OP_IF_FALSE_JUMP

[Ratstail91]

A funny thing about if-else, while and for - they can all be coded using an opcode called OP_IF_FALSE_JUMP - but in some cases, a simple OP_JUMP can suffice.

In both cases, the labels could be relative to the code-section start in the compiler, or they could be relative to their own positions - I'm not sure which is a better fit, but I'm leaning towards the latter. I think an integer value for the jump distance is required.

Here's some scratches I dug up and cleaned up.

if:

*evaluate condition*
OP_IF_FALSE_JUMP end
{
	*evaluate then path*
}
end:

if, else:

*evaluate condition*
OP_IF_FALSE_JUMP else
{
	*evaluate then path*
}
OP_LITERAL false
OP_IF_FALSE_JUMP end
else:
{
	*evaluate else path*
}
end:

while:

begin:
*evaluate expression*
OP_IF_FALSE_JUMP end
{
	*evaluate body*
}
OP_LITERAL false
OP_IF_FALSE_JUMP begin
end:

for:

{
	*evaluate first clause*
	begin:
	*evaluate second clause*
	OP_IF_FALSE_JUMP end
	{
		*evaluate body*
	}
	{
		*evaluate third clause*
	}
	OP_LITERAL false
	OP_IF_FALSE_JUMP begin
	end:
}