Consider the following loop:
int red = ii; for (int i = 0; i < n; ++i) red = (a[i] > b[i]) ? i : red;
We can vectorize this loop if i is an increasing induction variable.
The final reduced value will be tha maximum of i that the condition
a[i] > b[i] is satisfied, or the start value ii.
This patch added new RecurKind enums - IFindLastIV and FFindLastIV.
TODOs:
- Casting increasing induction variable, like truncate, SExt.