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|
#! /usr/bin/env python
# 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.
import os
import sys
import re
import string
import traceback
# get type names
from types import *
# 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', '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',
# 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'
# 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'\('
t_RPAREN = r'\)'
# 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
def t_NEWFILE(t):
r'^\#\#newfile\s+"[\w/.-]*"'
global fileNameStack
fileNameStack.append((t.value[11:-1], t.lineno))
t.lineno = 0
def t_ENDFILE(t):
r'^\#\#endfile'
(filename, t.lineno) = fileNameStack.pop()
#
# 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]).
#####################################################################
# 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_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>
%(isa_name)s::decodeInst(%(isa_name)s::MachInst 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(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(t):
'opt_defs_and_outputs : empty'
t[0] = GenCode()
def p_opt_defs_and_outputs_1(t):
'opt_defs_and_outputs : defs_and_outputs'
t[0] = t[1]
def p_defs_and_outputs_0(t):
'defs_and_outputs : def_or_output'
t[0] = t[1]
def p_defs_and_outputs_1(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(t):
'''def_or_output : def_format
| def_bitfield
| 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.
# Protect any non-dict-substitution '%'s in a format string
# (i.e. those not followed by '(')
def protect_non_subst_percents(s):
return re.sub(r'%(?!\()', '%%', s)
# 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(s):
s = protect_non_subst_percents(s)
# protects cpu-specific symbols too
s = protect_cpu_symbols(s)
return substBitOps(s % templateMap)
def p_output_header(t):
'output_header : OUTPUT HEADER CODELIT SEMI'
t[0] = GenCode(header_output = process_output(t[3]))
def p_output_decoder(t):
'output_decoder : OUTPUT DECODER CODELIT SEMI'
t[0] = GenCode(decoder_output = process_output(t[3]))
def p_output_exec(t):
'output_exec : OUTPUT EXEC CODELIT SEMI'
t[0] = GenCode(exec_output = 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(t):
'global_let : LET CODELIT SEMI'
updateExportContext()
try:
exec fixPythonIndentation(t[2]) in exportContext
except Exception, exc:
error(t.lineno(1),
'error: %s in global let block "%s".' % (exc, t[2]))
t[0] = GenCode() # contributes nothing to the output C++ file
# Define the mapping from operand type extensions to C++ types and bit
# widths (stored in operandTypeMap).
def p_def_operand_types(t):
'def_operand_types : DEF OPERAND_TYPES CODELIT SEMI'
s = 'global operandTypeMap; operandTypeMap = {' + t[3] + '}'
try:
exec s
except Exception, exc:
error(t.lineno(1),
'error: %s in def operand_types block "%s".' % (exc, t[3]))
t[0] = GenCode() # contributes nothing to the output C++ file
# Define the mapping from operand names to operand classes and other
# traits. Stored in operandTraitsMap.
def p_def_operands(t):
'def_operands : DEF OPERANDS CODELIT SEMI'
s = 'global operandTraitsMap; operandTraitsMap = {' + t[3] + '}'
try:
exec s
except Exception, exc:
error(t.lineno(1),
'error: %s in def operands block "%s".' % (exc, t[3]))
defineDerivedOperandVars()
t[0] = GenCode() # 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)
hash_define = '#undef %s\n#define %s\t%s\n' % (t[4], t[4], expr)
t[0] = GenCode(header_output = hash_define)
# 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)
hash_define = '#undef %s\n#define %s\t%s\n' % (t[4], t[4], expr)
t[0] = GenCode(header_output = hash_define)
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]] = Template(t[4])
t[0] = GenCode()
# 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))
t[0] = GenCode()
# 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()
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(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
codeObj = t[2]
codeObj.wrap_decode_block('\ndefault:\n', 'break;\n')
defaultStack.push(codeObj)
# 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'
if (t[1].has_decode_default and t[2].has_decode_default):
error(t.lineno(1), '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(t):
'decode_stmt : CPPDIRECTIVE'
t[0] = GenCode(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(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 = 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(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(t):
'case_label : intlit_list'
t[0] = ': '.join(map(lambda a: 'case %#x' % a, t[1]))
def p_case_label_1(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(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()
codeObj = 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 = '\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(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])
codeObj = format.defineInst(t[3], t[5], t.lineno(1))
comment = '\n// %s::%s(%s)\n' % (t[1], t[3], t[5])
codeObj.prepend_all(comment)
t[0] = codeObj
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()
#####################################################################
#
# Support Classes
#
#####################################################################
################
# CpuModel class
#
# The CpuModel class encapsulates everything we need to know about a
# particular CPU model.
class CpuModel:
# List of all CPU models. Accessible as CpuModel.list.
list = []
# Constructor. Automatically adds models to CpuModel.list.
def __init__(self, name, filename, includes, strings):
self.name = name
self.filename = filename # filename for output exec code
self.includes = includes # include files needed in exec file
# The 'strings' dict holds all the per-CPU symbols we can
# substitute into templates etc.
self.strings = strings
# Add self to list.
CpuModel.list.append(self)
# Define CPU models. The following lines should contain the only
# CPU-model-specific information in this file. Note that the ISA
# description itself should have *no* CPU-model-specific content.
CpuModel('SimpleCPU', 'simple_cpu_exec.cc',
'#include "cpu/simple/cpu.hh"',
{ 'CPU_exec_context': 'SimpleCPU' })
CpuModel('FastCPU', 'fast_cpu_exec.cc',
'#include "cpu/fast/cpu.hh"',
{ 'CPU_exec_context': 'FastCPU' })
CpuModel('FullCPU', 'full_cpu_exec.cc',
'#include "encumbered/cpu/full/dyn_inst.hh"',
{ 'CPU_exec_context': 'DynInst' })
CpuModel('AlphaFullCPU', 'alpha_o3_exec.cc',
'#include "cpu/o3/alpha_dyn_inst.hh"',
{ 'CPU_exec_context': 'AlphaDynInst<AlphaSimpleImpl>' })
# 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.
def expand_cpu_symbols_to_dict(template):
# Protect '%'s that don't go with CPU-specific terms
t = re.sub(r'%(?!\(CPU_)', '%%', template)
result = {}
for cpu in CpuModel.list:
result[cpu.name] = t % cpu.strings
return result
# *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.
def expand_cpu_symbols_to_string(template):
if template.find('%(CPU_') != -1:
return reduce(lambda x,y: x+y,
expand_cpu_symbols_to_dict(template).values())
else:
return template
# Protect CPU-specific references by doubling the corresponding '%'s
# (in preparation for substituting a different set of references into
# the template).
def protect_cpu_symbols(template):
return re.sub(r'%(?=\(CPU_)', '%%', template)
###############
# 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:
# 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,
header_output = '', decoder_output = '', exec_output = '',
decode_block = '', has_decode_default = False):
self.header_output = expand_cpu_symbols_to_string(header_output)
self.decoder_output = expand_cpu_symbols_to_string(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 = expand_cpu_symbols_to_dict(exec_output)
self.decode_block = expand_cpu_symbols_to_string(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 CpuModel.list:
n = cpu.name
exec_output[n] = self.exec_output[n] + other.exec_output[n]
return GenCode(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 CpuModel.list:
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
################
# 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
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, name, args, lineno):
context = {}
updateExportContext()
context.update(exportContext)
context.update({ 'name': name, 'Name': string.capitalize(name) })
try:
vars = self.func(self.user_code, context, *args)
except Exception, exc:
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(**vars)
# 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). 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]
# 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. This function should be called when errors due
# to user input are detected (as opposed to parser bugs).
def error(lineno, string):
spaces = ""
for (filename, line) in fileNameStack[0:-1]:
print spaces + "In file included from " + filename
spaces += " "
# Uncomment the following line to get a Python stack backtrace for
# these errors too. Can be handy when trying to debug the parser.
# traceback.print_exc()
sys.exit(spaces + "%s:%d: %s" % (fileNameStack[-1][0], lineno, string))
# Like error(), but include a Python stack backtrace (for processing
# Python exceptions). This function should be called for errors that
# appear to be bugs in the parser itself.
def error_bt(lineno, string):
traceback.print_exc()
print >> sys.stderr, "%s:%d: %s" % (input_filename, lineno, string)
sys.exit(1)
#####################################################################
#
# 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
####################
# Template objects.
#
# Template objects are format strings that allow substitution from
# the attribute spaces of other objects (e.g. InstObjParams instances).
class Template:
def __init__(self, t):
self.template = t
def subst(self, d):
# Start with the template namespace. Make a copy since we're
# going to modify it.
myDict = templateMap.copy()
# if the argument is a dictionary, we just use it.
if isinstance(d, dict):
myDict.update(d)
# if the argument is an object, we use its attribute map.
elif hasattr(d, '__dict__'):
myDict.update(d.__dict__)
else:
raise TypeError, "Template.subst() arg must be or have dictionary"
# Protect non-Python-dict substitutions (e.g. if there's a printf
# in the templated C++ code)
template = protect_non_subst_percents(self.template)
# CPU-model-specific substitutions are handled later (in GenCode).
template = protect_cpu_symbols(template)
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 expand_cpu_symbols_to_string(self.template)
#####################################################################
#
# 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.base_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):
(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(this, %d);\n' % \
(op_desc.base_name, op_desc.src_reg_idx)
else:
return '%s = bits(xc->readIntReg(this, %d), %d, 0);\n' % \
(op_desc.base_name, op_desc.src_reg_idx, size-1)
def makeWrite(self, op_desc):
(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.base_name)
else:
final_val = op_desc.base_name
wb = '''
{
%s final_val = %s;
xc->setIntReg(this, %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):
(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(this, %d)' % \
(func, op_desc.src_reg_idx)
if bit_select:
return '%s = bits(%s, %d, 0);\n' % \
(op_desc.base_name, base, size-1)
else:
return '%s = %s;\n' % (op_desc.base_name, base)
def makeWrite(self, op_desc):
(size, type, is_signed) = operandSizeMap[op_desc.eff_ext]
final_val = op_desc.base_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.base_name)
wb = '''
{
%s final_val = %s;
xc->%s(this, %d, 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):
(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.base_name, base)
else:
return '%s = bits(%s, %d, 0);\n' % \
(op_desc.base_name, base, size-1)
def makeWrite(self, op_desc):
(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.base_name)
wb += 'if (traceData) { traceData->setData(%s); }' % \
op_desc.base_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.base_name)
return c
def makeRead(self, op_desc):
return ''
def makeWrite(self, op_desc):
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, op_desc):
(size, type, is_signed) = operandSizeMap[op_desc.eff_ext]
return size
class NPCOperandTraits(OperandTraits):
def makeConstructor(self, op_desc):
return ''
def makeRead(self, op_desc):
return '%s = xc->readPC() + 4;\n' % op_desc.base_name
def makeWrite(self, op_desc):
return 'xc->setNextPC(%s);\n' % op_desc.base_name
exportContextSymbols = ('IntRegOperandTraits', 'FloatRegOperandTraits',
'ControlRegOperandTraits', 'MemOperandTraits',
'NPCOperandTraits', 'InstObjParams', 'CodeBlock',
're', 'string')
exportContext = {}
def updateExportContext():
exportContext.update(exportDict(*exportContextSymbols))
exportContext.update(templateMap)
def exportDict(*symNames):
return dict([(s, eval(s)) for s in symNames])
#
# 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.
if ext:
self.eff_ext = ext
else:
self.eff_ext = self.traits.dflt_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.traits.isMem():
self.mem_acc_size = self.traits.makeAccSize(self)
# 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.op_decl = self.traits.makeDecl(self)
if self.is_src:
self.op_rd = self.traits.makeRead(self)
else:
self.op_rd = ''
if self.is_dest:
self.op_wb = self.traits.makeWrite(self)
else:
self.op_wb = ''
class OperandDescriptorList:
# Find all the operands in the given code block. Returns an operand
# descriptor list (instance of class OperandDescriptorList).
def __init__(self, code):
self.items = []
self.bases = {}
# delete comments so we don't match on reg specifiers inside
code = commentRE.sub('', code)
# search for operands
next_pos = 0
while 1:
match = operandsRE.search(code, next_pos)
if not match:
# no more matches: we're done
break
op = match.groups()
# regexp groups are operand full name, base, and extension
(op_full, op_base, op_ext) = op
# if the token following the operand is an assignment, this is
# a destination (LHS), else it's a source (RHS)
is_dest = (assignRE.match(code, match.end()) != None)
is_src = not is_dest
# see if we've already seen this one
op_desc = self.find_base(op_base)
if op_desc:
if op_desc.ext != op_ext:
error(0, 'Inconsistent extensions for operand %s' % \
op_base)
op_desc.is_src = op_desc.is_src or is_src
op_desc.is_dest = op_desc.is_dest or is_dest
else:
# new operand: create new descriptor
op_desc = OperandDescriptor(op_full, op_base, 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.traits.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.traits.isFloatReg():
self.numFPDestRegs += 1
elif op_desc.traits.isIntReg():
self.numIntDestRegs += 1
elif op_desc.traits.isMem():
if self.memOperand:
error(0, "Code block has more than one memory operand.")
self.memOperand = op_desc
# 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.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)
# 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 OperandDescriptor object.)
def substMungedOpNames(code):
return operandsWithExtRE.sub(r'\1', 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 = OperandDescriptorList(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.op_decl = self.operands.concatAttrStrings('op_decl')
self.op_rd = self.operands.concatAttrStrings('op_rd')
self.op_wb = self.operands.concatAttrStrings('op_wb')
self.flags = self.operands.concatAttrLists('flags')
if self.operands.memOperand:
self.mem_acc_size = self.operands.memOperand.mem_acc_size
# 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 = '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'
# Assume all instruction flags are of the form 'IsFoo'
instFlagRE = re.compile(r'Is.*')
# OpClass constants end in 'Op' except No_OpClass
opClassRE = re.compile(r'.*Op|No_OpClass')
class InstObjParams:
def __init__(self, mnem, class_name, base_class = '',
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 = ''
#######################
#
# 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
'''
# 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.
def update_if_needed(file, contents):
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 preprocess_isa_desc(isa_desc):
# Find any includes and include them
pos = 0
while 1:
m = includeRE.search(isa_desc, pos)
if not m:
break
filename = m.group('filename')
print 'Including file "%s"' % filename
try:
isa_desc = isa_desc[:m.start()] + \
'##newfile "' + filename + '"\n' + \
open(filename).read() + \
'##endfile\n' + \
isa_desc[m.end():]
except IOError:
error(0, 'Error including file "%s"' % (filename))
pos = m.start()
return isa_desc
#
# Read in and parse the ISA description.
#
def parse_isa_desc(isa_desc_file, output_dir, include_path):
# set a global var for the input filename... used in error messages
global input_filename
input_filename = isa_desc_file
global fileNameStack
fileNameStack = [(input_filename, 1)]
# Suck the ISA description file in.
input = open(isa_desc_file)
isa_desc = input.read()
input.close()
# Perform Preprocessing
isa_desc = preprocess_isa_desc(isa_desc)
# Parse it.
(isa_name, namespace, global_code, namespace_code) = yacc.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
update_if_needed(output_dir + '/decoder.hh', file_template % vars())
# generate decoder.cc
includes = '#include "%s/decoder.hh"' % include_path
global_output = global_code.decoder_output
namespace_output = namespace_code.decoder_output
namespace_output += namespace_code.decode_block
update_if_needed(output_dir + '/decoder.cc', file_template % vars())
# generate per-cpu exec files
for cpu in CpuModel.list:
includes = '#include "%s/decoder.hh"\n' % include_path
includes += cpu.includes
global_output = global_code.exec_output[cpu.name]
namespace_output = namespace_code.exec_output[cpu.name]
update_if_needed(output_dir + '/' + cpu.filename,
file_template % vars())
# Called as script: get args from command line.
if __name__ == '__main__':
parse_isa_desc(sys.argv[1], sys.argv[2], sys.argv[3])
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