Fix float4/8 to handle Infinity and Nan consistently, e.g. Infinity is a

valid result from a computation if one of the input values was infinity.
The previous code assumed an operation that returned infinity was an
overflow.

Handle underflow/overflow consistently, and add checks for aggregate
overflow.

Consistently prevent Inf/Nan from being cast to integer data types.

Fix INT_MIN % -1 to prevent overflow.

Update regression results for new error text.

Per report from Roman Kononov.