--- gforth/prims2x.fs	2003/03/22 10:04:07	1.135
+++ gforth/prims2x.fs	2007/12/31 17:34:58	1.168
@@ -1,6 +1,6 @@
 \ converts primitives to, e.g., C code 
 
-\ Copyright (C) 1995,1996,1997,1998,2000,2003 Free Software Foundation, Inc.
+\ Copyright (C) 1995,1996,1997,1998,2000,2003,2004,2005,2006,2007 Free Software Foundation, Inc.
 
 \ This file is part of Gforth.
 
@@ -51,8 +51,22 @@
 \ (stack-in-index-xt and a test for stack==instruction-stream); there
 \ should be only one.
 
+
+\ for backwards compatibility, jaw
+require compat/strcomp.fs
+
+[undefined] outfile-execute [if]
+    : outfile-execute ( ... xt file-id -- ... )
+	\ unsafe replacement
+	outfile-id >r to outfile-id execute r> to outfile-id ;
+[then]
+
 warnings off
 
+\ redefinitions of kernel words not present in gforth-0.6.1
+: latestxt lastcfa @ ;
+: latest last @ ;
+
 [IFUNDEF] try
 include startup.fs
 [THEN]
@@ -95,6 +109,9 @@ variable include-skipped-insts
 \ inline arguments (false)
 include-skipped-insts off
 
+2variable threaded-code-pointer-type \ type used for geninst etc.
+s" Inst **" threaded-code-pointer-type 2!
+
 variable immarg \ values for immediate arguments (to be used in IMM_ARG macros)
 $12340000 immarg !
 
@@ -127,15 +144,13 @@ $12340000 immarg !
     over - type cr
     line-start @ rawinput @ over - typewhite ." ^" cr ;
 
+: print-error { addr u -- }
+    filename 2@ type ." :" line @ 0 .r ." : " addr u type cr
+    print-error-line ;
+
 : ?print-error { f addr u -- }
     f ?not? if
-	outfile-id >r try
-	    stderr to outfile-id
-	    filename 2@ type ." :" line @ 0 .r ." : " addr u type cr
-	    print-error-line
-	    0
-	recover endtry
-	r> to outfile-id throw
+	addr u ['] print-error stderr outfile-execute
 	1 (bye) \ abort
     endif ;
 
@@ -181,8 +196,30 @@ struct%
     cell%    field type-store \ xt of store code generator ( item -- )
 end-struct type%
 
+struct%
+    cell%    field register-number
+    cell%    field register-type \ pointer to type
+    cell% 2* field register-name \ c name
+end-struct register%
+
+struct%
+    cell% 2* field ss-registers  \ addr u; ss-registers[0] is TOS
+                                 \ 0 means: use memory
+    cell%    field ss-offset     \ stack pointer offset: sp[-offset] is TOS
+end-struct ss% \ stack-state
+
+struct%
+    cell%              field state-enabled
+    cell%              field state-number
+    cell% max-stacks * field state-sss
+end-struct state%
+
 variable next-stack-number 0 next-stack-number !
 create stacks max-stacks cells allot \ array of stacks
+256 constant max-registers
+create registers max-registers cells allot \ array of registers
+variable nregisters 0 nregisters ! \ number of registers
+variable next-state-number 0 next-state-number ! \ next state number
 
 : stack-in-index ( in-size item -- in-index )
     item-offset @ - 1- ;
@@ -203,13 +240,13 @@ create stacks max-stacks cells allot \ a
     rdrop ;
 
 : map-stacks { xt -- }
-    \ perform xt for all stacks
+    \ perform xt ( stack -- ) for all stacks
     next-stack-number @ 0 +do
 	stacks i th @ xt execute
     loop ;
 
 : map-stacks1 { xt -- }
-    \ perform xt for all stacks except inst-stream
+    \ perform xt ( stack -- ) for all stacks except inst-stream
     next-stack-number @ 1 +do
 	stacks i th @ xt execute
     loop ;
@@ -218,7 +255,7 @@ create stacks max-stacks cells allot \ a
 
 : init-item ( addr u addr1 -- )
     \ initialize item at addr1 with name addr u
-    \ !! remove stack prefix
+    \ the stack prefix is removed by the stack-prefix
     dup item% %size erase
     item-name 2! ;
 
@@ -239,6 +276,7 @@ struct%
     cell% 2* field prim-name
     cell% 2* field prim-wordset
     cell% 2* field prim-c-name
+    cell% 2* field prim-c-name-orig \ for reprocessed prims, the original name
     cell% 2* field prim-doc
     cell% 2* field prim-c-code
     cell% 2* field prim-forth-code
@@ -251,6 +289,7 @@ struct%
     cell%    field prim-effect-out-end
     cell% max-stacks * field prim-stacks-in  \ number of in items per stack
     cell% max-stacks * field prim-stacks-out \ number of out items per stack
+    cell% max-stacks * field prim-stacks-sync \ sync flag per stack
 end-struct prim%
 
 : make-prim ( -- prim )
@@ -262,6 +301,9 @@ end-struct prim%
 0 value combined \ in combined prims the combined prim
 variable in-part \ true if processing a part
  in-part off
+0 value state-in  \ state on entering prim
+0 value state-out \ state on exiting prim
+0 value state-default  \ canonical state at bb boundaries
 
 : prim-context ( ... p xt -- ... )
     \ execute xt with prim set to p
@@ -271,6 +313,9 @@ variable in-part \ true if processing a
     r> to prim
     throw ;
 
+: prim-c-name-2! ( c-addr u -- )
+    2dup prim prim-c-name 2! prim prim-c-name-orig 2! ;
+
 1000 constant max-combined
 create combined-prims max-combined cells allot
 variable num-combined
@@ -315,6 +360,9 @@ wordlist constant primitives
     \ address of number of stack items in effect out
     stack-number @ cells prim prim-stacks-out + ;
 
+: stack-prim-stacks-sync ( stack -- addr )
+    prim prim-stacks-sync swap stack-number @ th ;
+
 \ global vars
 variable c-line
 2variable c-filename
@@ -322,6 +370,13 @@ variable name-line
 2variable name-filename
 2variable last-name-filename
 Variable function-number 0 function-number !
+Variable function-old 0 function-old !
+: function-diff ( -- )
+    ." GROUPADD(" function-number @ function-old @ - 0 .r ." )" cr
+    function-number @ function-old ! ;
+: forth-fdiff ( -- )
+    function-number @ function-old @ - 0 .r ."  groupadd" cr
+    function-number @ function-old ! ;
 
 \ a few more set ops
 
@@ -337,18 +392,36 @@ defer inst-stream-f ( -- stack )
 \ stack access stuff
 
 : normal-stack-access0 { n stack -- }
+    \ n has the ss-offset already applied (see ...-access1)
     n stack stack-access-transform @ execute ." [" 0 .r ." ]" ;
-    
-: normal-stack-access1 { n stack -- }
-    stack stack-pointer 2@ type
-    n if
-	n stack normal-stack-access0
+
+: state-ss { stack state -- ss }
+    state state-sss stack stack-number @ th @ ;
+
+: stack-reg { n stack state -- reg }
+    \ n is the index (TOS=0); reg is 0 if the access is to memory
+    stack state state-ss ss-registers 2@ n u> if ( addr ) \ in ss-registers?
+	n th @
     else
-	." TOS"
+	drop 0
     endif ;
 
-: normal-stack-access ( n stack -- )
-    dup inst-stream-f = if
+: .reg ( reg -- )
+    register-name 2@ type ;
+
+: stack-offset ( stack state -- n )
+    \ offset for stack in state
+    state-ss ss-offset @ ;
+
+: normal-stack-access1 { n stack state -- }
+    n stack state stack-reg ?dup-if
+	.reg exit
+    endif
+    stack stack-pointer 2@ type
+    n stack state stack-offset - stack normal-stack-access0 ;
+
+: normal-stack-access ( n stack state -- )
+    over inst-stream-f = if
 	." IMM_ARG(" normal-stack-access1 ." ," immarg ? ." )"
 	1 immarg +!
     else
@@ -377,7 +450,7 @@ defer inst-stream-f ( -- stack )
     stack stack-number @ part-num @ s-c-max-depth @
 \    max-depth stack stack-number @ th @ ( ndepth nmaxdepth )
     over <= if ( ndepth ) \ load from memory
-	stack normal-stack-access
+	stack state-in normal-stack-access
     else
 	drop n stack part-stack-access
     endif ;
@@ -391,7 +464,7 @@ defer inst-stream-f ( -- stack )
     stack stack-number @ part-num @ s-c-max-back-depth @
     over <= if ( ndepth )
 	stack combined ['] stack-diff prim-context -
-	stack normal-stack-access
+	stack state-out normal-stack-access
     else
 	drop n stack part-stack-access
     endif ;
@@ -401,7 +474,7 @@ defer inst-stream-f ( -- stack )
     in-part @ if
 	part-stack-read
     else
-	normal-stack-access
+	state-in normal-stack-access
     endif ;
 
 : stack-write ( n stack -- )
@@ -409,7 +482,7 @@ defer inst-stream-f ( -- stack )
     in-part @ if
 	part-stack-write
     else
-	normal-stack-access
+	state-out normal-stack-access
     endif ;
 
 : item-in-index { item -- n }
@@ -436,31 +509,34 @@ defer inst-stream-f ( -- stack )
     ." vm_two"
     r@ item-stack-type-name type ." 2"
     r@ item-type @ print-type-prefix ." ("
-    r@ item-in-index r@ item-stack @ 2dup ." (Cell)" stack-read
-    ." , "                      -1 under+ ." (Cell)" stack-read
+    r@ item-in-index r@ item-stack @ 2dup stack-read
+    ." , "                      -1 under+ stack-read
     ." , " r@ item-name 2@ type
     ." )" cr
     rdrop ;
 
 : same-as-in? ( item -- f )
- \ f is true iff the offset and stack of item is the same as on input
- >r
- r@ item-first @ if
-     rdrop false exit
- endif
- r@ item-name 2@ prim prim-items-wordlist @ search-wordlist 0= abort" bug"
- execute @
- dup r@ =
- if \ item first appeared in output
-   drop false
- else
-   dup  item-stack  @ r@ item-stack  @ = 
-   swap item-offset @ r@ item-offset @ = and
- endif
- rdrop ;
+    \ f is true iff the offset and stack of item is the same as on input
+    >r
+    r@ item-stack @ stack-prim-stacks-sync @ if
+	rdrop false exit
+    endif
+    r@ item-first @ if
+	rdrop false exit
+    endif
+    r@ item-name 2@ prim prim-items-wordlist @ search-wordlist 0= abort" bug"
+    execute @
+    dup r@ =
+    if \ item first appeared in output
+	drop false
+    else
+	dup  item-stack  @ r@ item-stack  @ = 
+	swap item-offset @ r@ item-offset @ = and
+    endif
+    rdrop ;
 
 : item-out-index ( item -- n )
-    \ n is the index of item (in the in-effect)
+    \ n is the index of item (in the out-effect)
     >r r@ item-stack @ stack-out @ r> item-offset @ - 1- ;
 
 : really-store-single ( item -- )
@@ -472,17 +548,14 @@ defer inst-stream-f ( -- stack )
     r@ item-out-index r@ item-stack @ stack-write ." );"
     rdrop ;
 
-: store-single ( item -- )
-    >r
-    store-optimization @ in-part @ 0= and r@ same-as-in? and if
-	r@ item-in-index 0= r@ item-out-index 0= xor if
-	    ." IF_" r@ item-stack @ stack-pointer 2@ type
-	    ." TOS(" r@ really-store-single ." );" cr
-	endif
-    else
-	r@ really-store-single cr
-    endif
-    rdrop ;
+: store-single { item -- }
+    item item-stack @ { stack }
+    store-optimization @ in-part @ 0= and item same-as-in? and
+    item item-in-index  stack state-in  stack-reg       \  in reg/mem
+    item item-out-index stack state-out stack-reg = and \ out reg/mem
+    0= if
+	item really-store-single cr
+    endif ;
 
 : store-double ( item -- )
 \ !! store optimization is not performed, because it is not yet needed
@@ -558,7 +631,8 @@ does> ( item -- )
 	    UNLOOP EXIT
 	endif
 	-1 s+loop
-    \ we did not find a type, abort
+	\ we did not find a type, abort
+	abort
     false s" unknown prefix" ?print-error ;
 
 : declaration ( item -- )
@@ -592,6 +666,38 @@ does> ( item -- )
     stack item item-stack !
     item declaration ;
 
+: set-prim-stacks-sync ( stack -- )
+    stack-prim-stacks-sync on ;
+
+: clear-prim-stacks-sync ( stack -- )
+    stack-prim-stacks-sync off ;
+
+
+get-current prefixes set-current
+: ... ( item -- )
+    \ this "prefix" ensures that the appropriate stack is synced with memory
+    dup item-name 2@ s" ..." str= 0= abort" '...' must end the item name"
+    item-stack @ dup if
+	set-prim-stacks-sync
+    else \ prefixless "..." syncs all stacks
+	drop ['] set-prim-stacks-sync map-stacks1
+    endif ;
+set-current
+
+create ...-item ( -- addr ) \ just used for letting stack-prefixes work on it
+item% %allot drop           \ stores the stack temporarily until used by ...
+
+: init-item1 ( addr1 addr u -- addr2 )
+    \ initialize item at addr1 with name addr u, next item is at addr2
+    \ !! make sure that any mention of "..." is only stack-prefixed
+    2dup s" ..." search nip nip if ( addr1 addr u )
+	0 ...-item item-stack ! \ initialize to prefixless
+	2dup ...-item item-name 2!
+	...-item rot rot execute-prefix ( addr1 )
+    else
+	2 pick init-item item% %size +
+    endif ;
+
 \ types pointed to by stacks for use in combined prims
 \ !! output-c-combined shouldn't use these names!
 : stack-type-name ( addr u "name" -- )
@@ -600,21 +706,78 @@ does> ( item -- )
 wordlist constant type-names \ this is here just to meet the requirement
                     \ that a type be a word; it is never used for lookup
 
+: define-type ( addr u -- xt )
+    \ define single type with name addr u, without stack
+    get-current type-names set-current >r
+    2dup nextname stack-type-name
+    r> set-current
+    latestxt ;
+
 : stack ( "name" "stack-pointer" "type" -- )
     \ define stack
     name { d: stack-name }
     name { d: stack-pointer }
     name { d: stack-type }
-    get-current type-names set-current
-    stack-type 2dup nextname stack-type-name
-    set-current
-    stack-pointer latestxt >body stack-name nextname make-stack ;
+    stack-type define-type
+    stack-pointer rot >body stack-name nextname make-stack ;
 
 stack inst-stream IP Cell
 ' inst-in-index inst-stream stack-in-index-xt !
 ' inst-stream <is> inst-stream-f
 \ !! initialize stack-in and stack-out
 
+\ registers
+
+: make-register ( type addr u -- )
+    \ define register with type TYPE and name ADDR U.
+    nregisters @ max-registers < s" too many registers" ?print-error
+    2dup nextname create register% %allot >r
+    r@ register-name 2!
+    r@ register-type !
+    nregisters @ r@ register-number !
+    1 nregisters +!
+    rdrop ;
+
+: register ( "name" "type" -- )
+    \ define register
+    name { d: reg-name }
+    name { d: reg-type }
+    reg-type define-type >body
+    reg-name make-register ;
+
+\ stack-states
+
+: stack-state ( a-addr u uoffset "name" -- )
+    create ss% %allot >r
+    r@ ss-offset !
+    r@ ss-registers 2!
+    rdrop ;
+
+0 0 0 stack-state default-ss
+
+\ state
+
+: state ( "name" -- )
+    \ create a state initialized with default-sss
+    create state% %allot { s }
+    s state-enabled on
+    next-state-number @ s state-number ! 1 next-state-number +!
+    max-stacks 0 ?do
+	default-ss s state-sss i th !
+    loop ;
+
+: state-disable ( state -- )
+    state-enabled off ;
+
+: state-enabled? ( state -- f )
+    state-enabled @ ;
+
+: .state ( state -- )
+    0 >body - >name .name ;
+
+: set-ss ( ss stack state -- )
+    state-sss swap stack-number @ th ! ;
+
 \ offset computation
 \ the leftmost (i.e. deepest) item has offset 0
 \ the rightmost item has the highest offset
@@ -638,32 +801,68 @@ stack inst-stream IP Cell
     prim prim-effect-out prim prim-effect-out-end @ ['] compute-offset-out map-items
     inst-stream stack-out @ 0= s" # can only be on the input side" ?print-error ;
 
+: init-simple { prim -- }
+    \ much of the initialization is elsewhere
+    ['] clear-prim-stacks-sync map-stacks ;
+
 : process-simple ( -- )
     prim prim { W^ key } key cell
     combinations ['] constant insert-wordlist
     declarations compute-offsets
     output @ execute ;
 
-: flush-a-tos { stack -- }
-    stack stack-out @ 0<> stack stack-in @ 0= and
-    if
-	." IF_" stack stack-pointer 2@ 2dup type ." TOS("
-	2dup type 0 stack normal-stack-access0 ."  = " type ." TOS);" cr
-    endif ;
+: stack-state-items ( stack state -- n )
+    state-ss ss-registers 2@ nip ;
 
-: flush-tos ( -- )
-    ['] flush-a-tos map-stacks1 ;
+: unused-stack-items { stack -- n-in n-out }
+    \ n-in  are the stack items in state-in  not used    by prim
+    \ n-out are the stack items in state-out not written by prim
+    stack state-in  stack-state-items stack stack-in  @ - 0 max
+    stack state-out stack-state-items stack stack-out @ - 0 max ;
+
+: spill-stack-items { stack -- u }
+    \ there are u items to spill in stack
+    stack unused-stack-items
+    stack stack-prim-stacks-sync @ if
+	drop 0
+    endif
+    swap - ;
 
-: fill-a-tos { stack -- }
-    stack stack-out @ 0= stack stack-in @ 0<> and
-    if
-	." IF_" stack stack-pointer 2@ 2dup type ." TOS("
-	2dup type ." TOS = " type 0 stack normal-stack-access0 ." );" cr
-    endif ;
+: spill-stack { stack -- }
+    \ spill regs of state-in that are not used by prim and are not in state-out
+    stack state-in stack-offset { offset }
+    stack state-in stack-state-items ( items )
+    dup stack spill-stack-items + +do
+	\ loop through the bottom items
+	stack stack-pointer 2@ type
+	i offset - stack normal-stack-access0 ."  = "
+	i stack state-in normal-stack-access1 ." ;" cr
+    loop ;
+
+: spill-state ( -- )
+    ['] spill-stack map-stacks1 ;
+
+: fill-stack-items { stack -- u }
+    \ there are u items to fill in stack
+    stack unused-stack-items
+    stack stack-prim-stacks-sync @ if
+	swap drop 0 swap
+    endif
+    - ;
+
+: fill-stack { stack -- }
+    stack state-out stack-offset { offset }
+    stack state-out stack-state-items ( items )
+    dup stack fill-stack-items + +do
+	\ loop through the bottom items
+	i stack state-out normal-stack-access1 ."  = "
+	stack stack-pointer 2@ type
+	i offset - stack normal-stack-access0 ." ;" cr
+    loop ;
 
-: fill-tos ( -- )
+: fill-state ( -- )
     \ !! inst-stream for prefetching?
-    ['] fill-a-tos map-stacks1 ;
+    ['] fill-stack map-stacks1 ;
 
 : fetch ( addr -- )
     dup item-type @ type-fetch @ execute ;
@@ -671,27 +870,84 @@ stack inst-stream IP Cell
 : fetches ( -- )
     prim prim-effect-in prim prim-effect-in-end @ ['] fetch map-items ;
 
+: reg-reg-move ( reg-from reg-to -- )
+    2dup = if
+	2drop
+    else
+	.reg ."  = " .reg ." ;" cr
+    endif ;
+
+: stack-bottom-reg { n stack state -- reg }
+    stack state stack-state-items n - 1- stack state stack-reg ;
+
+: stack-moves { stack -- }
+    \ generate moves between registers in state-in/state-out that are
+    \ not spilled or consumed/produced by prim.
+    \ !! this works only for a simple stack cache, not e.g., for
+    \ rotating stack caches, or registers shared between stacks (the
+    \ latter would also require a change in interface)
+    \ !! maybe place this after NEXT_P1?
+    stack unused-stack-items 2dup < if ( n-in n-out )
+	\ move registers from 0..n_in-1 to n_out-n_in..n_out-1
+	over - { diff } ( n-in )
+	-1 swap 1- -do
+	    i stack state-in stack-bottom-reg ( reg-from )
+	    i diff + stack state-out stack-bottom-reg reg-reg-move
+	1 -loop
+    else
+	\ move registers from n_in-n_out..n_in-1 to 0..n_out-1
+	swap over - { diff } ( n-out )
+	0 +do
+	    i diff + stack state-in stack-bottom-reg ( reg-from )
+	    i stack state-out stack-bottom-reg reg-reg-move
+	loop
+    endif ;
+
 : stack-update-transform ( n1 stack -- n2 )
     \ n2 is the number by which the stack pointer should be
     \ incremented to pop n1 items
     stack-access-transform @ dup >r execute
     0 r> execute - ;
 
-: stack-pointer-update { stack -- }
-    \ stacks grow downwards
-    stack stack-diff
-    ?dup-if \ this check is not necessary, gcc would do this for us
+: update-stack-pointer { stack n -- }
+    n if \ this check is not necessary, gcc would do this for us
 	stack inst-stream = if
-	    ." INC_IP(" 0 .r ." );" cr
+	    ." INC_IP(" n 0 .r ." );" cr
 	else
 	    stack stack-pointer 2@ type ."  += "
-	    stack stack-update-transform 0 .r ." ;" cr
+	    n stack stack-update-transform 0 .r ." ;" cr
 	endif
     endif ;
 
+: stack-pointer-update { stack -- }
+    \ and moves
+    \ stacks grow downwards
+    stack stack-prim-stacks-sync @ if
+	stack stack-in @
+	stack state-in  stack-offset -
+	stack swap update-stack-pointer
+    else
+	stack stack-diff ( in-out )
+	stack state-in  stack-offset -
+	stack state-out stack-offset + ( [in-in_offset]-[out-out_offset] )
+	stack swap update-stack-pointer
+	stack stack-moves
+    endif ;
+
 : stack-pointer-updates ( -- )
     ['] stack-pointer-update map-stacks ;
 
+: stack-pointer-update2 { stack -- }
+    stack stack-prim-stacks-sync @ if
+	stack state-out stack-offset
+	stack stack-out @ -
+	stack swap update-stack-pointer
+    endif ;
+
+: stack-pointer-updates2 ( -- )
+    \ update stack pointers after C code, where necessary
+    ['] stack-pointer-update2 map-stacks ;
+
 : store ( item -- )
 \ f is true if the item should be stored
 \ f is false if the store is probably not necessary
@@ -734,6 +990,17 @@ stack inst-stream IP Cell
     endif
     2drop ;
 
+
+defer output-nextp0
+:noname ( -- )
+    ." NEXT_P0;" cr ;
+is output-nextp0
+
+defer output-nextp1
+:noname ( -- )
+    ." NEXT_P1;" cr ;
+is output-nextp1
+
 : output-nextp2 ( -- )
     ." NEXT_P2;" cr ;
 
@@ -742,29 +1009,46 @@ variable tail-nextp2 \ xt to execute for
 
 : output-label2 ( -- )
     ." LABEL2(" prim prim-c-name 2@ type ." )" cr
-    ." NEXT_P2;" cr ;
+    ." NEXT_P1_5;" cr
+    ." LABEL3(" prim prim-c-name 2@ type ." )" cr
+    ." DO_GOTO;" cr ;
 
 : output-c-tail1 { xt -- }
     \ the final part of the generated C code, with xt printing LABEL2 or not.
     output-super-end
     print-debug-results
-    ." NEXT_P1;" cr
+    output-nextp1
+    stack-pointer-updates2
     stores
-    fill-tos 
+    fill-state 
     xt execute ;
 
+: output-c-vm-jump-tail ( -- )
+    \ !! this functionality not yet implemented for superinstructions
+    output-super-end
+    print-debug-results
+    stores
+    fill-state 
+    ." LABEL2(" prim prim-c-name 2@ type ." )" cr
+    ." LABEL3(" prim prim-c-name 2@ type ." )" cr
+    ." DO_GOTO;" cr ;
+
 : output-c-tail1-no-stores { xt -- }
     \ the final part of the generated C code for combinations
     output-super-end
-    ." NEXT_P1;" cr
-    fill-tos 
+    output-nextp1
+    fill-state 
     xt execute ;
 
 : output-c-tail ( -- )
     tail-nextp2 @ output-c-tail1 ;
 
 : output-c-tail2 ( -- )
-    ['] output-label2 output-c-tail1 ;
+    prim prim-c-code 2@ s" VM_JUMP(" search nip nip if
+	output-c-vm-jump-tail
+    else
+	['] output-label2 output-c-tail1
+    endif ;
 
 : output-c-tail-no-stores ( -- )
     tail-nextp2 @ output-c-tail1-no-stores ;
@@ -791,16 +1075,24 @@ variable tail-nextp2 \ xt to execute for
 
 : print-entry ( -- )
     ." LABEL(" prim prim-c-name 2@ type ." )" ;
-    
-: output-c ( -- ) 
-    print-entry ."  /* " prim prim-name 2@ type ."  ( " prim prim-stack-string 2@ type ." ) */" cr
+
+: prim-type ( addr u -- )
+    \ print out a primitive, but avoid "*/"
+    2dup s" */" search  nip nip  IF
+	bounds ?DO  I c@ dup '* = IF  drop 'x  THEN  emit  LOOP
+    ELSE  type  THEN ;
+
+: output-c ( -- )
+    print-entry ."  /* " prim prim-name 2@ prim-type
+    ."  ( " prim prim-stack-string 2@ type ." ) "
+    state-in .state ." -- " state-out .state ."  */" cr
     ." /* " prim prim-doc 2@ type ."  */" cr
     ." NAME(" quote prim prim-name 2@ type quote ." )" cr \ debugging
     ." {" cr
     ." DEF_CA" cr
     print-declarations
-    ." NEXT_P0;" cr
-    flush-tos
+    output-nextp0
+    spill-state
     fetches
     print-debug-args
     stack-pointer-updates
@@ -862,12 +1154,16 @@ variable tail-nextp2 \ xt to execute for
     endif
     ." }" cr ;
 
+: prim-branch? { prim -- f }
+    \ true if prim is a branch or super-end
+    prim prim-c-code 2@  s" SET_IP" search nip nip 0<> ;
+
 : output-superend ( -- )
     \ output flag specifying whether the current word ends a dynamic superinst
-    prim prim-c-code 2@  s" SET_IP"    search nip nip
-    prim prim-c-code 2@  s" SUPER_END" search nip nip or 0<>
+    prim prim-branch?
+    prim prim-c-code 2@  s" SUPER_END" search nip nip 0<> or
     prim prim-c-code 2@  s" SUPER_CONTINUE" search nip nip 0= and
-    negate 0 .r ." , /* " prim prim-name 2@ type ."  */" cr ;
+    negate 0 .r ." , /* " prim prim-name 2@ prim-type ."  */" cr ;
 
 : gen-arg-parm { item -- }
     item item-stack @ inst-stream = if
@@ -889,9 +1185,10 @@ variable tail-nextp2 \ xt to execute for
 
 : output-gen ( -- )
     \ generate C code for generating VM instructions
-    ." void gen_" prim prim-c-name 2@ type ." (Inst **ctp" gen-args-parm ." )" cr
+    ." void gen_" prim prim-c-name 2@ type ." ("
+    threaded-code-pointer-type 2@ type ." ctp" gen-args-parm ." )" cr
     ." {" cr
-    ."   gen_inst(ctp, vm_prim[" function-number @ 0 .r ." ]);" cr
+    ."   gen_inst(ctp, " function-number @ 0 .r ." );" cr
     gen-args-gen
     ." }" cr ;
 
@@ -918,7 +1215,7 @@ variable tail-nextp2 \ xt to execute for
 \      data-stack   stack-used? IF ." Cell *sp=SP;" cr THEN
 \      fp-stack     stack-used? IF ." Cell *fp=*FP;" cr THEN
 \      return-stack stack-used? IF ." Cell *rp=*RP;" cr THEN
-\      flush-tos
+\      spill-state
 \      fetches
 \      stack-pointer-updates
 \      fp-stack   stack-used? IF ." *FP=fp;" cr THEN
@@ -927,7 +1224,7 @@ variable tail-nextp2 \ xt to execute for
 \      prim prim-c-code 2@ type
 \      ." }" cr
 \      stores
-\      fill-tos
+\      fill-state
 \      ." return (sp);" cr
 \      ." }" cr
 \      cr ;
@@ -938,8 +1235,11 @@ variable tail-nextp2 \ xt to execute for
 : output-alias ( -- ) 
     ( primitive-number @ . ." alias " ) ." Primitive " prim prim-name 2@ type cr ;
 
-: output-c-prim-num ( -- )
-    ." #define N_" prim prim-c-name 2@ type prim prim-num @ 8 + 4 .r cr ;
+defer output-c-prim-num ( -- )
+
+:noname ( -- )
+    ." N_" prim prim-c-name 2@ type ." ," cr ;
+is output-c-prim-num
 
 : output-forth ( -- )  
     prim prim-forth-code @ 0=
@@ -1154,12 +1454,92 @@ variable tail-nextp2 \ xt to execute for
     compute-max-back-depths
     output-combined perform ;
 
+\ reprocessing (typically to generate versions for another cache states)
+\ !! use prim-context
+
+variable reprocessed-num 0 reprocessed-num !
+
+: new-name ( -- c-addr u )
+    reprocessed-num @ 0
+    1 reprocessed-num +!
+    <# #s 'p hold '_ hold #> save-mem ;
+
+: reprocess-simple ( prim -- )
+    to prim
+    new-name prim prim-c-name 2!
+    output @ execute ;
+
+: lookup-prim ( c-addr u -- prim )
+    primitives search-wordlist 0= -13 and throw execute ;
+
+: state-prim1 { in-state out-state prim -- }
+    in-state out-state state-default dup d= ?EXIT
+    in-state state-enabled? out-state state-enabled? and 0= ?EXIT
+    in-state  to state-in
+    out-state to state-out
+    prim reprocess-simple ;
+
+: state-prim ( in-state out-state "name" -- )
+    parse-word lookup-prim state-prim1 ;
+
+\ reprocessing with default states
+
+\ This is a simple scheme and should be generalized
+\ assumes we only cache one stack and use simple states for that
+
+0 value cache-stack  \ stack that we cache
+2variable cache-states \ states of the cache, starting with the empty state
+
+: compute-default-state-out ( n-in -- n-out )
+    \ for the current prim
+    cache-stack stack-in @ - 0 max
+    cache-stack stack-prim-stacks-sync @ if
+	drop 0
+    endif
+    cache-stack stack-out @ + cache-states 2@ nip 1- min ;
+
+: gen-prim-states ( prim -- )
+    to prim
+    cache-states 2@ swap { states } ( nstates )
+    cache-stack stack-in @ +do
+	states i th @
+	states i compute-default-state-out th @
+	prim state-prim1
+    loop ;
+
+: prim-states ( "name" -- )
+    parse-word lookup-prim gen-prim-states ;
+
+: gen-branch-states ( prim -- )
+    \ generate versions that produce state-default; useful for branches
+    to prim
+    cache-states 2@ swap { states } ( nstates )
+    cache-stack stack-in @ +do
+	states i th @ state-default prim state-prim1
+    loop ;
+
+: branch-states ( out-state "name" -- )
+    parse-word lookup-prim gen-branch-states ;
+
+\ producing state transitions
+
+: gen-transitions ( "name" -- )
+    parse-word lookup-prim { prim }
+    cache-states 2@ { states nstates }
+    nstates 0 +do
+	nstates 0 +do
+	    i j <> if
+		states i th @ states j th @ prim state-prim1
+	    endif
+	loop
+    loop ;
+
 \ C output
 
 : print-item { n stack -- }
     \ print nth stack item name
     stack stack-type @ type-c-name 2@ type space
-    ." _" stack stack-pointer 2@ type n 0 .r ;
+    ." MAYBE_UNUSED _" stack stack-pointer 2@ type n 0 .r ;
 
 : print-declarations-combined ( -- )
     max-stacks 0 ?do
@@ -1194,7 +1574,7 @@ variable tail-nextp2 \ xt to execute for
 
 : output-part ( p -- )
     to prim
-    ." /* " prim prim-name 2@ type ."  ( " prim prim-stack-string 2@ type ." ) */" cr
+    ." /* " prim prim-name 2@ prim-type ."  ( " prim prim-stack-string 2@ type ." ) */" cr
     ." NAME(" quote prim prim-name 2@ type quote ." )" cr \ debugging
     ." {" cr
     print-declarations
@@ -1221,8 +1601,8 @@ variable tail-nextp2 \ xt to execute for
     ." {" cr
     ." DEF_CA" cr
     print-declarations-combined
-    ." NEXT_P0;" cr
-    flush-tos
+    output-nextp0
+    spill-state
     \ fetches \ now in parts
     \ print-debug-args
     \ stack-pointer-updates now in parts
@@ -1261,47 +1641,96 @@ variable tail-nextp2 \ xt to execute for
 \ This is intended as initializer for a structure like this
 
 \  struct cost {
-\    int loads;       /* number of stack loads */
-\    int stores;      /* number of stack stores */
-\    int updates;     /* number of stack pointer updates */
-\    int length;      /* number of components */
-\    int *components; /* array of vm_prim indexes of components */
+\    char loads;       /* number of stack loads */
+\    char stores;      /* number of stack stores */
+\    char updates;     /* number of stack pointer updates */
+\    char branch;      /* is it a branch (SET_IP) */
+\    char state_in;    /* state on entry */
+\    char state_out;   /* state on exit */
+\    short offset;     /* offset into super2 table */
+\    char length;      /* number of components */
 \  };
 
 \ How do you know which primitive or combined instruction this
 \ structure refers to?  By the order of cost structures, as in most
 \ other cases.
 
+: super2-length ( -- n )
+    combined if
+	num-combined @
+    else
+	1
+    endif ;
+
 : compute-costs { p -- nloads nstores nupdates }
     \ compute the number of loads, stores, and stack pointer updates
     \ of a primitive or combined instruction; does not take TOS
-    \ caching into account, nor that IP updates are combined with
-    \ other stuff
+    \ caching into account
     0 max-stacks 0 +do
 	p prim-stacks-in i th @ +
     loop
+    super2-length 1- - \ don't count instruction fetches of subsumed insts
     0 max-stacks 0 +do
 	p prim-stacks-out i th @ +
     loop
-    0 max-stacks 0 +do
+    0 max-stacks 1 +do \ don't count ip updates, therefore "1 +do"
 	p prim-stacks-in i th @ p prim-stacks-out i th @ <> -
     loop ;
 
 : output-num-part ( p -- )
-    prim-num @ 4 .r ." ," ;
+    ." N_" prim-c-name-orig 2@ type ." ," ;
+    \ prim-num @ 4 .r ." ," ;
+
+: output-name-comment ( -- )
+    ."  /* " prim prim-name 2@ prim-type ."  */" ;
 
-: output-costs ( -- )
+variable offset-super2  0 offset-super2 ! \ offset into the super2 table
+
+: output-costs-prefix ( -- )
     ." {" prim compute-costs
-    rot 2 .r ." ," swap 2 .r ." ," 2 .r ." ,"
-    combined if
-	num-combined @ 2 .r
-	." , ((int []){" ['] output-num-part map-combined ." })}, /* "
-    else
-	."  1, ((int []){" prim prim-num @ 4 .r ." })}, /* "
-    endif
-    prim prim-name 2@ type ."  */"
+    rot 2 .r ." ," swap 2 .r ." ," 2 .r ." , "
+    prim prim-branch? negate . ." ,"
+    state-in  state-number @ 2 .r ." ,"
+    state-out state-number @ 2 .r ." ,"
+    inst-stream stack-in @ 1 .r ." ,"
+;
+
+: output-costs-gforth-simple ( -- )
+    output-costs-prefix
+    prim output-num-part
+    1 2 .r ." },"
+    output-name-comment
     cr ;
 
+: output-costs-gforth-combined ( -- )
+    output-costs-prefix
+    ." N_START_SUPER+" offset-super2 @ 5 .r ." ,"
+    super2-length dup 2 .r ." }," offset-super2 +!
+    output-name-comment
+    cr ;
+
+\  : output-costs ( -- )
+\      \ description of superinstructions and simple instructions
+\      ." {" prim compute-costs
+\      rot 2 .r ." ," swap 2 .r ." ," 2 .r ." ,"
+\      offset-super2 @ 5 .r ." ,"
+\      super2-length dup 2 .r ." ," offset-super2 +!
+\      inst-stream stack-in @ 1 .r ." },"
+\      output-name-comment
+\      cr ;
+
+: output-super2-simple ( -- )
+    prim prim-c-name 2@ prim prim-c-name-orig 2@ d= if
+	prim output-num-part
+	output-name-comment
+	cr
+    endif ;   
+  
+: output-super2-combined ( -- )
+    ['] output-num-part map-combined 
+    output-name-comment
+    cr ;   
+
 \ the parser
 
 eof-char max-member \ the whole character set + EOF
@@ -1393,7 +1822,11 @@ nl-char singleton eof-char over add-memb
 (( letter (( letter || digit )) **
 )) <- c-ident ( -- )
 
-(( ` # ?? (( letter || digit || ` : )) ++
+(( ` . ` . ` .
+)) <- sync-stack ( -- )
+
+(( ` # ?? (( letter || digit || ` : )) ++ sync-stack ??
+|| sync-stack
 )) <- stack-ident ( -- )
 
 (( nowhitebq nowhite ** ))
@@ -1415,45 +1848,55 @@ Variable c-flag
 )) <- c-comment ( -- )
 
 (( ` - nonl ** {{ 
-	forth-flag @ IF ." [ELSE]" cr THEN
-	c-flag @ IF ." #else" cr THEN }}
+	forth-flag @ IF forth-fdiff ." [ELSE]" cr THEN
+	c-flag @ IF
+	    function-diff
+	    ." #else /* " function-number @ 0 .r ."  */" cr THEN }}
 )) <- else-comment
 
 (( ` + {{ start }} nonl ** {{ end
-	dup
-	IF	c-flag @
-		IF    ." #ifdef HAS_" bounds ?DO  I c@ toupper emit  LOOP cr
-		THEN
-		forth-flag @
-		IF  ." has? " type ."  [IF]"  cr THEN
-	ELSE	2drop
-	    c-flag @      IF  ." #endif"  cr THEN
-	    forth-flag @  IF  ." [THEN]"  cr THEN
+        dup
+        IF
+            c-flag @ IF
+                function-diff
+                ." #ifdef HAS_" 2dup bounds ?DO  I c@ toupper emit  LOOP cr
+            THEN
+            forth-flag @ IF
+                forth-fdiff  ." has? " 2dup type ."  [IF]"  cr
+            THEN
+            2drop
+        ELSE
+            2drop
+	    c-flag @      IF
+		function-diff  ." #endif" cr THEN
+	    forth-flag @  IF  forth-fdiff  ." [THEN]"  cr THEN
 	THEN }}
 )) <- if-comment
 
 (( (( ` g || ` G )) {{ start }} nonl **
    {{ end
-      forth-flag @ IF  ." group " type cr  THEN
-      c-flag @     IF  ." GROUP(" type ." , " function-number @ 0 .r ." )" cr  THEN }}
+      forth-flag @ IF  forth-fdiff  ." group " 2dup type cr  THEN
+      c-flag @     IF  function-diff
+          ." GROUP(" 2dup type ." , " function-number @ 0 .r ." )" cr  THEN
+      2drop }}
 )) <- group-comment
 
 (( (( eval-comment || forth-comment || c-comment || else-comment || if-comment || group-comment )) ?? nonl ** )) <- comment-body
 
 (( ` \ comment-body nleof )) <- comment ( -- )
 
-(( {{ start }} stack-ident {{ end 2 pick init-item item% %size + }} white ** )) **
-<- stack-items
+(( {{ start }} stack-ident {{ end init-item1 }} white ** )) **
+<- stack-items ( addr1 -- addr2 )
 
 (( {{ prim prim-effect-in }}  stack-items {{ prim prim-effect-in-end ! }}
    ` - ` - white **
    {{ prim prim-effect-out }} stack-items {{ prim prim-effect-out-end ! }}
 )) <- stack-effect ( -- )
 
-(( {{ prim create-prim }}
+(( {{ prim create-prim prim init-simple }}
    ` ( white ** {{ start }} stack-effect {{ end prim prim-stack-string 2! }} ` ) white **
    (( {{ start }} forth-ident {{ end prim prim-wordset 2! }} white **
-      (( {{ start }}  c-ident {{ end prim prim-c-name 2! }} )) ??
+      (( {{ start }}  c-ident {{ end prim-c-name-2! }} )) ??
    )) ??  nleof
    (( ` " ` "  {{ start }} (( noquote ++ ` " )) ++ {{ end 1- prim prim-doc 2! }} ` " white ** nleof )) ??
    {{ skipsynclines off line @ c-line ! filename 2@ c-filename 2! start }}
@@ -1475,9 +1918,10 @@ Variable c-flag
       line @ name-line ! filename 2@ name-filename 2!
       function-number @ prim prim-num !
       start }} [ifdef] vmgen c-ident [else] forth-ident [then] {{ end
-      2dup prim prim-name 2! prim prim-c-name 2! }}  white **
-   (( ` / white ** {{ start }} c-ident {{ end prim prim-c-name 2! }} white ** )) ??
-   (( simple-primitive || combined-primitive )) {{ 1 function-number +! }}
+      2dup prim prim-name 2! prim-c-name-2! }}  white **
+   (( ` / white ** {{ start }} c-ident {{ end prim-c-name-2! }} white ** )) ??
+   (( simple-primitive || combined-primitive ))
+   {{ 1 function-number +! }}
 )) <- primitive ( -- )
 
 (( (( comment || primitive || nl white ** )) ** eof ))