1/* LTO IL options.
2
3 Copyright (C) 2009-2023 Free Software Foundation, Inc.
4 Contributed by Simon Baldwin <simonb@google.com>
5
6This file is part of GCC.
7
8GCC is free software; you can redistribute it and/or modify it under
9the terms of the GNU General Public License as published by the Free
10Software Foundation; either version 3, or (at your option) any later
11version.
12
13GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14WARRANTY; without even the implied warranty of MERCHANTABILITY or
15FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16for more details.
17
18You should have received a copy of the GNU General Public License
19along with GCC; see the file COPYING3. If not see
20<http://www.gnu.org/licenses/>. */
21
22#include "config.h"
23#include "system.h"
24#include "coretypes.h"
25#include "backend.h"
26#include "target.h"
27#include "tree.h"
28#include "gimple.h"
29#include "cgraph.h"
30#include "lto-streamer.h"
31#include "opts.h"
32#include "toplev.h"
33
34/* Append the option piece OPT to the COLLECT_GCC_OPTIONS string
35 set up by OB, appropriately quoted and separated by spaces
36 (if !*FIRST_P). */
37
38static void
39append_to_collect_gcc_options (struct obstack *ob,
40 bool *first_p, const char *opt)
41{
42 const char *p, *q = opt;
43 if (!*first_p)
44 obstack_grow (ob, " ", 1);
45 obstack_grow (ob, "'", 1);
46 while ((p = strchr (s: q, c: '\'')))
47 {
48 obstack_grow (ob, q, p - q);
49 obstack_grow (ob, "'\\''", 4);
50 q = ++p;
51 }
52 obstack_grow (ob, q, strlen (q));
53 obstack_grow (ob, "'", 1);
54 *first_p = false;
55}
56
57/* Write currently held options to an LTO IL section. */
58
59void
60lto_write_options (void)
61{
62 char *section_name;
63 struct obstack temporary_obstack;
64 unsigned int i, j;
65 char *args;
66 bool first_p = true;
67
68 section_name = lto_get_section_name (LTO_section_opts, NULL, 0, NULL);
69 lto_begin_section (section_name, false);
70
71 obstack_init (&temporary_obstack);
72
73 if (!OPTION_SET_P (flag_openmp)
74 && !global_options.x_flag_openmp)
75 append_to_collect_gcc_options (ob: &temporary_obstack, first_p: &first_p,
76 opt: "-fno-openmp");
77 if (!OPTION_SET_P (flag_openacc)
78 && !global_options.x_flag_openacc)
79 append_to_collect_gcc_options (ob: &temporary_obstack, first_p: &first_p,
80 opt: "-fno-openacc");
81 /* Append PIC/PIE mode because its default depends on target and it is
82 subject of merging in lto-wrapper. */
83 if (!OPTION_SET_P (flag_pic) && !OPTION_SET_P (flag_pie))
84 {
85 append_to_collect_gcc_options (ob: &temporary_obstack, first_p: &first_p,
86 opt: global_options.x_flag_pic == 2
87 ? "-fPIC"
88 : global_options.x_flag_pic == 1
89 ? "-fpic"
90 : global_options.x_flag_pie == 2
91 ? "-fPIE"
92 : global_options.x_flag_pie == 1
93 ? "-fpie"
94 : "-fno-pie");
95 }
96
97 if (!OPTION_SET_P (flag_cf_protection))
98 {
99 append_to_collect_gcc_options (
100 ob: &temporary_obstack, first_p: &first_p,
101 opt: global_options.x_flag_cf_protection == CF_NONE
102 ? "-fcf-protection=none"
103 : global_options.x_flag_cf_protection == CF_FULL
104 ? "-fcf-protection=full"
105 : global_options.x_flag_cf_protection == CF_BRANCH
106 ? "-fcf-protection=branch"
107 : global_options.x_flag_cf_protection == CF_RETURN
108 ? "-fcf-protection=return"
109 : "");
110 }
111
112 /* If debug info is enabled append -g. */
113 if (debug_info_level > DINFO_LEVEL_NONE)
114 append_to_collect_gcc_options (ob: &temporary_obstack, first_p: &first_p, opt: "-g");
115
116 /* Append options from target hook and store them to offload_lto section. */
117 if (lto_stream_offload_p)
118 {
119 char *offload_opts = targetm.offload_options ();
120 char *offload_ptr = offload_opts;
121 while (offload_ptr)
122 {
123 char *next = strchr (s: offload_ptr, c: ' ');
124 if (next)
125 *next++ = '\0';
126 append_to_collect_gcc_options (ob: &temporary_obstack, first_p: &first_p,
127 opt: offload_ptr);
128 offload_ptr = next;
129 }
130 free (ptr: offload_opts);
131 }
132
133 /* Output explicitly passed options. */
134 for (i = 1; i < save_decoded_options_count; ++i)
135 {
136 struct cl_decoded_option *option = &save_decoded_options[i];
137
138 /* Skip explicitly some common options that we do not need. */
139 switch (option->opt_index)
140 {
141 case OPT_dumpbase:
142 case OPT_SPECIAL_unknown:
143 case OPT_SPECIAL_ignore:
144 case OPT_SPECIAL_warn_removed:
145 case OPT_SPECIAL_program_name:
146 case OPT_SPECIAL_input_file:
147 case OPT_dumpdir:
148 case OPT_fresolution_:
149 case OPT_fdebug_prefix_map_:
150 case OPT_ffile_prefix_map_:
151 case OPT_fmacro_prefix_map_:
152 case OPT_fprofile_prefix_map_:
153 case OPT_fcanon_prefix_map:
154 case OPT_fwhole_program:
155 continue;
156
157 default:
158 break;
159 }
160
161 /* Skip frontend and driver specific options here. */
162 if (!(cl_options[option->opt_index].flags & (CL_COMMON|CL_TARGET|CL_LTO)))
163 continue;
164
165 /* Do not store target-specific options in offload_lto section. */
166 if ((cl_options[option->opt_index].flags & CL_TARGET)
167 && lto_stream_offload_p)
168 continue;
169
170 /* Drop options created from the gcc driver that will be rejected
171 when passed on to the driver again. */
172 if (cl_options[option->opt_index].cl_reject_driver)
173 continue;
174
175 /* Also drop all options that are handled by the driver as well,
176 which includes things like -o and -v or -fhelp for example.
177 We do not need those. The only exception is -foffload option, if we
178 write it in offload_lto section. Also drop all diagnostic options. */
179 if ((cl_options[option->opt_index].flags & (CL_DRIVER|CL_WARNING))
180 && (!lto_stream_offload_p
181 || option->opt_index != OPT_foffload_options_))
182 continue;
183
184 for (j = 0; j < option->canonical_option_num_elements; ++j)
185 append_to_collect_gcc_options (ob: &temporary_obstack, first_p: &first_p,
186 opt: option->canonical_option[j]);
187 }
188
189 const char *collect_as_options = getenv (name: "COLLECT_AS_OPTIONS");
190 if (collect_as_options)
191 prepend_xassembler_to_collect_as_options (collect_as_options,
192 &temporary_obstack);
193
194 obstack_grow (&temporary_obstack, "\0", 1);
195 args = XOBFINISH (&temporary_obstack, char *);
196 lto_write_data (args, strlen (s: args) + 1);
197 lto_end_section ();
198
199 obstack_free (&temporary_obstack, NULL);
200 free (ptr: section_name);
201}
202

source code of gcc/lto-opts.cc