Files
OSACA/osaca/semantics/isa_semantics.py
2019-10-29 09:15:54 +01:00

117 lines
4.3 KiB
Python
Executable File

#!/usr/bin/env python3
from osaca import utils
from osaca.parser import AttrDict, ParserAArch64v81, ParserX86ATT
from .hw_model import MachineModel
class INSTR_FLAGS:
"""
Flags used for unknown or special instructions
"""
LD = 'is_load_instruction'
TP_UNKWN = 'tp_unknown'
LT_UNKWN = 'lt_unknown'
NOT_BOUND = 'not_bound'
HIDDEN_LD = 'hidden_load'
HAS_LD = 'performs_load'
HAS_ST = 'performs_store'
class ISASemantics(object):
def __init__(self, isa, path_to_yaml=None):
self._isa = isa.lower()
path = utils.find_file('isa/' + self._isa + '.yml') if not path_to_yaml else path_to_yaml
self._isa_model = MachineModel(path_to_yaml=path)
if self._isa == 'x86':
self._parser = ParserX86ATT()
elif self._isa == 'aarch64':
self._parser = ParserAArch64v81()
# get ;parser result and assign operands to
# - source
# - destination
# - source/destination
def assign_src_dst(self, instruction_form):
# if the instruction form doesn't have operands, there's nothing to do
if instruction_form['operands'] is None:
return
# check if instruction form is in ISA yaml, otherwise apply standard operand assignment
# (one dest, others source)
isa_data = self._isa_model.get_instruction(
instruction_form['instruction'], instruction_form['operands']
)
operands = instruction_form['operands']
op_dict = {}
if isa_data is None:
# no irregular operand structure, apply default
op_dict['source'] = self._get_regular_source_operands(instruction_form)
op_dict['destination'] = self._get_regular_destination_operands(instruction_form)
op_dict['src_dst'] = []
else:
# load src/dst structure from isa_data
op_dict['source'] = []
op_dict['destination'] = []
op_dict['src_dst'] = []
for i, op in enumerate(isa_data['operands']):
if op['source'] and op['destination']:
op_dict['src_dst'].append(operands[i])
continue
if op['source']:
op_dict['source'].append(operands[i])
continue
if op['destination']:
op_dict['destination'].append(operands[i])
continue
# store operand list in dict and reassign operand key/value pair
op_dict['operand_list'] = operands
instruction_form['operands'] = AttrDict.convert_dict(op_dict)
# assign LD/ST flags
instruction_form['flags'] = (
instruction_form['flags'] if 'flags' in instruction_form else []
)
if self._has_load(instruction_form):
instruction_form['flags'] += [INSTR_FLAGS.HAS_LD]
if self._has_store(instruction_form):
instruction_form['flags'] += [INSTR_FLAGS.HAS_ST]
def _has_load(self, instruction_form):
for operand in (
instruction_form['operands']['source'] + instruction_form['operands']['src_dst']
):
if 'memory' in operand:
return True
return False
def _has_store(self, instruction_form):
for operand in (
instruction_form['operands']['destination'] + instruction_form['operands']['src_dst']
):
if 'memory' in operand:
return True
return False
def _get_regular_source_operands(self, instruction_form):
if self._isa == 'x86':
# return all but last operand
return [
op for op in instruction_form['operands'][0:len(instruction_form['operands']) - 1]
]
elif self._isa == 'aarch64':
return [
op for op in instruction_form['operands'][1:len(instruction_form['operands'])]
]
else:
raise ValueError("Unsupported ISA {}.".format(self._isa))
def _get_regular_destination_operands(self, instruction_form):
if self._isa == 'x86':
# return last operand
return instruction_form['operands'][-1:]
if self._isa == 'aarch64':
# return first operand
return instruction_form['operands'][:1]
else:
raise ValueError("Unsupported ISA {}.".format(self._isa))