Research V5 development

Work on file usr/source/s1/as23.s

Synthesized-from: v5

diff --git a/usr/source/s1/as23.s b/usr/source/s1/as23.s
new file mode 100644 (file)
index 0000000..11e7215
--- /dev/null
+++ b/usr/source/s1/as23.s
@@ -0,0 +1,166 @@
+/
+/ copyright 1972 bell telephone laboratories inc.
+/
+
+/ 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
+