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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 unsigned integer conversion for the10// compiler-rt library.11//12//===----------------------------------------------------------------------===//13 14#include "fp_lib.h"15 16static __inline fixuint_t __fixuint(fp_t a) {17 // Break a into sign, exponent, significand parts.18 const rep_t aRep = toRep(a);19 const rep_t aAbs = aRep & absMask;20 const int sign = aRep & signBit ? -1 : 1;21 const int exponent = (aAbs >> significandBits) - exponentBias;22 const rep_t significand = (aAbs & significandMask) | implicitBit;23 24 // If either the value or the exponent is negative, the result is zero.25 if (sign == -1 || exponent < 0)26 return 0;27 28 // If the value is too large for the integer type, saturate.29 if ((unsigned)exponent >= sizeof(fixuint_t) * CHAR_BIT)30 return ~(fixuint_t)0;31 32 // If 0 <= exponent < significandBits, right shift to get the result.33 // Otherwise, shift left.34 if (exponent < significandBits)35 return significand >> (significandBits - exponent);36 else37 return (fixuint_t)significand << (exponent - significandBits);38}39