overflows in SLDivNode

[Raffaello Giulietti]

Hi,

I'm just studying the SL implementation in the last Graal/Truffle update.

The long specialization of the division wrongly assumes that
/* No overflow is possible on a division. */

When left is Long.MIN_VALUE and right is -1 the division overflows.

OK, OK, OK, this is the only case and has a ridiculous 
(cryptography-like) probability of 2^-128 to happen randomly. And, no, 
neither java.lang.Math nor ExactMath cover this rare case of overflow.

Greetings
Raffaello