[PATCH] D27768: COFF: Open and map input files asynchronously on Windows.

[Rui Ueyama via Phabricator via llvm-commits]

ruiu added a comment.

Which is actually slow, open or mmap? My wild guess is that mmap is slow. If so, can we open a file to get an error early and then mmap? It will simplify std::future<MBErrPair> to std::future<MemoryBuffer>.



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Comment at: lld/COFF/Driver.cpp:794
   Symtab.addCombinedLTOObjects();
+  run();
 
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Is this enough to run this only once? In the above code we repeat until converge.


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Comment at: lld/COFF/InputFiles.h:86
 
   // Returns an input file for a given symbol. A null pointer is returned if we
   // have already returned the same input file. (So that we don't instantiate
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Update comment.


https://reviews.llvm.org/D27768