Re: X /[ex] 4 < Y /[ex] 4

[Jeff Law <law at redhat dot com>]

On 04/24/2017 12:24 AM, Marc Glisse wrote:
> Hello,
>
> we were missing this simplification on comparisons. Note that the testcase
> still does not simplify as much as one might like, we don't turn x+z<y+z
> into x<y. I'll try to add that next, but the interaction with
> Wstrict-overflow may be painful... The goal is that comparing size and
> capacity of a std::vector should turn into a simple comparison of the end
> pointers.
I'm all for improving our ability to analyze and generate good code for 
std::vector.  So any steps you take in this space are greatly appreciated.

Martin Sebor was considering looking at a variety of issues affecting 
our ability to do a good job with std::vector.  You might want to 
coordinate with him to make sure y'all don't duplicate work.

jeff