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/*
* Copyright 2024 WebAssembly Community Group participants
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef wasm_stdckdint_h
#define wasm_stdckdint_h
// This is a partial "polyfill" for the C23 file stdckdint.h. It allows us to
// use that API even in older compilers.
namespace std {
template<typename T> bool ckd_add(T* output, T a, T b) {
#if __has_builtin(__builtin_add_overflow)
return __builtin_add_overflow(a, b, output);
#else
// Atm this polyfill only supports unsigned types.
static_assert(std::is_unsigned_v<T>);
T result = a + b;
if (result < a) {
return true;
}
*output = result;
return false;
#endif
}
} // namespace std
#endif // wasm_stdckdint_h