isa_parser.py

来自「M5,一个功能强大的多处理器系统模拟器.很多针对处理器架构,性能的研究都使用它作」· Python 代码 · 共 1,867 行 · 第 1/5 页

        return ''

    def makeWrite(self):
        return ''

    # Return the memory access size *in bits*, suitable for
    # forming a type via "uint%d_t".  Divide by 8 if you want bytes.
    def makeAccSize(self):
        return self.size

class UPCOperand(Operand):
    def makeConstructor(self):
        return ''

    def makeRead(self):
        return '%s = xc->readMicroPC();\n' % self.base_name

    def makeWrite(self):
        return 'xc->setMicroPC(%s);\n' % self.base_name

class NUPCOperand(Operand):
    def makeConstructor(self):
        return ''

    def makeRead(self):
        return '%s = xc->readNextMicroPC();\n' % self.base_name

    def makeWrite(self):
        return 'xc->setNextMicroPC(%s);\n' % self.base_name

class NPCOperand(Operand):
    def makeConstructor(self):
        return ''

    def makeRead(self):
        return '%s = xc->readNextPC();\n' % self.base_name

    def makeWrite(self):
        return 'xc->setNextPC(%s);\n' % self.base_name

class NNPCOperand(Operand):
    def makeConstructor(self):
        return ''

    def makeRead(self):
        return '%s = xc->readNextNPC();\n' % self.base_name

    def makeWrite(self):
        return 'xc->setNextNPC(%s);\n' % self.base_name

def buildOperandNameMap(userDict, lineno):
    global operandNameMap
    operandNameMap = {}
    for (op_name, val) in userDict.iteritems():
        (base_cls_name, dflt_ext, reg_spec, flags, sort_pri) = val
        (dflt_size, dflt_ctype, dflt_is_signed) = operandTypeMap[dflt_ext]
        # Canonical flag structure is a triple of lists, where each list
        # indicates the set of flags implied by this operand always, when
        # used as a source, and when used as a dest, respectively.
        # For simplicity this can be initialized using a variety of fairly
        # obvious shortcuts; we convert these to canonical form here.
        if not flags:
            # no flags specified (e.g., 'None')
            flags = ( [], [], [] )
        elif isinstance(flags, str):
            # a single flag: assumed to be unconditional
            flags = ( [ flags ], [], [] )
        elif isinstance(flags, list):
            # a list of flags: also assumed to be unconditional
            flags = ( flags, [], [] )
        elif isinstance(flags, tuple):
            # it's a tuple: it should be a triple,
            # but each item could be a single string or a list
            (uncond_flags, src_flags, dest_flags) = flags
            flags = (makeList(uncond_flags),
                     makeList(src_flags), makeList(dest_flags))
        # Accumulate attributes of new operand class in tmp_dict
        tmp_dict = {}
        for attr in ('dflt_ext', 'reg_spec', 'flags', 'sort_pri',
                     'dflt_size', 'dflt_ctype', 'dflt_is_signed'):
            tmp_dict[attr] = eval(attr)
        tmp_dict['base_name'] = op_name
        # New class name will be e.g. "IntReg_Ra"
        cls_name = base_cls_name + '_' + op_name
        # Evaluate string arg to get class object.  Note that the
        # actual base class for "IntReg" is "IntRegOperand", i.e. we
        # have to append "Operand".
        try:
            base_cls = eval(base_cls_name + 'Operand')
        except NameError:
            error(lineno,
                  'error: unknown operand base class "%s"' % base_cls_name)
        # The following statement creates a new class called
        # <cls_name> as a subclass of <base_cls> with the attributes
        # in tmp_dict, just as if we evaluated a class declaration.
        operandNameMap[op_name] = type(cls_name, (base_cls,), tmp_dict)

    # Define operand variables.
    operands = userDict.keys()

    operandsREString = (r'''
    (?<![\w\.])	     # neg. lookbehind assertion: prevent partial matches
    ((%s)(?:\.(\w+))?)   # match: operand with optional '.' then suffix
    (?![\w\.])	     # neg. lookahead assertion: prevent partial matches
    '''
                        % string.join(operands, '|'))

    global operandsRE
    operandsRE = re.compile(operandsREString, re.MULTILINE|re.VERBOSE)

    # Same as operandsREString, but extension is mandatory, and only two
    # groups are returned (base and ext, not full name as above).
    # Used for subtituting '_' for '.' to make C++ identifiers.
    operandsWithExtREString = (r'(?<![\w\.])(%s)\.(\w+)(?![\w\.])'
                               % string.join(operands, '|'))

    global operandsWithExtRE
    operandsWithExtRE = re.compile(operandsWithExtREString, re.MULTILINE)

maxInstSrcRegs = 0
maxInstDestRegs = 0

class OperandList:

    # Find all the operands in the given code block.  Returns an operand
    # descriptor list (instance of class OperandList).
    def __init__(self, code):
        self.items = []
        self.bases = {}
        # delete comments so we don't match on reg specifiers inside
        code = commentRE.sub('', code)
        # search for operands
        next_pos = 0
        while 1:
            match = operandsRE.search(code, next_pos)
            if not match:
                # no more matches: we're done
                break
            op = match.groups()
            # regexp groups are operand full name, base, and extension
            (op_full, op_base, op_ext) = op
            # if the token following the operand is an assignment, this is
            # a destination (LHS), else it's a source (RHS)
            is_dest = (assignRE.match(code, match.end()) != None)
            is_src = not is_dest
            # see if we've already seen this one
            op_desc = self.find_base(op_base)
            if op_desc:
                if op_desc.ext != op_ext:
                    error(0, 'Inconsistent extensions for operand %s' % \
                          op_base)
                op_desc.is_src = op_desc.is_src or is_src
                op_desc.is_dest = op_desc.is_dest or is_dest
            else:
                # new operand: create new descriptor
                op_desc = operandNameMap[op_base](op_full, op_ext,
                                                  is_src, is_dest)
                self.append(op_desc)
            # start next search after end of current match
            next_pos = match.end()
        self.sort()
        # enumerate source & dest register operands... used in building
        # constructor later
        self.numSrcRegs = 0
        self.numDestRegs = 0
        self.numFPDestRegs = 0
        self.numIntDestRegs = 0
        self.memOperand = None
        for op_desc in self.items:
            if op_desc.isReg():
                if op_desc.is_src:
                    op_desc.src_reg_idx = self.numSrcRegs
                    self.numSrcRegs += 1
                if op_desc.is_dest:
                    op_desc.dest_reg_idx = self.numDestRegs
                    self.numDestRegs += 1
                    if op_desc.isFloatReg():
                        self.numFPDestRegs += 1
                    elif op_desc.isIntReg():
                        self.numIntDestRegs += 1
            elif op_desc.isMem():
                if self.memOperand:
                    error(0, "Code block has more than one memory operand.")
                self.memOperand = op_desc
        global maxInstSrcRegs
        global maxInstDestRegs
        if maxInstSrcRegs < self.numSrcRegs:
            maxInstSrcRegs = self.numSrcRegs
        if maxInstDestRegs < self.numDestRegs:
            maxInstDestRegs = self.numDestRegs
        # now make a final pass to finalize op_desc fields that may depend
        # on the register enumeration
        for op_desc in self.items:
            op_desc.finalize()

    def __len__(self):
        return len(self.items)

    def __getitem__(self, index):
        return self.items[index]

    def append(self, op_desc):
        self.items.append(op_desc)
        self.bases[op_desc.base_name] = op_desc

    def find_base(self, base_name):
        # like self.bases[base_name], but returns None if not found
        # (rather than raising exception)
        return self.bases.get(base_name)

    # internal helper function for concat[Some]Attr{Strings|Lists}
    def __internalConcatAttrs(self, attr_name, filter, result):
        for op_desc in self.items:
            if filter(op_desc):
                result += getattr(op_desc, attr_name)
        return result

    # return a single string that is the concatenation of the (string)
    # values of the specified attribute for all operands
    def concatAttrStrings(self, attr_name):
        return self.__internalConcatAttrs(attr_name, lambda x: 1, '')

    # like concatAttrStrings, but only include the values for the operands
    # for which the provided filter function returns true
    def concatSomeAttrStrings(self, filter, attr_name):
        return self.__internalConcatAttrs(attr_name, filter, '')

    # return a single list that is the concatenation of the (list)
    # values of the specified attribute for all operands
    def concatAttrLists(self, attr_name):
        return self.__internalConcatAttrs(attr_name, lambda x: 1, [])

    # like concatAttrLists, but only include the values for the operands
    # for which the provided filter function returns true
    def concatSomeAttrLists(self, filter, attr_name):
        return self.__internalConcatAttrs(attr_name, filter, [])

    def sort(self):
        self.items.sort(lambda a, b: a.sort_pri - b.sort_pri)

class SubOperandList(OperandList):

    # Find all the operands in the given code block.  Returns an operand
    # descriptor list (instance of class OperandList).
    def __init__(self, code, master_list):
        self.items = []
        self.bases = {}
        # delete comments so we don't match on reg specifiers inside
        code = commentRE.sub('', code)
        # search for operands
        next_pos = 0
        while 1:
            match = operandsRE.search(code, next_pos)
            if not match:
                # no more matches: we're done
                break
            op = match.groups()
            # regexp groups are operand full name, base, and extension
            (op_full, op_base, op_ext) = op
            # find this op in the master list
            op_desc = master_list.find_base(op_base)
            if not op_desc:
                error(0, 'Found operand %s which is not in the master list!' \
                        ' This is an internal error' % \
                          op_base)
            else:
                # See if we've already found this operand
                op_desc = self.find_base(op_base)
                if not op_desc:
                    # if not, add a reference to it to this sub list
                    self.append(master_list.bases[op_base])

            # start next search after end of current match
            next_pos = match.end()
        self.sort()
        self.memOperand = None
        for op_desc in self.items:
            if op_desc.isMem():
                if self.memOperand:
                    error(0, "Code block has more than one memory operand.")
                self.memOperand = op_desc

# Regular expression object to match C++ comments
# (used in findOperands())
commentRE = re.compile(r'//.*\n')

# Regular expression object to match assignment statements
# (used in findOperands())
assignRE = re.compile(r'\s*=(?!=)', re.MULTILINE)

# Munge operand names in code string to make legal C++ variable names.
# This means getting rid of the type extension if any.
# (Will match base_name attribute of Operand object.)
def substMungedOpNames(code):
    return operandsWithExtRE.sub(r'\1', code)

# Fix up code snippets for final substitution in templates.
def mungeSnippet(s):
    if isinstance(s, str):
        return substMungedOpNames(substBitOps(s))
    else:
        return s

def makeFlagConstructor(flag_list):
    if len(flag_list) == 0:
        return ''
    # filter out repeated flags
    flag_list.sort()
    i = 1
    while i < len(flag_list):
        if flag_list[i] == flag_list[i-1]:
            del flag_list[i]
        else:
            i += 1
    pre = '\n\tflags['
    post = '] = true;'
    code = pre + string.join(flag_list, post + pre) + post
    return code

# Assume all instruction flags are of the form 'IsFoo'
instFlagRE = re.compile(r'Is.*')

# OpClass constants end in 'Op' except No_OpClass
opClassRE = re.compile(r'.*Op|No_OpClass')

class InstObjParams:
    def __init__(self, mnem, class_name, base_class = '',
                 snippets = {}, opt_args = []):
        self.mnemonic = mnem
        self.class_name = class_name
        self.base_class = base_class
        if not isinstance(snippets, dict):
            snippets = {'code' : snippets}
        compositeCode = ' '.join(map(str, snippets.values()))
        self.snippets = snippets

        self.operands = OperandList(compositeCode)
        self.constructor = self.operands.concatAttrStrings('constructor')
        self.constructor += \
                 '\n\t_numSrcRegs = %d;' % self.operands.numSrcRegs
        self.constructor += \
                 '\n\t_numDestRegs = %d;' % self.operands.numDestRegs
        self.constructor += \
                 '\n\t_numFPDestRegs = %d;' % self.operands.numFPDestRegs
        self.constructor += \
                 '\n\t_numIntDestRegs = %d;' % self.operands.numIntDestRegs
        self.flags = self.operands.concatAttrLists('flags')

        # Make a basic guess on the operand class (function unit type).
        # These are good enough for most cases, and can be overridden
        # later otherwise.
        if 'IsStore' in self.flags:
            self.op_class = 'MemWriteOp'
        elif 'IsLoad' in self.flags or 'IsPrefetch' in self.flags:
            self.op_class = 'MemReadOp'
        elif 'IsFloating' in self.flags:
            self.op_class = 'FloatAddOp'
        else:
            self.op_class = 'IntAluOp'

        # Optional arguments are assumed to be either StaticInst flags
        # or an OpClass value.  To avoid having to import a complete
        # list of these values to match against, we do it ad-hoc
        # with regexps.
        for oa in opt_args:
            if instFlagRE.match(oa):
                self.flags.append(oa)
            elif opClassRE.match(oa):
                self.op_class = oa
            else:
                error(0, 'InstObjPa