[LLVMdev] GSoC - Range Analysis

[John Regehr]

On Sat, 31 Mar 2012, John Criswell wrote:

> One thing you could do to mitigate that problem is to do an experiment
> that *shows* that your analysis has the potential to find more
> optimization opportunities than what LLVM does today.

I strongly agree.  If the analysis doesn't provide a good value 
proposition, almost nobody will care about it.

A great use case for value range analysis (that I'm personally very 
interested in) is improving the performance of codes that check for 
integer overflows:

   http://embed.cs.utah.edu/ioc/

The synergy should be obvious. To improve the performance of these codes, 
someone will need to write a pass that uses value ranges to optimize the 
LLVM intrinsics that check for math overflows.

Ideally, the overhead of overflow checking could be reduced to the point 
where some users might enable it in production codes.

John Regehr