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1//===-- lib/floatunsisf.c - uint -> single-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 single-precision conversion for the10// compiler-rt library in the IEEE-754 default round-to-nearest, ties-to-even11// mode.12//13//===----------------------------------------------------------------------===//14 15#define SINGLE_PRECISION16#include "fp_lib.h"17 18#include "int_lib.h"19 20COMPILER_RT_ABI fp_t __floatunsisf(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, rounding if it is a right-shift33 if (exponent <= significandBits) {34 const int shift = significandBits - exponent;35 result = (rep_t)a << shift ^ implicitBit;36 } else {37 const int shift = exponent - significandBits;38 result = (rep_t)a >> shift ^ implicitBit;39 rep_t round = (rep_t)a << (typeWidth - shift);40 if (round > signBit)41 result++;42 if (round == signBit)43 result += result & 1;44 }45 46 // Insert the exponent47 result += (rep_t)(exponent + exponentBias) << significandBits;48 return fromRep(result);49}50 51#if defined(__ARM_EABI__)52#if defined(COMPILER_RT_ARMHF_TARGET)53AEABI_RTABI fp_t __aeabi_ui2f(unsigned int a) { return __floatunsisf(a); }54#else55COMPILER_RT_ALIAS(__floatunsisf, __aeabi_ui2f)56#endif57#endif58