[PATCH] Use direct computation to calculate fallthrough edge count.

This patch uses direct computation (instead of indirect minus computation) to calculate fallthrough edge's count and frequency. This is less error-prone when the profile is inconsistent (e.g. all succ edge counts sums larger than bb count). Bootstrapped and regression test on-going. OK for trunk

Re: [PATCH] Use direct computation to calculate fallthrough edge count.

> This patch uses direct computation (instead of indirect minus > computation) to calculate fallthrough edge's count and frequency. This > is less error-prone when the profile is inconsistent (e.g. all succ > edge counts sums larger than bb count). > > Bootstrapped and regression test on-going. >