From c884c23225743eeeeca2f0dac1258f18a3a10413 Mon Sep 17 00:00:00 2001
From: Adrian Prantl <aprantl@apple.com>
Date: Wed, 17 Aug 2016 16:20:32 +0000
Subject: [PATCH] Debug info: Mark noreturn functions with DIFlagNoReturn.

This affects functions with the C++11 [[ noreturn ]] and C11 _Noreturn
specifiers.

Patch by Victor Leschuk!

https://reviews.llvm.org/D23168

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@278942 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/AST/Decl.cpp            | 10 +++++++---
 lib/CodeGen/CGDebugInfo.cpp |  3 +++
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/lib/AST/Decl.cpp b/lib/AST/Decl.cpp
index 98711822a5..cf34c7ab8d 100644
--- a/lib/AST/Decl.cpp
+++ b/lib/AST/Decl.cpp
@@ -2657,9 +2657,13 @@ bool FunctionDecl::isGlobal() const {
 }
 
 bool FunctionDecl::isNoReturn() const {
-  return hasAttr<NoReturnAttr>() || hasAttr<CXX11NoReturnAttr>() ||
-         hasAttr<C11NoReturnAttr>() ||
-         getType()->getAs<FunctionType>()->getNoReturnAttr();
+  bool HasNoReturnAttr = hasAttr<NoReturnAttr>() || hasAttr<CXX11NoReturnAttr>()
+                         || hasAttr<C11NoReturnAttr>();
+  const auto *FuncType = getType()->getAs<FunctionType>();
+  bool TypeHasNoReturnAttr = false;
+  if (FuncType)
+    TypeHasNoReturnAttr = FuncType->getNoReturnAttr();
+  return HasNoReturnAttr || TypeHasNoReturnAttr;
 }
 
 void
diff --git a/lib/CodeGen/CGDebugInfo.cpp b/lib/CodeGen/CGDebugInfo.cpp
index ee2e21bdd4..f56cd0a6bb 100644
--- a/lib/CodeGen/CGDebugInfo.cpp
+++ b/lib/CodeGen/CGDebugInfo.cpp
@@ -2646,6 +2646,9 @@ void CGDebugInfo::collectFunctionDeclProps(GlobalDecl GD, llvm::DIFile *Unit,
       llvm::DIScope *Mod = getParentModuleOrNull(RDecl);
       FDContext = getContextDescriptor(RDecl, Mod ? Mod : TheCU);
     }
+    // Check if it is a noreturn-marked function
+    if (FD->isNoReturn())
+      Flags |= llvm::DINode::FlagNoReturn;
     // Collect template parameters.
     TParamsArray = CollectFunctionTemplateParams(FD, Unit);
   }
-- 
2.40.0