Bit subscriptions, RAM columnwise layouts

[BCS]

Reply to Benjamin,

> Reply to bearophile,
> 
>> So today the caches have changed a little how optimal code has to be
>> written in C. The authors say that a downside of C is that it forces
>> the programmer to do such memory layout manually, and today this may
>> lead to less performance.
>> 
> Darn you, now I'm going to need to wright a column struct array
> template that takes a struct and stripes the columns.
> 
> OTOH this is going to be fun...
> 

Done:

http://www.dsource.org/projects/scrapple/browser/trunk/columns/columns.d

not to fancy but supports code like this:

struct Foo
{
	float k;
	int i;
	uint j;
	void print(){writef("%s, %s, %s\n", k, i, j);}
}

Foo foo;
Columns!(Foo) FooCol;

FooCol.length = 10;
for(int i = 0; i < 10; i++)
{
	foo.k = 3.14 * i;
	foo.i = -3 - i;
	FooCol[i] = foo;
	FooCol[i].j = 5 + i;
}
foreach(float f; FooCol.k) writef("%s ", f); writef(\n);
foreach(int   i; FooCol.i) writef("%s ", i); writef(\n);
foreach(uint  u; FooCol.j) writef("%s ", u); writef(\n);
FooCol[3].FullItem.print();