FVM - Definitions Glossary

Forth-like for the TI MSP430

Currently under heavy development.

Unstable and Unfinished
Software and Documentation

Definition	Parameters Stack	Remark	MSP430 Cycles	Description
(:)	( --- )	Runtime only	6	Runtime for : (colon definition)
(;)	( --- )	Runtime only	4	Runtime for ; (end of a colon definition)
(BRANCH)	( --- )	Runtime only	4	Unconditional relative branch
(0BRANCH)	(f --- )	Runtime only	no branch: 9 branch: 8	Conditional relative branch: branch if f=0
(==0BRANCH)	(n1 n2 --- )	Runtime only	no branch: 10 branch: 9	Conditional relative branch: branch if the top two 16-bits values are equal
(1BRANCH)	(f --- )	Runtime only	no branch: 9 branch: 8	Conditional relative branch: branch if f is not 0
NOP	( --- )		3	No OPeration
(cold)	( --- )			Perform a cold restart
(warm)	( --- )			Perform a warm restart

Code for the Forth VM is here (MSP430) and also here (x86 Linux).

Definition	Parameters Stack	Remark	MSP430 Cycles	Description
(LIT)	( --- n1)	Runtime only	4	Push on the stack a 16-bits literal
SP!	(… --- )		4	Empty the stack
DEPTH	(… --- n)		6	Number of 16-bits numbers on the stack
SWAP	(n1 n2 --- n2 n1)		14	Exchange the top 16-bits two values on stack
DUP	(n --- n n)		4	Duplicate the 16-bits value on top of the stack
OVER	(n1 n2 --- n1 n2 n2)		5	Duplicate the 16-bits value under the top of the stack
ABOVE	(n1 n2 n3 --- n1 n2 n3 n1)		5	Duplicate the 16-bits value under under the top of the stack
TUCK	(n1 n2 --- n2 n1 n2)		14	SWAP OVER
DROP	(n --- )		3	Discard the 16-bits value from the top of the stack
UNDER	(n1 n2 --- n2)		7	Discard the 16-bits value under the top of the stack
BELOW	(n1 n2 n3 --- n2 n3)		13	Discard the 16-bits value under under the top of the stack
ROT	(n1 n2 n3 --- n2 n3 n1)		20	Rotate the top three 16-bits value on top of the stack
-ROT	(n1 n2 n3 --- n3 n1 n2)		20	Rotate the top three 16-bits value on top of the stack

Code for Stack Operations (16-bits) is here (MSP430) and also here (x86 Linux).

Definition	Parameters Stack	Remark	MSP430 Cycles	Description
(DLIT)	( --- d1)	Runtime only	15	Push on the stack a 36-bits literal
DSWAP	(d1 d2 --- d2 d1)		28	Exchange the top two 32-bits values on stack
DDUP	(d --- d d)		18	Duplicate the 32-bits value on top of the stack
DOVER	(d1 d2 --- d1 d2 d2)		19	Duplicate the 32-bits value under the top of the stack
DABOVE	(d1 d2 d3 --- d1 d2 d3 d1)		19	Duplicate the 32-bits value under under the top of the stack
DTUCK	(d1 d2 --- d2 d1 d2)		37	DSWAP DOVER
DDROP	(d --- )		3	Discard the 32-bits value from the top of the stack
DUNDER	(d1 d2 --- d2)		12	Discard the 32-bits value under the top of the stack
DBELOW	(d1 d2 d3 --- d2 d3)		26	Discard the 32-bits value under under the top of the stack
DROT	(d1 d2 d3 --- d2 d3 d1)		45	Rotate the top three 32-bits value on top of the stack
-DROT	(d1 d2 d3 --- d3 d1 d2)		45	Rotate the top three 32-bits value on top of the stack

Code for Stack Operations (32-bits) is here (MSP430) and also here (x86 Linux).

Definition	Parameters Stack	Return Stack	Remark	MSP430 Cycles	Description

RP!		(… --- )		4	Empty the return stack
>R	(n --- )	( --- n)		6	Push a value to the return stack
R>	( --- n)	(n --- )		9	Pop a value from the return stack.
R	( --- n)	(n --- n)		9	Push onto the parameters stack the value from the top of the return stack
RDROP		(n --- )		4	Discard the value on top of the return stack
(do)	(n1 n2 --- )	( --- n1 n2)	Runtime only	Can do: 20 no loop: 12	Runtime for DO: n1:limit n2:index
(loop)		(n1 n2 --- n1 n3)	Runtime only	16	Runtime for LOOP:
(+loop)	(n --- )	(n1 n2 --- n1 n3)	Runtime only	16	Runtime for +LOOP:
(lit+loop)		(n1 n2 --- n1 n3)	Runtime only	7	Runtime for +LOOP (with a compiled literal value):
(J)	( --- n)	(n1 n2 n3 n4 --- n1 n2 n3 n4)		10
(K)	( --- n)	(n1 n2 n3 n4 n5 n6 --- n1 n2 n3 n4 n5 n6)		10
(local)		( --- n1 n2 … )	Runtime only	5
(leave)		(n1 n2 … --- )	Runtime only	4

Code for Stack Operations (16-bits) is here (MSP430) and also here (x86 Linux).

Code for Integer Arithmetic (16-bits) is here (MSP430) and also here (x86 Linux).