[ubsan] Reduce alignment checking of C++ object pointers

This patch teaches ubsan to insert an alignment check for the 'this'
pointer at the start of each method/lambda. This allows clang to emit
significantly fewer alignment checks overall, because if 'this' is
aligned, so are its fields.

This is essentially the same thing r295515 does, but for the alignment
check instead of the null check. One difference is that we keep the
alignment checks on member expressions where the base is a DeclRefExpr.
There's an opportunity to diagnose unaligned accesses in this situation
(as pointed out by Eli, see PR32630).

Testing: check-clang, check-ubsan, and a stage2 ubsan build.

Along with the patch from D30285, this roughly halves the amount of
alignment checks we emit when compiling X86FastISel.cpp. Here are the
numbers from patched/unpatched clangs based on r298160.

  ------------------------------------------
  | Setup          | # of alignment checks |
  ------------------------------------------
  | unpatched, -O0 |                 24326 |
  | patched, -O0   |                 12717 | (-47.7%)
  ------------------------------------------

Differential Revision: https://reviews.llvm.org/D30283

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@300370 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/CGExpr.cpp b/lib/CodeGen/CGExpr.cpp
index a0dd20b5f6a2a3fd9a186dceaf3dedf046d2ec9f..428c8ffd2a139699c2a67d7eb6322b4b04c5971f 100644 (file)
--- a/lib/CodeGen/CGExpr.cpp
+++ b/lib/CodeGen/CGExpr.cpp
@@ -954,10 +954,7 @@ LValue CodeGenFunction::EmitUnsupportedLValue(const Expr *E,
                         E->getType());
 }
 
-bool CodeGenFunction::IsDeclRefOrWrappedCXXThis(const Expr *Obj) {
-  if (isa<DeclRefExpr>(Obj))
-    return true;
-
+bool CodeGenFunction::IsWrappedCXXThis(const Expr *Obj) {
   const Expr *Base = Obj;
   while (!isa<CXXThisExpr>(Base)) {
     // The result of a dynamic_cast can be null.
@@ -988,9 +985,13 @@ LValue CodeGenFunction::EmitCheckedLValue(const Expr *E, TypeCheckKind TCK) {
     LV = EmitLValue(E);
   if (!isa<DeclRefExpr>(E) && !LV.isBitField() && LV.isSimple()) {
     SanitizerSet SkippedChecks;
-    if (const auto *ME = dyn_cast<MemberExpr>(E))
-      if (IsDeclRefOrWrappedCXXThis(ME->getBase()))
+    if (const auto *ME = dyn_cast<MemberExpr>(E)) {
+      bool IsBaseCXXThis = IsWrappedCXXThis(ME->getBase());
+      if (IsBaseCXXThis)
+        SkippedChecks.set(SanitizerKind::Alignment, true);
+      if (IsBaseCXXThis || isa<DeclRefExpr>(ME->getBase()))
         SkippedChecks.set(SanitizerKind::Null, true);
+    }
     EmitTypeCheck(TCK, E->getExprLoc(), LV.getPointer(),
                   E->getType(), LV.getAlignment(), SkippedChecks);
   }
@@ -3429,7 +3430,10 @@ LValue CodeGenFunction::EmitMemberExpr(const MemberExpr *E) {
     Address Addr = EmitPointerWithAlignment(BaseExpr, &AlignSource);
     QualType PtrTy = BaseExpr->getType()->getPointeeType();
     SanitizerSet SkippedChecks;
-    if (IsDeclRefOrWrappedCXXThis(BaseExpr))
+    bool IsBaseCXXThis = IsWrappedCXXThis(BaseExpr);
+    if (IsBaseCXXThis)
+      SkippedChecks.set(SanitizerKind::Alignment, true);
+    if (IsBaseCXXThis || isa<DeclRefExpr>(BaseExpr))
       SkippedChecks.set(SanitizerKind::Null, true);
     EmitTypeCheck(TCK_MemberAccess, E->getExprLoc(), Addr.getPointer(), PtrTy,
                   /*Alignment=*/CharUnits::Zero(), SkippedChecks);

diff --git a/lib/CodeGen/CGExprCXX.cpp b/lib/CodeGen/CGExprCXX.cpp
index c4db670ec4ef70d78dd78540c2f962e4e9dc1b9f..d02f074dd605fdab530be3f2313c386f120421f6 100644 (file)
--- a/lib/CodeGen/CGExprCXX.cpp
+++ b/lib/CodeGen/CGExprCXX.cpp
@@ -301,9 +301,14 @@ RValue CodeGenFunction::EmitCXXMemberOrOperatorMemberCallExpr(
     CallLoc = CE->getExprLoc();
 
   SanitizerSet SkippedChecks;
-  if (const auto *CMCE = dyn_cast<CXXMemberCallExpr>(CE))
-    if (IsDeclRefOrWrappedCXXThis(CMCE->getImplicitObjectArgument()))
+  if (const auto *CMCE = dyn_cast<CXXMemberCallExpr>(CE)) {
+    auto *IOA = CMCE->getImplicitObjectArgument();
+    bool IsImplicitObjectCXXThis = IsWrappedCXXThis(IOA);
+    if (IsImplicitObjectCXXThis)
+      SkippedChecks.set(SanitizerKind::Alignment, true);
+    if (IsImplicitObjectCXXThis || isa<DeclRefExpr>(IOA))
       SkippedChecks.set(SanitizerKind::Null, true);
+  }
   EmitTypeCheck(
       isa<CXXConstructorDecl>(CalleeDecl) ? CodeGenFunction::TCK_ConstructorCall
                                           : CodeGenFunction::TCK_MemberCall,

diff --git a/lib/CodeGen/CodeGenFunction.cpp b/lib/CodeGen/CodeGenFunction.cpp
index 346679b08f656e63a76091915f749bdb93855595..6e6eb7d7f13c64440aa1c180f2b7fea3aab0ad05 100644 (file)
--- a/lib/CodeGen/CodeGenFunction.cpp
+++ b/lib/CodeGen/CodeGenFunction.cpp
@@ -963,13 +963,14 @@ void CodeGenFunction::StartFunction(GlobalDecl GD,
       CXXThisValue = CXXABIThisValue;
     }
 
-    // Null-check the 'this' pointer once per function, if it's available.
+    // Check the 'this' pointer once per function, if it's available.
     if (CXXThisValue) {
       SanitizerSet SkippedChecks;
-      SkippedChecks.set(SanitizerKind::Alignment, true);
       SkippedChecks.set(SanitizerKind::ObjectSize, true);
-      EmitTypeCheck(TCK_Load, Loc, CXXThisValue, MD->getThisType(getContext()),
-                    /*Alignment=*/CharUnits::Zero(), SkippedChecks);
+      QualType ThisTy = MD->getThisType(getContext());
+      EmitTypeCheck(TCK_Load, Loc, CXXThisValue, ThisTy,
+                    getContext().getTypeAlignInChars(ThisTy->getPointeeType()),
+                    SkippedChecks);
     }
   }
 

diff --git a/lib/CodeGen/CodeGenFunction.h b/lib/CodeGen/CodeGenFunction.h
index 3321bc86c000e033376db9ba88ec7b999e6b3bc6..fa72019eb08b2a7b4a271a2da438ae45875796ff 100644 (file)
--- a/lib/CodeGen/CodeGenFunction.h
+++ b/lib/CodeGen/CodeGenFunction.h
@@ -2077,9 +2077,8 @@ public:
   llvm::BlockAddress *GetAddrOfLabel(const LabelDecl *L);
   llvm::BasicBlock *GetIndirectGotoBlock();
 
-  /// Check if \p E is a reference, or a C++ "this" pointer wrapped in value-
-  /// preserving casts.
-  static bool IsDeclRefOrWrappedCXXThis(const Expr *E);
+  /// Check if \p E is a C++ "this" pointer wrapped in value-preserving casts.
+  static bool IsWrappedCXXThis(const Expr *E);
 
   /// EmitNullInitialization - Generate code to set a value of the given type to
   /// null, If the type contains data member pointers, they will be initialized

diff --git a/test/CodeGenCXX/ubsan-global-alignment.cpp b/test/CodeGenCXX/ubsan-global-alignment.cpp
new file mode 100644 (file)
index 0000000..67fcfd4
--- /dev/null
+++ b/test/CodeGenCXX/ubsan-global-alignment.cpp
@@ -0,0 +1,29 @@
+// RUN: %clang_cc1 -std=c++11 -triple x86_64-apple-darwin10 -emit-llvm -o - %s -fsanitize=alignment | FileCheck %s
+
+struct S {
+  int I;
+};
+
+extern S g_S;
+extern S array_S[];
+
+// CHECK-LABEL: define i32 @_Z18load_extern_global
+int load_extern_global() {
+  // FIXME: The IR builder constant-folds the alignment check away to 'true'
+  // here, so we never call the diagnostic. This is PR32630.
+  // CHECK-NOT: ptrtoint i32* {{.*}} to i32, !nosanitize
+  // CHECK: [[I:%.*]] = load i32, i32* getelementptr inbounds (%struct.S, %struct.S* @g_S, i32 0, i32 0), align 4
+  // CHECK-NEXT: ret i32 [[I]]
+  return g_S.I;
+}
+
+// CHECK-LABEL: define i32 @_Z22load_from_extern_array
+int load_from_extern_array(int I) {
+  // CHECK: [[I:%.*]] = getelementptr inbounds %struct.S, %struct.S* {{.*}}, i32 0, i32 0
+  // CHECK-NEXT: [[PTRTOINT:%.*]] = ptrtoint i32* [[I]] to i64, !nosanitize
+  // CHECK-NEXT: [[AND:%.*]] = and i64 [[PTRTOINT]], 3, !nosanitize
+  // CHECK-NEXT: [[ICMP:%.*]] = icmp eq i64 [[AND]], 0, !nosanitize
+  // CHECK-NEXT: br i1 [[ICMP]]
+  // CHECK: call void @__ubsan_handle_type_mismatch
+  return array_S[I].I;
+}

diff --git a/test/CodeGenCXX/ubsan-suppress-checks.cpp b/test/CodeGenCXX/ubsan-suppress-checks.cpp
new file mode 100644 (file)
index 0000000..6ad417e
--- /dev/null
+++ b/test/CodeGenCXX/ubsan-suppress-checks.cpp
@@ -0,0 +1,221 @@
+// RUN: %clang_cc1 -std=c++11 -triple x86_64-apple-darwin10 -emit-llvm -o - %s -fsanitize=alignment | FileCheck %s --check-prefixes=CHECK,ALIGN
+// RUN: %clang_cc1 -std=c++11 -triple x86_64-apple-darwin10 -emit-llvm -o - %s -fsanitize=null | FileCheck %s --check-prefixes=CHECK,NULL
+// RUN: %clang_cc1 -std=c++11 -triple x86_64-apple-darwin10 -emit-llvm -o - %s -fsanitize=alignment,null -DCHECK_LAMBDA | FileCheck %s --check-prefixes=LAMBDA
+
+struct A {
+  int foo;
+
+  // CHECK-LABEL: define linkonce_odr void @_ZN1A10do_nothingEv
+  void do_nothing() {
+    // ALIGN: %[[THISINT1:[0-9]+]] = ptrtoint %struct.A* %{{.*}} to i64, !nosanitize
+    // ALIGN: and i64 %[[THISINT1]], 3, !nosanitize
+    // NULL: icmp ne %struct.A* %[[THIS1:[a-z0-9]+]], null, !nosanitize
+    // NULL: ptrtoint %struct.A* %[[THIS1]] to i64, !nosanitize
+    // CHECK: call void @__ubsan_handle_type_mismatch
+    // CHECK-NOT: call void @__ubsan_handle_type_mismatch
+    // CHECK: ret void
+  }
+
+#ifdef CHECK_LAMBDA
+  // LAMBDA-LABEL: define linkonce_odr void @_ZN1A22do_nothing_with_lambdaEv
+  void do_nothing_with_lambda() {
+    // LAMBDA: icmp ne %struct.A* %[[THIS2:[a-z0-9]+]], null, !nosanitize
+    // LAMBDA: %[[THISINT2:[0-9]+]] = ptrtoint %struct.A* %[[THIS2]] to i64, !nosanitize
+    // LAMBDA: and i64 %[[THISINT2]], 3, !nosanitize
+    // LAMBDA: call void @__ubsan_handle_type_mismatch
+
+    auto f = [&] {
+      foo = 0;
+    };
+    f();
+
+    // LAMBDA: icmp ne %class.anon* %[[FUNCVAR:.*]], null, !nosanitize
+    // LAMBDA: %[[LAMBDAINT:[0-9]+]] = ptrtoint %class.anon* %[[FUNCVAR]] to i64, !nosanitize
+    // LAMBDA: and i64 %[[LAMBDAINT]], 7, !nosanitize
+    // LAMBDA: call void @__ubsan_handle_type_mismatch
+
+    // LAMBDA-NOT: call void @__ubsan_handle_type_mismatch
+    // LAMBDA: ret void
+  }
+
+// Check the IR for the lambda:
+//
+// LAMBDA-LABEL: define linkonce_odr void @_ZZN1A22do_nothing_with_lambdaEvENKUlvE_clEv
+// LAMBDA: call void @__ubsan_handle_type_mismatch
+// LAMBDA-NOT: call void @__ubsan_handle_type_mismatch
+// LAMBDA: ret void
+#endif
+
+  // CHECK-LABEL: define linkonce_odr i32 @_ZN1A11load_memberEv
+  int load_member() {
+    // ALIGN: %[[THISINT3:[0-9]+]] = ptrtoint %struct.A* %{{.*}} to i64, !nosanitize
+    // ALIGN: and i64 %[[THISINT3]], 3, !nosanitize
+    // NULL: icmp ne %struct.A* %[[THIS3:[a-z0-9]+]], null, !nosanitize
+    // NULL: ptrtoint %struct.A* %[[THIS3]] to i64, !nosanitize
+    // CHECK: call void @__ubsan_handle_type_mismatch
+    // CHECK-NOT: call void @__ubsan_handle_type_mismatch
+    return foo;
+    // CHECK: ret i32
+  }
+
+  // CHECK-LABEL: define linkonce_odr i32 @_ZN1A11call_methodEv
+  int call_method() {
+    // ALIGN: %[[THISINT4:[0-9]+]] = ptrtoint %struct.A* %{{.*}} to i64, !nosanitize
+    // ALIGN: and i64 %[[THISINT4]], 3, !nosanitize
+    // NULL: icmp ne %struct.A* %[[THIS4:[a-z0-9]+]], null, !nosanitize
+    // NULL: ptrtoint %struct.A* %[[THIS4]] to i64, !nosanitize
+    // CHECK: call void @__ubsan_handle_type_mismatch
+    // CHECK-NOT: call void @__ubsan_handle_type_mismatch
+    return load_member();
+    // CHECK: ret i32
+  }
+
+  // CHECK-LABEL: define linkonce_odr void @_ZN1A15assign_member_1Ev
+  void assign_member_1() {
+    // ALIGN: %[[THISINT5:[0-9]+]] = ptrtoint %struct.A* %{{.*}} to i64, !nosanitize
+    // ALIGN: and i64 %[[THISINT5]], 3, !nosanitize
+    // NULL: icmp ne %struct.A* %[[THIS5:[a-z0-9]+]], null, !nosanitize
+    // NULL: ptrtoint %struct.A* %[[THIS5]] to i64, !nosanitize
+    // CHECK: call void @__ubsan_handle_type_mismatch
+    // CHECK-NOT: call void @__ubsan_handle_type_mismatch
+    foo = 0;
+    // CHECK: ret void
+  }
+
+  // CHECK-LABEL: define linkonce_odr void @_ZN1A15assign_member_2Ev
+  void assign_member_2() {
+    // ALIGN: %[[THISINT6:[0-9]+]] = ptrtoint %struct.A* %{{.*}} to i64, !nosanitize
+    // ALIGN: and i64 %[[THISINT6]], 3, !nosanitize
+    // NULL: icmp ne %struct.A* %[[THIS6:[a-z0-9]+]], null, !nosanitize
+    // NULL: ptrtoint %struct.A* %[[THIS6]] to i64, !nosanitize
+    // CHECK: call void @__ubsan_handle_type_mismatch
+    // CHECK-NOT: call void @__ubsan_handle_type_mismatch
+    (__extension__ (this))->foo = 0;
+    // CHECK: ret void
+  }
+
+  // CHECK-LABEL: define linkonce_odr void @_ZNK1A15assign_member_3Ev
+  void assign_member_3() const {
+    // ALIGN: %[[THISINT7:[0-9]+]] = ptrtoint %struct.A* %{{.*}} to i64, !nosanitize
+    // ALIGN: and i64 %[[THISINT7]], 3, !nosanitize
+    // NULL: icmp ne %struct.A* %[[THIS7:[a-z0-9]+]], null, !nosanitize
+    // NULL: ptrtoint %struct.A* %[[THIS7]] to i64, !nosanitize
+    // CHECK: call void @__ubsan_handle_type_mismatch
+    // CHECK-NOT: call void @__ubsan_handle_type_mismatch
+    const_cast<A *>(this)->foo = 0;
+    // CHECK: ret void
+  }
+
+  // CHECK-LABEL: define linkonce_odr i32 @_ZN1A22call_through_referenceERS_
+  static int call_through_reference(A &a) {
+    // ALIGN: %[[OBJINT:[0-9]+]] = ptrtoint %struct.A* %{{.*}} to i64, !nosanitize
+    // ALIGN: and i64 %[[OBJINT]], 3, !nosanitize
+    // ALIGN: call void @__ubsan_handle_type_mismatch
+    // NULL-NOT: call void @__ubsan_handle_type_mismatch
+    return a.load_member();
+    // CHECK: ret i32
+  }
+
+  // CHECK-LABEL: define linkonce_odr i32 @_ZN1A20call_through_pointerEPS_
+  static int call_through_pointer(A *a) {
+    // CHECK: call void @__ubsan_handle_type_mismatch
+    return a->load_member();
+    // CHECK: ret i32
+  }
+};
+
+struct B {
+  operator A*() const { return nullptr; }
+
+  // CHECK-LABEL: define linkonce_odr i32 @_ZN1B11load_memberEv
+  static int load_member() {
+    // Check &b before converting it to an A*.
+    // CHECK: call void @__ubsan_handle_type_mismatch
+    //
+    // Check the result of the conversion before using it.
+    // CHECK: call void @__ubsan_handle_type_mismatch
+    //
+    // CHECK-NOT: call void @__ubsan_handle_type_mismatch
+    B b;
+    return static_cast<A *>(b)->load_member();
+    // CHECK: ret i32
+  }
+};
+
+struct Base {
+  int foo;
+
+  virtual int load_member_1() = 0;
+};
+
+struct Derived : public Base {
+  int bar;
+
+  // CHECK-LABEL: define linkonce_odr i32 @_ZN7Derived13load_member_2Ev
+  int load_member_2() {
+    // ALIGN: %[[THISINT8:[0-9]+]] = ptrtoint %struct.Derived* %{{.*}} to i64, !nosanitize
+    // ALIGN: and i64 %[[THISINT8]], 7, !nosanitize
+    // ALIGN: call void @__ubsan_handle_type_mismatch
+    // NULL: icmp ne %struct.Derived* %[[THIS8:[a-z0-9]+]], null, !nosanitize
+    // NULL: ptrtoint %struct.Derived* %[[THIS8]] to i64, !nosanitize
+    // CHECK: call void @__ubsan_handle_type_mismatch
+    //
+    // Check the result of the cast before using it.
+    // CHECK: call void @__ubsan_handle_type_mismatch
+    //
+    // CHECK-NOT: call void @__ubsan_handle_type_mismatch
+    return dynamic_cast<Base *>(this)->load_member_1();
+    // CHECK: ret i32
+  }
+
+  // CHECK-LABEL: define linkonce_odr i32 @_ZN7Derived13load_member_3Ev
+  int load_member_3() {
+    // ALIGN: %[[THISINT9:[0-9]+]] = ptrtoint %struct.Derived* %{{.*}} to i64, !nosanitize
+    // ALIGN: and i64 %[[THISINT9]], 7, !nosanitize
+    // ALIGN: call void @__ubsan_handle_type_mismatch
+    // ALIGN: call void @__ubsan_handle_type_mismatch
+    // NULL: icmp ne %struct.Derived* %[[THIS9:[a-z0-9]+]], null, !nosanitize
+    // NULL: ptrtoint %struct.Derived* %[[THIS9]] to i64, !nosanitize
+    // CHECK: call void @__ubsan_handle_type_mismatch
+    // CHECK-NOT: call void @__ubsan_handle_type_mismatch
+    return reinterpret_cast<Derived *>(static_cast<Base *>(this))->foo;
+    // CHECK: ret i32
+  }
+
+  // CHECK-LABEL: define linkonce_odr i32 @_ZN7Derived13load_member_1Ev
+  int load_member_1() override {
+    // ALIGN: %[[THISINT10:[0-9]+]] = ptrtoint %struct.Derived* %{{.*}} to i64, !nosanitize
+    // ALIGN: and i64 %[[THISINT10]], 7, !nosanitize
+    // ALIGN: call void @__ubsan_handle_type_mismatch
+    // NULL: icmp ne %struct.Derived* %[[THIS10:[a-z0-9]+]], null, !nosanitize
+    // NULL: ptrtoint %struct.Derived* %[[THIS10]] to i64, !nosanitize
+    // CHECK: call void @__ubsan_handle_type_mismatch
+    // CHECK-NOT: call void @__ubsan_handle_type_mismatch
+    return foo + bar;
+    // CHECK: ret i32
+  }
+};
+
+void force_irgen() {
+  A *a;
+  a->do_nothing();
+#ifdef CHECK_LAMBDA
+  a->do_nothing_with_lambda();
+#endif
+  a->load_member();
+  a->call_method();
+  a->assign_member_1();
+  a->assign_member_2();
+  a->assign_member_3();
+  A::call_through_reference(*a);
+  A::call_through_pointer(a);
+
+  B::load_member();
+
+  Base *b = new Derived;
+  b->load_member_1();
+
+  Derived *d;
+  d->load_member_2();
+  d->load_member_3();
+}

diff --git a/test/CodeGenCXX/ubsan-suppress-null-checks.cpp b/test/CodeGenCXX/ubsan-suppress-null-checks.cpp
deleted file mode 100644 (file)
index 967c081..0000000
--- a/test/CodeGenCXX/ubsan-suppress-null-checks.cpp
+++ /dev/null
@@ -1,188 +0,0 @@
-// RUN: %clang_cc1 -std=c++11 -triple x86_64-apple-darwin10 -emit-llvm -o - %s -fsanitize=null | FileCheck %s
-// RUN: %clang_cc1 -std=c++11 -triple x86_64-apple-darwin10 -emit-llvm -o - %s -fsanitize=null -DCHECK_LAMBDA | FileCheck %s --check-prefix=LAMBDA
-
-struct A {
-  int foo;
-
-  // CHECK-LABEL: define linkonce_odr void @_ZN1A10do_nothingEv
-  void do_nothing() {
-    // CHECK: icmp ne %struct.A* %[[THIS1:[a-z0-9]+]], null, !nosanitize
-    // CHECK: ptrtoint %struct.A* %[[THIS1]] to i64, !nosanitize
-    // CHECK-NEXT: call void @__ubsan_handle_type_mismatch
-    // CHECK-NOT: call void @__ubsan_handle_type_mismatch
-    // CHECK: ret void
-  }
-
-#ifdef CHECK_LAMBDA
-  // LAMBDA-LABEL: define linkonce_odr void @_ZN1A22do_nothing_with_lambdaEv
-  void do_nothing_with_lambda() {
-    // LAMBDA: icmp ne %struct.A* %[[THIS2:[a-z0-9]+]], null, !nosanitize
-    // LAMBDA: ptrtoint %struct.A* %[[THIS2]] to i64, !nosanitize
-    // LAMBDA-NEXT: call void @__ubsan_handle_type_mismatch
-
-    auto f = [&] {
-      foo = 0;
-    };
-    f();
-
-    // LAMBDA: ret void
-  }
-
-// Check the IR for the lambda:
-//
-// LAMBDA-LABEL: define linkonce_odr void @_ZZN1A22do_nothing_with_lambdaEvENKUlvE_clEv
-// LAMBDA: call void @__ubsan_handle_type_mismatch
-// LAMBDA-NOT: call void @__ubsan_handle_type_mismatch
-// LAMBDA: ret void
-#endif
-
-  // CHECK-LABEL: define linkonce_odr i32 @_ZN1A11load_memberEv
-  int load_member() {
-    // CHECK: icmp ne %struct.A* %[[THIS3:[a-z0-9]+]], null, !nosanitize
-    // CHECK: ptrtoint %struct.A* %[[THIS3]] to i64, !nosanitize
-    // CHECK-NEXT: call void @__ubsan_handle_type_mismatch
-    // CHECK-NOT: call void @__ubsan_handle_type_mismatch
-    return foo;
-    // CHECK: ret i32
-  }
-
-  // CHECK-LABEL: define linkonce_odr i32 @_ZN1A11call_methodEv
-  int call_method() {
-    // CHECK: icmp ne %struct.A* %[[THIS4:[a-z0-9]+]], null, !nosanitize
-    // CHECK: ptrtoint %struct.A* %[[THIS4]] to i64, !nosanitize
-    // CHECK-NEXT: call void @__ubsan_handle_type_mismatch
-    // CHECK-NOT: call void @__ubsan_handle_type_mismatch
-    return load_member();
-    // CHECK: ret i32
-  }
-
-  // CHECK-LABEL: define linkonce_odr void @_ZN1A15assign_member_1Ev
-  void assign_member_1() {
-    // CHECK: icmp ne %struct.A* %[[THIS5:[a-z0-9]+]], null, !nosanitize
-    // CHECK: ptrtoint %struct.A* %[[THIS5]] to i64, !nosanitize
-    // CHECK-NEXT: call void @__ubsan_handle_type_mismatch
-    // CHECK-NOT: call void @__ubsan_handle_type_mismatch
-    foo = 0;
-    // CHECK: ret void
-  }
-
-  // CHECK-LABEL: define linkonce_odr void @_ZN1A15assign_member_2Ev
-  void assign_member_2() {
-    // CHECK: icmp ne %struct.A* %[[THIS6:[a-z0-9]+]], null, !nosanitize
-    // CHECK: ptrtoint %struct.A* %[[THIS6]] to i64, !nosanitize
-    // CHECK-NEXT: call void @__ubsan_handle_type_mismatch
-    // CHECK-NOT: call void @__ubsan_handle_type_mismatch
-    (__extension__ (this))->foo = 0;
-    // CHECK: ret void
-  }
-
-  // CHECK-LABEL: define linkonce_odr void @_ZNK1A15assign_member_3Ev
-  void assign_member_3() const {
-    // CHECK: icmp ne %struct.A* %[[THIS7:[a-z0-9]+]], null, !nosanitize
-    // CHECK: ptrtoint %struct.A* %[[THIS7]] to i64, !nosanitize
-    // CHECK-NEXT: call void @__ubsan_handle_type_mismatch
-    // CHECK-NOT: call void @__ubsan_handle_type_mismatch
-    const_cast<A *>(this)->foo = 0;
-    // CHECK: ret void
-  }
-
-  // CHECK-LABEL: define linkonce_odr i32 @_ZN1A22call_through_referenceERS_
-  static int call_through_reference(A &a) {
-    // CHECK-NOT: call void @__ubsan_handle_type_mismatch
-    return a.load_member();
-    // CHECK: ret i32
-  }
-
-  // CHECK-LABEL: define linkonce_odr i32 @_ZN1A20call_through_pointerEPS_
-  static int call_through_pointer(A *a) {
-    // CHECK: call void @__ubsan_handle_type_mismatch
-    return a->load_member();
-    // CHECK: ret i32
-  }
-};
-
-struct B {
-  operator A*() const { return nullptr; }
-
-  // CHECK-LABEL: define linkonce_odr i32 @_ZN1B11load_memberEv
-  static int load_member() {
-    // Null-check &b before converting it to an A*.
-    // CHECK: call void @__ubsan_handle_type_mismatch
-    //
-    // Null-check the result of the conversion before using it.
-    // CHECK: call void @__ubsan_handle_type_mismatch
-    //
-    // CHECK-NOT: call void @__ubsan_handle_type_mismatch
-    B b;
-    return static_cast<A *>(b)->load_member();
-    // CHECK: ret i32
-  }
-};
-
-struct Base {
-  int foo;
-
-  virtual int load_member_1() = 0;
-};
-
-struct Derived : public Base {
-  int bar;
-
-  // CHECK-LABEL: define linkonce_odr i32 @_ZN7Derived13load_member_2Ev
-  int load_member_2() {
-    // CHECK: icmp ne %struct.Derived* %[[THIS8:[a-z0-9]+]], null, !nosanitize
-    // CHECK: ptrtoint %struct.Derived* %[[THIS8]] to i64, !nosanitize
-    // CHECK-NEXT: call void @__ubsan_handle_type_mismatch
-    //
-    // Null-check the result of the cast before using it.
-    // CHECK: call void @__ubsan_handle_type_mismatch
-    //
-    // CHECK-NOT: call void @__ubsan_handle_type_mismatch
-    return dynamic_cast<Base *>(this)->load_member_1();
-    // CHECK: ret i32
-  }
-
-  // CHECK-LABEL: define linkonce_odr i32 @_ZN7Derived13load_member_3Ev
-  int load_member_3() {
-    // CHECK: icmp ne %struct.Derived* %[[THIS9:[a-z0-9]+]], null, !nosanitize
-    // CHECK: ptrtoint %struct.Derived* %[[THIS9]] to i64, !nosanitize
-    // CHECK-NEXT: call void @__ubsan_handle_type_mismatch
-    // CHECK-NOT: call void @__ubsan_handle_type_mismatch
-    return reinterpret_cast<Derived *>(static_cast<Base *>(this))->foo;
-    // CHECK: ret i32
-  }
-
-  // CHECK-LABEL: define linkonce_odr i32 @_ZN7Derived13load_member_1Ev
-  int load_member_1() override {
-    // CHECK: icmp ne %struct.Derived* %[[THIS10:[a-z0-9]+]], null, !nosanitize
-    // CHECK: ptrtoint %struct.Derived* %[[THIS10]] to i64, !nosanitize
-    // CHECK-NEXT: call void @__ubsan_handle_type_mismatch
-    // CHECK-NOT: call void @__ubsan_handle_type_mismatch
-    return foo + bar;
-    // CHECK: ret i32
-  }
-};
-
-void force_irgen() {
-  A *a;
-  a->do_nothing();
-#ifdef CHECK_LAMBDA
-  a->do_nothing_with_lambda();
-#endif
-  a->load_member();
-  a->call_method();
-  a->assign_member_1();
-  a->assign_member_2();
-  a->assign_member_3();
-  A::call_through_reference(*a);
-  A::call_through_pointer(a);
-
-  B::load_member();
-
-  Base *b = new Derived;
-  b->load_member_1();
-
-  Derived *d;
-  d->load_member_2();
-  d->load_member_3();
-}

diff --git a/test/CodeGenCXX/ubsan-type-checks.cpp b/test/CodeGenCXX/ubsan-type-checks.cpp
index b2cd475a6cc2d23d925f434925c2708dcd0e9dd7..150b2fc40c251202e4d0df8f6ddf87a172e1c87c 100644 (file)
--- a/test/CodeGenCXX/ubsan-type-checks.cpp
+++ b/test/CodeGenCXX/ubsan-type-checks.cpp
@@ -5,8 +5,8 @@
 struct A {
   // COMMON-LABEL: define linkonce_odr void @_ZN1A10do_nothingEv
   void do_nothing() {
-    // ALIGN-NOT: ptrtoint %struct.A* %{{.*}} to i64, !nosanitize
-    // ALIGN-NOT: and i64 %{{.*}}, 7, !nosanitize
+    // ALIGN: ptrtoint %struct.A* %{{.*}} to i64, !nosanitize
+    // ALIGN: and i64 %{{.*}}, 0, !nosanitize
  
     // NULL: icmp ne %struct.A* %{{.*}}, null, !nosanitize