57b08b0944
to reflect the new license. These used slightly different spellings that defeated my regular expressions. We understand that people may be surprised that we're moving the header entirely to discuss the new license. We checked this carefully with the Foundation's lawyer and we believe this is the correct approach. Essentially, all code in the project is now made available by the LLVM project under our new license, so you will see that the license headers include that license only. Some of our contributors have contributed code under our old license, and accordingly, we have retained a copy of our old license notice in the top-level files in each project and repository. llvm-svn: 351648
50 lines
1.6 KiB
C
50 lines
1.6 KiB
C
//===-- lib/floatditf.c - integer -> quad-precision conversion ----*- C -*-===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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// This file implements di_int to quad-precision conversion for the
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// compiler-rt library in the IEEE-754 default round-to-nearest, ties-to-even
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// mode.
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//
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//===----------------------------------------------------------------------===//
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#define QUAD_PRECISION
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#include "fp_lib.h"
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#if defined(CRT_HAS_128BIT) && defined(CRT_LDBL_128BIT)
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COMPILER_RT_ABI fp_t __floatditf(di_int a) {
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const int aWidth = sizeof a * CHAR_BIT;
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// Handle zero as a special case to protect clz
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if (a == 0)
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return fromRep(0);
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// All other cases begin by extracting the sign and absolute value of a
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rep_t sign = 0;
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du_int aAbs = (du_int)a;
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if (a < 0) {
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sign = signBit;
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aAbs = ~(du_int)a + 1U;
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}
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// Exponent of (fp_t)a is the width of abs(a).
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const int exponent = (aWidth - 1) - __builtin_clzll(aAbs);
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rep_t result;
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// Shift a into the significand field, rounding if it is a right-shift
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const int shift = significandBits - exponent;
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result = (rep_t)aAbs << shift ^ implicitBit;
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// Insert the exponent
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result += (rep_t)(exponent + exponentBias) << significandBits;
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// Insert the sign bit and return
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return fromRep(result | sign);
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}
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#endif
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