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1//===-- lib/fixdfsi.c - Double-precision -> integer conversion ----*- C -*-===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8//9// This file implements float to integer conversion for the10// compiler-rt library.11//12//===----------------------------------------------------------------------===//13 14#include "fp_lib.h"15 16static __inline fixint_t __fixint(fp_t a) {17 const fixint_t fixint_max = (fixint_t)((~(fixuint_t)0) / 2);18 const fixint_t fixint_min = -fixint_max - 1;19 // Break a into sign, exponent, significand parts.20 const rep_t aRep = toRep(a);21 const rep_t aAbs = aRep & absMask;22 const fixint_t sign = aRep & signBit ? -1 : 1;23 const int exponent = (aAbs >> significandBits) - exponentBias;24 const rep_t significand = (aAbs & significandMask) | implicitBit;25 26 // If exponent is negative, the result is zero.27 if (exponent < 0)28 return 0;29 30 // If the value is too large for the integer type, saturate.31 if ((unsigned)exponent >= sizeof(fixint_t) * CHAR_BIT)32 return sign == 1 ? fixint_max : fixint_min;33 34 // If 0 <= exponent < significandBits, right shift to get the result.35 // Otherwise, shift left.36 if (exponent < significandBits)37 return (fixint_t)(sign * (significand >> (significandBits - exponent)));38 else39 return (fixint_t)(sign * ((fixuint_t)significand << (exponent - significandBits)));40}41