Provide better -O0 assembly on request

[Sergey Dmitrouk]

On Tue, May 19, 2015 at 04:03:52PM -0700, Robinson, Paul wrote:
>    I thought Sergey wanted to have a go at it first...  but if not, I'll need
>    to wrap up some release-related activities first before I try it.
> 
>    --paulr

Yep, the patch should be up for review soon, I'll CC everyone from this
thread.  Inserting local values around first use turned out to be more
complicated as FastISel implementation relies on current constant
placement in several places and I'm not sure how to rewrite those parts.

-- 
Sergey