Mercurial > lcfOS
view python/c3/typecheck.py @ 202:f22b431f4113
Added arm add instruction
author | Windel Bouwman |
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date | Sat, 15 Jun 2013 10:02:50 +0200 |
parents | 46d62dadd61b |
children | c1ccb1cb4cef |
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from .astnodes import * from .scope import * from .visitor import Visitor def equalTypes(a, b): """ Compare types a and b for equality. Not equal until proven otherwise. """ if type(a) is type(b): if type(a) is BaseType: return a.name == b.name return False class TypeChecker: def __init__(self, diag): self.diag = diag self.visitor = Visitor(self.precheck, self.check2) def error(self, msg, loc): """ Wrapper that registers the message and marks the result invalid """ self.diag.error(msg, loc) self.ok = False def checkPackage(self, pkg): self.ok = True self.visitor.visit(pkg) return self.ok def precheck(self, sym): pass def check2(self, sym): if type(sym) is Function: pass elif type(sym) in [IfStatement, WhileStatement]: if not equalTypes(sym.condition.typ, boolType): self.error('Condition must be of type {0}'.format(boolType), sym.condition.loc) elif type(sym) is Assignment: if not equalTypes(sym.lval.typ, sym.rval.typ): self.error('Cannot assign {0} to {1}'.format(sym.rval.typ, sym.lval.typ), sym.loc) elif type(sym) is ReturnStatement: pass elif type(sym) is FunctionCall: if sym.proc: # Check arguments: ngiv = len(sym.args) ptypes = sym.proc.typ.parametertypes nreq = len(ptypes) if ngiv != nreq: self.error('Function {2}: {0} arguments required, {1} given'.format(nreq, ngiv, sym.proc.name), sym.loc) else: for a, at in zip(sym.args, ptypes): if not equalTypes(a.typ, at): self.error('Got {0}, expected {1}'.format(a.typ, at), a.loc) # determine return type: sym.typ = sym.proc.typ.returntype else: sym.typ = intType elif type(sym) is VariableUse: if sym.target: sym.typ = sym.target.typ else: sym.typ = intType elif type(sym) is Literal: if type(sym.val) is int: sym.typ = intType elif type(sym.val) is float: sym.typ = doubleType elif type(sym.val) is bool: sym.typ = boolType else: self.error('Unknown literal type', sym.loc) elif type(sym) is Binop: if sym.op in ['+', '-', '*', '/']: if equalTypes(sym.a.typ, sym.b.typ): if equalTypes(sym.a.typ, intType): sym.typ = sym.a.typ else: self.error('Can only add integers', sym.loc) sym.typ = intType else: # assume void here? TODO: throw exception! sym.typ = intType self.error('Types unequal', sym.loc) elif sym.op in ['>', '<', '==', '<=', '>=']: sym.typ = boolType if not equalTypes(sym.a.typ, sym.b.typ): self.error('Types unequal', sym.loc) elif sym.op in ['or', 'and']: sym.typ = boolType if not equalTypes(sym.a.typ, boolType): self.error('Must be {0}'.format(boolType), sym.a.loc) if not equalTypes(sym.b.typ, boolType): self.error('Must be {0}'.format(boolType), sym.b.loc) else: sym.typ = voidType print('unknown binop', sym.op) elif type(sym) is Variable: # check initial value type: # TODO pass elif type(sym) is Constant: if not equalTypes(sym.typ, sym.value.typ): self.error('Cannot assign {0} to {1}'.format(sym.value.typ, sym.typ), sym.loc) elif type(sym) in [EmptyStatement, CompoundStatement, Package, Function, FunctionType]: pass else: raise Exception('Unknown type check {0}'.format(sym))