From 1741d118bf6aea742c37d78500539616c1ffc8af Mon Sep 17 00:00:00 2001
From: Adrian Prantl <aprantl@apple.com>
Date: Tue, 25 Feb 2014 19:38:11 +0000
Subject: [PATCH] Debug info: Generate debug info for variadic functions.
 Paired commit with LLVM.

rdar://problem/13690847

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@202185 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/CodeGen/CGDebugInfo.cpp            | 16 ++++++++++++++++
 test/CodeGenCXX/debug-info-varargs.cpp | 24 ++++++++++++++++++++++++
 2 files changed, 40 insertions(+)
 create mode 100644 test/CodeGenCXX/debug-info-varargs.cpp

diff --git a/lib/CodeGen/CGDebugInfo.cpp b/lib/CodeGen/CGDebugInfo.cpp
index a72f9e6bf7..2de4dde127 100644
--- a/lib/CodeGen/CGDebugInfo.cpp
+++ b/lib/CodeGen/CGDebugInfo.cpp
@@ -765,6 +765,8 @@ llvm::DIType CGDebugInfo::CreateType(const FunctionType *Ty,
   else if (const FunctionProtoType *FPT = dyn_cast<FunctionProtoType>(Ty)) {
     for (unsigned i = 0, e = FPT->getNumParams(); i != e; ++i)
       EltTys.push_back(getOrCreateType(FPT->getParamType(i), Unit));
+    if (FPT->isVariadic())
+      EltTys.push_back(DBuilder.createUnspecifiedParameter());
   }
 
   llvm::DIArray EltTypeArray = DBuilder.getOrCreateArray(EltTys);
@@ -2437,6 +2439,20 @@ llvm::DICompositeType CGDebugInfo::getOrCreateFunctionType(const Decl *D,
     llvm::DIArray EltTypeArray = DBuilder.getOrCreateArray(Elts);
     return DBuilder.createSubroutineType(F, EltTypeArray);
   }
+
+  // Variadic function.
+  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D))
+    if (FD->isVariadic()) {
+      SmallVector<llvm::Value *, 16> EltTys;
+      EltTys.push_back(getOrCreateType(FD->getReturnType(), F));
+      if (const FunctionProtoType *FPT = dyn_cast<FunctionProtoType>(FnType))
+        for (unsigned i = 0, e = FPT->getNumParams(); i != e; ++i)
+          EltTys.push_back(getOrCreateType(FPT->getParamType(i), F));
+      EltTys.push_back(DBuilder.createUnspecifiedParameter());
+      llvm::DIArray EltTypeArray = DBuilder.getOrCreateArray(EltTys);
+      return DBuilder.createSubroutineType(F, EltTypeArray);
+    }
+
   return llvm::DICompositeType(getOrCreateType(FnType, F));
 }
 
diff --git a/test/CodeGenCXX/debug-info-varargs.cpp b/test/CodeGenCXX/debug-info-varargs.cpp
new file mode 100644
index 0000000000..de469642be
--- /dev/null
+++ b/test/CodeGenCXX/debug-info-varargs.cpp
@@ -0,0 +1,24 @@
+// RUN: %clang_cc1 -emit-llvm -g %s -o - | FileCheck %s
+
+struct A
+{
+  // CHECK-DAG: ", i32 [[@LINE+1]], metadata ![[ATY:[0-9]+]]{{.*}}[ DW_TAG_subprogram ]{{.*}}[a]
+  void a(int c, ...) {}
+  // CHECK-DAG: ![[ATY]] ={{.*}} metadata ![[AARGS:[0-9]+]], i32 0, null, null, null} ; [ DW_TAG_subroutine_type ]
+  // CHECK-DAG: ![[AARGS]] = {{.*}} metadata ![[UNSPEC:[0-9]+]]}
+  // CHECK-DAG: ![[UNSPEC]] = metadata !{i32 786456}
+};
+
+  // CHECK-DAG: ", i32 [[@LINE+1]], metadata ![[BTY:[0-9]+]]{{.*}}[ DW_TAG_subprogram ]{{.*}}[b]
+void b(int c, ...) {
+  // CHECK-DAG: ![[BTY]] ={{.*}} metadata ![[BARGS:[0-9]+]], i32 0, null, null, null} ; [ DW_TAG_subroutine_type ]
+  // CHECK-DAG: ![[BARGS]] = {{.*}} metadata ![[UNSPEC:[0-9]+]]}
+
+  A a;
+
+  // CHECK-DAG: metadata ![[PST:[0-9]+]], i32 0, i32 0} ; [ DW_TAG_auto_variable ] [fptr] [line [[@LINE+1]]]
+  void (*fptr)(int, ...) = b;
+  // CHECK-DAG: ![[PST]] ={{.*}} metadata ![[ST:[0-9]+]]} ; [ DW_TAG_pointer_type ]
+  // CHECK-DAG: ![[ST]] ={{.*}} metadata ![[ARGS:[0-9]+]], i32 0, null, null, null} ; [ DW_TAG_subroutine_type ]
+  // CHECK-DAG: ![[ARGS]] = {{.*}} metadata ![[UNSPEC]]}
+}
-- 
2.40.0