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1//===-- lib/floatunsidf.c - uint -> double-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 double-precision conversion for the10// compiler-rt library in the IEEE-754 default round-to-nearest, ties-to-even11// mode.12//13//===----------------------------------------------------------------------===//14 15#define DOUBLE_PRECISION16#include "fp_lib.h"17 18#include "int_lib.h"19 20COMPILER_RT_ABI fp_t __floatunsidf(su_int a) {21 22 const int aWidth = sizeof a * CHAR_BIT;23 24 // Handle zero as a special case to protect clz25 if (a == 0)26 return fromRep(0);27 28 // Exponent of (fp_t)a is the width of abs(a).29 const int exponent = (aWidth - 1) - clzsi(a);30 rep_t result;31 32 // Shift a into the significand field and clear the implicit bit.33 const int shift = significandBits - exponent;34 result = (rep_t)a << shift ^ implicitBit;35 36 // Insert the exponent37 result += (rep_t)(exponent + exponentBias) << significandBits;38 return fromRep(result);39}40 41#if defined(__ARM_EABI__)42#if defined(COMPILER_RT_ARMHF_TARGET)43AEABI_RTABI fp_t __aeabi_ui2d(su_int a) { return __floatunsidf(a); }44#else45COMPILER_RT_ALIAS(__floatunsidf, __aeabi_ui2d)46#endif47#endif48