organization of optimization options in manual

[Joel Sherrill]

On January 17, 2015 8:34:04 AM CST, Gary Funck <gary@intrepid.com> wrote:
>On 01/14/15 23:15:59, Jeff Law wrote:
>> Sounds good.  I think just starting with the list & creating the
>buckets
>> with the list.  Then post here and we'll iterate and try to nail that
>down
>> before you start moving everything in the .texi file.
>
>Something to consider, if the optimization options are re-worked:
>Arrange the -O options such that -O1 can be described by a
>distinct set of specific optimizations enabled (or disabled)
>in addition to -O0, and -O2 would be described as a composite
>of specific optimizations applied to -O1 and so on. (This
>might require the addition of new optimization options.)
>
>For completeness, if a specific optimization requires
>certain passes or the assertion of other options, that should
>somehow be encoded internally within the compiler.
>
>This would potentially make it easier to find which optimization
>(or pass) is causing a regression and might make it easier
>for users to understand the exact effect of a particular -O option.

Make sure whatever pattern is followed for optimizations is followed for warnings. It is nice to know when adding an option actually is needed.

>- Gary

--joel