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/ a3 -- pdp-11 assembler pass 2

assem:
       jsr     pc,readop
       cmp     r4,$5
       beq     2f
       cmp     r4,$'<
       beq     2f
       jsr     pc,checkeos
               br eal1
       mov     r4,-(sp)
       cmp     (sp),$1
       bne     1f
       mov     $2,(sp)
       jsr     pc,getw
       mov     r4,numval
1:
       jsr     pc,readop
       cmp     r4,$'=
       beq     4f
       cmp     r4,$':
       beq     1f
       mov     r4,savop
       mov     (sp)+,r4
2:
       jsr     pc,opline
dotmax:
       tstb    passno
       bne     eal1
       movb    dotrel,r0
       asl     r0
       cmp     dot,txtsiz-4(r0)
       blos    ealoop
       mov     dot,txtsiz-4(r0)
eal1:
       jmp     ealoop
1:
       mov     (sp)+,r4
       cmp     r4,$200
       bhis    1f
       cmp     r4,$2
       beq     3f
       jsr     r5,error; 'x
       br      assem
1:
       tstb    passno
       bne     2f
       movb    (r4),r0
       bic     $!37,r0
       beq     5f
       cmp     r0,$33
       blt     6f
       cmp     r0,$34
       ble     5f
6:
       jsr     r5,error; 'm
5:
       bic     $37,(r4)
       bis     dotrel,(r4)
       mov     2(r4),brdelt
       sub     dot,brdelt
       mov     dot,2(r4)
       br      assem
2:
       cmp     dot,2(r4)
       beq     assem
       jsr     r5,error; 'p
       br      assem
3:
       mov     numval,r4
       jsr     pc,fbadv
       asl     r4
       mov     curfb(r4),r0
       movb    dotrel,(r0)
       mov     2(r0),brdelt
       sub     dot,brdelt
       mov     dot,2(r0)
       br      assem
4:
       jsr     pc,readop
       jsr     pc,expres
       mov     (sp)+,r1
       cmp     r1,$symtab      /test for dot
       bne     1f
       bic     $40,r3
       cmp     r3,dotrel       / can't change relocation
       bne     2f
       cmp     r3,$4           / bss
       bne     3f
       mov     r2,dot
       br      dotmax
3:
       sub     dot,r2
       bmi     2f
       mov     r2,-(sp)
3:
       dec     (sp)
       bmi     3f
       clr     r2
       mov     $1,r3
       jsr     pc,outb
       br      3b
3:
       tst     (sp)+
       br      dotmax
2:
       jsr     r5,error; '.
       br      ealoop
1:
       cmp     r3,$40
       bne     1f
       jsr     r5,error; 'r
1:
       bic     $37,(r1)
       bic     $!37,r3
       bne     1f
       clr     r2
1:
       bisb    r3,(r1)
       mov     r2,2(r1)

ealoop:
       cmp     r4,$'\n
       beq     1f
       cmp     r4,$'\e
       bne     9f
       rts     pc
1:
       inc     line
9:
       jmp     assem

checkeos:
       cmp     r4,$'\n
       beq     1f
       cmp     r4,$';
       beq     1f
       cmp     r4,$'\e
       beq     1f
       add     $2,(sp)
1:
       rts     pc

fbadv:
       asl     r4
       mov     nxtfb(r4),r1
       mov     r1,curfb(r4)
       bne     1f
       mov     fbbufp,r1
       br      2f
1:
       add     $4,r1
2:
       cmpb    1(r1),r4
       beq     1f
       tst     (r1)
       bpl     1b
1:
       mov     r1,nxtfb(r4)
       asr     r4
       rts     pc