[PATCH] D150292: [clang][modules] Serialize `Module::DefinitionLoc`

[Jan Svoboda via Phabricator via cfe-commits]

jansvoboda11 created this revision.
jansvoboda11 added reviewers: benlangmuir, Bigcheese.
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.

This is a prep patch for avoiding the quadratic number of calls to `HeaderSearch::lookupModule()` in `ASTReader` for each (transitively) loaded PCM file. (Specifically in the context of `clang-scan-deps`).

This patch explicitly serializes `Module::DefinitionLoc` so that we can stop relying on it being filled by the module map parser. This change also required change to the module map parser, where we used the absence of `DefinitionLoc` to determine whether a file came from a PCM file. We also need to make sure we consider the "containing" module map affecting when writing a PCM, so that it's not stripped during serialization, which ensures `DefinitionLoc` still ends up pointing to the correct offset. This is intended to be a NFC change.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D150292

Files:
  clang/include/clang/Serialization/ASTBitCodes.h
  clang/lib/Lex/ModuleMap.cpp
  clang/lib/Serialization/ASTReader.cpp
  clang/lib/Serialization/ASTWriter.cpp

-------------- next part --------------
A non-text attachment was scrubbed...
Name: D150292.521077.patch
Type: text/x-patch
Size: 6698 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/cfe-commits/attachments/20230510/e4a92a06/attachment.bin>