diff options
Diffstat (limited to 'gdb/dwarf2read.c')
| -rw-r--r-- | gdb/dwarf2read.c | 144 |
1 files changed, 144 insertions, 0 deletions
diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c index 1154b11..2a5acf0 100644 --- a/gdb/dwarf2read.c +++ b/gdb/dwarf2read.c @@ -17765,6 +17765,150 @@ dwarf2_fetch_die_loc_cu_off (cu_offset offset_in_cu, return dwarf2_fetch_die_loc_sect_off (offset, per_cu, get_frame_pc, baton); } +/* Write a constant of a given type as target-ordered bytes into + OBSTACK. */ + +static const gdb_byte * +write_constant_as_bytes (struct obstack *obstack, + enum bfd_endian byte_order, + struct type *type, + ULONGEST value, + LONGEST *len) +{ + gdb_byte *result; + + *len = TYPE_LENGTH (type); + result = obstack_alloc (obstack, *len); + store_unsigned_integer (result, *len, byte_order, value); + + return result; +} + +/* If the DIE at OFFSET in PER_CU has a DW_AT_const_value, return a + pointer to the constant bytes and set LEN to the length of the + data. If memory is needed, allocate it on OBSTACK. If the DIE + does not have a DW_AT_const_value, return NULL. */ + +const gdb_byte * +dwarf2_fetch_constant_bytes (sect_offset offset, + struct dwarf2_per_cu_data *per_cu, + struct obstack *obstack, + LONGEST *len) +{ + struct dwarf2_cu *cu; + struct die_info *die; + struct attribute *attr; + const gdb_byte *result = NULL; + struct type *type; + LONGEST value; + enum bfd_endian byte_order; + + dw2_setup (per_cu->objfile); + + if (per_cu->cu == NULL) + load_cu (per_cu); + cu = per_cu->cu; + + die = follow_die_offset (offset, per_cu->is_dwz, &cu); + if (!die) + error (_("Dwarf Error: Cannot find DIE at 0x%x referenced in module %s"), + offset.sect_off, per_cu->objfile->name); + + + attr = dwarf2_attr (die, DW_AT_const_value, cu); + if (attr == NULL) + return NULL; + + byte_order = (bfd_big_endian (per_cu->objfile->obfd) + ? BFD_ENDIAN_BIG : BFD_ENDIAN_LITTLE); + + switch (attr->form) + { + case DW_FORM_addr: + case DW_FORM_GNU_addr_index: + { + gdb_byte *tem; + + *len = cu->header.addr_size; + tem = obstack_alloc (obstack, *len); + store_unsigned_integer (tem, *len, byte_order, DW_ADDR (attr)); + result = tem; + } + break; + case DW_FORM_string: + case DW_FORM_strp: + case DW_FORM_GNU_str_index: + case DW_FORM_GNU_strp_alt: + /* DW_STRING is already allocated on the objfile obstack, point + directly to it. */ + result = (const gdb_byte *) DW_STRING (attr); + *len = strlen (DW_STRING (attr)); + break; + case DW_FORM_block1: + case DW_FORM_block2: + case DW_FORM_block4: + case DW_FORM_block: + case DW_FORM_exprloc: + result = DW_BLOCK (attr)->data; + *len = DW_BLOCK (attr)->size; + break; + + /* The DW_AT_const_value attributes are supposed to carry the + symbol's value "represented as it would be on the target + architecture." By the time we get here, it's already been + converted to host endianness, so we just need to sign- or + zero-extend it as appropriate. */ + case DW_FORM_data1: + type = die_type (die, cu); + result = dwarf2_const_value_data (attr, obstack, cu, &value, 8); + if (result == NULL) + result = write_constant_as_bytes (obstack, byte_order, + type, value, len); + break; + case DW_FORM_data2: + type = die_type (die, cu); + result = dwarf2_const_value_data (attr, obstack, cu, &value, 16); + if (result == NULL) + result = write_constant_as_bytes (obstack, byte_order, + type, value, len); + break; + case DW_FORM_data4: + type = die_type (die, cu); + result = dwarf2_const_value_data (attr, obstack, cu, &value, 32); + if (result == NULL) + result = write_constant_as_bytes (obstack, byte_order, + type, value, len); + break; + case DW_FORM_data8: + type = die_type (die, cu); + result = dwarf2_const_value_data (attr, obstack, cu, &value, 64); + if (result == NULL) + result = write_constant_as_bytes (obstack, byte_order, + type, value, len); + break; + + case DW_FORM_sdata: + type = die_type (die, cu); + result = write_constant_as_bytes (obstack, byte_order, + type, DW_SND (attr), len); + break; + + case DW_FORM_udata: + type = die_type (die, cu); + result = write_constant_as_bytes (obstack, byte_order, + type, DW_UNSND (attr), len); + break; + + default: + complaint (&symfile_complaints, + _("unsupported const value attribute form: '%s'"), + dwarf_form_name (attr->form)); + break; + } + + return result; +} + /* Return the type of the DIE at DIE_OFFSET in the CU named by PER_CU. */ |