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76 lines
2.9 KiB
C
76 lines
2.9 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 3, by John R. Hauser.
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Copyright 2011, 2012, 2013, 2014 The Regents of the University of California
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(Regents). All Rights Reserved. Redistribution and use in source and binary
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forms, with or without modification, are permitted provided that the following
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conditions are met:
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Redistributions of source code must retain the above copyright notice,
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this list of conditions, and the following two paragraphs of disclaimer.
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Redistributions in binary form must reproduce the above copyright notice,
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this list of conditions, and the following two paragraphs of disclaimer in the
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documentation and/or other materials provided with the distribution. Neither
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the name of the Regents nor the names of its contributors may be used to
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endorse or promote products derived from this software without specific prior
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written permission.
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IN NO EVENT SHALL REGENTS BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT,
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SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING LOST PROFITS, ARISING
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OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF REGENTS HAS
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BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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REGENTS SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT LIMITED
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TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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PURPOSE. THE SOFTWARE AND ACCOMPANYING DOCUMENTATION, IF ANY, PROVIDED
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HEREUNDER IS PROVIDED "AS IS". REGENTS HAS NO OBLIGATION TO PROVIDE
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MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
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=============================================================================*/
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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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int
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softfloat_shiftNormSigF128M(
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const uint32_t *wPtr, uint_fast8_t shiftCount, uint32_t *sigPtr )
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{
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uint32_t wordSig;
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int32_t exp;
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uint32_t leadingBit;
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wordSig = wPtr[indexWordHi( 4 )];
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exp = expF128UI96( wordSig );
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if ( exp ) {
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softfloat_shortShiftLeft128M( wPtr, shiftCount, sigPtr );
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leadingBit = 0x00010000<<shiftCount;
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sigPtr[indexWordHi( 4 )] =
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(sigPtr[indexWordHi( 4 )] & (leadingBit - 1)) | leadingBit;
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} else {
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exp = 16;
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wordSig &= 0x7FFFFFFF;
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if ( ! wordSig ) {
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exp = -16;
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wordSig = wPtr[indexWord( 4, 2 )];
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if ( ! wordSig ) {
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exp = -48;
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wordSig = wPtr[indexWord( 4, 1 )];
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if ( ! wordSig ) {
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wordSig = wPtr[indexWord( 4, 0 )];
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if ( ! wordSig ) return -128;
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exp = -80;
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}
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}
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}
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exp -= softfloat_countLeadingZeros32( wordSig );
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softfloat_shiftLeft128M( wPtr, 1 - exp + shiftCount, sigPtr );
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}
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return exp;
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}
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