ideas.txt

Ideas for the SISA64 architecture:

1) Multithreading

	Implement multithreading by allowing dwrite() to access mutexes and make separate executions of emulate_sisa64() on some fixed number of alternate threads.

2) Tube instructions- linear execution of micro-ops. Tried and it didn't speed things up.

	(CANCELLEED)

3) SIMD ops
	Allow for simd operations within the gpregs. They take aligned gpreg ids, I.E., a V4 is aligned to 4, so the gpreg id's bottom 2 bits are empty.
	V2 is aligned to 2, so the gpreg id's bttom bit is empty.

	iv2add
	iv2sub
	iv2mul

	iv4add
	iv4sub
	iv4mul

	fv2add
	fv2sub
	fv2mul

	dv2add
	dv2sub
	dv2mul
	
	fv4add
	fv4sub
	fv4mul

	dv4add
	dv4sub
	dv4mul
	
	(CANCELLED)
		
4) Stack-relative loads and stores - IMPLEMENTED
	Allow for reads and writes relative to the stack pointer, using fixed offsets.

	ldspXX regid, offset
	stspXX regid, offset

5) bswap instructions - IMPLEMENTED

	bswap64 rid
	bswap32 rid
	bswap16 rid

6) mnz instruction- move if not zero. - IMPLEMENTED

	mnz rid_test, rid_dest, rid_src

7) Scopes and Local variables. - IMPLEMENTED

I would like to implement scopes in SISA64, with local variables that are register allocated.

Basically, all scope variables are registers. Their names with a dollar sign in front of them

are their register IDs.

I can implement structs and arrays by having a stack allocation and having a pointer to the object

stored in a register, whose register ID is the variable's name in the assembly language.

myFunction:
//the following line modifies scope state internally.
//I've decided that I will not make it allocate anything on the stack.
//So it should be really easy to generate.

//the format of a scope start is requires a pair of parentheses,
//with an optional comma-separated list of variable definitions.
//Then a return value.

${(u64 a, u64 b) -> u64:\
		u64 c; 			\//2
		f64 mydouble;	\//3
		u64 i;			\//4
		u64 tmp1;		\//5
	
	mov $c, $a; //translates to mov 2, 0;
	iadd $c, $b; //translates to iadd 2, 1;

	$return $c; //translates to mov 0, 2;
	


$} //end scope