[PATCH] D155733: [lld-macho] Change UUID calculation to use constant chunk count

[Keith Smiley via Phabricator via llvm-commits]

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Using the current machine's thread count as the chunkCount results in
non-deterministic binaries across machines with different core counts.
This is an attempt to pick a relatively reasoanble number for the
average case. Theoretically this could be configurable.

Fixes: https://github.com/llvm/llvm-project/issues/63961


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D155733

Files:
  lld/MachO/Writer.cpp


Index: lld/MachO/Writer.cpp
===================================================================
--- lld/MachO/Writer.cpp
+++ lld/MachO/Writer.cpp
@@ -1180,7 +1180,7 @@
   TimeTraceScope timeScope("Computing UUID");
 
   ArrayRef<uint8_t> data{buffer->getBufferStart(), buffer->getBufferEnd()};
-  unsigned chunkCount = parallel::strategy.compute_thread_count() * 10;
+  unsigned chunkCount = 100;
   // Round-up integer division
   size_t chunkSize = (data.size() + chunkCount - 1) / chunkCount;
   std::vector<ArrayRef<uint8_t>> chunks = split(data, chunkSize);


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