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/* { dg-additional-options "-std=c++20" } */
/* bit_cast and memcpy */
#include <bit>
#include <cstring>
#include "target-flex-common.h"
struct S0
{
int _v0;
char _v1;
long long _v2;
};
struct S1
{
int _v0;
char _v1;
long long _v2;
};
bool test_bit_cast(int arg)
{
bool ok;
S1 s1_out;
#pragma omp target map(from: ok, s1_out) map(to: arg)
{
bool inner_ok = true;
{
long long v = static_cast<long long>(arg + 42ll);
S0 s = {arg, 'a', v};
VERIFY (std::bit_cast<S1>(s)._v0 == arg);
VERIFY (std::bit_cast<S1>(s)._v1 == 'a');
VERIFY (std::bit_cast<S1>(s)._v2 == v);
s1_out = std::bit_cast<S1>(s);
}
end:
ok = inner_ok;
}
if (!ok)
return false;
long long v = static_cast<long long>(arg + 42ll);
VERIFY_NON_TARGET (std::bit_cast<S0>(s1_out)._v0 == arg);
VERIFY_NON_TARGET (std::bit_cast<S0>(s1_out)._v1 == 'a');
VERIFY_NON_TARGET (std::bit_cast<S0>(s1_out)._v2 == v);
return true;
}
struct OutStruct
{
std::size_t _id;
void *_next;
};
struct Extendable1
{
std::size_t _id;
void *_next;
int _v;
};
struct Extendable2
{
std::size_t _id;
void *_next;
char _str[256];
};
struct Extendable3
{
std::size_t _id;
void *_next;
const int *_nums;
std::size_t _size;
};
struct ExtendableUnknown
{
std::size_t _id;
void *_next;
};
template<typename To, std::size_t Id>
To *get_extendable(void *p)
{
while (p != nullptr)
{
OutStruct out;
std::memcpy(&out, p, sizeof(OutStruct));
if (out._id == Id)
return static_cast<To *>(p);
p = out._next;
}
return nullptr;
}
bool test_memcpy(int arg, const int *nums, std::size_t nums_size)
{
bool ok;
Extendable2 e2_out;
#pragma omp target map(from: ok, e2_out) map(to: arg, nums[:nums_size], nums_size)
{
bool inner_ok = true;
{
Extendable3 e3 = {3u, nullptr, nums, nums_size};
ExtendableUnknown u1 = {100u, &e3};
Extendable2 e2 = {2u, &u1, {'H', 'e', 'l', 'l', 'o', '!', '\000'}};
ExtendableUnknown u2 = {101u, &e2};
ExtendableUnknown u3 = {102u, &u2};
ExtendableUnknown u4 = {142u, &u3};
Extendable1 e1 = {1u, &u4, arg};
void *p = &e1;
while (p != nullptr)
{
/* You can always cast a pointer to a struct to a pointer to
the type of it's first member. */
switch (*static_cast<std::size_t *>(p))
{
case 1:
{
Extendable1 *e1_p = static_cast<Extendable1 *>(p);
p = e1_p->_next;
VERIFY (e1_p->_v == arg);
break;
}
case 2:
{
Extendable2 *e2_p = static_cast<Extendable2 *>(p);
p = e2_p->_next;
VERIFY (std::strcmp(e2_p->_str, "Hello!") == 0);
break;
}
case 3:
{
Extendable3 *e3_p = static_cast<Extendable3 *>(p);
p = e3_p->_next;
VERIFY (nums == e3_p->_nums);
VERIFY (nums_size == e3_p->_size);
break;
}
default:
{
/* Casting to a pointer to OutStruct invokes undefined
behavior though, memcpy is required to extract the _next
member. */
OutStruct out;
std::memcpy(&out, p, sizeof(OutStruct));
p = out._next;
}
}
}
Extendable2 *e2_p = get_extendable<Extendable2, 2u>(&e1);
VERIFY (e2_p != nullptr);
e2_out = *e2_p;
}
end:
ok = inner_ok;
}
if (!ok)
return false;
VERIFY_NON_TARGET (e2_out._id == 2u);
VERIFY_NON_TARGET (std::strcmp(e2_out._str, "Hello!") == 0);
return true;
}
int main()
{
volatile int arg = 42;
int arr[8] = {0, 1, 2, 3, 4, 5, 6, 7};
return test_bit_cast(arg)
&& test_memcpy(arg, arr, 8) ? 0 : 1;
}
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