class SingleOpcodeDecoder(object):
def __init__(self, text):
bit_format, effect_format = text.split('@', 2)
items = bit_format.split(None, 3)
self.bitPattern = items[0]
self.cycles = int(items[1])
self.name = items[2]
operandText = ""
if len(items) >= 4:
operandText = items[3]
if not operandText:
self.operands = []
else:
self.operands = [x.strip() for x in operandText.split(", ")]
if "v16" in operandText:
self.argSize = 2
elif "v8" in operandText:
self.argSize = 1
else:
self.argSize = 0
assert len(self.bitPattern) == 8
self.effect = OpcodeEffect(effect_format)
def matchBits(self, opcode):
params = defaultdict(int)
opcode_bits = bin(opcode)[2:].zfill(8)
for (x, y) in zip(self.bitPattern, opcode_bits):
if x in ('0', '1'):
if x != y:
return None
else:
# update according parameter
params[x] <<= 1
params[x] |= int(y)
return params
def match(self, opcode):
return self.matchBits(opcode) is not None
def length(self):
return 1 + self.argSize
def decode(self, proj, opcodes, addr):
assert len(opcodes) == self.length()
params = self.matchBits(opcodes[0])
argument = 0
if self.argSize == 1:
argument = opcodes[1]
elif self.argSize == 2:
argument = (opcodes[2] << 8) | opcodes[1]
next_addr = addr.offset(self.length())
out_operands = [
fillOperand(text, params, argument, next_addr)
for text in self.operands
]
reads, writes, values, loads = self.effect.filled(
params, make_context(params, argument, next_addr))
return instruction.make(proj, self.name, out_operands, addr, reads,
writes, values, loads), next_addr
class SingleOpcodeDecoder(object):
def __init__(self, text):
bit_format, effect_format = text.split('@', 2)
items = bit_format.split(None, 3)
self.bitPattern = items[0]
self.cycles = int(items[1])
self.name = items[2];
operandText = "";
if len(items) >= 4:
operandText = items[3]
if not operandText:
self.operands = []
else:
self.operands = [x.strip() for x in operandText.split(", ")]
if "v16" in operandText:
self.argSize = 2;
elif "v8" in operandText:
self.argSize = 1;
else:
self.argSize = 0;
assert len(self.bitPattern) == 8
self.effect = OpcodeEffect(effect_format)
def matchBits(self, opcode):
params = defaultdict(int)
opcode_bits = bin(opcode)[2:].zfill(8)
for (x, y) in zip(self.bitPattern, opcode_bits):
if x in ('0', '1'):
if x != y:
return None
else:
# update according parameter
params[x] <<= 1
params[x] |= int(y)
return params
def match(self, opcode):
return self.matchBits(opcode) is not None
def length(self):
return 1 + self.argSize
def decode(self, proj, opcodes, addr):
assert len(opcodes) == self.length()
params = self.matchBits(opcodes[0])
argument = 0
if self.argSize == 1:
argument = opcodes[1]
elif self.argSize == 2:
argument = (opcodes[2] << 8) | opcodes[1];
next_addr = addr.offset(self.length())
out_operands = [
fillOperand(text, params, argument, next_addr) for text in self.operands
]
reads, writes, values, loads = self.effect.filled(params, make_context(params, argument, next_addr))
return instruction.make(proj, self.name, out_operands, addr, reads, writes, values, loads), next_addr
class SingleOpcodeDecoder(object):
def __init__(self, text):
"""
Initialise the Single Opcode Decoder by parsing the opcode text string which contains the various details
of each instruction, such as the bit format, argument details etc. An example of the format of text is:
00011000 3 JP v8_rel @ read: write: sideeffects;
:param text:
"""
bit_format, effect_format = text.split('@', 2) #the bit_format is the format such as bit pattern, cycles and name
# the effect_format is what registers it effects both for read and write
items = bit_format.split(None, 3)
self.bitPattern = items[0]
self.cycles = int(items[1])
self.name = items[2];
operandText = ""; #operands are the arguments/parameters to the opcode (not all opcode have them)
if len(items) >= 4:
operandText = items[3]
if not operandText:
self.operands = []
else:
self.operands = [x.strip() for x in operandText.split(", ")]
if "v16" in operandText: #check if 16 bit opcode arguments
self.argSize = 2;
elif "v8" in operandText: #check if 8 bit opcode arguments
self.argSize = 1;
else:
self.argSize = 0; #otherwise no opcode arguments (e.g NOP)
assert len(self.bitPattern) == 8 #make sure we haven't missed a bit in the bit pattern
self.effect = OpcodeEffect(effect_format) #the effect on running the opcode (register/memory changes)
def matchBits(self, opcode):
params = defaultdict(int)
opcode_bits = bin(opcode)[2:].zfill(8)
for (x, y) in zip(self.bitPattern, opcode_bits):
if x in ('0', '1'):
if x != y:
return None
else:
# update according parameter
params[x] <<= 1
params[x] |= int(y)
return params
def match(self, opcode):
return self.matchBits(opcode) is not None
def length(self):
"""
Get the length of this opcode including the arguments, we add 1 since all of the single opcodes use 1 byte for
the opcode and then add the argument size (which is normally 0,8 or 16bits)
:return: The size of the opcode and arguments to the opcode
"""
return 1 + self.argSize
def decode(self, proj, opcodes, addr):
assert len(opcodes) == self.length()
params = self.matchBits(opcodes[0])
argument = 0
if self.argSize == 1:
argument = opcodes[1]
elif self.argSize == 2:
argument = (opcodes[2] << 8) | opcodes[1];
next_addr = addr.offset(self.length())
out_operands = [
fillOperand(text, params, argument, next_addr) for text in self.operands
]
reads, writes, values, loads = self.effect.filled(params, make_context(params, argument, next_addr))
return instruction.make(proj, self.name, out_operands, addr, reads, writes, values, loads), next_addr