1038 lines
26 KiB
C
1038 lines
26 KiB
C
/* LTO plugin for gold and/or GNU ld.
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Copyright (C) 2009, 2010 Free Software Foundation, Inc.
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Contributed by Rafael Avila de Espindola (espindola@google.com).
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3, or (at your option)
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any later version.
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This program is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; see the file COPYING3. If not see
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<http://www.gnu.org/licenses/>. */
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/* The plugin has only one external function: onload. Gold passes it an array of
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function that the plugin uses to communicate back to gold.
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With the functions provided by gold, the plugin can be notified when
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gold first analyzes a file and pass a symbol table back to gold. The plugin
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is also notified when all symbols have been read and it is time to generate
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machine code for the necessary symbols.
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More information at http://gcc.gnu.org/wiki/whopr/driver.
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This plugin should be passed the lto-wrapper options and will forward them.
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It also has 2 options of its own:
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-debug: Print the command line used to run lto-wrapper.
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-nop: Instead of running lto-wrapper, pass the original to the plugin. This
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only works if the input files are hybrid. */
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#ifdef HAVE_CONFIG_H
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#include "config.h"
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#endif
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#if HAVE_STDINT_H
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#include <stdint.h>
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#endif
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#include <assert.h>
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#include <string.h>
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#include <stdlib.h>
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#include <stdio.h>
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#include <inttypes.h>
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#include <sys/stat.h>
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#include <unistd.h>
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#include <fcntl.h>
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#include <sys/types.h>
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#ifdef HAVE_SYS_WAIT_H
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#include <sys/wait.h>
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#endif
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#ifndef WIFEXITED
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#define WIFEXITED(S) (((S) & 0xff) == 0)
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#endif
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#ifndef WEXITSTATUS
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#define WEXITSTATUS(S) (((S) & 0xff00) >> 8)
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#endif
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#include <libiberty.h>
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#include <hashtab.h>
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#include "../gcc/lto/common.h"
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#include "simple-object.h"
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#include "plugin-api.h"
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/* Handle opening elf files on hosts, such as Windows, that may use
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text file handling that will break binary access. */
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#ifndef O_BINARY
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# define O_BINARY 0
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#endif
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/* Segment name for LTO sections. This is only used for Mach-O.
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FIXME: This needs to be kept in sync with darwin.c. */
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#define LTO_SEGMENT_NAME "__GNU_LTO"
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/* LTO magic section name. */
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#define LTO_SECTION_PREFIX ".gnu.lto_.symtab"
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#define LTO_SECTION_PREFIX_LEN (sizeof (LTO_SECTION_PREFIX) - 1)
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/* The part of the symbol table the plugin has to keep track of. Note that we
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must keep SYMS until all_symbols_read is called to give the linker time to
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copy the symbol information. */
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struct sym_aux
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{
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uint32_t slot;
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unsigned id;
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unsigned next_conflict;
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};
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struct plugin_symtab
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{
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int nsyms;
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struct sym_aux *aux;
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struct ld_plugin_symbol *syms;
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unsigned id;
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};
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/* Encapsulates object file data during symbol scan. */
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struct plugin_objfile
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{
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int found;
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simple_object_read *objfile;
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struct plugin_symtab *out;
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const struct ld_plugin_input_file *file;
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};
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/* All that we have to remember about a file. */
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struct plugin_file_info
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{
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char *name;
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void *handle;
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struct plugin_symtab symtab;
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struct plugin_symtab conflicts;
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};
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/* Until ASM_OUTPUT_LABELREF can be hookized and decoupled from
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stdio file streams, we do simple label translation here. */
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enum symbol_style
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{
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ss_none, /* No underscore prefix. */
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ss_win32, /* Underscore prefix any symbol not beginning with '@'. */
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ss_uscore, /* Underscore prefix all symbols. */
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};
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static char *arguments_file_name;
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static ld_plugin_register_claim_file register_claim_file;
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static ld_plugin_register_all_symbols_read register_all_symbols_read;
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static ld_plugin_get_symbols get_symbols;
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static ld_plugin_register_cleanup register_cleanup;
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static ld_plugin_add_input_file add_input_file;
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static ld_plugin_add_input_library add_input_library;
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static ld_plugin_message message;
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static ld_plugin_add_symbols add_symbols;
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static struct plugin_file_info *claimed_files = NULL;
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static unsigned int num_claimed_files = 0;
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static char **output_files = NULL;
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static unsigned int num_output_files = 0;
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static char **lto_wrapper_argv;
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static int lto_wrapper_num_args;
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static char **pass_through_items = NULL;
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static unsigned int num_pass_through_items;
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static char debug;
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static char nop;
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static char *resolution_file = NULL;
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/* The version of gold being used, or -1 if not gold. The number is
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MAJOR * 100 + MINOR. */
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static int gold_version = -1;
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/* Not used by default, but can be overridden at runtime
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by using -plugin-opt=-sym-style={none,win32,underscore|uscore}
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(in fact, only first letter of style arg is checked.) */
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static enum symbol_style sym_style = ss_none;
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static void
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check_1 (int gate, enum ld_plugin_level level, const char *text)
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{
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if (gate)
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return;
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if (message)
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message (level, text);
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else
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{
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/* If there is no nicer way to inform the user, fallback to stderr. */
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fprintf (stderr, "%s\n", text);
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if (level == LDPL_FATAL)
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abort ();
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}
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}
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/* This little wrapper allows check to be called with a non-integer
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first argument, such as a pointer that must be non-NULL. We can't
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use c99 bool type to coerce it into range, so we explicitly test. */
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#define check(GATE, LEVEL, TEXT) check_1 (((GATE) != 0), (LEVEL), (TEXT))
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/* Parse an entry of the IL symbol table. The data to be parsed is pointed
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by P and the result is written in ENTRY. The slot number is stored in SLOT.
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Returns the address of the next entry. */
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static char *
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parse_table_entry (char *p, struct ld_plugin_symbol *entry,
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struct sym_aux *aux)
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{
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unsigned char t;
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enum ld_plugin_symbol_kind translate_kind[] =
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{
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LDPK_DEF,
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LDPK_WEAKDEF,
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LDPK_UNDEF,
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LDPK_WEAKUNDEF,
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LDPK_COMMON
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};
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enum ld_plugin_symbol_visibility translate_visibility[] =
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{
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LDPV_DEFAULT,
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LDPV_PROTECTED,
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LDPV_INTERNAL,
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LDPV_HIDDEN
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};
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switch (sym_style)
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{
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case ss_win32:
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if (p[0] == '@')
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{
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/* cf. Duff's device. */
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case ss_none:
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entry->name = xstrdup (p);
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break;
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}
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/* FALL-THROUGH. */
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case ss_uscore:
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entry->name = concat ("_", p, NULL);
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break;
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default:
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check (0, LDPL_FATAL, "invalid symbol style requested");
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break;
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}
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while (*p)
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p++;
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p++;
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entry->version = NULL;
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entry->comdat_key = p;
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while (*p)
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p++;
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p++;
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if (strlen (entry->comdat_key) == 0)
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entry->comdat_key = NULL;
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else
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entry->comdat_key = xstrdup (entry->comdat_key);
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t = *p;
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check (t <= 4, LDPL_FATAL, "invalid symbol kind found");
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entry->def = translate_kind[t];
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p++;
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t = *p;
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check (t <= 3, LDPL_FATAL, "invalid symbol visibility found");
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entry->visibility = translate_visibility[t];
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p++;
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memcpy (&entry->size, p, sizeof (uint64_t));
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p += 8;
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memcpy (&aux->slot, p, sizeof (uint32_t));
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p += 4;
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entry->resolution = LDPR_UNKNOWN;
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aux->next_conflict = -1;
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return p;
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}
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/* Translate the IL symbol table located between DATA and END. Append the
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slots and symbols to OUT. */
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static void
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translate (char *data, char *end, struct plugin_symtab *out)
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{
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struct sym_aux *aux;
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struct ld_plugin_symbol *syms = NULL;
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int n, len;
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/* This overestimates the output buffer sizes, but at least
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the algorithm is O(1) now. */
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len = (end - data)/8 + out->nsyms + 1;
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syms = xrealloc (out->syms, len * sizeof (struct ld_plugin_symbol));
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aux = xrealloc (out->aux, len * sizeof (struct sym_aux));
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for (n = out->nsyms; data < end; n++)
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{
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aux[n].id = out->id;
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data = parse_table_entry (data, &syms[n], &aux[n]);
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}
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assert(n < len);
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out->nsyms = n;
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out->syms = syms;
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out->aux = aux;
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}
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/* Free all memory that is no longer needed after writing the symbol
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resolution. */
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static void
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free_1 (void)
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{
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unsigned int i;
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for (i = 0; i < num_claimed_files; i++)
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{
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struct plugin_file_info *info = &claimed_files[i];
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struct plugin_symtab *symtab = &info->symtab;
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unsigned int j;
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for (j = 0; j < symtab->nsyms; j++)
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{
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struct ld_plugin_symbol *s = &symtab->syms[j];
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free (s->name);
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if (s->comdat_key)
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free (s->comdat_key);
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}
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free (symtab->syms);
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symtab->syms = NULL;
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}
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}
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/* Free all remaining memory. */
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static void
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free_2 (void)
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{
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unsigned int i;
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for (i = 0; i < num_claimed_files; i++)
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{
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struct plugin_file_info *info = &claimed_files[i];
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struct plugin_symtab *symtab = &info->symtab;
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free (symtab->aux);
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free (info->name);
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}
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for (i = 0; i < num_output_files; i++)
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free (output_files[i]);
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free (output_files);
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free (claimed_files);
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claimed_files = NULL;
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num_claimed_files = 0;
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if (arguments_file_name)
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free (arguments_file_name);
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arguments_file_name = NULL;
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}
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/* Dump SYMTAB to resolution file F. */
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static void
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dump_symtab (FILE *f, struct plugin_symtab *symtab)
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{
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unsigned j;
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for (j = 0; j < symtab->nsyms; j++)
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{
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uint32_t slot = symtab->aux[j].slot;
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unsigned int resolution = symtab->syms[j].resolution;
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assert (resolution != LDPR_UNKNOWN);
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fprintf (f, "%u %x %s %s\n", (unsigned int) slot, symtab->aux[j].id,
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lto_resolution_str[resolution],
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symtab->syms[j].name);
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}
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}
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/* Finish the conflicts' resolution information after the linker resolved
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the original symbols */
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static void
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finish_conflict_resolution (struct plugin_symtab *symtab,
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struct plugin_symtab *conflicts)
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{
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int i, j;
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if (conflicts->nsyms == 0)
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return;
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for (i = 0; i < symtab->nsyms; i++)
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{
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int resolution = LDPR_UNKNOWN;
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if (symtab->aux[i].next_conflict == -1)
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continue;
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switch (symtab->syms[i].def)
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{
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case LDPK_DEF:
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case LDPK_COMMON: /* ??? */
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resolution = LDPR_RESOLVED_IR;
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break;
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case LDPK_WEAKDEF:
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resolution = LDPR_PREEMPTED_IR;
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break;
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case LDPK_UNDEF:
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case LDPK_WEAKUNDEF:
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resolution = symtab->syms[i].resolution;
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break;
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default:
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assert (0);
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}
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assert (resolution != LDPR_UNKNOWN);
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for (j = symtab->aux[i].next_conflict;
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j != -1;
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j = conflicts->aux[j].next_conflict)
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conflicts->syms[j].resolution = resolution;
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}
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}
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/* Free symbol table SYMTAB. */
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static void
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free_symtab (struct plugin_symtab *symtab)
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{
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free (symtab->syms);
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symtab->syms = NULL;
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free (symtab->aux);
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symtab->aux = NULL;
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}
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/* Writes the relocations to disk. */
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static void
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write_resolution (void)
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{
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unsigned int i;
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FILE *f;
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check (resolution_file, LDPL_FATAL, "resolution file not specified");
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f = fopen (resolution_file, "w");
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check (f, LDPL_FATAL, "could not open file");
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fprintf (f, "%d\n", num_claimed_files);
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for (i = 0; i < num_claimed_files; i++)
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{
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struct plugin_file_info *info = &claimed_files[i];
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struct plugin_symtab *symtab = &info->symtab;
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struct ld_plugin_symbol *syms = symtab->syms;
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get_symbols (info->handle, symtab->nsyms, syms);
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finish_conflict_resolution (symtab, &info->conflicts);
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fprintf (f, "%s %d\n", info->name, symtab->nsyms + info->conflicts.nsyms);
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dump_symtab (f, symtab);
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if (info->conflicts.nsyms)
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{
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dump_symtab (f, &info->conflicts);
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free_symtab (&info->conflicts);
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}
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}
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fclose (f);
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}
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/* Pass files generated by the lto-wrapper to the linker. FD is lto-wrapper's
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stdout. */
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static void
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add_output_files (FILE *f)
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{
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for (;;)
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{
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const unsigned piece = 32;
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char *buf, *s = xmalloc (piece);
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size_t len;
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buf = s;
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cont:
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if (!fgets (buf, piece, f))
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{
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free (s);
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break;
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}
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len = strlen (s);
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if (s[len - 1] != '\n')
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{
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s = xrealloc (s, len + piece);
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buf = s + len;
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goto cont;
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}
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s[len - 1] = '\0';
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num_output_files++;
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output_files
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= xrealloc (output_files, num_output_files * sizeof (char *));
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output_files[num_output_files - 1] = s;
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add_input_file (output_files[num_output_files - 1]);
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}
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}
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/* Execute the lto-wrapper. ARGV[0] is the binary. The rest of ARGV is the
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argument list. */
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static void
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exec_lto_wrapper (char *argv[])
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{
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int t, i;
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int status;
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char *at_args;
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FILE *args;
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FILE *wrapper_output;
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char *new_argv[3];
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struct pex_obj *pex;
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const char *errmsg;
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/* Write argv to a file to avoid a command line that is too long. */
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arguments_file_name = make_temp_file ("");
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check (arguments_file_name, LDPL_FATAL,
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"Failed to generate a temorary file name");
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args = fopen (arguments_file_name, "w");
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check (args, LDPL_FATAL, "could not open arguments file");
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t = writeargv (&argv[1], args);
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check (t == 0, LDPL_FATAL, "could not write arguments");
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t = fclose (args);
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check (t == 0, LDPL_FATAL, "could not close arguments file");
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at_args = concat ("@", arguments_file_name, NULL);
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check (at_args, LDPL_FATAL, "could not allocate");
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for (i = 1; argv[i]; i++)
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{
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char *a = argv[i];
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if (a[0] == '-' && a[1] == 'v' && a[2] == '\0')
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{
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for (i = 0; argv[i]; i++)
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fprintf (stderr, "%s ", argv[i]);
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fprintf (stderr, "\n");
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break;
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}
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}
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new_argv[0] = argv[0];
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new_argv[1] = at_args;
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new_argv[2] = NULL;
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if (debug)
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{
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for (i = 0; new_argv[i]; i++)
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fprintf (stderr, "%s ", new_argv[i]);
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fprintf (stderr, "\n");
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}
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pex = pex_init (PEX_USE_PIPES, "lto-wrapper", NULL);
|
|
check (pex != NULL, LDPL_FATAL, "could not pex_init lto-wrapper");
|
|
|
|
errmsg = pex_run (pex, 0, new_argv[0], new_argv, NULL, NULL, &t);
|
|
check (errmsg == NULL, LDPL_FATAL, "could not run lto-wrapper");
|
|
check (t == 0, LDPL_FATAL, "could not run lto-wrapper");
|
|
|
|
wrapper_output = pex_read_output (pex, 0);
|
|
check (wrapper_output, LDPL_FATAL, "could not read lto-wrapper output");
|
|
|
|
add_output_files (wrapper_output);
|
|
|
|
t = pex_get_status (pex, 1, &status);
|
|
check (t == 1, LDPL_FATAL, "could not get lto-wrapper exit status");
|
|
check (WIFEXITED (status) && WEXITSTATUS (status) == 0, LDPL_FATAL,
|
|
"lto-wrapper failed");
|
|
|
|
pex_free (pex);
|
|
|
|
free (at_args);
|
|
}
|
|
|
|
/* Pass the original files back to the linker. */
|
|
|
|
static void
|
|
use_original_files (void)
|
|
{
|
|
unsigned i;
|
|
for (i = 0; i < num_claimed_files; i++)
|
|
{
|
|
struct plugin_file_info *info = &claimed_files[i];
|
|
add_input_file (info->name);
|
|
}
|
|
}
|
|
|
|
|
|
/* Called by the linker once all symbols have been read. */
|
|
|
|
static enum ld_plugin_status
|
|
all_symbols_read_handler (void)
|
|
{
|
|
unsigned i;
|
|
unsigned num_lto_args = num_claimed_files + lto_wrapper_num_args + 1;
|
|
char **lto_argv;
|
|
const char **lto_arg_ptr;
|
|
if (num_claimed_files == 0)
|
|
return LDPS_OK;
|
|
|
|
if (nop)
|
|
{
|
|
use_original_files ();
|
|
return LDPS_OK;
|
|
}
|
|
|
|
lto_argv = (char **) xcalloc (sizeof (char *), num_lto_args);
|
|
lto_arg_ptr = (const char **) lto_argv;
|
|
assert (lto_wrapper_argv);
|
|
|
|
write_resolution ();
|
|
|
|
free_1 ();
|
|
|
|
for (i = 0; i < lto_wrapper_num_args; i++)
|
|
*lto_arg_ptr++ = lto_wrapper_argv[i];
|
|
|
|
for (i = 0; i < num_claimed_files; i++)
|
|
{
|
|
struct plugin_file_info *info = &claimed_files[i];
|
|
|
|
*lto_arg_ptr++ = info->name;
|
|
}
|
|
|
|
*lto_arg_ptr++ = NULL;
|
|
exec_lto_wrapper (lto_argv);
|
|
|
|
free (lto_argv);
|
|
|
|
/* --pass-through is not needed when using gold 1.11 or later. */
|
|
if (pass_through_items && gold_version < 111)
|
|
{
|
|
unsigned int i;
|
|
for (i = 0; i < num_pass_through_items; i++)
|
|
{
|
|
if (strncmp (pass_through_items[i], "-l", 2) == 0)
|
|
add_input_library (pass_through_items[i] + 2);
|
|
else
|
|
add_input_file (pass_through_items[i]);
|
|
free (pass_through_items[i]);
|
|
pass_through_items[i] = NULL;
|
|
}
|
|
free (pass_through_items);
|
|
pass_through_items = NULL;
|
|
}
|
|
|
|
return LDPS_OK;
|
|
}
|
|
|
|
/* Remove temporary files at the end of the link. */
|
|
|
|
static enum ld_plugin_status
|
|
cleanup_handler (void)
|
|
{
|
|
unsigned int i;
|
|
int t;
|
|
|
|
if (debug)
|
|
return LDPS_OK;
|
|
|
|
if (arguments_file_name)
|
|
{
|
|
t = unlink (arguments_file_name);
|
|
check (t == 0, LDPL_FATAL, "could not unlink arguments file");
|
|
}
|
|
|
|
for (i = 0; i < num_output_files; i++)
|
|
{
|
|
t = unlink (output_files[i]);
|
|
check (t == 0, LDPL_FATAL, "could not unlink output file");
|
|
}
|
|
|
|
free_2 ();
|
|
return LDPS_OK;
|
|
}
|
|
|
|
#define SWAP(type, a, b) \
|
|
do { type tmp_; tmp_ = (a); (a) = (b); (b) = tmp_; } while(0)
|
|
|
|
/* Compare two hash table entries */
|
|
|
|
static int eq_sym (const void *a, const void *b)
|
|
{
|
|
const struct ld_plugin_symbol *as = (const struct ld_plugin_symbol *)a;
|
|
const struct ld_plugin_symbol *bs = (const struct ld_plugin_symbol *)b;
|
|
|
|
return !strcmp (as->name, bs->name);
|
|
}
|
|
|
|
/* Hash a symbol */
|
|
|
|
static hashval_t hash_sym (const void *a)
|
|
{
|
|
const struct ld_plugin_symbol *as = (const struct ld_plugin_symbol *)a;
|
|
|
|
return htab_hash_string (as->name);
|
|
}
|
|
|
|
/* Determine how strong a symbol is */
|
|
|
|
static int symbol_strength (struct ld_plugin_symbol *s)
|
|
{
|
|
switch (s->def)
|
|
{
|
|
case LDPK_UNDEF:
|
|
case LDPK_WEAKUNDEF:
|
|
return 0;
|
|
case LDPK_WEAKDEF:
|
|
return 1;
|
|
default:
|
|
return 2;
|
|
}
|
|
}
|
|
|
|
/* In the ld -r case we can get dups in the LTO symbol tables, where
|
|
the same symbol can have different resolutions (e.g. undefined and defined).
|
|
|
|
We have to keep that in the LTO symbol tables, but the dups confuse
|
|
gold and then finally gcc by supplying incorrect resolutions.
|
|
|
|
Problem is that the main gold symbol table doesn't know about subids
|
|
and does not distingush the same symbols in different states.
|
|
|
|
So we drop duplicates from the linker visible symbol table
|
|
and keep them in a private table. Then later do own symbol
|
|
resolution for the duplicated based on the results for the
|
|
originals.
|
|
|
|
Then when writing out the resolution file readd the dropped symbols.
|
|
|
|
XXX how to handle common? */
|
|
|
|
static void
|
|
resolve_conflicts (struct plugin_symtab *t, struct plugin_symtab *conflicts)
|
|
{
|
|
htab_t symtab = htab_create (t->nsyms, hash_sym, eq_sym, NULL);
|
|
int i;
|
|
int out;
|
|
int outlen;
|
|
|
|
outlen = t->nsyms;
|
|
conflicts->syms = xmalloc (sizeof (struct ld_plugin_symbol) * outlen);
|
|
conflicts->aux = xmalloc (sizeof (struct sym_aux) * outlen);
|
|
|
|
/* Move all duplicate symbols into the auxillary conflicts table. */
|
|
out = 0;
|
|
for (i = 0; i < t->nsyms; i++)
|
|
{
|
|
struct ld_plugin_symbol *s = &t->syms[i];
|
|
struct sym_aux *aux = &t->aux[i];
|
|
void **slot;
|
|
|
|
slot = htab_find_slot (symtab, s, INSERT);
|
|
if (*slot != NULL)
|
|
{
|
|
int cnf;
|
|
struct ld_plugin_symbol *orig = (struct ld_plugin_symbol *)*slot;
|
|
struct sym_aux *orig_aux = &t->aux[orig - t->syms];
|
|
|
|
/* Always let the linker resolve the strongest symbol */
|
|
if (symbol_strength (orig) < symbol_strength (s))
|
|
{
|
|
SWAP (struct ld_plugin_symbol, *orig, *s);
|
|
SWAP (uint32_t, orig_aux->slot, aux->slot);
|
|
SWAP (unsigned, orig_aux->id, aux->id);
|
|
/* Don't swap conflict chain pointer */
|
|
}
|
|
|
|
/* Move current symbol into the conflicts table */
|
|
cnf = conflicts->nsyms++;
|
|
conflicts->syms[cnf] = *s;
|
|
conflicts->aux[cnf] = *aux;
|
|
aux = &conflicts->aux[cnf];
|
|
|
|
/* Update conflicts chain of the original symbol */
|
|
aux->next_conflict = orig_aux->next_conflict;
|
|
orig_aux->next_conflict = cnf;
|
|
|
|
continue;
|
|
}
|
|
|
|
/* Remove previous duplicates in the main table */
|
|
if (out < i)
|
|
{
|
|
t->syms[out] = *s;
|
|
t->aux[out] = *aux;
|
|
}
|
|
|
|
/* Put original into the hash table */
|
|
*slot = &t->syms[out];
|
|
out++;
|
|
}
|
|
|
|
assert (conflicts->nsyms <= outlen);
|
|
assert (conflicts->nsyms + out == t->nsyms);
|
|
|
|
t->nsyms = out;
|
|
htab_delete (symtab);
|
|
}
|
|
|
|
/* Process one section of an object file. */
|
|
|
|
static int
|
|
process_symtab (void *data, const char *name, off_t offset, off_t length)
|
|
{
|
|
struct plugin_objfile *obj = (struct plugin_objfile *)data;
|
|
char *s;
|
|
char *secdata;
|
|
|
|
if (strncmp (name, LTO_SECTION_PREFIX, LTO_SECTION_PREFIX_LEN) != 0)
|
|
return 1;
|
|
|
|
s = strrchr (name, '.');
|
|
if (s)
|
|
sscanf (s, ".%x", &obj->out->id);
|
|
secdata = xmalloc (length);
|
|
offset += obj->file->offset;
|
|
if (offset != lseek (obj->file->fd, offset, SEEK_SET)
|
|
|| length != read (obj->file->fd, secdata, length))
|
|
{
|
|
if (message)
|
|
message (LDPL_FATAL, "%s: corrupt object file", obj->file->name);
|
|
/* Force claim_file_handler to abandon this file. */
|
|
obj->found = 0;
|
|
free (secdata);
|
|
return 0;
|
|
}
|
|
|
|
translate (secdata, secdata + length, obj->out);
|
|
obj->found++;
|
|
free (secdata);
|
|
return 1;
|
|
}
|
|
|
|
/* Callback used by gold to check if the plugin will claim FILE. Writes
|
|
the result in CLAIMED. */
|
|
|
|
static enum ld_plugin_status
|
|
claim_file_handler (const struct ld_plugin_input_file *file, int *claimed)
|
|
{
|
|
enum ld_plugin_status status;
|
|
struct plugin_objfile obj;
|
|
struct plugin_file_info lto_file;
|
|
int err;
|
|
const char *errmsg;
|
|
|
|
memset (<o_file, 0, sizeof (struct plugin_file_info));
|
|
|
|
if (file->offset != 0)
|
|
{
|
|
char *objname;
|
|
/* We pass the offset of the actual file, not the archive header.
|
|
Can't use PRIx64, because that's C99, so we have to print the
|
|
64-bit hex int as two 32-bit ones. */
|
|
int lo, hi;
|
|
lo = file->offset & 0xffffffff;
|
|
hi = ((int64_t)file->offset >> 32) & 0xffffffff;
|
|
int t = hi ? asprintf (&objname, "%s@0x%x%08x", file->name, lo, hi)
|
|
: asprintf (&objname, "%s@0x%x", file->name, lo);
|
|
check (t >= 0, LDPL_FATAL, "asprintf failed");
|
|
lto_file.name = objname;
|
|
}
|
|
else
|
|
{
|
|
lto_file.name = xstrdup (file->name);
|
|
}
|
|
lto_file.handle = file->handle;
|
|
|
|
*claimed = 0;
|
|
obj.file = file;
|
|
obj.found = 0;
|
|
obj.out = <o_file.symtab;
|
|
errmsg = NULL;
|
|
obj.objfile = simple_object_start_read (file->fd, file->offset, LTO_SEGMENT_NAME,
|
|
&errmsg, &err);
|
|
/* No file, but also no error code means unrecognized format; just skip it. */
|
|
if (!obj.objfile && !err)
|
|
goto err;
|
|
|
|
if (obj.objfile)
|
|
errmsg = simple_object_find_sections (obj.objfile, process_symtab, &obj, &err);
|
|
|
|
if (!obj.objfile || errmsg)
|
|
{
|
|
if (err && message)
|
|
message (LDPL_FATAL, "%s: %s: %s", file->name, errmsg,
|
|
xstrerror (err));
|
|
else if (message)
|
|
message (LDPL_FATAL, "%s: %s", file->name, errmsg);
|
|
goto err;
|
|
}
|
|
|
|
if (obj.found == 0)
|
|
goto err;
|
|
|
|
if (obj.found > 1)
|
|
resolve_conflicts (<o_file.symtab, <o_file.conflicts);
|
|
|
|
status = add_symbols (file->handle, lto_file.symtab.nsyms,
|
|
lto_file.symtab.syms);
|
|
check (status == LDPS_OK, LDPL_FATAL, "could not add symbols");
|
|
|
|
*claimed = 1;
|
|
num_claimed_files++;
|
|
claimed_files =
|
|
xrealloc (claimed_files,
|
|
num_claimed_files * sizeof (struct plugin_file_info));
|
|
claimed_files[num_claimed_files - 1] = lto_file;
|
|
|
|
goto cleanup;
|
|
|
|
err:
|
|
free (lto_file.name);
|
|
|
|
cleanup:
|
|
if (obj.objfile)
|
|
simple_object_release_read (obj.objfile);
|
|
|
|
return LDPS_OK;
|
|
}
|
|
|
|
/* Parse the plugin options. */
|
|
|
|
static void
|
|
process_option (const char *option)
|
|
{
|
|
if (strcmp (option, "-debug") == 0)
|
|
debug = 1;
|
|
else if (strcmp (option, "-nop") == 0)
|
|
nop = 1;
|
|
else if (!strncmp (option, "-pass-through=", strlen("-pass-through=")))
|
|
{
|
|
num_pass_through_items++;
|
|
pass_through_items = xrealloc (pass_through_items,
|
|
num_pass_through_items * sizeof (char *));
|
|
pass_through_items[num_pass_through_items - 1] =
|
|
xstrdup (option + strlen ("-pass-through="));
|
|
}
|
|
else if (!strncmp (option, "-sym-style=", sizeof ("-sym-style=") - 1))
|
|
{
|
|
switch (option[sizeof ("-sym-style=") - 1])
|
|
{
|
|
case 'w':
|
|
sym_style = ss_win32;
|
|
break;
|
|
case 'u':
|
|
sym_style = ss_uscore;
|
|
break;
|
|
default:
|
|
sym_style = ss_none;
|
|
break;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
int size;
|
|
char *opt = xstrdup (option);
|
|
lto_wrapper_num_args += 1;
|
|
size = lto_wrapper_num_args * sizeof (char *);
|
|
lto_wrapper_argv = (char **) xrealloc (lto_wrapper_argv, size);
|
|
lto_wrapper_argv[lto_wrapper_num_args - 1] = opt;
|
|
if (strncmp (option, "-fresolution=", sizeof ("-fresolution=") - 1) == 0)
|
|
resolution_file = opt + sizeof ("-fresolution=") - 1;
|
|
}
|
|
}
|
|
|
|
/* Called by gold after loading the plugin. TV is the transfer vector. */
|
|
|
|
enum ld_plugin_status
|
|
onload (struct ld_plugin_tv *tv)
|
|
{
|
|
struct ld_plugin_tv *p;
|
|
enum ld_plugin_status status;
|
|
|
|
p = tv;
|
|
while (p->tv_tag)
|
|
{
|
|
switch (p->tv_tag)
|
|
{
|
|
case LDPT_MESSAGE:
|
|
message = p->tv_u.tv_message;
|
|
break;
|
|
case LDPT_REGISTER_CLAIM_FILE_HOOK:
|
|
register_claim_file = p->tv_u.tv_register_claim_file;
|
|
break;
|
|
case LDPT_ADD_SYMBOLS:
|
|
add_symbols = p->tv_u.tv_add_symbols;
|
|
break;
|
|
case LDPT_REGISTER_ALL_SYMBOLS_READ_HOOK:
|
|
register_all_symbols_read = p->tv_u.tv_register_all_symbols_read;
|
|
break;
|
|
case LDPT_GET_SYMBOLS:
|
|
get_symbols = p->tv_u.tv_get_symbols;
|
|
break;
|
|
case LDPT_REGISTER_CLEANUP_HOOK:
|
|
register_cleanup = p->tv_u.tv_register_cleanup;
|
|
break;
|
|
case LDPT_ADD_INPUT_FILE:
|
|
add_input_file = p->tv_u.tv_add_input_file;
|
|
break;
|
|
case LDPT_ADD_INPUT_LIBRARY:
|
|
add_input_library = p->tv_u.tv_add_input_library;
|
|
break;
|
|
case LDPT_OPTION:
|
|
process_option (p->tv_u.tv_string);
|
|
break;
|
|
case LDPT_GOLD_VERSION:
|
|
gold_version = p->tv_u.tv_val;
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
p++;
|
|
}
|
|
|
|
check (register_claim_file, LDPL_FATAL, "register_claim_file not found");
|
|
check (add_symbols, LDPL_FATAL, "add_symbols not found");
|
|
status = register_claim_file (claim_file_handler);
|
|
check (status == LDPS_OK, LDPL_FATAL,
|
|
"could not register the claim_file callback");
|
|
|
|
if (register_cleanup)
|
|
{
|
|
status = register_cleanup (cleanup_handler);
|
|
check (status == LDPS_OK, LDPL_FATAL,
|
|
"could not register the cleanup callback");
|
|
}
|
|
|
|
if (register_all_symbols_read)
|
|
{
|
|
check (get_symbols, LDPL_FATAL, "get_symbols not found");
|
|
status = register_all_symbols_read (all_symbols_read_handler);
|
|
check (status == LDPS_OK, LDPL_FATAL,
|
|
"could not register the all_symbols_read callback");
|
|
}
|
|
|
|
return LDPS_OK;
|
|
}
|