Ensure we differentiate between division by zero and overflow

Ensure we differentiate between division by zero and overflow

This change implements parsing of the IDIV instruction operand so that
we can find whether an integer division error was a division by zero or
an integer overflow.
It replaces the previous functionality that was implemented for OSX only
and was incomplete (it didn't handle memory operands) and partially incorrect
(not handling R8..R15 properly).