number571 / cvm

Stack-based virtual machine written in C.

VirtualMachine

Stack-based virtual machine. Version 1.0.4.

Pseudo instructions

Code	Instruction
0x11	";" (comment)
0x22	"labl" (label)

Null instructions

Code	Instruction
0xAA	(void string)
0xBB	(undefined code)

Main instructions

Bytecode	Stack	Args	Instruction
0x0A	0	1	push
0x0B	1	0	pop
0x0C	1	0	inc
0x0D	1	0	dec
0x0E	3	0	jg
0x0F	3	0	je
0x1A	1	0	jmp
0x1B	2	0	stor
0x1C	1	0	load
0x1D	1	0	call
0x1E	0	0	hlt

Interface functions

extern int cvm_compile(FILE *output, FILE *input);
extern int cvm_load(uint8_t *memory, int32_t msize);
extern int cvm_run(int32_t **output, int32_t *input);

Additional instructions

Bytecode	Stack	Args	Instruction
0xA0	2	0	add
0xB0	2	0	sub
0xC0	2	0	mul
0xD0	2	0	div
0xE0	2	0	mod
0xF0	2	0	shr
0xA1	2	0	shl
0xB1	2	0	xor
0xC1	2	0	and
0xD1	2	0	or
0xE1	1	0	not
0xF1	3	0	jl
0xA2	3	0	jne
0xB2	3	0	jle
0xC2	3	0	jge
0xD2	1	0	allc

Compile and run

$ make install
> git clone https://github.com/number571/extclib.git
$ make 
> gcc -o cvm -Wall -std=c99 cvm.c cvmkernel.c extclib/type/stack.c extclib/type/hashtab.c extclib/type/list.c 
> ./cvm build main.vms -o main.vme
> ./cvm run main.vme
> 
{
	"result": [50],
	"return": 0
}

Example: mul5 function (assembly code)

labl _start
	push begin 
	jmp

; main
labl begin
	; mul5(x) = x * 5
	; where x = 10
	push 10
	push mul5
	call
	push end
	jmp	

; exit 
labl end
	hlt

; x = arg[1]
labl mul5
	; y = x * 5
	push -2
	load 
	push 5
	mul

	; x = y
	push -1
	push -3
	stor 

	; return
	pop
	jmp

Example: mul5 function (binary code)

0a00 0000 061a 0a00 0000 0a0a 0000 0018
1d0a 0000 0017 1a1e 0aff ffff fe1c 0a00
0000 05c0 0aff ffff ff0a ffff fffd 1b0b
1a