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      1 // RUN: %clang_cc1 -triple arm64-none-linux-gnu -emit-llvm -w -o - %s | FileCheck %s
      2 
      3 // Check differences between the generic Itanium ABI, the AArch32 version and
      4 // the AArch64 version.
      5 
      6 ////////////////////////////////////////////////////////////////////////////////
      7 
      8 // The ABI says that the key function is the "textually first, non-inline,
      9 // non-pure, virtual member function". The generic version decides this after
     10 // the completion of the class definition; the AArch32 version decides this at
     11 // the end of the translation unit.
     12 
     13 // We construct a class which needs a VTable here under generic ABI, but not
     14 // AArch32.
     15 
     16 // (see next section for explanation of guard)
     17 // CHECK: @_ZGVZ15guard_variablesiE4mine = internal global i64 0
     18 
     19 // CHECK: @_ZTV16CheckKeyFunction =
     20 struct CheckKeyFunction {
     21   virtual void foo();
     22 };
     23 
     24 // This is not inline when CheckKeyFunction is completed, so
     25 // CheckKeyFunction::foo is the key function. VTables should be emitted.
     26 inline void CheckKeyFunction::foo() {
     27 }
     28 
     29 ////////////////////////////////////////////////////////////////////////////////
     30 
     31 // Guard variables only specify and use the low bit to determine status, rather
     32 // than the low byte as in the generic Itanium ABI. However, unlike 32-bit ARM,
     33 // they *are* 64-bits wide so check that in case confusion has occurred.
     34 
     35 class Guarded {
     36 public:
     37   Guarded(int i);
     38   ~Guarded();
     39 };
     40 
     41 void guard_variables(int a) {
     42   static Guarded mine(a);
     43 // CHECK: [[GUARDBIT:%[0-9]+]] = and i8 {{%[0-9]+}}, 1
     44 // CHECK: icmp eq i8 [[GUARDBIT]], 0
     45 
     46   // As guards are 64-bit, these helpers should take 64-bit pointers.
     47 // CHECK: call i32 @__cxa_guard_acquire(i64*
     48 // CHECK: call void @__cxa_guard_release(i64*
     49 }
     50 
     51 ////////////////////////////////////////////////////////////////////////////////
     52 
     53 // Member function pointers use the adj field to distinguish between virtual and
     54 // nonvirtual members. As a result the adjustment is shifted (if ptr was used, a
     55 // mask would be expected instead).
     56 
     57 class C {
     58   int a();
     59   virtual int b();
     60 };
     61 
     62 
     63 int member_pointer(C &c, int (C::*func)()) {
     64 // CHECK: ashr i64 %[[MEMPTRADJ:[0-9a-z.]+]], 1
     65 // CHECK: %[[ISVIRTUAL:[0-9]+]] = and i64 %[[MEMPTRADJ]], 1
     66 // CHECK: icmp ne i64 %[[ISVIRTUAL]], 0
     67   return (c.*func)();
     68 }
     69 
     70 ////////////////////////////////////////////////////////////////////////////////
     71 
     72 // AArch64 PCS says that va_list type is based on "struct __va_list ..." in the
     73 // std namespace, which means it should mangle as "St9__va_list".
     74 
     75 // CHECK: @_Z7va_funcSt9__va_list
     76 void va_func(__builtin_va_list l) {
     77 }
     78 
     79 ////////////////////////////////////////////////////////////////////////////////
     80 
     81 // AArch64 constructors (like generic Itanium, but unlike AArch32) do not return
     82 // "this".
     83 
     84 void test_constructor() {
     85   Guarded g(42);
     86 // CHECK: call void @_ZN7GuardedC1Ei
     87 }
     88 
     89 ////////////////////////////////////////////////////////////////////////////////
     90 
     91 // In principle the AArch32 ABI allows this to be accomplished via a call to
     92 // __aeabi_atexit instead of __cxa_atexit. Clang doesn't make use of this at the
     93 // moment, but it's definitely not allowed for AArch64.
     94 
     95 // CHECK: call i32 @__cxa_atexit
     96 Guarded g(42);
     97