diff options
Diffstat (limited to 'contrib/binutils/gas/dwarf2dbg.c')
-rw-r--r-- | contrib/binutils/gas/dwarf2dbg.c | 206 |
1 files changed, 176 insertions, 30 deletions
diff --git a/contrib/binutils/gas/dwarf2dbg.c b/contrib/binutils/gas/dwarf2dbg.c index 16666fa4f28d..671a9b030d4b 100644 --- a/contrib/binutils/gas/dwarf2dbg.c +++ b/contrib/binutils/gas/dwarf2dbg.c @@ -28,7 +28,6 @@ [epilogue_begin] [is_stmt VALUE] [isa VALUE] */ -#include "ansidecl.h" #include "as.h" #include "safe-ctype.h" @@ -46,6 +45,29 @@ #include "dwarf2dbg.h" #include <filenames.h> +#ifdef HAVE_DOS_BASED_FILE_SYSTEM +/* We need to decide which character to use as a directory separator. + Just because HAVE_DOS_BASED_FILE_SYSTEM is defined, it does not + necessarily mean that the backslash character is the one to use. + Some environments, eg Cygwin, can support both naming conventions. + So we use the heuristic that we only need to use the backslash if + the path is an absolute path starting with a DOS style drive + selector. eg C: or D: */ +# define INSERT_DIR_SEPARATOR(string, offset) \ + do \ + { \ + if (offset > 1 \ + && string[0] != 0 \ + && string[1] == ':') \ + string [offset] = '\\'; \ + else \ + string [offset] = '/'; \ + } \ + while (0) +#else +# define INSERT_DIR_SEPARATOR(string, offset) string[offset] = '/' +#endif + #ifndef DWARF2_FORMAT # define DWARF2_FORMAT() dwarf2_format_32bit #endif @@ -66,6 +88,13 @@ #define DL_FILES 1 #define DL_BODY 2 +/* If linker relaxation might change offsets in the code, the DWARF special + opcodes and variable-length operands cannot be used. If this macro is + nonzero, use the DW_LNS_fixed_advance_pc opcode instead. */ +#ifndef DWARF2_USE_FIXED_ADVANCE_PC +# define DWARF2_USE_FIXED_ADVANCE_PC 0 +#endif + /* 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 @@ -169,22 +198,22 @@ static void out_two (int); static void out_four (int); static void out_abbrev (int, int); static void out_uleb128 (addressT); -static offsetT get_frag_fix (fragS *); +static void out_sleb128 (addressT); +static offsetT get_frag_fix (fragS *, segT); static void out_set_addr (symbolS *); static int size_inc_line_addr (int, addressT); static void emit_inc_line_addr (int, addressT, char *, int); static void out_inc_line_addr (int, addressT); +static void out_fixed_inc_line_addr (int, symbolS *, symbolS *); static void relax_inc_line_addr (int, symbolS *, symbolS *); static void process_entries (segT, struct line_entry *); static void out_file_list (void); static void out_debug_line (segT); static void out_debug_aranges (segT, segT); static void out_debug_abbrev (segT); -static void out_debug_info (segT, segT, segT); #ifndef TC_DWARF2_EMIT_OFFSET -# define TC_DWARF2_EMIT_OFFSET generic_dwarf2_emit_offset -static void generic_dwarf2_emit_offset (symbolS *, unsigned int); +#define TC_DWARF2_EMIT_OFFSET generic_dwarf2_emit_offset /* Create an offset to .dwarf2_*. */ @@ -569,7 +598,7 @@ dwarf2_directive_loc (int dummy ATTRIBUTE_UNUSED) char *cp = (char *) alloca (dir_len + 1 + file_len + 1); memcpy (cp, dirs[files[filenum].dir], dir_len); - cp[dir_len] = '/'; + INSERT_DIR_SEPARATOR (cp, dir_len); memcpy (cp + dir_len + 1, files[filenum].filename, file_len); cp[dir_len + file_len + 1] = '\0'; listing_source_file (cp); @@ -670,27 +699,18 @@ dwarf2_directive_loc_mark_labels (int dummy ATTRIBUTE_UNUSED) static struct frag * first_frag_for_seg (segT seg) { - frchainS *f, *first = NULL; - - for (f = frchain_root; f; f = f->frch_next) - if (f->frch_seg == seg - && (! first || first->frch_subseg > f->frch_subseg)) - first = f; - - return first ? first->frch_root : NULL; + return seg_info (seg)->frchainP->frch_root; } static struct frag * last_frag_for_seg (segT seg) { - frchainS *f, *last = NULL; + frchainS *f = seg_info (seg)->frchainP; - for (f = frchain_root; f; f = f->frch_next) - if (f->frch_seg == seg - && (! last || last->frch_subseg < f->frch_subseg)) - last= f; + while (f->frch_next != NULL) + f = f->frch_next; - return last ? last->frch_last : NULL; + return f->frch_last; } /* Emit a single byte into the current segment. */ @@ -733,6 +753,14 @@ out_uleb128 (addressT value) output_leb128 (frag_more (sizeof_leb128 (value, 0)), value, 0); } +/* Emit a signed "little-endian base 128" number. */ + +static void +out_sleb128 (addressT value) +{ + output_leb128 (frag_more (sizeof_leb128 (value, 1)), value, 1); +} + /* Emit a tuple for .debug_abbrev. */ static inline void @@ -745,7 +773,7 @@ out_abbrev (int name, int form) /* Get the size of a fragment. */ static offsetT -get_frag_fix (fragS *frag) +get_frag_fix (fragS *frag, segT seg) { frchainS *fr; @@ -755,7 +783,7 @@ get_frag_fix (fragS *frag) /* If a fragment is the last in the chain, special measures must be taken to find its size before relaxation, since it may be pending on some subsegment chain. */ - for (fr = frchain_root; fr; fr = fr->frch_next) + for (fr = seg_info (seg)->frchainP; fr; fr = fr->frch_next) if (fr->frch_last == frag) return (char *) obstack_next_free (&fr->frch_obstack) - frag->fr_literal; @@ -966,6 +994,45 @@ out_inc_line_addr (int line_delta, addressT addr_delta) emit_inc_line_addr (line_delta, addr_delta, frag_more (len), len); } +/* Write out an alternative form of line and address skips using + DW_LNS_fixed_advance_pc opcodes. This uses more space than the default + line and address information, but it helps support linker relaxation that + changes the code offsets. */ + +static void +out_fixed_inc_line_addr (int line_delta, symbolS *to_sym, symbolS *from_sym) +{ + expressionS expr; + + /* INT_MAX is a signal that this is actually a DW_LNE_end_sequence. */ + if (line_delta == INT_MAX) + { + out_opcode (DW_LNS_fixed_advance_pc); + expr.X_op = O_subtract; + expr.X_add_symbol = to_sym; + expr.X_op_symbol = from_sym; + expr.X_add_number = 0; + emit_expr (&expr, 2); + + out_opcode (DW_LNS_extended_op); + out_byte (1); + out_opcode (DW_LNE_end_sequence); + return; + } + + out_opcode (DW_LNS_advance_line); + out_sleb128 (line_delta); + + out_opcode (DW_LNS_fixed_advance_pc); + expr.X_op = O_subtract; + expr.X_add_symbol = to_sym; + expr.X_op_symbol = from_sym; + expr.X_add_number = 0; + emit_expr (&expr, 2); + + out_opcode (DW_LNS_copy); +} + /* Generate a variant frag that we can use to relax address/line increments between fragments of the target segment. */ @@ -1116,6 +1183,8 @@ process_entries (segT seg, struct line_entry *e) out_set_addr (lab); out_inc_line_addr (line_delta, 0); } + else if (DWARF2_USE_FIXED_ADVANCE_PC) + out_fixed_inc_line_addr (line_delta, lab, last_lab); else if (frag == last_frag) out_inc_line_addr (line_delta, frag_ofs - last_frag_ofs); else @@ -1134,8 +1203,13 @@ process_entries (segT seg, struct line_entry *e) /* Emit a DW_LNE_end_sequence for the end of the section. */ frag = last_frag_for_seg (seg); - frag_ofs = get_frag_fix (frag); - if (frag == last_frag) + frag_ofs = get_frag_fix (frag, seg); + if (DWARF2_USE_FIXED_ADVANCE_PC) + { + lab = symbol_temp_new (seg, frag_ofs, frag); + out_fixed_inc_line_addr (INT_MAX, lab, last_lab); + } + else if (frag == last_frag) out_inc_line_addr (INT_MAX, frag_ofs - last_frag_ofs); else { @@ -1277,6 +1351,54 @@ out_debug_line (segT line_seg) symbol_set_value_now (line_end); } +static void +out_debug_ranges (segT ranges_seg) +{ + unsigned int addr_size = sizeof_address; + struct line_seg *s; + expressionS expr; + unsigned int i; + + subseg_set (ranges_seg, 0); + + /* Base Address Entry. */ + for (i = 0; i < addr_size; i++) + out_byte (0xff); + for (i = 0; i < addr_size; i++) + out_byte (0); + + /* Range List Entry. */ + for (s = all_segs; s; s = s->next) + { + fragS *frag; + symbolS *beg, *end; + + frag = first_frag_for_seg (s->seg); + beg = symbol_temp_new (s->seg, 0, frag); + s->text_start = beg; + + frag = last_frag_for_seg (s->seg); + end = symbol_temp_new (s->seg, get_frag_fix (frag, s->seg), frag); + s->text_end = end; + + expr.X_op = O_symbol; + expr.X_add_symbol = beg; + expr.X_add_number = 0; + emit_expr (&expr, addr_size); + + expr.X_op = O_symbol; + expr.X_add_symbol = end; + expr.X_add_number = 0; + emit_expr (&expr, addr_size); + } + + /* End of Range Entry. */ + for (i = 0; i < addr_size; i++) + out_byte (0); + for (i = 0; i < addr_size; i++) + out_byte (0); +} + /* Emit data for .debug_aranges. */ static void @@ -1332,7 +1454,7 @@ out_debug_aranges (segT aranges_seg, segT info_seg) s->text_start = beg; frag = last_frag_for_seg (s->seg); - end = symbol_temp_new (s->seg, get_frag_fix (frag), frag); + end = symbol_temp_new (s->seg, get_frag_fix (frag, s->seg), frag); s->text_end = end; expr.X_op = O_symbol; @@ -1369,6 +1491,13 @@ out_debug_abbrev (segT abbrev_seg) out_abbrev (DW_AT_low_pc, DW_FORM_addr); out_abbrev (DW_AT_high_pc, DW_FORM_addr); } + else + { + if (DWARF2_FORMAT () == dwarf2_format_32bit) + out_abbrev (DW_AT_ranges, DW_FORM_data4); + else + out_abbrev (DW_AT_ranges, DW_FORM_data8); + } out_abbrev (DW_AT_name, DW_FORM_string); out_abbrev (DW_AT_comp_dir, DW_FORM_string); out_abbrev (DW_AT_producer, DW_FORM_string); @@ -1382,7 +1511,7 @@ out_debug_abbrev (segT abbrev_seg) /* Emit a description of this compilation unit for .debug_info. */ static void -out_debug_info (segT info_seg, segT abbrev_seg, segT line_seg) +out_debug_info (segT info_seg, segT abbrev_seg, segT line_seg, segT ranges_seg) { char producer[128]; char *comp_dir; @@ -1445,8 +1574,7 @@ out_debug_info (segT info_seg, segT abbrev_seg, segT line_seg) /* ??? sizeof_offset */ TC_DWARF2_EMIT_OFFSET (section_symbol (line_seg), 4); - /* These two attributes may only be emitted if all of the code is - contiguous. Multiple sections are not that. */ + /* These two attributes are emitted if all of the code is contiguous. */ if (all_segs->next == NULL) { /* DW_AT_low_pc */ @@ -1461,6 +1589,12 @@ out_debug_info (segT info_seg, segT abbrev_seg, segT line_seg) expr.X_add_number = 0; emit_expr (&expr, sizeof_address); } + else + { + /* This attribute is emitted if the code is disjoint. */ + /* DW_AT_ranges. */ + TC_DWARF2_EMIT_OFFSET (section_symbol (ranges_seg), sizeof_offset); + } /* DW_AT_name. We don't have the actual file name that was present on the command line, so assume files[1] is the main input file. @@ -1473,7 +1607,7 @@ out_debug_info (segT info_seg, segT abbrev_seg, segT line_seg) len = strlen (dirs[files[1].dir]); p = frag_more (len + 1); memcpy (p, dirs[files[1].dir], len); - p[len] = '/'; + INSERT_DIR_SEPARATOR (p, len); } len = strlen (files[1].filename) + 1; p = frag_more (len); @@ -1551,6 +1685,7 @@ dwarf2_finish (void) { segT abbrev_seg; segT aranges_seg; + segT ranges_seg; assert (all_segs); @@ -1567,8 +1702,19 @@ dwarf2_finish (void) record_alignment (aranges_seg, ffs (2 * sizeof_address) - 1); + if (all_segs->next == NULL) + ranges_seg = NULL; + else + { + ranges_seg = subseg_new (".debug_ranges", 0); + bfd_set_section_flags (stdoutput, ranges_seg, + SEC_READONLY | SEC_DEBUGGING); + record_alignment (ranges_seg, ffs (2 * sizeof_address) - 1); + out_debug_ranges (ranges_seg); + } + out_debug_aranges (aranges_seg, info_seg); out_debug_abbrev (abbrev_seg); - out_debug_info (info_seg, abbrev_seg, line_seg); + out_debug_info (info_seg, abbrev_seg, line_seg, ranges_seg); } } |