13cab2bb3Spatrick //===-- lib/floatunsitf.c - uint -> quad-precision conversion -----*- C -*-===// 23cab2bb3Spatrick // 33cab2bb3Spatrick // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 43cab2bb3Spatrick // See https://llvm.org/LICENSE.txt for license information. 53cab2bb3Spatrick // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 63cab2bb3Spatrick // 73cab2bb3Spatrick //===----------------------------------------------------------------------===// 83cab2bb3Spatrick // 93cab2bb3Spatrick // This file implements unsigned integer to quad-precision conversion for the 103cab2bb3Spatrick // compiler-rt library in the IEEE-754 default round-to-nearest, ties-to-even 113cab2bb3Spatrick // mode. 123cab2bb3Spatrick // 133cab2bb3Spatrick //===----------------------------------------------------------------------===// 143cab2bb3Spatrick 153cab2bb3Spatrick #define QUAD_PRECISION 163cab2bb3Spatrick #include "fp_lib.h" 173cab2bb3Spatrick 183cab2bb3Spatrick #if defined(CRT_HAS_128BIT) && defined(CRT_LDBL_128BIT) __floatunsitf(su_int a)19*810390e3SrobertCOMPILER_RT_ABI fp_t __floatunsitf(su_int a) { 203cab2bb3Spatrick 213cab2bb3Spatrick const int aWidth = sizeof a * CHAR_BIT; 223cab2bb3Spatrick 233cab2bb3Spatrick // Handle zero as a special case to protect clz 243cab2bb3Spatrick if (a == 0) 253cab2bb3Spatrick return fromRep(0); 263cab2bb3Spatrick 273cab2bb3Spatrick // Exponent of (fp_t)a is the width of abs(a). 28*810390e3Srobert const int exponent = (aWidth - 1) - clzsi(a); 293cab2bb3Spatrick rep_t result; 303cab2bb3Spatrick 313cab2bb3Spatrick // Shift a into the significand field and clear the implicit bit. 323cab2bb3Spatrick const int shift = significandBits - exponent; 333cab2bb3Spatrick result = (rep_t)a << shift ^ implicitBit; 343cab2bb3Spatrick 353cab2bb3Spatrick // Insert the exponent 363cab2bb3Spatrick result += (rep_t)(exponent + exponentBias) << significandBits; 373cab2bb3Spatrick return fromRep(result); 383cab2bb3Spatrick } 393cab2bb3Spatrick 403cab2bb3Spatrick #endif 41