clang/test/CodeGenCXX/static-data-member.cpp

   1 // RUN: %clang_cc1 -triple x86_64-pc-linux -emit-llvm -o - %s | FileCheck %s
   2 // RUN: %clang_cc1 -triple x86_64-apple-darwin -emit-llvm -o - %s | \
   3 // RUN: FileCheck --check-prefix=MACHO %s
   4
   5 // CHECK: @_ZN5test11A1aE ={{.*}} constant i32 10, align 4
   6 // CHECK: @_ZN5test212_GLOBAL__N_11AIiE1xE = internal global i32 0, align 4
   7 // CHECK: @_ZN5test31AIiE1xE = weak_odr global i32 0, comdat, align 4
   8 // CHECK: @_ZGVN5test31AIiE1xE = weak_odr global i64 0, comdat($_ZN5test31AIiE1xE)
   9 // MACHO: @_ZGVN5test31AIiE1xE = weak_odr global i64 0
  10 // MACHO-NOT: comdat
  11
  12 // CHECK: _ZN5test51U2k0E ={{.*}} global i32 0
  13 // CHECK: _ZN5test51U2k1E ={{.*}} global i32 0
  14 // CHECK: _ZN5test51U2k2E ={{.*}} constant i32 76
  15 // CHECK-NOT: test51U2k3E
  16 // CHECK-NOT: test51U2k4E
  17
  18 // PR5564.
  19 namespace test1 {
  20   struct A {
  21     static const int a = 10;
  22   };
  23
  24   const int A::a;
  25
  26   struct S {
  27     static int i;
  28   };
  29
  30   void f() {
  31     int a = S::i;
  32   }
  33 }
  34
  35 // Test that we don't use guards for initializing template static data
  36 // members with internal linkage.
  37 namespace test2 {
  38   int foo();
  39
  40   namespace {
  41     template <class T> struct A {
  42       static int x;
  43     };
  44
  45     template <class T> int A<T>::x = foo();
  46     template struct A<int>;
  47   }
  48
  49   // CHECK-LABEL: define internal void @__cxx_global_var_init()
  50   // CHECK:      [[TMP:%.*]] = call noundef i32 @_ZN5test23fooEv()
  51   // CHECK-NEXT: store i32 [[TMP]], ptr @_ZN5test212_GLOBAL__N_11AIiE1xE, align 4
  52   // CHECK-NEXT: ret void
  53 }
  54
  55 // Test that we don't use threadsafe statics when initializing
  56 // template static data members.
  57 namespace test3 {
  58   int foo();
  59
  60   template <class T> struct A {
  61     static int x;
  62   };
  63
  64   template <class T> int A<T>::x = foo();
  65   template struct A<int>;
  66
  67   // CHECK-LABEL: define internal void @__cxx_global_var_init.1() {{.*}} comdat($_ZN5test31AIiE1xE)
  68   // MACHO-LABEL: define internal void @__cxx_global_var_init.1()
  69   // MACHO-NOT: comdat
  70   // CHECK:      [[GUARDBYTE:%.*]] = load i8, ptr @_ZGVN5test31AIiE1xE
  71   // CHECK-NEXT: [[UNINITIALIZED:%.*]] = icmp eq i8 [[GUARDBYTE]], 0
  72   // CHECK-NEXT: br i1 [[UNINITIALIZED]]
  73   // CHECK:      store i8 1, ptr @_ZGVN5test31AIiE1xE
  74   // CHECK-NEXT: [[TMP:%.*]] = call noundef i32 @_ZN5test33fooEv()
  75   // CHECK-NEXT: store i32 [[TMP]], ptr @_ZN5test31AIiE1xE, align 4
  76   // CHECK-NEXT: br label
  77   // CHECK:      ret void
  78 }
  79
  80 // Test that we can fold member lookup expressions which resolve to static data
  81 // members.
  82 namespace test4 {
  83   struct A {
  84     static const int n = 76;
  85   };
  86
  87   int f(A *a) {
  88     // CHECK-LABEL: define{{.*}} i32 @_ZN5test41fEPNS_1AE
  89     // CHECK: ret i32 76
  90     return a->n;
  91   }
  92 }
  93
  94 // Test that static data members in unions behave properly.
  95 namespace test5 {
  96   union U {
  97     static int k0;
  98     static const int k1;
  99     static const int k2 = 76;
 100     static const int k3;
 101     static const int k4 = 81;
 102   };
 103   int U::k0;
 104   const int U::k1 = (k0 = 9, 42);
 105   const int U::k2;
 106
 107   // CHECK: store i32 9, ptr @_ZN5test51U2k0E
 108   // CHECK: store i32 {{.*}}, ptr @_ZN5test51U2k1E
 109   // CHECK-NOT: store {{.*}} ptr @_ZN5test51U2k2E
 110 }