1 files changed, 78 insertions, 0 deletions
diff --git a/clang/lib/Serialization/GeneratePCH.cpp b/clang/lib/Serialization/GeneratePCH.cpp
new file mode 100644
index 000000000000..002233e49bb0
--- /dev/null
+++ b/clang/lib/Serialization/GeneratePCH.cpp
@@ -0,0 +1,78 @@
+//===--- GeneratePCH.cpp - Sema Consumer for PCH Generation -----*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file defines the PCHGenerator, which as a SemaConsumer that generates
+//  a PCH file.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/AST/ASTContext.h"
+#include "clang/Lex/HeaderSearch.h"
+#include "clang/Lex/Preprocessor.h"
+#include "clang/Sema/SemaConsumer.h"
+#include "clang/Serialization/ASTWriter.h"
+#include "llvm/Bitstream/BitstreamWriter.h"
+
+using namespace clang;
+
+PCHGenerator::PCHGenerator(
+    const Preprocessor &PP, InMemoryModuleCache &ModuleCache,
+    StringRef OutputFile, StringRef isysroot, std::shared_ptr<PCHBuffer> Buffer,
+    ArrayRef<std::shared_ptr<ModuleFileExtension>> Extensions,
+    bool AllowASTWithErrors, bool IncludeTimestamps,
+    bool ShouldCacheASTInMemory)
+    : PP(PP), OutputFile(OutputFile), isysroot(isysroot.str()),
+      SemaPtr(nullptr), Buffer(std::move(Buffer)), Stream(this->Buffer->Data),
+      Writer(Stream, this->Buffer->Data, ModuleCache, Extensions,
+             IncludeTimestamps),
+      AllowASTWithErrors(AllowASTWithErrors),
+      ShouldCacheASTInMemory(ShouldCacheASTInMemory) {
+  this->Buffer->IsComplete = false;
+}
+
+PCHGenerator::~PCHGenerator() {
+}
+
+void PCHGenerator::HandleTranslationUnit(ASTContext &Ctx) {
+  // Don't create a PCH if there were fatal failures during module loading.
+  if (PP.getModuleLoader().HadFatalFailure)
+    return;
+
+  bool hasErrors = PP.getDiagnostics().hasErrorOccurred();
+  if (hasErrors && !AllowASTWithErrors)
+    return;
+
+  Module *Module = nullptr;
+  if (PP.getLangOpts().isCompilingModule()) {
+    Module = PP.getHeaderSearchInfo().lookupModule(
+        PP.getLangOpts().CurrentModule, /*AllowSearch*/ false);
+    if (!Module) {
+      assert(hasErrors && "emitting module but current module doesn't exist");
+      return;
+    }
+  }
+
+  // Emit the PCH file to the Buffer.
+  assert(SemaPtr && "No Sema?");
+  Buffer->Signature =
+      Writer.WriteAST(*SemaPtr, OutputFile, Module, isysroot,
+                      // For serialization we are lenient if the errors were
+                      // only warn-as-error kind.
+                      PP.getDiagnostics().hasUncompilableErrorOccurred(),
+                      ShouldCacheASTInMemory);
+
+  Buffer->IsComplete = true;
+}
+
+ASTMutationListener *PCHGenerator::GetASTMutationListener() {
+  return &Writer;
+}
+
+ASTDeserializationListener *PCHGenerator::GetASTDeserializationListener() {
+  return &Writer;
+}