Avoid iteration invalidation issues around MaterializedTemporaryExpr

We risk iterator invalidation issues if we use a DenseMap to hold the
backing storage for an APValue.  Instead, BumpPtrAllocate them and
use APValue * as our DenseMap value.

Also, don't assume that MaterializedGlobalTemporaryMap won't regrow
between when we initially perform a lookup and later on when we actually
try to insert into it.

This fixes PR24289.

Differential Revision: http://reviews.llvm.org/D11629

llvm-svn: 244989

4 files changed, 94 insertions, 10 deletions

diff --git a/clang/include/clang/AST/ASTContext.h b/clang/include/clang/AST/ASTContext.h
index dc9bc29d8da..68bf211a0fb 100644
--- a/clang/include/clang/AST/ASTContext.h
+++ b/clang/include/clang/AST/ASTContext.h
@@ -176,8 +176,9 @@ class ASTContext : public RefCountedBase<ASTContext> {
     ClassScopeSpecializationPattern;
 
   /// \brief Mapping from materialized temporaries with static storage duration
-  /// that appear in constant initializers to their evaluated values.
-  llvm::DenseMap<const MaterializeTemporaryExpr*, APValue>
+  /// that appear in constant initializers to their evaluated values.  These are
+  /// allocated in a std::map because their address must be stable.
+  llvm::DenseMap<const MaterializeTemporaryExpr *, APValue *>
     MaterializedTemporaryValues;
 
   /// \brief Representation of a "canonical" template template parameter that
diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index bc94bd0bb57..d0c58ef994b 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -8553,12 +8553,14 @@ ASTContext::getMaterializedTemporaryValue(const MaterializeTemporaryExpr *E,
                                           bool MayCreate) {
   assert(E && E->getStorageDuration() == SD_Static &&
          "don't need to cache the computed value for this temporary");
-  if (MayCreate)
-    return &MaterializedTemporaryValues[E];
+  if (MayCreate) {
+    APValue *&MTVI = MaterializedTemporaryValues[E];
+    if (!MTVI)
+      MTVI = new (*this) APValue;
+    return MTVI;
+  }
 
-  llvm::DenseMap<const MaterializeTemporaryExpr *, APValue>::iterator I =
-      MaterializedTemporaryValues.find(E);
-  return I == MaterializedTemporaryValues.end() ? nullptr : &I->second;
+  return MaterializedTemporaryValues.lookup(E);
 }
 
 bool ASTContext::AtomicUsesUnsupportedLibcall(const AtomicExpr *E) const {
diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index 5ce25a29d48..76e6f3dcde4 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -3029,8 +3029,7 @@ llvm::Constant *CodeGenModule::GetAddrOfGlobalTemporary(
   if (Init == E->GetTemporaryExpr())
     MaterializedType = E->getType();
 
-  llvm::Constant *&Slot = MaterializedGlobalTemporaryMap[E];
-  if (Slot)
+  if (llvm::Constant *Slot = MaterializedGlobalTemporaryMap[E])
     return Slot;
 
   // FIXME: If an externally-visible declaration extends multiple temporaries,
@@ -3101,7 +3100,7 @@ llvm::Constant *CodeGenModule::GetAddrOfGlobalTemporary(
     GV->setComdat(TheModule.getOrInsertComdat(GV->getName()));
   if (VD->getTLSKind())
     setTLSMode(GV, *VD);
-  Slot = GV;
+  MaterializedGlobalTemporaryMap[E] = GV;
   return GV;
 }
 
diff --git a/clang/test/CodeGenCXX/PR24289.cpp b/clang/test/CodeGenCXX/PR24289.cpp
new file mode 100644
index 00000000000..364b5b23385
--- /dev/null
+++ b/clang/test/CodeGenCXX/PR24289.cpp
@@ -0,0 +1,82 @@
+// RUN: %clang_cc1 -emit-llvm %s -o - -triple=x86_64-pc-linux-gnu -std=c++11 | FileCheck %s
+
+namespace std {
+template <class T>
+struct initializer_list {
+  const T *Begin;
+  __SIZE_TYPE__ Size;
+
+  constexpr initializer_list(const T *B, __SIZE_TYPE__ S)
+      : Begin(B), Size(S) {}
+};
+}
+
+void f() {
+  static std::initializer_list<std::initializer_list<int>> a{
+      {0}, {0}, {0}, {0}, {0}, {0}, {0}, {0}, {0}, {0}, {0}, {0}, {0}, {0}};
+  static std::initializer_list<std::initializer_list<int>> b{
+      {0}, {0}, {0}, {0}};
+  static std::initializer_list<std::initializer_list<int>> c{
+      {0}, {0}, {0}, {0}, {0}, {0}, {0}, {0}, {0}};
+  static std::initializer_list<std::initializer_list<int>> d{
+      {0}, {0}, {0}, {0}, {0}};
+  static std::initializer_list<std::initializer_list<int>> e{
+      {0}, {0}, {0}, {0}, {0}, {0}, {0}, {0}, {0}, {0}, {0}};
+}
+
+// CHECK-DAG: @_ZZ1fvE1a = internal global %{{.*}} { %{{.*}}* getelementptr inbounds ([14 x %{{.*}}], [14 x %{{.*}}]
+// CHECK-DAG: * @_ZGRZ1fvE1a_, i32 0, i32 0), i64 14 }
+// CHECK-DAG: @_ZGRZ1fvE1a0_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1a1_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1a2_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1a3_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1a4_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1a5_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1a6_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1a7_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1a8_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1a9_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1aA_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1aB_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1aC_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1aD_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1a_ = internal constant [14 x %{{.*}}] [%{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1a0_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1a1_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1a2_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1a3_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1a4_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1a5_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1a6_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1a7_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1a8_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1a9_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1aA_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1aB_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1aC_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1aD_, i32 0, i32 0), i64 1 }]
+// CHECK-DAG: @_ZZ1fvE1b = internal global %{{.*}} { %{{.*}}* getelementptr inbounds ([4 x %{{.*}}], [4 x %{{.*}}]*
+// CHECK-DAG: @_ZGRZ1fvE1b_, i32 0, i32 0), i64 4 }
+// CHECK-DAG: @_ZGRZ1fvE1b0_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1b1_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1b2_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1b3_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1b_ = internal constant [4 x %{{.*}}] [%{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1b0_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1b1_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1b2_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1b3_, i32 0, i32 0), i64 1 }]
+// CHECK-DAG: @_ZZ1fvE1c = internal global %{{.*}} { %{{.*}}* getelementptr inbounds ([9 x %{{.*}}], [9 x %{{.*}}]*
+// CHECK-DAG: @_ZGRZ1fvE1c_, i32 0, i32 0), i64 9 }
+// CHECK-DAG: @_ZGRZ1fvE1c0_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1c1_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1c2_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1c3_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1c4_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1c5_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1c6_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1c7_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1c8_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1c_ = internal constant [9 x %{{.*}}] [%{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1c0_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1c1_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1c2_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1c3_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1c4_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1c5_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1c6_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1c7_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1c8_, i32 0, i32 0), i64 1 }]
+// CHECK-DAG: @_ZZ1fvE1d = internal global %{{.*}} { %{{.*}}* getelementptr inbounds ([5 x %{{.*}}], [5 x %{{.*}}]* @_ZGRZ1fvE1d_, i32 0, i32 0), i64 5 }
+// CHECK-DAG: @_ZGRZ1fvE1d0_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1d1_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1d2_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1d3_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1d4_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1d_ = internal constant [5 x %{{.*}}] [%{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1d0_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1d1_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1d2_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1d3_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1d4_, i32 0, i32 0), i64 1 }]
+// CHECK-DAG: @_ZZ1fvE1e = internal global %{{.*}} { %{{.*}}* getelementptr inbounds ([11 x %{{.*}}], [11 x %{{.*}}]* @_ZGRZ1fvE1e_, i32 0, i32 0), i64 11 }
+// CHECK-DAG: @_ZGRZ1fvE1e0_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1e1_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1e2_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1e3_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1e4_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1e5_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1e6_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1e7_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1e8_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1e9_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1eA_ = internal constant [1 x i32] zeroinitializer
+// CHECK-DAG: @_ZGRZ1fvE1e_ = internal constant [11 x %{{.*}}] [%{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1e0_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1e1_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1e2_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1e3_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1e4_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1e5_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1e6_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1e7_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1e8_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1e9_, i32 0, i32 0), i64 1 }, %{{.*}} { i32* getelementptr inbounds ([1 x i32], [1 x i32]* @_ZGRZ1fvE1eA_, i32 0, i32 0), i64 1 }]