #ifndef FIRM_LOWER_CALLS_H
26 #define FIRM_LOWER_CALLS_H
28 #include "firm_types.h"
31 * Additional flags for the lowering.
33 typedef enum compound_call_lowering_flags {
34 LF_NONE = 0, /**< no additional flags */
35 LF_RETURN_HIDDEN = 1 << 0, /**< return the hidden address instead of void */
36 LF_DONT_LOWER_ARGUMENTS = 1 << 1, /**< don't lower compound call arguments
37 (some backends can handle them themselves) */
38 } compound_call_lowering_flags;
39 ENUM_BITSET(compound_call_lowering_flags)
42 * Lower calls with compound parameter and return types.
43 * This function does the following transformations:
45 * If LF_COMPOUND_PARAM is set:
47 * - Copy compound parameters to a new location on the callers
48 * stack and transmit the address of this new location
50 * If LF_COMPOUND_RETURN is set:
52 * - Adds a new (hidden) pointer parameter for
53 * any return compound type. The return type is replaced by void
54 * or if LOWERING_FLAGS_RETURN_HIDDEN is set by the address.
56 * - Use of the hidden parameters in the function code.
58 * - Change all calls to functions with compound return
59 * by providing space for the hidden parameter on the callers
62 * - Replace a possible block copy after the function call.
66 * - Changes the types of methods and calls to the lowered ones
68 * - lower all method types of existing entities
70 * In pseudo-code, the following transformation is done:
73 struct x ret = func(a, b);
82 * If the function returns only one possible result, the copy-on-return
83 * optimization is done, ie.
95 void func(struct x *ret, a) {
100 void lower_calls_with_compounds(compound_call_lowering_flags flags);