/*
===========================================================================
File: ENH1632.C v.2.3 - 30.Nov.2009
===========================================================================
ITU-T STL BASIC OPERATORS
ENHANCED 16-BIT & 32-BIT ARITHMETIC OPERATORS
History:
07 Nov 04 v2.0 Incorporation of new 32-bit / 40-bit / control
operators for the ITU-T Standard Tool Library as
described in Geneva, 20-30 January 2004 WP 3/16 Q10/16
TD 11 document and subsequent discussions on the
wp3audio@yahoogroups.com email reflector.
============================================================================
*/
/*****************************************************************************
*
* Enhanced 16/32 bit operators :
* s_max()
* s_min()
* L_max()
* L_min()
* shl_r()
* L_shl_r()
* L_mac0()
* L_mult0()
* L_msu0()
* s_and()
* s_or()
* s_xor()
* L_and()
* L_or()
* lshl()
* lshr()
* L_lshl()
* L_lshr()
* rotr()
* rotl()
* L_rotr()
* L_rotl()
*
*****************************************************************************/
/*****************************************************************************
*
* Include-Files
*
*****************************************************************************/
#include <stdio.h>
#include <stdlib.h>
#include "stl.h"
/*****************************************************************************
*
* Constants and Globals
*
*****************************************************************************/
/*****************************************************************************
*
* Functions
*
*****************************************************************************/
/*****************************************************************************
*
* Function Name : lshl
*
* Purpose :
*
* Logically shifts left var1 by var2 positions.
* - If var2 is negative, var1 is shifted to the LSBits by (-var2)
* positions with insertion of 0 at the MSBit.
* - If var2 is positive, var1 is shifted to the MSBits by (var2)
* positions.
*
* Complexity weight : 1
*
* Inputs :
*
* var1 16 bit short signed integer (Word16) whose value falls in
* the range 0xffff 8000 <= var1 <= 0x0000 7fff.
*
* var2 16 bit short signed integer (Word16) whose value falls in
* the range 0xffff 8000 <= var2 <= 0x0000 7fff.
*
* Outputs :
*
* none
*
* Return Value:
*
* var_out 16 bit short signed integer (Word16) whose value falls in
* the range 0xffff 8000 <= var_out <= 0x0000 7fff.
*
*****************************************************************************/
Word16 lshl( Word16 var1, Word16 var2)
{
Word16 var_out=0;
if( var2 < 0)
{
var2 = -var2;
var_out = lshr( var1, var2);
}
else
{
if( var2 == 0 || var1 == 0)
{
var_out = var1;
}
else if( var2 >= 16)
{
var_out = 0;
}
else
{
var_out = var1 << var2;
}
}
BASOP_CHECK();
return( var_out);
}
/*****************************************************************************
*
* Function Name : lshr
*
* Purpose :
*
* Logically shifts right var1 by var2 positions.
* - If var2 is positive, var1 is shifted to the LSBits by (var2)
* positions with insertion of 0 at the MSBit.
* - If var2 is negative, var1 is shifted to the MSBits by (-var2)
* positions.
*
* Complexity weight : 1
*
* Inputs :
*
* var1 16 bit short signed integer (Word16) whose value falls in
* the range 0xffff 8000 <= var1 <= 0x0000 7fff.
*
* var2 16 bit short signed integer (Word16) whose value falls in
* the range 0xffff 8000 <= var2 <= 0x0000 7fff.
*
* Outputs :
*
* none
*
* Return Value:
*
* var_out 16 bit short signed integer (Word16) whose value falls in
* the range 0xffff 8000 <= var_out <= 0x0000 7fff.
*
*****************************************************************************/
Word16 lshr( Word16 var1, Word16 var2)
{
Word16 var_out;
if( var2 < 0)
{
var2 = -var2;
var_out = lshl( var1, var2);
}
else
{
if( var2 == 0 || var1 == 0)
{
var_out = var1;
}
else if( var2 >= 16)
{
var_out = 0;
}
else
{
var_out = var1 >> 1;
var_out = var_out & 0x7fff;
var_out = var_out >> ( var2-1);
}
}
BASOP_CHECK();
return( var_out);
}
/*****************************************************************************
*
* Function Name : L_lshl
*
* Purpose :
*
* Logically shifts left L_var1 by var2 positions.
* - If var2 is negative, L_var1 is shifted to the LSBits by (-var2)
* positions with insertion of 0 at the MSBit.
* - If var2 is positive, L_var1 is shifted to the MSBits by (var2)
* positions.
*
* Complexity weight : 1
*
* Inputs :
*
* L_var1 32 bit long signed integer (Word32) whose value falls in
* the range 0x8000 0000 <= L_var1 <= 0x7fff ffff.
*
* var2 16 bit short signed integer (Word16) whose value falls in
* the range 0xffff 8000 <= var2 <= 0x0000 7fff.
*
* Outputs :
*
* none
*
* Return Value:
*
* L_var_out 32 bit long signed integer (Word32) whose value falls in
* the range 0x8000 0000 <= L_var_out <= 0x7fff ffff.
*
*****************************************************************************/
Word32 L_lshl( Word32 L_var1, Word16 var2)
{
Word32 L_var_out=0;
if( var2 < 0)
{
var2 = -var2;
L_var_out = L_lshr( L_var1, var2);
}
else
{
if( var2 == 0 || L_var1 == 0)
{
L_var_out = L_var1;
}
else if( var2 >= 32)
{
L_var_out = 0;
}
else
{
L_var_out = L_var1 << var2;
}
}
BASOP_CHECK();
return( L_var_out);
}
/*****************************************************************************
*
* Function Name : L_lshr
*
* Purpose :
*
* Logically shifts right L_var1 by var2 positions.
* - If var2 is positive, L_var1 is shifted to the LSBits by (var2)
* positions with insertion of 0 at the MSBit.
* - If var2 is negative, L_var1 is shifted to the MSBits by (-var2)
* positions.
*
* Complexity weight : 1
*
* Inputs :
*
* L_var1 32 bit long signed integer (Word32) whose value falls in
* the range 0x8000 0000 <= L_var1 <= 0x7fff ffff.
*
* var2 16 bit short signed integer (Word16) whose value falls in
* the range 0xffff 8000 <= var2 <= 0x0000 7fff.
*
* Outputs :
*
* none
*
* Return Value:
*
* L_var_out 32 bit long signed integer (Word32) whose value falls in
* the range 0x8000 0000 <= L_var_out <= 0x7fff ffff.
*
*****************************************************************************/
Word32 L_lshr( Word32 L_var1, Word16 var2)
{
Word32 L_var_out;
if( var2 < 0)
{
var2 = -var2;
L_var_out = L_lshl( L_var1, var2);
}
else
{
if( var2 == 0 || L_var1 == 0)
{
L_var_out = L_var1;
}
else if( var2 >= 32)
{
L_var_out = 0;
}
else
{
L_var_out = L_var1 >> 1;
L_var_out = L_var_out & 0x7fffffff;
L_var_out = L_var_out >> (var2 - 1);
}
}
BASOP_CHECK();
return( L_var_out);
}
/*****************************************************************************
*
* Function Name : shl_r
*
* Purpose :
*
* Identical to shl( var1, var2) but with rounding. Saturates the result
* in case of underflows or overflows.
*
* Complexity weight : 3
*
* Inputs :
*
* var1 16 bit short signed integer (Word16) whose value falls in
* the range : 0xffff 8000 <= var1 <= 0x0000 7fff.
*
* var2 16 bit short signed integer (Word16) whose value falls in
* the range : 0xffff 8000 <= var2 <= 0x0000 7fff.
*
* Outputs :
*
* none
*
* Return Value :
*
* var_out 16 bit short signed integer (Word16) whose value falls in
* the range : 0xffff 8000 <= var_out <= 0x0000 7fff.
*
*****************************************************************************/
Word16 shl_r( Word16 var1, Word16 var2)
{
Word16 var_out;
if( var2 >= 0)
{
var_out = shl( var1, var2);
}
else
{
var2 = -var2;
var_out = shr_r( var1, var2);
}
return( var_out);
}
/*****************************************************************************
*
* Function Name : L_shl_r
*
* Purpose :
*
* Same as L_shl( var1, var2) but with rounding. Saturates the result in
* case of underflows or overflows.
*
* Complexity weight : 3
*
* Inputs :
*
* L_var1 32 bit long signed integer (Word32) whose value falls in
* the range : 0x8000 0000 <= L_var1 <= 0x7fff ffff.
*
* var2 16 bit short signed integer (Word16) whose value falls in
* the range : 0xffff 8000 <= var2 <= 0x0000 7fff.
*
* Outputs :
*
* none
*
* Return Value :
*
* L_var_out 32 bit long signed integer (Word32) whose value falls in
* the range : 0x8000 0000 <= var_out <= 0x7fff ffff.
*
*****************************************************************************/
Word32 L_shl_r( Word32 L_var1, Word16 var2)
{
Word32 var_out;
if( var2 >= 0)
{
var_out = L_shl( L_var1, var2);
}
else
{
var2 = -var2;
var_out = L_shr_r( L_var1, var2);
}
return( var_out);
}
/*****************************************************************************
*
* Function Name : rotr
*
* Purpose :
*
* Performs a 16-bit logical rotation of var1 by 1 bit to the LSBits. The
* MSBit is set to var2 bit 0. The LSBit of var1 is kept in *var3 bit 0.
*
* Complexity weight : 3
*
* Inputs :
*
* var1 16 bit short signed integer (Word16) whose value falls in
* the range : 0xffff 8000 <= var1 <= 0x0000 7fff.
*
* var2 16 bit short signed integer (Word16) whose value must be 0
* or 1.
*
* Outputs :
*
* *var3 Points on a 16 bit short signed integer (Word16) whose
* value will be 0 or 1.
*
* Return Value :
*
* var_out 16 bit short signed integer (Word16) whose value falls in
* the range : 0xffff 8000 <= var_out <= 0x0000 7fff.
*
*****************************************************************************/
Word16 rotr( Word16 var1, Word16 var2, Word16 *var3)
{
Word16 var_out;
*var3 = s_and( var1, 0x1);
var_out = s_or( lshr( var1, 1),
lshl( var2, 15));
return( var_out);
}
/*****************************************************************************
*
* Function Name : rotl
*
* Purpose :
*
* Performs a 16-bit logical rotation of var1 by 1 bit to the MSBits. The
* LSBit is set to var2 bit 0. The MSBit of var1 is kept in *var3 bit 0.
*
* Complexity weight : 3
*
* Inputs :
*
* var1 16 bit short signed integer (Word16) whose value falls in
* the range : 0xffff 8000 <= var1 <= 0x0000 7fff.
*
* var2 16 bit short signed integer (Word16) whose value must be 0
* or 1.
*
* Outputs :
*
* *var3 Points on a 16 bit short signed integer (Word16) whose
* value will be 0 or 1.
*
* Return Value :
*
* var_out 16 bit short signed integer (Word16) whose value falls in
* the range : 0xffff 8000 <= var_out <= 0x0000 7fff.
*
*****************************************************************************/
Word16 rotl( Word16 var1, Word16 var2, Word16 *var3)
{
Word16 var_out;
*var3 = lshr( var1, 15);
var_out = s_or( lshl( var1, 1),
s_and( var2, 0x1));
return( var_out);
}
/*****************************************************************************
*
* Function Name : L_rotr
*
* Purpose :
*
* Performs a 32-bit logical rotation of L_var1 by 1 bit to the LSBits. The
* MSBit is set to var2 bit 0. The LSBit of L_var1 is kept in *var3 bit 0.
*
* Complexity weight : 3
*
* Inputs :
*
* L_var1 32 bit long signed integer (Word32) whose value falls in
* the range : 0x8000 0000 <= L_var1 <= 0x7fff ffff.
*
* var2 16 bit short signed integer (Word16) whose value must be 0
* or 1.
*
* Outputs :
*
* *var3 Points on a 16 bit short signed integer (Word16) whose
* value will be 0 or 1.
*
* Return Value :
*
* L_var_out 32 bit long signed integer (Word32) whose value falls in
* the range : 0x8000 0000 <= L_var_out <= 0x7fff ffff.
*
*****************************************************************************/
Word32 L_rotr( Word32 L_var1, Word16 var2, Word16 *var3)
{
Word32 L_var_out;
*var3 = s_and( extract_l( L_var1), 0x1);
L_var_out = L_or( L_lshr( L_var1, 1),
L_lshl( L_deposit_l( var2), 31));
return( L_var_out);
}
/*****************************************************************************
*
* Function Name : L_rotl
*
* Purpose :
*
* Performs a 32-bit logical rotation of L_var1 by 1 bit to the MSBits. The
* LSBit is set to var2 bit 0. The MSBit of L_var1 is kept in *var3 bit 0.
*
* Complexity weight : 3
*
* Inputs :
*
* L_var1 32 bit long signed integer (Word32) whose value falls in
* the range : 0x8000 0000 <= L_var1 <= 0x7fff ffff.
*
* var2 16 bit short signed integer (Word16) whose value must be 0
* or 1.
*
* Outputs :
*
* *var3 Points on a 16 bit short signed integer (Word16) whose
* value will be 0 or 1.
*
* Return Value :
*
* L_var_out 32 bit long signed integer (Word32) whose value falls in
* the range : 0x8000 0000 <= L_var_out <= 0x7fff ffff.
*
*****************************************************************************/
Word32 L_rotl( Word32 L_var1, Word16 var2, Word16 *var3)
{
Word32 L_var_out;
*var3 = extract_l( L_lshr( L_var1, 31));
L_var_out = L_or( L_lshl( L_var1, 1),
L_deposit_l( s_and( var2, 0x1)));
return( L_var_out);
}
/* end of file */