Python script to remove occurences of 'br undef' in LLVM tests

remove-br-undef.py

# imports for input and regex
import sys
import re

# open each file passed as argument in a loop
for filename in sys.argv[1:]:
    globalCount = 0         # used for numbering replacements in comments
    filebuffer = []         # stores all lines before writing
    localbuffer = []
    flag1 = 0
    brCount = 0
    prevLine = ''

    # open and read the file
    f = open(filename, 'r')
    for line in f:
        if "define" in line:
            if flag1:
                # change the function signature of the previous function to include the new arguments
                pattern = re.compile("define(?P<returnType>.*)@(?P<functionName>.*)\((?P<args>.*)\)")
                m = pattern.match(prevLine)
                if(m != None):
                    comma = "," if m.group('args') != "" else ""
                if(brCount > 0):
                    prevLine = re.sub("define (?P<returnType>.*) @(?P<functionName>.*)\((?P<args>.*)\)", "define \g<returnType> @\g<functionName>(\g<args>"+comma+" %s)" % ', '.join([r'i1 %replaceUndef'+str(x) for x in range(brCount)]),prevLine)
                filebuffer.append(prevLine)
            for b in localbuffer:
                filebuffer.append(b)
            
            prevLine = line
            brCount = 0
            localbuffer = []
            flag1 = 1
        else:
            # replace undef with a new variable in br statements
            if re.match('.*br.*undef',line):
                if re.match('^;',line.strip()):
                    # replace undef in comments
                    line = re.sub('undef', r'[[%replaceUndef'+str(globalCount)+':%.*]]' ,line)
                    globalCount+=1
                    continue
                line = re.sub('undef', r'%replaceUndef'+str(brCount) ,line)
                brCount += 1
            localbuffer.append(line)
    
    if flag1:
        # change the function signature of the last function to include the new arguments
        pattern = re.compile("define(?P<returnType>.*)@(?P<functionName>.*)\((?P<args>.*)\)")
        m = pattern.match(prevLine)
        if(m != None):
            comma = "," if m.group('args') != "" else ""
        if(brCount > 0):
            prevLine = re.sub("define (?P<returnType>.*) @(?P<functionName>.*)\((?P<args>.*)\)", "define \g<returnType> @\g<functionName>(\g<args>"+comma+" %s)" % ', '.join([r'i1 %replaceUndef'+str(x) for x in range(brCount)]),prevLine)
        filebuffer.append(prevLine)
    for b in localbuffer:
        filebuffer.append(b)
            
    f.close()

    # write the file
    f_out = open(filename, 'w')
    f_out.writelines(filebuffer)
    f_out.close()