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import imp import os import marshal import struct import sys import types from cStringIO import StringIO
from compiler import ast, parse, walk, syntax from compiler import pyassem, misc, future, symbols from compiler.consts import SC_LOCAL, SC_GLOBAL, SC_FREE, SC_CELL from compiler.consts import CO_VARARGS, CO_VARKEYWORDS, CO_NEWLOCALS,\ CO_NESTED, CO_GENERATOR, CO_GENERATOR_ALLOWED, CO_FUTURE_DIVISION from 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 (0,0) : "CALL_FUNCTION", (1,0) : "CALL_FUNCTION_VAR", (0,1) : "CALL_FUNCTION_KW", (1,1) : "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 == "generators": self.graph.setFlag(CO_GENERATOR_ALLOWED)
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) frees = gen.scope.get_free_vars() if frees: for name in frees: self.emit('LOAD_CLOSURE', name) self.emit('LOAD_CONST', gen) self.emit('MAKE_CLOSURE', len(node.defaults)) else: self.emit('LOAD_CONST', gen) self.emit('MAKE_FUNCTION', 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)) frees = gen.scope.get_free_vars() for name in frees: self.emit('LOAD_CLOSURE', name) self.emit('LOAD_CONST', gen) if frees: self.emit('MAKE_CLOSURE', 0) else: self.emit('MAKE_FUNCTION', 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 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 __list_count = 0
def visitListComp(self, node): self.set_lineno(node) # setup list append = "$append%d" % self.__list_count self.__list_count = self.__list_count + 1 self.emit('BUILD_LIST', 0) self.emit('DUP_TOP') self.emit('LOAD_ATTR', 'append') self._implicitNameOp('STORE', append)
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._implicitNameOp('LOAD', append) self.visit(node.expr) self.emit('CALL_FUNCTION', 1) self.emit('POP_TOP')
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) self._implicitNameOp('DELETE', append)
self.__list_count = self.__list_count - 1
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 visitGenExpr(self, node): gen = GenExprCodeGenerator(node, self.scopes, self.class_name, self.get_module()) walk(node.code, gen) gen.finish() self.set_lineno(node) frees = gen.scope.get_free_vars() if frees: for name in frees: self.emit('LOAD_CLOSURE', name) self.emit('LOAD_CONST', gen) self.emit('MAKE_CLOSURE', 0) else: self.emit('LOAD_CONST', gen) self.emit('MAKE_FUNCTION', 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 = 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('YIELD_VALUE')
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) self.emit('LOAD_CONST', None)
def visitGenExprFor(self, node): start = self.newBlock() anchor = self.newBlock()
if node.is_outmost: self.loadName('[outmost-iterable]') 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
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()
# 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) for name, alias in node.names: if VERSION > 1: 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) fromlist = map(lambda (name, alias): name, node.names) if VERSION > 1: 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)
if VERSION > 1: visitAssTuple = _visitAssSequence visitAssList = _visitAssSequence else: def visitAssTuple(self, node): self._visitAssSequence(node, 'UNPACK_TUPLE')
def visitAssList(self, node): self._visitAssSequence(node, 'UNPACK_LIST')
# 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 len(node.subs) > 1: raise SyntaxError, "augmented assignment to tuple is not possible" 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 have_dstar = node.dstar_args is not None 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 aug_flag: self.emit('DUP_TOPX', 2) if len(node.subs) > 1: self.emit('BUILD_TUPLE', len(node.subs)) 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 type(arg) == types.TupleType: 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 type(elt) == types.TupleType: 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 type(elt) == types.StringType: args.append(elt) elif type(elt) == types.TupleType: 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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