From b6a8fd5475014e1a00a5bf3135a5e5ef84f96af0 Mon Sep 17 00:00:00 2001
From: ykiko <ykikoykikoykiko@gmail.com>
Date: Sun, 13 Oct 2024 18:32:03 +0800
Subject: [PATCH] Basic logic for building PCM.

---
 include/Compiler/Compiler.h |  2 +-
 src/Compiler/Compiler.cpp   | 34 +++++++++++++++++--------
 tests/AST/Compiler.cpp      | 50 ++++++++++++++++++++++++++++++++++++-
 3 files changed, 74 insertions(+), 12 deletions(-)

diff --git a/include/Compiler/Compiler.h b/include/Compiler/Compiler.h
index 0af8ebf4..666051c1 100644
--- a/include/Compiler/Compiler.h
+++ b/include/Compiler/Compiler.h
@@ -34,7 +34,7 @@ public:
                   llvm::StringRef filepath);
 
     /// build PreCompiledModule.
-    void buildPCM();
+    void buildPCM(llvm::StringRef filename, llvm::StringRef content, llvm::ArrayRef<const char*> args);
 
     /// build AST.
     void buildAST();
diff --git a/src/Compiler/Compiler.cpp b/src/Compiler/Compiler.cpp
index 49bef4d8..a79a5c0a 100644
--- a/src/Compiler/Compiler.cpp
+++ b/src/Compiler/Compiler.cpp
@@ -113,18 +113,9 @@ void Compiler::buildPCH(llvm::StringRef filename, llvm::StringRef content, llvm:
         std::terminate();
     }
 
-    instance->getASTContext().getTranslationUnitDecl()->dump();
+    // instance->getASTContext().getTranslationUnitDecl()->dump();
 
     action.EndSourceFile();
-
-    // auto err = instance->ExecuteAction(action);
-    //
-    ////
-    //
-    // if(!err) {
-    //    llvm::outs() << "Error has occured!!";
-    //    std::terminate();
-    //}
 }
 
 void Compiler::applyPCH(clang::CompilerInvocation& invocation,
@@ -146,4 +137,27 @@ void Compiler::applyPCH(clang::CompilerInvocation& invocation,
     PreprocessorOpts.UsePredefines = false;
 }
 
+void Compiler::buildPCM(llvm::StringRef filename, llvm::StringRef content, llvm::ArrayRef<const char*> args) {
+    auto invocation = createInvocation(filename, content, args);
+
+    auto instance = createInstance(std::move(invocation));
+
+    auto& frontend = instance->getFrontendOpts();
+    frontend.OutputFile = "/home/ykiko/C++/clice2/build/cache/xxx.pcm";
+
+    auto action = clang::GenerateReducedModuleInterfaceAction();
+
+    if(!action.BeginSourceFile(*instance, instance->getFrontendOpts().Inputs[0])) {
+        llvm::errs() << "Failed to begin source file\n";
+        std::terminate();
+    }
+
+    if(auto error = action.Execute()) {
+        llvm::errs() << "Failed to execute action: " << error << "\n";
+        std::terminate();
+    }
+
+    action.EndSourceFile();
+}
+
 }  // namespace clice
diff --git a/tests/AST/Compiler.cpp b/tests/AST/Compiler.cpp
index 87b27668..ceaab01d 100644
--- a/tests/AST/Compiler.cpp
+++ b/tests/AST/Compiler.cpp
@@ -29,7 +29,7 @@ TEST(clice, ModuleScanner) {
     });
 }
 
-TEST(clice, Compiler) {
+TEST(clice, PCH) {
     const char* code = R"(
 #include <cstdio>
 
@@ -69,5 +69,53 @@ int main(){
     instance->getASTContext().getTranslationUnitDecl()->dump();
 }
 
+TEST(clice, PCM) {
+    const char* mod = R"(
+export module M;
+
+export constexpr int f() {
+    return 42;
+}
+)";
+
+    const char* code = R"(
+import M;
+
+int main() {
+    constexpr int x = f();
+    return x;
+}
+)";
+
+    std::vector<const char*> compileArgs = {
+        "clang++",
+        "-std=c++20",
+        "main.cpp",
+        "-resource-dir",
+        "/home/ykiko/C++/clice2/build/lib/clang/20",
+    };
+
+    Compiler compiler;
+    compiler.buildPCM("main.cpp", mod, compileArgs);
+
+    auto invocation = createInvocation("main.cpp", code, compileArgs);
+    // compiler.applyPCH(*invocation, "main.cpp", code, "/home/ykiko/C++/clice2/build/cache/xxx.pch");
+    invocation->getHeaderSearchOpts().PrebuiltModuleFiles.emplace("M", "/home/ykiko/C++/clice2/build/cache/xxx.pcm");
+    auto instance = createInstance(std::move(invocation));
+    auto action = std::make_unique<clang::SyntaxOnlyAction>();
+
+    if(!action->BeginSourceFile(*instance, instance->getFrontendOpts().Inputs[0])) {
+        llvm::errs() << "Failed to begin source file\n";
+        std::terminate();
+    }
+
+    if(auto error = action->Execute()) {
+        llvm::errs() << "Failed to execute action: " << error << "\n";
+        std::terminate();
+    }
+
+    instance->getASTContext().getTranslationUnitDecl()->dump();
+}
+
 }  // namespace