[llvm-commits] [llvm] r47007 - in /llvm/trunk: lib/Analysis/ScalarEvolution.cpp test/Analysis/ScalarEvolution/2008-02-12-SMAXTripCount.ll

[Chris Lattner]

On Feb 12, 2008, at 7:09 AM, Wojciech Matyjewicz wrote:

> Author: wmat
> Date: Tue Feb 12 09:09:36 2008
> New Revision: 47007
>
> URL: http://llvm.org/viewvc/llvm-project?rev=47007&view=rev
> Log:
> Fix PR2002. Suppose n is the initial value for the induction
> variable (with step 1) and m is its final value. Then, the correct  
> trip
> count is SMAX(m,n)-n. Previously, we used SMAX(0,m-n), but m-n may
> overflow and can't in general be interpreted as signed.

Very nice,  please add a comment above the code explaining what is  
going on though :)

-Chris