clang/test/CodeGenCXX/cxx2a-thread-local-constinit.cpp

   1 // RUN: %clang_cc1 -no-opaque-pointers -triple x86_64-linux-gnu -std=c++2a %s -emit-llvm -o - | FileCheck --check-prefix=CHECK --check-prefix=LINUX %s
   2 // RUN: %clang_cc1 -no-opaque-pointers -triple x86_64-apple-darwin12  -std=c++2a %s -emit-llvm -o - | FileCheck --check-prefix=CHECK --check-prefix=DARWIN %s
   3
   4 // Check variable definitions/declarations. Note that on Darwin, typically the
   5 // variable's symbol is marked internal, and only the _ZTW function is
   6 // exported. Except: constinit variables do get exported, even on darwin.
   7
   8 // CHECK-DAG:  @a = external thread_local global i32
   9 // CHECK-DAG:  @b = external thread_local global i32
  10 // LINUX-DAG:  @c ={{.*}} thread_local global i32 0, align 4
  11 // DARWIN-DAG: @c = internal thread_local global i32 0, align 4
  12 // LINUX-DAG:  @d ={{.*}} thread_local global i32 0, align 4
  13 // DARWIN-DAG: @d = internal thread_local global i32 0, align 4
  14 // CHECK-DAG:  @e = external thread_local global %struct.Destructed, align 4
  15 // CHECK-DAG:  @e2 ={{.*}} thread_local global %struct.Destructed zeroinitializer, align 4
  16 // CHECK-DAG:  @f ={{.*}} thread_local global i32 4, align 4
  17
  18 extern thread_local int a;
  19 extern thread_local constinit int b;
  20
  21 // CHECK-LABEL: define{{.*}} i32 @_Z5get_av()
  22 // CHECK: call {{(cxx_fast_tlscc )?}}i32* @_ZTW1a()
  23 // CHECK: }
  24 int get_a() { return a; }
  25
  26 // LINUX-LABEL: define linkonce_odr {{.*}} @_ZTW1a()
  27 // LINUX: br i1
  28 // LINUX: call void @_ZTH1a()
  29 // LINUX: }
  30 // DARWIN-NOT: define {{.*}}@_ZTW1a()
  31
  32 // CHECK-LABEL: define{{.*}} i32 @_Z5get_bv()
  33 // CHECK-NOT: call
  34 // CHECK: [[B_ADDR:%.+]] = call align 4 i32* @llvm.threadlocal.address.p0i32(i32* align 4 @b)
  35 // CHECK: load i32, i32* [[B_ADDR]]
  36 // CHECK-NOT: call
  37 // CHECK: }
  38 int get_b() { return b; }
  39
  40 // CHECK-NOT: define {{.*}} @_ZTW1b()
  41
  42 extern thread_local int c;
  43
  44 // CHECK-LABEL: define{{.*}} i32 @_Z5get_cv()
  45 // LINUX: call {{(cxx_fast_tlscc )?}}i32* @_ZTW1c()
  46 // CHECK: load i32, i32* %
  47 // CHECK: }
  48 int get_c() { return c; }
  49
  50 // Note: use of 'c' does not trigger initialization of 'd', because 'c' has a
  51 // constant initializer.
  52 // DARWIN-LABEL: define cxx_fast_tlscc {{.*}} @_ZTW1c()
  53 // LINUX-LABEL: define weak_odr {{.*}} @_ZTW1c()
  54 // CHECK-NOT: br i1
  55 // CHECK-NOT: call
  56 // CHECK: [[C_ADDR:%.+]] = call align 4 i32* @llvm.threadlocal.address.p0i32(i32* align 4 @c)
  57 // CHECK: ret i32* [[C_ADDR]]
  58 // CHECK: }
  59
  60 thread_local int c = 0;
  61
  62 // PR51079: We must assume an incomplete class type might have non-trivial
  63 // destruction, and so speculatively call the thread wrapper.
  64
  65 // CHECK-LABEL: define {{.*}} @_Z6get_e3v(
  66 // CHECK: call {{.*}}* @_ZTW2e3()
  67 // CHECK-LABEL: }
  68 extern thread_local constinit struct DestructedFwdDecl e3;
  69 DestructedFwdDecl &get_e3() { return e3; }
  70
  71 int d_init();
  72
  73 // CHECK: define {{.*}}[[D_INIT:@__cxx_global_var_init[^(]*]](
  74 // CHECK: call {{.*}} @_Z6d_initv()
  75 thread_local int d = d_init();
  76
  77 struct Destructed {
  78   int n = 0;
  79   ~Destructed();
  80 };
  81
  82 extern thread_local constinit Destructed e;
  83 // CHECK-LABEL: define{{.*}} i32 @_Z5get_ev()
  84 // CHECK: call {{.*}}* @_ZTW1e()
  85 // CHECK: }
  86 int get_e() { return e.n; }
  87
  88 // CHECK: define {{.*}}[[E2_INIT:@__cxx_global_var_init[^(]*]](
  89 // LINUX: call {{.*}} @__cxa_thread_atexit({{.*}} @_ZN10DestructedD1Ev {{.*}} @e2
  90 // DARWIN: call {{.*}} @_tlv_atexit({{.*}} @_ZN10DestructedD1Ev {{.*}} @e2
  91 thread_local constinit Destructed e2;
  92
  93 thread_local constinit int f = 4;
  94
  95 // CHECK-LABEL: define {{.*}}__tls_init
  96 // CHECK: call {{.*}} [[D_INIT]]
  97 // CHECK: call {{.*}} [[E2_INIT]]
  98
  99 // Because the call wrapper may be called speculatively (and simply because
 100 // it's required by the ABI), it must always be emitted for an external linkage
 101 // variable, even if the variable has constant initialization and constant
 102 // destruction.
 103 struct NotDestructed { int n = 0; };
 104 thread_local constinit NotDestructed nd;
 105 // CHECK-LABEL: define {{.*}} @_ZTW2nd