| // C++-specific checks for the alignment builtins |
| // RUN: %clang_cc1 -triple=x86_64-unknown-unknown -std=c++11 %s -fsyntax-only -verify=expected,both -fexperimental-new-constant-interpreter |
| // RUN: %clang_cc1 -triple=x86_64-unknown-unknown -std=c++11 %s -fsyntax-only -verify=ref,both |
| |
| // Check that we don't crash when using dependent types in __builtin_align: |
| template <typename a, a b> |
| void *c(void *d) { // both-note{{candidate template ignored}} |
| return __builtin_align_down(d, b); |
| } |
| |
| struct x {}; |
| x foo; |
| void test(void *value) { |
| c<int, 16>(value); |
| c<struct x, foo>(value); // both-error{{no matching function for call to 'c'}} |
| } |
| |
| template <typename T, long Alignment, long ArraySize = 16> |
| void test_templated_arguments() { |
| T array[ArraySize]; // both-error{{variable has incomplete type 'fwddecl'}} |
| static_assert(__is_same(decltype(__builtin_align_up(array, Alignment)), T *), // both-error{{requested alignment is not a power of 2}} |
| "return type should be the decayed array type"); |
| static_assert(__is_same(decltype(__builtin_align_down(array, Alignment)), T *), |
| "return type should be the decayed array type"); |
| static_assert(__is_same(decltype(__builtin_is_aligned(array, Alignment)), bool), |
| "return type should be bool"); |
| T *x1 = __builtin_align_up(array, Alignment); |
| T *x2 = __builtin_align_down(array, Alignment); |
| bool x3 = __builtin_align_up(array, Alignment); |
| } |
| |
| void test() { |
| test_templated_arguments<int, 32>(); // fine |
| test_templated_arguments<struct fwddecl, 16>(); |
| // both-note@-1{{in instantiation of function template specialization 'test_templated_arguments<fwddecl, 16L, 16L>'}} |
| // both-note@-2{{forward declaration of 'fwddecl'}} |
| test_templated_arguments<int, 7>(); // invalid alignment value |
| // both-note@-1{{in instantiation of function template specialization 'test_templated_arguments<int, 7L, 16L>'}} |
| } |
| |
| template <typename T, long ArraySize> |
| void test_incorrect_alignment_without_instatiation(T value) { |
| int array[32]; |
| static_assert(__is_same(decltype(__builtin_align_up(array, 31)), int *), // both-error{{requested alignment is not a power of 2}} |
| "return type should be the decayed array type"); |
| static_assert(__is_same(decltype(__builtin_align_down(array, 7)), int *), // both-error{{requested alignment is not a power of 2}} |
| "return type should be the decayed array type"); |
| static_assert(__is_same(decltype(__builtin_is_aligned(array, -1)), bool), // both-error{{requested alignment must be 1 or greater}} |
| "return type should be bool"); |
| __builtin_align_up(array); // both-error{{too few arguments to function call, expected 2, have 1}} |
| __builtin_align_up(array, 31); // both-error{{requested alignment is not a power of 2}} |
| __builtin_align_down(array, 31); // both-error{{requested alignment is not a power of 2}} |
| __builtin_align_up(array, 31); // both-error{{requested alignment is not a power of 2}} |
| __builtin_align_up(value, 31); // This shouldn't want since the type is dependent |
| __builtin_align_up(value); // Same here |
| |
| __builtin_align_up(array, sizeof(sizeof(value)) - 1); // both-error{{requested alignment is not a power of 2}} |
| __builtin_align_up(array, value); // no diagnostic as the alignment is value dependent. |
| (void)__builtin_align_up(array, ArraySize); // The same above here |
| } |
| |
| // The original fix for the issue above broke some legitimate code. |
| // Here is a regression test: |
| typedef __SIZE_TYPE__ size_t; |
| void *allocate_impl(size_t size); |
| template <typename T> |
| T *allocate() { |
| constexpr size_t allocation_size = |
| __builtin_align_up(sizeof(T), sizeof(void *)); |
| return static_cast<T *>( |
| __builtin_assume_aligned(allocate_impl(allocation_size), sizeof(void *))); |
| } |
| struct Foo { |
| int value; |
| }; |
| void *test2() { |
| return allocate<struct Foo>(); |
| } |
| |
| // Check that pointers-to-members cannot be used: |
| class MemPtr { |
| public: |
| int data; |
| void func(); |
| virtual void vfunc(); |
| }; |
| void test_member_ptr() { |
| __builtin_align_up(&MemPtr::data, 64); // both-error{{operand of type 'int MemPtr::*' where arithmetic or pointer type is required}} |
| __builtin_align_down(&MemPtr::func, 64); // both-error{{operand of type 'void (MemPtr::*)()' where arithmetic or pointer type is required}} |
| __builtin_is_aligned(&MemPtr::vfunc, 64); // both-error{{operand of type 'void (MemPtr::*)()' where arithmetic or pointer type is required}} |
| } |
| |
| void test_references(Foo &i) { |
| // Check that the builtins look at the referenced type rather than the reference itself. |
| (void)__builtin_align_up(i, 64); // both-error{{operand of type 'Foo' where arithmetic or pointer type is required}} |
| (void)__builtin_align_up(static_cast<Foo &>(i), 64); // both-error{{operand of type 'Foo' where arithmetic or pointer type is required}} |
| (void)__builtin_align_up(static_cast<const Foo &>(i), 64); // both-error{{operand of type 'const Foo' where arithmetic or pointer type is required}} |
| (void)__builtin_align_up(static_cast<Foo &&>(i), 64); // both-error{{operand of type 'Foo' where arithmetic or pointer type is required}} |
| (void)__builtin_align_up(static_cast<const Foo &&>(i), 64); // both-error{{operand of type 'const Foo' where arithmetic or pointer type is required}} |
| (void)__builtin_align_up(&i, 64); |
| } |
| |
| // Check that constexpr wrapper functions can be constant-evaluated. |
| template <typename T> |
| constexpr bool wrap_is_aligned(T ptr, long align) { |
| return __builtin_is_aligned(ptr, align); |
| // both-note@-1{{requested alignment -3 is not a positive power of two}} |
| // both-note@-2{{requested alignment 19 is not a positive power of two}} |
| // both-note@-3{{requested alignment must be 128 or less for type 'char'; 4194304 is invalid}} |
| } |
| template <typename T> |
| constexpr T wrap_align_up(T ptr, long align) { |
| return __builtin_align_up(ptr, align); |
| // both-note@-1{{requested alignment -2 is not a positive power of two}} |
| // both-note@-2{{requested alignment 18 is not a positive power of two}} |
| // both-note@-3{{requested alignment must be 2147483648 or less for type 'int'; 8589934592 is invalid}} |
| // both-error@-4{{operand of type 'bool' where arithmetic or pointer type is required}} |
| } |
| |
| template <typename T> |
| constexpr T wrap_align_down(T ptr, long align) { |
| return __builtin_align_down(ptr, align); |
| // both-note@-1{{requested alignment -1 is not a positive power of two}} |
| // both-note@-2{{requested alignment 17 is not a positive power of two}} |
| // both-note@-3{{requested alignment must be 32768 or less for type 'short'; 1048576 is invalid}} |
| } |
| |
| constexpr int a1 = wrap_align_up(22, 32); |
| static_assert(a1 == 32, ""); |
| constexpr int a2 = wrap_align_down(22, 16); |
| static_assert(a2 == 16, ""); |
| constexpr bool a3 = wrap_is_aligned(22, 32); |
| static_assert(!a3, ""); |
| static_assert(wrap_align_down(wrap_align_up(22, 16), 32) == 32, ""); |
| static_assert(wrap_is_aligned(wrap_align_down(wrap_align_up(22, 16), 32), 32), ""); |
| static_assert(!wrap_is_aligned(wrap_align_down(wrap_align_up(22, 16), 32), 64), ""); |
| |
| constexpr long const_value(long l) { return l; } |
| // Check some invalid values during constant-evaluation |
| static_assert(wrap_align_down(1, const_value(-1)), ""); // both-error{{not an integral constant expression}} |
| // both-note@-1{{in call to}} |
| static_assert(wrap_align_up(1, const_value(-2)), ""); // both-error{{not an integral constant expression}} |
| // both-note@-1{{in call to}} |
| static_assert(wrap_is_aligned(1, const_value(-3)), ""); // both-error{{not an integral constant expression}} |
| // both-note@-1{{in call to}} |
| static_assert(wrap_align_down(1, const_value(17)), ""); // both-error{{not an integral constant expression}} |
| // both-note@-1{{in call to}} |
| static_assert(wrap_align_up(1, const_value(18)), ""); // both-error{{not an integral constant expression}} |
| // both-note@-1{{in call to}} |
| static_assert(wrap_is_aligned(1, const_value(19)), ""); // both-error{{not an integral constant expression}} |
| // both-note@-1{{in call to}} |
| |
| // Check invalid values for smaller types: |
| static_assert(wrap_align_down(static_cast<short>(1), const_value(1 << 20)), ""); // both-error{{not an integral constant expression}} |
| // both-note@-1{{in call to }} |
| // Check invalid boolean type |
| static_assert(wrap_align_up(static_cast<int>(1), const_value(1ull << 33)), ""); // both-error{{not an integral constant expression}} |
| // both-note@-1{{in call to}} |
| static_assert(wrap_is_aligned(static_cast<char>(1), const_value(1 << 22)), ""); // both-error{{not an integral constant expression}} |
| // both-note@-1{{in call to}} |
| |
| // Check invalid boolean type |
| static_assert(wrap_align_up(static_cast<bool>(1), const_value(1 << 21)), ""); // both-error{{not an integral constant expression}} |
| // both-note@-1{{in instantiation of function template specialization 'wrap_align_up<bool>' requested here}} |
| |
| // Check constant evaluation for pointers: |
| _Alignas(32) char align32array[128]; |
| static_assert(&align32array[0] == &align32array[0], ""); |
| // __builtin_align_up/down can be constant evaluated as a no-op for values |
| // that are known to have greater alignment: |
| static_assert(__builtin_align_up(&align32array[0], 32) == &align32array[0], ""); |
| static_assert(__builtin_align_up(&align32array[0], 4) == &align32array[0], ""); |
| static_assert(__builtin_align_down(&align32array[0], 4) == __builtin_align_up(&align32array[0], 8), ""); |
| // But it can not be evaluated if the alignment is greater than the minimum |
| // known alignment, since in that case the value might be the same if it happens |
| // to actually be aligned to 64 bytes at run time. |
| static_assert(&align32array[0] == __builtin_align_up(&align32array[0], 64), ""); // both-error{{not an integral constant expression}} |
| // both-note@-1{{cannot constant evaluate the result of adjusting alignment to 64}} |
| static_assert(__builtin_align_up(&align32array[0], 64) == __builtin_align_up(&align32array[0], 64), ""); // both-error{{not an integral constant expression}} |
| // both-note@-1{{cannot constant evaluate the result of adjusting alignment to 64}} |
| |
| // However, we can compute in case the requested alignment is less than the |
| // base alignment: |
| static_assert(__builtin_align_up(&align32array[0], 4) == &align32array[0], ""); |
| static_assert(__builtin_align_up(&align32array[1], 4) == &align32array[4], ""); |
| static_assert(__builtin_align_up(&align32array[2], 4) == &align32array[4], ""); |
| static_assert(__builtin_align_up(&align32array[3], 4) == &align32array[4], ""); |
| static_assert(__builtin_align_up(&align32array[4], 4) == &align32array[4], ""); |
| static_assert(__builtin_align_up(&align32array[5], 4) == &align32array[8], ""); |
| static_assert(__builtin_align_up(&align32array[6], 4) == &align32array[8], ""); |
| static_assert(__builtin_align_up(&align32array[7], 4) == &align32array[8], ""); |
| static_assert(__builtin_align_up(&align32array[8], 4) == &align32array[8], ""); |
| |
| static_assert(__builtin_align_down(&align32array[0], 4) == &align32array[0], ""); |
| static_assert(__builtin_align_down(&align32array[1], 4) == &align32array[0], ""); |
| static_assert(__builtin_align_down(&align32array[2], 4) == &align32array[0], ""); |
| static_assert(__builtin_align_down(&align32array[3], 4) == &align32array[0], ""); |
| static_assert(__builtin_align_down(&align32array[4], 4) == &align32array[4], ""); |
| static_assert(__builtin_align_down(&align32array[5], 4) == &align32array[4], ""); |
| static_assert(__builtin_align_down(&align32array[6], 4) == &align32array[4], ""); |
| static_assert(__builtin_align_down(&align32array[7], 4) == &align32array[4], ""); |
| static_assert(__builtin_align_down(&align32array[8], 4) == &align32array[8], ""); |
| |
| // Achieving the same thing using casts to uintptr_t is not allowed: |
| static_assert((char *)((__UINTPTR_TYPE__)&align32array[7] & ~3) == &align32array[4], ""); // both-error{{not an integral constant expression}} |
| |
| static_assert(__builtin_align_down(&align32array[1], 4) == &align32array[0], ""); |
| static_assert(__builtin_align_down(&align32array[1], 64) == &align32array[0], ""); // both-error{{not an integral constant expression}} |
| // both-note@-1{{cannot constant evaluate the result of adjusting alignment to 64}} |
| |
| // Add some checks for __builtin_is_aligned: |
| static_assert(__builtin_is_aligned(&align32array[0], 32), ""); |
| static_assert(__builtin_is_aligned(&align32array[4], 4), ""); |
| // We cannot constant evaluate whether the array is aligned to > 32 since this |
| // may well be true at run time. |
| static_assert(!__builtin_is_aligned(&align32array[0], 64), ""); // both-error{{not an integral constant expression}} |
| // both-note@-1{{cannot constant evaluate whether run-time alignment is at least 64}} |
| |
| // However, if the alignment being checked is less than the minimum alignment of |
| // the base object we can check the low bits of the alignment: |
| static_assert(__builtin_is_aligned(&align32array[0], 4), ""); |
| static_assert(!__builtin_is_aligned(&align32array[1], 4), ""); |
| static_assert(!__builtin_is_aligned(&align32array[2], 4), ""); |
| static_assert(!__builtin_is_aligned(&align32array[3], 4), ""); |
| static_assert(__builtin_is_aligned(&align32array[4], 4), ""); |
| |
| // TODO: this should evaluate to true even though we can't evaluate the result |
| // of __builtin_align_up() to a concrete value |
| static_assert(__builtin_is_aligned(__builtin_align_up(&align32array[0], 64), 64), ""); // both-error{{not an integral constant expression}} |
| // both-note@-1{{cannot constant evaluate the result of adjusting alignment to 64}} |
| |
| // Check different source and alignment type widths are handled correctly. |
| static_assert(!__builtin_is_aligned(static_cast<signed long>(7), static_cast<signed short>(4)), ""); |
| static_assert(!__builtin_is_aligned(static_cast<signed short>(7), static_cast<signed long>(4)), ""); |
| // Also check signed -- unsigned mismatch. |
| static_assert(!__builtin_is_aligned(static_cast<signed long>(7), static_cast<signed long>(4)), ""); |
| static_assert(!__builtin_is_aligned(static_cast<unsigned long>(7), static_cast<unsigned long>(4)), ""); |
| static_assert(!__builtin_is_aligned(static_cast<signed long>(7), static_cast<unsigned long>(4)), ""); |
| static_assert(!__builtin_is_aligned(static_cast<unsigned long>(7), static_cast<signed long>(4)), ""); |
| static_assert(!__builtin_is_aligned(static_cast<signed long>(7), static_cast<unsigned short>(4)), ""); |
| static_assert(!__builtin_is_aligned(static_cast<unsigned short>(7), static_cast<signed long>(4)), ""); |
| |
| // Check the diagnostic message |
| _Alignas(void) char align_void_array[1]; // both-error {{invalid application of '_Alignas' to an incomplete type 'void'}} |
