41 lines · c
1//===-- lib/floatunsitf.c - uint -> quad-precision 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 unsigned integer to quad-precision conversion for the10// compiler-rt library in the IEEE-754 default round-to-nearest, ties-to-even11// mode.12//13//===----------------------------------------------------------------------===//14 15#define QUAD_PRECISION16#include "fp_lib.h"17 18#if defined(CRT_HAS_TF_MODE)19COMPILER_RT_ABI fp_t __floatunsitf(su_int a) {20 21 const int aWidth = sizeof a * CHAR_BIT;22 23 // Handle zero as a special case to protect clz24 if (a == 0)25 return fromRep(0);26 27 // Exponent of (fp_t)a is the width of abs(a).28 const int exponent = (aWidth - 1) - clzsi(a);29 rep_t result;30 31 // Shift a into the significand field and clear the implicit bit.32 const int shift = significandBits - exponent;33 result = (rep_t)a << shift ^ implicitBit;34 35 // Insert the exponent36 result += (rep_t)(exponent + exponentBias) << significandBits;37 return fromRep(result);38}39 40#endif41