[PATCH] D157066: [clang][modules][deps] Create more efficient API for visitation of `ModuleFile` inputs

[Jan Svoboda via Phabricator via cfe-commits]

jansvoboda11 created this revision.
jansvoboda11 added a reviewer: benlangmuir.
Herald added a subscriber: ributzka.
Herald added a project: All.
jansvoboda11 requested review of this revision.
Herald added a project: clang.
Herald added a subscriber: cfe-commits.

The current `ASTReader::visitInputFiles()` function calls into `FileManager` to create `FileEntryRef` objects. This ends up being fairly costly in `clang-scan-deps`, where we mostly only care about file paths.

This patch introduces new `ASTReader` API that gives clients access to just the serialized paths. Since the scanner needs both the as-requested path and the on-disk one (and doesn't want to transform the former into the latter via `FileManager`), this patch starts serializing both of them into the PCM file if they differ.

This increases the size of scanning PCMs by 0.1% and speeds up scanning by 5%.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D157066

Files:
  clang/include/clang/Serialization/ASTBitCodes.h
  clang/include/clang/Serialization/ASTReader.h
  clang/include/clang/Serialization/ModuleFile.h
  clang/lib/Serialization/ASTReader.cpp
  clang/lib/Serialization/ASTWriter.cpp
  clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp

-------------- next part --------------
A non-text attachment was scrubbed...
Name: D157066.547096.patch
Type: text/x-patch
Size: 9795 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/cfe-commits/attachments/20230804/6222eb32/attachment.bin>