[LLVMdev] -Os

reed kotler rkotler at mips.com
Tue Jul 23 05:22:07 PDT 2013

On 07/23/2013 05:19 AM, Konstantin Tokarev wrote:
> 23.07.2013, 16:05, "reed kotler" <rkotler at mips.com>:
>> When I use -Os with a clang that implicitly calls llc, I get much
>> different code than when call clang first with -Os and then call llc.
> clang does NOT call llc internally.
I understand. It's invoking that functionality is what I meant to say 
but not technically
running that command.
>> How do I get these two paths to generate the same code?
> Call llc with -Os?
You can't pass -Os to llc.

-Os is a clang only option. It's reflected in the IR used by llc in the 
function attributes.

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