[llvm-commits] [PATCH] Multidimensional Array Index Delinearization Analysis

[Sameer Sahasrabuddhe]

On Thu, 27 Sep 2012 12:11:32 +0200
Tobias Grosser <tobias at grosser.es> wrote:

> It seems we would need to mirror a lot of pattern matching from 
> ScalarEvolution. Working directly on SCEVs could avoid this.

Currently, it's easy to confuse the delinearizer by computing two copies
of the same value in the code, because the polynomials are neither
uniq'ed nor canonicalized. It is not desirable to assume that the input
code will be optimized before being delinearized ... premature scalar
optimizations might break Polly, for example.

The SCEV infrastructure seems ideal to resolve this. But I have not
grokked SCEV's sufficiently yet to see the pros and cons of
implementing the delinearizer on Value's v/s SCEVs.

Sameer.