//
// Authors: Gabe Black
-////////////////////////////////////////////////////////////////////
-//
-// Code to "specialize" a microcode sequence to use a particular
-// variety of operands
-//
-
-let {{
- # This code builds up a decode block which decodes based on switchval.
- # vals is a dict which matches case values with what should be decoded to.
- # builder is called on the exploded contents of "vals" values to generate
- # whatever code should be used.
- def doSplitDecode(name, Name, builder, switchVal, vals, default = None):
- header_output = ''
- decoder_output = ''
- decode_block = 'switch(%s) {\n' % switchVal
- exec_output = ''
- for (val, todo) in vals.items():
- (new_header_output,
- new_decoder_output,
- new_decode_block,
- new_exec_output) = builder(name, Name, *todo)
- header_output += new_header_output
- decoder_output += new_decoder_output
- decode_block += '\tcase %s: %s\n' % (val, new_decode_block)
- exec_output += new_exec_output
- if default:
- (new_header_output,
- new_decoder_output,
- new_decode_block,
- new_exec_output) = builder(name, Name, *default)
- header_output += new_header_output
- decoder_output += new_decoder_output
- decode_block += '\tdefault: %s\n' % new_decode_block
- exec_output += new_exec_output
- decode_block += '}\n'
- return (header_output, decoder_output, decode_block, exec_output)
-}};
-
-let {{
- class OpType(object):
- parser = re.compile(r"(?P<tag>[A-Z][A-Z]*)(?P<size>[a-z][a-z]*)|(r(?P<reg>[A-Za-z0-9][A-Za-z0-9]*))")
- def __init__(self, opTypeString):
- match = OpType.parser.search(opTypeString)
- if match == None:
- raise Exception, "Problem parsing operand type %s" % opTypeString
- self.reg = match.group("reg")
- self.tag = match.group("tag")
- self.size = match.group("size")
-
- # This function specializes the given piece of code to use a particular
- # set of argument types described by "opTypes". These are "implemented"
- # in reverse order.
- def specializeInst(name, Name, code, opTypes):
- opNum = len(opTypes) - 1
- while len(opTypes):
- # print "Building a composite op with tags", opTypes
- # print "And code", code
- opNum = len(opTypes) - 1
- # A regular expression to find the operand placeholders we're
- # interested in.
- opRe = re.compile("\\^(?P<operandNum>%d)(?=[^0-9]|$)" % opNum)
-
- # Parse the operand type strign we're working with
- opType = OpType(opTypes[opNum])
-
- if opType.reg:
- #Figure out what to do with fixed register operands
- if opType.reg in ("Ax", "Bx", "Cx", "Dx"):
- code = opRe.sub("%%{INTREG_R%s}" % opType.reg.upper(), code)
- elif opType.reg == "Al":
- # We need a way to specify register width
- code = opRe.sub("%{INTREG_RAX}", code)
- else:
- print "Didn't know how to encode fixed register %s!" % opType.reg
- elif opType.tag == None or opType.size == None:
- raise Exception, "Problem parsing operand tag: %s" % opType.tag
- elif opType.tag in ("C", "D", "G", "P", "S", "T", "V"):
- # Use the "reg" field of the ModRM byte to select the register
- code = opRe.sub("%{(uint8_t)MODRM_REG}", code)
- elif opType.tag in ("E", "Q", "W"):
- # This might refer to memory or to a register. We need to
- # divide it up farther.
- regCode = opRe.sub("%{(uint8_t)MODRM_RM}", code)
- regTypes = copy.copy(opTypes)
- regTypes.pop(-1)
- # This needs to refer to memory, but we'll fill in the details
- # later. It needs to take into account unaligned memory
- # addresses.
- memCode = opRe.sub("%0", code)
- memTypes = copy.copy(opTypes)
- memTypes.pop(-1)
- return doSplitDecode(name, Name, specializeInst, "MODRM_MOD",
- {"3" : (regCode, regTypes)}, (memCode, memTypes))
- elif opType.tag in ("I", "J"):
- # Immediates are already in the instruction, so don't leave in
- # those parameters
- code = opRe.sub("${IMMEDIATE}", code)
- elif opType.tag == "M":
- # This needs to refer to memory, but we'll fill in the details
- # later. It needs to take into account unaligned memory
- # addresses.
- code = opRe.sub("%0", code)
- elif opType.tag in ("PR", "R", "VR"):
- # There should probably be a check here to verify that mod
- # is equal to 11b
- code = opRe.sub("%{(uint8_t)MODRM_RM}", code)
- else:
- raise Exception, "Unrecognized tag %s." % opType.tag
- opTypes.pop(-1)
-
- # At this point, we've built up "code" to have all the necessary extra
- # instructions needed to implement whatever types of operands were
- # specified. Now we'll assemble it it into a StaticInst.
- return assembleMicro(name, Name, code)
-}};
-
////////////////////////////////////////////////////////////////////
//
// The microcode assembler