rajamesandClaude Opus 5.5
482cc75faf
(GATE) offers a message's first word and sleeps until it is taken, taking in whatever is written to the node meanwhile; (PAY) offers every refusal owed at once, one to a port; a node that owes one sleeps in the wait. Writing without looking, looking again and again, and the lower-number rule are gone. Text from the console for a node whose own text waits to begin a message ends that text Interrupted. The lone node's hosts serve an offer as a write. MESH.md 7c; plan step 6d task 2. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
406 lines
18 KiB
Plaintext
406 lines
18 KiB
Plaintext
\ core.v4 -- the core words the host-node capsules rest on.
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\
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\ Each is the definition DECOMPOSITION.md gives and the golden-model tests
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\ execute (test_foundation.c, test_strings.c, test_terminal.c, test_pictured.c),
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\ written here as text for the text assembler (v4/include/v4/text.h).
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\
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\ Constants the loader supplies: N-1 (cell bits - 1), NODE-ERROR, CONSOLE-TX,
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\ CONSOLE-RX, CONSOLE-STATUS, BASE, (MSG), (REPLY), (ME), (OUT),
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\ (OUT^), (CONSOLE), (ROUTES), (ROUTE#), (ROUTE-DEFAULT), (PRINT-TO),
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\ (PRINT-PORT).
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\
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\ ERRORS (D-18). A word that finds an error takes its arguments off the stack
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\ and stores a code in NODE-ERROR. On a node with a prompt that store is a
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\ trap: the word goes no further, and the prompt prints the message for the
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\ code and ERROR (quit.v4, (RAISED)). The codes:
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\ 1 Negative count 2 Not a number 3 Number too long
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\ 4 Not a character 5 Dictionary full 6 Name missing
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\ 7 Control structure mismatch 8 Control structures too deep
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\ 9 Shift count out of range 10 Protected word
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\ 11 Division by zero (Q./) 12 Argument out of range
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\ 13 Block out of range 14 No block is being loaded
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\ 15 Deferred word not set 16 Not a word
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\ 17 Storage refused 18 No one on that port
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\ 19 Message refused 20 Node gone
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\ 21 Interrupted
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\ -1 the word has printed its own message
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macro SWAP over push push drop pop pop endmacro
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macro - push inv pop + inv endmacro \ x y -- x-y
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macro NEGATE inv 1 + endmacro
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macro NIP push drop pop endmacro
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\ ---- section 4: multiply ------------------------------------------------
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header UM*
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: UM* ( u1 u2 -- ulo uhi )
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over 1 and inv 1 + over 2/ and \ u1 u2 t0 t0 = u2 2/ if u1 odd
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over a! N-1 push \ A: u2 R: loop count
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push over 2/ pop \ u1 u2 s t0 s = u1 2/
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L: +* unext \ u1 u2 s hi A: lo
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push drop pop \ u1 u2 hi
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2* a -if L0 drop 1 + jump L1 L0: drop L1: push
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over -if L2 drop dup jump L3 L2: drop 0 L3: push
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dup -if L4 drop over 1 and jump L5 L4: drop 0 L5:
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pop + pop + push
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and 1 and a 2* + pop ;
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\ ---- section 5.7: doubles ------------------------------------------------
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header D+
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: D+ ( d1 d2 -- d3 )
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push over push push drop pop \ al bl R: bh ah
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over over xor -if L1
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drop + -if C1 jump C0
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L1: drop over -if L2
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drop + jump C1
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L2: drop +
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C0: pop pop + ;
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C1: pop pop + 1 + ;
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header DNEGATE
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: DNEGATE ( d -- -d )
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inv over if L1 drop push inv 1 + pop ;
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L1: drop 1 + ;
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\ ---- section 5.3: bytes --------------------------------------------------
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\ The shifts are written out, eight to a line, where DECOMPOSITION.md 5.3 has
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\ a FOR ... UNEXT loop: a loop keeps its count on the return stack, and C@ and
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\ C! are at the bottom of every chain of calls in the compiler capsule, where
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\ there is not an entry to spare (D-2). The result is the same.
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macro 8/ 2/ 2/ 2/ 2/ 2/ 2/ 2/ 2/ endmacro
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macro 8* 2* 2* 2* 2* 2* 2* 2* 2* endmacro
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header C@
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: C@ ( baddr -- c )
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dup 2/ 2/ a! 3 and
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if K0 -1 + if K1 -1 + if K2
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drop @ 8/ 8/ 8/ 255 and ;
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K2: drop @ 8/ 8/ 255 and ;
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K1: drop @ 8/ 255 and ;
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K0: drop @ 255 and ;
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header C!
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: C! ( c baddr -- )
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dup 2/ 2/ a! 3 and
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if K0 -1 + if K1 -1 + if K2
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drop 8* 8* 8* 4278190080 and @ 4278190080 inv and + ! ;
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K2: drop 8* 8* 16711680 and @ -16711681 and + ! ;
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K1: drop 8* 65280 and @ -65281 and + ! ;
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K0: drop 255 and @ -256 and + ! ;
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\ ---- section 5.9: strings ------------------------------------------------
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header CMOVE
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: CMOVE ( src dst u -- )
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-if OK drop drop drop NODE-ERROR b! 1 !b ;
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OK: if DONE push
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over C@ over C! 1 + push 1 + pop pop -1 + jump OK
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DONE: drop drop drop ;
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\ ---- section 5.10: the console -------------------------------------------
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\ ---- what a node prints (docs/v4.0.0/MESH.md section 6) ------------------------
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\ A node has no console of its own. It does what a message asks, and what
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\ it prints while doing it is sent as a message: to the node in (CONSOLE), or
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\ if that is 0 to whoever sent the text; by the port that leads there, or if
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\ this node knows of none, by the port the text came on. A message is seven words and then its text, four
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\ characters to a word:
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\ to, from, type, heat and TTL, ACL tag, sequence, length in characters
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\ The types: 1 text to be interpreted 2 what a node printed 3 how the
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\ text ended (one word of text: 0 QUIT, 1 completed, 2 an error).
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\ The header of the message being served is in the seven cells (MSG); (REPLY)
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\ is the address of the port it came on; (ME) is this node's number.
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\
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\ Characters are kept in (OUT), 256 of them, a character to a cell, and sent
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\ when it is full and when the text has been done with (quit.v4). (OUT^)
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\ is where the next goes.
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\
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\ THE STACK. What prints may be run with the data stack all but full: EMIT
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\ has always needed one free cell and no more, and still does -- it keeps
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\ the character and A on the return stack while it works. Sending needs
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\ two.
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\ FINDING THE WAY (MESH.md section 7). A node knows its ports and nothing of
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\ the shape they are wired in. Whoever wires it tells it, for a node, which
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\ port leads toward that node: the table (ROUTES), (ROUTE#) entries of a
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\ node's number and a port's address; and (ROUTE-DEFAULT), the port for any
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\ node that is not in the table, or 0.
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\ ( node -- port | 0 ) the address of the port that leads toward the node
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: (PORT-FOR)
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(ROUTE#) a! @ if NONE -1 + (ROUTES) a!
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FOR dup @+ xor if HIT drop @+ drop NEXT
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0
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NONE: drop drop (ROUTE-DEFAULT) a! @ ;
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HIT: drop drop @+ pop drop ;
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\ BEGINNING A MESSAGE: THE WAIT (MESH.md section 7c). A write waits until
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\ the neighbour reads, and a node that is waiting to write reads nothing:
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\ two neighbours that each began to write to the other would wait for ever,
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\ and a node that wrote to one that was stuck would be stuck with it. So
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\ a node does not write the first word of a message. It offers it, (GATE):
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\ the word is stored at the port's offer address, and the node then reads
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\ the wait, where it sleeps until the offer is taken or a word comes for
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\ it, whichever is first. If a word comes, that message is taken in and
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\ kept with the messages waiting, and the node offers again. When the
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\ offer is taken the neighbour has the first word and reads to the end:
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\ the rest is written, each word waiting for it.
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\ (OFFER) is the offer address of port 0, and (WAIT) the wait. (READERS)
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\ is the node's look at its neighbours, a bit for each port that has one
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\ waiting to read, and above those a bit for each port that has anything
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\ on it at all. (NEAR) is the number of the node on each port, told by
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\ whoever wires it (NEIGHBOUR, quit.v4): it is how a node knows its centre.
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\
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\ THE MESSAGES WAITING are kept in (MQ) .. (MQ-END), one after another,
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\ going round: for each its seven words, the port it came on, and its text.
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\ (MQ-HEAD) is where the oldest begins, (MQ-TAIL) where the next will go,
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\ (MQ#) how many cells are taken. One that there is no room for is read to
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\ its end and let go, and (LOST) counts it.
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\ ( mask index -- bit )
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: (BIT)
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if Z -1 + FOR 2/ NEXT 1 and ;
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Z: drop 1 and ;
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\ ( w -- ) one more cell of the messages waiting. B is kept.
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: (MQ!)
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(MQ-TAIL) a! @ a! !+
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a (MQ-END) xor if WRAP drop a jump SET
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WRAP: drop (MQ)
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SET: (MQ-TAIL) a! !
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(MQ#) a! @ 1 + ! ;
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\ ( -- w ) the oldest cell of the messages waiting, which goes
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: (MQ@)
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(MQ-HEAD) a! @ a! @+
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a (MQ-END) xor if WRAP drop a jump SET
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WRAP: drop (MQ)
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SET: (MQ-HEAD) a! !
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(MQ#) a! @ -1 + ! ;
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\ REFUSALS (MESH.md section 7b). A message this node has no room for, or
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\ no way to pass on, is let go and counted in (LOST); and its sender is
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\ told, by a message of type 4, a NACK, whose one word is the node the
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\ refused message was for. A node finds it has no room while it is taking
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\ messages in so as to be free to write, where it cannot begin a message
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\ of its own: so it notes what it owes, (OWE), in the eight pairs at
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\ (OWED) -- whom it is owed to, and the node the message was for -- and
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\ sends it when it next has nothing else to do, (PAY). With eight owed
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\ already, one more is let go and counted. Nothing is owed for a NACK or
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\ for a GONE, type 5: there is no NACK for a NACK. The last 36 cells of
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\ the messages waiting are kept for those two types, so that ordinary
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\ messages cannot take all the room.
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\ ( to about -- ) a refusal is owed to the node `to`, about the node `about`.
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\ Owed to this node itself -- its own message came back to it and was let
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\ go here -- it is put with the messages waiting, as if it had come by a
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\ port, in the room kept for refusals.
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: (OWE)
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over (ME) a! @ xor if SELF drop
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(OWED#) a! @ -8 + -if NOROOM
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drop (OWED#) a! @ 2* (OWED) + a!
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push !+ pop !
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(OWED#) a! @ 1 + ! ;
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SELF: drop 1 (MQ#) a! @ + -MQ-ROOM + -if NOROOM
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drop push (MQ!) (ME) a! @ (MQ!) 4 (MQ!) 0 (MQ!) 0 (MQ!) 0 (MQ!) 4 (MQ!) 0 (MQ!) pop (MQ!) ;
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NOROOM: drop drop drop (LOST) a! @ 1 + ! ;
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\ ( from to type -- ) a message of that type, from the one node for the
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\ other, has been let go here. Whoever is waiting on it is told: its
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\ sender; or, for a node's answer (type 3), the node the answer was for,
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\ which is the one that waits. Nothing is owed for a NACK or a GONE.
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: (TELL-OF)
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dup -4 + if NOT -1 + if NOT drop
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-3 + if ANSWER drop jump (OWE) \ to its sender, about whom it was for
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ANSWER: drop SWAP jump (OWE) \ to whom it was for, about the node that answered
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NOT: drop drop drop drop ;
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\ ( port -- flag ) is there anything on that port, by its address?
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: (THERE)
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(PORT) - -PORTS - (READERS) b! @b SWAP jump (BIT)
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\ ( port to -- ) the seven words of a message being taken in, and the
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\ port, go into (MQ-HDR). B is at the port, by its address, and `to` is
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\ the message's first word, already read from it.
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: (TAKE-HDR)
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(MQ-HDR) a! !+ 5 FOR @b !+ UNEXT ! ;
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\ ( -- ) the message whose seven words are in (MQ-HDR) is kept with the
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\ messages waiting: its text is read from the port B is at. A length
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\ below zero, or above what a message carries, is kept as -1 with no text:
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\ a longer one is read to its end first, so that what follows it is not
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\ taken for a message.
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: (TAKE-KEEP)
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(MQ-HDR)+6 a! @ -if SIZED
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drop -1 (MQ-HDR)+6 a! ! 0 jump COUNTED
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SIZED: dup -1025 + -if LONG drop 3 + 2/ 2/ jump COUNTED
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LONG: drop 3 + 2/ 2/ -1 + FOR @b drop UNEXT -1 (MQ-HDR)+6 a! ! 0
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COUNTED: \ ( n ) how many words of text follow
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dup (MQ#) a! @ + \ what it would come to
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(MQ-HDR)+2 a! @ -4 + if KEPT-FOR -1 + if KEPT-FOR \ a NACK or a GONE may use the room kept for them
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drop -MQ-ORDINARY + jump ROOM
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KEPT-FOR: drop -MQ-ROOM +
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ROOM: -if FULL
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drop push
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(MQ-HDR) a! @ (MQ!) (MQ-HDR)+1 a! @ (MQ!) (MQ-HDR)+2 a! @ (MQ!) (MQ-HDR)+3 a! @ (MQ!)
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(MQ-HDR)+4 a! @ (MQ!) (MQ-HDR)+5 a! @ (MQ!) (MQ-HDR)+6 a! @ (MQ!) (MQ-HDR)+7 a! @ (MQ!)
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pop if NOTEXT -1 + FOR @b (MQ!) NEXT ;
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NOTEXT: drop ;
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FULL: drop if READ -1 + FOR @b drop UNEXT jump LOSE
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READ: drop
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LOSE: (LOST) a! @ 1 + !
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(MQ-HDR)+1 a! @ (MQ-HDR) a! @ (MQ-HDR)+2 a! @ jump (TELL-OF)
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\ ( port to -- ) take in a message and keep it
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: (TAKE) (TAKE-HDR) jump (TAKE-KEEP)
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\ ( -- flag ) THE WAIT, once. Whatever has been offered stands until
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\ this returns. Zero: a word came for this node instead; that whole
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\ message has been taken in and kept, (TAKE), and its seven words are
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\ still in (MQ-HDR). Not zero: an offer was taken; B is at the port it
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\ was taken on, and (GATE-PORT) holds that port's address.
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: (OFFERS)
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(WAIT) b! @b push (PORT)+9 b! @b \ ( which ) R: the word
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dup -PORTS + -if TAKEN
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drop (PORT) + dup b! pop (TAKE) 0 ; \ a word, from that port: the message's first
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TAKEN: (PORT) + (GATE-PORT) a! ! drop pop drop
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(GATE-PORT) a! @ b! -1 ;
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\ ( w port -- ) BEGIN A MESSAGE: the word, its first, is offered on the
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\ port, by its address, until it is taken; whatever is written to this
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\ node meanwhile is taken in. B is left at the port. The two are kept in
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\ (GATE-WORD) and (GATE-PORT), not on the stack: (GATE1), which is this
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\ with the word already in (GATE-WORD), is run with the stack as full as
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\ EMIT may be.
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\ TEXT FROM THE CONSOLE for this node, coming while text it is doing waits
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\ here, ends that text in error 21, Interrupted (MESH.md 7c.3); it is with
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\ the messages waiting and is done next. It is how a node whose text must
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\ begin a message to a node that is stuck is typed to. Not while (QUIET)
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\ is set: what waits then is no text's doing.
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\ With nothing on the port the fabric raises error 18.
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: (GATE1) ( port -- )
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(GATE-PORT) a! !
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L: (GATE-WORD) a! @ (GATE-PORT) a! @ -PORTS - 4 + a! ! \ the offer
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(OFFERS) if CAME drop ;
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CAME: drop
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(QUIET) a! @ if TEXTS drop jump L
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TEXTS: drop
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(MQ-HDR) a! @ (ME) a! @ xor if MINE drop jump L
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MINE: drop
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(MQ-HDR)+2 a! @ -1 + if TEXT drop jump L
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TEXT: drop
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(CONSOLE) a! @ if C0 jump C1
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C0: drop (MSG)+1 a! @ \ no console told of: whoever sent the text being done
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C1: (MQ-HDR)+1 a! @ xor if BREAK drop jump L
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BREAK: drop NODE-ERROR b! 21 !b ;
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: (GATE) ( w port -- ) push (GATE-WORD) a! ! pop jump (GATE1)
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\ ( type -- ) words 1 to 5 of a message this node sends: from, type, and
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\ the three that are carried and not used yet. Its caller has put B at the
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\ port and sent word 0, whom it is to, and sends the length and the text.
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\ Each write waits for the neighbour to take it.
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: (HDR)
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(ME) a! @ !b \ from
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!b \ type
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16 !b 0 !b 0 !b ; \ how many nodes may pass it on (the TTL: MESH.md 7b); ACL tag; sequence
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\ PAYING WHAT IS OWED (MESH.md 7c.3). Every refusal owed is offered at
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\ once, each on the port it goes by, one to a port, and the node sleeps in
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\ the wait: so one owed to a node that is stuck does not keep back one
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\ owed to a node that waits for it, and the node takes in whatever is
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\ written to it meanwhile. One there is no way for, or whose way is a
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\ port with nothing on it, is let go and counted first. (PAY-K) has a
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\ cell for each port: which refusal is offered there, counted from 1; 0,
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\ none.
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\ ( k -- ) the k-th refusal owed is done with: the last takes its place
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: (PAID)
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(OWED#) a! @ -1 + dup !
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2* (OWED) + a! @+ @
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push push 2* (OWED) + a! pop !+ pop ! ;
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\ ( k -- ) the k-th refusal owed is let go if it cannot be sent at all
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: (PAY-DROP)
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dup 2* (OWED) + a! @ \ k to
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(PORT-FOR) if NOWAY \ k port
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(THERE) if GONE drop drop ;
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GONE:
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NOWAY: drop (LOST) a! @ 1 + ! jump (PAID)
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\ ( k -- ) offer the k-th refusal owed on its port, if nothing is there yet
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: (PAY-OFFER)
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dup 2* (OWED) + a! @ \ k to
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dup (PORT-FOR) (PORT) - \ k to n the port, by its number
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dup (PAY-K) + a! @ if FREE
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drop drop drop drop ;
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FREE: drop
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dup push (OFFER) + a! ! \ k the message's first word, whom it is to
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1 + pop (PAY-K) + a! ! ;
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\ ( -- flag ) offer every refusal this node owes and wait once: if one
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\ is taken its other words are written and it is done with. Zero if
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\ nothing is owed, and then nothing was waited for.
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: (PAY)
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(OWED#) a! @ if NONE
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-1 + FOR pop dup push (PAY-DROP) NEXT
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(OWED#) a! @ if NONE
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(PAY-K) a! PORTS-1 FOR 0 !+ NEXT
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-1 + FOR pop dup push (PAY-OFFER) NEXT
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(OFFERS) if CAME
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drop (GATE-PORT) a! @ (PORT) - (PAY-K) + a! @ -1 + \ k: the one that was taken
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dup 2* (OWED) + 1 + a! @ \ k about
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4 (HDR) 4 !b !b \ from, type 4; four characters; about
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(PAID) -1 ;
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CAME: drop -1 ;
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NONE: drop 0 ;
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\ ( -- ) send what has been printed, to where (PRINT-TO) says, by the port
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\ (PRINT-PORT): its length, then its characters, four to a word, the first
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\ lowest. quit.v4 sets those two when text for this node arrives.
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: (FLUSH-OUT)
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(OUT^) a! @ (OUT) xor if NONE drop
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(PRINT-TO) a! @ (GATE-WORD) a! ! (PRINT-PORT) a! @ (GATE1)
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2 (HDR)
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(OUT^) a! @ (OUT) - dup !b
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3 + 2/ 2/ -1 + (OUT) a!
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FOR @+ @+ 8* + @+ 8* 8* + @+ 8* 8* 8* + !b NEXT
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(OUT) (OUT^) a! ! ;
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NONE: drop ;
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\ EMIT puts the character with what has been printed. Everything the node
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\ prints goes through EMIT. A is kept: the words that print have always
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\ been free to use it across an EMIT. As v3, only the low 8 bits of the
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\ character are printed.
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header EMIT
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: EMIT ( c -- )
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255 and a push push \ A, and then the character, to the return stack
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(OUT^) b! @b a! pop !+ a !b \ the character goes where (OUT^) points, which moves on
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a (OUT)+256 xor if FULL drop pop a! ;
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FULL: drop (FLUSH-OUT) pop a! ;
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header KEY
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: KEY ( -- c )
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L: CONSOLE-STATUS b! @b if WAIT drop CONSOLE-RX b! @b ;
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WAIT: drop jump L
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header CR
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: CR ( -- ) 10 jump EMIT
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header SPACE
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: SPACE ( -- ) 32 jump EMIT
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header COUNT
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: COUNT ( baddr -- baddr+1 c ) dup C@ push 1 + pop ;
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header TYPE
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: TYPE ( baddr u -- )
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-if OK drop drop NODE-ERROR b! 1 !b ;
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OK: if DONE over C@ EMIT push 1 + pop -1 + jump OK
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DONE: drop drop ;
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\ ( x -- ) up to four characters packed in one cell, the first in the low
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\ byte: how the capsule prints its own short messages, a literal at a time.
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: (EMIT4)
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L: if DONE dup EMIT 8/ jump L
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DONE: drop ;
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\ ---- section 5.8: the number base ----------------------------------------
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: (BASE) ( -- b ) \ BASE, or 10 when it is outside 2 .. 36
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BASE b! @b dup -2 + -if L1 drop drop 10 ;
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L1: drop dup -37 + -if L2 drop ;
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L2: drop drop 10 ;
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