clang/test/CodeGenCXX/ubsan-type-checks.cpp

   1 // RUN: %clang_cc1 -std=c++11 -triple x86_64-apple-darwin10 -emit-llvm -o - %s -fsanitize=alignment | FileCheck %s -check-prefixes=ALIGN,COMMON
   2 // RUN: %clang_cc1 -std=c++11 -triple x86_64-apple-darwin10 -emit-llvm -o - %s -fsanitize=null | FileCheck %s -check-prefixes=NULL,COMMON
   3 // RUN: %clang_cc1 -std=c++11 -triple x86_64-apple-darwin10 -emit-llvm -o - %s -fsanitize=object-size | FileCheck %s -check-prefixes=OBJSIZE,COMMON
   4 // RUN: %clang_cc1 -std=c++11 -triple x86_64-apple-darwin10 -emit-llvm -o - %s -fsanitize=null,vptr | FileCheck %s -check-prefixes=VPTR
   5 // RUN: %clang_cc1 -std=c++11 -triple x86_64-apple-darwin10 -emit-llvm -o - %s -fsanitize=vptr | FileCheck %s -check-prefixes=VPTR_NO_NULL
   6
   7 struct A {
   8   // COMMON-LABEL: define linkonce_odr void @_ZN1A10do_nothingEv
   9   void do_nothing() {
  10     // ALIGN-NOT: ptrtoint %struct.A* %{{.*}} to i64, !nosanitize
  11
  12     // NULL: icmp ne %struct.A* %{{.*}}, null, !nosanitize
  13
  14     // OBJSIZE-NOT: call i64 @llvm.objectsize
  15   }
  16 };
  17
  18 struct B {
  19   int x;
  20
  21   // COMMON-LABEL: define linkonce_odr void @_ZN1B10do_nothingEv
  22   void do_nothing() {
  23     // ALIGN: ptrtoint %struct.B* %{{.*}} to i64, !nosanitize
  24     // ALIGN: and i64 %{{.*}}, 3, !nosanitize
  25
  26     // NULL: icmp ne %struct.B* %{{.*}}, null, !nosanitize
  27
  28     // OBJSIZE-NOT: call i64 @llvm.objectsize
  29     // OBJSIZE: ret void
  30   }
  31 };
  32
  33 struct Animal {
  34   virtual const char *speak() = 0;
  35 };
  36
  37 struct Cat : Animal {
  38   const char *speak() override { return "meow"; }
  39 };
  40
  41 struct Dog : Animal {
  42   const char *speak() override { return "woof"; }
  43 };
  44
  45 // VPTR-LABEL: define{{.*}} void @_Z12invalid_castP3Cat
  46 void invalid_cast(Cat *cat = nullptr) {
  47   // If -fsanitize=null is available, we'll reuse its check:
  48   //
  49   // VPTR: [[ICMP:%.*]] = icmp ne %struct.Dog* {{.*}}, null
  50   // VPTR-NEXT: br i1 [[ICMP]]
  51   // VPTR: call void @__ubsan_handle_type_mismatch
  52   // VPTR-NOT: icmp ne %struct.Dog* {{.*}}, null
  53   // VPTR: br i1 [[ICMP]]
  54   // VPTR: call void @__ubsan_handle_dynamic_type_cache_miss
  55   //
  56   // Fall back to the vptr sanitizer's null check when -fsanitize=null isn't
  57   // available.
  58   //
  59   // VPTR_NO_NULL-NOT: call void @__ubsan_handle_type_mismatch
  60   // VPTR_NO_NULL: [[ICMP:%.*]] = icmp ne %struct.Dog* {{.*}}, null
  61   // VPTR_NO_NULL-NEXT: br i1 [[ICMP]]
  62   // VPTR_NO_NULL: call void @__ubsan_handle_dynamic_type_cache_miss
  63   auto *badDog = reinterpret_cast<Dog *>(cat);
  64   badDog->speak();
  65 }
  66
  67 // VPTR_NO_NULL-LABEL: define{{.*}} void @_Z13invalid_cast2v
  68 void invalid_cast2() {
  69   // We've got a pointer to an alloca, so there's no run-time null check needed.
  70   // VPTR_NO_NULL-NOT: call void @__ubsan_handle_type_mismatch
  71   // VPTR_NO_NULL: call void @__ubsan_handle_dynamic_type_cache_miss
  72   Cat cat;
  73   cat.speak();
  74 }
  75
  76 int main() {
  77   A a;
  78   a.do_nothing();
  79
  80   B b;
  81   b.do_nothing();
  82
  83   invalid_cast();
  84   return 0;
  85 }