import imp
import os
import marshal
import struct
import sys
from cStringIO import StringIO
from lib2to3.compiler import ast,parse,walk,syntax
from lib2to3.compiler import pyassem,misc,future,symbols
from lib2to3.compiler.consts import SC_LOCAL,SC_GLOBAL,SC_FREE,SC_CELL
from lib2to3.compiler.consts import (CO_VARARGS,CO_VARKEYWORDS,CO_NEWLOCALS
CO_NESTED, CO_GENERATOR, CO_FUTURE_DIVISION,
CO_FUTURE_ABSIMPORT, CO_FUTURE_WITH_STATEMENT, CO_FUTURE_PRINT_FUNCTION)
from lib2to3.compiler.pyassem import TupleArg
# XXX The version-specific code can go, since this code only works with 2.x.
# Do we have Python 1.x or Python 2.x?
try:
VERSION = sys.version_info[0]
except AttributeError:
VERSION = 1
callfunc_opcode_info = {
# (Have *args, Have **args) : opcode
(0) : "CALL_FUNCTION",
(1) : "CALL_FUNCTION_VAR",
(2) : "CALL_FUNCTION_KW",
(3) : "CALL_FUNCTION_VAR_KW",
}
LOOP = 1
EXCEPT = 2
TRY_FINALLY = 3
END_FINALLY = 4
def compileFile(filename, display=0):
f = open(filename, 'U')
buf = f.read()
f.close()
mod = Module(buf, filename)
try:
mod.compile(display)
except SyntaxError:
raise
else:
f = open(filename + "c", "wb")
mod.dump(f)
f.close()
def compile(source, filename, mode, flags=None, dont_inherit=None):
"""Replacement for builtin compile() function"""
if flags is not None or dont_inherit is not None:
raise RuntimeError, "not implemented yet"
if mode == "single":
gen = Interactive(source, filename)
elif mode == "exec":
gen = Module(source, filename)
elif mode == "eval":
gen = Expression(source, filename)
else:
raise ValueError("compile() 3rd arg must be 'exec' or "
"'eval' or 'single'")
gen.compile()
return gen.code
class AbstractCompileMode:
mode = None # defined by subclass
def __init__(self, source, filename):
self.source = source
self.filename = filename
self.code = None
def _get_tree(self):
tree = parse(self.source, self.mode)
misc.set_filename(self.filename, tree)
syntax.check(tree)
return tree
def compile(self):
pass # implemented by subclass
def getCode(self):
return self.code
class Expression(AbstractCompileMode):
mode = "eval"
def compile(self):
tree = self._get_tree()
gen = ExpressionCodeGenerator(tree)
self.code = gen.getCode()
class Interactive(AbstractCompileMode):
mode = "single"
def compile(self):
tree = self._get_tree()
gen = InteractiveCodeGenerator(tree)
self.code = gen.getCode()
class Module(AbstractCompileMode):
mode = "exec"
def compile(self, display=0):
tree = self._get_tree()
gen = ModuleCodeGenerator(tree)
if display:
import pprint
print pprint.pprint(tree)
self.code = gen.getCode()
def dump(self, f):
f.write(self.getPycHeader())
marshal.dump(self.code, f)
MAGIC = imp.get_magic()
def getPycHeader(self):
# compile.c uses marshal to write a long directly, with
# calling the interface that would also generate a 1-byte code
# to indicate the type of the value. simplest way to get the
# same effect is to call marshal and then skip the code.
mtime = os.path.getmtime(self.filename)
mtime = struct.pack('<i', mtime)
return self.MAGIC + mtime
class LocalNameFinder:
"""Find local names in scope"""
def __init__(self, names=()):
self.names = misc.Set()
self.globals = misc.Set()
for name in names:
self.names.add(name)
# XXX list comprehensions and for loops
def getLocals(self):
for elt in self.globals.elements():
if self.names.has_elt(elt):
self.names.remove(elt)
return self.names
def visitDict(self, node):
pass
def visitGlobal(self, node):
for name in node.names:
self.globals.add(name)
def visitFunction(self, node):
self.names.add(node.name)
def visitLambda(self, node):
pass
def visitImport(self, node):
for name, alias in node.names:
self.names.add(alias or name)
def visitFrom(self, node):
for name, alias in node.names:
self.names.add(alias or name)
def visitClass(self, node):
self.names.add(node.name)
def visitAssName(self, node):
self.names.add(node.name)
def is_constant_false(node):
if isinstance(node, ast.Const):
if not node.value:
return 1
return 0
class CodeGenerator:
"""Defines basic code generator for Python bytecode
This class is an abstract base class. Concrete subclasses must
define an __init__() that defines self.graph and then calls the
__init__() defined in this class.
The concrete class must also define the class attributes
NameFinder, FunctionGen, and ClassGen. These attributes can be
defined in the initClass() method, which is a hook for
initializing these methods after all the classes have been
defined.
"""
optimized = 0 # is namespace access optimized?
__initialized = None
class_name = None # provide default for instance variable
def __init__(self):
if self.__initialized is None:
self.initClass()
self.__class__.__initialized = 1
self.checkClass()
self.locals = misc.Stack()
self.setups = misc.Stack()
self.last_lineno = None
self._setupGraphDelegation()
self._div_op = "BINARY_DIVIDE"
# XXX set flags based on future features
futures = self.get_module().futures
for feature in futures:
if feature == "division":
self.graph.setFlag(CO_FUTURE_DIVISION)
self._div_op = "BINARY_TRUE_DIVIDE"
elif feature == "absolute_import":
self.graph.setFlag(CO_FUTURE_ABSIMPORT)
elif feature == "with_statement":
self.graph.setFlag(CO_FUTURE_WITH_STATEMENT)
elif feature == "print_function":
self.graph.setFlag(CO_FUTURE_PRINT_FUNCTION)
def initClass(self):
"""This method is called once for each class"""
def checkClass(self):
"""Verify that class is constructed correctly"""
try:
assert hasattr(self, 'graph')
assert getattr(self, 'NameFinder')
assert getattr(self, 'FunctionGen')
assert getattr(self, 'ClassGen')
except AssertionError, msg:
intro = "Bad class construction for %s" % self.__class__.__name__
raise AssertionError, intro
def _setupGraphDelegation(self):
self.emit = self.graph.emit
self.newBlock = self.graph.newBlock
self.startBlock = self.graph.startBlock
self.nextBlock = self.graph.nextBlock
self.setDocstring = self.graph.setDocstring
def getCode(self):
"""Return a code object"""
return self.graph.getCode()
def mangle(self, name):
if self.class_name is not None:
return misc.mangle(name, self.class_name)
else:
return name
def parseSymbols(self, tree):
s = symbols.SymbolVisitor()
walk(tree, s)
return s.scopes
def get_module(self):
raise RuntimeError, "should be implemented by subclasses"
# Next five methods handle name access
def isLocalName(self, name):
return self.locals.top().has_elt(name)
def storeName(self, name):
self._nameOp('STORE', name)
def loadName(self, name):
self._nameOp('LOAD', name)
def delName(self, name):
self._nameOp('DELETE', name)
def _nameOp(self, prefix, name):
name = self.mangle(name)
scope = self.scope.check_name(name)
if scope == SC_LOCAL:
if not self.optimized:
self.emit(prefix + '_NAME', name)
else:
self.emit(prefix + '_FAST', name)
elif scope == SC_GLOBAL:
if not self.optimized:
self.emit(prefix + '_NAME', name)
else:
self.emit(prefix + '_GLOBAL', name)
elif scope == SC_FREE or scope == SC_CELL:
self.emit(prefix + '_DEREF', name)
else:
raise RuntimeError, "unsupported scope for var %s: %d" % \
(name, scope)
def _implicitNameOp(self, prefix, name):
"""Emit name ops for names generated implicitly by for loops
The interpreter generates names that start with a period or
dollar sign. The symbol table ignores these names because
they aren't present in the program text.
"""
if self.optimized:
self.emit(prefix + '_FAST', name)
else:
self.emit(prefix + '_NAME', name)
# The set_lineno() function and the explicit emit() calls for
# SET_LINENO below are only used to generate the line number table.
# As of Python 2.3, the interpreter does not have a SET_LINENO
# instruction. pyassem treats SET_LINENO opcodes as a special case.
def set_lineno(self, node, force=False):
"""Emit SET_LINENO if necessary.
The instruction is considered necessary if the node has a
lineno attribute and it is different than the last lineno
emitted.
Returns true if SET_LINENO was emitted.
There are no rules for when an AST node should have a lineno
attribute. The transformer and AST code need to be reviewed
and a consistent policy implemented and documented. Until
then, this method works around missing line numbers.
"""
lineno = getattr(node, 'lineno', None)
if lineno is not None and (lineno != self.last_lineno
or force):
self.emit('SET_LINENO', lineno)
self.last_lineno = lineno
return True
return False
# The first few visitor methods handle nodes that generator new
# code objects. They use class attributes to determine what
# specialized code generators to use.
NameFinder = LocalNameFinder
FunctionGen = None
ClassGen = None
def visitModule(self, node):
self.scopes = self.parseSymbols(node)
self.scope = self.scopes[node]
self.emit('SET_LINENO', 0)
if node.doc:
self.emit('LOAD_CONST', node.doc)
self.storeName('__doc__')
lnf = walk(node.node, self.NameFinder(), verbose=0)
self.locals.push(lnf.getLocals())
self.visit(node.node)
self.emit('LOAD_CONST', None)
self.emit('RETURN_VALUE')
def visitExpression(self, node):
self.set_lineno(node)
self.scopes = self.parseSymbols(node)
self.scope = self.scopes[node]
self.visit(node.node)
self.emit('RETURN_VALUE')
def visitFunction(self, node):
self._visitFuncOrLambda(node, isLambda=0)
if node.doc:
self.setDocstring(node.doc)
self.storeName(node.name)
def visitLambda(self, node):
self._visitFuncOrLambda(node, isLambda=1)
def _visitFuncOrLambda(self, node, isLambda=0):
if not isLambda and node.decorators:
for decorator in node.decorators.nodes:
self.visit(decorator)
ndecorators = len(node.decorators.nodes)
else:
ndecorators = 0
gen = self.FunctionGen(node, self.scopes, isLambda,
self.class_name, self.get_module())
walk(node.code, gen)
gen.finish()
self.set_lineno(node)
for default in node.defaults:
self.visit(default)
self._makeClosure(gen, len(node.defaults))
for i in range(ndecorators):
self.emit('CALL_FUNCTION', 1)
def visitClass(self, node):
gen = self.ClassGen(node, self.scopes,
self.get_module())
walk(node.code, gen)
gen.finish()
self.set_lineno(node)
self.emit('LOAD_CONST', node.name)
for base in node.bases:
self.visit(base)
self.emit('BUILD_TUPLE', len(node.bases))
self._makeClosure(gen, 0)
self.emit('CALL_FUNCTION', 0)
self.emit('BUILD_CLASS')
self.storeName(node.name)
# The rest are standard visitor methods
# The next few implement control-flow statements
def visitIf(self, node):
end = self.newBlock()
numtests = len(node.tests)
for i in range(numtests):
test, suite = node.tests[i]
if is_constant_false(test):
# XXX will need to check generator stuff here
continue
self.set_lineno(test)
self.visit(test)
nextTest = self.newBlock()
self.emit('JUMP_IF_FALSE', nextTest)
self.nextBlock()
self.emit('POP_TOP')
self.visit(suite)
self.emit('JUMP_FORWARD', end)
self.startBlock(nextTest)
self.emit('POP_TOP')
if node.else_:
self.visit(node.else_)
self.nextBlock(end)
def visitWhile(self, node):
self.set_lineno(node)
loop = self.newBlock()
else_ = self.newBlock()
after = self.newBlock()
self.emit('SETUP_LOOP', after)
self.nextBlock(loop)
self.setups.push((LOOP, loop))
self.set_lineno(node, force=True)
self.visit(node.test)
self.emit('JUMP_IF_FALSE', else_ or after)
self.nextBlock()
self.emit('POP_TOP')
self.visit(node.body)
self.emit('JUMP_ABSOLUTE', loop)
self.startBlock(else_) # or just the POPs if not else clause
self.emit('POP_TOP')
self.emit('POP_BLOCK')
self.setups.pop()
if node.else_:
self.visit(node.else_)
self.nextBlock(after)
def visitFor(self, node):
start = self.newBlock()
anchor = self.newBlock()
after = self.newBlock()
self.setups.push((LOOP, start))
self.set_lineno(node)
self.emit('SETUP_LOOP', after)
self.visit(node.list)
self.emit('GET_ITER')
self.nextBlock(start)
self.set_lineno(node, force=1)
self.emit('FOR_ITER', anchor)
self.visit(node.assign)
self.visit(node.body)
self.emit('JUMP_ABSOLUTE', start)
self.nextBlock(anchor)
self.emit('POP_BLOCK')
self.setups.pop()
if node.else_:
self.visit(node.else_)
self.nextBlock(after)
def visitBreak(self, node):
if not self.setups:
raise SyntaxError, "'break' outside loop (%s, %d)" % \
(node.filename, node.lineno)
self.set_lineno(node)
self.emit('BREAK_LOOP')
def visitContinue(self, node):
if not self.setups:
raise SyntaxError, "'continue' outside loop (%s, %d)" % \
(node.filename, node.lineno)
kind, block = self.setups.top()
if kind == LOOP:
self.set_lineno(node)
self.emit('JUMP_ABSOLUTE', block)
self.nextBlock()
elif kind == EXCEPT or kind == TRY_FINALLY:
self.set_lineno(node)
# find the block that starts the loop
top = len(self.setups)
while top > 0:
top = top - 1
kind, loop_block = self.setups[top]
if kind == LOOP:
break
if kind != LOOP:
raise SyntaxError, "'continue' outside loop (%s, %d)" % \
(node.filename, node.lineno)
self.emit('CONTINUE_LOOP', loop_block)
self.nextBlock()
elif kind == END_FINALLY:
msg = "'continue' not allowed inside 'finally' clause (%s, %d)"
raise SyntaxError, msg % (node.filename, node.lineno)
def visitTest(self, node, jump):
end = self.newBlock()
for child in node.nodes[:-1]:
self.visit(child)
self.emit(jump, end)
self.nextBlock()
self.emit('POP_TOP')
self.visit(node.nodes[-1])
self.nextBlock(end)
def visitAnd(self, node):
self.visitTest(node, 'JUMP_IF_FALSE')
def visitOr(self, node):
self.visitTest(node, 'JUMP_IF_TRUE')
def visitIfExp(self, node):
endblock = self.newBlock()
elseblock = self.newBlock()
self.visit(node.test)
self.emit('JUMP_IF_FALSE', elseblock)
self.emit('POP_TOP')
self.visit(node.then)
self.emit('JUMP_FORWARD', endblock)
self.nextBlock(elseblock)
self.emit('POP_TOP')
self.visit(node.else_)
self.nextBlock(endblock)
def visitCompare(self, node):
self.visit(node.expr)
cleanup = self.newBlock()
for op, code in node.ops[:-1]:
self.visit(code)
self.emit('DUP_TOP')
self.emit('ROT_THREE')
self.emit('COMPARE_OP', op)
self.emit('JUMP_IF_FALSE', cleanup)
self.nextBlock()
self.emit('POP_TOP')
# now do the last comparison
if node.ops:
op, code = node.ops[-1]
self.visit(code)
self.emit('COMPARE_OP', op)
if len(node.ops) > 1:
end = self.newBlock()
self.emit('JUMP_FORWARD', end)
self.startBlock(cleanup)
self.emit('ROT_TWO')
self.emit('POP_TOP')
self.nextBlock(end)
# list comprehensions
def visitListComp(self, node):
self.set_lineno(node)
# setup list
self.emit('BUILD_LIST', 0)
stack = []
for i, for_ in zip(range(len(node.quals)), node.quals):
start, anchor = self.visit(for_)
cont = None
for if_ in for_.ifs:
if cont is None:
cont = self.newBlock()
self.visit(if_, cont)
stack.insert(0, (start, cont, anchor))
self.visit(node.expr)
self.emit('LIST_APPEND', len(node.quals) + 1)
for start, cont, anchor in stack:
if cont:
skip_one = self.newBlock()
self.emit('JUMP_FORWARD', skip_one)
self.startBlock(cont)
self.emit('POP_TOP')
self.nextBlock(skip_one)
self.emit('JUMP_ABSOLUTE', start)
self.startBlock(anchor)
def visitListCompFor(self, node):
start = self.newBlock()
anchor = self.newBlock()
self.visit(node.list)
self.emit('GET_ITER')
self.nextBlock(start)
self.set_lineno(node, force=True)
self.emit('FOR_ITER', anchor)
self.nextBlock()
self.visit(node.assign)
return start, anchor
def visitListCompIf(self, node, branch):
self.set_lineno(node, force=True)
self.visit(node.test)
self.emit('JUMP_IF_FALSE', branch)
self.newBlock()
self.emit('POP_TOP')
def _makeClosure(self, gen, args):
frees = gen.scope.get_free_vars()
if frees:
for name in frees:
self.emit('LOAD_CLOSURE', name)
self.emit('BUILD_TUPLE', len(frees))
self.emit('LOAD_CONST', gen)
self.emit('MAKE_CLOSURE', args)
else:
self.emit('LOAD_CONST', gen)
self.emit('MAKE_FUNCTION', args)
def visitGenExpr(self, node):
gen = GenExprCodeGenerator(node, self.scopes, self.class_name,
self.get_module())
walk(node.code, gen)
gen.finish()
self.set_lineno(node)
self._makeClosure(gen, 0)
# precomputation of outmost iterable
self.visit(node.code.quals[0].iter)
self.emit('GET_ITER')
self.emit('CALL_FUNCTION', 1)
def visitGenExprInner(self, node):
self.set_lineno(node)
# setup list
stack = []
for i, for_ in zip(range(len(node.quals)), node.quals):
start, anchor, end = self.visit(for_)
cont = None
for if_ in for_.ifs:
if cont is None:
cont = self.newBlock()
self.visit(if_, cont)
stack.insert(0, (start, cont, anchor, end))
self.visit(node.expr)
self.emit('YIELD_VALUE')
self.emit('POP_TOP')
for start, cont, anchor, end in stack:
if cont:
skip_one = self.newBlock()
self.emit('JUMP_FORWARD', skip_one)
self.startBlock(cont)
self.emit('POP_TOP')
self.nextBlock(skip_one)
self.emit('JUMP_ABSOLUTE', start)
self.startBlock(anchor)
self.emit('POP_BLOCK')
self.setups.pop()
self.startBlock(end)
self.emit('LOAD_CONST', None)
def visitGenExprFor(self, node):
start = self.newBlock()
anchor = self.newBlock()
end = self.newBlock()
self.setups.push((LOOP, start))
self.emit('SETUP_LOOP', end)
if node.is_outmost:
self.loadName('.0')
else:
self.visit(node.iter)
self.emit('GET_ITER')
self.nextBlock(start)
self.set_lineno(node, force=True)
self.emit('FOR_ITER', anchor)
self.nextBlock()
self.visit(node.assign)
return start, anchor, end
def visitGenExprIf(self, node, branch):
self.set_lineno(node, force=True)
self.visit(node.test)
self.emit('JUMP_IF_FALSE', branch)
self.newBlock()
self.emit('POP_TOP')
# exception related
def visitAssert(self, node):
# XXX would be interesting to implement this via a
# transformation of the AST before this stage
if __debug__:
end = self.newBlock()
self.set_lineno(node)
# XXX AssertionError appears to be special case -- it is always
# loaded as a global even if there is a local name. I guess this
# is a sort of renaming op.
self.nextBlock()
self.visit(node.test)
self.emit('JUMP_IF_TRUE', end)
self.nextBlock()
self.emit('POP_TOP')
self.emit('LOAD_GLOBAL', 'AssertionError')
if node.fail:
self.visit(node.fail)
self.emit('RAISE_VARARGS', 2)
else:
self.emit('RAISE_VARARGS', 1)
self.nextBlock(end)
self.emit('POP_TOP')
def visitRaise(self, node):
self.set_lineno(node)
n = 0
if node.expr1:
self.visit(node.expr1)
n = n + 1
if node.expr2:
self.visit(node.expr2)
n = n + 1
if node.expr3:
self.visit(node.expr3)
n = n + 1
self.emit('RAISE_VARARGS', n)
def visitTryExcept(self, node):
body = self.newBlock()
handlers = self.newBlock()
end = self.newBlock()
if node.else_:
lElse = self.newBlock()
else:
lElse = end
self.set_lineno(node)
self.emit('SETUP_EXCEPT', handlers)
self.nextBlock(body)
self.setups.push((EXCEPT, body))
self.visit(node.body)
self.emit('POP_BLOCK')
self.setups.pop()
self.emit('JUMP_FORWARD', lElse)
self.startBlock(handlers)
last = len(node.handlers) - 1
for i in range(len(node.handlers)):
expr, target, body = node.handlers[i]
self.set_lineno(expr)
if expr:
self.emit('DUP_TOP')
self.visit(expr)
self.emit('COMPARE_OP', 'exception match')
next = self.newBlock()
self.emit('JUMP_IF_FALSE', next)
self.nextBlock()
self.emit('POP_TOP')
self.emit('POP_TOP')
if target:
self.visit(target)
else:
self.emit('POP_TOP')
self.emit('POP_TOP')
self.visit(body)
self.emit('JUMP_FORWARD', end)
if expr:
self.nextBlock(next)
else:
self.nextBlock()
if expr: # XXX
self.emit('POP_TOP')
self.emit('END_FINALLY')
if node.else_:
self.nextBlock(lElse)
self.visit(node.else_)
self.nextBlock(end)
def visitTryFinally(self, node):
body = self.newBlock()
final = self.newBlock()
self.set_lineno(node)
self.emit('SETUP_FINALLY', final)
self.nextBlock(body)
self.setups.push((TRY_FINALLY, body))
self.visit(node.body)
self.emit('POP_BLOCK')
self.setups.pop()
self.emit('LOAD_CONST', None)
self.nextBlock(final)
self.setups.push((END_FINALLY, final))
self.visit(node.final)
self.emit('END_FINALLY')
self.setups.pop()
__with_count = 0
def visitWith(self, node):
body = self.newBlock()
final = self.newBlock()
valuevar = "$value%d" % self.__with_count
self.__with_count += 1
self.set_lineno(node)
self.visit(node.expr)
self.emit('DUP_TOP')
self.emit('LOAD_ATTR', '__exit__')
self.emit('ROT_TWO')
self.emit('LOAD_ATTR', '__enter__')
self.emit('CALL_FUNCTION', 0)
if node.vars is None:
self.emit('POP_TOP')
else:
self._implicitNameOp('STORE', valuevar)
self.emit('SETUP_FINALLY', final)
self.nextBlock(body)
self.setups.push((TRY_FINALLY, body))
if node.vars is not None:
self._implicitNameOp('LOAD', valuevar)
self._implicitNameOp('DELETE', valuevar)
self.visit(node.vars)
self.visit(node.body)
self.emit('POP_BLOCK')
self.setups.pop()
self.emit('LOAD_CONST', None)
self.nextBlock(final)
self.setups.push((END_FINALLY, final))
self.emit('WITH_CLEANUP')
self.emit('END_FINALLY')
self.setups.pop()
self.__with_count -= 1
# misc
def visitDiscard(self, node):
self.set_lineno(node)
self.visit(node.expr)
self.emit('POP_TOP')
def visitConst(self, node):
self.emit('LOAD_CONST', node.value)
def visitKeyword(self, node):
self.emit('LOAD_CONST', node.name)
self.visit(node.expr)
def visitGlobal(self, node):
# no code to generate
pass
def visitName(self, node):
self.set_lineno(node)
self.loadName(node.name)
def visitPass(self, node):
self.set_lineno(node)
def visitImport(self, node):
self.set_lineno(node)
if self.graph.checkFlag(CO_FUTURE_ABSIMPORT):
level = 0
else:
level = -1
for name, alias in node.names:
if VERSION > 1:
self.emit('LOAD_CONST', level)
self.emit('LOAD_CONST', None)
self.emit('IMPORT_NAME', name)
mod = name.split(".")[0]
if alias:
self._resolveDots(name)
self.storeName(alias)
else:
self.storeName(mod)
def visitFrom(self, node):
self.set_lineno(node)
level = node.level
if level == 0 and not self.graph.checkFlag(CO_FUTURE_ABSIMPORT):
level = -1
fromlist = map(lambda (name, alias): name, node.names)
if VERSION > 1:
self.emit('LOAD_CONST', level)
self.emit('LOAD_CONST', tuple(fromlist))
self.emit('IMPORT_NAME', node.modname)
for name, alias in node.names:
if VERSION > 1:
if name == '*':
self.namespace = 0
self.emit('IMPORT_STAR')
# There can only be one name w/ from ... import *
assert len(node.names) == 1
return
else:
self.emit('IMPORT_FROM', name)
self._resolveDots(name)
self.storeName(alias or name)
else:
self.emit('IMPORT_FROM', name)
self.emit('POP_TOP')
def _resolveDots(self, name):
elts = name.split(".")
if len(elts) == 1:
return
for elt in elts[1:]:
self.emit('LOAD_ATTR', elt)
def visitGetattr(self, node):
self.visit(node.expr)
self.emit('LOAD_ATTR', self.mangle(node.attrname))
# next five implement assignments
def visitAssign(self, node):
self.set_lineno(node)
self.visit(node.expr)
dups = len(node.nodes) - 1
for i in range(len(node.nodes)):
elt = node.nodes[i]
if i < dups:
self.emit('DUP_TOP')
if isinstance(elt, ast.Node):
self.visit(elt)
def visitAssName(self, node):
if node.flags == 'OP_ASSIGN':
self.storeName(node.name)
elif node.flags == 'OP_DELETE':
self.set_lineno(node)
self.delName(node.name)
else:
print "oops", node.flags
def visitAssAttr(self, node):
self.visit(node.expr)
if node.flags == 'OP_ASSIGN':
self.emit('STORE_ATTR', self.mangle(node.attrname))
elif node.flags == 'OP_DELETE':
self.emit('DELETE_ATTR', self.mangle(node.attrname))
else:
print "warning: unexpected flags:", node.flags
print node
def _visitAssSequence(self, node, op='UNPACK_SEQUENCE'):
if findOp(node) != 'OP_DELETE':
self.emit(op, len(node.nodes))
for child in node.nodes:
self.visit(child)
# assume VERSION > 1
visitAssTuple = _visitAssSequence
visitAssList = _visitAssSequence
# augmented assignment
def visitAugAssign(self, node):
self.set_lineno(node)
aug_node = wrap_aug(node.node)
self.visit(aug_node, "load")
self.visit(node.expr)
self.emit(self._augmented_opcode[node.op])
self.visit(aug_node, "store")
_augmented_opcode = {
'+=' : 'INPLACE_ADD',
'-=' : 'INPLACE_SUBTRACT',
'*=' : 'INPLACE_MULTIPLY',
'/=' : 'INPLACE_DIVIDE',
'//=': 'INPLACE_FLOOR_DIVIDE',
'%=' : 'INPLACE_MODULO',
'**=': 'INPLACE_POWER',
'>>=': 'INPLACE_RSHIFT',
'<<=': 'INPLACE_LSHIFT',
'&=' : 'INPLACE_AND',
'^=' : 'INPLACE_XOR',
'|=' : 'INPLACE_OR',
}
def visitAugName(self, node, mode):
if mode == "load":
self.loadName(node.name)
elif mode == "store":
self.storeName(node.name)
def visitAugGetattr(self, node, mode):
if mode == "load":
self.visit(node.expr)
self.emit('DUP_TOP')
self.emit('LOAD_ATTR', self.mangle(node.attrname))
elif mode == "store":
self.emit('ROT_TWO')
self.emit('STORE_ATTR', self.mangle(node.attrname))
def visitAugSlice(self, node, mode):
if mode == "load":
self.visitSlice(node, 1)
elif mode == "store":
slice = 0
if node.lower:
slice = slice | 1
if node.upper:
slice = slice | 2
if slice == 0:
self.emit('ROT_TWO')
elif slice == 3:
self.emit('ROT_FOUR')
else:
self.emit('ROT_THREE')
self.emit('STORE_SLICE+%d' % slice)
def visitAugSubscript(self, node, mode):
if mode == "load":
self.visitSubscript(node, 1)
elif mode == "store":
self.emit('ROT_THREE')
self.emit('STORE_SUBSCR')
def visitExec(self, node):
self.visit(node.expr)
if node.locals is None:
self.emit('LOAD_CONST', None)
else:
self.visit(node.locals)
if node.globals is None:
self.emit('DUP_TOP')
else:
self.visit(node.globals)
self.emit('EXEC_STMT')
def visitCallFunc(self, node):
pos = 0
kw = 0
self.set_lineno(node)
self.visit(node.node)
for arg in node.args:
self.visit(arg)
if isinstance(arg, ast.Keyword):
kw = kw + 1
else:
pos = pos + 1
if node.star_args is not None:
self.visit(node.star_args)
if node.dstar_args is not None:
self.visit(node.dstar_args)
have_star = node.star_args is not None and 1 or 0
have_dstar = node.dstar_args is not None and 2 or 0
opcode = callfunc_opcode_info[have_star + have_dstar]
self.emit(opcode, kw << 8 | pos)
def visitPrint(self, node, newline=0):
self.set_lineno(node)
if node.dest:
self.visit(node.dest)
for child in node.nodes:
if node.dest:
self.emit('DUP_TOP')
self.visit(child)
if node.dest:
self.emit('ROT_TWO')
self.emit('PRINT_ITEM_TO')
else:
self.emit('PRINT_ITEM')
if node.dest and not newline:
self.emit('POP_TOP')
def visitPrintnl(self, node):
self.visitPrint(node, newline=1)
if node.dest:
self.emit('PRINT_NEWLINE_TO')
else:
self.emit('PRINT_NEWLINE')
def visitReturn(self, node):
self.set_lineno(node)
self.visit(node.value)
self.emit('RETURN_VALUE')
def visitYield(self, node):
self.set_lineno(node)
self.visit(node.value)
self.emit('YIELD_VALUE')
# slice and subscript stuff
def visitSlice(self, node, aug_flag=None):
# aug_flag is used by visitAugSlice
self.visit(node.expr)
slice = 0
if node.lower:
self.visit(node.lower)
slice = slice | 1
if node.upper:
self.visit(node.upper)
slice = slice | 2
if aug_flag:
if slice == 0:
self.emit('DUP_TOP')
elif slice == 3:
self.emit('DUP_TOPX', 3)
else:
self.emit('DUP_TOPX', 2)
if node.flags == 'OP_APPLY':
self.emit('SLICE+%d' % slice)
elif node.flags == 'OP_ASSIGN':
self.emit('STORE_SLICE+%d' % slice)
elif node.flags == 'OP_DELETE':
self.emit('DELETE_SLICE+%d' % slice)
else:
print "weird slice", node.flags
raise
def visitSubscript(self, node, aug_flag=None):
self.visit(node.expr)
for sub in node.subs:
self.visit(sub)
if len(node.subs) > 1:
self.emit('BUILD_TUPLE', len(node.subs))
if aug_flag:
self.emit('DUP_TOPX', 2)
if node.flags == 'OP_APPLY':
self.emit('BINARY_SUBSCR')
elif node.flags == 'OP_ASSIGN':
self.emit('STORE_SUBSCR')
elif node.flags == 'OP_DELETE':
self.emit('DELETE_SUBSCR')
# binary ops
def binaryOp(self, node, op):
self.visit(node.left)
self.visit(node.right)
self.emit(op)
def visitAdd(self, node):
return self.binaryOp(node, 'BINARY_ADD')
def visitSub(self, node):
return self.binaryOp(node, 'BINARY_SUBTRACT')
def visitMul(self, node):
return self.binaryOp(node, 'BINARY_MULTIPLY')
def visitDiv(self, node):
return self.binaryOp(node, self._div_op)
def visitFloorDiv(self, node):
return self.binaryOp(node, 'BINARY_FLOOR_DIVIDE')
def visitMod(self, node):
return self.binaryOp(node, 'BINARY_MODULO')
def visitPower(self, node):
return self.binaryOp(node, 'BINARY_POWER')
def visitLeftShift(self, node):
return self.binaryOp(node, 'BINARY_LSHIFT')
def visitRightShift(self, node):
return self.binaryOp(node, 'BINARY_RSHIFT')
# unary ops
def unaryOp(self, node, op):
self.visit(node.expr)
self.emit(op)
def visitInvert(self, node):
return self.unaryOp(node, 'UNARY_INVERT')
def visitUnarySub(self, node):
return self.unaryOp(node, 'UNARY_NEGATIVE')
def visitUnaryAdd(self, node):
return self.unaryOp(node, 'UNARY_POSITIVE')
def visitUnaryInvert(self, node):
return self.unaryOp(node, 'UNARY_INVERT')
def visitNot(self, node):
return self.unaryOp(node, 'UNARY_NOT')
def visitBackquote(self, node):
return self.unaryOp(node, 'UNARY_CONVERT')
# bit ops
def bitOp(self, nodes, op):
self.visit(nodes[0])
for node in nodes[1:]:
self.visit(node)
self.emit(op)
def visitBitand(self, node):
return self.bitOp(node.nodes, 'BINARY_AND')
def visitBitor(self, node):
return self.bitOp(node.nodes, 'BINARY_OR')
def visitBitxor(self, node):
return self.bitOp(node.nodes, 'BINARY_XOR')
# object constructors
def visitEllipsis(self, node):
self.emit('LOAD_CONST', Ellipsis)
def visitTuple(self, node):
self.set_lineno(node)
for elt in node.nodes:
self.visit(elt)
self.emit('BUILD_TUPLE', len(node.nodes))
def visitList(self, node):
self.set_lineno(node)
for elt in node.nodes:
self.visit(elt)
self.emit('BUILD_LIST', len(node.nodes))
def visitSliceobj(self, node):
for child in node.nodes:
self.visit(child)
self.emit('BUILD_SLICE', len(node.nodes))
def visitDict(self, node):
self.set_lineno(node)
self.emit('BUILD_MAP', 0)
for k, v in node.items:
self.emit('DUP_TOP')
self.visit(k)
self.visit(v)
self.emit('ROT_THREE')
self.emit('STORE_SUBSCR')
class NestedScopeMixin:
"""Defines initClass() for nested scoping (Python 2.2-compatible)"""
def initClass(self):
self.__class__.NameFinder = LocalNameFinder
self.__class__.FunctionGen = FunctionCodeGenerator
self.__class__.ClassGen = ClassCodeGenerator
class ModuleCodeGenerator(NestedScopeMixin, CodeGenerator):
__super_init = CodeGenerator.__init__
scopes = None
def __init__(self, tree):
self.graph = pyassem.PyFlowGraph("<module>", tree.filename)
self.futures = future.find_futures(tree)
self.__super_init()
walk(tree, self)
def get_module(self):
return self
class ExpressionCodeGenerator(NestedScopeMixin, CodeGenerator):
__super_init = CodeGenerator.__init__
scopes = None
futures = ()
def __init__(self, tree):
self.graph = pyassem.PyFlowGraph("<expression>", tree.filename)
self.__super_init()
walk(tree, self)
def get_module(self):
return self
class InteractiveCodeGenerator(NestedScopeMixin, CodeGenerator):
__super_init = CodeGenerator.__init__
scopes = None
futures = ()
def __init__(self, tree):
self.graph = pyassem.PyFlowGraph("<interactive>", tree.filename)
self.__super_init()
self.set_lineno(tree)
walk(tree, self)
self.emit('RETURN_VALUE')
def get_module(self):
return self
def visitDiscard(self, node):
# XXX Discard means it's an expression. Perhaps this is a bad
# name.
self.visit(node.expr)
self.emit('PRINT_EXPR')
class AbstractFunctionCode:
optimized = 1
lambdaCount = 0
def __init__(self, func, scopes, isLambda, class_name, mod):
self.class_name = class_name
self.module = mod
if isLambda:
klass = FunctionCodeGenerator
name = "<lambda.%d>" % klass.lambdaCount
klass.lambdaCount = klass.lambdaCount + 1
else:
name = func.name
args, hasTupleArg = generateArgList(func.argnames)
self.graph = pyassem.PyFlowGraph(name, func.filename, args,
optimized=1)
self.isLambda = isLambda
self.super_init()
if not isLambda and func.doc:
self.setDocstring(func.doc)
lnf = walk(func.code, self.NameFinder(args), verbose=0)
self.locals.push(lnf.getLocals())
if func.varargs:
self.graph.setFlag(CO_VARARGS)
if func.kwargs:
self.graph.setFlag(CO_VARKEYWORDS)
self.set_lineno(func)
if hasTupleArg:
self.generateArgUnpack(func.argnames)
def get_module(self):
return self.module
def finish(self):
self.graph.startExitBlock()
if not self.isLambda:
self.emit('LOAD_CONST', None)
self.emit('RETURN_VALUE')
def generateArgUnpack(self, args):
for i in range(len(args)):
arg = args[i]
if isinstance(arg, tuple):
self.emit('LOAD_FAST', '.%d' % (i * 2))
self.unpackSequence(arg)
def unpackSequence(self, tup):
if VERSION > 1:
self.emit('UNPACK_SEQUENCE', len(tup))
else:
self.emit('UNPACK_TUPLE', len(tup))
for elt in tup:
if isinstance(elt, tuple):
self.unpackSequence(elt)
else:
self._nameOp('STORE', elt)
unpackTuple = unpackSequence
class FunctionCodeGenerator(NestedScopeMixin, AbstractFunctionCode,
CodeGenerator):
super_init = CodeGenerator.__init__ # call be other init
scopes = None
__super_init = AbstractFunctionCode.__init__
def __init__(self, func, scopes, isLambda, class_name, mod):
self.scopes = scopes
self.scope = scopes[func]
self.__super_init(func, scopes, isLambda, class_name, mod)
self.graph.setFreeVars(self.scope.get_free_vars())
self.graph.setCellVars(self.scope.get_cell_vars())
if self.scope.generator is not None:
self.graph.setFlag(CO_GENERATOR)
class GenExprCodeGenerator(NestedScopeMixin, AbstractFunctionCode,
CodeGenerator):
super_init = CodeGenerator.__init__ # call be other init
scopes = None
__super_init = AbstractFunctionCode.__init__
def __init__(self, gexp, scopes, class_name, mod):
self.scopes = scopes
self.scope = scopes[gexp]
self.__super_init(gexp, scopes, 1, class_name, mod)
self.graph.setFreeVars(self.scope.get_free_vars())
self.graph.setCellVars(self.scope.get_cell_vars())
self.graph.setFlag(CO_GENERATOR)
class AbstractClassCode:
def __init__(self, klass, scopes, module):
self.class_name = klass.name
self.module = module
self.graph = pyassem.PyFlowGraph(klass.name, klass.filename,
optimized=0, klass=1)
self.super_init()
lnf = walk(klass.code, self.NameFinder(), verbose=0)
self.locals.push(lnf.getLocals())
self.graph.setFlag(CO_NEWLOCALS)
if klass.doc:
self.setDocstring(klass.doc)
def get_module(self):
return self.module
def finish(self):
self.graph.startExitBlock()
self.emit('LOAD_LOCALS')
self.emit('RETURN_VALUE')
class ClassCodeGenerator(NestedScopeMixin, AbstractClassCode, CodeGenerator):
super_init = CodeGenerator.__init__
scopes = None
__super_init = AbstractClassCode.__init__
def __init__(self, klass, scopes, module):
self.scopes = scopes
self.scope = scopes[klass]
self.__super_init(klass, scopes, module)
self.graph.setFreeVars(self.scope.get_free_vars())
self.graph.setCellVars(self.scope.get_cell_vars())
self.set_lineno(klass)
self.emit("LOAD_GLOBAL", "__name__")
self.storeName("__module__")
if klass.doc:
self.emit("LOAD_CONST", klass.doc)
self.storeName('__doc__')
def generateArgList(arglist):
"""Generate an arg list marking TupleArgs"""
args = []
extra = []
count = 0
for i in range(len(arglist)):
elt = arglist[i]
if isinstance(elt, str):
args.append(elt)
elif isinstance(elt, tuple):
args.append(TupleArg(i * 2, elt))
extra.extend(misc.flatten(elt))
count = count + 1
else:
raise ValueError, "unexpect argument type:", elt
return args + extra, count
def findOp(node):
"""Find the op (DELETE, LOAD, STORE) in an AssTuple tree"""
v = OpFinder()
walk(node, v, verbose=0)
return v.op
class OpFinder:
def __init__(self):
self.op = None
def visitAssName(self, node):
if self.op is None:
self.op = node.flags
elif self.op != node.flags:
raise ValueError, "mixed ops in stmt"
visitAssAttr = visitAssName
visitSubscript = visitAssName
class Delegator:
"""Base class to support delegation for augmented assignment nodes
To generator code for augmented assignments, we use the following
wrapper classes. In visitAugAssign, the left-hand expression node
is visited twice. The first time the visit uses the normal method
for that node . The second time the visit uses a different method
that generates the appropriate code to perform the assignment.
These delegator classes wrap the original AST nodes in order to
support the variant visit methods.
"""
def __init__(self, obj):
self.obj = obj
def __getattr__(self, attr):
return getattr(self.obj, attr)
class AugGetattr(Delegator):
pass
class AugName(Delegator):
pass
class AugSlice(Delegator):
pass
class AugSubscript(Delegator):
pass
wrapper = {
ast.Getattr: AugGetattr,
ast.Name: AugName,
ast.Slice: AugSlice,
ast.Subscript: AugSubscript,
}
def wrap_aug(node):
return wrapper[node.__class__](node)
if __name__ == "__main__":
for file in sys.argv[1:]:
compileFile(file)
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