static U8_T read_frame_data_pointer(U1_T encoding, ELF_Section ** sec, U8_T func_addr) {
U8_T v = 0;
U8_T pos;
unsigned idx;
ELF_File * file;
if (encoding == EH_PE_omit) return 0;
pos = dio_GetPos();
/* Decode the base or adjust the offset */
switch ((encoding >> 4) & 0x7) {
case 0:
case EH_PB_funcrel:
v = func_addr;
break;
case EH_PB_pcrel:
if (sec != NULL) {
v = pos + rules.section->addr;
}
break;
case EH_PB_datarel:
if (sec != NULL) {
v = rules.section->addr;
}
break;
case EH_PB_textrel:
if (sec != NULL && rules.text_section != NULL) {
v = rules.text_section->addr;
}
break;
case EH_PB_aligned:
if ((pos % rules.address_size) != 0) dio_SetPos(pos + (rules.address_size - (pos % rules.address_size)));
break;
default:
str_exception(ERR_INV_DWARF, "Unknown encoding of .eh_frame section pointers");
break;
}
/* Decode the value */
switch (encoding & 0xf) {
case EH_PE_absptr:
v += dio_ReadAddress(sec);
break;
case EH_PE_uleb128:
v += dio_ReadU8LEB128();
break;
case EH_PE_udata2:
v += dio_ReadAddressX(sec, 2);
break;
case EH_PE_udata4:
v += dio_ReadAddressX(sec, 4);
break;
case EH_PE_udata8:
v += dio_ReadAddressX(sec, 8);
break;
case EH_PE_sleb128:
v += dio_ReadS8LEB128();
break;
case EH_PE_sdata2:
v += (I2_T)dio_ReadAddressX(sec, 2);
break;
case EH_PE_sdata4:
v += (I4_T)dio_ReadAddressX(sec, 4);
break;
case EH_PE_sdata8:
v += (I8_T)dio_ReadAddressX(sec, 8);
break;
default:
str_exception(ERR_INV_DWARF, "Unknown encoding of .eh_frame section pointers");
break;
}
if (encoding & EH_PE_indirect) {
size_t size = rules.address_size;
U8_T res = 0;
file = rules.section->file;
for (idx = 1; idx < file->section_cnt; idx++) {
ELF_Section * sec = file->sections + idx;
if ((sec->flags & SHF_ALLOC) == 0) continue;
if (sec->addr <= v && sec->addr + sec->size >= v + size) {
U1_T * p;
size_t i;
if (sec->data == NULL && elf_load(sec) < 0) exception(errno);
p = (U1_T *)sec->data + (uintptr_t)(v - sec->addr);
for (i = 0; i < size; i++) {
res = (res << 8) | p[file->big_endian ? i : size - i - 1];
}
break;
}
}
v = res;
}
return v;
}
static void add_dwarf_expression_commands(U8_T cmds_offs, U4_T cmds_size) {
dio_EnterSection(NULL, rules.section, cmds_offs);
while (dio_GetPos() < cmds_offs + cmds_size) {
U1_T op = dio_ReadU1();
switch (op) {
case OP_addr:
{
ELF_Section * section = NULL;
U8_T lt_addr = dio_ReadAddress(§ion);
ContextAddress rt_addr = elf_map_to_run_time_address(
rules.ctx, rules.section->file, section, (ContextAddress)lt_addr);
if (errno) str_exception(errno, "Cannot get object run-time address");
add_command(SFT_CMD_NUMBER)->args.num = rt_addr;
}
break;
case OP_deref:
{
LocationExpressionCommand * cmd = add_command(SFT_CMD_RD_MEM);
cmd->args.mem.size = rules.address_size;
cmd->args.mem.big_endian = rules.reg_id_scope.big_endian;
}
break;
case OP_deref_size:
{
LocationExpressionCommand * cmd = add_command(SFT_CMD_RD_MEM);
cmd->args.mem.size = dio_ReadU1();
cmd->args.mem.big_endian = rules.reg_id_scope.big_endian;
}
break;
case OP_const1u:
add_command(SFT_CMD_NUMBER)->args.num = dio_ReadU1();
break;
case OP_const1s:
add_command(SFT_CMD_NUMBER)->args.num = (I1_T)dio_ReadU1();
break;
case OP_const2u:
add_command(SFT_CMD_NUMBER)->args.num = dio_ReadU2();
break;
case OP_const2s:
add_command(SFT_CMD_NUMBER)->args.num = (I2_T)dio_ReadU2();
break;
case OP_const4u:
add_command(SFT_CMD_NUMBER)->args.num = dio_ReadU4();
break;
case OP_const4s:
add_command(SFT_CMD_NUMBER)->args.num = (I4_T)dio_ReadU4();
break;
case OP_const8u:
add_command(SFT_CMD_NUMBER)->args.num = dio_ReadU8();
break;
case OP_const8s:
add_command(SFT_CMD_NUMBER)->args.num = (I8_T)dio_ReadU8();
break;
case OP_constu:
add_command(SFT_CMD_NUMBER)->args.num = dio_ReadU8LEB128();
break;
case OP_consts:
add_command(SFT_CMD_NUMBER)->args.num = dio_ReadS8LEB128();
break;
case OP_and:
add_command(SFT_CMD_AND);
break;
case OP_minus:
add_command(SFT_CMD_SUB);
break;
case OP_or:
add_command(SFT_CMD_OR);
break;
case OP_plus:
add_command(SFT_CMD_ADD);
break;
case OP_plus_uconst:
add_command(SFT_CMD_NUMBER)->args.num = dio_ReadU8LEB128();
add_command(SFT_CMD_ADD);
break;
case OP_ge:
add_command(SFT_CMD_GE);
break;
case OP_gt:
add_command(SFT_CMD_GT);
break;
case OP_le:
add_command(SFT_CMD_LE);
break;
case OP_lt:
add_command(SFT_CMD_LT);
break;
case OP_shl:
add_command(SFT_CMD_SHL);
break;
case OP_lit0:
case OP_lit1:
case OP_lit2:
case OP_lit3:
case OP_lit4:
case OP_lit5:
case OP_lit6:
case OP_lit7:
case OP_lit8:
case OP_lit9:
case OP_lit10:
case OP_lit11:
case OP_lit12:
case OP_lit13:
case OP_lit14:
case OP_lit15:
case OP_lit16:
case OP_lit17:
case OP_lit18:
case OP_lit19:
case OP_lit20:
case OP_lit21:
case OP_lit22:
case OP_lit23:
case OP_lit24:
case OP_lit25:
case OP_lit26:
case OP_lit27:
case OP_lit28:
case OP_lit29:
case OP_lit30:
case OP_lit31:
add_command(SFT_CMD_NUMBER)->args.num = op - OP_lit0;
break;
case OP_reg0:
case OP_reg1:
case OP_reg2:
case OP_reg3:
case OP_reg4:
case OP_reg5:
case OP_reg6:
case OP_reg7:
case OP_reg8:
case OP_reg9:
case OP_reg10:
case OP_reg11:
case OP_reg12:
case OP_reg13:
case OP_reg14:
case OP_reg15:
case OP_reg16:
case OP_reg17:
case OP_reg18:
case OP_reg19:
case OP_reg20:
case OP_reg21:
case OP_reg22:
case OP_reg23:
case OP_reg24:
case OP_reg25:
case OP_reg26:
case OP_reg27:
case OP_reg28:
case OP_reg29:
case OP_reg30:
case OP_reg31:
{
RegisterDefinition * def = get_reg_by_id(rules.ctx, op - OP_reg0, &rules.reg_id_scope);
if (def == NULL) str_exception(errno, "Cannot read DWARF frame info");
add_command(SFT_CMD_RD_REG)->args.reg = def;
}
break;
case OP_regx:
{
unsigned n = (unsigned)dio_ReadULEB128();
RegisterDefinition * def = get_reg_by_id(rules.ctx, n, &rules.reg_id_scope);
if (def == NULL) str_exception(errno, "Cannot read DWARF frame info");
add_command(SFT_CMD_RD_REG)->args.reg = def;
}
break;
case OP_breg0:
case OP_breg1:
case OP_breg2:
case OP_breg3:
case OP_breg4:
case OP_breg5:
case OP_breg6:
case OP_breg7:
case OP_breg8:
case OP_breg9:
case OP_breg10:
case OP_breg11:
case OP_breg12:
case OP_breg13:
case OP_breg14:
case OP_breg15:
case OP_breg16:
case OP_breg17:
case OP_breg18:
case OP_breg19:
case OP_breg20:
case OP_breg21:
case OP_breg22:
case OP_breg23:
case OP_breg24:
case OP_breg25:
case OP_breg26:
case OP_breg27:
case OP_breg28:
case OP_breg29:
case OP_breg30:
case OP_breg31:
{
I8_T offs = dio_ReadS8LEB128();
RegisterDefinition * def = get_reg_by_id(rules.ctx, op - OP_breg0, &rules.reg_id_scope);
if (def == NULL) str_exception(errno, "Cannot read DWARF frame info");
add_command(SFT_CMD_RD_REG)->args.reg = def;
if (offs != 0) {
add_command(SFT_CMD_NUMBER)->args.num = offs;
add_command(SFT_CMD_ADD);
}
}
break;
case OP_bregx:
{
unsigned n = (unsigned)dio_ReadULEB128();
I8_T offs = dio_ReadS8LEB128();
RegisterDefinition * def = get_reg_by_id(rules.ctx, n, &rules.reg_id_scope);
if (def == NULL) str_exception(errno, "Cannot read DWARF frame info");
add_command(SFT_CMD_RD_REG)->args.reg = def;
if (offs != 0) {
add_command(SFT_CMD_NUMBER)->args.num = offs;
add_command(SFT_CMD_ADD);
}
}
break;
case OP_nop:
break;
default:
trace(LOG_ALWAYS, "Unsupported DWARF expression op 0x%02x", op);
str_exception(ERR_UNSUPPORTED, "Unsupported DWARF expression op");
}
}
}
static U8_T read_frame_data_pointer(U1_T encoding, ELF_Section ** sec) {
U8_T v = 0;
if (encoding != EH_PE_omit) {
U8_T pos = dio_GetPos();
switch (encoding & 0xf) {
case EH_PE_absptr:
v = dio_ReadAddress(sec);
break;
case EH_PE_uleb128:
v = dio_ReadU8LEB128();
break;
case EH_PE_udata2:
v = dio_ReadU2();
break;
case EH_PE_udata4:
v = dio_ReadU4();
break;
case EH_PE_udata8:
v = dio_ReadU8();
break;
case EH_PE_sleb128:
v = dio_ReadS8LEB128();
break;
case EH_PE_sdata2:
v = (I2_T)dio_ReadU2();
break;
case EH_PE_sdata4:
v = (I4_T)dio_ReadU4();
break;
case EH_PE_sdata8:
v = (I8_T)dio_ReadU8();
break;
default:
str_exception(ERR_INV_DWARF, "Unknown encoding of .eh_frame section pointers");
break;
}
if (v != 0 && sec != NULL) {
switch ((encoding >> 4) & 0x7) {
case 0:
break;
case EH_PB_pcrel:
*sec = rules.section;
v += rules.section->addr + pos;
break;
case EH_PB_datarel:
*sec = rules.section;
v += rules.section->addr;
break;
case EH_PB_textrel:
case EH_PB_funcrel:
case EH_PB_aligned:
default:
str_exception(ERR_INV_DWARF, "Unknown encoding of .eh_frame section pointers");
break;
}
if (encoding & EH_PE_indirect) {
unsigned idx;
ELF_File * file = rules.section->file;
size_t size = rules.address_size;
U8_T res = 0;
for (idx = 1; idx < file->section_cnt; idx++) {
ELF_Section * sec = file->sections + idx;
if ((sec->flags & SHF_ALLOC) == 0) continue;
if (sec->addr <= v && sec->addr + sec->size >= v + size) {
U1_T * p;
size_t i;
if (sec->data == NULL && elf_load(sec) < 0) exception(errno);
p = (U1_T *)sec->data + (uintptr_t)(v - sec->addr);
for (i = 0; i < size; i++) {
res = (res << 8) | p[file->big_endian ? i : size - i - 1];
}
break;
}
}
v = res;
}
}
}
