aboutsummaryrefslogtreecommitdiff
path: root/gold/main.cc
blob: 7de1b8779dc96a17c17ef5e6d846b5b9a28d5241 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
// main.cc -- gold main function.

// Copyright 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
// Written by Ian Lance Taylor <iant@google.com>.

// This file is part of gold.

// This program 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 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
// MA 02110-1301, USA.

#include "gold.h"

#include <cstdio>
#include <cstring>

#ifdef HAVE_MALLINFO
#include <malloc.h>
#endif

#include "libiberty.h"

#include "script.h"
#include "options.h"
#include "parameters.h"
#include "errors.h"
#include "mapfile.h"
#include "dirsearch.h"
#include "workqueue.h"
#include "object.h"
#include "archive.h"
#include "symtab.h"
#include "layout.h"
#include "plugin.h"
#include "gc.h"
#include "icf.h"
#include "incremental.h"
#include "timer.h"

using namespace gold;

// This function emits the commandline to a hard-coded file in temp.
// This is useful for debugging since ld is typically invoked by gcc,
// so its commandline is not always easy to extract.  You should be
// able to run 'gcc -B... foo.o -o foo' to invoke this linker the
// first time, and then /tmp/ld-run-foo.sh to invoke it on subsequent
// runes.  "/tmp/ld-run-foo.sh debug" will run the linker inside gdb
// (or whatever value the environment variable GDB is set to), for
// even easier debugging.  Since this is a debugging-only tool, and
// creates files, it is only turned on when the user explicitly asks
// for it, by compiling with -DDEBUG.  Do not do this for release
// versions of the linker!

#ifdef DEBUG
#include <stdio.h>
#include <sys/stat.h>    // for chmod()

static std::string
collect_argv(int argc, char** argv)
{
  // This is used by write_debug_script(), which wants the unedited argv.
  std::string args;
  for (int i = 0; i < argc; ++i)
    {
      args.append(" '");
      // Now append argv[i], but with all single-quotes escaped
      const char* argpos = argv[i];
      while (1)
        {
          const int len = strcspn(argpos, "'");
          args.append(argpos, len);
          if (argpos[len] == '\0')
            break;
          args.append("'\"'\"'");
          argpos += len + 1;
        }
      args.append("'");
    }
  return args;
}

static void
write_debug_script(std::string filename_str,
		   const char* argv_0, const char* args)
{
  size_t slash = filename_str.rfind('/');
  if (slash != std::string::npos)
    filename_str = filename_str.c_str() + slash + 1;
  filename_str = std::string("/tmp/ld-run-") + filename_str + ".sh";
  const char* filename = filename_str.c_str();
  FILE* fp = fopen(filename, "w");
  if (fp)
    {
      fprintf(fp, "[ \"$1\" = debug ]"
              " && PREFIX=\"${GDB-gdb} --annotate=3 --fullname %s --args\""
              " && shift\n",
              argv_0);
      fprintf(fp, "$PREFIX%s $*\n", args);
      fclose(fp);
      chmod(filename, 0755);
    }
  else
    filename = "[none]";
  fprintf(stderr, "Welcome to gold!  Commandline written to %s.\n", filename);
  fflush(stderr);
}

#else // !defined(DEBUG)

static inline std::string
collect_argv(int, char**)
{
  return "";
}

static inline void
write_debug_script(std::string, const char*, const char*)
{
}

#endif // !defined(DEBUG)


int
main(int argc, char** argv)
{
#if defined (HAVE_SETLOCALE) && defined (HAVE_LC_MESSAGES)
  setlocale(LC_MESSAGES, "");
#endif
#if defined (HAVE_SETLOCALE)
  setlocale(LC_CTYPE, "");
#endif
  bindtextdomain(PACKAGE, LOCALEDIR);
  textdomain(PACKAGE);

  program_name = argv[0];

  // In libiberty; expands @filename to the args in "filename".
  expandargv(&argc, &argv);

  // This is used by write_debug_script(), which wants the unedited argv.
  std::string args = collect_argv(argc, argv);

  Errors errors(program_name);

  // Initialize the global parameters, to let random code get to the
  // errors object.
  set_parameters_errors(&errors);

  // Handle the command line options.
  Command_line command_line;
  command_line.process(argc - 1, const_cast<const char**>(argv + 1));

  Timer timer;
  if (command_line.options().stats())
    timer.start();

  // Store some options in the globally accessible parameters.
  set_parameters_options(&command_line.options());

  // Do this as early as possible (since it prints a welcome message).
  write_debug_script(command_line.options().output_file_name(),
                     program_name, args.c_str());

  // If the user asked for a map file, open it.
  Mapfile* mapfile = NULL;
  if (command_line.options().user_set_Map())
    {
      mapfile = new Mapfile();
      if (!mapfile->open(command_line.options().Map()))
	{
	  delete mapfile;
	  mapfile = NULL;
	}
    }

  // The GNU linker ignores version scripts when generating
  // relocatable output.  If we are not compatible, then we break the
  // Linux kernel build, which uses a linker script with -r which must
  // not force symbols to be local.  It would actually be useful to
  // permit symbols to be forced local with -r, though, as it would
  // permit some linker optimizations.  Perhaps we need yet another
  // option to control this.  FIXME.
  if (parameters->options().relocatable())
    command_line.script_options().version_script_info()->clear();

  // Load plugin libraries.
  if (command_line.options().has_plugins())
    command_line.options().plugins()->load_plugins();

  // The work queue.
  Workqueue workqueue(command_line.options());

  // The list of input objects.
  Input_objects input_objects;

  // The Garbage Collection (GC, --gc-sections) Object.
  Garbage_collection gc;

  // The Identical Code Folding (ICF, --icf) Object.
  Icf icf;

  // The symbol table.  We're going to guess here how many symbols
  // we're going to see based on the number of input files.  Even when
  // this is off, it means at worst we don't quite optimize hashtable
  // resizing as well as we could have (perhaps using more memory).
  Symbol_table symtab(command_line.number_of_input_files() * 1024,
                      command_line.version_script());

  if (parameters->options().gc_sections())
    symtab.set_gc(&gc);

  if (parameters->options().icf_enabled())
    symtab.set_icf(&icf);

  // The layout object.
  Layout layout(command_line.number_of_input_files(),
		&command_line.script_options());

  if (layout.incremental_inputs() != NULL)
    layout.incremental_inputs()->report_command_line(argc, argv);

  if (parameters->options().section_ordering_file())
    layout.read_layout_from_file();

  // Get the search path from the -L options.
  Dirsearch search_path;
  search_path.initialize(&workqueue, &command_line.options().library_path());

  // Queue up the first set of tasks.
  queue_initial_tasks(command_line.options(), search_path,
		      command_line, &workqueue, &input_objects,
		      &symtab, &layout, mapfile);

  // Run the main task processing loop.
  workqueue.process(0);

  if (command_line.options().stats())
    {
      Timer::TimeStats elapsed = timer.get_elapsed_time();
      fprintf(stderr,
             _("%s: total run time: " \
               "(user: %ld.%06ld sys: %ld.%06ld wall: %ld.%06ld)\n"),
              program_name,
              elapsed.user / 1000, (elapsed.user % 1000) * 1000,
              elapsed.sys / 1000, (elapsed.sys % 1000) * 1000,
              elapsed.wall / 1000, (elapsed.wall % 1000) * 1000);

#ifdef HAVE_MALLINFO
      struct mallinfo m = mallinfo();
      fprintf(stderr, _("%s: total space allocated by malloc: %d bytes\n"),
	      program_name, m.arena);
#endif
      File_read::print_stats();
      Archive::print_stats();
      Lib_group::print_stats();
      fprintf(stderr, _("%s: output file size: %lld bytes\n"),
	      program_name, static_cast<long long>(layout.output_file_size()));
      symtab.print_stats();
      layout.print_stats();
      Free_list::print_stats();
    }

  // Issue defined symbol report.
  if (command_line.options().user_set_print_symbol_counts())
    input_objects.print_symbol_counts(&symtab);

  // Output cross reference table.
  if (command_line.options().cref())
    input_objects.print_cref(&symtab,
			     mapfile == NULL ? stdout : mapfile->file());

  if (mapfile != NULL)
    mapfile->close();

  if (parameters->options().fatal_warnings()
      && errors.warning_count() > 0
      && errors.error_count() == 0)
    gold_error("treating warnings as errors");

  // If the user used --noinhibit-exec, we force the exit status to be
  // successful.  This is compatible with GNU ld.
  gold_exit((errors.error_count() == 0
	     || parameters->options().noinhibit_exec())
	    ? GOLD_OK
	    : GOLD_ERR);
}