[PATCH] D156611: [llvm-cov] Fix a bug about using `convert-for-testing` on multi-source object files

[Yuhao Gu via Phabricator via llvm-commits]

AtomicGu marked 2 inline comments as done.
AtomicGu added inline comments.


================
Comment at: llvm/lib/ProfileData/Coverage/CoverageMappingReader.cpp:908-910
-    uint32_t FilenamesSize =
-        CovHeader->getFilenamesSize<support::endianness::little>();
-    uint32_t CoverageMappingSize = sizeof(CovMapHeader) + FilenamesSize;
----------------
phosek wrote:
> It looks like in the current implementation, we're using `getFilenameSize` to compute the `CoverageMappingSize`, but `CovMapHeader` also contains `CoverageMappingSize`, accessible through `getCoverageSize()`. Shouldn't we be using that instead? Isn't that the issue with the current implementation?
I have inspected this variable. The value is not right. It is always zero, as the documentation says:

> The length of the string in the third field of __llvm_coverage_mapping that contains any encoded coverage mapping data affixed to the coverage header. Always 0, but present for backwards compatibility.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D156611/new/

https://reviews.llvm.org/D156611