[PATCH] D36351: [lld][ELF] Add profile guided section layout

[Rafael Avila de Espindola via llvm-commits]

Michael Spencer <bigcheesegs at gmail.com> writes:

>> And you should be able to reproduce the non determinism.
>>
>
> Looking into this.

Thanks.

>> Another thing I noticed that the vertices of hottest edge in the
>> callgrpah is not close to each other in the output:
>>
>>   1026: 00000000017c3770   246 FUNC    LOCAL  DEFAULT    9 _
>> ZL15compRelocationsIN4llvm6object7ELFTypeILNS0_
>> 7support10endiannessE1ELb1EEENS1_12Elf_Rel_ImplIS5_Lb1EEEEbRKT0_SA_
>>  41309: 0000000003235e60   838 FUNC    WEAK   DEFAULT    9
>> _ZSt17__merge_sort_loopIPN4llvm6object12Elf_Rel_ImplINS1_7ELFTypeILNS0_
>> 7support10endiannessE1ELb1EEELb1EEES8_lN9__gnu_cxx5__ops15_
>> Iter_comp_iterIPFbRKS7_SD_EEEEvT_SH_T0_T1_T2_
>>
>> Cheers,
>> Rafael
>>
>
> That's because it couldn't find  _ZL15compRelocationsIN4llvm6obj
> ect7ELFTypeILNS0_7support10endiannessE1ELb1EEENS1_12Elf_Rel_ImplIS5_Lb1EEEEbRKT0_SA_
> in the symbol table as it's a local symbol.  This isn't a problem for the
> llvm based approach as it doesn't need to look up symbols.

Oops. I will fix this part tomorrow.

BTW, another thing that the patch is missing is better tests. Could you
add the example used in the paper?

Cheers,
Rafael