gem5/src/arch/isa_parser.py

2082 lines
76 KiB
Python
Executable file

# Copyright (c) 2003-2005 The Regents of The University of Michigan
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met: redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer;
# redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution;
# neither the name of the copyright holders nor the names of its
# contributors may be used to endorse or promote products derived from
# this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#
# Authors: Steve Reinhardt
import os
import sys
import re
import string
import inspect, traceback
# get type names
from types import *
from m5.util.grammar import Grammar
debug=False
###################
# Utility functions
#
# Indent every line in string 's' by two spaces
# (except preprocessor directives).
# Used to make nested code blocks look pretty.
#
def indent(s):
return re.sub(r'(?m)^(?!#)', ' ', s)
#
# Munge a somewhat arbitrarily formatted piece of Python code
# (e.g. from a format 'let' block) into something whose indentation
# will get by the Python parser.
#
# The two keys here are that Python will give a syntax error if
# there's any whitespace at the beginning of the first line, and that
# all lines at the same lexical nesting level must have identical
# indentation. Unfortunately the way code literals work, an entire
# let block tends to have some initial indentation. Rather than
# trying to figure out what that is and strip it off, we prepend 'if
# 1:' to make the let code the nested block inside the if (and have
# the parser automatically deal with the indentation for us).
#
# We don't want to do this if (1) the code block is empty or (2) the
# first line of the block doesn't have any whitespace at the front.
def fixPythonIndentation(s):
# get rid of blank lines first
s = re.sub(r'(?m)^\s*\n', '', s);
if (s != '' and re.match(r'[ \t]', s[0])):
s = 'if 1:\n' + s
return s
class ISAParserError(Exception):
"""Error handler for parser errors"""
def __init__(self, first, second=None):
if second is None:
self.lineno = 0
self.string = first
else:
if hasattr(first, 'lexer'):
first = first.lexer.lineno
self.lineno = first
self.string = second
def display(self, filename_stack, print_traceback=debug):
# Output formatted to work under Emacs compile-mode. Optional
# 'print_traceback' arg, if set to True, prints a Python stack
# backtrace too (can be handy when trying to debug the parser
# itself).
spaces = ""
for (filename, line) in filename_stack[:-1]:
print "%sIn file included from %s:" % (spaces, filename)
spaces += " "
# Print a Python stack backtrace if requested.
if print_traceback or not self.lineno:
traceback.print_exc()
line_str = "%s:" % (filename_stack[-1][0], )
if self.lineno:
line_str += "%d:" % (self.lineno, )
return "%s%s %s" % (spaces, line_str, self.string)
def exit(self, filename_stack, print_traceback=debug):
# Just call exit.
sys.exit(self.display(filename_stack, print_traceback))
def error(*args):
raise ISAParserError(*args)
####################
# Template objects.
#
# Template objects are format strings that allow substitution from
# the attribute spaces of other objects (e.g. InstObjParams instances).
labelRE = re.compile(r'(?<!%)%\(([^\)]+)\)[sd]')
class Template(object):
def __init__(self, parser, t):
self.parser = parser
self.template = t
def subst(self, d):
myDict = None
# Protect non-Python-dict substitutions (e.g. if there's a printf
# in the templated C++ code)
template = self.parser.protectNonSubstPercents(self.template)
# CPU-model-specific substitutions are handled later (in GenCode).
template = self.parser.protectCpuSymbols(template)
# Build a dict ('myDict') to use for the template substitution.
# Start with the template namespace. Make a copy since we're
# going to modify it.
myDict = self.parser.templateMap.copy()
if isinstance(d, InstObjParams):
# If we're dealing with an InstObjParams object, we need
# to be a little more sophisticated. The instruction-wide
# parameters are already formed, but the parameters which
# are only function wide still need to be generated.
compositeCode = ''
myDict.update(d.__dict__)
# The "operands" and "snippets" attributes of the InstObjParams
# objects are for internal use and not substitution.
del myDict['operands']
del myDict['snippets']
snippetLabels = [l for l in labelRE.findall(template)
if d.snippets.has_key(l)]
snippets = dict([(s, self.parser.mungeSnippet(d.snippets[s]))
for s in snippetLabels])
myDict.update(snippets)
compositeCode = ' '.join(map(str, snippets.values()))
# Add in template itself in case it references any
# operands explicitly (like Mem)
compositeCode += ' ' + template
operands = SubOperandList(self.parser, compositeCode, d.operands)
myDict['op_decl'] = operands.concatAttrStrings('op_decl')
is_src = lambda op: op.is_src
is_dest = lambda op: op.is_dest
myDict['op_src_decl'] = \
operands.concatSomeAttrStrings(is_src, 'op_src_decl')
myDict['op_dest_decl'] = \
operands.concatSomeAttrStrings(is_dest, 'op_dest_decl')
myDict['op_rd'] = operands.concatAttrStrings('op_rd')
myDict['op_wb'] = operands.concatAttrStrings('op_wb')
if d.operands.memOperand:
myDict['mem_acc_size'] = d.operands.memOperand.mem_acc_size
myDict['mem_acc_type'] = d.operands.memOperand.mem_acc_type
elif isinstance(d, dict):
# if the argument is a dictionary, we just use it.
myDict.update(d)
elif hasattr(d, '__dict__'):
# if the argument is an object, we use its attribute map.
myDict.update(d.__dict__)
else:
raise TypeError, "Template.subst() arg must be or have dictionary"
return template % myDict
# Convert to string. This handles the case when a template with a
# CPU-specific term gets interpolated into another template or into
# an output block.
def __str__(self):
return self.parser.expandCpuSymbolsToString(self.template)
################
# Format object.
#
# A format object encapsulates an instruction format. It must provide
# a defineInst() method that generates the code for an instruction
# definition.
class Format(object):
def __init__(self, id, params, code):
self.id = id
self.params = params
label = 'def format ' + id
self.user_code = compile(fixPythonIndentation(code), label, 'exec')
param_list = string.join(params, ", ")
f = '''def defInst(_code, _context, %s):
my_locals = vars().copy()
exec _code in _context, my_locals
return my_locals\n''' % param_list
c = compile(f, label + ' wrapper', 'exec')
exec c
self.func = defInst
def defineInst(self, parser, name, args, lineno):
parser.updateExportContext()
context = parser.exportContext.copy()
if len(name):
Name = name[0].upper()
if len(name) > 1:
Name += name[1:]
context.update({ 'name' : name, 'Name' : Name })
try:
vars = self.func(self.user_code, context, *args[0], **args[1])
except Exception, exc:
if debug:
raise
error(lineno, 'error defining "%s": %s.' % (name, exc))
for k in vars.keys():
if k not in ('header_output', 'decoder_output',
'exec_output', 'decode_block'):
del vars[k]
return GenCode(parser, **vars)
# Special null format to catch an implicit-format instruction
# definition outside of any format block.
class NoFormat(object):
def __init__(self):
self.defaultInst = ''
def defineInst(self, parser, name, args, lineno):
error(lineno,
'instruction definition "%s" with no active format!' % name)
###############
# GenCode class
#
# The GenCode class encapsulates generated code destined for various
# output files. The header_output and decoder_output attributes are
# strings containing code destined for decoder.hh and decoder.cc
# respectively. The decode_block attribute contains code to be
# incorporated in the decode function itself (that will also end up in
# decoder.cc). The exec_output attribute is a dictionary with a key
# for each CPU model name; the value associated with a particular key
# is the string of code for that CPU model's exec.cc file. The
# has_decode_default attribute is used in the decode block to allow
# explicit default clauses to override default default clauses.
class GenCode(object):
# Constructor. At this point we substitute out all CPU-specific
# symbols. For the exec output, these go into the per-model
# dictionary. For all other output types they get collapsed into
# a single string.
def __init__(self, parser,
header_output = '', decoder_output = '', exec_output = '',
decode_block = '', has_decode_default = False):
self.parser = parser
self.header_output = parser.expandCpuSymbolsToString(header_output)
self.decoder_output = parser.expandCpuSymbolsToString(decoder_output)
if isinstance(exec_output, dict):
self.exec_output = exec_output
elif isinstance(exec_output, str):
# If the exec_output arg is a single string, we replicate
# it for each of the CPU models, substituting and
# %(CPU_foo)s params appropriately.
self.exec_output = parser.expandCpuSymbolsToDict(exec_output)
self.decode_block = parser.expandCpuSymbolsToString(decode_block)
self.has_decode_default = has_decode_default
# Override '+' operator: generate a new GenCode object that
# concatenates all the individual strings in the operands.
def __add__(self, other):
exec_output = {}
for cpu in self.parser.cpuModels:
n = cpu.name
exec_output[n] = self.exec_output[n] + other.exec_output[n]
return GenCode(self.parser,
self.header_output + other.header_output,
self.decoder_output + other.decoder_output,
exec_output,
self.decode_block + other.decode_block,
self.has_decode_default or other.has_decode_default)
# Prepend a string (typically a comment) to all the strings.
def prepend_all(self, pre):
self.header_output = pre + self.header_output
self.decoder_output = pre + self.decoder_output
self.decode_block = pre + self.decode_block
for cpu in self.parser.cpuModels:
self.exec_output[cpu.name] = pre + self.exec_output[cpu.name]
# Wrap the decode block in a pair of strings (e.g., 'case foo:'
# and 'break;'). Used to build the big nested switch statement.
def wrap_decode_block(self, pre, post = ''):
self.decode_block = pre + indent(self.decode_block) + post
#####################################################################
#
# Bitfield Operator Support
#
#####################################################################
bitOp1ArgRE = re.compile(r'<\s*(\w+)\s*:\s*>')
bitOpWordRE = re.compile(r'(?<![\w\.])([\w\.]+)<\s*(\w+)\s*:\s*(\w+)\s*>')
bitOpExprRE = re.compile(r'\)<\s*(\w+)\s*:\s*(\w+)\s*>')
def substBitOps(code):
# first convert single-bit selectors to two-index form
# i.e., <n> --> <n:n>
code = bitOp1ArgRE.sub(r'<\1:\1>', code)
# simple case: selector applied to ID (name)
# i.e., foo<a:b> --> bits(foo, a, b)
code = bitOpWordRE.sub(r'bits(\1, \2, \3)', code)
# if selector is applied to expression (ending in ')'),
# we need to search backward for matching '('
match = bitOpExprRE.search(code)
while match:
exprEnd = match.start()
here = exprEnd - 1
nestLevel = 1
while nestLevel > 0:
if code[here] == '(':
nestLevel -= 1
elif code[here] == ')':
nestLevel += 1
here -= 1
if here < 0:
sys.exit("Didn't find '('!")
exprStart = here+1
newExpr = r'bits(%s, %s, %s)' % (code[exprStart:exprEnd+1],
match.group(1), match.group(2))
code = code[:exprStart] + newExpr + code[match.end():]
match = bitOpExprRE.search(code)
return code
#####################################################################
#
# Code Parser
#
# The remaining code is the support for automatically extracting
# instruction characteristics from pseudocode.
#
#####################################################################
# Force the argument to be a list. Useful for flags, where a caller
# can specify a singleton flag or a list of flags. Also usful for
# converting tuples to lists so they can be modified.
def makeList(arg):
if isinstance(arg, list):
return arg
elif isinstance(arg, tuple):
return list(arg)
elif not arg:
return []
else:
return [ arg ]
class Operand(object):
'''Base class for operand descriptors. An instance of this class
(or actually a class derived from this one) represents a specific
operand for a code block (e.g, "Rc.sq" as a dest). Intermediate
derived classes encapsulates the traits of a particular operand
type (e.g., "32-bit integer register").'''
def buildReadCode(self, func = None):
subst_dict = {"name": self.base_name,
"func": func,
"reg_idx": self.reg_spec,
"size": self.size,
"ctype": self.ctype}
if hasattr(self, 'src_reg_idx'):
subst_dict['op_idx'] = self.src_reg_idx
code = self.read_code % subst_dict
if self.size != self.dflt_size:
return '%s = bits(%s, %d, 0);\n' % \
(self.base_name, code, self.size-1)
else:
return '%s = %s;\n' % \
(self.base_name, code)
def buildWriteCode(self, func = None):
if (self.size != self.dflt_size and self.is_signed):
final_val = 'sext<%d>(%s)' % (self.size, self.base_name)
else:
final_val = self.base_name
subst_dict = {"name": self.base_name,
"func": func,
"reg_idx": self.reg_spec,
"size": self.size,
"ctype": self.ctype,
"final_val": final_val}
if hasattr(self, 'dest_reg_idx'):
subst_dict['op_idx'] = self.dest_reg_idx
code = self.write_code % subst_dict
return '''
{
%s final_val = %s;
%s;
if (traceData) { traceData->setData(final_val); }
}''' % (self.dflt_ctype, final_val, code)
def __init__(self, parser, full_name, ext, is_src, is_dest):
self.full_name = full_name
self.ext = ext
self.is_src = is_src
self.is_dest = is_dest
# The 'effective extension' (eff_ext) is either the actual
# extension, if one was explicitly provided, or the default.
if ext:
self.eff_ext = ext
else:
self.eff_ext = self.dflt_ext
self.size, self.ctype, self.is_signed = \
parser.operandTypeMap[self.eff_ext]
# note that mem_acc_size is undefined for non-mem operands...
# template must be careful not to use it if it doesn't apply.
if self.isMem():
self.mem_acc_size = self.makeAccSize()
if self.ctype in ['Twin32_t', 'Twin64_t']:
self.mem_acc_type = 'Twin'
else:
self.mem_acc_type = 'uint'
# Finalize additional fields (primarily code fields). This step
# is done separately since some of these fields may depend on the
# register index enumeration that hasn't been performed yet at the
# time of __init__().
def finalize(self):
self.flags = self.getFlags()
self.constructor = self.makeConstructor()
self.op_decl = self.makeDecl()
if self.is_src:
self.op_rd = self.makeRead()
self.op_src_decl = self.makeDecl()
else:
self.op_rd = ''
self.op_src_decl = ''
if self.is_dest:
self.op_wb = self.makeWrite()
self.op_dest_decl = self.makeDecl()
else:
self.op_wb = ''
self.op_dest_decl = ''
def isMem(self):
return 0
def isReg(self):
return 0
def isFloatReg(self):
return 0
def isIntReg(self):
return 0
def isControlReg(self):
return 0
def getFlags(self):
# note the empty slice '[:]' gives us a copy of self.flags[0]
# instead of a reference to it
my_flags = self.flags[0][:]
if self.is_src:
my_flags += self.flags[1]
if self.is_dest:
my_flags += self.flags[2]
return my_flags
def makeDecl(self):
# Note that initializations in the declarations are solely
# to avoid 'uninitialized variable' errors from the compiler.
return self.ctype + ' ' + self.base_name + ' = 0;\n';
class IntRegOperand(Operand):
def isReg(self):
return 1
def isIntReg(self):
return 1
def makeConstructor(self):
c = ''
if self.is_src:
c += '\n\t_srcRegIdx[%d] = %s;' % \
(self.src_reg_idx, self.reg_spec)
if self.is_dest:
c += '\n\t_destRegIdx[%d] = %s;' % \
(self.dest_reg_idx, self.reg_spec)
return c
def makeRead(self):
if (self.ctype == 'float' or self.ctype == 'double'):
error('Attempt to read integer register as FP')
if self.read_code != None:
return self.buildReadCode('readIntRegOperand')
if (self.size == self.dflt_size):
return '%s = xc->readIntRegOperand(this, %d);\n' % \
(self.base_name, self.src_reg_idx)
elif (self.size > self.dflt_size):
int_reg_val = 'xc->readIntRegOperand(this, %d)' % \
(self.src_reg_idx)
if (self.is_signed):
int_reg_val = 'sext<%d>(%s)' % (self.dflt_size, int_reg_val)
return '%s = %s;\n' % (self.base_name, int_reg_val)
else:
return '%s = bits(xc->readIntRegOperand(this, %d), %d, 0);\n' % \
(self.base_name, self.src_reg_idx, self.size-1)
def makeWrite(self):
if (self.ctype == 'float' or self.ctype == 'double'):
error('Attempt to write integer register as FP')
if self.write_code != None:
return self.buildWriteCode('setIntRegOperand')
if (self.size != self.dflt_size and self.is_signed):
final_val = 'sext<%d>(%s)' % (self.size, self.base_name)
else:
final_val = self.base_name
wb = '''
{
%s final_val = %s;
xc->setIntRegOperand(this, %d, final_val);\n
if (traceData) { traceData->setData(final_val); }
}''' % (self.dflt_ctype, final_val, self.dest_reg_idx)
return wb
class FloatRegOperand(Operand):
def isReg(self):
return 1
def isFloatReg(self):
return 1
def makeConstructor(self):
c = ''
if self.is_src:
c += '\n\t_srcRegIdx[%d] = %s + FP_Base_DepTag;' % \
(self.src_reg_idx, self.reg_spec)
if self.is_dest:
c += '\n\t_destRegIdx[%d] = %s + FP_Base_DepTag;' % \
(self.dest_reg_idx, self.reg_spec)
return c
def makeRead(self):
bit_select = 0
if (self.ctype == 'float' or self.ctype == 'double'):
func = 'readFloatRegOperand'
else:
func = 'readFloatRegOperandBits'
if (self.size != self.dflt_size):
bit_select = 1
base = 'xc->%s(this, %d)' % (func, self.src_reg_idx)
if self.read_code != None:
return self.buildReadCode(func)
if bit_select:
return '%s = bits(%s, %d, 0);\n' % \
(self.base_name, base, self.size-1)
else:
return '%s = %s;\n' % (self.base_name, base)
def makeWrite(self):
final_val = self.base_name
final_ctype = self.ctype
if (self.ctype == 'float' or self.ctype == 'double'):
func = 'setFloatRegOperand'
elif (self.ctype == 'uint32_t' or self.ctype == 'uint64_t'):
func = 'setFloatRegOperandBits'
else:
func = 'setFloatRegOperandBits'
final_ctype = 'uint%d_t' % self.dflt_size
if (self.size != self.dflt_size and self.is_signed):
final_val = 'sext<%d>(%s)' % (self.size, self.base_name)
if self.write_code != None:
return self.buildWriteCode(func)
wb = '''
{
%s final_val = %s;
xc->%s(this, %d, final_val);\n
if (traceData) { traceData->setData(final_val); }
}''' % (final_ctype, final_val, func, self.dest_reg_idx)
return wb
class ControlRegOperand(Operand):
def isReg(self):
return 1
def isControlReg(self):
return 1
def makeConstructor(self):
c = ''
if self.is_src:
c += '\n\t_srcRegIdx[%d] = %s + Ctrl_Base_DepTag;' % \
(self.src_reg_idx, self.reg_spec)
if self.is_dest:
c += '\n\t_destRegIdx[%d] = %s + Ctrl_Base_DepTag;' % \
(self.dest_reg_idx, self.reg_spec)
return c
def makeRead(self):
bit_select = 0
if (self.ctype == 'float' or self.ctype == 'double'):
error('Attempt to read control register as FP')
if self.read_code != None:
return self.buildReadCode('readMiscRegOperand')
base = 'xc->readMiscRegOperand(this, %s)' % self.src_reg_idx
if self.size == self.dflt_size:
return '%s = %s;\n' % (self.base_name, base)
else:
return '%s = bits(%s, %d, 0);\n' % \
(self.base_name, base, self.size-1)
def makeWrite(self):
if (self.ctype == 'float' or self.ctype == 'double'):
error('Attempt to write control register as FP')
if self.write_code != None:
return self.buildWriteCode('setMiscRegOperand')
wb = 'xc->setMiscRegOperand(this, %s, %s);\n' % \
(self.dest_reg_idx, self.base_name)
wb += 'if (traceData) { traceData->setData(%s); }' % \
self.base_name
return wb
class MemOperand(Operand):
def isMem(self):
return 1
def makeConstructor(self):
return ''
def makeDecl(self):
# Note that initializations in the declarations are solely
# to avoid 'uninitialized variable' errors from the compiler.
# Declare memory data variable.
if self.ctype in ['Twin32_t','Twin64_t']:
return "%s %s; %s.a = 0; %s.b = 0;\n" % \
(self.ctype, self.base_name, self.base_name, self.base_name)
return '%s %s = 0;\n' % (self.ctype, self.base_name)
def makeRead(self):
if self.read_code != None:
return self.buildReadCode()
return ''
def makeWrite(self):
if self.write_code != None:
return self.buildWriteCode()
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 PCOperand(Operand):
def makeConstructor(self):
return ''
def makeRead(self):
return '%s = xc->readPC();\n' % self.base_name
def makeWrite(self):
return 'xc->setPC(%s);\n' % self.base_name
class UPCOperand(Operand):
def makeConstructor(self):
return ''
def makeRead(self):
if self.read_code != None:
return self.buildReadCode('readMicroPC')
return '%s = xc->readMicroPC();\n' % self.base_name
def makeWrite(self):
if self.write_code != None:
return self.buildWriteCode('setMicroPC')
return 'xc->setMicroPC(%s);\n' % self.base_name
class NUPCOperand(Operand):
def makeConstructor(self):
return ''
def makeRead(self):
if self.read_code != None:
return self.buildReadCode('readNextMicroPC')
return '%s = xc->readNextMicroPC();\n' % self.base_name
def makeWrite(self):
if self.write_code != None:
return self.buildWriteCode('setNextMicroPC')
return 'xc->setNextMicroPC(%s);\n' % self.base_name
class NPCOperand(Operand):
def makeConstructor(self):
return ''
def makeRead(self):
if self.read_code != None:
return self.buildReadCode('readNextPC')
return '%s = xc->readNextPC();\n' % self.base_name
def makeWrite(self):
if self.write_code != None:
return self.buildWriteCode('setNextPC')
return 'xc->setNextPC(%s);\n' % self.base_name
class NNPCOperand(Operand):
def makeConstructor(self):
return ''
def makeRead(self):
if self.read_code != None:
return self.buildReadCode('readNextNPC')
return '%s = xc->readNextNPC();\n' % self.base_name
def makeWrite(self):
if self.write_code != None:
return self.buildWriteCode('setNextNPC')
return 'xc->setNextNPC(%s);\n' % self.base_name
class OperandList(object):
'''Find all the operands in the given code block. Returns an operand
descriptor list (instance of class OperandList).'''
def __init__(self, parser, 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 = parser.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('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 = parser.operandNameMap[op_base](parser,
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("Code block has more than one memory operand.")
self.memOperand = op_desc
if parser.maxInstSrcRegs < self.numSrcRegs:
parser.maxInstSrcRegs = self.numSrcRegs
if parser.maxInstDestRegs < self.numDestRegs:
parser.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, parser, 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 = parser.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('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("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)
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(object):
def __init__(self, parser, 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(parser, 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('InstObjParams: optional arg "%s" not recognized '
'as StaticInst::Flag or OpClass.' % oa)
# add flag initialization to contructor here to include
# any flags added via opt_args
self.constructor += makeFlagConstructor(self.flags)
# if 'IsFloating' is set, add call to the FP enable check
# function (which should be provided by isa_desc via a declare)
if 'IsFloating' in self.flags:
self.fp_enable_check = 'fault = checkFpEnableFault(xc);'
else:
self.fp_enable_check = ''
##############
# Stack: a simple stack object. Used for both formats (formatStack)
# and default cases (defaultStack). Simply wraps a list to give more
# stack-like syntax and enable initialization with an argument list
# (as opposed to an argument that's a list).
class Stack(list):
def __init__(self, *items):
list.__init__(self, items)
def push(self, item):
self.append(item);
def top(self):
return self[-1]
#######################
#
# Output file template
#
file_template = '''
/*
* DO NOT EDIT THIS FILE!!!
*
* It was automatically generated from the ISA description in %(filename)s
*/
%(includes)s
%(global_output)s
namespace %(namespace)s {
%(namespace_output)s
} // namespace %(namespace)s
%(decode_function)s
'''
max_inst_regs_template = '''
/*
* DO NOT EDIT THIS FILE!!!
*
* It was automatically generated from the ISA description in %(filename)s
*/
namespace %(namespace)s {
const int MaxInstSrcRegs = %(MaxInstSrcRegs)d;
const int MaxInstDestRegs = %(MaxInstDestRegs)d;
} // namespace %(namespace)s
'''
class ISAParser(Grammar):
def __init__(self, output_dir, cpu_models):
super(ISAParser, self).__init__()
self.output_dir = output_dir
self.cpuModels = cpu_models
# variable to hold templates
self.templateMap = {}
# This dictionary maps format name strings to Format objects.
self.formatMap = {}
# The format stack.
self.formatStack = Stack(NoFormat())
# The default case stack.
self.defaultStack = Stack(None)
# Stack that tracks current file and line number. Each
# element is a tuple (filename, lineno) that records the
# *current* filename and the line number in the *previous*
# file where it was included.
self.fileNameStack = Stack()
symbols = ('makeList', 're', 'string')
self.exportContext = dict([(s, eval(s)) for s in symbols])
self.maxInstSrcRegs = 0
self.maxInstDestRegs = 0
#####################################################################
#
# Lexer
#
# The PLY lexer module takes two things as input:
# - A list of token names (the string list 'tokens')
# - A regular expression describing a match for each token. The
# regexp for token FOO can be provided in two ways:
# - as a string variable named t_FOO
# - as the doc string for a function named t_FOO. In this case,
# the function is also executed, allowing an action to be
# associated with each token match.
#
#####################################################################
# Reserved words. These are listed separately as they are matched
# using the same regexp as generic IDs, but distinguished in the
# t_ID() function. The PLY documentation suggests this approach.
reserved = (
'BITFIELD', 'DECODE', 'DECODER', 'DEFAULT', 'DEF', 'EXEC', 'FORMAT',
'HEADER', 'LET', 'NAMESPACE', 'OPERAND_TYPES', 'OPERANDS',
'OUTPUT', 'SIGNED', 'TEMPLATE'
)
# List of tokens. The lex module requires this.
tokens = reserved + (
# identifier
'ID',
# integer literal
'INTLIT',
# string literal
'STRLIT',
# code literal
'CODELIT',
# ( ) [ ] { } < > , ; . : :: *
'LPAREN', 'RPAREN',
'LBRACKET', 'RBRACKET',
'LBRACE', 'RBRACE',
'LESS', 'GREATER', 'EQUALS',
'COMMA', 'SEMI', 'DOT', 'COLON', 'DBLCOLON',
'ASTERISK',
# C preprocessor directives
'CPPDIRECTIVE'
# The following are matched but never returned. commented out to
# suppress PLY warning
# newfile directive
# 'NEWFILE',
# endfile directive
# 'ENDFILE'
)
# Regular expressions for token matching
t_LPAREN = r'\('
t_RPAREN = r'\)'
t_LBRACKET = r'\['
t_RBRACKET = r'\]'
t_LBRACE = r'\{'
t_RBRACE = r'\}'
t_LESS = r'\<'
t_GREATER = r'\>'
t_EQUALS = r'='
t_COMMA = r','
t_SEMI = r';'
t_DOT = r'\.'
t_COLON = r':'
t_DBLCOLON = r'::'
t_ASTERISK = r'\*'
# Identifiers and reserved words
reserved_map = { }
for r in reserved:
reserved_map[r.lower()] = r
def t_ID(self, t):
r'[A-Za-z_]\w*'
t.type = self.reserved_map.get(t.value, 'ID')
return t
# Integer literal
def t_INTLIT(self, t):
r'-?(0x[\da-fA-F]+)|\d+'
try:
t.value = int(t.value,0)
except ValueError:
error(t, 'Integer value "%s" too large' % t.value)
t.value = 0
return t
# String literal. Note that these use only single quotes, and
# can span multiple lines.
def t_STRLIT(self, t):
r"(?m)'([^'])+'"
# strip off quotes
t.value = t.value[1:-1]
t.lexer.lineno += t.value.count('\n')
return t
# "Code literal"... like a string literal, but delimiters are
# '{{' and '}}' so they get formatted nicely under emacs c-mode
def t_CODELIT(self, t):
r"(?m)\{\{([^\}]|}(?!\}))+\}\}"
# strip off {{ & }}
t.value = t.value[2:-2]
t.lexer.lineno += t.value.count('\n')
return t
def t_CPPDIRECTIVE(self, t):
r'^\#[^\#].*\n'
t.lexer.lineno += t.value.count('\n')
return t
def t_NEWFILE(self, t):
r'^\#\#newfile\s+"[\w/.-]*"'
self.fileNameStack.push((t.value[11:-1], t.lexer.lineno))
t.lexer.lineno = 0
def t_ENDFILE(self, t):
r'^\#\#endfile'
(old_filename, t.lexer.lineno) = self.fileNameStack.pop()
#
# The functions t_NEWLINE, t_ignore, and t_error are
# special for the lex module.
#
# Newlines
def t_NEWLINE(self, t):
r'\n+'
t.lexer.lineno += t.value.count('\n')
# Comments
def t_comment(self, t):
r'//.*'
# Completely ignored characters
t_ignore = ' \t\x0c'
# Error handler
def t_error(self, t):
error(t, "illegal character '%s'" % t.value[0])
t.skip(1)
#####################################################################
#
# Parser
#
# Every function whose name starts with 'p_' defines a grammar
# rule. The rule is encoded in the function's doc string, while
# the function body provides the action taken when the rule is
# matched. The argument to each function is a list of the values
# of the rule's symbols: t[0] for the LHS, and t[1..n] for the
# symbols on the RHS. For tokens, the value is copied from the
# t.value attribute provided by the lexer. For non-terminals, the
# value is assigned by the producing rule; i.e., the job of the
# grammar rule function is to set the value for the non-terminal
# on the LHS (by assigning to t[0]).
#####################################################################
# The LHS of the first grammar rule is used as the start symbol
# (in this case, 'specification'). Note that this rule enforces
# that there will be exactly one namespace declaration, with 0 or
# more global defs/decls before and after it. The defs & decls
# before the namespace decl will be outside the namespace; those
# after will be inside. The decoder function is always inside the
# namespace.
def p_specification(self, t):
'specification : opt_defs_and_outputs name_decl opt_defs_and_outputs decode_block'
global_code = t[1]
isa_name = t[2]
namespace = isa_name + "Inst"
# wrap the decode block as a function definition
t[4].wrap_decode_block('''
StaticInstPtr
%(isa_name)s::decodeInst(%(isa_name)s::ExtMachInst machInst)
{
using namespace %(namespace)s;
''' % vars(), '}')
# both the latter output blocks and the decode block are in
# the namespace
namespace_code = t[3] + t[4]
# pass it all back to the caller of yacc.parse()
t[0] = (isa_name, namespace, global_code, namespace_code)
# ISA name declaration looks like "namespace <foo>;"
def p_name_decl(self, t):
'name_decl : NAMESPACE ID SEMI'
t[0] = t[2]
# 'opt_defs_and_outputs' is a possibly empty sequence of
# def and/or output statements.
def p_opt_defs_and_outputs_0(self, t):
'opt_defs_and_outputs : empty'
t[0] = GenCode(self)
def p_opt_defs_and_outputs_1(self, t):
'opt_defs_and_outputs : defs_and_outputs'
t[0] = t[1]
def p_defs_and_outputs_0(self, t):
'defs_and_outputs : def_or_output'
t[0] = t[1]
def p_defs_and_outputs_1(self, t):
'defs_and_outputs : defs_and_outputs def_or_output'
t[0] = t[1] + t[2]
# The list of possible definition/output statements.
def p_def_or_output(self, t):
'''def_or_output : def_format
| def_bitfield
| def_bitfield_struct
| def_template
| def_operand_types
| def_operands
| output_header
| output_decoder
| output_exec
| global_let'''
t[0] = t[1]
# Output blocks 'output <foo> {{...}}' (C++ code blocks) are copied
# directly to the appropriate output section.
# Massage output block by substituting in template definitions and
# bit operators. We handle '%'s embedded in the string that don't
# indicate template substitutions (or CPU-specific symbols, which
# get handled in GenCode) by doubling them first so that the
# format operation will reduce them back to single '%'s.
def process_output(self, s):
s = self.protectNonSubstPercents(s)
# protects cpu-specific symbols too
s = self.protectCpuSymbols(s)
return substBitOps(s % self.templateMap)
def p_output_header(self, t):
'output_header : OUTPUT HEADER CODELIT SEMI'
t[0] = GenCode(self, header_output = self.process_output(t[3]))
def p_output_decoder(self, t):
'output_decoder : OUTPUT DECODER CODELIT SEMI'
t[0] = GenCode(self, decoder_output = self.process_output(t[3]))
def p_output_exec(self, t):
'output_exec : OUTPUT EXEC CODELIT SEMI'
t[0] = GenCode(self, exec_output = self.process_output(t[3]))
# global let blocks 'let {{...}}' (Python code blocks) are
# executed directly when seen. Note that these execute in a
# special variable context 'exportContext' to prevent the code
# from polluting this script's namespace.
def p_global_let(self, t):
'global_let : LET CODELIT SEMI'
self.updateExportContext()
self.exportContext["header_output"] = ''
self.exportContext["decoder_output"] = ''
self.exportContext["exec_output"] = ''
self.exportContext["decode_block"] = ''
try:
exec fixPythonIndentation(t[2]) in self.exportContext
except Exception, exc:
if debug:
raise
error(t, 'error: %s in global let block "%s".' % (exc, t[2]))
t[0] = GenCode(self,
header_output=self.exportContext["header_output"],
decoder_output=self.exportContext["decoder_output"],
exec_output=self.exportContext["exec_output"],
decode_block=self.exportContext["decode_block"])
# Define the mapping from operand type extensions to C++ types and
# bit widths (stored in operandTypeMap).
def p_def_operand_types(self, t):
'def_operand_types : DEF OPERAND_TYPES CODELIT SEMI'
try:
user_dict = eval('{' + t[3] + '}')
except Exception, exc:
if debug:
raise
error(t,
'error: %s in def operand_types block "%s".' % (exc, t[3]))
self.buildOperandTypeMap(user_dict, t.lexer.lineno)
t[0] = GenCode(self) # contributes nothing to the output C++ file
# Define the mapping from operand names to operand classes and
# other traits. Stored in operandNameMap.
def p_def_operands(self, t):
'def_operands : DEF OPERANDS CODELIT SEMI'
if not hasattr(self, 'operandTypeMap'):
error(t, 'error: operand types must be defined before operands')
try:
user_dict = eval('{' + t[3] + '}', self.exportContext)
except Exception, exc:
if debug:
raise
error(t, 'error: %s in def operands block "%s".' % (exc, t[3]))
self.buildOperandNameMap(user_dict, t.lexer.lineno)
t[0] = GenCode(self) # contributes nothing to the output C++ file
# A bitfield definition looks like:
# 'def [signed] bitfield <ID> [<first>:<last>]'
# This generates a preprocessor macro in the output file.
def p_def_bitfield_0(self, t):
'def_bitfield : DEF opt_signed BITFIELD ID LESS INTLIT COLON INTLIT GREATER SEMI'
expr = 'bits(machInst, %2d, %2d)' % (t[6], t[8])
if (t[2] == 'signed'):
expr = 'sext<%d>(%s)' % (t[6] - t[8] + 1, expr)
hash_define = '#undef %s\n#define %s\t%s\n' % (t[4], t[4], expr)
t[0] = GenCode(self, header_output=hash_define)
# alternate form for single bit: 'def [signed] bitfield <ID> [<bit>]'
def p_def_bitfield_1(self, t):
'def_bitfield : DEF opt_signed BITFIELD ID LESS INTLIT GREATER SEMI'
expr = 'bits(machInst, %2d, %2d)' % (t[6], t[6])
if (t[2] == 'signed'):
expr = 'sext<%d>(%s)' % (1, expr)
hash_define = '#undef %s\n#define %s\t%s\n' % (t[4], t[4], expr)
t[0] = GenCode(self, header_output=hash_define)
# alternate form for structure member: 'def bitfield <ID> <ID>'
def p_def_bitfield_struct(self, t):
'def_bitfield_struct : DEF opt_signed BITFIELD ID id_with_dot SEMI'
if (t[2] != ''):
error(t, 'error: structure bitfields are always unsigned.')
expr = 'machInst.%s' % t[5]
hash_define = '#undef %s\n#define %s\t%s\n' % (t[4], t[4], expr)
t[0] = GenCode(self, header_output=hash_define)
def p_id_with_dot_0(self, t):
'id_with_dot : ID'
t[0] = t[1]
def p_id_with_dot_1(self, t):
'id_with_dot : ID DOT id_with_dot'
t[0] = t[1] + t[2] + t[3]
def p_opt_signed_0(self, t):
'opt_signed : SIGNED'
t[0] = t[1]
def p_opt_signed_1(self, t):
'opt_signed : empty'
t[0] = ''
def p_def_template(self, t):
'def_template : DEF TEMPLATE ID CODELIT SEMI'
self.templateMap[t[3]] = Template(self, t[4])
t[0] = GenCode(self)
# An instruction format definition looks like
# "def format <fmt>(<params>) {{...}};"
def p_def_format(self, t):
'def_format : DEF FORMAT ID LPAREN param_list RPAREN CODELIT SEMI'
(id, params, code) = (t[3], t[5], t[7])
self.defFormat(id, params, code, t.lexer.lineno)
t[0] = GenCode(self)
# The formal parameter list for an instruction format is a
# possibly empty list of comma-separated parameters. Positional
# (standard, non-keyword) parameters must come first, followed by
# keyword parameters, followed by a '*foo' parameter that gets
# excess positional arguments (as in Python). Each of these three
# parameter categories is optional.
#
# Note that we do not support the '**foo' parameter for collecting
# otherwise undefined keyword args. Otherwise the parameter list
# is (I believe) identical to what is supported in Python.
#
# The param list generates a tuple, where the first element is a
# list of the positional params and the second element is a dict
# containing the keyword params.
def p_param_list_0(self, t):
'param_list : positional_param_list COMMA nonpositional_param_list'
t[0] = t[1] + t[3]
def p_param_list_1(self, t):
'''param_list : positional_param_list
| nonpositional_param_list'''
t[0] = t[1]
def p_positional_param_list_0(self, t):
'positional_param_list : empty'
t[0] = []
def p_positional_param_list_1(self, t):
'positional_param_list : ID'
t[0] = [t[1]]
def p_positional_param_list_2(self, t):
'positional_param_list : positional_param_list COMMA ID'
t[0] = t[1] + [t[3]]
def p_nonpositional_param_list_0(self, t):
'nonpositional_param_list : keyword_param_list COMMA excess_args_param'
t[0] = t[1] + t[3]
def p_nonpositional_param_list_1(self, t):
'''nonpositional_param_list : keyword_param_list
| excess_args_param'''
t[0] = t[1]
def p_keyword_param_list_0(self, t):
'keyword_param_list : keyword_param'
t[0] = [t[1]]
def p_keyword_param_list_1(self, t):
'keyword_param_list : keyword_param_list COMMA keyword_param'
t[0] = t[1] + [t[3]]
def p_keyword_param(self, t):
'keyword_param : ID EQUALS expr'
t[0] = t[1] + ' = ' + t[3].__repr__()
def p_excess_args_param(self, t):
'excess_args_param : ASTERISK ID'
# Just concatenate them: '*ID'. Wrap in list to be consistent
# with positional_param_list and keyword_param_list.
t[0] = [t[1] + t[2]]
# End of format definition-related rules.
##############
#
# A decode block looks like:
# decode <field1> [, <field2>]* [default <inst>] { ... }
#
def p_decode_block(self, t):
'decode_block : DECODE ID opt_default LBRACE decode_stmt_list RBRACE'
default_defaults = self.defaultStack.pop()
codeObj = t[5]
# use the "default defaults" only if there was no explicit
# default statement in decode_stmt_list
if not codeObj.has_decode_default:
codeObj += default_defaults
codeObj.wrap_decode_block('switch (%s) {\n' % t[2], '}\n')
t[0] = codeObj
# The opt_default statement serves only to push the "default
# defaults" onto defaultStack. This value will be used by nested
# decode blocks, and used and popped off when the current
# decode_block is processed (in p_decode_block() above).
def p_opt_default_0(self, t):
'opt_default : empty'
# no default specified: reuse the one currently at the top of
# the stack
self.defaultStack.push(self.defaultStack.top())
# no meaningful value returned
t[0] = None
def p_opt_default_1(self, t):
'opt_default : DEFAULT inst'
# push the new default
codeObj = t[2]
codeObj.wrap_decode_block('\ndefault:\n', 'break;\n')
self.defaultStack.push(codeObj)
# no meaningful value returned
t[0] = None
def p_decode_stmt_list_0(self, t):
'decode_stmt_list : decode_stmt'
t[0] = t[1]
def p_decode_stmt_list_1(self, t):
'decode_stmt_list : decode_stmt decode_stmt_list'
if (t[1].has_decode_default and t[2].has_decode_default):
error(t, 'Two default cases in decode block')
t[0] = t[1] + t[2]
#
# Decode statement rules
#
# There are four types of statements allowed in a decode block:
# 1. Format blocks 'format <foo> { ... }'
# 2. Nested decode blocks
# 3. Instruction definitions.
# 4. C preprocessor directives.
# Preprocessor directives found in a decode statement list are
# passed through to the output, replicated to all of the output
# code streams. This works well for ifdefs, so we can ifdef out
# both the declarations and the decode cases generated by an
# instruction definition. Handling them as part of the grammar
# makes it easy to keep them in the right place with respect to
# the code generated by the other statements.
def p_decode_stmt_cpp(self, t):
'decode_stmt : CPPDIRECTIVE'
t[0] = GenCode(self, t[1], t[1], t[1], t[1])
# A format block 'format <foo> { ... }' sets the default
# instruction format used to handle instruction definitions inside
# the block. This format can be overridden by using an explicit
# format on the instruction definition or with a nested format
# block.
def p_decode_stmt_format(self, t):
'decode_stmt : FORMAT push_format_id LBRACE decode_stmt_list RBRACE'
# The format will be pushed on the stack when 'push_format_id'
# is processed (see below). Once the parser has recognized
# the full production (though the right brace), we're done
# with the format, so now we can pop it.
self.formatStack.pop()
t[0] = t[4]
# This rule exists so we can set the current format (& push the
# stack) when we recognize the format name part of the format
# block.
def p_push_format_id(self, t):
'push_format_id : ID'
try:
self.formatStack.push(self.formatMap[t[1]])
t[0] = ('', '// format %s' % t[1])
except KeyError:
error(t, 'instruction format "%s" not defined.' % t[1])
# Nested decode block: if the value of the current field matches
# the specified constant, do a nested decode on some other field.
def p_decode_stmt_decode(self, t):
'decode_stmt : case_label COLON decode_block'
label = t[1]
codeObj = t[3]
# just wrap the decoding code from the block as a case in the
# outer switch statement.
codeObj.wrap_decode_block('\n%s:\n' % label)
codeObj.has_decode_default = (label == 'default')
t[0] = codeObj
# Instruction definition (finally!).
def p_decode_stmt_inst(self, t):
'decode_stmt : case_label COLON inst SEMI'
label = t[1]
codeObj = t[3]
codeObj.wrap_decode_block('\n%s:' % label, 'break;\n')
codeObj.has_decode_default = (label == 'default')
t[0] = codeObj
# The case label is either a list of one or more constants or
# 'default'
def p_case_label_0(self, t):
'case_label : intlit_list'
def make_case(intlit):
if intlit >= 2**32:
return 'case ULL(%#x)' % intlit
else:
return 'case %#x' % intlit
t[0] = ': '.join(map(make_case, t[1]))
def p_case_label_1(self, t):
'case_label : DEFAULT'
t[0] = 'default'
#
# The constant list for a decode case label must be non-empty, but
# may have one or more comma-separated integer literals in it.
#
def p_intlit_list_0(self, t):
'intlit_list : INTLIT'
t[0] = [t[1]]
def p_intlit_list_1(self, t):
'intlit_list : intlit_list COMMA INTLIT'
t[0] = t[1]
t[0].append(t[3])
# Define an instruction using the current instruction format
# (specified by an enclosing format block).
# "<mnemonic>(<args>)"
def p_inst_0(self, t):
'inst : ID LPAREN arg_list RPAREN'
# Pass the ID and arg list to the current format class to deal with.
currentFormat = self.formatStack.top()
codeObj = currentFormat.defineInst(self, t[1], t[3], t.lexer.lineno)
args = ','.join(map(str, t[3]))
args = re.sub('(?m)^', '//', args)
args = re.sub('^//', '', args)
comment = '\n// %s::%s(%s)\n' % (currentFormat.id, t[1], args)
codeObj.prepend_all(comment)
t[0] = codeObj
# Define an instruction using an explicitly specified format:
# "<fmt>::<mnemonic>(<args>)"
def p_inst_1(self, t):
'inst : ID DBLCOLON ID LPAREN arg_list RPAREN'
try:
format = self.formatMap[t[1]]
except KeyError:
error(t, 'instruction format "%s" not defined.' % t[1])
codeObj = format.defineInst(self, t[3], t[5], t.lexer.lineno)
comment = '\n// %s::%s(%s)\n' % (t[1], t[3], t[5])
codeObj.prepend_all(comment)
t[0] = codeObj
# The arg list generates a tuple, where the first element is a
# list of the positional args and the second element is a dict
# containing the keyword args.
def p_arg_list_0(self, t):
'arg_list : positional_arg_list COMMA keyword_arg_list'
t[0] = ( t[1], t[3] )
def p_arg_list_1(self, t):
'arg_list : positional_arg_list'
t[0] = ( t[1], {} )
def p_arg_list_2(self, t):
'arg_list : keyword_arg_list'
t[0] = ( [], t[1] )
def p_positional_arg_list_0(self, t):
'positional_arg_list : empty'
t[0] = []
def p_positional_arg_list_1(self, t):
'positional_arg_list : expr'
t[0] = [t[1]]
def p_positional_arg_list_2(self, t):
'positional_arg_list : positional_arg_list COMMA expr'
t[0] = t[1] + [t[3]]
def p_keyword_arg_list_0(self, t):
'keyword_arg_list : keyword_arg'
t[0] = t[1]
def p_keyword_arg_list_1(self, t):
'keyword_arg_list : keyword_arg_list COMMA keyword_arg'
t[0] = t[1]
t[0].update(t[3])
def p_keyword_arg(self, t):
'keyword_arg : ID EQUALS expr'
t[0] = { t[1] : t[3] }
#
# Basic expressions. These constitute the argument values of
# "function calls" (i.e. instruction definitions in the decode
# block) and default values for formal parameters of format
# functions.
#
# Right now, these are either strings, integers, or (recursively)
# lists of exprs (using Python square-bracket list syntax). Note
# that bare identifiers are trated as string constants here (since
# there isn't really a variable namespace to refer to).
#
def p_expr_0(self, t):
'''expr : ID
| INTLIT
| STRLIT
| CODELIT'''
t[0] = t[1]
def p_expr_1(self, t):
'''expr : LBRACKET list_expr RBRACKET'''
t[0] = t[2]
def p_list_expr_0(self, t):
'list_expr : expr'
t[0] = [t[1]]
def p_list_expr_1(self, t):
'list_expr : list_expr COMMA expr'
t[0] = t[1] + [t[3]]
def p_list_expr_2(self, t):
'list_expr : empty'
t[0] = []
#
# Empty production... use in other rules for readability.
#
def p_empty(self, t):
'empty :'
pass
# Parse error handler. Note that the argument here is the
# offending *token*, not a grammar symbol (hence the need to use
# t.value)
def p_error(self, t):
if t:
error(t, "syntax error at '%s'" % t.value)
else:
error("unknown syntax error")
# END OF GRAMMAR RULES
def updateExportContext(self):
# create a continuation that allows us to grab the current parser
def wrapInstObjParams(*args):
return InstObjParams(self, *args)
self.exportContext['InstObjParams'] = wrapInstObjParams
self.exportContext.update(self.templateMap)
def defFormat(self, id, params, code, lineno):
'''Define a new format'''
# make sure we haven't already defined this one
if id in self.formatMap:
error(lineno, 'format %s redefined.' % id)
# create new object and store in global map
self.formatMap[id] = Format(id, params, code)
def expandCpuSymbolsToDict(self, template):
'''Expand template with CPU-specific references into a
dictionary with an entry for each CPU model name. The entry
key is the model name and the corresponding value is the
template with the CPU-specific refs substituted for that
model.'''
# Protect '%'s that don't go with CPU-specific terms
t = re.sub(r'%(?!\(CPU_)', '%%', template)
result = {}
for cpu in self.cpuModels:
result[cpu.name] = t % cpu.strings
return result
def expandCpuSymbolsToString(self, template):
'''*If* the template has CPU-specific references, return a
single string containing a copy of the template for each CPU
model with the corresponding values substituted in. If the
template has no CPU-specific references, it is returned
unmodified.'''
if template.find('%(CPU_') != -1:
return reduce(lambda x,y: x+y,
self.expandCpuSymbolsToDict(template).values())
else:
return template
def protectCpuSymbols(self, template):
'''Protect CPU-specific references by doubling the
corresponding '%'s (in preparation for substituting a different
set of references into the template).'''
return re.sub(r'%(?=\(CPU_)', '%%', template)
def protectNonSubstPercents(self, s):
'''Protect any non-dict-substitution '%'s in a format string
(i.e. those not followed by '(')'''
return re.sub(r'%(?!\()', '%%', s)
def buildOperandTypeMap(self, user_dict, lineno):
"""Generate operandTypeMap from the user's 'def operand_types'
statement."""
operand_type = {}
for (ext, (desc, size)) in user_dict.iteritems():
if desc == 'signed int':
ctype = 'int%d_t' % size
is_signed = 1
elif desc == 'unsigned int':
ctype = 'uint%d_t' % size
is_signed = 0
elif desc == 'float':
is_signed = 1 # shouldn't really matter
if size == 32:
ctype = 'float'
elif size == 64:
ctype = 'double'
elif desc == 'twin64 int':
is_signed = 0
ctype = 'Twin64_t'
elif desc == 'twin32 int':
is_signed = 0
ctype = 'Twin32_t'
if ctype == '':
error(parser, lineno,
'Unrecognized type description "%s" in user_dict')
operand_type[ext] = (size, ctype, is_signed)
self.operandTypeMap = operand_type
def buildOperandNameMap(self, user_dict, lineno):
operand_name = {}
for op_name, val in user_dict.iteritems():
base_cls_name, dflt_ext, reg_spec, flags, sort_pri = val[:5]
if len(val) > 5:
read_code = val[5]
else:
read_code = None
if len(val) > 6:
write_code = val[6]
else:
write_code = None
if len(val) > 7:
error(lineno,
'error: too many attributes for operand "%s"' %
base_cls_name)
(dflt_size, dflt_ctype, dflt_is_signed) = \
self.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',
'read_code', 'write_code'):
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.
operand_name[op_name] = type(cls_name, (base_cls,), tmp_dict)
self.operandNameMap = operand_name
# Define operand variables.
operands = user_dict.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, '|'))
self.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, '|'))
self.operandsWithExtRE = \
re.compile(operandsWithExtREString, re.MULTILINE)
def substMungedOpNames(self, code):
'''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.)'''
return self.operandsWithExtRE.sub(r'\1', code)
def mungeSnippet(self, s):
'''Fix up code snippets for final substitution in templates.'''
if isinstance(s, str):
return self.substMungedOpNames(substBitOps(s))
else:
return s
def update_if_needed(self, file, contents):
'''Update the output file only if the new contents are
different from the current contents. Minimizes the files that
need to be rebuilt after minor changes.'''
file = os.path.join(self.output_dir, file)
update = False
if os.access(file, os.R_OK):
f = open(file, 'r')
old_contents = f.read()
f.close()
if contents != old_contents:
print 'Updating', file
os.remove(file) # in case it's write-protected
update = True
else:
print 'File', file, 'is unchanged'
else:
print 'Generating', file
update = True
if update:
f = open(file, 'w')
f.write(contents)
f.close()
# This regular expression matches '##include' directives
includeRE = re.compile(r'^\s*##include\s+"(?P<filename>[\w/.-]*)".*$',
re.MULTILINE)
def replace_include(self, matchobj, dirname):
"""Function to replace a matched '##include' directive with the
contents of the specified file (with nested ##includes
replaced recursively). 'matchobj' is an re match object
(from a match of includeRE) and 'dirname' is the directory
relative to which the file path should be resolved."""
fname = matchobj.group('filename')
full_fname = os.path.normpath(os.path.join(dirname, fname))
contents = '##newfile "%s"\n%s\n##endfile\n' % \
(full_fname, self.read_and_flatten(full_fname))
return contents
def read_and_flatten(self, filename):
"""Read a file and recursively flatten nested '##include' files."""
current_dir = os.path.dirname(filename)
try:
contents = open(filename).read()
except IOError:
error('Error including file "%s"' % filename)
self.fileNameStack.push((filename, 0))
# Find any includes and include them
def replace(matchobj):
return self.replace_include(matchobj, current_dir)
contents = self.includeRE.sub(replace, contents)
self.fileNameStack.pop()
return contents
def _parse_isa_desc(self, isa_desc_file):
'''Read in and parse the ISA description.'''
# Read file and (recursively) all included files into a string.
# PLY requires that the input be in a single string so we have to
# do this up front.
isa_desc = self.read_and_flatten(isa_desc_file)
# Initialize filename stack with outer file.
self.fileNameStack.push((isa_desc_file, 0))
# Parse it.
(isa_name, namespace, global_code, namespace_code) = \
self.parse(isa_desc)
# grab the last three path components of isa_desc_file to put in
# the output
filename = '/'.join(isa_desc_file.split('/')[-3:])
# generate decoder.hh
includes = '#include "base/bitfield.hh" // for bitfield support'
global_output = global_code.header_output
namespace_output = namespace_code.header_output
decode_function = ''
self.update_if_needed('decoder.hh', file_template % vars())
# generate decoder.cc
includes = '#include "decoder.hh"'
global_output = global_code.decoder_output
namespace_output = namespace_code.decoder_output
# namespace_output += namespace_code.decode_block
decode_function = namespace_code.decode_block
self.update_if_needed('decoder.cc', file_template % vars())
# generate per-cpu exec files
for cpu in self.cpuModels:
includes = '#include "decoder.hh"\n'
includes += cpu.includes
global_output = global_code.exec_output[cpu.name]
namespace_output = namespace_code.exec_output[cpu.name]
decode_function = ''
self.update_if_needed(cpu.filename, file_template % vars())
# The variable names here are hacky, but this will creat local
# variables which will be referenced in vars() which have the
# value of the globals.
MaxInstSrcRegs = self.maxInstSrcRegs
MaxInstDestRegs = self.maxInstDestRegs
# max_inst_regs.hh
self.update_if_needed('max_inst_regs.hh',
max_inst_regs_template % vars())
def parse_isa_desc(self, *args, **kwargs):
try:
self._parse_isa_desc(*args, **kwargs)
except ISAParserError, e:
e.exit(self.fileNameStack)
# Called as script: get args from command line.
# Args are: <path to cpu_models.py> <isa desc file> <output dir> <cpu models>
if __name__ == '__main__':
execfile(sys.argv[1]) # read in CpuModel definitions
cpu_models = [CpuModel.dict[cpu] for cpu in sys.argv[4:]]
ISAParser(sys.argv[3], cpu_models).parse_isa_desc(sys.argv[2])