[CodeGen] Consider MangleCtx when move lazy emission States

[junaire]

Summary

Also move MangleCtx when moving some lazy emission states in
CodeGenModule. Without this patch clang-repl hits an invalid address
access when passing -Xcc -O2 flag.

Signed-off-by: Jun Zhang <[e-mail]>

[v.g.vassilev]

Let's add more reviewers.

[rjmccall]

I think this seems reasonable. I suspect we'll need to do more plumbing here if we need to support snapshotting / resetting to a snapshot, but this probably isn't the only place, and the moves we're doing aren't set up for that either.

clang/lib/CodeGen/CGCXXABI.h

 namespace CodeGen {
 class CGCallee;
 class CodeGenFunction;
 class CodeGenModule;
 struct CatchTypeInfo;
 
 /// Implements C++ ABI-specific code generation functions.
 class CGCXXABI {
+  friend class CodeGenModule;
+
 protected:
   CodeGenModule &CGM;
   std::unique_ptr<MangleContext> MangleCtx;
 
   CGCXXABI(CodeGenModule &CGM)
     : CGM(CGM), MangleCtx(CGM.getContext().createMangleContext()) {}
 
 protected:

clang/lib/CodeGen/CodeGenModule.cpp

void CodeGenModule::moveLazyEmissionStates(CodeGenModule *NewBuilder) {
   NewBuilder->WeakRefReferences = std::move(WeakRefReferences);
 
   NewBuilder->TBAA = std::move(TBAA);
 
   assert(NewBuilder->EmittedDeferredDecls.empty() &&
          "Still have (unmerged) EmittedDeferredDecls deferred decls");
 
   NewBuilder->EmittedDeferredDecls = std::move(EmittedDeferredDecls);
+
+  NewBuilder->ABI->MangleCtx = std::move(ABI->MangleCtx);
 }

clang/test/Interpreter/execute.cpp

 // RUN: clang-repl "int x = 10;" "int y=7; err;" "int y = 10;"
 // RUN: clang-repl "int i = 10;" 'extern "C" int printf(const char*,...);' \
 // RUN:            'auto r1 = printf("i = %d\n", i);' | FileCheck --check-prefix=CHECK-DRIVER %s
 // REQUIRES: host-supports-jit
 // UNSUPPORTED: system-aix
 // CHECK-DRIVER: i = 10
 // RUN: cat %s | clang-repl | FileCheck %s
+// RUN: cat %s | clang-repl -Xcc -O2 | FileCheck %s
 extern "C" int printf(const char *, ...);
 int i = 42;
 auto r1 = printf("i = %d\n", i);
 // CHECK: i = 42
 
 struct S { float f = 1.0; S *m = nullptr;} s;
 
 auto r2 = printf("S[f=%f, m=0x%llx]\n", s.f, reinterpret_cast<unsigned long long>(s.m));
 // CHECK-NEXT: S[f=1.000000, m=0x0]
 
 inline int foo() { return 42; }
 int r3 = foo();
 
 %quit