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Diffstat (limited to 'gas/dwarf2dbg.c')
| -rw-r--r-- | gas/dwarf2dbg.c | 769 |
1 files changed, 0 insertions, 769 deletions
diff --git a/gas/dwarf2dbg.c b/gas/dwarf2dbg.c deleted file mode 100644 index e735592e737..00000000000 --- a/gas/dwarf2dbg.c +++ /dev/null @@ -1,769 +0,0 @@ -/* dwarf2dbg.c - DWARF2 debug support - Copyright (C) 1999 Free Software Foundation, Inc. - Contributed by David Mosberger-Tang <davidm@hpl.hp.com> - - This file is part of GAS, the GNU Assembler. - - GAS 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 2, or (at your option) - any later version. - - GAS 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 GAS; see the file COPYING. If not, write to the Free - Software Foundation, 59 Temple Place - Suite 330, Boston, MA - 02111-1307, USA. */ - -/* Logical line numbers can be controlled by the compiler via the - following two directives: - - .file FILENO "file.c" - .loc FILENO LINENO [COLUMN] - - FILENO is the filenumber. */ - -#include "ansidecl.h" - -#include "as.h" -#include "dwarf2dbg.h" -#include "subsegs.h" - -#include "elf/dwarf2.h" - -/* Since we can't generate the prolog until the body is complete, we - use three different subsegments for .debug_line: one holding the - prolog, one for the directory and filename info, and one for the - body ("statement program"). */ -#define DL_PROLOG 0 -#define DL_FILES 1 -#define DL_BODY 2 - -/* First special line opcde - leave room for the standard opcodes. - Note: If you want to change this, you'll have to update the - "standard_opcode_lengths" table that is emitted below in - dwarf2_finish(). */ -#define DWARF2_LINE_OPCODE_BASE 10 - -#ifndef DWARF2_LINE_BASE - /* Minimum line offset in a special line info. opcode. This value - was chosen to give a reasonable range of values. */ -# define DWARF2_LINE_BASE -5 -#endif - -/* Range of line offsets in a special line info. opcode. */ -#ifndef DWARF2_LINE_RANGE -# define DWARF2_LINE_RANGE 14 -#endif - -#ifndef DWARF2_LINE_MIN_INSN_LENGTH - /* Define the architecture-dependent minimum instruction length (in - bytes). This value should be rather too small than too big. */ -# define DWARF2_LINE_MIN_INSN_LENGTH 4 -#endif - -/* Flag that indicates the initial value of the is_stmt_start flag. - In the present implementation, we do not mark any lines as - the beginning of a source statement, because that information - is not made available by the GCC front-end. */ -#define DWARF2_LINE_DEFAULT_IS_STMT 1 - -/* Flag that indicates the initial value of the is_stmt_start flag. - In the present implementation, we do not mark any lines as - the beginning of a source statement, because that information - is not made available by the GCC front-end. */ -#define DWARF2_LINE_DEFAULT_IS_STMT 1 - -/* Given a special op, return the line skip amount. */ -#define SPECIAL_LINE(op) \ - (((op) - DWARF2_LINE_OPCODE_BASE)%DWARF2_LINE_RANGE + DWARF2_LINE_BASE) - -/* Given a special op, return the address skip amount (in units of - DWARF2_LINE_MIN_INSN_LENGTH. */ -#define SPECIAL_ADDR(op) (((op) - DWARF2_LINE_OPCODE_BASE)/DWARF2_LINE_RANGE) - -/* The maximum address skip amount that can be encoded with a special op. */ -#define MAX_SPECIAL_ADDR_DELTA SPECIAL_ADDR(255) - -#define INITIAL_STATE \ - /* Initialize as per DWARF2.0 standard. */ \ - 0, /* address */ \ - 1, /* file */ \ - 1, /* line */ \ - 0, /* column */ \ - DWARF2_LINE_DEFAULT_IS_STMT, /* is_stmt */ \ - 0, /* basic_block */ \ - 1 /* empty_sequence */ - -static struct - { - /* state machine state as per DWARF2 manual: */ - struct dwarf2_sm - { - addressT addr; - unsigned int filenum; - unsigned int line; - unsigned int column; - unsigned int - is_stmt : 1, - basic_block : 1, - empty_sequence : 1; /* current code sequence has no DWARF2 directives? */ - } - sm; - - unsigned int - any_dwarf2_directives : 1; /* did we emit any DWARF2 line debug directives? */ - - fragS * frag; /* frag that "addr" is relative to */ - segT text_seg; /* text segment "addr" is relative to */ - subsegT text_subseg; - segT line_seg; /* ".debug_line" segment */ - int last_filename; /* index of last filename that was used */ - int num_filenames; /* index of last filename in use */ - int filename_len; /* length of the filename array */ - struct - { - int dir; /* valid after gen_dir_list() only */ - char *name; /* full path before gen_dir_list(), filename afterwards */ - } - *file; - - struct dwarf2_line_info current; /* current source info: */ - - /* counters for statistical purposes: */ - unsigned int num_line_entries; - unsigned int opcode_hist[256]; /* histogram of opcode frequencies */ - } -ls = - { - { - INITIAL_STATE - }, - 0, - 0, - 0, - 0, - 0, - 0, - 0, - 0, - NULL, - { NULL, 0, 0, 0, 0 }, - 0, - { - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 - } - }; - - -/* Function prototypes: */ -static void out_uleb128 PARAMS ((addressT)); -static void out_sleb128 PARAMS ((offsetT)); -static void gen_addr_line PARAMS ((int, addressT)); -static void reset_state_machine PARAMS ((void)); -static void out_set_addr PARAMS ((addressT)); -static void out_end_sequence PARAMS ((void)); -static int get_filenum PARAMS ((int, char *)); -static void gen_dir_list PARAMS ((void)); -static void gen_file_list PARAMS ((void)); -static void print_stats PARAMS ((unsigned long)); - - -#define out_byte(byte) FRAG_APPEND_1_CHAR(byte) -#define out_opcode(opc) (out_byte ((opc)), ++ls.opcode_hist[(opc) & 0xff]) - -/* Output an unsigned "little-endian base 128" number. */ -static void -out_uleb128 (value) - addressT value; -{ - unsigned char byte, more = 0x80; - - do - { - byte = value & 0x7f; - value >>= 7; - if (value == 0) - more = 0; - out_byte (more | byte); - } - while (more); -} - -/* Output a signed "little-endian base 128" number. */ -static void -out_sleb128 (value) - offsetT value; -{ - unsigned char byte, more = 0x80; - - do - { - byte = value & 0x7f; - value >>= 7; - if (((value == 0) && ((byte & 0x40) == 0)) - || ((value == -1) && ((byte & 0x40) != 0))) - more = 0; - out_byte (more | byte); - } - while (more); -} - -/* Encode a pair of line and address skips as efficiently as possible. - Note that the line skip is signed, whereas the address skip is - unsigned. */ -static void -gen_addr_line (line_delta, addr_delta) - int line_delta; - addressT addr_delta; -{ - unsigned int tmp, opcode; - - tmp = line_delta - DWARF2_LINE_BASE; - - if (tmp >= DWARF2_LINE_RANGE) - { - out_opcode (DW_LNS_advance_line); - out_sleb128 (line_delta); - tmp = 0 - DWARF2_LINE_BASE; - line_delta = 0; - } - - tmp += DWARF2_LINE_OPCODE_BASE; - - /* try using a special opcode: */ - opcode = tmp + addr_delta*DWARF2_LINE_RANGE; - if (opcode <= 255) - { - out_opcode (opcode); - return; - } - - /* try using DW_LNS_const_add_pc followed by special op: */ - opcode = tmp + (addr_delta - MAX_SPECIAL_ADDR_DELTA)*DWARF2_LINE_RANGE; - if (opcode <= 255) - { - out_opcode (DW_LNS_const_add_pc); - out_opcode (opcode); - return; - } - - out_opcode (DW_LNS_advance_pc); - out_uleb128 (addr_delta); - - if (line_delta) - out_opcode (tmp); /* output line-delta */ - else - out_opcode (DW_LNS_copy); /* append new row with current info */ -} - -static void -reset_state_machine () -{ - static const struct dwarf2_sm initial_state = { INITIAL_STATE }; - - ls.sm = initial_state; -} - -/* Set an absolute address (may results in a relocation entry): */ -static void -out_set_addr (addr) - addressT addr; -{ - subsegT saved_subseg; - segT saved_seg; - expressionS expr; - symbolS *sym; - int bytes_per_address; - - saved_seg = now_seg; - saved_subseg = now_subseg; - - subseg_set (ls.text_seg, ls.text_subseg); - sym = symbol_new (".L0\001", now_seg, addr, frag_now); - - subseg_set (saved_seg, saved_subseg); - -#ifdef BFD_ASSEMBLER - bytes_per_address = bfd_arch_bits_per_address (stdoutput) / 8; -#else - /* FIXME. */ - bytes_per_address = 4; -#endif - - out_opcode (DW_LNS_extended_op); - out_uleb128 (bytes_per_address + 1); - - out_opcode (DW_LNE_set_address); - expr.X_op = O_symbol; - expr.X_add_symbol = sym; - expr.X_add_number = 0; - emit_expr (&expr, bytes_per_address); -} - -/* Emit DW_LNS_end_sequence and reset state machine. Does not - preserve the current segment/sub-segment! */ -static void -out_end_sequence () -{ - addressT addr, delta; - fragS *text_frag; - - if (ls.text_seg) - { - subseg_set (ls.text_seg, ls.text_subseg); -#ifdef md_current_text_addr - addr = md_current_text_addr (); -#else - addr = frag_now_fix (); -#endif - text_frag = frag_now; - subseg_set (ls.line_seg, DL_BODY); - if (text_frag != ls.frag) - { - out_set_addr (addr); - ls.sm.addr = addr; - ls.frag = text_frag; - } - else - { - delta = (addr - ls.sm.addr) / DWARF2_LINE_MIN_INSN_LENGTH; - if (delta > 0) - { - /* Advance address without updating the line-debug - matrix---the end_sequence entry is used only to tell - the debugger the end of the sequence.*/ - out_opcode (DW_LNS_advance_pc); - out_uleb128 (delta); - } - } - } - else - subseg_set (ls.line_seg, DL_BODY); - - out_opcode (DW_LNS_extended_op); - out_uleb128 (1); - out_byte (DW_LNE_end_sequence); - - reset_state_machine (); -} - -/* Look up a filenumber either by filename or by filenumber. If both - a filenumber and a filename are specified, lookup by filename takes - precedence. If the filename cannot be found, it is added to the - filetable and the filenumber for the new entry is returned. */ -static int -get_filenum (filenum, file) - int filenum; - char *file; -{ - int i, last = filenum - 1; - char char0 = file[0]; - - /* If filenum is out of range of the filename table, then try using the - table entry returned from the previous call. */ - if (last >= ls.num_filenames || last < 0) - last = ls.last_filename; - - /* Do a quick check against the specified or previously used filenum. */ - if (ls.num_filenames > 0 && ls.file[last].name[0] == char0 - && strcmp (ls.file[last].name + 1, file + 1) == 0) - return last + 1; - - /* no match, fall back to simple linear scan: */ - for (i = 0; i < ls.num_filenames; ++i) - { - if (ls.file[i].name[0] == char0 - && strcmp (ls.file[i].name + 1, file + 1) == 0) - { - ls.last_filename = i; - return i + 1; - } - } - - /* no match: enter new filename */ - if (ls.num_filenames >= ls.filename_len) - { - ls.filename_len += 13; - ls.file = xrealloc (ls.file, ls.filename_len * sizeof (ls.file[0])); - } - ls.file[ls.num_filenames].dir = 0; - ls.file[ls.num_filenames].name = file; - ls.last_filename = ls.num_filenames; - return ++ls.num_filenames; -} - -/* Emit an entry in the line number table if the address or line has changed. - ADDR is relative to the current frag in the text section. */ - -void -dwarf2_gen_line_info (addr, l) - addressT addr; - struct dwarf2_line_info *l; -{ - unsigned int filenum = l->filenum; - unsigned int any_output = 0; - subsegT saved_subseg; - segT saved_seg; - fragS *saved_frag; - - if (flag_debug) - fprintf (stderr, "line: addr %lx file `%s' line %u col %u flags %x\n", - (unsigned long) addr, l->filename, l->line, l->column, l->flags); - - if (filenum > 0 && !l->filename) - { - if (filenum >= (unsigned int) ls.num_filenames) - { - as_warn ("Encountered bad file number in line number debug info!"); - return; - } - } - else if (l->filename) - filenum = get_filenum (filenum, l->filename); - else - return; /* no filename, no filnum => no play */ - - /* Must save these before the subseg_new call, as that call will change - them. */ - saved_seg = now_seg; - saved_subseg = now_subseg; - saved_frag = frag_now; - - if (!ls.line_seg) - { -#ifdef BFD_ASSEMBLER - symbolS *secsym; -#endif - - ls.line_seg = subseg_new (".debug_line", 0); - -#ifdef BFD_ASSEMBLER - bfd_set_section_flags (stdoutput, ls.line_seg, SEC_READONLY); - - /* We're going to need this symbol. */ - secsym = symbol_find (".debug_line"); - if (secsym != NULL) - symbol_set_bfdsym (secsym, ls.line_seg->symbol); - else - symbol_table_insert (section_symbol (ls.line_seg)); -#endif - } - - subseg_set (ls.line_seg, DL_BODY); - - if (ls.text_seg != saved_seg || ls.text_subseg != saved_subseg) - { - if (!ls.sm.empty_sequence) - { - out_end_sequence (); /* terminate previous sequence */ - ls.sm.empty_sequence = 1; - } - any_output = 1; - ls.text_seg = saved_seg; - ls.text_subseg = saved_subseg; - out_set_addr (addr); - ls.sm.addr = addr; - ls.frag = saved_frag; - } - - if (ls.sm.filenum != filenum) - { - any_output = 1; - out_opcode (DW_LNS_set_file); - out_uleb128 (filenum); - ls.sm.filenum = filenum; - } - - if (ls.sm.column != l->column) - { - any_output = 1; - out_opcode (DW_LNS_set_column); - out_uleb128 (l->column); - ls.sm.column = l->column; - } - - if (((l->flags & DWARF2_FLAG_BEGIN_STMT) != 0) != ls.sm.is_stmt) - { - any_output = 1; - out_opcode (DW_LNS_negate_stmt); - } - - if (l->flags & DWARF2_FLAG_BEGIN_BLOCK) - { - any_output = 1; - out_opcode (DW_LNS_set_basic_block); - } - - if (ls.sm.line != l->line) - { - any_output = 1; - if (saved_frag != ls.frag) - { - /* If a new frag got allocated (for whatever reason), then - deal with it by generating a reference symbol. Note: no - end_sequence needs to be generated because the address did - not really decrease (only the reference point changed). */ - out_set_addr (addr); - ls.sm.addr = addr; - ls.frag = saved_frag; - } - gen_addr_line (l->line - ls.sm.line, - (addr - ls.sm.addr) / DWARF2_LINE_MIN_INSN_LENGTH); - ls.sm.basic_block = 0; - ls.sm.line = l->line; - ls.sm.addr = addr; - } - - subseg_set (saved_seg, saved_subseg); - - ls.num_line_entries += any_output; - if (any_output) - ls.sm.empty_sequence = 0; -} - -static void -gen_dir_list () -{ - char *str, *slash, *dir_list, *dp, *cp; - int i, j, num_dirs; - - dir_list = frag_more (0); - num_dirs = 0; - - for (i = 0; i < ls.num_filenames; ++i) - { - str = ls.file[i].name; - slash = strrchr (str, '/'); - if (slash) - { - *slash = '\0'; - for (j = 0, dp = dir_list; j < num_dirs; ++j) - { - if (strcmp (str, dp) == 0) - { - ls.file[i].dir = j + 1; - break; - } - dp += strlen (dp); - } - if (j >= num_dirs) - { - /* didn't find this directory: append it to the list */ - size_t size = strlen (str) + 1; - cp = frag_more (size); - memcpy (cp, str, size); - ls.file[i].dir = ++num_dirs; - } - *slash = '/'; - ls.file[i].name = slash + 1; - } - } - out_byte ('\0'); /* terminate directory list */ -} - -static void -gen_file_list () -{ - size_t size; - char *cp; - int i; - - for (i = 0; i < ls.num_filenames; ++i) - { - size = strlen (ls.file[i].name) + 1; - cp = frag_more (size); - memcpy (cp, ls.file[i].name, size); - - out_uleb128 (ls.file[i].dir); /* directory number */ - out_uleb128 (0); /* last modification timestamp */ - out_uleb128 (0); /* filesize */ - } - out_byte (0); /* terminate filename list */ -} - -static void -print_stats (total_size) - unsigned long total_size; -{ - static const char *opc_name[] = - { - "extended", "copy", "advance_pc", "advance_line", "set_file", - "set_column", "negate_stmt", "set_basic_block", "const_add_pc", - "fixed_advance_pc" - }; - size_t i; - int j; - - fprintf (stderr, "Average size: %g bytes/line\n", - total_size / (double) ls.num_line_entries); - - fprintf (stderr, "\nStandard opcode histogram:\n"); - - for (i = 0; i < sizeof (opc_name)/sizeof (opc_name[0]); ++i) - { - fprintf (stderr, "%s", opc_name[i]); - for (j = strlen (opc_name[i]); j < 16; ++j) - fprintf (stderr, " "); - fprintf (stderr, ": %u\n", ls.opcode_hist[i]); - } - - fprintf (stderr, "\nSpecial opcodes:\naddr\t\t\t\tline skip\n"); - - fprintf (stderr, "skip: "); - for (j = DWARF2_LINE_BASE; j < DWARF2_LINE_BASE + DWARF2_LINE_RANGE; ++j) - fprintf (stderr, "%3d", j); - fprintf (stderr, "\n-----"); - - for (; i < 256; ++i) - { - j = SPECIAL_LINE (i); - if (j == DWARF2_LINE_BASE) - fprintf (stderr, "\n%4u: ", - DWARF2_LINE_MIN_INSN_LENGTH*SPECIAL_ADDR (i)); - fprintf (stderr, " %2u", ls.opcode_hist[i]); - } - fprintf (stderr, "\n"); -} - -void -dwarf2_finish () -{ - addressT body_size, total_size, prolog_size; - subsegT saved_subseg; - segT saved_seg; - char *cp; - - if (!ls.line_seg) - /* no .debug_line segment, no work to do... */ - return; - - saved_seg = now_seg; - saved_subseg = now_subseg; - - if (!ls.sm.empty_sequence) - out_end_sequence (); - total_size = body_size = frag_now_fix (); - - /* now generate the directory and file lists: */ - subseg_set (ls.line_seg, DL_FILES); - gen_dir_list (); - gen_file_list (); - total_size += frag_now_fix (); - - /* and now the header ("statement program prolog", in DWARF2 lingo...) */ - subseg_set (ls.line_seg, DL_PROLOG); - - cp = frag_more (15 + DWARF2_LINE_OPCODE_BASE - 1); - - total_size += frag_now_fix (); - prolog_size = total_size - body_size - 10; - -# define STUFF(val,size) md_number_to_chars (cp, val, size); cp += size; - STUFF (total_size - 4, 4); /* length */ - STUFF (2, 2); /* version */ - STUFF (prolog_size, 4); /* prologue_length */ - STUFF (DWARF2_LINE_MIN_INSN_LENGTH, 1); - STUFF (DWARF2_LINE_DEFAULT_IS_STMT, 1); - STUFF (DWARF2_LINE_BASE, 1); - STUFF (DWARF2_LINE_RANGE, 1); - STUFF (DWARF2_LINE_OPCODE_BASE, 1); - - /* standard_opcode_lengths: */ - STUFF (0, 1); /* DW_LNS_copy */ - STUFF (1, 1); /* DW_LNS_advance_pc */ - STUFF (1, 1); /* DW_LNS_advance_line */ - STUFF (1, 1); /* DW_LNS_set_file */ - STUFF (1, 1); /* DW_LNS_set_column */ - STUFF (0, 1); /* DW_LNS_negate_stmt */ - STUFF (0, 1); /* DW_LNS_set_basic_block */ - STUFF (0, 1); /* DW_LNS_const_add_pc */ - STUFF (1, 1); /* DW_LNS_fixed_advance_pc */ - - subseg_set (saved_seg, saved_subseg); - - if (flag_debug) - print_stats (total_size); -} - -void -dwarf2_directive_file (dummy) - int dummy ATTRIBUTE_UNUSED; -{ - int len; - - /* Continue to accept a bare string and pass it off. */ - SKIP_WHITESPACE (); - if (*input_line_pointer == '"') - { - s_app_file (0); - return; - } - - ls.any_dwarf2_directives = 1; - - if (debug_type == DEBUG_NONE) - /* Automatically turn on DWARF2 debug info unless something else - has been selected. */ - debug_type = DEBUG_DWARF2; - - ls.current.filenum = get_absolute_expression (); - ls.current.filename = demand_copy_C_string (&len); - - demand_empty_rest_of_line (); -} - -void -dwarf2_directive_loc (dummy) - int dummy ATTRIBUTE_UNUSED; -{ - ls.any_dwarf2_directives = 1; - - ls.current.filenum = get_absolute_expression (); - SKIP_WHITESPACE (); - ls.current.line = get_absolute_expression (); - SKIP_WHITESPACE (); - ls.current.column = get_absolute_expression (); - demand_empty_rest_of_line (); - - ls.current.flags = DWARF2_FLAG_BEGIN_STMT; - -#ifndef NO_LISTING - if (listing) - listing_source_line (ls.current.line); -#endif -} - -void -dwarf2_where (line) - struct dwarf2_line_info *line; -{ - if (ls.any_dwarf2_directives) - *line = ls.current; - else - { - as_where (&line->filename, &line->line); - line->filenum = 0; - line->column = 0; - line->flags = DWARF2_FLAG_BEGIN_STMT; - } -} |