TheRock/compiler/amd-llvm/clang/test/Sema/attr-overflow-behavior-templates.cpp

// RUN: %clang_cc1 %s -fexperimental-overflow-behavior-types -verify -fsyntax-only -Wimplicit-overflow-behavior-conversion
// RUN: %clang_cc1 %s -fexperimental-overflow-behavior-types -verify -fsyntax-only -Wimplicit-overflow-behavior-conversion -fexperimental-new-constant-interpreter

template<typename T>
constexpr int template_overload_test(T) {
  return 10;
}

constexpr int template_overload_test(int) {
  return 20;
}

constexpr int template_overload_test(__ob_wrap int) {
  return 30;
}

constexpr int template_overload_test(__ob_trap int) {
  return 40;
}

void test_template_overload_resolution() {
  static_assert(template_overload_test(42) == 20, "int should pick int overload");
  static_assert(template_overload_test((__ob_wrap int)42) == 30, "__ob_wrap int should pick __ob_wrap int overload");
  static_assert(template_overload_test((__ob_trap int)42) == 40, "__ob_trap int should pick __ob_trap int overload");
}

template<typename T>
struct MultiSpecTester {
  static constexpr int value = 0;
};

template<>
struct MultiSpecTester<int> {
  static constexpr int value = 1;
};

void test_choosing_generic_when_only_underlying_present() {
  static_assert(MultiSpecTester<int>::value == 1, "int should match int specialization");
  // OBTs don't choose template specialization based on underlying type, they should go with the generic
  static_assert(MultiSpecTester<__ob_wrap int>::value == 0, "__ob_wrap int should match generic when there isn't a __ob_wrap specialization");
  static_assert(MultiSpecTester<__ob_trap int>::value == 0, "__ob_trap int should match generic when there isn't a __ob_trap specialization");
}

template<typename T = int>
constexpr int only_int_template(int value) {
  return value + 100;
}

void test_template_conversion_fallback() {
  static_assert(only_int_template<int>(42) == 142, "int direct match should work");
  // expected-warning@+1 {{passing argument of type '__ob_wrap int' to parameter of type 'int' discards overflow behavior at function boundary}}
  static_assert(only_int_template<int>((__ob_wrap int)42) == 142, "__ob_wrap int implicit conversion should work");
  // expected-warning@+1 {{passing argument of type '__ob_trap int' to parameter of type 'int' discards overflow behavior at function boundary}}
  static_assert(only_int_template<int>((__ob_trap int)42) == 142, "__ob_trap int implicit conversion should work");
}

void simple_overload_test(int);
void simple_overload_test(__ob_wrap int);

template<typename T>
void simple_overload_test(T) {}

void test_function_vs_template_overload() {
  int regular = 42;
  __ob_wrap int wrapped = 42;
  __ob_trap int trap = 42;

  simple_overload_test(regular);
  simple_overload_test(wrapped);
  simple_overload_test(trap);
}