[clang] Clang repl implicit executor create (PR #84758)

[Stefan Gränitz via cfe-commits]

https://github.com/weliveindetail created https://github.com/llvm/llvm-project/pull/84758

Until now the IncrExecutor is created lazily on the first execution request. In order to process the PTUs that come from initialization, we have to do it upfront implicitly.

>From 2f7b523472543a92a97701880f8cd3c928061f53 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Stefan=20Gr=C3=A4nitz?= <stefan.graenitz at gmail.com>
Date: Sun, 10 Mar 2024 18:17:48 +0100
Subject: [PATCH 1/2] [clang-repl] Set up executor implicitly to account for
 init PTUs

---
 clang/lib/Interpreter/Interpreter.cpp | 30 +++++++++++++++++++++++----
 clang/test/Interpreter/execute.cpp    |  4 ++--
 2 files changed, 28 insertions(+), 6 deletions(-)

diff --git a/clang/lib/Interpreter/Interpreter.cpp b/clang/lib/Interpreter/Interpreter.cpp
index e293fefb524963..5e1161ca472b36 100644
--- a/clang/lib/Interpreter/Interpreter.cpp
+++ b/clang/lib/Interpreter/Interpreter.cpp
@@ -229,12 +229,30 @@ IncrementalCompilerBuilder::CreateCudaHost() {
 }
 
 Interpreter::Interpreter(std::unique_ptr<CompilerInstance> CI,
-                         llvm::Error &Err) {
-  llvm::ErrorAsOutParameter EAO(&Err);
+                         llvm::Error &ErrOut) {
+  llvm::ErrorAsOutParameter EAO(&ErrOut);
   auto LLVMCtx = std::make_unique<llvm::LLVMContext>();
   TSCtx = std::make_unique<llvm::orc::ThreadSafeContext>(std::move(LLVMCtx));
-  IncrParser = std::make_unique<IncrementalParser>(*this, std::move(CI),
-                                                   *TSCtx->getContext(), Err);
+  IncrParser = std::make_unique<IncrementalParser>(
+      *this, std::move(CI), *TSCtx->getContext(), ErrOut);
+  if (ErrOut)
+    return;
+
+  // Not all frontends support code-generation, e.g. ast-dump actions don't
+  if (IncrParser->getCodeGen()) {
+    if (llvm::Error Err = CreateExecutor()) {
+      ErrOut = joinErrors(std::move(ErrOut), std::move(Err));
+      return;
+    }
+
+    // Process the PTUs that came from initialization. For example -include will
+    // give us a header that's processed at initialization of the preprocessor.
+    for (PartialTranslationUnit &PTU : IncrParser->getPTUs())
+      if (llvm::Error Err = Execute(PTU)) {
+        ErrOut = joinErrors(std::move(ErrOut), std::move(Err));
+        return;
+      }
+  }
 }
 
 Interpreter::~Interpreter() {
@@ -375,6 +393,10 @@ Interpreter::Parse(llvm::StringRef Code) {
 llvm::Error Interpreter::CreateExecutor() {
   const clang::TargetInfo &TI =
       getCompilerInstance()->getASTContext().getTargetInfo();
+  if (!IncrParser->getCodeGen())
+    return llvm::make_error<llvm::StringError>("Operation failed. "
+                                               "No code generator available",
+                                               std::error_code());
   llvm::Error Err = llvm::Error::success();
   auto Executor = std::make_unique<IncrementalExecutor>(*TSCtx, Err, TI);
   if (!Err)
diff --git a/clang/test/Interpreter/execute.cpp b/clang/test/Interpreter/execute.cpp
index 6e73ed3927e815..534a54ed94fba2 100644
--- a/clang/test/Interpreter/execute.cpp
+++ b/clang/test/Interpreter/execute.cpp
@@ -7,6 +7,8 @@
 
 // RUN: cat %s | clang-repl | FileCheck %s
 // RUN: cat %s | clang-repl -Xcc -O2 | FileCheck %s
+// RUN: clang-repl -Xcc -include -Xcc %s | FileCheck %s
+// RUN: clang-repl -Xcc -fsyntax-only -Xcc -include -Xcc %s
 extern "C" int printf(const char *, ...);
 int i = 42;
 auto r1 = printf("i = %d\n", i);
@@ -19,5 +21,3 @@ auto r2 = printf("S[f=%f, m=0x%llx]\n", s.f, reinterpret_cast<unsigned long long
 
 inline int foo() { return 42; }
 int r3 = foo();
-
-%quit

>From e68cb564114721016a879d6afd84868ad2169bd0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Stefan=20Gr=C3=A4nitz?= <stefan.graenitz at gmail.com>
Date: Mon, 11 Mar 2024 14:10:58 +0100
Subject: [PATCH 2/2] [tmp] Add crash note

---
 clang/test/Interpreter/inline-virtual.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/clang/test/Interpreter/inline-virtual.cpp b/clang/test/Interpreter/inline-virtual.cpp
index 79ab8ed337ffea..d862b3354f61fe 100644
--- a/clang/test/Interpreter/inline-virtual.cpp
+++ b/clang/test/Interpreter/inline-virtual.cpp
@@ -14,7 +14,7 @@ struct A { int a; A(int a) : a(a) {} virtual ~A(); };
 // PartialTranslationUnit.
 inline A::~A() { printf("~A(%d)\n", a); }
 
-// Create one instance with new and delete it.
+// Create one instance with new and delete it. We crash here now:
 A *a1 = new A(1);
 delete a1;
 // CHECK: ~A(1)