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

[Michael Spencer via Phabricator via llvm-commits]

Bigcheese added inline comments.


================
Comment at: ELF/CallGraphSort.cpp:56
+namespace {
+using SectionIndex = int32_t;
+using EdgeIndex = int32_t;
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espindola wrote:
> Delete these typedefs and just use the proper type directly.
> 
That would significantly reduce code clarity.  It's not uncommon in LLVM to do this.  LLD even has a case of this with Relocations.h RelType.


================
Comment at: ELF/Driver.cpp:602
+    uint64_t &C = Config->CallGraphProfile[std::make_pair(FromSym, ToSym)];
+    C = SaturatingAdd(C, Count);
+  }
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espindola wrote:
> This means that we supports having duplicated symbol edges. Is there a reason for that? If not please change this to report an error on duplicated edges.
> 
This makes it easier to create input.  For instance you can cat together profiles from different runs.


https://reviews.llvm.org/D36351