#! /usr/bin/env python
# $Id$
# Copyright (c) 2003 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.
import os
import sys
import re
import string
# get type names
from types import *
# Check arguments. Right now there are only two: the name of the ISA
# description (input) file and the name of the C++ decoder (output) file.
isa_desc_filename = sys.argv[1]
decoder_filename = sys.argv[2]
# Might as well suck the file in while we're here. This way if it's a
# bad filename we don't waste a lot of time building the parser :-).
input = open(isa_desc_filename)
isa_desc = input.read()
input.close()
# Prepend the directory where the PLY lex & yacc modules are found
# to the search path. Assumes we're compiling in a subdirectory
# of 'build' in the current tree.
sys.path[0:0] = [os.environ['M5_EXT'] + '/ply']
import lex
import yacc
#####################################################################
#
# 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', 'DECLARE', 'DECODE', 'DEFAULT', 'DEF', 'FORMAT',
'LET', 'NAMESPACE', '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',
# not used any more... commented out to suppress PLY warning
# 'LBRACKET', 'RBRACKET',
'LBRACE', 'RBRACE',
'LESS', 'GREATER',
'COMMA', 'SEMI', 'COLON', 'DBLCOLON',
'ASTERISK',
# C preprocessor directives
'CPPDIRECTIVE'
)
# Regular expressions for token matching
t_LPAREN = r'\('
t_RPAREN = r'\)'
# not used any more... commented out to suppress PLY warning
# t_LBRACKET = r'\['
# t_RBRACKET = r'\]'
t_LBRACE = r'\{'
t_RBRACE = r'\}'
t_LESS = r'\<'
t_GREATER = r'\>'
t_COMMA = r','
t_SEMI = 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(t):
r'[A-Za-z_]\w*'
t.type = reserved_map.get(t.value,'ID')
return t
# Integer literal
def t_INTLIT(t):
r'(0x[\da-fA-F]+)|\d+'
try:
t.value = int(t.value,0)
except ValueError:
error(t.lineno, '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(t):
r"(?m)'([^'])+'"
# strip off quotes
t.value = t.value[1:-1]
t.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(t):
r"(?m)\{\{([^\}]|}(?!\}))+\}\}"
# strip off {{ & }}
t.value = t.value[2:-2]
t.lineno += t.value.count('\n')
return t
def t_CPPDIRECTIVE(t):
r'^\#.*\n'
t.lineno += t.value.count('\n')
return t
#
# The functions t_NEWLINE, t_ignore, and t_error are
# special for the lex module.
#
# Newlines
def t_NEWLINE(t):
r'\n+'
t.lineno += t.value.count('\n')
# Comments
def t_comment(t):
r'//.*'
# Completely ignored characters
t_ignore = ' \t\x0c'
# Error handler
def t_error(t):
error(t.lineno, "illegal character '%s'" % t.value[0])
t.skip(1)
# Build the lexer
lex.lex()
#####################################################################
#
# 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]).
#####################################################################
# Not sure why, but we get a handful of shift/reduce conflicts on DECLARE.
# By default these get resolved as shifts, which is correct, but
# warnings are printed. Explicitly marking DECLARE as right-associative
# suppresses the warnings.
precedence = (
('right', 'DECLARE'),
)
# 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(t):
'specification : opt_defs_and_declares name_decl opt_defs_and_declares decode_block'
global_decls1 = t[1]
isa_name = t[2]
namespace = isa_name + "Inst"
global_decls2 = t[3]
(inst_decls, code) = t[4]
code = indent(code)
# grab the last three path components of isa_desc_filename
filename = '/'.join(isa_desc_filename.split('/')[-3:])
# if the isa_desc file defines a 'rcs_id' string,
# echo that into the output too
try:
local_rcs_id = rcs_id
# strip $s out of ID so it doesn't get re-substituted
local_rcs_id = re.sub(r'\$', '', local_rcs_id)
except NameError:
local_rcs_id = 'Id: no RCS id found'
output = open(decoder_filename, 'w')
# split string to keep rcs from substituting this file's RCS id in
print >> output, '/* $Id' + '''$ */
/*
* Copyright (c) 2003
* The Regents of The University of Michigan
* All Rights Reserved
*
* This code is part of the M5 simulator, developed by Nathan Binkert,
* Erik Hallnor, Steve Raasch, and Steve Reinhardt, with contributions
* from Ron Dreslinski, Dave Greene, and Lisa Hsu.
*
* Permission is granted to use, copy, create derivative works and
* redistribute this software and such derivative works for any
* purpose, so long as the copyright notice above, this grant of
* permission, and the disclaimer below appear in all copies made; and
* so long as the name of The University of Michigan is not used in
* any advertising or publicity pertaining to the use or distribution
* of this software without specific, written prior authorization.
*
* THIS SOFTWARE IS PROVIDED AS IS, WITHOUT REPRESENTATION FROM THE
* UNIVERSITY OF MICHIGAN AS TO ITS FITNESS FOR ANY PURPOSE, AND
* WITHOUT WARRANTY BY THE UNIVERSITY OF MICHIGAN OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE. THE REGENTS OF THE UNIVERSITY OF MICHIGAN SHALL NOT BE
* LIABLE FOR ANY DAMAGES, INCLUDING DIRECT, SPECIAL, INDIRECT,
* INCIDENTAL, OR CONSEQUENTIAL DAMAGES, WITH RESPECT TO ANY CLAIM
* ARISING OUT OF OR IN CONNECTION WITH THE USE OF THE SOFTWARE, EVEN
* IF IT HAS BEEN OR IS HEREAFTER ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGES.
*/
/*
* DO NOT EDIT THIS FILE!!!
*
* It was automatically generated from this ISA description:
* Filename: %(filename)s
* RCS %(local_rcs_id)s
*/
#include "base/bitfield.hh" // required for bitfield support
/////////////////////////////////////
// Global defs (outside namespace) //
/////////////////////////////////////
%(global_decls1)s
/**
* Namespace for %(isa_name)s static instruction objects.
*/
namespace %(namespace)s
{
/////////////////////////////////////
// Global defs (within namespace) //
/////////////////////////////////////
%(global_decls2)s
////////////////////////////////////
// Declares from inst definitions //
////////////////////////////////////
%(inst_decls)s
} // namespace %(namespace)s
//////////////////////
// Decoder function //
//////////////////////
StaticInstPtr<%(isa_name)s>
%(isa_name)s::decodeInst(%(isa_name)s::MachInst machInst)
{
using namespace %(namespace)s;
%(code)s
} // decodeInst
''' % vars()
output.close()
# ISA name declaration looks like "namespace <foo>;"
def p_name_decl(t):
'name_decl : NAMESPACE ID SEMI'
t[0] = t[2]
# 'opt_defs_and_declares' is a possibly empty sequence of
# defs and/or declares.
def p_opt_defs_and_declares_0(t):
'opt_defs_and_declares : empty'
t[0] = ''
def p_opt_defs_and_declares_1(t):
'opt_defs_and_declares : defs_and_declares'
t[0] = t[1]
def p_defs_and_declares_0(t):
'defs_and_declares : def_or_declare'
t[0] = t[1]
def p_defs_and_declares_1(t):
'defs_and_declares : defs_and_declares def_or_declare'
t[0] = t[1] + t[2]
# The list of possible definition/declaration statements.
def p_def_or_declare(t):
'''def_or_declare : def_format
| def_bitfield
| def_template
| global_declare
| global_let
| cpp_directive'''
t[0] = t[1]
# preprocessor directives are copied directly to the output.
def p_cpp_directive(t):
'''cpp_directive : CPPDIRECTIVE'''
t[0] = t[1]
# Global declares 'declare {{...}}' (C++ code blocks) are copied
# directly to the output.
def p_global_declare(t):
'global_declare : DECLARE CODELIT SEMI'
t[0] = substBitOps(t[2])
# global let blocks 'let {{...}}' (Python code blocks) are executed
# directly when seen. These are typically used to initialize global
# Python variables used in later format definitions.
def p_global_let(t):
'global_let : LET CODELIT SEMI'
try:
exec(fixPythonIndentation(t[2]))
except:
error_bt(t.lineno(1), 'error in global let block "%s".' % t[2])
t[0] = '' # 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(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)
t[0] = '#undef %s\n#define %s\t%s\n' % (t[4], t[4], expr)
# alternate form for single bit: 'def [signed] bitfield <ID> [<bit>]'
def p_def_bitfield_1(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)
t[0] = '#undef %s\n#define %s\t%s\n' % (t[4], t[4], expr)
def p_opt_signed_0(t):
'opt_signed : SIGNED'
t[0] = t[1]
def p_opt_signed_1(t):
'opt_signed : empty'
t[0] = ''
# Global map variable to hold templates
templateMap = {}
def p_def_template(t):
'def_template : DEF TEMPLATE ID CODELIT SEMI'
templateMap[t[3]] = t[4]
t[0] = ''
# An instruction format definition looks like
# "def format <fmt>(<params>) {{...}};"
def p_def_format(t):
'def_format : DEF FORMAT ID LPAREN param_list RPAREN CODELIT SEMI'
(id, params, code) = (t[3], t[5], t[7])
defFormat(id, params, code, t.lineno(1))
# insert a comment into the output to note that the def was processed
t[0] = '''
//
// parser: format %s defined
//
''' % id
# The formal parameter list for an instruction format is a possibly
# empty list of comma-separated parameters.
def p_param_list_0(t):
'param_list : empty'
t[0] = [ ]
def p_param_list_1(t):
'param_list : param'
t[0] = [t[1]]
def p_param_list_2(t):
'param_list : param_list COMMA param'
t[0] = t[1]
t[0].append(t[3])
# Each formal parameter is either an identifier or an identifier
# preceded by an asterisk. As in Python, the latter (if present) gets
# a tuple containing all the excess positional arguments, allowing
# varargs functions.
def p_param_0(t):
'param : ID'
t[0] = t[1]
def p_param_1(t):
'param : ASTERISK ID'
# just concatenate them: '*ID'
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(t):
'decode_block : DECODE ID opt_default LBRACE decode_stmt_list RBRACE'
default_defaults = defaultStack.pop()
(decls, code, has_default) = t[5]
# use the "default defaults" only if there was no explicit
# default statement in decode_stmt_list
if not has_default:
(default_decls, default_code) = default_defaults
decls += default_decls
code += default_code
t[0] = (decls, '''
switch (%s) {
%s
}
''' % (t[2], indent(code)))
# 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(t):
'opt_default : empty'
# no default specified: reuse the one currently at the top of the stack
defaultStack.push(defaultStack.top())
# no meaningful value returned
t[0] = None
def p_opt_default_1(t):
'opt_default : DEFAULT inst'
# push the new default
(decls, code) = t[2]
defaultStack.push((decls, '\ndefault:\n%sbreak;' % code))
# no meaningful value returned
t[0] = None
def p_decode_stmt_list_0(t):
'decode_stmt_list : decode_stmt'
t[0] = t[1]
def p_decode_stmt_list_1(t):
'decode_stmt_list : decode_stmt decode_stmt_list'
(decls1, code1, has_default1) = t[1]
(decls2, code2, has_default2) = t[2]
if (has_default1 and has_default2):
error(t.lineno(1), 'Two default cases in decode block')
t[0] = (decls1 + '\n' + decls2, code1 + '\n' + code2,
has_default1 or has_default2)
#
# 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 both the declaration and decode
# 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(t):
'decode_stmt : CPPDIRECTIVE'
t[0] = (t[1], t[1], 0)
# 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(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.
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(t):
'push_format_id : ID'
try:
formatStack.push(formatMap[t[1]])
t[0] = ('', '// format %s' % t[1])
except KeyError:
error(t.lineno(1), '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(t):
'decode_stmt : case_label COLON decode_block'
(label, is_default) = t[1]
(decls, code) = t[3]
# just wrap the decoding code from the block as a case in the
# outer switch statement.
t[0] = (decls, '\n%s:\n%s' % (label, indent(code)), is_default)
# Instruction definition (finally!).
def p_decode_stmt_inst(t):
'decode_stmt : case_label COLON inst SEMI'
(label, is_default) = t[1]
(decls, code) = t[3]
t[0] = (decls, '\n%s:%sbreak;' % (label, indent(code)), is_default)
# The case label is either a list of one or more constants or 'default'
def p_case_label_0(t):
'case_label : intlit_list'
t[0] = (': '.join(map(lambda a: 'case %#x' % a, t[1])), 0)
def p_case_label_1(t):
'case_label : DEFAULT'
t[0] = ('default', 1)
#
# 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(t):
'intlit_list : INTLIT'
t[0] = [t[1]]
def p_intlit_list_1(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(t):
'inst : ID LPAREN arg_list RPAREN'
# Pass the ID and arg list to the current format class to deal with.
currentFormat = formatStack.top()
(decls, code) = currentFormat.defineInst(t[1], t[3], t.lineno(1))
args = ','.join(map(str, t[3]))
args = re.sub('(?m)^', '//', args)
args = re.sub('^//', '', args)
comment = '// %s::%s(%s)\n' % (currentFormat.id, t[1], args)
t[0] = (comment + decls, comment + code)
# Define an instruction using an explicitly specified format:
# "<fmt>::<mnemonic>(<args>)"
def p_inst_1(t):
'inst : ID DBLCOLON ID LPAREN arg_list RPAREN'
try:
format = formatMap[t[1]]
except KeyError:
error(t.lineno(1), 'instruction format "%s" not defined.' % t[1])
(decls, code) = format.defineInst(t[3], t[5], t.lineno(1))
comment = '// %s::%s(%s)\n' % (t[1], t[3], t[5])
t[0] = (comment + decls, comment + code)
def p_arg_list_0(t):
'arg_list : empty'
t[0] = [ ]
def p_arg_list_1(t):
'arg_list : arg'
t[0] = [t[1]]
def p_arg_list_2(t):
'arg_list : arg_list COMMA arg'
t[0] = t[1]
t[0].append(t[3])
def p_arg(t):
'''arg : ID
| INTLIT
| STRLIT
| CODELIT'''
t[0] = t[1]
#
# Empty production... use in other rules for readability.
#
def p_empty(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(t):
if t:
error(t.lineno, "syntax error at '%s'" % t.value)
else:
error_bt(0, "unknown syntax error")
# END OF GRAMMAR RULES
#
# Now build the parser.
yacc.yacc()
################
# 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:
def __init__(self, id, params, code):
# constructor: just save away arguments
self.id = id
self.params = params
# strip blank lines from code (ones at the end are troublesome)
code = re.sub(r'(?m)^\s*$', '', code);
if code == '':
code = ' pass\n'
param_list = string.join(params, ", ")
f = 'def defInst(name, Name, ' + param_list + '):\n' + code
exec(f)
self.func = defInst
def defineInst(self, name, args, lineno):
# automatically provide a capitalized version of mnemonic
Name = string.capitalize(name)
try:
retval = self.func(name, Name, *args)
except:
error_bt(lineno, 'error defining "%s".' % name)
return retval
# Special null format to catch an implicit-format instruction
# definition outside of any format block.
class NoFormat:
def __init__(self):
self.defaultInst = ''
def defineInst(self, name, args, lineno):
error(lineno,
'instruction definition "%s" with no active format!' % name)
# This dictionary maps format name strings to Format objects.
formatMap = {}
# Define a new format
def defFormat(id, params, code, lineno):
# make sure we haven't already defined this one
if formatMap.get(id, None) != None:
error(lineno, 'format %s redefined.' % id)
# create new object and store in global map
formatMap[id] = Format(id, params, code)
##############
# Stack: a simple stack object. Used for both formats (formatStack)
# and default cases (defaultStack).
class Stack:
def __init__(self, initItem):
self.stack = [ initItem ]
def push(self, item):
self.stack.append(item);
def pop(self):
return self.stack.pop()
def top(self):
return self.stack[-1]
# The global format stack.
formatStack = Stack(NoFormat())
# The global default case stack.
defaultStack = Stack( None )
###################
# 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
# Error handler. Just call exit. Output formatted to work under
# Emacs compile-mode.
def error(lineno, string):
sys.exit("%s:%d: %s" % (isa_desc_filename, lineno, string))
# Like error(), but include a Python stack backtrace (for processing
# Python exceptions).
def error_bt(lineno, string):
print >> sys.stderr, "%s:%d: %s" % (isa_desc_filename, lineno, string)
raise
#####################################################################
#
# 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
def makeList(list_or_item):
if not list_or_item:
return []
elif type(list_or_item) == ListType:
return list_or_item
else:
return [ list_or_item ]
# generate operandSizeMap based on provided operandTypeMap:
# basically generate equiv. C++ type and make is_signed flag
def buildOperandSizeMap():
global operandSizeMap
operandSizeMap = {}
for ext in operandTypeMap.keys():
(desc, size) = operandTypeMap[ext]
if desc == 'signed int':
type = 'int%d_t' % size
is_signed = 1
elif desc == 'unsigned int':
type = 'uint%d_t' % size
is_signed = 0
elif desc == 'float':
is_signed = 1 # shouldn't really matter
if size == 32:
type = 'float'
elif size == 64:
type = 'double'
if type == '':
error(0, 'Unrecognized type description "%s" in operandTypeMap')
operandSizeMap[ext] = (size, type, is_signed)
#
# Base class for operand traits. An instance of this class (or actually
# a class derived from this one) encapsulates the traits of a particular
# operand type (e.g., "32-bit integer register").
#
class OperandTraits:
def __init__(self, dflt_ext, reg_spec, flags, sort_pri):
# Force construction of operandSizeMap from operandTypeMap
# if it hasn't happened yet
if not globals().has_key('operandSizeMap'):
buildOperandSizeMap()
self.dflt_ext = dflt_ext
(self.dflt_size, self.dflt_type, self.dflt_is_signed) = \
operandSizeMap[dflt_ext]
self.reg_spec = reg_spec
# 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')
self.flags = ( [], [], [] )
elif type(flags) == StringType:
# a single flag: assumed to be unconditional
self.flags = ( [ flags ], [], [] )
elif type(flags) == ListType:
# a list of flags: also assumed to be unconditional
self.flags = ( flags, [], [] )
elif type(flags) == TupleType:
# 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
self.flags = (makeList(uncond_flags),
makeList(src_flags), makeList(dest_flags))
self.sort_pri = sort_pri
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, op_desc):
# note the empty slice '[:]' gives us a copy of self.flags[0]
# instead of a reference to it
my_flags = self.flags[0][:]
if op_desc.is_src:
my_flags += self.flags[1]
if op_desc.is_dest:
my_flags += self.flags[2]
return my_flags
def makeDecl(self, op_desc):
(size, type, is_signed) = operandSizeMap[op_desc.eff_ext]
# Note that initializations in the declarations are solely
# to avoid 'uninitialized variable' errors from the compiler.
return type + ' ' + op_desc.munged_name + ' = 0;\n';
class IntRegOperandTraits(OperandTraits):
def isReg(self):
return 1
def isIntReg(self):
return 1
def makeConstructor(self, op_desc):
c = ''
if op_desc.is_src:
c += '\n\t_srcRegIdx[%d] = %s;' % \
(op_desc.src_reg_idx, self.reg_spec)
if op_desc.is_dest:
c += '\n\t_destRegIdx[%d] = %s;' % \
(op_desc.dest_reg_idx, self.reg_spec)
return c
def makeRead(self, op_desc, cpu_model):
(size, type, is_signed) = operandSizeMap[op_desc.eff_ext]
if (type == 'float' or type == 'double'):
error(0, 'Attempt to read integer register as FP')
if (size == self.dflt_size):
return '%s = xc->readIntReg(_srcRegIdx[%d]);\n' % \
(op_desc.munged_name, op_desc.src_reg_idx)
else:
return '%s = bits(xc->readIntReg(_srcRegIdx[%d]), %d, 0);\n' % \
(op_desc.munged_name, op_desc.src_reg_idx, size-1)
def makeWrite(self, op_desc, cpu_model):
(size, type, is_signed) = operandSizeMap[op_desc.eff_ext]
if (type == 'float' or type == 'double'):
error(0, 'Attempt to write integer register as FP')
if (size != self.dflt_size and is_signed):
final_val = 'sext<%d>(%s)' % (size, op_desc.munged_name)
else:
final_val = op_desc.munged_name
wb = '''
{
%s final_val = %s;
xc->setIntReg(_destRegIdx[%d], final_val);\n
if (traceData) { traceData->setData(final_val); }
}''' % (self.dflt_type, final_val, op_desc.dest_reg_idx)
return wb
class FloatRegOperandTraits(OperandTraits):
def isReg(self):
return 1
def isFloatReg(self):
return 1
def makeConstructor(self, op_desc):
c = ''
if op_desc.is_src:
c += '\n\t_srcRegIdx[%d] = %s + FP_Base_DepTag;' % \
(op_desc.src_reg_idx, self.reg_spec)
if op_desc.is_dest:
c += '\n\t_destRegIdx[%d] = %s + FP_Base_DepTag;' % \
(op_desc.dest_reg_idx, self.reg_spec)
return c
def makeRead(self, op_desc, cpu_model):
(size, type, is_signed) = operandSizeMap[op_desc.eff_ext]
bit_select = 0
if (type == 'float'):
func = 'readFloatRegSingle'
elif (type == 'double'):
func = 'readFloatRegDouble'
else:
func = 'readFloatRegInt'
if (size != self.dflt_size):
bit_select = 1
base = 'xc->%s(_srcRegIdx[%d] - FP_Base_DepTag)' % \
(func, op_desc.src_reg_idx)
if bit_select:
return '%s = bits(%s, %d, 0);\n' % \
(op_desc.munged_name, base, size-1)
else:
return '%s = %s;\n' % (op_desc.munged_name, base)
def makeWrite(self, op_desc, cpu_model):
(size, type, is_signed) = operandSizeMap[op_desc.eff_ext]
final_val = op_desc.munged_name
if (type == 'float'):
func = 'setFloatRegSingle'
elif (type == 'double'):
func = 'setFloatRegDouble'
else:
func = 'setFloatRegInt'
type = 'uint%d_t' % self.dflt_size
if (size != self.dflt_size and is_signed):
final_val = 'sext<%d>(%s)' % (size, op_desc.munged_name)
wb = '''
{
%s final_val = %s;
xc->%s(_destRegIdx[%d] - FP_Base_DepTag, final_val);\n
if (traceData) { traceData->setData(final_val); }
}''' % (type, final_val, func, op_desc.dest_reg_idx)
return wb
class ControlRegOperandTraits(OperandTraits):
def isReg(self):
return 1
def isControlReg(self):
return 1
def makeConstructor(self, op_desc):
c = ''
if op_desc.is_src:
c += '\n\t_srcRegIdx[%d] = %s_DepTag;' % \
(op_desc.src_reg_idx, self.reg_spec)
if op_desc.is_dest:
c += '\n\t_destRegIdx[%d] = %s_DepTag;' % \
(op_desc.dest_reg_idx, self.reg_spec)
return c
def makeRead(self, op_desc, cpu_model):
(size, type, is_signed) = operandSizeMap[op_desc.eff_ext]
bit_select = 0
if (type == 'float' or type == 'double'):
error(0, 'Attempt to read control register as FP')
base = 'xc->read%s()' % self.reg_spec
if size == self.dflt_size:
return '%s = %s;\n' % (op_desc.munged_name, base)
else:
return '%s = bits(%s, %d, 0);\n' % \
(op_desc.munged_name, base, size-1)
def makeWrite(self, op_desc, cpu_model):
(size, type, is_signed) = operandSizeMap[op_desc.eff_ext]
if (type == 'float' or type == 'double'):
error(0, 'Attempt to write control register as FP')
wb = 'xc->set%s(%s);\n' % (self.reg_spec, op_desc.munged_name)
wb += 'if (traceData) { traceData->setData(%s); }' % \
op_desc.munged_name
return wb
class MemOperandTraits(OperandTraits):
def isMem(self):
return 1
def makeConstructor(self, op_desc):
return ''
def makeDecl(self, op_desc):
(size, type, is_signed) = operandSizeMap[op_desc.eff_ext]
# Note that initializations in the declarations are solely
# to avoid 'uninitialized variable' errors from the compiler.
# Declare memory data variable.
c = '%s %s = 0;\n' % (type, op_desc.munged_name)
# Declare var to hold memory access flags.
c += 'unsigned %s_flags = memAccessFlags;\n' % op_desc.base_name
# If this operand is a dest (i.e., it's a store operation),
# then we need to declare a variable for the write result code
# as well.
if op_desc.is_dest:
c += 'uint64_t %s_write_result = 0;\n' % op_desc.base_name
return c
def makeRead(self, op_desc, cpu_model):
(size, type, is_signed) = operandSizeMap[op_desc.eff_ext]
eff_type = 'uint%d_t' % size
return 'fault = memAccessObj->read(EA, (%s&)%s, %s_flags);\n' \
% (eff_type, op_desc.munged_name, op_desc.base_name)
def makeWrite(self, op_desc, cpu_model):
(size, type, is_signed) = operandSizeMap[op_desc.eff_ext]
eff_type = 'uint%d_t' % size
return 'fault = memAccessObj->write((%s&)%s, EA, %s_flags,' \
' &%s_write_result);\n' \
% (eff_type, op_desc.munged_name, op_desc.base_name,
op_desc.base_name)
class NPCOperandTraits(OperandTraits):
def makeConstructor(self, op_desc):
return ''
def makeRead(self, op_desc, cpu_model):
return '%s = xc->readPC() + 4;\n' % op_desc.munged_name
def makeWrite(self, op_desc, cpu_model):
return 'xc->setNextPC(%s);\n' % op_desc.munged_name
#
# Define operand variables that get derived from the basic declaration
# of ISA-specific operands in operandTraitsMap. This function must be
# called by the ISA description file explicitly after defining
# operandTraitsMap (in a 'let' block).
#
def defineDerivedOperandVars():
global operands
operands = operandTraitsMap.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)
#
# Operand descriptor class. An instance of this class represents
# a specific operand for a code block.
#
class OperandDescriptor:
def __init__(self, full_name, base_name, ext, is_src, is_dest):
self.full_name = full_name
self.base_name = base_name
self.ext = ext
self.is_src = is_src
self.is_dest = is_dest
self.traits = operandTraitsMap[base_name]
# The 'effective extension' (eff_ext) is either the actual
# extension, if one was explicitly provided, or the default.
# The 'munged name' replaces the '.' between the base and
# extension (if any) with a '_' to make a legal C++ variable name.
if ext:
self.eff_ext = ext
self.munged_name = base_name + '_' + ext
else:
self.eff_ext = self.traits.dflt_ext
self.munged_name = base_name
# 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.traits.getFlags(self)
self.constructor = self.traits.makeConstructor(self)
self.exec_decl = self.traits.makeDecl(self)
if self.is_src:
self.simple_rd = self.traits.makeRead(self, 'simple')
self.dtld_rd = self.traits.makeRead(self, 'dtld')
else:
self.simple_rd = ''
self.dtld_rd = ''
if self.is_dest:
self.simple_wb = self.traits.makeWrite(self, 'simple')
self.dtld_wb = self.traits.makeWrite(self, 'dtld')
else:
self.simple_wb = ''
self.dtld_wb = ''
class OperandDescriptorList:
def __init__(self):
self.items = []
self.bases = {}
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.traits.sort_pri - b.traits.sort_pri)
# 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)
#
# Find all the operands in the given code block. Returns an operand
# descriptor list (instance of class OperandDescriptorList).
#
def findOperands(code):
operands = OperandDescriptorList()
# delete comments so we don't accidentally 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 = operands.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 = OperandDescriptor(op_full, op_base, op_ext,
is_src, is_dest)
operands.append(op_desc)
# start next search after end of current match
next_pos = match.end()
operands.sort()
# enumerate source & dest register operands... used in building
# constructor later
srcRegs = 0
destRegs = 0
operands.numFPDestRegs = 0
operands.numIntDestRegs = 0
for op_desc in operands:
if op_desc.traits.isReg():
if op_desc.is_src:
op_desc.src_reg_idx = srcRegs
srcRegs += 1
if op_desc.is_dest:
op_desc.dest_reg_idx = destRegs
destRegs += 1
if op_desc.traits.isFloatReg():
operands.numFPDestRegs += 1
elif op_desc.traits.isIntReg():
operands.numIntDestRegs += 1
operands.numSrcRegs = srcRegs
operands.numDestRegs = destRegs
# now make a final pass to finalize op_desc fields that may depend
# on the register enumeration
for op_desc in operands:
op_desc.finalize()
return operands
# Munge operand names in code string to make legal C++ variable names.
# (Will match munged_name attribute of OperandDescriptor object.)
def substMungedOpNames(code):
return operandsWithExtRE.sub(r'\1_\2', code)
def joinLists(t):
return map(string.join, t)
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
class CodeBlock:
def __init__(self, code):
self.orig_code = code
self.operands = findOperands(code)
self.code = substMungedOpNames(substBitOps(code))
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.exec_decl = self.operands.concatAttrStrings('exec_decl')
is_mem = lambda op: op.traits.isMem()
not_mem = lambda op: not op.traits.isMem()
self.simple_rd = self.operands.concatAttrStrings('simple_rd')
self.simple_wb = self.operands.concatAttrStrings('simple_wb')
self.simple_mem_rd = \
self.operands.concatSomeAttrStrings(is_mem, 'simple_rd')
self.simple_mem_wb = \
self.operands.concatSomeAttrStrings(is_mem, 'simple_wb')
self.simple_nonmem_rd = \
self.operands.concatSomeAttrStrings(not_mem, 'simple_rd')
self.simple_nonmem_wb = \
self.operands.concatSomeAttrStrings(not_mem, 'simple_wb')
self.dtld_rd = self.operands.concatAttrStrings('dtld_rd')
self.dtld_wb = self.operands.concatAttrStrings('dtld_wb')
self.dtld_mem_rd = \
self.operands.concatSomeAttrStrings(is_mem, 'dtld_rd')
self.dtld_mem_wb = \
self.operands.concatSomeAttrStrings(is_mem, 'dtld_wb')
self.dtld_nonmem_rd = \
self.operands.concatSomeAttrStrings(not_mem, 'dtld_rd')
self.dtld_nonmem_wb = \
self.operands.concatSomeAttrStrings(not_mem, 'dtld_wb')
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 will be overridden
# later otherwise.
if 'IsStore' in self.flags:
self.op_class = 'WrPort'
elif 'IsLoad' in self.flags or 'IsPrefetch' in self.flags:
self.op_class = 'RdPort'
elif 'IsFloating' in self.flags:
self.op_class = 'FloatADD'
else:
self.op_class = 'IntALU'
# Assume all instruction flags are of the form 'IsFoo'
instFlagRE = re.compile(r'Is.*')
# OpClass constants are just a little more complicated
opClassRE = re.compile(r'Int.*|Float.*|.*Port|No_OpClass')
class InstObjParams:
def __init__(self, mnem, class_name, base_class = '',
code_block = None, opt_args = []):
self.mnemonic = mnem
self.class_name = class_name
self.base_class = base_class
if code_block:
for code_attr in code_block.__dict__.keys():
setattr(self, code_attr, getattr(code_block, code_attr))
else:
self.constructor = ''
self.flags = []
# 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, '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 = ''
def subst(self, *args):
result = []
for t in args:
if not templateMap.has_key(t):
error(0, 'InstObjParams::subst: undefined template "%s"' % t)
try:
result.append(templateMap[t] % self.__dict__)
except KeyError, key:
error(0, 'InstObjParams::subst: no definition for "%s"' % key)
if len(args) == 1:
result = result[0]
return result
#
# All set... read in and parse the ISA description.
#
yacc.parse(isa_desc)