[PATCH] D86905: Flush bitcode incrementally for LTO output

[stephan.yichao.zhao via Phabricator via llvm-commits]

stephan.yichao.zhao marked 3 inline comments as done.
stephan.yichao.zhao added inline comments.


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Comment at: lld/ELF/LTO.cpp:169
+              openLTOOutputFile(config->outputFile))
+        WriteBitcodeToFile(m, *os, false, nullptr, false, nullptr,
+                           config->emitLLVMFlushThreshold);
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tejohnson wrote:
> Nit, document constant parameters with /*parameter_name=*/
reverted the change at lld options.


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Comment at: llvm/include/llvm/Bitstream/BitstreamWriter.h:96
+  void FlushToFile() {
+    constexpr uint64_t FlushThreshold = 1UL << 29; // 512M
+    if (!FS) {
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tejohnson wrote:
> stephan.yichao.zhao wrote:
> > tejohnson wrote:
> > > Would it be valuable to make this configurable? How sensitive is performance to the value chosen here?
> > Added a flag to plugin-opt.  Is it the right way to do this?
> Oh sorry, I just meant an llvm internal option (cl::opt<int>) in this file. Will let @MaskRay comment on whether they want it as an lld option. 
Switched to cl::opt. Thank you for the suggestion, I did not know this option.

What is the proper way to call the options with clang or lld? For example, I tried clang/ld.lld with --bitcode-mdindex-threshold=1 or -bitcode-mdindex-threshold=1. They are not accepted. Do we need any prefix before them?


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D86905/new/

https://reviews.llvm.org/D86905