clang/test/SemaCXX/builtin_vectorelements.cpp

   1 // RUN: %clang_cc1 -triple x86_64                       -std=c++20 -fsyntax-only -verify -disable-llvm-passes %s
   2
   3 // REQUIRES: aarch64-registered-target
   4 // RUN: %clang_cc1 -triple aarch64 -target-feature +sve -std=c++20 -fsyntax-only -verify -disable-llvm-passes %s
   5
   6 template <typename T>
   7 using VecT __attribute__((vector_size(16))) = T;
   8
   9 struct FooT {
  10   template <typename T>
  11   using VecT __attribute__((vector_size(8))) = T;
  12 };
  13
  14 void test_builtin_vectorelements() {
  15   using veci4 __attribute__((vector_size(16))) = int;
  16   (void) __builtin_vectorelements(veci4);
  17
  18   using some_other_vec = veci4;
  19   (void) __builtin_vectorelements(some_other_vec);
  20
  21   using some_int = int;
  22   (void) __builtin_vectorelements(some_int); // expected-error {{argument to __builtin_vectorelements must be of vector type}}
  23
  24   class Foo {};
  25   __builtin_vectorelements(Foo); // expected-error {{argument to __builtin_vectorelements must be of vector type}}
  26
  27   struct Bar { veci4 vec; };
  28   (void) __builtin_vectorelements(Bar{}.vec);
  29
  30   struct Baz { using VecT = veci4; };
  31   (void) __builtin_vectorelements(Baz::VecT);
  32
  33   (void) __builtin_vectorelements(FooT::VecT<long>);
  34   (void) __builtin_vectorelements(VecT<char>);
  35
  36   constexpr int i4 = __builtin_vectorelements(veci4);
  37   constexpr int i4p8 = __builtin_vectorelements(veci4) + 8;
  38 }
  39
  40
  41 #if defined(__ARM_FEATURE_SVE)
  42 #include <arm_sve.h>
  43
  44 consteval int consteval_elements() { // expected-error {{consteval function never produces a constant expression}}
  45   return __builtin_vectorelements(svuint64_t); // expected-note {{cannot determine number of elements for sizeless vectors in a constant expression}}  // expected-note {{cannot determine number of elements for sizeless vectors in a constant expression}} // expected-note {{cannot determine number of elements for sizeless vectors in a constant expression}}
  46 }
  47
  48 void test_bad_constexpr() {
  49   constexpr int eval = consteval_elements(); // expected-error {{initialized by a constant expression}} // expected-error {{not a constant expression}} // expected-note {{in call}} // expected-note {{in call}}
  50   constexpr int i32 = __builtin_vectorelements(svuint32_t); // expected-error {{initialized by a constant expression}} // expected-note {{cannot determine number of elements for sizeless vectors in a constant expression}}
  51   constexpr int i16p8 = __builtin_vectorelements(svuint16_t) + 16; // expected-error {{initialized by a constant expression}} // expected-note {{cannot determine number of elements for sizeless vectors in a constant expression}}
  52   constexpr int lambda = [] { return __builtin_vectorelements(svuint16_t); }(); // expected-error {{initialized by a constant expression}} // expected-note {{cannot determine number of elements for sizeless vectors in a constant expression}} // expected-note {{in call}}
  53 }
  54
  55 #endif