text: // RUN: %clang_cc1 -std=c++11 -S -emit-llvm -o - %s -triple x86_64-linux-gnu | FileCheck %s
  // RUN: %clang_cc1 -std=c++17 -S -emit-llvm -o - %s -triple x86_64-linux-gnu | FileCheck %s
  
  struct A { int a, b; int f(); };
  
  namespace NonAggregateCopyInAggregateInit { // PR32044
    struct A { constexpr A(int n) : x(n), y() {} int x, y; } extern a;
    // CHECK-DAG: @_ZN31NonAggregateCopyInAggregateInit1bE ={{.*}} global %{{.*}} { %[[A:.*]]* @_ZN31NonAggregateCopyInAggregateInit1aE }
    struct B { A &p; } b{{a}};
    // CHECK-DAG: @_ZGRN31NonAggregateCopyInAggregateInit1cE_ = internal global %[[A]] { i32 1, i32 0 }
    // CHECK-DAG: @_ZN31NonAggregateCopyInAggregateInit1cE ={{.*}} global %{{.*}} { %{{.*}}* @_ZGRN31NonAggregateCopyInAggregateInit1cE_ }
    struct C { A &&p; } c{{1}};
  }
  
  namespace NearlyZeroInit {
    // CHECK-DAG: @_ZN14NearlyZeroInit1aE ={{.*}} global {{.*}} <{ i32 1, i32 2, i32 3, [120 x i32] zeroinitializer }>
    int a[123] = {1, 2, 3};
    // CHECK-DAG: @_ZN14NearlyZeroInit1bE ={{.*}} global {{.*}} { i32 1, <{ i32, [2147483647 x i32] }> <{ i32 2, [2147483647 x i32] zeroinitializer }> }
    struct B { int n; int arr[1024 * 1024 * 1024 * 2u]; } b = {1, {2}};
  }
  
  namespace PR37560 {
    union U {
      char x;
      int a;
    };
    // FIXME: [dcl.init]p2, the padding bits of the union object should be
    // initialized to 0, not undef, which would allow us to collapse the tail
    // of these arrays to zeroinitializer.
    // CHECK-DAG: @_ZN7PR375601cE ={{.*}} global <{ { i8, [3 x i8] } }> <{ { i8, [3 x i8] } { i8 0, [3 x i8] undef } }>
    U c[1] = {};
    // CHECK-DAG: @_ZN7PR375601dE ={{.*}} global {{.*}} <{ { i8, [3 x i8] } { i8 97, [3 x i8] undef }, %"{{[^"]*}}" { i32 123 }, { i8, [3 x i8] } { i8 98, [3 x i8] undef }, { i8, [3 x i8] } { i8 0, [3 x i8] undef },
    U d[16] = {'a', {.a = 123}, 'b'};
    // CHECK-DAG: @_ZN7PR375601eE ={{.*}} global {{.*}} <{ %"{{[^"]*}}" { i32 123 }, %"{{[^"]*}}" { i32 456 }, { i8, [3 x i8] } { i8 0, [3 x i8] undef },
    U e[16] = {{.a = 123}, {.a = 456}};
  
    union V {
      int a;
      char x;
    };
    // CHECK-DAG: @_ZN7PR375601fE ={{.*}} global [1 x %"{{[^"]*}}"] zeroinitializer
    V f[1] = {};
    // CHECK-DAG: @_ZN7PR375601gE ={{.*}} global {{.*}} <{ { i8, [3 x i8] } { i8 97, [3 x i8] undef }, %"{{[^"]*}}" { i32 123 }, { i8, [3 x i8] } { i8 98, [3 x i8] undef }, [13 x %"{{[^"]*}}"] zeroinitializer }>
    V g[16] = {{.x = 'a'}, {.a = 123}, {.x = 'b'}};
    // CHECK-DAG: @_ZN7PR375601hE ={{.*}} global {{.*}} <{ %"{{[^"]*}}" { i32 123 }, %"{{[^"]*}}" { i32 456 }, [14 x %"{{[^"]*}}"] zeroinitializer }>
    V h[16] = {{.a = 123}, {.a = 456}};
    // CHECK-DAG: @_ZN7PR375601iE ={{.*}} global [4 x %"{{[^"]*}}"] [%"{{[^"]*}}" { i32 123 }, %"{{[^"]*}}" { i32 456 }, %"{{[^"]*}}" zeroinitializer, %"{{[^"]*}}" zeroinitializer]
    V i[4] = {{.a = 123}, {.a = 456}};
  }
  
  // CHECK-LABEL: define {{.*}}@_Z3fn1i(
  int fn1(int x) {
    // CHECK: %[[INITLIST:.*]] = alloca %struct.A
    // CHECK: %[[A:.*]] = getelementptr inbounds %struct.A, %struct.A* %[[INITLIST]], i32 0, i32 0
    // CHECK: store i32 %{{.*}}, i32* %[[A]], align 4
    // CHECK: %[[B:.*]] = getelementptr inbounds %struct.A, %struct.A* %[[INITLIST]], i32 0, i32 1
    // CHECK: store i32 5, i32* %[[B]], align 4
    // CHECK: call noundef i32 @_ZN1A1fEv(%struct.A* {{[^,]*}} %[[INITLIST]])
    return A{x, 5}.f();
  }
  
  struct B { int &r; int &f() { return r; } };
  
  // CHECK-LABEL: define {{.*}}@_Z3fn2Ri(
  int &fn2(int &v) {
    // CHECK: %[[INITLIST2:.*]] = alloca %struct.B, align 8
    // CHECK: %[[R:.*]] = getelementptr inbounds %struct.B, %struct.B* %[[INITLIST2:.*]], i32 0, i32 0
    // CHECK: store i32* %{{.*}}, i32** %[[R]], align 8
    // CHECK: call noundef nonnull align {{[0-9]+}} dereferenceable({{[0-9]+}}) i32* @_ZN1B1fEv(%struct.B* {{[^,]*}} %[[INITLIST2:.*]])
    return B{v}.f();
  }
  
  // CHECK-LABEL: define {{.*}}@__cxx_global_var_init(
  //
  // CHECK: call {{.*}}@_ZN14NonTrivialInit1AC1Ev(
  // CHECK: getelementptr inbounds {{.*}}, i64 1
  // CHECK: br i1
  //
  // CHECK: getelementptr inbounds {{.*}}, i64 1
  // CHECK: icmp eq {{.*}}, getelementptr inbounds {{.*}}, i64 1, i64 0
  // CHECK: br i1
  //
  // CHECK: call i32 @__cxa_atexit(
  namespace NonTrivialInit {
    struct A { A(); A(const A&) = delete; ~A(); };
    struct B { A a[20]; };
    // NB, this must be large enough to be worth memsetting for this test to be
    // meaningful.
    B b[30] = {};
  }
  
  namespace ZeroInit {
    enum { Zero, One };
    constexpr int zero() { return 0; }
    constexpr int *null() { return nullptr; }
    struct Filler {
      int x;
      Filler();
    };
    struct S1 {
      int x;
    };
  
    // These declarations, if implemented elementwise, require huge
    // amout of memory and compiler time.
    unsigned char data_1[1024 * 1024 * 1024 * 2u] = { 0 };
    unsigned char data_2[1024 * 1024 * 1024 * 2u] = { Zero };
    unsigned char data_3[1024][1024][1024] = {{{0}}};
    unsigned char data_4[1024 * 1024 * 1024 * 2u] = { zero() };
    int *data_5[1024 * 1024 * 512] = { nullptr };
    int *data_6[1024 * 1024 * 512] = { null() };
    struct S1 data_7[1024 * 1024 * 512] = {{0}};
    char data_8[1000 * 1000 * 1000] = {};
    int (&&data_9)[1000 * 1000 * 1000] = {0};
    unsigned char data_10[1024 * 1024 * 1024 * 2u] = { 1 };
    unsigned char data_11[1024 * 1024 * 1024 * 2u] = { One };
    unsigned char data_12[1024][1024][1024] = {{{1}}};
  
    // This variable must be initialized elementwise.
    Filler data_e1[1024] = {};
    // CHECK: getelementptr inbounds {{.*}} @_ZN8ZeroInit7data_e1E
  
    struct Largeish {
      long a, b, c;
    };
    // CHECK: define {{.*}}@_ZN8ZeroInit9largeish1Ev(
    // CHECK-NOT }
    // CHECK: call {{.*}}memset
    Largeish largeish1() { return {}; }
    // CHECK: define {{.*}}@_ZN8ZeroInit9largeish2Ev(
    // CHECK-NOT }
    // CHECK: call {{.*}}memset
    Largeish largeish2() { return Largeish(); }
    // CHECK: define {{.*}}@_ZN8ZeroInit9largeish3Ev(
    // CHECK-NOT }
    // CHECK: call {{.*}}memset
    Largeish largeish3() { return Largeish{}; }
    // CHECK: define {{.*}}@_ZN8ZeroInit9largeish4Ev(
    // CHECK-NOT }
    // CHECK: call {{.*}}memset
    Largeish largeish4() { return (Largeish){}; }
    // CHECK: define {{.*}}@_ZN8ZeroInit9largeish5Ev(
    // CHECK-NOT }
    // CHECK: call {{.*}}memset
    Largeish largeish5() { return {0, 0, 0}; }
  
    typedef __attribute__((ext_vector_type(4))) char CI4;
    struct Conversions {
      _Complex int a;
      _Complex float b;
      short c;
      long double d;
      CI4 e;
      char f;
      char g;
      int *h;
      long i;
    };
    // CHECK: define {{.*}}@_ZN8ZeroInit11conversionsEv(
    // CHECK-NOT }
    // CHECK: call {{.*}}memset
    Conversions conversions() {
      return {0,
              0,
              0,
              0,
              CI4(0),
              static_cast<char>(0.0),
              char(0 + 0i),
              reinterpret_cast<int *>(0),
              reinterpret_cast<long>((int *)nullptr)};
    }
  }
  