memset-alignment.bt

kprobe:__memset
{
	@total = count();

	if (reg("si") != 0) {
		return;
	}

	@zero = count();
	
	if (reg("dx") < 64) {
		@too_small = count();
		return;
	}

	$i = 0x800000000000000;
	while ($i > 0) {
		if (!(reg("di") & ($i - 1))) {
			@alignment = hist($i);
			if ($i >= 64) {
				@aligned64 = count();
			}
			break;
		}
		$i >>= 1;
	}
}

interval:s:3
{
	print(@total);
	print(@zero);
	print(@too_small);
	print(@aligned64);
	print(@alignment);
}

memset.bt

kprobe:__memset
{
	@total = count();

	if (reg("si") != 0) {
		return;
	}

	@zero = count();

	if (!(reg("di") & 63) && reg("dx") >= 64) {
		@aligned = count();
	} else if (reg("dx") >= 127) {
		@unaligned = count();
	} else {
		@too_small = count();
	}
}

interval:s:3
{
	print(@total);
	print(@zero);
	print(@aligned);
	print(@unaligned);
	print(@too_small);
}