yaglitch/yaglitch_op.asm

OP:
	.numeric:
		; rdi contain the number
		shr rdi, 32
	._push:
		; push rdi (edi) on stack_buff
		mov eax, edi
		xor rbx, rbx
		mov ebx, [tosp]
		add ebx, 4
		cmp ebx, STACK_SZ * 4
		jl .go_push
		mov ebx, 0
		.go_push:
			mov [tosp], ebx
			lea rdi, [stack_buff+rbx]
			stosd
		ret

	.drop: ; drop just calls pop
	._pop:
		; pop eax from stack_buff
		xor rbx, rbx
		mov ebx, [tosp]
		lea rsi, [stack_buff+rbx]
		xor rax, rax
		lodsd
		test ebx, ebx
		jz .pop_no_dec
		sub ebx, 4
		jmp .pop_end
		.pop_no_dec:
			mov ebx, (STACK_SZ-1) * 4
		.pop_end:
			mov [tosp], ebx
		ret


	.t: ; push t on the stack
		mov edi, [t]
		call ._push
		ret

	.put:
		pushf
		cld
		xor rbx, rbx
		xor rax, rax
		mov ebx, [tosp]
		lea rsi, [stack_buff+rbx]
		lodsd
		and eax, 0xFF
		inc eax
		mov edx, eax
		lodsd
		neg rdx
		lea rdi, [stack_buff + rdx]
		stosq
		call OP._pop
		popf
		ret
	.mul:
		call .prep_2arg
		mul ebx
		mov edi, eax
		call OP._push
		ret
	.div:
		call .prep_2arg
		test ebx, ebx
		jz .nodiv
		xor rdx, rdx
		div ebx
		jmp .divend
		.nodiv:
		xor eax, eax
		.divend:
		mov edi, eax
		call OP._push
		ret
	.add:
		call .prep_2arg
		add eax, ebx
		mov edi, eax
		call OP._push
		ret
	.sub:
		call .prep_2arg
		sub eax, ebx
		mov edi, eax
		call OP._push
		ret
	.mod:
		call .prep_2arg
		test rbx, rbx
		jz .nomod
		xor edx, edx
		div ebx
		jmp .endmod
		.nomod:
		xor edx, edx
		.endmod:
		mov edi, edx
		call OP._push
		ret
	.lshift:
		call OP._pop
		push rax
		call OP._pop
		pop rcx
		shl eax, cl
		mov edi, eax
		call OP._push
		ret
	.rshift:
		call OP._pop
		push rax
		call OP._pop
		pop rcx
		shr eax, cl
		mov edi, eax
		call OP._push
		ret
	.and:
		call .prep_2arg
		and eax, ebx
		mov edi, eax
		call OP._push
		ret
	.or:
		call .prep_2arg
		or eax, ebx
		mov edi, eax
		call OP._push
		ret
	.xor:
		call .prep_2arg
		xor eax, ebx
		mov edi, eax
		call OP._push
		ret
	.not:
		call OP._pop
		not eax
		mov edi, eax
		call OP._push
		ret
	.dup:
		call OP._pop
		push rax
		mov edi, eax
		call OP._push
		pop rdi
		call OP._push
		ret
	.pick:
		call OP._pop
		inc eax
		and eax, 0xFF
		mov ebx, 4
		mov ecx, [tosp]
		mul ebx ; mul by data size
		cmp eax, [tosp]
		jg .pick_loop
		sub ecx, eax
		jmp .pick_lea
		.pick_loop: ; eax > tosp
		sub eax, ecx
		mov ecx, (STACK_SZ - 1) * 4
		sub ecx, eax
		.pick_lea:
		lea rsi, [stack_buff+ecx]
		lodsd
		push rax
		call OP._pop
		pop rdi
		call OP._push
		ret


	.swap:
		call OP._pop
		push rax
		call OP._pop
		xchg rax, [rsp]
		mov edi, eax
		call OP._push
		pop rdi
		call OP._push
		ret
	.lt:
		call .prep_2arg
		xor rdi, rdi
		cmp eax, ebx
		jge .lt_false
		not rdi
		.lt_false:
		call OP._push
		ret
	.gt:
		call .prep_2arg
		xor rdi, rdi
		cmp eax, ebx
		jle .gt_false
		not rdi
		.gt_false:
		call OP._push
		ret
	.eq:
		call .prep_2arg
		xor rdi, rdi
		cmp eax, ebx
		jne .eq_false
		not rdi
		.eq_false:
		call OP._push
		ret

	.prep_2arg:
		; utils that pop both arguments V1 in eax, V2 in ebx
		call OP._pop
		push rax
		call OP._pop
		pop rbx
		ret