[LLVMdev] loop strength reduction and zext/sext formulae

[Sanjoy Das]

> Adding a LSRInstance::GenerateZexts modeled after
> LSRInstance::GenerateTruncates seems to fix the issue.  Does this
> makes sense or am I missing something?

Correction -- the version of LSRInstance::GenerateZexts I implemented
is buggy and it does not fix the issue.  Implementing
LSRInstance::GenerateZexts may still be the right solution, but I've
not managed to do that correctly so far.

-- Sanjoy

>
> -- Sanjoy