# -*- coding: utf-8 -*- """ Apoo Virtual Processor Copyright (C) 1998-2003 Rogério Reis & Nelma Moreira {rvr,nam}@ncc.up.pt This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. @author: Rogério Reis & Nelma Moreira {rvr,nam}@ncc.up.pt """ from constants import * import string, sys, time, copy __version = "$Id: vpu.py,v 1.49 2006-04-14 21:21:00 rvr Exp $" class Vpu: def __init__(self, n=8, MpMem = {},Inter=None): """This is where all the pseudo-code is specified. Any new intruction added shoud be added to the constants.py module too, where the lexical information resides. @arg n: is the number of registers to support.""" self.reg = [] self.nreg = n for i in range(n): self.reg.append(0) self.RAM = [] self.Prog = [] self.labelp = {} self.labelm = {} self.labelms = {} self.constants = {} self.PC = 0 self.BreakP = [] self.stack = Stack() self.lines = [] self.time0, self.time = 0,0 self.Inter=Inter self.MpMem = copy.deepcopy(MpMem) self.code = {'add':("Reg[A2] = Reg[A2] + Reg[A1]", "incPC()"), 'and':("Reg[A2] = Reg[A1] & Reg[A2]", "incPC()"), 'dec':("Reg[A1] = Reg[A1] - 1", "incPC()"), 'div':("Reg[A2] = Reg[A1] / Reg[A2]", "incPC()"), 'halt':("raise EndOfProgram"), 'inc':("Reg[A1] = Reg[A1] + 1", "incPC()"), 'jneg':("if Reg[A1] < 0:", " if type(A2) == type(''):", " add = self.ParseLabelP(A2)", " else: add = A2", " self.PC = add", "else: self.PC = self.PC + 1"), 'jpos':("if Reg[A1] > 0:", " if type(A2) == type(''):", " add = self.ParseLabelP(A2)", " else: add = A2", " self.PC = add", "else: self.PC = self.PC + 1"), 'jsr':("if type(A1) == type(''):", " add = self.ParseLabelP(A1)", "else: add = A1", "self.stack.push(self.PC + 1)", "self.PC = add"), 'jump':("if type(A1) == type(''):", " try: add = self.labelp[A1]", " except KeyError: raise LabelError", "else: add = A1", "self.PC = add"), 'jumpi':("self.PC = Reg[A1]"), 'jnzero':("if Reg[A1] != 0:", " if type(A2) == type(''):", " add = self.ParseLabelP(A2)", " else: add = i[2]", " self.PC = add", "else: self.PC = self.PC + 1"), 'jzero':("if Reg[A1] == 0:", " if type(A2) == type(''):", " add = self.ParseLabelP(A2)", " else: add = i[2]", " self.PC = add", "else: self.PC = self.PC + 1"), 'load':("if type(A1) == type(''):", " try: add = self.labelm[A1]", " except KeyError: raise LabelError", "else: add = A1", "try: foo = self.MLoad(add)", "except IndexError: raise OutOfMemory(add)", "Reg[A2] = foo", "incPC()"), 'loadi':("add = Reg[A1]", "try: foo = self.MLoad(add)", "except IndexError: raise OutOfMemory(add)", "Reg[A2] = foo", "incPC()"), 'loadn':("if type(A1) == type(''):", " v = self.ParseLabel(A1)", "else: v = A1", "Reg[A2] = v", "incPC()"), 'mod':("Reg[A2] = Reg[A1] % Reg[A2]", "incPC()"), 'mul':("Reg[A2] = Reg[A1] * Reg[A2]", "incPC()"), 'or':("Reg[A2] = Reg[A1] | Reg[A2]", "incPC)"), 'pop':("Reg[A1] = self.stack.pop()", "incPC()"), 'push':("self.stack.push(Reg[A1])", "incPC()"), 'rtn':("self.PC = self.stack.pop()"), 'store':("if type(A2) == type (''):", " try: add = self.labelm[A2]", " except KeyError: raise LabelError", "else: add = A2", "foo = Reg[A1]", "try: self.MStore(add,foo)", "except IndexError: raise OutOfMemory(add)", "incPC()"), 'storei':("try: self.MStore(Reg[A2],Reg[A1])", "except IndexError:", " raise OutOfMemory(Reg[A2])", "incPC()"), 'storen':("if type(A1) == type(''):", " r = self.ParseLabel(A1)", "else: r = A1", "Reg[A2]=r", "incPC()"), 'storer':("Reg[A2] = Reg[A1]", "incPC()"), 'sub':("Reg[A2] = Reg[A1] - Reg[A2]", "incPC()"), 'xor':("Reg[A2] = Reg[A1] ^ Reg[A2]", "incPC()"), 'nop':("incPC()"), 'zero':("Reg[A1] = 0", "incPC()")} for k in self.code.keys(): self.code[k] = expandCode(self.code[k]) def clean(self): """Ensures all the memory areas are clean.""" for i in range(self.nreg): self.reg[i]=0 self.RAM = [] self.Prog = [] self.labelp = {} self.labelm = {} self.labelms = {} self.PC = 0 self.BreakP = [] self.stack = Stack() self.lines = [] self.time0, self.time = 0,0 def __str__(self): """Only used for debugging purposes.""" return str((self.PC,self.reg,self.stack)) def __repr__(self): """Only used for debugging purposes.""" return 'Vpu( %s )'% self.__str__() def MStore(self,add,val): """Store in memory shell that deals with mapped memory """ if add not in self.MpMem.keys(): self.RAM[add] = val else: exec self.MpMem[add][1] def MLoad(self,add): """Load from RAM shell that deals with mapped memory """ if add not in self.MpMem.keys(): return self.RAM[add] else: val = 0 exec self.MpMem[add][0] return val def run(self, MaxSteps=1000): """Starts the execution of the current program. @arg MaxSteps: the maximum allowed number of steps to execute for infinite loop detection.""" i = 0 # self.PC = 0 while self.step() == 1: if i > MaxSteps: raise TooManySteps(i) else: i = i + 1 def setbreak(self,linum): """Create a breakpoint""" if not linum in self.BreakP: self.BreakP.append(linum) def clearbreak(self,linum): """Clear a breakpoint""" if linum in self.BreakP: del(self.BreakP[self.BreakP.index(linum)]) def cont(self,num): i = 0 while self.step() == 1: if i > num: raise TooManySteps(num) i = i + 1 if self.PC in self.BreakP: return def step(self): """basic execution of a step of the program""" self.TimerOn() try: i = self.Prog[self.PC] except IndexError: self.TimerOff() raise OutOfProgram if type(i) == type(''): # no args exec self.code[i] else: exec self.code[i[0]] self.TimerOff() return 1 def incPC(self): self.PC = self.PC + 1 def load(self,program): self.clean() for (n,i) in program: if len(i) < 2: if i[0] == []: raise LabelError(n) else: i.append('nop') if i[1] == 'equ': if len(i) != 3: raise BadArgs(n) if i[0] == []: raise BadArgs(n) else: validateLabelName(i[0],n) if isNumber(i[2]): self.constants[i[0]]= int(i[2]) else: raise BadArgs(n) continue if i[1] == 'const': if len(i) != 3: raise BadArgs(n) if i[0] != []: validateLabelName(i[0],n) self.labelm[i[0]] = len(self.RAM) self.labelms[i[0]] = 1 lastLabel = i[0] else: self.labelms[lastLabel] = self.labelms[lastLabel] + 1 r = charORint(i[2],n) self.RAM.append(r) continue if i[1] == "string": if len(i) != 3: raise BadArgs(n) strarg = validateString(i[2],n) if i[0] != []: validateLabelName(i[0],n) self.labelm[i[0]] = len(self.RAM) self.labelms[i[0]] = len(strarg)+1 for j in strarg: self.RAM.append(ord(j)) self.RAM.append(0) continue if i[1] == 'mem': if len(i) != 3: raise BadArgs(n) try: r = int(i[2]) except ValueError: raise NotInt(n) if i[0] != []: validateLabelName(i[0],n) self.labelm[i[0]] = len(self.RAM) self.labelms[i[0]] = r # this is only for tutor use for foo in range(r): self.RAM.append(0) continue if i[0] != []: validateLabelName(i[0],n) self.labelp[i[0]] = len(self.Prog) self.lines.append(n) if i[1] in inst[0]: # no args if len(i) != 2: raise BadArgs(n) else: self.Prog.append((i[1],)) elif i[1] in inst[1]: # nonreg if len(i) != 3: raise BadArgs(n) else: self.Prog.append((i[1],self.ParseNum(i[2]))) elif i[1] in inst[2]: # reg if len(i) != 3: raise BadArgs(n) r1 = ParseReg(i[2],self.nreg,n) self.Prog.append((i[1],r1)) elif i[1] in inst[3]: # reg reg if len(i) != 4: raise BadArgs(n) r1 = ParseReg(i[2],self.nreg,n) r2 = ParseReg(i[3],self.nreg,n) self.Prog.append((i[1],r1,r2)) elif i[1] in inst[4]: # nonreg reg if len(i) != 4: raise BadArgs(n) r1 = ParseReg(i[3],self.nreg,n) self.Prog.append((i[1],self.ParseNum(i[2]),r1)) elif i[1] in inst[5]: # reg nonreg if len(i) != 4: raise BadArgs(n) r1 = ParseReg(i[2],self.nreg,n) self.Prog.append((i[1],r1,self.ParseNum(i[3]))) else: raise IllInst(n) def ParseNum(self,st): if st in self.constants.keys(): return self.constants[st] elif st[0] in string.digits or st[0] == '-': return int(st) else: return st def ParseLabel(self,st): try: r = self.labelm[st] except KeyError: raise LabelError return r def ParseLabelP(self,st): try: r = self.labelp[st] except KeyError: raise LabelError return r def destructLabel(self,label): if label in self.labelm.keys(): del(self.labelm[label]) if label in self.labelms.keys(): del(self.labelms[label]) def reserveMemory1(self,label,size): self.destructLabel(label) self.labelm[label] = len(self.RAM) for i in range(size): self.RAM.append(0) self.labelms[label] = size def relocateLabel(self,label,dif): for n in self.labelm.keys(): if self.labelm[n] > self.labelm[label] : self.labelm[n] = self.labelm[n] + dif if dif > 0: for i in range(dif): self.RAM.insert(self.labelm[label],0) if dif < 0: self.RAM[(self.labelm[label]+ self.labelms[label] +dif):(self.labelm[label]+ self.labelms[label])]=[] def reserveMemory(self,label,size): if label in self.labelm.keys(): if self.labelms[label] != size: dif = size - self.labelms[label] self.relocateLabel(label,dif) else: for i in range(size): self.RAM[self.labelm[label]+i] = 0 else: self.labelm[label] = len(self.RAM) for i in range(size): self.RAM.append(0) self.labelms[label] = size def TimerInit(self): self.time = 0 def TimerOn(self): self.time0 = time.clock() def TimerOff(self): self.time = self.time + (time.clock() - self.time0) error = 'stack.error' class Stack: """ A class to implement stacks """ def __init__(self, start=[]): self.stack = [] for x in start: self.push(x) self.stack.reverse() # reverse initial stack objects def push(self, object): self.stack = [object] + self.stack def pop(self): if not self.stack: # stack empty! raise 'stack underflow' top, self.stack = self.stack[0], self.stack[1:] return top def top(self): if not self.stack: # stack empty! raise 'stack underflow' return self.stack[0] def empty(self): return not self.stack def popall(self): """empties stack""" self.stack=[] def __repr__(self): return '[Stack:%s]' % self.stack def __cmp__(self, other): return cmp(self.stack, other.stack) # what the heck we are just lists def __len__(self): return len(self.stack) def __add__(self, other): # inst1 + inst2 return Stack(self.stack + other.stack) def __mul__(self, reps): # inst * reps return Stack(self.stack * reps) def __getitem__(self, offset): return self.stack[offset] def __getslice__(self, low, high): return Stack(self.stack[low : high]) def __getattr__(self, name): # inst.sort(), inst.reverse() return getattr(self.stack, name) def ReadProgram(filename): try: input = open(filename, 'r') except IOError: CantRead(filename) program = [] linum = 0 while 1: line = input.readline() linep = [] linum = linum + 1 if not line: break if len(line) == 1: continue line = string.split(line) if line: if line[0][len(line[0])-1] == ':' and line[0][0] != '#': linep.append(line[0][:len(line[0])-1]) elif line[0][0] == '#': continue else: linep.append([]) linep.append(line[0]) for i in range(1,len(line)): if line[i][0] == '#': continue else: linep.append(line[i]) program.append((linum,linep)) return program def CantRead(file): sys.stderr.write("Error: Cannot read file %s\n"%file) sys.exit(1) def ParseReg(st,nreg,line): if st[0] != 'r' and st[0] != 'R': raise IllOperand(line) else: try: i = int(st[1:len(st)]) except ValueError: raise IllOperand(line) if not i in range(nreg): raise IllReg(line) return i def expandCode(list): if type(list) == type(''): return expandCode1(list) else: s = expandCode1(list[0]) for i in list[1:]: s = s + "\n" + expandCode1(i) return s def expandCode1(s): subst = (('A1','i[1]'),('A2','i[2]'),('A3','i[3]'), ('Reg','self.reg'), ('incPC()','self.incPC()'), ('RAM','self.RAM')) for i in subst: s = string.replace(s,i[0],i[1]) return s def isNumber(str): """Verifies if a string is a number representation""" for i in str: if i not in string.digits: return 0 return 1 def validateLabelName(str,linenum): """Verifies if a candidate label name is not of the form R{num}. If the first character is a letter and only contains legal chars.""" if str[0] not in string.letters: raise LabelNameError(linenum) if str[0] in ["R","r"] and isNumber(str[1:]): raise LabelNameError(linenum) for i in str[1:]: if i not in string.letters + string.digits: raise LabelNameError(linenum) def validateString(i,n): arg = "" if i[0] != '"' or i[-1] != '"': raise WrongArg(n) flag = False for c in i[1:-1]: if not flag: if c == "\\": flag= True else: arg += c else: flag = False if c=="t": arg += "\t" if c=="s": arg += " " if c == "n": arg += "\n" if c == "\\": arg += "\\" return arg def charORint(i,n): if i[0] != "'": try: r = int(i) except ValueError: raise WrongArg(n) elif i[-1] != "'": raise WrongArg(n) elif i[1] != "\\" and len(i) != 3: raise WrongArg(n) elif i[1] != "\\": r = ord(i[1]) else: if len(i) != 4: raise WrongArg(n) elif i[2] == "n": r = ord("\n") elif i[2] == "s": r = ord(" ") elif i[2] == "t": r = ord("\t") elif i[2] == "\\": r = ord("\\") else: raise WrongArg(n) return r def isRegName(str): """Verifies if this is a register name.""" if str[0] not in ['r','R']: return 0 elif not isNumber(str[1:]): return 0 return 1