path: root/svp.cpu

info
	prefix svp_
	opcode_size 16
	body svp_run_op
	
regs
	internal 16 scratch1 x y scratch2 st pad pc
	a 32
	stack 16 stack0 stack1 stack2 stack3 stack4 stack5
	stackidx 8
	p 32
	external 16 pm0 pm1 pm2 xst pm4 ext5 pmc
	pointers0 8 r0 r1 r2 r3 
	pointers1 8 r4 r5 r6 r7
	iram 16 1024
	ram0 16 256
	ram1 16 256
	zflag 8
	nflag 8
	rpl 16
	
flags
	register st
	Z 13 zero zflag
	N 15 sign nflag
	R 0-2 none rpl
	
svp_pop
	mov stack.stackidx dst
	add 1 stackidx stackidx
	switch stackidx
	case 6
	mov 0 stackidx
	end
	
svp_push
	arg src 16
	add -1 stackidx stackidx
	switch stackidx
	case -1
	mov 5 stackidx
	end
	mov src stack.stackidx
	
svp_ram_read
	arg mode 16
	arg banki 16
	arg regi 16
	local idx 16
	
	switch banki
	case 0
	meta bank ram0
	meta reg pointers0.regi
	
	default
	meta bank ram1
	meta reg pointers1.regi
	end
	
	mov reg idx
	switch mode
	case 0
	meta modestr ""
	
	case 1
	meta modestr +!
	add 1 reg reg
	
	case 2
	#loop decremenet
	meta modestr -
	mov reg tmp
	switch rpl
		case 0
		sub 1 reg reg
		
		default
		lsl 1 rpl rpl
		sub 1 rpl rpl
		local mask 16
		not rpl mask
		and reg mask reg
		sub 1 tmp tmp
		and rpl tmp tmp
		or rpl reg reg
		
		end
	
	case 3
	#loop increment
	meta modestr +
	
	and 7 st rpl
	switch rpl
		case 0
		sub 1 reg reg
		
		default
		mov reg tmp
		lsl 1 rpl rpl
		sub 1 rpl rpl
		local mask 16
		not rpl mask
		and reg mask reg
		add 1 tmp tmp
		and rpl tmp tmp
		or rpl reg reg
		
		end
	end
	
	and 255 idx idx
	meta val bank.idx
	
svp_read_ext
	arg regidxr 16
	switch regidxr
	case 7
	meta val a
	
	default
	#TODO: PMAR stuff
	meta val external.regidxr
	end
	
svp_write_ext
	arg regidxw 16
	switch regidxw
	case 7
	and 0xFFFF0000 a a
	or src a a
	
	default
	#TODO: PMAR stuff
	mov src external.regidxw
	end
	
svp_alu_op
	arg P 16
	arg param 32
	
	switch P
	case 1
	dis "sub %s" name
	sub param a a
	
	case 3
	dis "cmp %s" name
	cmp param a
	
	case 4
	dis "add %s" name
	add param a a
	
	case 5
	dis "and %s" name
	and param a a
	
	case 6
	dis "or %s" name
	or param a a
	
	case 7
	dis "eor %s" name
	xor param a a
	end
	update_flags ZN
	
svp_check_cond
	arg fval 16
	arg cond 16
	local invert 8
	switch cond
	case 0
	meta flag 1
	
	case 5
	meta flag zflag
	
	case 7
	meta flag nflag
	
	default
	meta flag 0
	end
	switch fval
	case 0
	lnot flag invert
	meta istrue invert 
	
	default
	meta istrue flag
	end
	
PPP0000000000000 alu_n1
	invalid P 0
	invalid P 2
	meta name "-"
	svp_alu_op P 0xFFFF0000
	
PPP0000000000RRR alu_r
	invalid P 0
	invalid P 2
	local tmp 32 
	lsl internal.R 16 tmp
	meta name internal.R
	svp_alu_op P tmp
	
PPP0000000000011 alu_a
	invalid P 0
	invalid P 2
	svp_alu_op P a
	
PPP0000000000101 alu_stack
	invalid P 0
	invalid P 2
	local tmp 32
	meta dst tmp
	svp_pop
	meta name "st"
	svp_alu_op P tmp
	
PPP0000000000111 alu_p
	invalid P 0
	invalid P 2
	meta name p
	svp_alu_op P p
	
PPP0000000001RRR alu_ext
	invalid P 0
	invalid P 2
	local tmp 32
	svp_read_ext R
	lsl val 16 tmp
	meta name val
	svp_alu_op P tmp
	
PPP0001B000MMRR alu_ram
	invalid P 0
	invalid P 2
	svp_ram_read M B R
	local tmp 32
	lsl val 16 tmp
	
	switch P
	case 1
	dis "sub (%s%s)" reg modestr
	sub tmp a a
	
	case 3
	dis "cmp (%s%s)" reg modestr
	cmp tmp a
	
	case 4
	dis "add (%s%s)" reg modestr
	add tmp a a
	
	case 5
	dis "and (%s%s)" reg modestr
	and tmp a a
	
	case 6
	dis "or (%s%s)" reg modestr
	or tmp a a
	
	case 7
	dis "eor (%s%s)" reg modestr
	xor tmp a a
	end
	
	update_flags ZN
	
PPP0000000001111 alu_al
	invalid P 0
	invalid P 2
	local tmp 32
	lsl a 16 tmp
	
	meta name al
	svp_alu_op P tmp
	
1001000FCCCC0OOO cond_mod
	svp_check_cond F C
	switch istrue
	case 0
	
	default
	switch O
	case 2
	asr a 1 a
	update_flags ZN
	
	case 3
	lsl a 1 a
	update_flags ZN
	
	case 6
	neg a a
	update_flags ZN
	
	case 7
	abs a a
	update_flags N
	end

000000000DDD0SSS ld_int_int
	dis "ld %s, %s" internal.D internal.S
	mov internal.S internal.D
	
000000000DDD0101 ld_int_st
	dis "ld %s, st" internal.D 
	meta dst internal.D
	svp_pop
	
0000000000110101 ld_a_st
	dis "ld a, st"
	local tmp 32
	meta dst tmp
	svp_pop
	lsl tmp 16 tmp
	and 0xFFFF a a
	or tmp a a
	
0000000001110101 ld_p_st
	dis "ld p, st"
	local tmp 32
	meta dst tmp
	svp_pop
	lsl tmp 16 tmp
	and 0xFFFF p p
	or tmp p p
	
0000000001010SSS ld_st_int
	dis "ld st, %s" internal.S
	svp_push internal.S
	
0000000001010011 ld_st_a
	dis "ld st, a"
	local tmp 32
	lsr a 16 tmp
	svp_push tmp
	
0000000001010111 ld_st_p
	dis "ld st, p"
	local tmp 32
	lsr p 16 tmp
	svp_push tmp
	
0000000000000000 ld_n1_n1
	#nop?
	dis "ld -, -"
	
0000000000000SSS ld_n1_int
	#nop?
	dis "nop??"
	
0000000000110111 ld_a_p
	dis "ld a, p"
	mov p a
	
0000000001110011 ld_p_a
	dis "ld p, a"
	mov a p
	
0000000000110011 ld_a_a
	dis "ld a, a"
	mov a a
	
0000000001110111 ld_p_p
	dis "ld p, p"
	mov p p

000000000DDD0111 ld_int_p
	local tmp 32
	lsr p 16 tmp
	mov tmp internal.D
	dis "ld %s, p" internal.D
	
000000000DDD0111 ld_int_a
	local tmp 32
	lsr a 16 tmp
	mov tmp internal.D
	dis "ld %s, a" internal.D
	
0000000001110SSS ld_p_int
	local tmp 32
	lsl internal.S 16 tmp
	mov tmp p
	dis "ld p, %s" internal.S
	
0000000000110SSS ld_a_int
	local tmp 32
	lsl internal.S 16 tmp
	mov tmp a
	dis "ld a, %s" internal.S
	
000000000DDD0000 ld_int_n1
	dis "ld %s, -" internal.D
	mov 0xFFFF internal.D
	
0000000000110000 ld_a_n1
	dis "ld a, -"
	and 0xFFFF a a
	or 0xFFFF0000 a a
	
0000000001110000 ld_p_n1
	dis "ld p, -"
	and 0xFFFF p p
	or 0xFFFF0000 p p

000000000DDD1SSS ld_int_ext
	svp_read_ext S
	dis "ld %s, %s" internal.D val
	mov val internal.D
	
0000000000111SSS ld_a_ext
	svp_read_ext S
	dis "ld a, %s" val
	local tmp 32
	lsl val 16 tmp
	and 0xFFFF a a
	or tmp a a
	
0000000001111SSS ld_p_ext
	svp_read_ext S
	dis "ld p, %s" val
	local tmp 32
	lsl val 16 tmp
	and 0xFFFF p p
	or tmp p p
	
000000001DDD0SSS ld_ext_int
	meta src internal.S
	svp_write_ext D
	switch D
	case 7
	dis "ld al, %s" src
	
	default
	dis "ld %s, %s" external.D src
	end
	
000000001DDD0011 ld_ext_a
	local tmp 32
	lsr a 16 tmp
	meta src tmp
	svp_write_ext D
	switch D
	case 7
	dis "ld al, a"
	
	default
	dis "ld %s, a" external.D
	end
	
000000001DDD0111 ld_ext_p
	local tmp 32
	lsr p 16 tmp
	meta src tmp
	svp_write_ext D
	switch D
	case 7
	dis "ld al, p"
	
	default
	dis "ld %s, p" external.D
	end
	
	
000000001DDD1SSS ld_ext_ext
	svp_read_ext S
	meta src val
	svp_write_ext D
	switch D
	case 7
	dis "ld al, %s" src
	default
	dis "ld %s, %s" external.D src
	end
	
0000001B0DDDMMPP ld_int_ram
	svp_ram_read M B P
	dis "ld %s, (%s%s)" internal.D reg modestr
	mov val internal.D
	
0000001B0011MMPP ld_a_ram
	svp_ram_read M B P
	dis "ld a, (%s%s)" reg modestr
	local tmp 32
	lsl val 16 tmp
	and 0xFFFF a a
	or tmp a a
	
0000001B0111MMPP ld_p_ram
	svp_ram_read M B P
	dis "ld p, (%s%s)" reg modestr
	local tmp 32
	lsl val 16 tmp
	and 0xFFFF p p
	or tmp p p
	
0000001B0101MMPP ld_st_ram
	svp_ram_read M B P
	dis "ld st, (%s%s)" reg modestr
	svp_push val
	
0100100FCCCC0000 call_cond
	svp_check_cond F C
	svp_op_fetch
	switch istrue
	case 0
	
	default
	svp_push pc
	mov scratch1 pc
	end
	
0100110FCCCC0000 bra_cond
	svp_check_cond F C
	svp_op_fetch
	switch istrue
	case 0
	
	default
	mov scratch1 pc
	end

svp_op_fetch
	cycles 1
	cmp 1024 pc
	
	if >=U
	mov pc scratch1
	add scratch1 scratch1 scratch1
	ocall read_16
	
	else
	mov iram.pc scratch1
	end
	add 1 pc pc
	
svp_run_op
	svp_op_fetch
	dispatch scratch1