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This commit is contained in:
Phil Budne 2016-03-01 15:18:17 -05:00
parent 6e38dad003
commit ed467cdb02
1 changed files with 120 additions and 117 deletions
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237
src/cmd/as.s
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@ -1,18 +1,18 @@
"** 05-1-4.pdf page 32
" as
jms init1 " initialize
jms init1 " initialize for pass 1
assm1:
lac eofflg
sza " saw EOF?
jmp assm2 " no.
lac passno
jmp assm2 " no.
lac passno " yes
sza " pass==0?
jmp finis " no, pass 2: done
jms init2 " pass 1: init for pass2
jms init2 " initialize for pass 2
assm2:
assm2: " main loop
jms gchar " get character
sad d4 " comma space or tab?
jmp assm1 " yes, ignore
@ -41,7 +41,7 @@ assm2:
assm3:
lac rand
sad d2
jmp assm4
jmp assm4 " yes
sza
jmp assm6
lac rator " fetch operator
@ -67,9 +67,9 @@ assm4:
lac rand+1
tad d4
dac lvrand
lac rator
sza
jmp assm5
lac rator " get operator
sza " ':'?
jmp assm5 " no
lac dot " load dot type
dac r " save as r type
lac dot+1 " get dot value
@ -171,13 +171,13 @@ finis:
sys close
-1
tad namsiz
cma
rcl
cma " get positive count of namelist entries
rcl " multiply by 6 to get words
dac char
rcl
tad char
dac 1f
lac o17
lac o17 " ?? creat mode bits??
sys creat; n.out " create "n.out"
dac bfi
sys write; namlst; 1: 0 " write name list
@ -197,16 +197,16 @@ process: 0
jmp proc4 " no, give "." error
sza " zero?
jmp proc1 " no
-1
tad cmflx+1 " '..' - 1
-1 " yes (".." type)
tad cmflx+1
cma
tad lvrand
tad lvrand " get "." - ".."
dac lvrand
proc1:
lac lvrand
spa
jmp proc4
spa " is relocated value positive?
jmp proc4 " no, give "." error
and o17700 " mask to block
sad bufadd " same block as buffer?
jmp proc2 " yes, same block
@ -224,25 +224,25 @@ proc1:
sys read; buf; 64
proc2:
lac lvrand
and o77 " get word within block
jms betwen; dm1; maxsto
dac maxsto
tad bufp
dac lvrand
lac r
sna
jmp proc3
sad d3
jmp proc5
lac lvrand " destination address
and o77 " word within block
jms betwen; dm1; maxsto " inside buffer?
dac maxsto " no, increment buffer size
tad bufp " add pointer to buffer
dac lvrand " save buffer pointer
lac r " get r type?
sna " non-zero ("." or label)?
jmp proc3 " no: zero (..)
sad d3 " three (user label)?
jmp proc5 " yes
lac cmflx+1 " get ".." value
tad r+1
tad r+1 " add to r value
dac r+1
proc3:
lac r+1
dac i lvrand
jmp i process
lac r+1 " get r value
dac i lvrand " save in buffer
jmp i process " return
proc4:
jms error; .>
@ -266,18 +266,18 @@ bufwr: 0 " write current buffer to a.out file
dac maxsto
jmp i bufwr
number: 0 " print decimal number?
dac 3f
number: 0 " print decimal number: append to buffer at index 8
dac 3f " save number
lac d1000
dac 2f
dac 2f " save divisor
1:
lac 3f
cll
idiv; 2: 0
dac 3f
lacq
tad o60
dac i 8
tad o60 " add ascii '0'
dac i 8 " save char
lac 2b
cll
idiv; 10
@ -288,17 +288,18 @@ number: 0 " print decimal number?
jmp i number
3: 0
" get character from buffer
" get character from buffer (two characters per word)
" call with:
" jms getsc; pointer_pointer
" where pointer_pointer contains a pointer to buffer
" where pointer_pointer refers to a pointer to buffer
" high bit in pointer indicates low char is next
getsc: 0
lac i getsc " get pointer pointer
dac sctalp " save
isz getsc " skip pointer pointer
lac i sctalp " fetch pointer
dac sctal " save
add o400000 " toggle high bit of pointer
add o400000 " toggle high bit, increment on wrap
dac i sctalp " save pointer back
ral " rotate high bit into link reg
lac i sctal " load word from buffer
@ -308,7 +309,7 @@ getsc: 0
jmp i getsc " return
" save characters: word after call is addr of pointer, -count pair
" high bit in pointer used to indicate high or low byte next?
" high bit in pointer used to indicate high/low
putsc: 0
and o177 " strip character to 7 bits
lmq " save in MQ
@ -318,7 +319,7 @@ putsc: 0
"** 05-1-4.pdf page 37
lac i sctalp " get pointer
dac sctal " save
add o400000 " toggle sign bit by adding -0
add o400000 " toggle pointer sign bit, increment on wrap
dac i sctalp " save pointer
sma cla " skip if minus & clear AC
jmp 1f " AC positive
@ -329,7 +330,7 @@ putsc: 0
1:
lac i sctal " load target word
omq " or in char from MQ
omq " or in low char from MQ
dac i sctal " save word back
lacq " restore character
jmp i putsc " return
@ -400,27 +401,27 @@ error: 0
jmp i error " return
1:
-1
tad mesp
dac 8
lac i error
dac i 8
lac o40
dac i 8
lac rator
sad d5
jmp 1f
lac savchr
sad o12
jmp 1f
lac lineno
tad mesp " get mes-1
dac 8 " save as index
lac i error " get error
dac i 8 " save in mess
lac o40 " get space
dac i 8 " save in mess
lac rator " get operator
sad d5 " word break (semi, newline)?
jmp 1f " yes
lac savchr " no, get saved char
sad o12 " newline?
jmp 1f " yes
lac lineno " get lineno
jmp 2f
1:
-1
tad lineno
tad lineno " get lineno -1
2:
jms number
lac o12
dac i 8
jms number " convert line number to ascii
lac o12 " get newline
dac i 8 " append to mess
-2
tad mesp
cma
@ -591,8 +592,8 @@ lqot: " left quote (<)
rqot: " right quote (>)
lac namc " get previous(?) char
1:
dac rand+1
lac d7
dac rand+1 " save value
lac d7 " return as literal
dac rator
jmp i gsymb
@ -770,20 +771,20 @@ lu2:
namep: name
gpair: 0
jms gsymb
jms gsymb " get a symbol
lac rator " get operator
sad d4 " space tab or comma?
jmp gpair+1 " yes, get another
jms betwen; dm1; d6 " anything but a digit?
jmp gp1 " no-- a digit
dzm rand
jms betwen; dm1; d6 " plus, minus, comma, semi?
jmp gp1 " no
dzm rand " clear "rand"
dzm rand+1
jmp i gpair
gp1: " here with digit
sad d7
lac d4
tad dm4
dac rand
jmp i gpair " return
gp1:
sad d7 " digit??
lac d4 " yes: switch to space??
tad dm4 " subtract 4??
dac rand " save as operand??
jms gsymb
lac rator
sad d4 " whitespace?
@ -867,13 +868,15 @@ grand: 0
dac rand+1
jmp i grand
" called with
" jms oper; argument
oper: 0
tad opsw
dac oper1
-1
tad i oper
dac 8
isz oper
tad i oper " pick up argument
dac 8 " store as index
isz oper " skip argument
lac r
sad d3
jmp oper2
@ -958,10 +961,10 @@ o77: 077
o74: 074
o76: 076
namsiz: -2
namlstp: namlst
fnamep: fakename
lactab: lac .+1 " character class table (8 unless noted)
namsiz: -2 " negative numberof namelist entries
namlstp: namlst " pointer to namelist
fnamep: fakename " pointer to fake namelist entry
lactab: lac .+1 " character (operator) class table (8 unless noted)
8;8;8;8;8;8;8;8
8;4;5;8;8;8;8;8 " TAB=4 NL=5
8;8;8;8;8;8;8;8
@ -979,44 +982,44 @@ lactab: lac .+1 " character class table (8 unless noted)
6;6;6;6;6;6;6;6
6;6;6;8;8;8;8;8
fbflg: .=.+1
tal: .=.+1
talc: .=.+1
tal1: .=.+1
tal1c: .=.+1
narg: .=.+1
lvrand: .=.+1
eofflg: .=.+1
namc: .=.+1
passno: .=.+1
char: .=.+1
savchr: .=.+1
comflg: .=.+1
rator: .=.+1
orator: .=.+1
rand: .=.+2
srand: .=.+2
r: .=.+2
name: .=.+4
buf: .=.+64
iobuf: .=.+64
fbx: .=.+10 " forward/backward pointers?
mes: .=.+20
iof: .=.+1
bfi: .=.+1
bfo: .=.+1
lineno: .=.+1
fbflg: .=.+1 " f/b label flag
tal: .=.+1 " iobuf pointer
talc: .=.+1 " -bytecount-1
tal1: .=.+1 " namebuf pointer
tal1c: .=.+1 " -bytecount-1
narg: .=.+1 " argc
lvrand: .=.+1 " numeric constant, word address
eofflg: .=.+1 " 0 on EOF??
namc: .=.+1 " saved char, temporary
passno: .=.+1 " 0=pass1, 1=pass2
char: .=.+1 " current character
savchr: .=.+1 " pushed back char
comflg: .=.+1 " comment flag
rator: .=.+1 " (opo)rator (char type)
orator: .=.+1 " ?? (op)orator
rand: .=.+2 " ?? (ope)rand (type/address pair)
srand: .=.+2 " ?? another operand
r: .=.+2 " ?? yet another??
name: .=.+4 " buffer for accumulating names
buf: .=.+64 " a.out output buffer
iobuf: .=.+64 " input buffer
fbx: .=.+10 " forward/backward counters
mes: .=.+20 " (error) message buffer
iof: .=.+1 " source file fd
bfi: .=.+1 " a.out input fd
bfo: .=.+1 " a.out output fd
lineno: .=.+1 " source file line number
fakename: .=.+6 " dummy entry returned by tlookup??
namlst:
.=.+4
dot: " dot type, value
.=.+6
cmflx: " dotdot type, value
" first four words of name list are symbol (space padded)
fakename: .=.+6 " dummy namelist entry returned by tlookup??
namlst: " symbol table
.=.+4 " dot name
dot: " dot type, value
.=.+6 " dot dot name
cmflx: " dotdot type, value
" namelist (symbol table) entries are 6 words.
" four words of symbol (space padded) name
" next word is type??
" 0: initial dotdot type
" 1: initial dot type
" 3: set by "lookup"
" last word is value??
" 1: initial dot type (reset on error)
" 3: set by "lookup" (user symbol)
" last word is value??