def __eval_offset(self):
bitoffset = get_attr_val(self.die, 'DW_AT_data_bit_offset')
if bitoffset is not None:
# Bit offset is given directly
return bitoffset
location = get_attr_val(self.die, 'DW_AT_data_member_location')
if location is None:
# no offset attribute exists -- the member is located at the beginning of its parent
return 0
elif isinstance(location, (int, long)):
# the attribute is a number -- this is the offset in bytes
return location * 8
elif isinstance(location, list):
# the attribute is an expression
dwxpr = location
if dwxpr[0] == dwarf_expr.DW_OP_name2opcode['DW_OP_plus_uconst']:
# Right now we only support location descriptions in the form [DW_OP_plus_uconst, <ULEB128>].
# This is the only form GCC and clang produce.
return LEB.decode(BytesIO(bytearray(dwxpr[1:]))) * 8
else:
opcode = dwarf_expr.DW_OP_opcode2name.get(
dwxpr[0], '<unknown>')
raise NotImplementedError(
'Unsupported opcode in data member location %s (%02x)' %
(opcode, dwxpr[0]))
assert False, 'Unreachable code.'
def __eval_offset(self):
bitoffset = get_attr_val(self.die, 'DW_AT_data_bit_offset')
if bitoffset is not None:
# Bit offset is given directly
return bitoffset
location = get_attr_val(self.die, 'DW_AT_data_member_location')
if location is None:
# no offset attribute exists -- the member is located at the beginning of its parent
return 0
elif isinstance(location, (int, long)):
# the attribute is a number -- this is the offset in bytes
return location * 8
elif isinstance(location, list):
# the attribute is an expression
dwxpr = location
if dwxpr[0] == dwarf_expr.DW_OP_name2opcode['DW_OP_plus_uconst']:
# Right now we only support location descriptions in the form [DW_OP_plus_uconst, <ULEB128>].
# This is the only form GCC and clang produce.
return LEB.decode(BytesIO(bytearray(dwxpr[1:]))) * 8
else:
opcode = dwarf_expr.DW_OP_opcode2name.get(dwxpr[0], '<unknown>')
raise NotImplementedError('Unsupported opcode in data member location %s (%02x)' % (opcode, dwxpr[0]))
assert False, 'Unreachable code.'
def decode_offset(member_location):
'''Convert dwarf expression in DW_AT_data_member_location to offset from structure start.'''
if member_location is None:
# the attribute does not exist -- the member is located at the beginning of its parent
return 0
elif isinstance(member_location, int):
# the attribute is a number -- this is the offset
return member_location
elif isinstance(member_location, list):
# the attribute is an expression
dwxpr = member_location
if dwxpr[0] == dwarf_expr.DW_OP_name2opcode['DW_OP_plus_uconst']:
# Right now we only support location descriptions in the form [DW_OP_plus_uconst, <ULEB128>].
# This is the only form GCC and clang produce.
return LEB.decode(BytesIO(bytearray(dwxpr[1:])))
else:
opcode = dwarf_expr.DW_OP_opcode2name.get(dwxpr[0], '<unknown>')
raise NotImplementedError('Unsupported opcode in data member location %s (%02x)' % (opcode, dwxpr[0]))
def decode_offset(member_location):
'''Convert dwarf expression in DW_AT_data_member_location to offset from structure start.'''
if member_location is None:
# the attribute does not exist -- the member is located at the beginning of its parent
return 0
elif isinstance(member_location, int):
# the attribute is a number -- this is the offset
return member_location
elif isinstance(member_location, list):
# the attribute is an expression
dwxpr = member_location
if dwxpr[0] == dwarf_expr.DW_OP_name2opcode['DW_OP_plus_uconst']:
# Right now we only support location descriptions in the form [DW_OP_plus_uconst, <ULEB128>].
# This is the only form GCC and clang produce.
return LEB.decode(BytesIO(bytearray(dwxpr[1:])))
else:
opcode = dwarf_expr.DW_OP_opcode2name.get(dwxpr[0], '<unknown>')
raise NotImplementedError(
'Unsupported opcode in data member location %s (%02x)' %
(opcode, dwxpr[0]))
def regx(self):
regnum = LEB.decode(self.expression)
return 'get_reg(%i)' % regnum
def bregx(self):
'''The DW_OP_bregx operation has two operands: a register which is specified by an unsigned LEB128 number,
followed by a signed LEB128 offset.'''
regnum = LEB.decode(self.expression)
return self.bregN(regnum)
def constu(self):
'''The single operand of the DW_OP_constu operation provides an unsigned LEB128 integer constant.'''
val = LEB.decode(self.expression)
self.push('%#x' % val)
def regx(self):
regnum = LEB.decode(self.expression)
return 'get_reg(%i)' % regnum
def bregx(self):
'''The DW_OP_bregx operation has two operands: a register which is specified by an unsigned LEB128 number,
followed by a signed LEB128 offset.'''
regnum = LEB.decode(self.expression)
return self.bregN(regnum)
def constu(self):
'''The single operand of the DW_OP_constu operation provides an unsigned LEB128 integer constant.'''
val = LEB.decode(self.expression)
self.push('%#x' % val)
