[llvm-commits] [llvm-gcc-4.2] r49253 - /llvm-gcc-4.2/trunk/gcc/llvm-backend.cpp

[Chris Lattner]

On Apr 6, 2008, at 11:58 AM, Duncan Sands wrote:

> Hi Chris,
>
>>        -funwind-tables
>>            Similar to -fexceptions, except that it will just generate
>> any needed static data, but will
>>            not affect the generated code in any other way.  You will
>> normally not enable this option;
>>            instead, a language processor that needs this handling
>> would enable it on your behalf.
>>
>>>
>>> Out of curiosity, what kind of "something else" might this be?
>>
>> Some people want "unwind info no matter what".  For example, some
>> performance tools want to be able to walk the stack etc with unwind
>> info.  I don't think our current nounwind bit is sufficient to model
>> this though, and I don't thank that overloading it to do so is a good
>> thing.
>
> it sounds like -funwind-tables has no semantic effect so how about
> making it an llc parameter?

That would be fine with me, or it could be another param attr.

> Another possibility is to output some debug intrinsic into functions.

ick, I'd prefer an attribute over this :)

-Chris