1/*
2 * Copyright (c) 2017-2021 The Khronos Group Inc.
3 * Copyright (c) 2017-2021 Valve Corporation
4 * Copyright (c) 2017-2021 LunarG, Inc.
5 * Copyright (c) 2021 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
6 *
7 * Licensed under the Apache License, Version 2.0 (the "License");
8 * you may not use this file except in compliance with the License.
9 * You may obtain a copy of the License at
10 *
11 *     http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing, software
14 * distributed under the License is distributed on an "AS IS" BASIS,
15 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 * See the License for the specific language governing permissions and
17 * limitations under the License.
18 *
19 * Author: Lenny Komow <lenny@lunarg.com>
20 * Author: Charles Giessen <charles@lunarg.com>
21 */
22
23// This code generates an assembly file which provides offsets to get struct members from assembly code.
24
25// __USE_MINGW_ANSI_STDIO is needed to use the %zu format specifier with mingw-w64.
26// Otherwise the compiler will complain about an unknown format specifier.
27#if defined(__MINGW32__) && !defined(__USE_MINGW_ANSI_STDIO)
28#define __USE_MINGW_ANSI_STDIO 1
29#endif
30
31#include <stdio.h>
32#include "loader_common.h"
33#include "log.h"
34
35#if defined(__GNUC__) || defined(__clang__)
36void produce_asm_define() {
37    // GCC and clang make it easy to print easy to regex for values
38    __asm__("# VULKAN_LOADER_ERROR_BIT = %c0" : : "i"(VULKAN_LOADER_ERROR_BIT));
39    __asm__("# PTR_SIZE = %c0" : : "i"(sizeof(void *)));
40    __asm__("# CHAR_PTR_SIZE = %c0" : : "i"(sizeof(char *)));
41    __asm__("# FUNCTION_OFFSET_INSTANCE = %c0" : : "i"(offsetof(struct loader_instance, phys_dev_ext_disp_functions)));
42    __asm__("# PHYS_DEV_OFFSET_INST_DISPATCH = %c0" : : "i"(offsetof(struct loader_instance_dispatch_table, phys_dev_ext)));
43    __asm__("# PHYS_DEV_OFFSET_PHYS_DEV_TRAMP = %c0" : : "i"(offsetof(struct loader_physical_device_tramp, phys_dev)));
44    __asm__("# ICD_TERM_OFFSET_PHYS_DEV_TERM = %c0" : : "i"(offsetof(struct loader_physical_device_term, this_icd_term)));
45    __asm__("# PHYS_DEV_OFFSET_PHYS_DEV_TERM = %c0" : : "i"(offsetof(struct loader_physical_device_term, phys_dev)));
46    __asm__("# INSTANCE_OFFSET_ICD_TERM = %c0" : : "i"(offsetof(struct loader_icd_term, this_instance)));
47    __asm__("# DISPATCH_OFFSET_ICD_TERM = %c0" : : "i"(offsetof(struct loader_icd_term, phys_dev_ext)));
48    __asm__("# EXT_OFFSET_DEVICE_DISPATCH = %c0" : : "i"(offsetof(struct loader_dev_dispatch_table, ext_dispatch)));
49}
50#elif defined(_WIN32)
51// MSVC will print the name of the value and the value in hex
52// Must disable optimization for this translation unit, otherwise the compiler strips out the variables
53static const uint32_t PTR_SIZE = sizeof(void *);
54static const uint32_t CHAR_PTR_SIZE = sizeof(char *);
55static const uint32_t FUNCTION_OFFSET_INSTANCE = offsetof(struct loader_instance, phys_dev_ext_disp_functions);
56static const uint32_t PHYS_DEV_OFFSET_INST_DISPATCH = offsetof(struct loader_instance_dispatch_table, phys_dev_ext);
57static const uint32_t PHYS_DEV_OFFSET_PHYS_DEV_TRAMP = offsetof(struct loader_physical_device_tramp, phys_dev);
58static const uint32_t ICD_TERM_OFFSET_PHYS_DEV_TERM = offsetof(struct loader_physical_device_term, this_icd_term);
59static const uint32_t PHYS_DEV_OFFSET_PHYS_DEV_TERM = offsetof(struct loader_physical_device_term, phys_dev);
60static const uint32_t INSTANCE_OFFSET_ICD_TERM = offsetof(struct loader_icd_term, this_instance);
61static const uint32_t DISPATCH_OFFSET_ICD_TERM = offsetof(struct loader_icd_term, phys_dev_ext);
62static const uint32_t EXT_OFFSET_DEVICE_DISPATCH = offsetof(struct loader_dev_dispatch_table, ext_dispatch);
63#else
64#warning asm_offset.c variable declarations need to be defined for this platform
65#endif
66
67#if !defined(_MSC_VER) || (_MSC_VER >= 1900)
68#define SIZE_T_FMT "%-8zu"
69#elif defined(__GNUC__) || defined(__clang__)
70#define SIZE_T_FMT "%-8lu"
71#else
72#warning asm_offset.c SIZE_T_FMT must be defined for this platform
73#endif
74
75struct ValueInfo {
76    const char *name;
77    size_t value;
78    const char *comment;
79};
80
81// This file can both be executed to produce gen_defines.asm and contains all the relevant data which
82// the parse_asm_values.py script needs to write gen_defines.asm, necessary for cross compilation
83int main(int argc, char **argv) {
84    const char *assembler = NULL;
85    for (int i = 0; i < argc; ++i) {
86        if (!strcmp(argv[i], "MASM")) {
87            assembler = "MASM";
88        } else if (!strcmp(argv[i], "GAS")) {
89            assembler = "GAS";
90        }
91    }
92    if (assembler == NULL) {
93        return 1;
94    }
95
96    struct ValueInfo values[] = {
97        // clang-format off
98        { .name = "VULKAN_LOADER_ERROR_BIT", .value = (size_t) VULKAN_LOADER_ERROR_BIT,
99            .comment = "The numerical value of the enum value 'VULKAN_LOADER_ERROR_BIT'" },
100        { .name = "PTR_SIZE", .value = sizeof(void*),
101            .comment = "The size of a pointer" },
102        { .name = "CHAR_PTR_SIZE", .value = sizeof(char *),
103            .comment = "The size of a 'const char *' struct" },
104        { .name = "FUNCTION_OFFSET_INSTANCE", .value = offsetof(struct loader_instance, phys_dev_ext_disp_functions),
105            .comment = "The offset of 'phys_dev_ext_disp_functions' within a 'loader_instance' struct" },
106        { .name = "PHYS_DEV_OFFSET_INST_DISPATCH", .value = offsetof(struct loader_instance_dispatch_table, phys_dev_ext),
107            .comment = "The offset of 'phys_dev_ext' within in 'loader_instance_dispatch_table' struct" },
108        { .name = "PHYS_DEV_OFFSET_PHYS_DEV_TRAMP", .value = offsetof(struct loader_physical_device_tramp, phys_dev),
109            .comment = "The offset of 'phys_dev' within a 'loader_physical_device_tramp' struct" },
110        { .name = "ICD_TERM_OFFSET_PHYS_DEV_TERM", .value = offsetof(struct loader_physical_device_term, this_icd_term),
111            .comment = "The offset of 'this_icd_term' within a 'loader_physical_device_term' struct" },
112        { .name = "PHYS_DEV_OFFSET_PHYS_DEV_TERM", .value = offsetof(struct loader_physical_device_term, phys_dev),
113            .comment = "The offset of 'phys_dev' within a 'loader_physical_device_term' struct" },
114        { .name = "INSTANCE_OFFSET_ICD_TERM", .value = offsetof(struct loader_icd_term, this_instance),
115            .comment = "The offset of 'this_instance' within a 'loader_icd_term' struct" },
116        { .name = "DISPATCH_OFFSET_ICD_TERM", .value = offsetof(struct loader_icd_term, phys_dev_ext),
117            .comment = "The offset of 'phys_dev_ext' within a 'loader_icd_term' struct" },
118        { .name = "EXT_OFFSET_DEVICE_DISPATCH", .value = offsetof(struct loader_dev_dispatch_table, ext_dispatch),
119            .comment = "The offset of 'ext_dispatch' within a 'loader_dev_dispatch_table' struct" },
120        // clang-format on
121    };
122
123    FILE *file = loader_fopen("gen_defines.asm", "w");
124    fprintf(file, "\n");
125    if (!strcmp(assembler, "MASM")) {
126        for (size_t i = 0; i < sizeof(values) / sizeof(values[0]); ++i) {
127            fprintf(file, "%-32s equ " SIZE_T_FMT "; %s\n", values[i].name, values[i].value, values[i].comment);
128        }
129    } else if (!strcmp(assembler, "GAS")) {
130#if defined(__x86_64__) || defined(__i386__)
131        const char *comment_delimiter = "#";
132#if defined(__x86_64__)
133        fprintf(file, ".set X86_64, 1\n");
134#endif  // defined(__x86_64__)
135#elif defined(__aarch64__)
136        const char *comment_delimiter = "//";
137        fprintf(file, ".set AARCH_64, 1\n");
138#else
139        // Default comment delimiter
140        const char *comment_delimiter = "#";
141#endif
142        for (size_t i = 0; i < sizeof(values) / sizeof(values[0]); ++i) {
143            fprintf(file, ".set %-32s, " SIZE_T_FMT "%s %s\n", values[i].name, values[i].value, comment_delimiter,
144                    values[i].comment);
145        }
146    }
147    return fclose(file);
148}
149