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
26 #ifndef FIRM_LOWER_CALLS_H
27 #define FIRM_LOWER_CALLS_H
29 #include "firm_types.h"
32 * Additional flags for the lowering.
34 typedef enum compound_call_lowering_flags {
35 LF_NONE = 0, /**< no additional flags */
36 LF_RETURN_HIDDEN = 1 << 0, /**< return the hidden address instead of void */
37 } compound_call_lowering_flags;
38 ENUM_BITSET(compound_call_lowering_flags)
41 * Lower calls with compound parameter and return types.
42 * This function does the following transformations:
44 * If LF_COMPOUND_PARAM is set:
46 * - Copy compound parameters to a new location on the callers
47 * stack and transmit the address of this new location
49 * If LF_COMPOUND_RETURN is set:
51 * - Adds a new (hidden) pointer parameter for
52 * any return compound type. The return type is replaced by void
53 * or if LOWERING_FLAGS_RETURN_HIDDEN is set by the address.
55 * - Use of the hidden parameters in the function code.
57 * - Change all calls to functions with compound return
58 * by providing space for the hidden parameter on the callers
61 * - Replace a possible block copy after the function call.
65 * - Changes the types of methods and calls to the lowered ones
67 * - lower all method types of existing entities
69 * In pseudo-code, the following transformation is done:
72 struct x ret = func(a, b);
81 * If the function returns only one possible result, the copy-on-return
82 * optimization is done, ie.
94 void func(struct x *ret, a) {
99 void lower_calls_with_compounds(compound_call_lowering_flags flags);