?? ref_norm.c
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/* ____________________________________________________________________
*
* Copyright (c) 2003, Andrew N. Sloss, Dominic Symes, Chris Wright
* All rights reserved.
* ____________________________________________________________________
*
* NON-COMMERCIAL USE License
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. For NON-COMMERCIAL USE only.
*
* 2. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 3. 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.
*
* 4. All advertising materials mentioning features or use of this
* software must display the following acknowledgement:
*
* This product includes software developed by Andrew N. Sloss,
* Chris Wright and Dominic Symes.
*
* THIS SOFTWARE IS PROVIDED BY THE 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 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.
*
* If you have questions about this license or would like a different
* license please email : andrew@sloss.net
*
* Reference code for examples of section 7.2
*/
#include "ch07test.h"
__value_in_regs pair32 ref_unorm(int32 a)
{
pair32 r;
uint32 x, shift;
x=a;
if (x==0)
{
shift=32;
}
else
{
shift=0;
while (x<0x80000000ul)
{
x<<=1;
shift++;
}
}
r.a = x;
r.b = shift;
return r;
}
__value_in_regs pair32 ref_snorm(int32 a)
{
pair32 r;
sint32 x, shift;
x=a;
if (x==0)
{
shift=32;
}
else
{
shift=0;
while (-(1<<30)<=x && x<(1<<30))
{
x<<=1;
shift++;
}
}
r.a = x;
r.b = shift;
return r;
}
/* count trailing zeros */
int32 ref_ctz(int32 a)
{
uint32 x = a;
int shift=0;
while ((x&1)==0)
{
x = (x>>1) | (1u<<31);
shift++;
}
return shift;
}
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