mirror of
				https://github.com/openhwgroup/cvw
				synced 2025-02-11 06:05:49 +00:00 
			
		
		
		
	
		
			
				
	
	
		
			151 lines
		
	
	
		
			5.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			151 lines
		
	
	
		
			5.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| 
 | |
| /*============================================================================
 | |
| 
 | |
| This C source file is part of the SoftFloat IEEE Floating-Point Arithmetic
 | |
| Package, Release 3e, by John R. Hauser.
 | |
| 
 | |
| Copyright 2011, 2012, 2013, 2014 The Regents of the University of California.
 | |
| All rights reserved.
 | |
| 
 | |
| Redistribution and use in source and binary forms, with or without
 | |
| modification, are permitted provided that the following conditions are met:
 | |
| 
 | |
|  1. Redistributions of source code must retain the above copyright notice,
 | |
|     this list of conditions, and the following disclaimer.
 | |
| 
 | |
|  2. Redistributions in binary form must reproduce the above copyright notice,
 | |
|     this list of conditions, and the following disclaimer in the documentation
 | |
|     and/or other materials provided with the distribution.
 | |
| 
 | |
|  3. Neither the name of the University nor the names of its contributors may
 | |
|     be used to endorse or promote products derived from this software without
 | |
|     specific prior written permission.
 | |
| 
 | |
| THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS "AS IS", AND ANY
 | |
| EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 | |
| WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ARE
 | |
| DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
 | |
| DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 | |
| (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 | |
| LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 | |
| ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 | |
| (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 | |
| SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 | |
| 
 | |
| =============================================================================*/
 | |
| 
 | |
| #include <stdbool.h>
 | |
| #include <stdint.h>
 | |
| #include "platform.h"
 | |
| #include "internals.h"
 | |
| #include "specialize.h"
 | |
| #include "softfloat.h"
 | |
| 
 | |
| float64_t f64_mul( float64_t a, float64_t b )
 | |
| {
 | |
|     union ui64_f64 uA;
 | |
|     uint_fast64_t uiA;
 | |
|     bool signA;
 | |
|     int_fast16_t expA;
 | |
|     uint_fast64_t sigA;
 | |
|     union ui64_f64 uB;
 | |
|     uint_fast64_t uiB;
 | |
|     bool signB;
 | |
|     int_fast16_t expB;
 | |
|     uint_fast64_t sigB;
 | |
|     bool signZ;
 | |
|     uint_fast64_t magBits;
 | |
|     struct exp16_sig64 normExpSig;
 | |
|     int_fast16_t expZ;
 | |
| #ifdef SOFTFLOAT_FAST_INT64
 | |
|     struct uint128 sig128Z;
 | |
| #else
 | |
|     uint32_t sig128Z[4];
 | |
| #endif
 | |
|     uint_fast64_t sigZ, uiZ;
 | |
|     union ui64_f64 uZ;
 | |
| 
 | |
|     /*------------------------------------------------------------------------
 | |
|     *------------------------------------------------------------------------*/
 | |
|     uA.f = a;
 | |
|     uiA = uA.ui;
 | |
|     signA = signF64UI( uiA );
 | |
|     expA  = expF64UI( uiA );
 | |
|     sigA  = fracF64UI( uiA );
 | |
|     uB.f = b;
 | |
|     uiB = uB.ui;
 | |
|     signB = signF64UI( uiB );
 | |
|     expB  = expF64UI( uiB );
 | |
|     sigB  = fracF64UI( uiB );
 | |
|     signZ = signA ^ signB;
 | |
|     /*------------------------------------------------------------------------
 | |
|     *------------------------------------------------------------------------*/
 | |
|     if ( expA == 0x7FF ) {
 | |
|         if ( sigA || ((expB == 0x7FF) && sigB) ) goto propagateNaN;
 | |
|         magBits = expB | sigB;
 | |
|         goto infArg;
 | |
|     }
 | |
|     if ( expB == 0x7FF ) {
 | |
|         if ( sigB ) goto propagateNaN;
 | |
|         magBits = expA | sigA;
 | |
|         goto infArg;
 | |
|     }
 | |
|     /*------------------------------------------------------------------------
 | |
|     *------------------------------------------------------------------------*/
 | |
|     if ( ! expA ) {
 | |
|         if ( ! sigA ) goto zero;
 | |
|         normExpSig = softfloat_normSubnormalF64Sig( sigA );
 | |
|         expA = normExpSig.exp;
 | |
|         sigA = normExpSig.sig;
 | |
|     }
 | |
|     if ( ! expB ) {
 | |
|         if ( ! sigB ) goto zero;
 | |
|         normExpSig = softfloat_normSubnormalF64Sig( sigB );
 | |
|         expB = normExpSig.exp;
 | |
|         sigB = normExpSig.sig;
 | |
|     }
 | |
|     /*------------------------------------------------------------------------
 | |
|     *------------------------------------------------------------------------*/
 | |
|     expZ = expA + expB - 0x3FF;
 | |
|     sigA = (sigA | UINT64_C( 0x0010000000000000 ))<<10;
 | |
|     sigB = (sigB | UINT64_C( 0x0010000000000000 ))<<11;
 | |
| #ifdef SOFTFLOAT_FAST_INT64
 | |
|     sig128Z = softfloat_mul64To128( sigA, sigB );
 | |
|     sigZ = sig128Z.v64 | (sig128Z.v0 != 0);
 | |
| #else
 | |
|     softfloat_mul64To128M( sigA, sigB, sig128Z );
 | |
|     sigZ =
 | |
|         (uint64_t) sig128Z[indexWord( 4, 3 )]<<32 | sig128Z[indexWord( 4, 2 )];
 | |
|     if ( sig128Z[indexWord( 4, 1 )] || sig128Z[indexWord( 4, 0 )] ) sigZ |= 1;
 | |
| #endif
 | |
|     if ( sigZ < UINT64_C( 0x4000000000000000 ) ) {
 | |
|         --expZ;
 | |
|         sigZ <<= 1;
 | |
|     }
 | |
|     return softfloat_roundPackToF64( signZ, expZ, sigZ );
 | |
|     /*------------------------------------------------------------------------
 | |
|     *------------------------------------------------------------------------*/
 | |
|  propagateNaN:
 | |
|     uiZ = softfloat_propagateNaNF64UI( uiA, uiB );
 | |
|     goto uiZ;
 | |
|     /*------------------------------------------------------------------------
 | |
|     *------------------------------------------------------------------------*/
 | |
|  infArg:
 | |
|     if ( ! magBits ) {
 | |
|         softfloat_raiseFlags( softfloat_flag_invalid );
 | |
|         uiZ = defaultNaNF64UI;
 | |
|     } else {
 | |
|         uiZ = packToF64UI( signZ, 0x7FF, 0 );
 | |
|     }
 | |
|     goto uiZ;
 | |
|     /*------------------------------------------------------------------------
 | |
|     *------------------------------------------------------------------------*/
 | |
|  zero:
 | |
|     uiZ = packToF64UI( signZ, 0, 0 );
 | |
|  uiZ:
 | |
|     uZ.ui = uiZ;
 | |
|     return uZ.f;
 | |
| 
 | |
| }
 | |
| 
 |