def __init__(self):
self.global_frame = self.new_callframe(None, None) #save global variable.
self.global_code = ByteData() #save global function
#self._active_code = None
self._active_frame = None
self.stdout = self.stdin = self.stderr = None
#temporary used in compile process.
self.statement_stack = []
class Interpreter(object):
"""this module is support to compile AST as byte code, and run byte code."""
def __init__(self):
self.global_frame = self.new_callframe(None, None) #save global variable.
self.global_code = ByteData() #save global function
#self._active_code = None
self._active_frame = None
self.stdout = self.stdin = self.stderr = None
#temporary used in compile process.
self.statement_stack = []
def assemble_ast(self, ast, code=None):
"""convert AST to byte code."""
if code is None: code = ByteData()
assert ast, "AST object is required."
handler = "_c_%s" % type(ast).__name__
if hasattr(self, handler):
getattr(self, handler)(ast, code)
else:
self.error_msg("not found AST handler:%s" % handler, ast.coord)
return code
def interpreter(self, bytecode, frame=None):
if frame is None:
frame = new_callframe(self.global_frame, bytecode)
else:
frame.load_code(bytecode)
#self.frame = frame
self.active_frame(frame)
while self.active_frame() is not None:
op = self.active_frame().next_operation()
if op is None: break
handler_name = "_op_%s" % op
if hasattr(self, handler_name):
handler = getattr(self, handler_name)
handler(self.active_frame(), )
else:
self.error_msg("Not supported operation '%s'" % op)
return frame.return_value
#property
def active_frame(self, frame='null'):
if frame != 'null': self._active_frame = frame
return self._active_frame
def init_builtin_function(self, builtin_list):
for func in builtin_list:
if callable(func):
name = func.func_code.co_name
args_length = func.func_code.co_argcount
decl = Function(name, 'unknown', args_length, None, func)
self.function_reference(name, decl)
elif isinstance(func, types.TupleType):
decl = Function(*func)
self.function_reference(decl.name, decl)
def new_callframe(self, frame, bytedata):
cur_frame = CallFrame(bytedata=bytedata, parent=frame)
return cur_frame
def link_global_code(self, bytecode):
"""load byte data in global scope."""
for name, func in bytecode.functions.iteritems():
if self.global_code.func_reference(name) is None:
self.global_code.func_reference(name, func)
else:
self.error_msg("function %s is defined!" % name)
self.interpreter(bytecode, self.global_frame)
def function_reference(self, name, ref=None):
#It's not a bad code. the ByteData object should not reference a Function that's
# a interpreter concept.
func = None
#if self.bytedata: func = self.bytedata.func_reference(name, ref)
#if func is None:
func = self.global_code.func_reference(name, ref)
if func:
func.inter = self
return func
else:
self.error_msg("function '%s' not define!" % name)
def var_reference(self, name, ref=None):
var = self.active_frame().var_reference(name, ref) or self.global_frame.var_reference(name)
if var:
return var
else:
self.error_msg("variable '%s' not define!" % var)
def error_msg(self, msg, coord=None):
print "msg: %s, coord:%s" % (msg, coord)
def _eval_param(self, frame, val):
"""[C0] --- register
[-1] --- stack tail
[1] --- stack pop
"""
if type(val) == str:
if val[0] == '[':
reg = val[1:-2]
try:
reg = int(reg)
if reg > 0:
for e in range(reg):
reg = frame.pop()
else:
reg = frame.stack[reg]
return reg
except:
return frame.register(reg)
else:
return val
def _c_FunctionDecl(self, funDecl, code):
func_code = ByteData()
param_len = 0
if funDecl.param:
self._c_ParamList(funDecl.param, func_code)
param_len = len(funDecl.param.params)
self.assemble_ast(funDecl.stmt, func_code)
func = Function(funDecl.name.name, funDecl.type, param_len, func_code)
code.func_reference(funDecl.name.name, func)
def _c_FileAST(self, ast, code):
for ext in ast.children():
self.assemble_ast(ext, code)
def _c_ParamList(self, paramList, code):
for param in paramList.children():
self._c_Param(param, code)
def _c_ExprList(self, expr, code):
for e in expr.children():
self.assemble_ast(e, code)
def _c_Param(self, param, code):
init_op = None
if param.out:
op = OP.decl_ref
init_op = OP.save_ref
elif param.var.type == 'array':
op = OP.decl_array
init_op = OP.save_ref #the array is passed as ref.
else:
op = OP.decl_var
init_op = OP.save_var
code.add_operation(op, None, param.type, param.var.name.name)
code.add_operation(init_op, param.var.name.name)
def _c_Compound(self, comp, code):
for decl in comp.decls or []:
self._c_Decl(decl, code)
for stmt in comp.stmts or []:
self.assemble_ast(stmt, code)
def _c_BinaryOp(self, node, code):
op = node.op
#self._c_expression(node.left)
#self._c_expression(node.right)
if op.type == 'OR':
true_label = code.new_label()
self.assemble_ast(node.left, code)
code.add_operation(OP.if_goto, true_label)
code.add_operation(OP.pop)
self.assemble_ast(node.right, code)
code.add_label(true_label)
elif op.type == 'AND':
false_label = code.new_label()
self.assemble_ast(node.left, code)
code.add_operation(OP.unless_goto, false_label)
code.add_operation(OP.pop)
self.assemble_ast(node.right, code)
code.add_label(false_label)
else:
self.assemble_ast(node.left, code)
self.assemble_ast(node.right, code)
code.add_operation(op.type)
def _c_FuncCall(self, func_call, code):
"""
"""
len_args = 0
#args is a ExprList object
if func_call.args:
args_expr = func_call.args.exprs
len_args = len(args_expr)
for expr in args_expr:
self.assemble_ast(expr, code)
code.add_operation(OP.call, func_call.name.name, len_args)
def _c_Decl(self, decl, code):
qualifier = decl.qualifier
type = decl.type
code.update_coord(decl.coord)
def init_array(name, length, init):
code.add_operation(OP.decl_array, qualifier, type, name, length)
if init:
for value in init:
self.assemble_ast(value, code)
code.add_operation(OP.save_array, name, 0, len(init))
def init_var(name, init):
#length = len(init)
code.add_operation(OP.decl_var, qualifier, type, name)
if init:
self.assemble_ast(init, code)
else:
code.add_operation(OP.null_var)
code.add_operation(OP.save_var, name)
for var in decl.vars:
op = OP.decl_array if var.name.type == 'array' else OP.decl_var
if var.name.type == 'array':
length = var.name.index and eval(var.name.index.value) or \
len(var.init or [])
init_array(var.name.name.name, length, var.init)
else:
init_var(var.name.name.name, var.init)
def _c_Constant(self, const, code):
#ord
if const.type == 'char':
code.add_operation(OP.push, ord(const.value))
elif const.type == 'integer':
if const.value.startswith("0x"):
code.add_operation(OP.push, int(const.value, 16))
elif const.value.startswith("0"):
code.add_operation(OP.push, int(const.value, 8))
else:
code.add_operation(OP.push, int(const.value))
elif const.type == 'string':
code.add_operation(OP.push, const.value[1:-1])
else:
self.error_msg("invalid const", const.coord)
def _c_Assignment(self, assign, code):
""" a<-[0],
a[0]<-[0]
"""
self.assemble_ast(assign.value, code)
var = assign.var
if var.type == 'array':
self.assemble_ast(var.index, code)
code.add_operation(OP.pop_reg, "[C0]")
code.add_operation(OP.save_array, var.name.name, '[C0]', 1)
else:
code.add_operation(OP.save_var, var.name.name)
def _c_Varible(self, var, code):
if var.type == 'array':
self.assemble_ast(var.index, code)
code.add_operation(OP.pop_reg, "[C0]")
code.add_operation(OP.load_array, var.name.name, '[C0]', 1)
else:
code.add_operation(OP.load_var, var.name.name)
def _c_If(self, stmt, code):
true_label = code.new_label()
false_label = code.new_label()
end_label = code.new_label()
self.assemble_ast(stmt.cond, code)
code.add_operation(OP.unless_goto, false_label)
self.assemble_ast(stmt.iftrue, code)
code.add_operation(OP.goto, end_label)
code.add_label(false_label)
if stmt.iffalse: self.assemble_ast(stmt.iffalse, code)
code.add_label(end_label)
code.add_operation(OP.pop) #pop the result of expression
def _c_For(self, stmt, code):
self.statement_stack.append(stmt)
if stmt.init:
self.assemble_ast(stmt.init, code)
stmt.cond_label = code.new_label()
stmt.next_label = code.new_label()
stmt.end_label = code.new_label()
stmt.pop_label = code.new_label()
#start condition expression
code.add_label(stmt.cond_label)
if stmt.cond:
self.assemble_ast(stmt.cond, code)
else: #always is true, if omit condtion expression.
code.add_operation(OP.push, 1)
code.add_operation(OP.unless_goto, stmt.pop_label)
#start statement
code.add_operation(OP.pop)
self.assemble_ast(stmt.stmt, code)
#start next statement
code.add_label(stmt.next_label)
if stmt.next:
self.assemble_ast(stmt.next, code)
code.add_operation(OP.goto, stmt.cond_label)
#pop condition result.
code.add_label(stmt.pop_label)
code.add_operation(OP.pop)
code.add_label(stmt.end_label)
self.statement_stack.pop()
def _c_Break(self, st, code):
if len(self.statement_stack) > 0:
stmt = self.statement_stack[-1]
code.add_operation(OP.goto, stmt.end_label)
else:
pass
def _c_Continue(self, st, code):
if len(self.statement_stack) > 0:
stmt = self.statement_stack[-1]
code.add_operation(OP.goto, stmt.next_label)
else:
pass
def _c_Return(self, stmt, code):
if stmt.expr:
self.assemble_ast(stmt.expr, code)
code.add_operation(OP.ret_func)
else:
code.add_operation(OP.ret_void_func)
def _c_While(self, stmt, code):
self.statement_stack.append(stmt)
stmt.cond_label = code.new_label()
stmt.end_label = code.new_label()
stmt.pop_label = code.new_label()
#start condition expression
code.add_label(stmt.cond_label)
self.assemble_ast(stmt.cond, code)
code.add_operation(OP.unless_goto, stmt.pop_label)
#start statement
code.add_operation(OP.pop)
self.assemble_ast(stmt.stmt, code)
code.add_operation(OP.goto, stmt.cond_label)
#pop condition result.
code.add_label(stmt.pop_label)
code.add_operation(OP.pop)
code.add_label(stmt.end_label)
self.statement_stack.pop()
def _op_POP(self, frame):
frame.pop()
def _op_PUSH(self, frame):
data = frame.next_data()
frame.push(data)
def _op_DECL_VAR(self, frame):
#decl variable: OP, qualifier, TYPE, NAME.
const, type, name = frame.next_data(), frame.next_data(), frame.next_data()
#self, name, type, array=False, length=0, const=False
var = InternalVariable(name, type, const == 'const')
self.var_reference(name, var)
def _op_DECL_ARRAY(self, frame):
self._op_DECL_VAR(frame)
def _op_IF_GOTO(self, frame):
label = frame.next_data()
if frame.top(): frame.goto(label)
def _op_UNLESS_GOTO(self, frame):
label = frame.next_data()
if not frame.top(): frame.goto(label)
def _op_LOAD_VAR(self, frame):
name = frame.next_data()
var = self.var_reference(name)
frame.push(var.value)
def _op_LOAD_ARRAY(self, frame):
name = frame.next_data()
index = frame.next_data()
length = frame.next_data()
index = self._eval_param(frame, index)
length = self._eval_param(frame, length)
var = self.var_reference(name)
if var is not None:
value = var.value[index: index + length]
for v in value:
frame.push(v)
if length != 1:
frame.push(length)
def _op_SAVE_VAR(self, frame):
name = frame.next_data()
value = frame.pop()
var = self.var_reference(name)
if var.const and var.value is not None:
self.error_msg("variable '%s' is const." % name)
else:
if var.type == 'string' and isinstance(value, basestring):
var.value = value
elif var.type == 'integer' and isinstance(value, int):
var.value = value
elif var.type == 'float' and isinstance(value, float):
var.value = value
else:
self.error_msg("error variable type '%s' != '%s<%s>'" % (var.type, value, type(value)))
def _op_SAVE_ARRAY(self, frame):
name = frame.next_data()
index = frame.next_data()
length = frame.next_data()
index = self._eval_param(frame, index)
length = self._eval_param(frame, length)
var = self.var_reference(name)
value = []
for v in range(length):
value.insert(0, frame.pop())
var.value[index: index + length] = value
def _op_SAVE_REF(self, frame):
name = frame.next_data()
def _op_CALL(self, frame):
self.return_value = None
name = frame.next_data()
args_length = frame.next_data()
args = []
for e in range(args_length):
args.append(frame.pop())
func = self.function_reference(name)
if func == None:
self.error_msg("function %s not defined before!" % name)
if func.builtIn:
args.reverse()
result = func.call(*args)
if result is not None:
frame.push(result)
else:
frame = self.new_callframe(frame, func.bytedata)
for arg in args: frame.push(arg)
self.active_frame(frame)
def _op_RETURN_FUNC(self, frame):
frame.return_value = value = frame.pop()
parent_frame = frame.parentFrame
if parent_frame is not None:
parent_frame.push(value)
self.active_frame(parent_frame)
def _op_RETURN_VOID_FUNC(self, frame):
frame.return_value = 'void'
self.active_frame(frame.parentFrame)
def _op_PLUS(self, frame):
var1 = frame.pop()
var2 = frame.pop()
frame.push(var2 + var1)
def _op_MINUS(self, frame):
var1 = frame.pop()
var2 = frame.pop()
frame.push(var2 - var1)
def _op_TIMES(self, frame):
var1 = frame.pop()
var2 = frame.pop()
frame.push(var2 * var1)
def _op_DIVIDE(self, frame):
var1 = frame.pop()
var2 = frame.pop()
frame.push(var2 / var1)
def _op_MOD(self, frame):
var1 = frame.pop()
var2 = frame.pop()
frame.push(var2 % var1)
def _op_LT(self, frame):
var1 = frame.pop()
var2 = frame.pop()
frame.push(1 if var2 < var1 else 0)
def _op_LE(self, frame):
var1 = frame.pop()
var2 = frame.pop()
frame.push(1 if var2 <= var1 else 0)
def _op_GT(self, frame):
var1 = frame.pop()
var2 = frame.pop()
frame.push(1 if var2 > var1 else 0)
def _op_GE(self, frame):
var1 = frame.pop()
var2 = frame.pop()
frame.push(1 if var2 >= var1 else 0)
def _op_EQ(self, frame):
var1 = frame.pop()
var2 = frame.pop()
frame.push(1 if var2 == var1 else 0)
def _op_NE(self, frame):
var1 = frame.pop()
var2 = frame.pop()
frame.push(1 if var2 != var1 else 0)
def _op_BOR(self, frame):
var1 = frame.pop()
var2 = frame.pop()
frame.push(var2 | var1)
def _op_BAND(self, frame):
var1 = frame.pop()
var2 = frame.pop()
frame.push(var2 & var1)
def _op_BNOT(self, frame):
var1 = frame.pop()
frame.push(~var1)
def _op_BXOR(self, frame):
var1 = frame.pop()
var2 = frame.pop()
frame.push(var2 ^ var1)
