[LLVMdev] RFH: passing options from clang down to opt

[Eric Christopher]

On Tue, Oct 1, 2013 at 4:51 PM, Diego Novillo <dnovillo at google.com> wrote:
> On Tue, Oct 1, 2013 at 3:53 PM, Rafael Espíndola
> <rafael.espindola at gmail.com> wrote:
>> The option handling in clang in fairly different from opt. The comment
>> about the mixed name was just a guess as to why you don't see the
>> driver passing it down to -cc1.
>
> Clang::ConstructJob is ~2k lines long.  I was putting the handling of
> this option too far down.  I moved it up and it's now being passed.
> Not sure what order needs to be kept in this function, however.
>
>> Once that is working, you will probably need to:
>>
>> * Patch ParseCodeGenArgs to record the option
>> * Patch EmitAssemblyHelper::CreatePasses to set the option to enable
>> the  pass in the pass manager (assuming that is the effect you want).
>
> Thanks.  That was my disconnect.  I was confusing 'opt' with clang's backend.
>
> The attached patch does what I want.  Does it look like it's in the
> right direction?
>

Seems pretty reasonable.

-eric