Operations inside of loops widens type of unrelated variable used in conditional statement #12666

Bug report

It seems like modifying a variable inside of a loop where the conditional compares said variable to another variable sometimes widens the type of the other variable.

As an example, here the type of $xn is widened int after the loop. If the increment is changed to 1, $xn stay an int<1,max> however.

**
 * @param int<1,max> $x0
 * @param int<1,max> $xn
 */
function addFrac(int $x0, int $xn): float
{
	$xi = $x0;

	\PHPStan\dumpType($xn);

	while ($xi < $xn) {
		$xi += 0.1;
	}

	\PHPStan\dumpType($xn);

	return $xi;
}

Code snippet that reproduces the problem

https://phpstan.org/r/0bf36f1f-55eb-4378-8fcb-a5a7d1648ef2

Expected output

I'd expect the type of $xn to either remain the same or narrow.

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