[BOLT] Emit binary section output contents if Set

[yota9]

Summary

In golang pass we're creating 2 new sections setting output contents for
them. Emit output contents if it was set during bolt work.

Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei

[yota9]

Any comments? :)

[Amir]

Looks benign to me. Can you please add a test for it though?

[yota9]

@Amir Sorry, but as I wrote golang pass would use this functionality, currently I don't see possibility to add the test. As we've discussed I've separated some patches since golang support is quite huge patch but not everything could be tested not all together(

bolt/lib/Core/BinarySection.cpp

BinarySection::hash(const BinaryData &BD,
 
   Cache[&BD] = Hash;
 
   return Hash;
 }
 
 void BinarySection::emitAsData(MCStreamer &Streamer,
                                const Twine &SectionName) const {
-  StringRef SectionContents = getContents();
+  StringRef SectionContents =
+      OutputContents.data() ? getOutputContents() : getContents();
   MCSectionELF *ELFSection =
       BC.Ctx->getELFSection(SectionName, getELFType(), getELFFlags());
 
   Streamer.switchSection(ELFSection);
   Streamer.emitValueToAlignment(getAlign());
 
   if (BC.HasRelocations && opts::HotData && isReordered())
     Streamer.emitLabel(BC.Ctx->getOrCreateSymbol("__hot_data_start"));