minnie.tuhs.org/unixen.tar/unixen/PDP-11/Trees/V6/usr/source/fort/fx/fx8.s

Text File | 1975-07-17 | 2.7 KB | 270 lines

/
/

/ fx8 -- read source line

.globl    getline
.globl    isagn
.globl    levzer

.globl    error
.globl    getc
.globl    chrtab

getline:
    mov    r3,-(sp)
    clr    holquo
    clr    r3        / line number
    clr    line
    mov    $line,r1
1:
    jsr    pc,get
    sub    $'0,r0
    cmp    r0,$9
    bhi    1f
    mpy    $10.,r3
    add    r0,r3
    br    1b
1:
    add    $'0,r0
    movb    r0,ch
    mov    r3,efno
1:
    mov    lino, ifno
    inc    ifno
    jsr    pc,get
    cmp    r0,$'\n        / nl
    beq    1f
    cmp    r0,$''
    beq    2f
    cmp    r0,$'"
    bne    3f
2:
    mov    r0,holquo
    add    $4,r1        / room for h count
    mov    r1,-(sp)
2:
    jsr    pc,get
    cmp    r0,$'\n
    beq    4f
    cmp    r0,holquo
    beq    2f
    bis    $200,r0
    movb    r0,(r1)+
    cmp    r1,$eline-1
    blo    2b
4:
    tst    (sp)+
    br    err1
2:
    mov    (sp)+,r3
    mov    r1,-(sp)
    sub    r3,r1
    movb    $'h,-(r3)
    clr    r0
    div    $10.,r0
    add    $'0,r1
    movb    r1,-(r3)
    mov    r0,r1
    clr    r0
    div    $10.,r0
    add    $'0,r1
    movb    r1,-(r3)
    add    $'0,r0
    movb    r0,-(r3)
    mov    (sp)+,r1
    clr    holquo
    br    1b
3:
    cmp    r0,$'h
    bne    2f
    clr    r3        / quote count
    mov    r1,-(sp)
3:
    cmp    r1,$line
    blos    4f
    movb    -(r1),r0
    cmpb    chrtab(r0),$4    / digit?
    beq    3b
    cmpb    chrtab(r0),$2    / test letter
    beq    3f
    cmp    r0,$'*
    beq    3f
    inc    r1
4:
    cmp    r1,(sp)
    bhis    4f
    movb    (r1)+,r0
    sub    $'0,r0
    mpy    $10.,r3
    add    r0,r3
    br    4b
4:
    mov    r3,r0
    beq    3f
    mov    r0,holquo
    mov    (sp)+,r1
    movb    $'h,(r1)+
4:
    jsr    pc,get
    cmp    r0,$'\n
    bne    5f
    mov    r0,ch
    mov    $' ,r0
5:
    bis    $200,r0
    movb    r0,(r1)+
    cmp    r1,$eline-1
    bhis    err1
    dec    holquo
    bne    4b
    br    1b
3:
    mov    (sp)+,r1
    mov    $'h,r0
2:
    movb    r0,(r1)+
    cmp    r1,$eline-1
    blo    1b
err1:
    jsr    r5,error; 1.
1:
    clrb    (r1)+
    mov    (sp)+,r3
    tstb    line
    bne    1f
    jmp    getline
1:
    rts    r5

isagn:
    jsr    r5,levzer; '=
        br 1f
    br    3f
1:
    mov    r0,-(sp)
    jsr    r5,levzer; ',
        br 4f
    jsr    r5,levzer; '(
        br 1f
    tst    (sp)+
2:
    rts    r5
1:
    cmp    (sp)+,r0
    blt    2b
    mov    r1,-(sp)
    mov    r0,r1
    inc    r1
    jsr    r5,levzer; ')
        br 1f
1:
    mov    (sp)+,r1
    cmpb    1(r0),$'=
    bne    3f
    rts    r5

levzer:
    mov    r1,r0
    clr    -(sp)
1:
    tst    (sp)
    bne    2f
    cmpb    (r0),(r5)
    beq    1f
2:
    cmpb    (r0),$'(
    bne    2f
    inc    (sp)
2:
    cmpb    (r0),$')
    bne    2f
    dec    (sp)
    blt    5f
2:
    tstb    (r0)+
    bne    1b
5:
    tst    (r5)+
1:
4:
    tst    (sp)+
3:
    tst    (r5)+
    rts    r5

get:
    movb    ch,r0
    beq    1f
    clrb    ch
    rts    pc
1:
    jsr    pc,get1
    cmp    r0,$'\n
    bne    2f
    jsr    pc,get1
    cmp    r0,$'&
    beq    1b
    movb    r0,ch1
    mov    $'\n,r0
2:
    tst    holquo
    bne    1f
    cmp    $' ,r0
    beq    1b
    cmp    $'\t,r0
    beq    1b
1:
    cmp    r0,$4        / test EOT
    bne    1f
    mov    $1,r0
    sys    write; mes; emes-mes
    mov    $1,r0        / syntax errors detected
    sys    exit
1:
    rts    pc

get1:
    movb    ch1,r0
    beq    1f
    clrb    ch1
    br    2f
1:
    jsr    r5,getc; ibuf
    bcs    1f
    bic    $!177,r0
    beq    1b
    cmp    r0,$'\n
    bne    2f
    inc    lino
2:
    tst    nlflg
    beq    2f
    clr    nlflg
    cmp    r0,$'c
    bne    2f
3:
    jsr    pc,get1
    cmp    r0,$'\n
    beq    1b
    cmp    r0,$4
    bne    3b
2:
    cmp    r0,$'\n
    bne    2f
    inc    nlflg
2:
    rts    pc
1:
    mov    $4,r0
    rts    pc

.data
nlflg:    1
.text
mes:
    <EOF on input\n\0>
emes:
.bss
lino:    .=.+2