compile_hlasm.py

# Written by Folkert van Heusden
# Released in the public domain

# www.vanheusden.com

# With help from http://www2.latech.edu/~acm/helloworld/asm370.html

import sys

from compile_x86 import CompileToX86

# R6 work register
# R7 pointer

class CompileToHLASM(CompileToX86):
    loopNr = 0
    lnrs = []
    functionsFirst = False
    doOptimize = False

    def header(self):
        print('Brainfuck to HLASM compiler.', file=sys.stderr)

    def get_name():
        return ('hlasm', 'IBM mainframe (system z/zOS) assembly')

    def genindent(self, level):
        return ' ' * (level * 9)

    def emitLInstr(self, label, instr, pars):
        print('%-8s %-5s %s' % (label, instr, pars))

    def emitInstr(self, instr, pars):
        print('%s%-5s %s' % (self.genindent(1), instr, pars))

    def invokeFunction(self, funcNr):
        self.emitInstr('LA', 'R15,f%d' % funcNr)
        self.emitInstr('BALR', 'R14,R15') # branch and link register

    def addToDataPtr(self, n, dot, position):
        ind = self.genindent(1)

        # load address, LA = 12 bit max, LAY = 20 bit max
        print('* add to data ptr')
        self.emitInstr('AHI', 'R7,%d' % n)

    def subFromDataPtr(self, n, dot, position):
        ind = self.genindent(1)

        print('* sub from data ptr')
        self.emitInstr('L', "R6,=F'%d'" % n)
        self.emitInstr('SR', 'R7,R6') # FIXME SR werkt niet zoals verwacht

    def addToData(self, n, dot, position):
        ind = self.genindent(1)

        print('* add to data')
        self.emitInstr('LLGC', 'R6,0(R7)')
        self.emitInstr('AHI', 'R6,%d' % n)
        self.emitInstr('STC', 'R6,0(R7)')

    def subFromData(self, n, dot, position):
        ind = self.genindent(1)

        print('* sub from data')
        self.emitInstr('LLGC', 'R6,0(R7)')
        self.emitInstr('L', "R5,=F'%d'" % n)
        self.emitInstr('SR', 'R6,R5')
        self.emitInstr('STC', 'R6,0(R7)')

    def emitCharacter(self, n, dot):
        ind = self.genindent(1)

        print('* emit character')
        self.emitInstr('LLGC', 'R6,0(R7)')
        self.emitInstr('LA', 'R5,BUFFER')
        self.emitInstr('STC', 'R6,0(R5)')
        self.emitInstr('LA', 'R1,MSGAREA')

        for i in range(0, n):
            self.emitInstr('SVC', '35')

    def startLoop(self, n, position):
        for j in range(0, n):
            print('* start loop')
            loopName = 'WLOOP%d' % self.loopNr
            self.loopNr += 1
            self.lnrs.append(loopName)

            ind = self.genindent(1)
            #self.emitInstr('LA', 'R15,%s_e' % loopName)
            self.emitLInstr(loopName, 'LLGC', 'R6,0(R7)')
            self.emitInstr('C', "R6,=F'0'")
            #self.emitInstr('BZR', 'R15')
            self.emitInstr('BE', '%sE' % loopName)

    def finishLoop(self, n, dot, position):
        for j in range(0, n):
            print('* end loop')
            jb_label = self.lnrs.pop(-1) # jump bakc label
            self.emitInstr('J', '%s' % jb_label)
            self.emitInstr('LTORG', '')

            jb_label_e = jb_label + "E" # break out of while label
            self.emitLInstr(jb_label_e, 'NOP', '')

    def addComment(self, s):
        print('* %s' % s)

    def multilineCommentStart(self):
        print('*')

    def multilineCommentLine(self, s):
        print('* %s' % s)

    def multilineCommentEnd(self):
        print('*')

    def emitFunctions(self):
        for blkLoop in range(0, len(self.blocks)):
            print('f%d NOP' % blkLoop)

            self.translate(self.blocks[blkLoop][0], self.blocks[blkLoop][1])

            print('%sPR' % self.genindent(1))

    def emitProgramTail(self):
        print('* program tail')
        print('         LTORG')
        print('SAVE     DS    18A')
        print('MSGAREA  EQU   *')
        print('         DC    AL2(5)')
        print("         DC    XL2'00'")
        print("BUFFER   DC    C'!'")
        print('data_mem DS    32000C')
        print('         END BEGIN')

    def emitProgramBootstrap(self, file):
        print(f'* This is a translation of "{file}".')
        print('R0 EQU 0')
        print('R1 EQU 1')
        print('R2 EQU 2')
        print('R3 EQU 3')
        print('R4 EQU 4')
        print('R5 EQU 5')
        print('R6 EQU 6')
        print('R7 EQU 7')
        print('R8 EQU 8')
        print('R9 EQU 9')
        print('R10 EQU 10')
        print('R11 EQU 11')
        print('R12 EQU 12')
        print('R13 EQU 13')
        print('R14 EQU 14')
        print('R15 EQU 15')
        print('')

        self.addComments(self.copyrightNotice)
        print('')


    def emitMainFunction(self):
        ind = self.genindent(1)

        print('BF       START 0')
        print('%sPRINT NOGEN' % ind)
        print('BEGIN    SAVE  (14,12)')
        print('%sLR    R12,R15' % ind)
        print('%sBALR  R2,0' % ind)
        print('%sUSING *,R2' % ind)
        print('%sST    R13,SAVE+4' % ind)
        print('%sLA    R11,SAVE' % ind)
        print('%sST    R11,8(13)' % ind)
        print('%sLR    R13,R11' % ind)

        print('%sLA    R7,data_mem' % ind)

        self.translate(0, len(self.allCode))

        print('%sL     R13,SAVE+4' % ind)
        print('%sRETURN (14,12),RC=0' % ind)