def is_balanced(exp):
stack = MyStack()
parenthese = {'}': '{', ']': '[', ')': '('}
for c in exp:
if c in parenthese and not stack.is_empty() \
and stack.top() == parenthese[c]:
stack.pop()
else:
stack.push(c)
return stack.is_empty()
def reverseK(queue, k):
if k > queue.size() or k < 0 or queue.is_empty():
return None
stack = MyStack()
for i in range(k):
stack.push(queue.dequeue())
for i in range(k):
queue.enqueue(stack.pop())
for i in range(queue.size() - k):
queue.enqueue(queue.dequeue())
return queue
def next_greater_element(lst):
stack = MyStack()
res = [None] * len(lst)
for i in range(len(lst) - 1, -1, -1):
# iterate backwards
while not stack.is_empty() and stack.peek() <= lst[i]:
stack.pop()
if not stack.is_empty():
# use the top element as nge if available
res[i] = stack.peek()
else:
res[i] = -1
stack.push(lst[i])
return res
def evaluate_post_fix(exp):
ops = ["+", "*", "-", "/"]
stack = MyStack()
for el in exp:
if el == " ":
continue
elif el in ops:
v1, v2 = stack.pop(), stack.pop()
res = eval(f"{v2} {el} {v1}")
stack.push(res)
else:
stack.push(el)
final_num = int(stack.pop())
return final_num
def evaluate_post_fix(exp):
stack = MyStack()
operators = ['+', '-', '*', '/']
for i in exp:
if i.isdigit():
stack.push(int(i))
elif i in operators:
operand1 = stack.pop()
operand2 = stack.pop()
res = operate(operand2, operand1, i)
stack.push(res)
return stack.pop()
def parentheses(str):
s = stack.Stack()
item = {'{': '}', '(': ')'}
for i in range(len(str) - 1):
if str[i] == '{' or str[i] == '(':
s.push(str[i])
if s.peek() is None:
return False
if item[s.peek()] == str[i + 1]:
s.pop()
return s.size == 0
def is_palindrome(str):
s = stack.Stack()
half = int(len(str) / 2)
for i in range(half):
s.push(str[i])
if len(str) % 2 == 1:
half += 1
while s.size != 0:
if s.pop() == str[half]:
half += 1
else:
return False
return True
def __init__(self, InputPro):
self.InputPro = InputPro
self.Terminals = []
self.TerAndEnd = []
self.Virables = []
self.start = ''
self.pList = ProductionList()
self.First = {}
self.Follow = {}
self.string = ''
self.ERROR = False
self.symbolList = []
self.offset = 0
self.domain = 'global'
self.funCode = {}
self.funCode['global'] = []
self.TmpCount = 7
self.errorReason = ''
self.tmpAddNodeList = MyStack()
self.tmpMulNodeList = MyStack()
self.tmpParam = MyStack()
self.tmpSymbolIndex = MyStack()
self.tmpCallNode = MyStack()
self.haveReturn = {}
def dfs(g, vertex):
num_of_vertices = g.vertices
vertices_reached = 0
visited = [False for _ in range(num_of_vertices)]
visited[vertex] = True
stack = MyStack()
stack.push(vertex)
while not stack.is_empty():
current_node = stack.pop()
temp = g.array[current_node].head_node
while temp is not None:
if not visited[temp.data]:
stack.push(temp.data)
visited[temp.data] = True
vertices_reached += 1
temp = temp.next_element
return vertices_reached + 1
def reverseK(queue, k):
if k > queue.size() or k < 0 or queue.is_empty():
return None
stack = MyStack()
new_q = MyQueue()
for i in range(k):
v = queue.dequeue()
stack.push(v)
while not stack.is_empty():
v = stack.pop()
new_q.enqueue(v)
while not queue.is_empty():
v = queue.dequeue()
new_q.enqueue(v)
return new_q
if temp_stack.peek() is not None and value >= temp_stack.peek():
temp_stack.push(value)
else:
while not temp_stack.is_empty():
stack.push(temp_stack.pop())
# place value as the smallest element in temp_stack
temp_stack.push(value)
# Transfer from temp_stack => stack
while not temp_stack.is_empty():
stack.push(temp_stack.pop())
return stack
if __name__ == "__main__":
# Creating and populating the stack
stack = MyStack()
stack.push(2)
stack.push(97)
stack.push(4)
stack.push(42)
stack.push(12)
stack.push(60)
stack.push(23)
# Sorting the stack
stack = sort_stack(stack)
# Printing the sorted stack
print("Stack after sorting")
print([stack.pop() for i in range(stack.size())])
class MyStack:
def reverse_stack(item):
tmp = copy.deepcopy(item)
reverse = stack.Stack()
for i in range(tmp.size):
reverse.push(tmp.pop())
return reverse
def analyze(self):
self.ERROR = False
self.head = node()
self.head.setData('head')
stack = MyStack()
self.lex = LexAn(self.string)
endNode = node()
endNode.setData('#')
stack.push(endNode)
startNode = node()
startNode.setData(self.start)
startNode.setParent(self.head)
self.head.addChildren(startNode)
stack.push(startNode)
self.pointer = 0
self.lineCounter = 1
word, label, now = self.advance()
outResult = ''
while (True):
'''遇注释号跳过'''
if label == '注释号':
word, label, now = self.advance()
continue
'''文件读完,未完成语法分析'''
if word == -1:
self.errorReason += (
'Syntax error, line %d:' % self.lineCounter +
' no end token #\n')
outResult += '\n'
break
'''遇非法字符'''
if label == 'ERROR':
self.errorReason += (
'Syntax error, line %d:' % self.lineCounter +
' skip %s\n' % word)
outResult += '\n'
break
out = ('line %d: ' % self.lineCounter + word + ',' + label)
outResult = outResult + out.ljust(20, ' ')
proResult = False
topNode = stack.pop()
X = topNode.data
if X in self.Terminals:
if X == now:
if X == "标识符":
topNode.parent.addAttributes('place', word)
if topNode.parent.parent.data == '参数':
symbol = {}
symbol['type'] = topNode.parent.parent.children[
0].data
symbol['idName'] = word
symbol['label'] = 'formal'
symbol["domain"] = self.domain
code = self.genCode(op='pop',
result={'reg': self.newTmp()})
symbol['reg'] = code['result']['reg']
self.symbolList.append(symbol)
self.funCode[self.domain].append(code)
if topNode.parent.parent.data == '内部变量声明':
symbol = {}
symbol['type'] = topNode.parent.parent.children[
0].data
symbol['idName'] = word
symbol['offset'] = self.offset
self.offset += 4
symbol['label'] = 'data'
symbol['domain'] = self.domain
self.symbolList.append(symbol)
if X == "num":
topNode.parent.addAttributes('place', {'Imme': word})
if X == ';':
if topNode.parent.data == '赋值语句':
symbolIndex, tag = self.lookUpSymbol(
topNode.parent.children[0].attributes['place'],
self.domain)
if symbolIndex < 0 or (tag != self.domain
and tag != "global"):
self.errorReason += (
"Line%d: undeclared identifier %s\n" %
(self.lineCounter, topNode.parent.
children[0].attributes['place']))
break
if self.symbolList[symbolIndex][
'label'] == 'formal':
code = self.genCode(
op=':=',
arg1=topNode.parent.children[2].
attributes['place'],
result={
'reg':
self.symbolList[symbolIndex]['reg']
})
elif self.symbolList[symbolIndex][
'label'] == 'data':
code = self.genCode(
op=':=',
arg1=topNode.parent.children[2].
attributes['place'],
result={'symbolIndex': symbolIndex})
self.funCode[self.domain].append(code)
elif topNode.parent.data == '返回值':
self.haveReturn[self.domain] = True
if topNode.parent.children[0].data == '表达式':
symbolIndex, _ = self.lookUpSymbol(
self.domain, self.domain)
if self.symbolList[symbolIndex][
'type'] == 'void':
self.errorReason += 'Line%d: void %s can not have a return value.\n ' % (
self.lineCounter, self.domain)
break
self.funCode[self.domain].append(
self.genCode(
op='push',
result=topNode.parent.children[0].
attributes['place']))
else:
symbolIndex, _ = self.lookUpSymbol(
self.domain, self.domain)
if self.symbolList[symbolIndex][
'type'] == 'int':
self.errorReason += 'Line%d: int %s has no return value.\n ' % (
self.lineCounter, self.domain)
break
self.funCode[self.domain].append(
self.genCode(op='jr', result='$ra'))
self.domain = 'global'
if X == ')':
if topNode.parent.data == 'if语句':
self.funCode[self.domain].append(
self.genCode(
op='j' + topNode.parent.children[2].
children[1].children[0].children[0].data,
arg1=topNode.parent.children[2].
children[0].attributes['place'],
arg2=topNode.parent.children[2].children[1]
.children[1].attributes['place'],
result=2))
self.funCode[self.domain].append(
self.genCode(op='j', result=0))
topNode.parent.attributes['false'] = len(
self.funCode[self.domain]) - 1
elif topNode.parent.data == 'while语句':
self.funCode[self.domain].append(
self.genCode(
op='j' + topNode.parent.children[2].
children[1].children[0].children[0].data,
arg1=topNode.parent.children[2].
children[0].attributes['place'],
arg2=topNode.parent.children[2].children[1]
.children[1].attributes['place'],
result=2))
self.funCode[self.domain].append(
self.genCode(op='j', result=0))
topNode.parent.attributes['end'] = len(
self.funCode[self.domain]) - 1
elif topNode.parent.data == '因子':
topNode.parent.attributes[
'place'] = topNode.parent.children[
1].attributes['place']
if X == '}':
if topNode.parent.data == '语句块':
if topNode.parent.parent.data == 'if语句':
self.funCode[self.domain].append(
self.genCode(op='j', result=0))
false = topNode.parent.parent.attributes[
'false']
self.funCode[
self.domain][false]['result'] = len(
self.funCode[self.domain]) - false
topNode.parent.parent.attributes['end'] = len(
self.funCode[self.domain]) - 1
elif topNode.parent.parent.data == 'else语句':
end = topNode.parent.parent.parent.attributes[
'end']
self.funCode[self.domain][end]['result'] = len(
self.funCode[self.domain]) - end
elif topNode.parent.parent.data == 'while语句':
end = topNode.parent.parent.attributes['end']
self.funCode[self.domain].append(
self.genCode(
op='j',
result=end -
len(self.funCode[self.domain]) - 1))
self.funCode[self.domain][end]['result'] = len(
self.funCode[self.domain]) - end
topNode.addAttributes('lineNum', self.lineCounter)
word, label, now = self.advance()
else:
self.errorReason += (
'Syntax error, line %d:' % self.lineCounter +
' expect %s\n' % (X))
outResult += '\n'
break
elif X == '#':
if X == now:
break
else:
self.errorReason += (
'Syntax error, line %d:' % self.lineCounter +
' please check near %s\n' % (word))
outResult += '\n'
break
elif X in self.Virables and self.Table.table[X][now] not in [
' ', 'synch'
]:
if self.Table.table[X][now].right == ['NULL']:
newNode = node()
newNode.setParent(topNode)
newNode.setData('NULL')
topNode.addChildren(newNode)
else:
k = len(self.Table.table[X][now].right) - 1
while (k >= 0):
newNode = node()
newNode.setParent(topNode)
newNode.setData(self.Table.table[X][now].right[k])
topNode.addChildren(newNode)
stack.push(newNode)
k -= 1
topNode.reverseChildren()
if X == '变量声明':
symbol = {}
symbol['type'] = topNode.parent.parent.children[0].data
symbol['idName'] = topNode.parent.parent.children[
1].attributes['place']
symbol['offset'] = self.offset
self.offset += 4
symbol['label'] = 'data'
symbol['domain'] = self.domain
self.symbolList.append(symbol)
elif X == '函数声明' and topNode.parent.data == '声明类型':
symbol = {}
symbol['type'] = topNode.parent.parent.children[0].data
symbol['idName'] = topNode.parent.parent.children[
1].attributes['place']
self.domain = symbol['idName']
self.funCode[self.domain] = []
symbol['label'] = 'func'
symbol['domain'] = self.domain
symbol['offset'] = self.offset
self.offset += 4
self.haveReturn[self.domain] = False
self.symbolList.append(symbol)
elif X == '函数声明' and topNode.parent.data == '声明':
symbol = {}
symbol['type'] = topNode.parent.children[0].data
symbol['idName'] = topNode.parent.children[1].attributes[
'place']
self.domain = symbol['idName']
self.funCode[self.domain] = []
symbol['label'] = 'func'
symbol['domain'] = self.domain
self.haveReturn[self.domain] = True
self.symbolList.append(symbol)
if X == '加法表达式':
self.tmpAddNodeList.push([])
elif X == '加法表达式1':
top = self.tmpAddNodeList.top()
top.append(topNode)
elif X == '项':
self.tmpMulNodeList.push([])
elif X == '项1':
top = self.tmpMulNodeList.top()
top.append(topNode)
if X == '加法表达式1' and topNode.children[0].data == 'NULL':
topAddNode = self.tmpAddNodeList.top()
self.tmpAddNodeList.pop()
if topNode.parent.data == '加法表达式':
topNode.parent.attributes[
'place'] = topNode.parent.children[0].attributes[
'place']
del topAddNode[-1]
for k in range(len(topAddNode)):
addNode = topAddNode[len(topAddNode) - k - 1]
if addNode.children[0].data == '-':
addNode.children[0].data = '减'
newTmp = self.newTmp()
self.funCode[self.domain].append(
self.genCode(op='+',
arg1={'reg': 0},
arg2=addNode.children[1].
attributes['place'],
result={'reg': newTmp}))
self.funCode[self.domain].append(
self.genCode(op='uminus',
result={'reg': newTmp}))
addNode.children[1].attributes['place'] = {
'reg': newTmp
}
if addNode.parent.children[0].data == '-':
addNode.parent.children[0].data = '减'
newTmp = self.newTmp()
self.funCode[self.domain].append(
self.genCode(op='+',
arg1={'reg': 0},
arg2=addNode.parent.children[1].
attributes['place'],
result={'reg': newTmp}))
self.funCode[self.domain].append(
self.genCode(op='uminus',
result={'reg': newTmp}))
addNode.parent.children[1].attributes['place'] = {
'reg': newTmp
}
newTmp = self.newTmp()
if addNode.parent.data == '加法表达式':
code = self.genCode(
'+',
addNode.parent.children[0].attributes['place'],
addNode.children[1].attributes['place'],
{'reg': newTmp})
addNode.parent.addAttributes(
'place', {'reg': newTmp})
else:
code = self.genCode(
'+',
addNode.parent.children[1].attributes['place'],
addNode.children[1].attributes['place'],
{'reg': newTmp})
addNode.parent.children[1].addAttributes(
'place', {'reg': newTmp})
self.funCode[self.domain].append(code)
elif X == '项1' and topNode.children[0].data == 'NULL':
topMulNode = self.tmpMulNodeList.top()
self.tmpMulNodeList.pop()
if topNode.parent.data == '项':
topNode.parent.attributes[
'place'] = topNode.parent.children[0].attributes[
'place']
del topMulNode[-1]
for k in range(len(topMulNode)):
mulNode = topMulNode[len(topMulNode) - k - 1]
newTmp = self.newTmp()
if mulNode.parent.data == '项':
code = self.genCode(
mulNode.children[0].data,
mulNode.parent.children[0].attributes['place'],
mulNode.children[1].attributes['place'],
{'reg': newTmp})
mulNode.parent.addAttributes(
'place', {'reg': newTmp})
else:
code = self.genCode(
mulNode.children[0].data,
mulNode.parent.children[1].attributes['place'],
mulNode.children[1].attributes['place'],
{'reg': newTmp})
mulNode.parent.children[1].addAttributes(
'place', {'reg': newTmp})
self.funCode[self.domain].append(code)
elif X == '表达式1' and topNode.children[0].data == 'NULL':
if topNode.parent.data != '表达式1':
topNode.parent.addAttributes(
'place',
topNode.parent.children[0].attributes['place'])
if topNode.parent.parent.data == '因子':
topNode.parent.parent.addAttributes(
'place',
topNode.parent.children[0].attributes['place'])
if topNode.parent.parent.data in ['实参列表', '实参列表1']:
top = self.tmpParam.top()
top.append(topNode.parent.attributes['place'])
elif X == 'FTYPE' and topNode.children[0].data == 'NULL':
symbolIndex, tag = self.lookUpSymbol(
topNode.parent.children[0].attributes['place'],
self.domain)
if symbolIndex < 0 or (tag != self.domain
and tag != "global"):
self.errorReason += (
"Line%d: undeclared identifier %s\n" %
(self.lineCounter,
topNode.parent.children[0].attributes['place']))
break
if self.symbolList[symbolIndex]['label'] == 'formal':
topNode.parent.addAttributes(
'place',
{'reg': self.symbolList[symbolIndex]['reg']})
elif self.symbolList[symbolIndex]['label'] == 'data':
topNode.parent.addAttributes(
'place', {'symbolIndex': symbolIndex})
elif X == 'call':
symbolIndex, tag = self.lookUpSymbol(
topNode.parent.parent.children[0].attributes['place'],
self.domain)
if symbolIndex < 0:
self.errorReason += (
"Line%d: undeclared function %s\n" %
(self.lineCounter, topNode.parent.parent.
children[0].attributes['place']))
break
self.tmpSymbolIndex.push(symbolIndex)
self.tmpParam.push([])
self.tmpCallNode.push(topNode.parent.parent)
elif X in ['实参列表', '实参列表1'
] and topNode.children[0].data == 'NULL':
paramCount = 0
for s in self.symbolList:
if s['domain'] == self.symbolList[self.tmpSymbolIndex.top()]['idName'] \
and s['label'] == 'formal':
paramCount += 1
topParam = self.tmpParam.top()
topSymbolIndex = self.tmpSymbolIndex.top()
self.tmpParam.pop()
self.tmpSymbolIndex.pop()
if paramCount != len(topParam):
self.errorReason += (
"Line%d: %s function doesn't accept %d parameters\n"
% (self.lineCounter,
self.symbolList[topSymbolIndex]['idName'],
len(topParam)))
break
for i in range(len(topParam)):
self.funCode[self.domain].append(
self.genCode(
op='push',
result=topParam[len(topParam) - i - 1],
))
self.funCode[self.domain].append(
self.genCode(
op='jal',
result='to_%s' %
(self.symbolList[topSymbolIndex]['idName']),
))
topCallNode = self.tmpCallNode.top()
self.tmpCallNode.pop()
newTmp = self.newTmp()
self.funCode[self.domain].append(
self.genCode(op='pop', result={'reg': newTmp}))
topCallNode.addAttributes("place", {'reg': newTmp})
out = ('产生式: ' + self.Table.table[X][now].left + '-->' +
' '.join(self.Table.table[X][now].right))
outResult += out.ljust(40, ' ')
proResult = True
else:
if len(stack.s) == 1 or self.Table.table[X][now] == ' ':
newNode = node()
newNode.setData(X)
stack.push(newNode)
self.errorReason += (
'Syntax error, line %d:' % self.lineCounter +
' skip %s , check near %s\n' % (word, word))
word, label, now = self.advance()
if word == -1:
self.errorReason += (
'Syntax error, line %d:' % self.lineCounter +
' meet the end token # before finishing analysis or no end token #\n'
)
outResult += '\n'
break
break
elif self.Table.table[X][now] == 'synch':
self.errorReason += (
'Syntax error, line %d:' % self.lineCounter +
' pop %s from the stack, check near %s\n' % (X, word))
break
outResult += '\n'
continue
if not proResult:
outResult += ' '.ljust(40)
outResult += (('栈: ' + stack.show()).ljust(40) + '\n')
if self.errorReason == '' and 'main' not in self.funCode.keys():
self.errorReason += 'No main function defined.\n '
if self.errorReason == '':
for key in self.funCode.keys():
if key == 'global': continue
self.funCode[key][0]['entry'] = key
if self.haveReturn[key] == False:
self.errorReason += 'int %s must have a return value.\n' % (
key)
self.arrangeAddr()
return self.errorReason, self.codeList, self.symbolList
else:
return self.errorReason, None, None
class SDTAnalysis:
def __init__(self, InputPro):
self.InputPro = InputPro
self.Terminals = []
self.TerAndEnd = []
self.Virables = []
self.start = ''
self.pList = ProductionList()
self.First = {}
self.Follow = {}
self.string = ''
self.ERROR = False
self.symbolList = []
self.offset = 0
self.domain = 'global'
self.funCode = {}
self.funCode['global'] = []
self.TmpCount = 7
self.errorReason = ''
self.tmpAddNodeList = MyStack()
self.tmpMulNodeList = MyStack()
self.tmpParam = MyStack()
self.tmpSymbolIndex = MyStack()
self.tmpCallNode = MyStack()
self.haveReturn = {}
'''设置起始符号'''
def setStart(self, s):
self.start = s
'''构造产生式表'''
def buildProList(self):
for p in self.InputPro:
self.pList.add(Production(p[0], p[1]))
if p[0] not in self.Virables:
self.Virables.append(p[0])
for p in self.InputPro:
for t in p[1]:
if t not in self.Virables and t not in self.Terminals and t != 'NULL':
self.Terminals.append(t)
self.TerAndEnd = self.Terminals.copy()
self.TerAndEnd.append('#')
'''消除非终结符p的直接左递归'''
def delDirectRecur(self, p):
v = p
vPList = self.pList.getVirablePro(v)
isLeftRecur = False
for p in vPList:
if p.left == p.right[0]:
isLeftRecur = True
if isLeftRecur == True:
new_v = v + '1'
assert new_v not in self.Virables
self.Virables.append(new_v)
for p in vPList:
if p.left == p.right[0]:
self.pList.delete(p)
p.right.remove(p.left)
p.right.append(new_v)
self.pList.add(Production(new_v, p.right))
else:
if p.right == ['NULL']:
p.right = [new_v]
else:
p.right.append(new_v)
self.pList.add(Production(v, p.right))
self.pList.add(Production(new_v, ['NULL']))
'''消除左递归'''
def delLeftRecur(self):
for v in self.Virables:
self.delDirectRecur(v)
'''求FIRST集合'''
def getFirst(self):
first = {}
for v in self.Virables:
first[v] = []
while (True):
Modify = False
for p in self.pList:
if p.right[0] in self.Terminals:
if p.right[0] not in first[p.left]:
first[p.left].append(p.right[0])
Modify = True
elif p.right == ['NULL']:
if 'NULL' not in first[p.left]:
first[p.left].append('NULL')
Modify = True
else:
for i in range(len(p.right)):
if p.right[i] in self.Virables and i == 0:
for t in first[p.right[i]]:
if t not in first[p.left]:
first[p.left].append(t)
Modify = True
if p.right[i] in self.Virables and i >= 1 \
and p.right[i-1] in self.Virables \
and 'NULL' in first[p.right[i-1]]:
for t in first[p.right[i]]:
if t not in first[p.left]:
first[p.left].append(t)
Modify = True
if i == len(p.right) - 1 and \
'NULL' in first[p.right[i]]:
if 'NULL' not in first[p.left]:
first[p.left].append('NULL')
Modify = True
if p.right[i] in self.Terminals and i >= 1 \
and p.right[i - 1] in self.Virables \
and 'NULL' in first[p.right[i - 1]]:
if p.right[i] not in first[p.left]:
first[p.left].append(p.right[i])
Modify = True
break
if not Modify:
self.First = first
break
'''求FOLLOW集合'''
def getFollow(self):
follow = {}
for v in self.Virables:
follow[v] = []
if v == self.start:
follow[v].append('#')
while (True):
Modify = False
for p in self.pList:
i = len(p.right) - 1
rightNull = True
while (i >= 0):
if p.right[i] in self.Terminals:
rightNull = False
if p.right[i] in self.Virables:
if rightNull == True:
for t in follow[p.left]:
if t not in follow[p.right[i]]:
follow[p.right[i]].append(t)
Modify = True
if 'NULL' not in self.First[p.right[i]]:
rightNull = False
if i < len(p.right) - 1 and p.right[
i + 1] in self.Terminals:
if p.right[i + 1] not in follow[p.right[i]]:
follow[p.right[i]].append(p.right[i + 1])
Modify = True
if i < len(p.right) - 1 and p.right[
i + 1] in self.Virables:
for t in self.First[p.right[i + 1]]:
if t not in follow[p.right[i]] and t != 'NULL':
follow[p.right[i]].append(t)
Modify = True
i -= 1
if not Modify:
self.Follow = follow
break
'''求产生式的FIRST集合,之前须调用getFirst()'''
def getProFirst(self, pro):
first = []
i = 0
AllNull = True
while (i < len(pro.right)):
if pro.right[i] in self.Terminals:
if pro.right[i] not in first:
first.append(pro.right[i])
AllNull = False
break
elif pro.right[i] == 'NULL':
break
else:
for t in self.First[pro.right[i]]:
if t not in first:
first.append(t)
if 'NULL' not in self.First[pro.right[i]]:
AllNull = False
break
else:
i += 1
if AllNull:
first.append('NULL')
return first
'''判断是否为LL1文法'''
def isLL1(self):
for v in self.Virables:
pro = self.pList.getVirablePro(v)
for p in pro:
for q in pro:
if p != q:
first_p = self.getProFirst(p)
first_q = self.getProFirst(q)
for t in first_p:
if t in first_q:
print(p.right, q.right)
return False
if 'NULL' in self.First[v]:
for t in self.First[v]:
if t in self.Follow[v]:
print(self.First[v])
print(self.Follow[v])
print(v)
return False
return True
'''构造LL1分析表'''
def buildLL1Table(self):
self.Table = LL1Table(self.Virables)
for p in self.pList:
first_p = self.getProFirst(p)
for t in first_p:
self.Table.add(p.left, t, p)
if 'NULL' in first_p:
for k in self.Follow[p.left]:
self.Table.add(p.left, k, p)
for v in self.Virables:
for t in self.TerAndEnd:
if t not in self.Table.table[v]:
if t in self.Follow[v]:
self.Table.table[v][t] = 'synch'
else:
self.Table.table[v][t] = ' '
def showLL1Table(self):
for v in self.Virables:
for t in self.TerAndEnd:
if self.Table.table[v][t] == ' ' or self.Table.table[v][
t] == 'synch':
print(v, t, self.Table.table[v][t])
else:
print(v, t, self.Table.table[v][t].left,
self.Table.table[v][t].right)
'''读取待分析文件'''
def readFile(self, fileName):
f = open(fileName, 'r')
self.string = f.read()
f.close()
'''读取待分析字符串'''
def getString(self, s):
self.string = s
'''读取下一个词'''
def advance(self):
while (self.pointer < len(self.string)):
if self.string[self.pointer] in ['\n', '\t', ' ']:
if self.string[self.pointer] == '\n':
self.lineCounter += 1
self.pointer += 1
else:
end, label = self.lex.lex_analyze(self.pointer)
word = self.string[self.pointer:end + 1]
self.pointer = end + 1
if label == '标识符':
now = '标识符'
elif label == '数值':
now = 'num'
else:
now = word
return word, label, now
return -1, -1, -1 #越界
'''产生一行中间代码'''
def genCode(self, op=None, arg1=None, arg2=None, result=None):
code = {}
code['addr'] = 0
code['op'] = op
if arg1 != None:
code['arg1'] = arg1
if arg2 != None:
code['arg2'] = arg2
code['result'] = result
return code
'''查询符号表'''
def lookUpSymbol(self, name, domain):
for i in range(len(self.symbolList)):
if self.symbolList[i]["idName"] == name and self.symbolList[i][
"domain"] == domain:
return i, self.symbolList[i]["domain"]
for i in range(len(self.symbolList)):
if self.symbolList[i]["idName"] == name:
return i, self.symbolList[i]["domain"]
return -1, "NULL"
'''申请新的变量'''
def newTmp(self):
if self.TmpCount == 24:
self.TmpCount = 7
self.TmpCount += 1
return self.TmpCount
'''完成翻译后分配地址'''
def arrangeAddr(self):
codeList = []
unknownList = []
funAddr = {}
counter = 0
funAddr['main'] = 100
self.funCode['main'][-1]['result'] = 'end'
for c in self.funCode['main']:
c['addr'] = 100 + counter
if c['op'][0] == 'j':
try:
if c['result'][:3] == 'to_':
c['result'] = c['result'][3:]
unknownList.append(counter)
except:
c['result'] = 100 + counter + c['result']
codeList.append(c)
counter += 1
for key in self.funCode:
if key != "main":
funAddr[key] = 100 + counter
for c in self.funCode[key]:
c['addr'] = 100 + counter
if c['op'][0] == 'j':
try:
if c['result'][:3] == 'to_':
c['result'] = c['result'][3:]
unknownList.append(counter)
except:
c['result'] = 100 + counter + c['result']
codeList.append(c)
counter += 1
for u in unknownList:
if codeList[u]['result'] == "end":
codeList[u]['result'] = len(codeList) + 100
else:
codeList[u]['result'] = funAddr[codeList[u]['result']]
self.codeList = codeList
'''语法制导翻译'''
def analyze(self):
self.ERROR = False
self.head = node()
self.head.setData('head')
stack = MyStack()
self.lex = LexAn(self.string)
endNode = node()
endNode.setData('#')
stack.push(endNode)
startNode = node()
startNode.setData(self.start)
startNode.setParent(self.head)
self.head.addChildren(startNode)
stack.push(startNode)
self.pointer = 0
self.lineCounter = 1
word, label, now = self.advance()
outResult = ''
while (True):
'''遇注释号跳过'''
if label == '注释号':
word, label, now = self.advance()
continue
'''文件读完,未完成语法分析'''
if word == -1:
self.errorReason += (
'Syntax error, line %d:' % self.lineCounter +
' no end token #\n')
outResult += '\n'
break
'''遇非法字符'''
if label == 'ERROR':
self.errorReason += (
'Syntax error, line %d:' % self.lineCounter +
' skip %s\n' % word)
outResult += '\n'
break
out = ('line %d: ' % self.lineCounter + word + ',' + label)
outResult = outResult + out.ljust(20, ' ')
proResult = False
topNode = stack.pop()
X = topNode.data
if X in self.Terminals:
if X == now:
if X == "标识符":
topNode.parent.addAttributes('place', word)
if topNode.parent.parent.data == '参数':
symbol = {}
symbol['type'] = topNode.parent.parent.children[
0].data
symbol['idName'] = word
symbol['label'] = 'formal'
symbol["domain"] = self.domain
code = self.genCode(op='pop',
result={'reg': self.newTmp()})
symbol['reg'] = code['result']['reg']
self.symbolList.append(symbol)
self.funCode[self.domain].append(code)
if topNode.parent.parent.data == '内部变量声明':
symbol = {}
symbol['type'] = topNode.parent.parent.children[
0].data
symbol['idName'] = word
symbol['offset'] = self.offset
self.offset += 4
symbol['label'] = 'data'
symbol['domain'] = self.domain
self.symbolList.append(symbol)
if X == "num":
topNode.parent.addAttributes('place', {'Imme': word})
if X == ';':
if topNode.parent.data == '赋值语句':
symbolIndex, tag = self.lookUpSymbol(
topNode.parent.children[0].attributes['place'],
self.domain)
if symbolIndex < 0 or (tag != self.domain
and tag != "global"):
self.errorReason += (
"Line%d: undeclared identifier %s\n" %
(self.lineCounter, topNode.parent.
children[0].attributes['place']))
break
if self.symbolList[symbolIndex][
'label'] == 'formal':
code = self.genCode(
op=':=',
arg1=topNode.parent.children[2].
attributes['place'],
result={
'reg':
self.symbolList[symbolIndex]['reg']
})
elif self.symbolList[symbolIndex][
'label'] == 'data':
code = self.genCode(
op=':=',
arg1=topNode.parent.children[2].
attributes['place'],
result={'symbolIndex': symbolIndex})
self.funCode[self.domain].append(code)
elif topNode.parent.data == '返回值':
self.haveReturn[self.domain] = True
if topNode.parent.children[0].data == '表达式':
symbolIndex, _ = self.lookUpSymbol(
self.domain, self.domain)
if self.symbolList[symbolIndex][
'type'] == 'void':
self.errorReason += 'Line%d: void %s can not have a return value.\n ' % (
self.lineCounter, self.domain)
break
self.funCode[self.domain].append(
self.genCode(
op='push',
result=topNode.parent.children[0].
attributes['place']))
else:
symbolIndex, _ = self.lookUpSymbol(
self.domain, self.domain)
if self.symbolList[symbolIndex][
'type'] == 'int':
self.errorReason += 'Line%d: int %s has no return value.\n ' % (
self.lineCounter, self.domain)
break
self.funCode[self.domain].append(
self.genCode(op='jr', result='$ra'))
self.domain = 'global'
if X == ')':
if topNode.parent.data == 'if语句':
self.funCode[self.domain].append(
self.genCode(
op='j' + topNode.parent.children[2].
children[1].children[0].children[0].data,
arg1=topNode.parent.children[2].
children[0].attributes['place'],
arg2=topNode.parent.children[2].children[1]
.children[1].attributes['place'],
result=2))
self.funCode[self.domain].append(
self.genCode(op='j', result=0))
topNode.parent.attributes['false'] = len(
self.funCode[self.domain]) - 1
elif topNode.parent.data == 'while语句':
self.funCode[self.domain].append(
self.genCode(
op='j' + topNode.parent.children[2].
children[1].children[0].children[0].data,
arg1=topNode.parent.children[2].
children[0].attributes['place'],
arg2=topNode.parent.children[2].children[1]
.children[1].attributes['place'],
result=2))
self.funCode[self.domain].append(
self.genCode(op='j', result=0))
topNode.parent.attributes['end'] = len(
self.funCode[self.domain]) - 1
elif topNode.parent.data == '因子':
topNode.parent.attributes[
'place'] = topNode.parent.children[
1].attributes['place']
if X == '}':
if topNode.parent.data == '语句块':
if topNode.parent.parent.data == 'if语句':
self.funCode[self.domain].append(
self.genCode(op='j', result=0))
false = topNode.parent.parent.attributes[
'false']
self.funCode[
self.domain][false]['result'] = len(
self.funCode[self.domain]) - false
topNode.parent.parent.attributes['end'] = len(
self.funCode[self.domain]) - 1
elif topNode.parent.parent.data == 'else语句':
end = topNode.parent.parent.parent.attributes[
'end']
self.funCode[self.domain][end]['result'] = len(
self.funCode[self.domain]) - end
elif topNode.parent.parent.data == 'while语句':
end = topNode.parent.parent.attributes['end']
self.funCode[self.domain].append(
self.genCode(
op='j',
result=end -
len(self.funCode[self.domain]) - 1))
self.funCode[self.domain][end]['result'] = len(
self.funCode[self.domain]) - end
topNode.addAttributes('lineNum', self.lineCounter)
word, label, now = self.advance()
else:
self.errorReason += (
'Syntax error, line %d:' % self.lineCounter +
' expect %s\n' % (X))
outResult += '\n'
break
elif X == '#':
if X == now:
break
else:
self.errorReason += (
'Syntax error, line %d:' % self.lineCounter +
' please check near %s\n' % (word))
outResult += '\n'
break
elif X in self.Virables and self.Table.table[X][now] not in [
' ', 'synch'
]:
if self.Table.table[X][now].right == ['NULL']:
newNode = node()
newNode.setParent(topNode)
newNode.setData('NULL')
topNode.addChildren(newNode)
else:
k = len(self.Table.table[X][now].right) - 1
while (k >= 0):
newNode = node()
newNode.setParent(topNode)
newNode.setData(self.Table.table[X][now].right[k])
topNode.addChildren(newNode)
stack.push(newNode)
k -= 1
topNode.reverseChildren()
if X == '变量声明':
symbol = {}
symbol['type'] = topNode.parent.parent.children[0].data
symbol['idName'] = topNode.parent.parent.children[
1].attributes['place']
symbol['offset'] = self.offset
self.offset += 4
symbol['label'] = 'data'
symbol['domain'] = self.domain
self.symbolList.append(symbol)
elif X == '函数声明' and topNode.parent.data == '声明类型':
symbol = {}
symbol['type'] = topNode.parent.parent.children[0].data
symbol['idName'] = topNode.parent.parent.children[
1].attributes['place']
self.domain = symbol['idName']
self.funCode[self.domain] = []
symbol['label'] = 'func'
symbol['domain'] = self.domain
symbol['offset'] = self.offset
self.offset += 4
self.haveReturn[self.domain] = False
self.symbolList.append(symbol)
elif X == '函数声明' and topNode.parent.data == '声明':
symbol = {}
symbol['type'] = topNode.parent.children[0].data
symbol['idName'] = topNode.parent.children[1].attributes[
'place']
self.domain = symbol['idName']
self.funCode[self.domain] = []
symbol['label'] = 'func'
symbol['domain'] = self.domain
self.haveReturn[self.domain] = True
self.symbolList.append(symbol)
if X == '加法表达式':
self.tmpAddNodeList.push([])
elif X == '加法表达式1':
top = self.tmpAddNodeList.top()
top.append(topNode)
elif X == '项':
self.tmpMulNodeList.push([])
elif X == '项1':
top = self.tmpMulNodeList.top()
top.append(topNode)
if X == '加法表达式1' and topNode.children[0].data == 'NULL':
topAddNode = self.tmpAddNodeList.top()
self.tmpAddNodeList.pop()
if topNode.parent.data == '加法表达式':
topNode.parent.attributes[
'place'] = topNode.parent.children[0].attributes[
'place']
del topAddNode[-1]
for k in range(len(topAddNode)):
addNode = topAddNode[len(topAddNode) - k - 1]
if addNode.children[0].data == '-':
addNode.children[0].data = '减'
newTmp = self.newTmp()
self.funCode[self.domain].append(
self.genCode(op='+',
arg1={'reg': 0},
arg2=addNode.children[1].
attributes['place'],
result={'reg': newTmp}))
self.funCode[self.domain].append(
self.genCode(op='uminus',
result={'reg': newTmp}))
addNode.children[1].attributes['place'] = {
'reg': newTmp
}
if addNode.parent.children[0].data == '-':
addNode.parent.children[0].data = '减'
newTmp = self.newTmp()
self.funCode[self.domain].append(
self.genCode(op='+',
arg1={'reg': 0},
arg2=addNode.parent.children[1].
attributes['place'],
result={'reg': newTmp}))
self.funCode[self.domain].append(
self.genCode(op='uminus',
result={'reg': newTmp}))
addNode.parent.children[1].attributes['place'] = {
'reg': newTmp
}
newTmp = self.newTmp()
if addNode.parent.data == '加法表达式':
code = self.genCode(
'+',
addNode.parent.children[0].attributes['place'],
addNode.children[1].attributes['place'],
{'reg': newTmp})
addNode.parent.addAttributes(
'place', {'reg': newTmp})
else:
code = self.genCode(
'+',
addNode.parent.children[1].attributes['place'],
addNode.children[1].attributes['place'],
{'reg': newTmp})
addNode.parent.children[1].addAttributes(
'place', {'reg': newTmp})
self.funCode[self.domain].append(code)
elif X == '项1' and topNode.children[0].data == 'NULL':
topMulNode = self.tmpMulNodeList.top()
self.tmpMulNodeList.pop()
if topNode.parent.data == '项':
topNode.parent.attributes[
'place'] = topNode.parent.children[0].attributes[
'place']
del topMulNode[-1]
for k in range(len(topMulNode)):
mulNode = topMulNode[len(topMulNode) - k - 1]
newTmp = self.newTmp()
if mulNode.parent.data == '项':
code = self.genCode(
mulNode.children[0].data,
mulNode.parent.children[0].attributes['place'],
mulNode.children[1].attributes['place'],
{'reg': newTmp})
mulNode.parent.addAttributes(
'place', {'reg': newTmp})
else:
code = self.genCode(
mulNode.children[0].data,
mulNode.parent.children[1].attributes['place'],
mulNode.children[1].attributes['place'],
{'reg': newTmp})
mulNode.parent.children[1].addAttributes(
'place', {'reg': newTmp})
self.funCode[self.domain].append(code)
elif X == '表达式1' and topNode.children[0].data == 'NULL':
if topNode.parent.data != '表达式1':
topNode.parent.addAttributes(
'place',
topNode.parent.children[0].attributes['place'])
if topNode.parent.parent.data == '因子':
topNode.parent.parent.addAttributes(
'place',
topNode.parent.children[0].attributes['place'])
if topNode.parent.parent.data in ['实参列表', '实参列表1']:
top = self.tmpParam.top()
top.append(topNode.parent.attributes['place'])
elif X == 'FTYPE' and topNode.children[0].data == 'NULL':
symbolIndex, tag = self.lookUpSymbol(
topNode.parent.children[0].attributes['place'],
self.domain)
if symbolIndex < 0 or (tag != self.domain
and tag != "global"):
self.errorReason += (
"Line%d: undeclared identifier %s\n" %
(self.lineCounter,
topNode.parent.children[0].attributes['place']))
break
if self.symbolList[symbolIndex]['label'] == 'formal':
topNode.parent.addAttributes(
'place',
{'reg': self.symbolList[symbolIndex]['reg']})
elif self.symbolList[symbolIndex]['label'] == 'data':
topNode.parent.addAttributes(
'place', {'symbolIndex': symbolIndex})
elif X == 'call':
symbolIndex, tag = self.lookUpSymbol(
topNode.parent.parent.children[0].attributes['place'],
self.domain)
if symbolIndex < 0:
self.errorReason += (
"Line%d: undeclared function %s\n" %
(self.lineCounter, topNode.parent.parent.
children[0].attributes['place']))
break
self.tmpSymbolIndex.push(symbolIndex)
self.tmpParam.push([])
self.tmpCallNode.push(topNode.parent.parent)
elif X in ['实参列表', '实参列表1'
] and topNode.children[0].data == 'NULL':
paramCount = 0
for s in self.symbolList:
if s['domain'] == self.symbolList[self.tmpSymbolIndex.top()]['idName'] \
and s['label'] == 'formal':
paramCount += 1
topParam = self.tmpParam.top()
topSymbolIndex = self.tmpSymbolIndex.top()
self.tmpParam.pop()
self.tmpSymbolIndex.pop()
if paramCount != len(topParam):
self.errorReason += (
"Line%d: %s function doesn't accept %d parameters\n"
% (self.lineCounter,
self.symbolList[topSymbolIndex]['idName'],
len(topParam)))
break
for i in range(len(topParam)):
self.funCode[self.domain].append(
self.genCode(
op='push',
result=topParam[len(topParam) - i - 1],
))
self.funCode[self.domain].append(
self.genCode(
op='jal',
result='to_%s' %
(self.symbolList[topSymbolIndex]['idName']),
))
topCallNode = self.tmpCallNode.top()
self.tmpCallNode.pop()
newTmp = self.newTmp()
self.funCode[self.domain].append(
self.genCode(op='pop', result={'reg': newTmp}))
topCallNode.addAttributes("place", {'reg': newTmp})
out = ('产生式: ' + self.Table.table[X][now].left + '-->' +
' '.join(self.Table.table[X][now].right))
outResult += out.ljust(40, ' ')
proResult = True
else:
if len(stack.s) == 1 or self.Table.table[X][now] == ' ':
newNode = node()
newNode.setData(X)
stack.push(newNode)
self.errorReason += (
'Syntax error, line %d:' % self.lineCounter +
' skip %s , check near %s\n' % (word, word))
word, label, now = self.advance()
if word == -1:
self.errorReason += (
'Syntax error, line %d:' % self.lineCounter +
' meet the end token # before finishing analysis or no end token #\n'
)
outResult += '\n'
break
break
elif self.Table.table[X][now] == 'synch':
self.errorReason += (
'Syntax error, line %d:' % self.lineCounter +
' pop %s from the stack, check near %s\n' % (X, word))
break
outResult += '\n'
continue
if not proResult:
outResult += ' '.ljust(40)
outResult += (('栈: ' + stack.show()).ljust(40) + '\n')
if self.errorReason == '' and 'main' not in self.funCode.keys():
self.errorReason += 'No main function defined.\n '
if self.errorReason == '':
for key in self.funCode.keys():
if key == 'global': continue
self.funCode[key][0]['entry'] = key
if self.haveReturn[key] == False:
self.errorReason += 'int %s must have a return value.\n' % (
key)
self.arrangeAddr()
return self.errorReason, self.codeList, self.symbolList
else:
return self.errorReason, None, None
class SematicAnalysis():
def __init__(self, head):
self.symbolList = []
self.codeList = []
self.treeHead = head
self.offset = 0
self.domain = "global"
self.error = False
self.errorReason = []
self.regCount = 7
self.codeStack = MyStack()
self.paramStack = MyStack()
self.funCode = {}
self.haveReturn = True
def newReg(self):
if self.regCount == 24:
self.regCount = 7
self.regCount += 1
return self.regCount
def lookUpSymbol(self, name, domain):
for i in range(len(self.symbolList)):
if self.symbolList[i]["idName"] == name and self.symbolList[i]["domain"] == domain:
return i, self.symbolList[i]["domain"]
for i in range(len(self.symbolList)):
if self.symbolList[i]["idName"] == name:
return i, self.symbolList[i]["domain"]
return -1, "NULL"
def arrangeAddr(self):
codeList = []
unknownList = []
funAddr = {}
counter = 0
funAddr['main'] = 100
self.funCode['main'][-1]['result'] = 'end'
for c in self.funCode['main']:
c['addr'] = 100 + counter
if c['op'][0] == 'j':
try:
if c['result'][:3] == 'to_':
c['result'] = c['result'][3:]
unknownList.append(counter)
except:
c['result'] = 100 + counter + c['result']
codeList.append(c)
counter += 1
for key in self.funCode:
if key != "main":
funAddr[key] = 100 + counter
for c in self.funCode[key]:
c['addr'] = 100 + counter
if c['op'][0] == 'j':
try:
if c['result'][:3] == 'to_':
c['result'] = c['result'][3:]
unknownList.append(counter)
except:
c['result'] = 100 + counter + c['result']
codeList.append(c)
counter += 1
for u in unknownList:
if codeList[u]['result'] == "end":
codeList[u]['result'] = len(codeList)+ 100
else:
codeList[u]['result'] = funAddr[codeList[u]['result']]
self.codeList = codeList
def genCode(self, op=None, arg1=None, arg2=None, result=None):
code = {}
code['addr'] = 0
code['op'] = op
if arg1 != None:
code['arg1'] = arg1
if arg2 != None:
code['arg2'] = arg2
code['result'] = result
return code
def expDFS(self, p):
if self.error:
return
if p.data == "因子":
if len(p.children) > 1 \
and p.children[1].data == "FTYPE"\
and p.children[1].children[0].data == "call": #过程调用
symbolIndex, _ = self.lookUpSymbol(
p.children[0].children[0].attributes['idName'],
self.domain
)
if symbolIndex < 0:
self.error = True
self.errorReason.append("line %d: 未声明的函数 %s" % (
p.children[0].children[0].attributes['lineNum'],
p.children[0].children[0].attributes['idName']
))
return
tmpCode = []
tmpParam = []
self.codeStack.push(tmpCode)
self.paramStack.push(tmpParam)
self.expDFS(p.children[1].children[0].children[1])
if self.error: return
tmpCode = self.codeStack.pop()
tmpParam = self.paramStack.pop()
paramCount = 0
for s in self.symbolList:
if s['domain'] == self.symbolList[symbolIndex]['idName']\
and s['label'] == 'formal':
paramCount += 1
if paramCount != len(tmpParam): #参数个数不匹配
self.error = True
self.errorReason.append("line %d: %s函数不接受%d个参数"%(
p.children[0].children[0].attributes['lineNum'],
self.symbolList[symbolIndex]['idName'],
len(tmpParam)
))
for i in range(len(tmpParam)):
tmpCode.append(self.genCode(
op='push',
result=tmpParam[i],
))
tmpCode.append(self.genCode(
op='jal',
result="to_" + self.symbolList[symbolIndex]['idName']
))
if self.symbolList[symbolIndex]['label'] == 'formal':
p.addAttributes(
"place",
{'reg': self.symbolList[symbolIndex]['reg']}
)
elif self.symbolList[symbolIndex]['label'] == 'func':
code = self.genCode(op='pop', result={'reg':self.newReg()})
tmpCode.append(code)
p.addAttributes(
"place",
code['result']
)
else:
p.addAttributes(
"place",
{'symbolIndex':symbolIndex}
)
self.codeStack.top().extend(tmpCode)
return
if p.children[0].data == "ID":
symbolIndex, tag = self.lookUpSymbol(
p.children[0].children[0].attributes['idName'],
self.domain
)
if symbolIndex < 0 or (tag != self.domain and tag != "global"):
self.error = True
self.errorReason.append("line %d: 未声明的标识符 %s"%(
p.children[0].children[0].attributes['lineNum'],
p.children[0].children[0].attributes['idName']
))
return
if p.children[0].children[0].attributes['idName'][0] == '-':
if self.symbolList[symbolIndex]['label'] == 'formal':
p.addAttributes(
"place",
{'reg': -self.symbolList[symbolIndex]['reg']}
)
else:
p.addAttributes(
"place",
{'symbolIndex':-symbolIndex}
)
else:
if self.symbolList[symbolIndex]['label'] == 'formal':
p.addAttributes(
"place",
{'reg': self.symbolList[symbolIndex]['reg']}
)
else:
p.addAttributes(
"place",
{'symbolIndex':symbolIndex}
)
if p.children[0].data == "num":
p.addAttributes(
"place",
{'Imme':p.children[0].attributes['NumValue']}
)
for i in range(len(p.children)):
self.expDFS(p.children[i])
if self.error: return
if p.data == '项' or p.data == '加法表达式':
if 'place' in p.children[0].attributes and 'place' not in p.children[1].attributes:
p.addAttributes('place', p.children[0].attributes['place'])
if 'place' in p.children[0].attributes and 'place' in p.children[1].attributes:
if p.children[1].children[0].data == '-':
p.children[1].children[0].data = '+'
p.addAttributes('place', {'reg':self.newReg()})
self.codeStack.top().append(self.genCode(
op = p.children[1].children[0].data,
arg1 = p.children[0].attributes['place'],
arg2 = p.children[1].attributes['place'],
result = p.attributes['place']
))
if p.data == '项1' or p.data == '加法表达式1':
if p.children[0].data == 'NULL':
return
if p.children[0].data == '-':
if 'Imme' in p.children[1].attributes['place']:
new = self.newReg()
code = self.genCode(
op='+',
arg1={'reg':0},
arg2=p.children[1].attributes['place'],
result={'reg':new}
)
self.codeStack.top().append(code)
p.children[1].attributes['place'] = {'reg':new}
code = self.genCode(
op='uminus',
result=p.children[1].attributes['place']
)
self.codeStack.top().append(code)
if 'place' in p.children[1].attributes and 'place' not in p.children[2].attributes:
p.addAttributes('place', p.children[1].attributes['place'])
if 'place' in p.children[1].attributes and 'place' in p.children[2].attributes:
if p.children[2].children[0].data == '-':
p.children[2].children[0].data = '+'
p.addAttributes('place', {'reg':self.newReg()})
code = self.genCode(
op = p.children[2].children[0].data,
arg1 = p.children[1].attributes['place'],
arg2 = p.children[2].attributes['place'],
result = p.attributes['place']
)
p.addAttributes('code', code)
self.codeStack.top().append(code)
if p.data == "表达式" and 'place' in p.children[0].attributes:
p.addAttributes('place', p.children[0].attributes['place'])
if p.data == "表达式1" and p.children[0].data == 'relop':
if 'place' in p.children[1].attributes:
p.addAttributes('place', p.children[1].attributes['place'])
if p.data == "因子":
if 'place' not in p.attributes:
p.addAttributes('place', p.children[1].attributes['place'])
if p.data == "实参列表":
self.paramStack.top().append(p.children[0].attributes['place'])
if p.data == "实参列表1" and p.children[0].data != 'NULL':
self.paramStack.top().append(p.children[1].attributes['place'])
def DFS(self, p):
if self.error:
return
if p.data == "声明":
symbol = {}
symbol["type"] = p.children[0].data
symbol["idName"] = p.children[1].children[0].attributes["idName"]
if symbol["type"] == "int":
symbol["offset"] = self.offset
if p.children[2].children[0].data == "变量声明":
symbol['label'] = 'data'
symbol["domain"] = self.domain
self.offset += 4
if p.children[2].children[0].data == "函数声明": #非void型
self.domain = symbol["idName"]
symbol['label'] = 'func'
symbol["domain"] = symbol["idName"]
self.haveReturn = False
if p.children[2].data == "函数声明": #void型
symbol['label'] = 'func'
self.domain = symbol["idName"]
self.haveReturn = True
symbol['domain'] = symbol["idName"]
self.symbolList.append(symbol)
if p.data == "内部变量声明":
symbol = {}
symbol["type"] = p.children[0].data
symbol["idName"] = p.children[1].children[0].attributes["idName"]
if symbol["type"] == "int":
symbol["offset"] = self.offset
self.offset += 4
if symbol["type"] == "double":
symbol["offset"] = self.offset
self.offset += 8
symbol['label'] = 'data'
symbol["domain"] = self.domain
self.symbolList.append(symbol)
if p.data == "参数":
symbol = {}
symbol["type"] = p.children[0].data
symbol["idName"] = p.children[1].children[0].attributes["idName"]
if symbol["type"] == "int":
symbol["offset"] = self.offset
if symbol["type"] == "double":
symbol["offset"] = self.offset
symbol['label'] = "formal"
symbol["domain"] = self.domain
code = self.genCode(op='pop', result={'reg':self.newReg()})
p.addAttributes('code', [code])
symbol['reg'] = code['result']['reg']
self.symbolList.append(symbol)
if p.data == "赋值语句":
tmpCode = []
self.codeStack.push(tmpCode)
self.expDFS(p.children[2])
if self.error: return
symbolIndex, tag = self.lookUpSymbol(
p.children[0].children[0].attributes['idName'],
self.domain
)
if symbolIndex < 0 or (tag != self.domain and tag != "global"):
self.error = True
self.errorReason.append("line %d: 未声明的标识符 %s" % (
p.children[0].children[0].attributes['lineNum'],
p.children[0].children[0].attributes['idName']
))
return
if self.symbolList[symbolIndex]['label'] == 'formal':
result = {'reg': self.symbolList[symbolIndex]['reg']}
else:
result = {'symbolIndex': symbolIndex}
self.codeStack.top().append(self.genCode(
op = ':=',
arg1 = p.children[2].attributes['place'],
result = result
))
p.addAttributes('code', self.codeStack.pop())
elif p.data == "if语句":
tmpCode = []
self.codeStack.push(tmpCode)
self.expDFS(p.children[2])
if self.error:
return
ifcode = self.codeStack.pop()
ifcode.append(self.genCode(
op = 'j' + p.children[2].children[1].children[0].children[0].data,
arg1 = p.children[2].attributes['place'],
arg2 = p.children[2].children[1].attributes['place'],
result = 2
))
Unknown = len(ifcode)
ifcode.append(self.genCode(op='j', result=-1))
self.DFS(p.children[4]) #搜索if条件成立的语句块
if self.error:return
ifcode.extend(p.children[4].attributes['code'])
self.DFS(p.children[5]) #搜索else下的语句块
if self.error:return
code = self.genCode(op='j')
ifcode.append(code)
ifcode[Unknown]['result'] = len(p.children[4].attributes['code'])+2
if 'code' in p.children[5].attributes:
code['result'] = len(p.children[5].attributes['code']) + 1
ifcode.extend(p.children[5].attributes['code'])
else:
code['result'] = 1
p.addAttributes('code', ifcode.copy())
elif p.data == 'while语句':
tmpCode = []
self.codeStack.push(tmpCode)
self.expDFS(p.children[2])
if self.error:
return
whilecode = self.codeStack.pop()
whilecode.append(self.genCode(
op = 'j'+p.children[2].children[1].children[0].children[0].data,
arg1 = p.children[2].attributes['place'],
arg2 = p.children[2].children[1].attributes['place'],
result = 2
))
Unknown = len(whilecode)
whilecode.append(self.genCode(op='j',result=-1))
self.DFS(p.children[4]) #搜索while条件成立的语句块
if self.error:return
whilecode.extend(p.children[4].attributes['code'])
whilecode.append(self.genCode(op='j', result=-len(whilecode)))
whilecode[Unknown]['result'] = len(whilecode)-Unknown
p.addAttributes('code', whilecode)
elif p.data == "return语句":
if self.haveReturn == False: self.haveReturn = True
tmpCode = []
if p.children[1].children[0].data != ";": #有返回值
symbolIndex, _ = self.lookUpSymbol(self.domain, self.domain)
if self.symbolList[symbolIndex]['type'] == 'void': # 函数必须有返回值，报错
self.error = True
self.errorReason.append('line %d: %s函数不能有返回值' % (
p.children[0].attributes['lineNum'],
self.domain))
return
self.codeStack.push(tmpCode)
self.expDFS(p.children[1].children[0])
if self.error:
return
tmpCode = self.codeStack.pop()
code = self.genCode(op='push', result=p.children[1].children[0].attributes['place'])
tmpCode.append(code)
else: #无返回值
symbolIndex, _ = self.lookUpSymbol(self.domain, self.domain)
if self.symbolList[symbolIndex]['type'] != 'void': #函数必须有返回值，报错
self.error = True
self.errorReason.append('line %d: %s函数必须有返回值'%(
p.children[0].attributes['lineNum'],
self.domain
))
tmpCode.append(self.genCode(op='jr', result='$ra'))
p.addAttributes('code', tmpCode)
else:
for i in range(len(p.children)):
self.DFS(p.children[i])
if self.error: return
if p.data == "语句" and 'code' in p.children[0].attributes:
p.addAttributes('code', p.children[0].attributes['code'])
if p.data == "语句串":
p.addAttributes('code', p.children[0].attributes['code'])
if 'code' in p.children[1].attributes:
p.attributes['code'].extend(p.children[1].attributes['code'])
if p.data == "语句串1" and 'code' in p.children[0].attributes:
p.addAttributes('code', p.children[0].attributes['code'])
if 'code' in p.children[1].attributes:
p.attributes['code'].extend(p.children[1].attributes['code'])
if p.data == "语句块" :
p.addAttributes('code', p.children[2].attributes['code'])
if p.data == 'else语句' and p.children[0].data != 'NULL' and 'code' in p.children[1].attributes:
p.addAttributes('code', p.children[1].attributes['code'])
if p.data == "形参" and 'code' in p.children[0].attributes:
p.addAttributes('code', p.children[0].attributes['code'])
if p.data == "参数列表" and 'code' in p.children[0].attributes:
p.addAttributes('code', p.children[0].attributes['code'])
if 'code' in p.children[1].attributes:
p.attributes['code'].extend(p.children[1].attributes['code'])
if p.data == "参数列表1" and p.children[0].data != "NULL" and 'code' in p.children[1].attributes:
p.addAttributes('code', p.children[1].attributes['code'])
if 'code' in p.children[2].attributes:
p.attributes['code'].extend(p.children[2].attributes['code'])
if p.data == "函数声明":
if self.haveReturn == False:
self.error = 1
self.errorReason.append('%s必须返回一个值'%self.domain)
return
self.domain = "global"
if 'code' in p.children[1].attributes:
p.addAttributes('code', p.children[1].attributes['code'])
else:
p.addAttributes('code',[])
p.attributes['code'].extend(p.children[-1].attributes['code'])
if p.parent.data == "声明类型":
idName = p.parent.parent.children[1].children[0].attributes['idName']
self.funCode[idName] = p.attributes['code']
else:
idName = p.parent.children[1].children[0].attributes['idName']
self.funCode[idName] = p.attributes['code']
self.funCode[idName][0]['entry'] = idName
if p.data == "Program":
if 'main' not in self.funCode:
self.error = True
self.errorReason.append("未定义主函数")
return
self.arrangeAddr()
def analyse(self):
self.DFS(self.treeHead)
return self.symbolList, self.codeList, '\n'.join(self.errorReason)+'\n'
class MinStack:
# Constructor
def __init__(self):
self.main_stack = MyStack()
self.min_stack = MyStack()
def pop(self):
if self.main_stack.is_empty():
return -1
self.min_stack.pop()
return self.main_stack.pop()
def push(self, value):
self.main_stack.push(value)
if self.min_stack.is_empty() or self.min_stack.top() > value:
self.min_stack.push(value)
else:
self.min_stack.push(self.min_stack.top())
def min(self):
if not self.min_stack.is_empty():
return self.min_stack.top()
def analyze(self):
self.ERROR = False
self.head = node()
self.head.setData('head')
stack = MyStack()
self.lex = LexAn(self.string)
endNode = node()
endNode.setData('#')
stack.push(endNode)
startNode = node()
startNode.setData(self.start)
startNode.setParent(self.head)
self.head.addChildren(startNode)
stack.push(startNode)
self.pointer = 0
self.lineCounter = 1
word, label, now = self.advance()
outResult = ''
ErrorResult = ''
while (True):
'''遇注释号跳过'''
if label == '注释号':
word, label, now = self.advance()
continue
'''文件读完,未完成语法分析'''
if word == -1:
ErrorResult += ('line %d:' % self.lineCounter + ' 语法分析错误结束\n')
outResult += '\n'
break
'''遇非法字符'''
if label == 'ERROR':
ErrorResult += ('line %d:' % self.lineCounter +
' 跳过非法词%s\n' % word)
outResult += '\n'
word, label, now = self.advance()
continue
out = ('line %d: ' % self.lineCounter + word + ',' + label)
outResult = outResult + out.ljust(20, ' ')
proResult = False
topNode = stack.pop()
X = topNode.data
if X in self.Terminals:
if X == now:
if X == "标识符":
topNode.addAttributes("idName", word)
if X == "num":
topNode.addAttributes("NumValue", word)
topNode.addAttributes("lineNum", self.lineCounter)
word, label, now = self.advance()
else:
ErrorResult += ('line %d:' % self.lineCounter + ' 期待%s\n' %
(X))
outResult += '\n'
continue
elif X == '#':
if X == now:
break
else:
ErrorResult += ('line %d:' % self.lineCounter +
' 检查%s附近\n' % (word))
outResult += '\n'
break
elif X in self.Virables and self.Table.table[X][now] not in [
' ', 'synch'
]:
if self.Table.table[X][now].right == ['NULL']:
newNode = node()
newNode.setParent(topNode)
newNode.setData('NULL')
topNode.addChildren(newNode)
pass
else:
k = len(self.Table.table[X][now].right) - 1
while (k >= 0):
newNode = node()
newNode.setParent(topNode)
newNode.setData(self.Table.table[X][now].right[k])
topNode.addChildren(newNode)
stack.push(newNode)
k -= 1
topNode.reverseChildren()
out = ('产生式: ' + self.Table.table[X][now].left + '-->' +
' '.join(self.Table.table[X][now].right))
outResult += out.ljust(40, ' ')
proResult = True
else:
if len(stack.s) == 1 or self.Table.table[X][now] == ' ':
newNode = node()
newNode.setData(X)
stack.push(newNode)
ErrorResult += ('line %d:' % self.lineCounter +
' 跳过%s, 检查%s附近\n' % (word, word))
word, label, now = self.advance()
if word == -1:
ErrorResult += ('line %d:' % self.lineCounter +
' 语法分析错误结束\n')
outResult += '\n'
break
elif self.Table.table[X][now] == 'synch':
ErrorResult += ('line %d:' % self.lineCounter +
' %s出栈, 检查%s附近\n' % (X, word))
outResult += '\n'
continue
if not proResult:
outResult += ' '.ljust(40)
outResult += (('栈: ' + stack.show()).ljust(40) + '\n')
if ErrorResult == '':
return ErrorResult, outResult
else:
self.ERROR = True
return ErrorResult, outResult
def setUp(self):
self.testStack = MyStack()
class Test_myStack(unittest.TestCase):
def setUp(self):
self.testStack = MyStack()
def test_pop_emptyStackCase(self):
with self.assertRaises(StackEmptyException):
self.testStack.pop()
def test_pop_done(self):
self.testStack.push('abc')
self.testStack.push('xyz')
self.testStack.push('123')
self.testStack.pop()
self.assertEqual(self.testStack.data, ['abc', 'xyz'])
def test_peek(self):
with self.assertRaises(StackEmptyException):
self.testStack.peek()
def test_push_typeErrorCase(self):
with self.assertRaises(TypeError):
self.testStack.push(10)
def test_push_done(self):
self.testStack.push('abc')
self.testStack.push('xyz')
self.testStack.push('123')
self.testStack.push('456')
self.assertEqual(self.testStack.data, ['abc', 'xyz', '123', '456'])
def test_contain(self):
self.testStack.push('abc')
self.assertTrue(self.testStack.contains('abc'), 'Must be True')
def sort_stack(stack):
sub_stack = MyStack()
if stack.is_empty():
return stack
while not stack.is_empty():
if sub_stack.is_empty() or stack.top() >= sub_stack.top():
sub_stack.push(stack.pop())
continue
val = stack.pop()
while not sub_stack.is_empty():
stack.push(sub_stack.pop())
sub_stack.push(val)
while not sub_stack.is_empty():
stack.push(sub_stack.pop())
return stack
def __init__(self):
self.main_stack = MyStack()
self.min_stack = MyStack()
def sort_stack(stack):
temp_stack = MyStack()
while not stack.is_empty():
value = stack.pop()
# if value is not none and larger, push it at the top of temp_stack
if temp_stack.peek() is not None and value >= temp_stack.peek():
temp_stack.push(value)
else:
while not temp_stack.is_empty():
stack.push(temp_stack.pop())
# place value as the smallest element in temp_stack
temp_stack.push(value)
# Transfer from temp_stack => stack
while not temp_stack.is_empty():
stack.push(temp_stack.pop())
return stack