[clang] [C++20] [Modules] Embed all source files for C++20 Modules (PR #102444)

[Chuanqi Xu via cfe-commits]

https://github.com/ChuanqiXu9 updated https://github.com/llvm/llvm-project/pull/102444

>From 71e93c68dd186d70f2c922963897ffb1dce70179 Mon Sep 17 00:00:00 2001
From: Chuanqi Xu <yedeng.yd at linux.alibaba.com>
Date: Thu, 8 Aug 2024 15:30:35 +0800
Subject: [PATCH] [C++20] [Modules] Embed all source files for C++20 Modules

---
 clang/include/clang/CodeGen/CodeGenAction.h    |  2 +-
 clang/include/clang/Frontend/FrontendActions.h |  4 +++-
 clang/include/clang/Serialization/ModuleFile.h | 10 +++++-----
 clang/lib/CodeGen/CodeGenAction.cpp            |  5 +++--
 clang/lib/Frontend/FrontendActions.cpp         | 15 ++++++++++++---
 5 files changed, 24 insertions(+), 12 deletions(-)

diff --git a/clang/include/clang/CodeGen/CodeGenAction.h b/clang/include/clang/CodeGen/CodeGenAction.h
index 186dbb43f01ef7..461450d875ec50 100644
--- a/clang/include/clang/CodeGen/CodeGenAction.h
+++ b/clang/include/clang/CodeGen/CodeGenAction.h
@@ -57,7 +57,7 @@ class CodeGenAction : public ASTFrontendAction {
   bool loadLinkModules(CompilerInstance &CI);
 
 protected:
-  bool BeginSourceFileAction(CompilerInstance &CI) override;
+  bool BeginInvocation(CompilerInstance &CI) override;
 
   /// Create a new code generation action.  If the optional \p _VMContext
   /// parameter is supplied, the action uses it without taking ownership,
diff --git a/clang/include/clang/Frontend/FrontendActions.h b/clang/include/clang/Frontend/FrontendActions.h
index a620ddfc40447d..e82f15f89b6432 100644
--- a/clang/include/clang/Frontend/FrontendActions.h
+++ b/clang/include/clang/Frontend/FrontendActions.h
@@ -152,11 +152,13 @@ class GenerateModuleFromModuleMapAction : public GenerateModuleAction {
   CreateOutputFile(CompilerInstance &CI, StringRef InFile) override;
 };
 
+bool BeginInvocationForModules(CompilerInstance &CI);
+
 /// Generates full BMI (which contains full information to generate the object
 /// files) for C++20 Named Modules.
 class GenerateModuleInterfaceAction : public GenerateModuleAction {
 protected:
-  bool BeginSourceFileAction(CompilerInstance &CI) override;
+  bool BeginInvocation(CompilerInstance &CI) override;
 
   std::unique_ptr<ASTConsumer> CreateASTConsumer(CompilerInstance &CI,
                                                  StringRef InFile) override;
diff --git a/clang/include/clang/Serialization/ModuleFile.h b/clang/include/clang/Serialization/ModuleFile.h
index 3e920c0f683601..30e7f6b3e57bd8 100644
--- a/clang/include/clang/Serialization/ModuleFile.h
+++ b/clang/include/clang/Serialization/ModuleFile.h
@@ -88,13 +88,13 @@ class InputFile {
 
   InputFile(FileEntryRef File, bool isOverridden = false,
             bool isOutOfDate = false) {
-    assert(!(isOverridden && isOutOfDate) &&
-           "an overridden cannot be out-of-date");
     unsigned intVal = 0;
-    if (isOverridden)
-      intVal = Overridden;
-    else if (isOutOfDate)
+    // Make isOutOfDate with higher priority than isOverridden.
+    // It is possible if the recorded hash value mismatches.
+    if (isOutOfDate)
       intVal = OutOfDate;
+    else if (isOverridden)
+      intVal = Overridden;
     Val.setPointerAndInt(&File.getMapEntry(), intVal);
   }
 
diff --git a/clang/lib/CodeGen/CodeGenAction.cpp b/clang/lib/CodeGen/CodeGenAction.cpp
index e87226e60297c0..8900faf07eeafe 100644
--- a/clang/lib/CodeGen/CodeGenAction.cpp
+++ b/clang/lib/CodeGen/CodeGenAction.cpp
@@ -969,9 +969,10 @@ CodeGenerator *CodeGenAction::getCodeGenerator() const {
   return BEConsumer->getCodeGenerator();
 }
 
-bool CodeGenAction::BeginSourceFileAction(CompilerInstance &CI) {
+bool CodeGenAction::BeginInvocation(CompilerInstance &CI) {
   if (CI.getFrontendOpts().GenReducedBMI)
-    CI.getLangOpts().setCompilingModule(LangOptions::CMK_ModuleInterface);
+    return BeginInvocationForModules(CI);
+
   return true;
 }
 
diff --git a/clang/lib/Frontend/FrontendActions.cpp b/clang/lib/Frontend/FrontendActions.cpp
index e70210d55fe28d..7758746f9a4837 100644
--- a/clang/lib/Frontend/FrontendActions.cpp
+++ b/clang/lib/Frontend/FrontendActions.cpp
@@ -262,11 +262,20 @@ GenerateModuleFromModuleMapAction::CreateOutputFile(CompilerInstance &CI,
                                     /*ForceUseTemporary=*/true);
 }
 
-bool GenerateModuleInterfaceAction::BeginSourceFileAction(
-    CompilerInstance &CI) {
+bool clang::BeginInvocationForModules(CompilerInstance &CI) {
+  // Embed all module files for named modules.
+  // See https://github.com/llvm/llvm-project/issues/72383 for discussion.
+  CI.getFrontendOpts().ModulesEmbedAllFiles = true;
   CI.getLangOpts().setCompilingModule(LangOptions::CMK_ModuleInterface);
+  return true;
+}
 
-  return GenerateModuleAction::BeginSourceFileAction(CI);
+bool GenerateModuleInterfaceAction::BeginInvocation(
+    CompilerInstance &CI) {
+  if (!BeginInvocationForModules(CI))
+    return false;
+
+  return GenerateModuleAction::BeginInvocation(CI);
 }
 
 std::unique_ptr<ASTConsumer>