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			104 lines
		
	
	
		
			4.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			104 lines
		
	
	
		
			4.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| 
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| /*============================================================================
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| =============================================================================*/
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| 
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| #include <stdbool.h>
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| #include <stdint.h>
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| #include "platform.h"
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| #include "internals.h"
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| #include "specialize.h"
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| #include "softfloat.h"
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| 
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| uint_fast64_t f64_to_ui64( float64_t a, uint_fast8_t roundingMode, bool exact )
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| {
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|     union ui64_f64 uA;
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|     uint_fast64_t uiA;
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|     bool sign;
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|     int_fast16_t exp;
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|     uint_fast64_t sig;
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|     int_fast16_t shiftDist;
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| #ifdef SOFTFLOAT_FAST_INT64
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|     struct uint64_extra sigExtra;
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| #else
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|     uint32_t extSig[3];
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| #endif
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| 
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|     /*------------------------------------------------------------------------
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|     *------------------------------------------------------------------------*/
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|     uA.f = a;
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|     uiA = uA.ui;
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|     sign = signF64UI( uiA );
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|     exp  = expF64UI( uiA );
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|     sig  = fracF64UI( uiA );
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|     /*------------------------------------------------------------------------
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|     *------------------------------------------------------------------------*/
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|     if ( exp ) sig |= UINT64_C( 0x0010000000000000 );
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|     shiftDist = 0x433 - exp;
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| #ifdef SOFTFLOAT_FAST_INT64
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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
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|         softfloat_roundToUI64(
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|             sign, sigExtra.v, sigExtra.extra, roundingMode, exact );
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| #else
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|     extSig[indexWord( 3, 0 )] = 0;
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|     if ( shiftDist <= 0 ) {
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|         if ( shiftDist < -11 ) goto invalid;
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|         sig <<= -shiftDist;
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|         extSig[indexWord( 3, 2 )] = sig>>32;
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|         extSig[indexWord( 3, 1 )] = sig;
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|     } else {
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|         extSig[indexWord( 3, 2 )] = sig>>32;
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|         extSig[indexWord( 3, 1 )] = sig;
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|         softfloat_shiftRightJam96M( extSig, shiftDist, extSig );
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|     }
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|     return softfloat_roundMToUI64( sign, extSig, roundingMode, exact );
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| #endif
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|     /*------------------------------------------------------------------------
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|     *------------------------------------------------------------------------*/
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|  invalid:
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|     softfloat_raiseFlags( softfloat_flag_invalid );
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|     return
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|         (exp == 0x7FF) && fracF64UI( uiA ) ? ui64_fromNaN
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|             : sign ? ui64_fromNegOverflow : ui64_fromPosOverflow;
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| 
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| }
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| 
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