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+
+/*============================================================================
+
+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, 2015 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 extF80_to_f64( extFloat80_t a )
+{
+ union { struct extFloat80M s; extFloat80_t f; } uA;
+ uint_fast16_t uiA64;
+ uint_fast64_t uiA0;
+ bool sign;
+ int_fast32_t exp;
+ uint_fast64_t sig;
+ struct commonNaN commonNaN;
+ uint_fast64_t uiZ;
+ union ui64_f64 uZ;
+
+ /*------------------------------------------------------------------------
+ *------------------------------------------------------------------------*/
+ uA.f = a;
+ uiA64 = uA.s.signExp;
+ uiA0 = uA.s.signif;
+ sign = signExtF80UI64( uiA64 );
+ exp = expExtF80UI64( uiA64 );
+ sig = uiA0;
+ /*------------------------------------------------------------------------
+ *------------------------------------------------------------------------*/
+ if ( ! (exp | sig) ) {
+ uiZ = packToF64UI( sign, 0, 0 );
+ goto uiZ;
+ }
+ /*------------------------------------------------------------------------
+ *------------------------------------------------------------------------*/
+ if ( exp == 0x7FFF ) {
+ if ( sig & UINT64_C( 0x7FFFFFFFFFFFFFFF ) ) {
+ softfloat_extF80UIToCommonNaN( uiA64, uiA0, &commonNaN );
+ uiZ = softfloat_commonNaNToF64UI( &commonNaN );
+ } else {
+ uiZ = packToF64UI( sign, 0x7FF, 0 );
+ }
+ goto uiZ;
+ }
+ /*------------------------------------------------------------------------
+ *------------------------------------------------------------------------*/
+ sig = softfloat_shortShiftRightJam64( sig, 1 );
+ exp -= 0x3C01;
+ if ( sizeof (int_fast16_t) < sizeof (int_fast32_t) ) {
+ if ( exp < -0x1000 ) exp = -0x1000;
+ }
+ return softfloat_roundPackToF64( sign, exp, sig );
+ /*------------------------------------------------------------------------
+ *------------------------------------------------------------------------*/
+ uiZ:
+ uZ.ui = uiZ;
+ return uZ.f;
+
+}
+