// Copyright 2018 Ulf Adams // // The contents of this file may be used under the terms of the Apache License, // Version 2.0. // // (See accompanying file LICENSE-Apache or copy at // http://www.apache.org/licenses/LICENSE-2.0) // // Alternatively, the contents of this file may be used under the terms of // the Boost Software License, Version 1.0. // (See accompanying file LICENSE-Boost or copy at // https://www.boost.org/LICENSE_1_0.txt) // // Unless required by applicable law or agreed to in writing, this software // is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY // KIND, either express or implied. #include "ryu/common.h" int32_t __pow5bits(const int32_t e) { // This approximation works up to the point that the multiplication overflows at e = 3529. // If the multiplication were done in 64 bits, it would fail at 5^4004 which is just greater // than 2^9297. assert(e >= 0); assert(e <= 3528); return (int32_t) (((((uint32_t) e) * 1217359) >> 19) + 1); }