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Subject: Re: [9front] make arrays big: qsort edition
Reply-To: 9front@9front.org
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Quoth Nick Owens <mischief@offblast.org>:
> are you able to test this change with a very large array?

Yes, but not easily. This is work towards
fixing that.

Here's a program that creates a large array
using brk.

#include <u.h>
#include <libc.h>

extern char end[];
usize sorted;

int
intcmp(void *a, void *b)
{
	sorted++;
	return *(int*)b-*(int*)a;
}

void
main(int argc, char **argv)
{
	usize n;
	int *p;

	n = 8ULL*1024*1024*1024;
	if(brk(end + sizeof(int)*n) == -1)
		sysfatal("brk: %r");
	p = (void*)end;
	qsort(p, n, sizeof(int), intcmp);
	fprint(2, "%zd\n", sorted);
}