[all-commits] [llvm/llvm-project] 920806: [clang][deps] Store common, partially-formed invoc...

[Jan Svoboda via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 9208065a7b51958b44ea012259097e742825b7f4
      https://github.com/llvm/llvm-project/commit/9208065a7b51958b44ea012259097e742825b7f4
  Author: Jan Svoboda <jan_svoboda at apple.com>
  Date:   2023-09-07 (Thu, 07 Sep 2023)

  Changed paths:
    M clang/include/clang/Tooling/DependencyScanning/ModuleDepCollector.h
    M clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp

  Log Message:
  -----------
  [clang][deps] Store common, partially-formed invocation (#65677)

We create one `CompilerInvocation` for each modular dependency we
discover. This means we create a lot of copies, even though most of the
invocation is the same between modules. This patch makes use of the
copy-on-write flavor of `CompilerInvocation` to share the common parts,
reducing memory usage and speeding up the scan.