79 lines
3.3 KiB
C
79 lines
3.3 KiB
C
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/*============================================================================
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This C source file is part of the SoftFloat IEEE Floating-Point Arithmetic
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Package, Release 3e, by John R. Hauser.
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Copyright 2011, 2012, 2013, 2014, 2015, 2016, 2017 The Regents of the
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University of California. All rights reserved.
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Redistribution and use in source and binary forms, with or without
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modification, are permitted provided that the following conditions are met:
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1. Redistributions of source code must retain the above copyright notice,
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this list of conditions, and the following disclaimer.
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2. Redistributions in binary form must reproduce the above copyright notice,
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this list of conditions, and the following disclaimer in the documentation
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and/or other materials provided with the distribution.
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3. Neither the name of the University nor the names of its contributors may
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be used to endorse or promote products derived from this software without
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specific prior written permission.
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THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS "AS IS", AND ANY
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EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
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WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ARE
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DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
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DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
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(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
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ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
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SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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=============================================================================*/
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#include <stdbool.h>
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#include <stdint.h>
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#include "internals.h"
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#include "primitives.h"
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#include "specialize.h"
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#include "softfloat.h"
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int64_t f64_to_i64(float64 a, uint8_t roundingMode, bool exact, struct softfloat_status_t *status)
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{
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bool sign;
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int16_t exp;
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uint64_t sig;
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int16_t shiftDist;
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struct uint64_extra sigExtra;
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/*------------------------------------------------------------------------
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*------------------------------------------------------------------------*/
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sign = signF64UI(a);
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exp = expF64UI(a);
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sig = fracF64UI(a);
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/*------------------------------------------------------------------------
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*------------------------------------------------------------------------*/
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if (exp) sig |= UINT64_C(0x0010000000000000);
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else if (softfloat_denormalsAreZeros(status)) sig = 0;
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shiftDist = 0x433 - exp;
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if (shiftDist <= 0) {
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if (shiftDist < -11) goto invalid;
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sigExtra.v = sig<<-shiftDist;
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sigExtra.extra = 0;
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} else {
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sigExtra = softfloat_shiftRightJam64Extra(sig, 0, shiftDist);
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}
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return softfloat_roundToI64(sign, sigExtra.v, sigExtra.extra, roundingMode, exact, status);
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/*------------------------------------------------------------------------
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*------------------------------------------------------------------------*/
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invalid:
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softfloat_raiseFlags(status, softfloat_flag_invalid);
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return (exp == 0x7FF) && fracF64UI(a)
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? i64_fromNaN
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: sign ? i64_fromNegOverflow : i64_fromPosOverflow;
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}
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