diff options
Diffstat (limited to 'softfloat/s_countLeadingZeros64.c')
| -rw-r--r--[-rwxr-xr-x] | softfloat/s_countLeadingZeros64.c | 59 |
1 files changed, 49 insertions, 10 deletions
diff --git a/softfloat/s_countLeadingZeros64.c b/softfloat/s_countLeadingZeros64.c index dbaff4f..34745b1 100755..100644 --- a/softfloat/s_countLeadingZeros64.c +++ b/softfloat/s_countLeadingZeros64.c @@ -1,20 +1,57 @@ -// See LICENSE.SoftFloat for license details. +/*============================================================================ + +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 <stdint.h> -#include "primitives.h" #include "platform.h" -int softfloat_countLeadingZeros64( uint64_t a ) +#ifndef softfloat_countLeadingZeros64 + +#define softfloat_countLeadingZeros64 softfloat_countLeadingZeros64 +#include "primitives.h" + +uint_fast8_t softfloat_countLeadingZeros64( uint64_t a ) { - int count; + uint_fast8_t count; uint32_t a32; - count = 32; - a32 = a; - if ( UINT64_C( 0x100000000 ) <= a ) { - count = 0; - a32 = a>>32; + count = 0; + a32 = a>>32; + if ( ! a32 ) { + count = 32; + a32 = a; } /*------------------------------------------------------------------------ | From here, result is current count + count leading zeros of `a32'. @@ -27,8 +64,10 @@ int softfloat_countLeadingZeros64( uint64_t a ) count += 8; a32 <<= 8; } - count += softfloat_countLeadingZeros8[ a32>>24 ]; + count += softfloat_countLeadingZeros8[a32>>24]; return count; } +#endif + |