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frameworks/av/media/codecs/amrwb/enc/inc/basic_op.h

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android 13 from xiaosuan
2025-08-25 08:17:13 +08:00
/*
** Copyright 2003-2010, VisualOn, Inc.
**
** Licensed under the Apache License, Version 2.0 (the "License");
** you may not use this file except in compliance with the License.
** You may obtain a copy of the License at
**
** http://www.apache.org/licenses/LICENSE-2.0
**
** Unless required by applicable law or agreed to in writing, software
** distributed under the License is distributed on an "AS IS" BASIS,
** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
** See the License for the specific language governing permissions and
** limitations under the License.
*/
#ifndef __BASIC_OP_H__
#define __BASIC_OP_H__
#include <stdio.h>
#include <stdlib.h>
#include "typedef.h"
#define MAX_32 (Word32)0x7fffffffL
#define MIN_32 (Word32)0x80000000L
#define MAX_16 ((Word16)+32767) /* 0x7fff */
#define MIN_16 ((Word16)-32768) /* 0x8000 */
#define static_vo static __inline
#define saturate(L_var1) (((L_var1) > 0X00007fffL) ? (MAX_16): (((L_var1) < (Word32) 0xffff8000L) ? (MIN_16): ((L_var1) & 0xffff)))
#define abs_s(x) ((Word16)(((x) != MIN_16) ? (((x) >= 0) ? (x) : (-(x))) : MAX_16)) /* Short abs, 1 */
#define L_deposit_h(x) (((Word32)(x)) << 16) /* 16 bit var1 -> MSB, 2 */
#define L_deposit_l(x) ((Word32)(x)) /* 16 bit var1 -> LSB, 2 */
#define L_abs(x) (((x) != MIN_32) ? (((x) >= 0) ? (x) : (-(x))) : MAX_32) /* Long abs, 3*/
#define negate(var1) ((Word16)(((var1) == MIN_16) ? MAX_16 : (-(var1)))) /* Short negate, 1*/
#define L_negate(L_var1) (((L_var1) == (MIN_32)) ? (MAX_32) : (-(L_var1))) /* Long negate, 2*/
#define extract_h(a) ((Word16)((a) >> 16))
#define extract_l(x) (Word16)((x))
#define add1(a,b) ((a) + (b))
#define vo_L_msu(a,b,c) ((a) - (((b) * (c)) << 1))
#define vo_mult32(a, b) ((a) * (b))
#define vo_mult(a,b) (((a) * (b)) >> 15)
#define vo_L_mult(a,b) (((a) * (b)) << 1)
#define vo_shr_r(var1, var2) (((var1)+((Word16)(1L<<((var2)-1))))>>(var2))
#define vo_sub(a,b) ((a) - (b))
#define vo_L_deposit_h(a) ((Word32)((a) << 16))
#define vo_round(a) ((((a) >> 15) + 1) >> 1)
#define vo_extract_l(a) ((Word16)(a))
#define vo_L_add(a,b) ((a) + (b))
#define vo_L_sub(a,b) ((a) - (b))
#define vo_mult_r(a,b) (((( (a) * (b) ) >> 14) + 1 ) >> 1 )
#define vo_negate(a) (-(a))
#define vo_L_shr_r(L_var1, var2) (((L_var1)+((Word32)(1L<<((var2)-1))))>>(var2))
/*___________________________________________________________________________
| |
| Prototypes for basic arithmetic operators |
|___________________________________________________________________________|
*/
static_vo Word16 add (Word16 var1, Word16 var2); /* Short add,1 */
static_vo Word16 sub (Word16 var1, Word16 var2); /* Short sub,1 */
static_vo Word16 shl (Word16 var1, Word16 var2); /* Short shift left, 1 */
static_vo Word16 shr (Word16 var1, Word16 var2); /* Short shift right, 1 */
static_vo Word16 mult (Word16 var1, Word16 var2); /* Short mult, 1 */
static_vo Word32 L_mult (Word16 var1, Word16 var2); /* Long mult, 1 */
static_vo Word16 voround (Word32 L_var1); /* Round, 1 */
static_vo Word32 L_mac (Word32 L_var3, Word16 var1, Word16 var2); /* Mac, 1 */
static_vo Word32 L_msu (Word32 L_var3, Word16 var1, Word16 var2); /* Msu, 1 */
static_vo Word32 L_add (Word32 L_var1, Word32 L_var2); /* Long add, 2 */
static_vo Word32 L_sub (Word32 L_var1, Word32 L_var2); /* Long sub, 2 */
static_vo Word16 mult_r (Word16 var1, Word16 var2); /* Mult with round, 2 */
static_vo Word32 L_shl2(Word32 L_var1, Word16 var2); /* var2 > 0*/
static_vo Word32 L_shl (Word32 L_var1, Word16 var2); /* Long shift left, 2 */
static_vo Word32 L_shr (Word32 L_var1, Word16 var2); /* Long shift right, 2*/
static_vo Word32 L_shr_r (Word32 L_var1, Word16 var2); /* Long shift right with round, 3 */
static_vo Word16 norm_s (Word16 var1); /* Short norm, 15 */
static_vo Word16 div_s (Word16 var1, Word16 var2); /* Short division, 18 */
static_vo Word16 norm_l (Word32 L_var1); /* Long norm, 30 */
/*___________________________________________________________________________
| |
| Functions |
|___________________________________________________________________________|
*/
/*___________________________________________________________________________
| |
| Function Name : add |
| |
| Purpose : |
| |
| Performs the addition (var1+var2) with overflow control and saturation;|
| the 16 bit result is set at +32767 when overflow occurs or at -32768 |
| when underflow occurs. |
| |
| 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 <= var1 <= 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. |
|___________________________________________________________________________|
*/
static_vo Word16 add (Word16 var1, Word16 var2)
{
Word16 var_out;
Word32 L_sum;
L_sum = (Word32) var1 + var2;
var_out = saturate (L_sum);
return (var_out);
}
/*___________________________________________________________________________
| |
| Function Name : sub |
| |
| Purpose : |
| |
| Performs the subtraction (var1+var2) with overflow control and satu- |
| ration; the 16 bit result is set at +32767 when overflow occurs or at |
| -32768 when underflow occurs. |
| |
| 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 <= var1 <= 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. |
|___________________________________________________________________________|
*/
static_vo Word16 sub (Word16 var1, Word16 var2)
{
Word16 var_out;
Word32 L_diff;
L_diff = (Word32) var1 - var2;
var_out = saturate (L_diff);
return (var_out);
}
/*___________________________________________________________________________
| |
| Function Name : shl |
| |
| Purpose : |
| |
| Arithmetically shift the 16 bit input var1 left var2 positions.Zero fill|
| the var2 LSB of the result. If var2 is negative, arithmetically shift |
| var1 right by -var2 with sign extension. Saturate the result in case of |
| underflows or overflows. |
| |
| 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 <= var1 <= 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. |
|___________________________________________________________________________|
*/
static_vo Word16 shl (Word16 var1, Word16 var2)
{
Word16 var_out;
Word32 result;
if (var2 < 0)
{
if (var2 < -16)
var2 = -16;
var_out = var1 >> ((Word16)-var2);
}
else
{
if (var2 > 15 && var1 != 0)
{
var_out = (Word16)((var1 > 0) ? MAX_16 : MIN_16);
}
else
{
result = (Word32) var1 *((Word32) 1 << var2);
if ((result != (Word32) ((Word16) result))) {
var_out = (Word16)((var1 > 0) ? MAX_16 : MIN_16);
} else {
var_out = extract_l (result);
}
}
}
return (var_out);
}
/*___________________________________________________________________________
| |
| Function Name : shr |
| |
| Purpose : |
| |
| Arithmetically shift the 16 bit input var1 right var2 positions with |
| sign extension. If var2 is negative, arithmetically shift var1 left by |
| -var2 with sign extension. Saturate the result in case of underflows or |
| overflows. |
| |
| 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 <= var1 <= 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. |
|___________________________________________________________________________|
*/
static_vo Word16 shr (Word16 var1, Word16 var2)
{
Word16 var_out;
if (var2 < 0)
{
if (var2 < -16)
var2 = -16;
var_out = shl(var1, (Word16)-var2);
}
else
{
if (var2 >= 15)
{
var_out = (Word16)((var1 < 0) ? -1 : 0);
}
else
{
if (var1 < 0)
{
var_out = (Word16)(~((~var1) >> var2));
}
else
{
var_out = (Word16)(var1 >> var2);
}
}
}
return (var_out);
}
/*___________________________________________________________________________
| |
| Function Name : mult |
| |
| Purpose : |
| |
| Performs the multiplication of var1 by var2 and gives a 16 bit result |
| which is scaled i.e.: |
| mult(var1,var2) = extract_l(L_shr((var1 times var2),15)) and |
| mult(-32768,-32768) = 32767. |
| |
| 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 <= var1 <= 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. |
|___________________________________________________________________________|
*/
static_vo Word16 mult (Word16 var1, Word16 var2)
{
Word16 var_out;
Word32 L_product;
L_product = (Word32) var1 *(Word32) var2;
L_product = (L_product & (Word32) 0xffff8000L) >> 15;
if (L_product & (Word32) 0x00010000L)
L_product = L_product | (Word32) 0xffff0000L;
var_out = saturate (L_product);
return (var_out);
}
/*___________________________________________________________________________
| |
| Function Name : L_mult |
| |
| Purpose : |
| |
| L_mult is the 32 bit result of the multiplication of var1 times var2 |
| with one shift left i.e.: |
| L_mult(var1,var2) = L_shl((var1 times var2),1) and |
| L_mult(-32768,-32768) = 2147483647. |
| |
| 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 <= var1 <= 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. |
|___________________________________________________________________________|
*/
static_vo Word32 L_mult (Word16 var1, Word16 var2)
{
Word32 L_var_out;
L_var_out = (Word32) var1 *(Word32) var2;
if (L_var_out != (Word32) 0x40000000L)
{
L_var_out *= 2;
}
else
{
L_var_out = MAX_32;
}
return (L_var_out);
}
/*___________________________________________________________________________
| |
| Function Name : round |
| |
| Purpose : |
| |
| Round the lower 16 bits of the 32 bit input number into the MS 16 bits |
| with saturation. Shift the resulting bits right by 16 and return the 16 |
| bit number: |
| round(L_var1) = extract_h(L_add(L_var1,32768)) |
| |
| Complexity weight : 1 |
| |
| Inputs : |
| |
| L_var1 |
| 32 bit long signed integer (Word32 ) whose value falls in the |
| range : 0x8000 0000 <= L_var1 <= 0x7fff ffff. |
| |
| Outputs : |
| |
| none |
| |
| Return Value : |
| |
| var_out |
| 16 bit short signed integer (Word16) whose value falls in the |
| range : 0xffff 8000 <= var_out <= 0x0000 7fff. |
|___________________________________________________________________________|
*/
static_vo Word16 voround (Word32 L_var1)
{
Word16 var_out;
Word32 L_rounded;
L_rounded = L_add (L_var1, (Word32) 0x00008000L);
var_out = extract_h (L_rounded);
return (var_out);
}
/*___________________________________________________________________________
| |
| Function Name : L_mac |
| |
| Purpose : |
| |
| Multiply var1 by var2 and shift the result left by 1. Add the 32 bit |
| result to L_var3 with saturation, return a 32 bit result: |
| L_mac(L_var3,var1,var2) = L_add(L_var3,L_mult(var1,var2)). |
| |
| Complexity weight : 1 |
| |
| Inputs : |
| |
| L_var3 32 bit long signed integer (Word32) whose value falls in the |
| range : 0x8000 0000 <= L_var3 <= 0x7fff ffff. |
| |
| 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 <= var1 <= 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. |
|___________________________________________________________________________|
*/
static_vo Word32 L_mac (Word32 L_var3, Word16 var1, Word16 var2)
{
Word32 L_var_out;
Word32 L_product;
L_product = ((var1 * var2) << 1);
L_var_out = L_add (L_var3, L_product);
return (L_var_out);
}
/*___________________________________________________________________________
| |
| Function Name : L_msu |
| |
| Purpose : |
| |
| Multiply var1 by var2 and shift the result left by 1. Subtract the 32 |
| bit result to L_var3 with saturation, return a 32 bit result: |
| L_msu(L_var3,var1,var2) = L_sub(L_var3,L_mult(var1,var2)). |
| |
| Complexity weight : 1 |
| |
| Inputs : |
| |
| L_var3 32 bit long signed integer (Word32) whose value falls in the |
| range : 0x8000 0000 <= L_var3 <= 0x7fff ffff. |
| |
| 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 <= var1 <= 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. |
|___________________________________________________________________________|
*/
static_vo Word32 L_msu (Word32 L_var3, Word16 var1, Word16 var2)
{
Word32 L_var_out;
Word32 L_product;
L_product = (var1 * var2)<<1;
L_var_out = L_sub (L_var3, L_product);
return (L_var_out);
}
/*___________________________________________________________________________
| |
| Function Name : L_add |
| |
| Purpose : |
| |
| 32 bits addition of the two 32 bits variables (L_var1+L_var2) with |
| overflow control and saturation; the result is set at +2147483647 when |
| overflow occurs or at -2147483648 when underflow occurs. |
| |
| Complexity weight : 2 |
| |
| Inputs : |
| |
| L_var1 32 bit long signed integer (Word32) whose value falls in the |
| range : 0x8000 0000 <= L_var3 <= 0x7fff ffff. |
| |
| L_var2 32 bit long signed integer (Word32) whose value falls in the |
| range : 0x8000 0000 <= L_var3 <= 0x7fff ffff. |
| |
| 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. |
|___________________________________________________________________________|
*/
__attribute__((no_sanitize("integer")))
static_vo Word32 L_add (Word32 L_var1, Word32 L_var2)
{
Word32 L_var_out;
L_var_out = L_var1 + L_var2;
if (((L_var1 ^ L_var2) & MIN_32) == 0)
{
if ((L_var_out ^ L_var1) & MIN_32)
{
L_var_out = (L_var1 < 0) ? MIN_32 : MAX_32;
}
}
return (L_var_out);
}
/*___________________________________________________________________________
| |
| Function Name : L_sub |
| |
| Purpose : |
| |
| 32 bits subtraction of the two 32 bits variables (L_var1-L_var2) with |
| overflow control and saturation; the result is set at +2147483647 when |
| overflow occurs or at -2147483648 when underflow occurs. |
| |
| Complexity weight : 2 |
| |
| Inputs : |
| |
| L_var1 32 bit long signed integer (Word32) whose value falls in the |
| range : 0x8000 0000 <= L_var3 <= 0x7fff ffff. |
| |
| L_var2 32 bit long signed integer (Word32) whose value falls in the |
| range : 0x8000 0000 <= L_var3 <= 0x7fff ffff. |
| |
| 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. |
|___________________________________________________________________________|
*/
__attribute__((no_sanitize("integer")))
static_vo Word32 L_sub (Word32 L_var1, Word32 L_var2)
{
Word32 L_var_out;
L_var_out = L_var1 - L_var2;
if (((L_var1 ^ L_var2) & MIN_32) != 0)
{
if ((L_var_out ^ L_var1) & MIN_32)
{
L_var_out = (L_var1 < 0L) ? MIN_32 : MAX_32;
}
}
return (L_var_out);
}
/*___________________________________________________________________________
| |
| Function Name : mult_r |
| |
| Purpose : |
| |
| Same as mult with rounding, i.e.: |
| mult_r(var1,var2) = extract_l(L_shr(((var1 * var2) + 16384),15)) and |
| mult_r(-32768,-32768) = 32767. |
| |
| Complexity weight : 2 |
| |
| 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 <= var1 <= 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. |
|___________________________________________________________________________|
*/
static_vo Word16 mult_r (Word16 var1, Word16 var2)
{
Word16 var_out;
Word32 L_product_arr;
L_product_arr = (Word32) var1 *(Word32) var2; /* product */
L_product_arr += (Word32) 0x00004000L; /* round */
L_product_arr &= (Word32) 0xffff8000L;
L_product_arr >>= 15; /* shift */
if (L_product_arr & (Word32) 0x00010000L) /* sign extend when necessary */
{
L_product_arr |= (Word32) 0xffff0000L;
}
var_out = saturate (L_product_arr);
return (var_out);
}
/*___________________________________________________________________________
| |
| Function Name : L_shl |
| |
| Purpose : |
| |
| Arithmetically shift the 32 bit input L_var1 left var2 positions. Zero |
| fill the var2 LSB of the result. If var2 is negative, arithmetically |
| shift L_var1 right by -var2 with sign extension. Saturate the result in |
| case of underflows or overflows. |
| |
| Complexity weight : 2 |
| |
| Inputs : |
| |
| L_var1 32 bit long signed integer (Word32) whose value falls in the |
| range : 0x8000 0000 <= L_var3 <= 0x7fff ffff. |
| |
| var2 |
| 16 bit short signed integer (Word16) whose value falls in the |
| range : 0xffff 8000 <= var1 <= 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. |
|___________________________________________________________________________|
*/
static_vo Word32 L_shl (Word32 L_var1, Word16 var2)
{
Word32 L_var_out = 0L;
if (var2 <= 0)
{
if (var2 < -32)
var2 = -32;
L_var_out = (L_var1 >> (Word16)-var2);
}
else
{
for (; var2 > 0; var2--)
{
if (L_var1 > (Word32) 0X3fffffffL)
{
L_var_out = MAX_32;
break;
}
else
{
if (L_var1 < (Word32) 0xc0000000L)
{
//Overflow = 1;
L_var_out = MIN_32;
break;
}
}
L_var1 *= 2;
L_var_out = L_var1;
}
}
return (L_var_out);
}
static_vo Word32 L_shl2(Word32 L_var1, Word16 var2)
{
Word32 L_var_out = 0L;
for (; var2 > 0; var2--)
{
if (L_var1 > (Word32) 0X3fffffffL)
{
L_var_out = MAX_32;
break;
}
else
{
if (L_var1 < (Word32) 0xc0000000L)
{
L_var_out = MIN_32;
break;
}
}
L_var1 *= 2 ;
L_var_out = L_var1;
}
return (L_var_out);
}
/*___________________________________________________________________________
| |
| Function Name : L_shr |
| |
| Purpose : |
| |
| Arithmetically shift the 32 bit input L_var1 right var2 positions with |
| sign extension. If var2 is negative, arithmetically shift L_var1 left |
| by -var2 and zero fill the -var2 LSB of the result. Saturate the result |
| in case of underflows or overflows. |
| |
| Complexity weight : 2 |
| |
| Inputs : |
| |
| L_var1 32 bit long signed integer (Word32) whose value falls in the |
| range : 0x8000 0000 <= L_var3 <= 0x7fff ffff. |
| |
| var2 |
| 16 bit short signed integer (Word16) whose value falls in the |
| range : 0xffff 8000 <= var1 <= 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. |
|___________________________________________________________________________|
*/
static_vo Word32 L_shr (Word32 L_var1, Word16 var2)
{
Word32 L_var_out;
if (var2 < 0)
{
if (var2 < -32)
var2 = -32;
L_var_out = L_shl2(L_var1, (Word16)-var2);
}
else
{
if (var2 >= 31)
{
L_var_out = (L_var1 < 0L) ? -1 : 0;
}
else
{
if (L_var1 < 0)
{
L_var_out = ~((~L_var1) >> var2);
}
else
{
L_var_out = L_var1 >> var2;
}
}
}
return (L_var_out);
}
/*___________________________________________________________________________
| |
| Function Name : L_shr_r |
| |
| Purpose : |
| |
| Same as L_shr(L_var1,var2) but with rounding. Saturate the result in |
| case of underflows or overflows : |
| - If var2 is greater than zero : |
| if (L_sub(L_shl(L_shr(L_var1,var2),1),L_shr(L_var1,sub(var2,1))))|
| is equal to zero |
| then |
| L_shr_r(L_var1,var2) = L_shr(L_var1,var2) |
| else |
| L_shr_r(L_var1,var2) = L_add(L_shr(L_var1,var2),1) |
| - If var2 is less than or equal to zero : |
| L_shr_r(L_var1,var2) = L_shr(L_var1,var2). |
| |
| Complexity weight : 3 |
| |
| Inputs : |
| |
| L_var1 |
| 32 bit long signed integer (Word32) whose value falls in the |
| range : 0x8000 0000 <= var1 <= 0x7fff ffff. |
| |
| var2 |
| 16 bit short signed integer (Word16) whose value falls in the |
| range : 0xffff 8000 <= var1 <= 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. |
|___________________________________________________________________________|
*/
static_vo Word32 L_shr_r (Word32 L_var1, Word16 var2)
{
Word32 L_var_out;
if (var2 > 31)
{
L_var_out = 0;
}
else
{
L_var_out = L_shr (L_var1, var2);
if (var2 > 0)
{
if ((L_var1 & ((Word32) 1 << (var2 - 1))) != 0)
{
L_var_out++;
}
}
}
return (L_var_out);
}
/*___________________________________________________________________________
| |
| Function Name : norm_s |
| |
| Purpose : |
| |
| Produces the number of left shift needed to normalize the 16 bit varia- |
| ble var1 for positive values on the interval with minimum of 16384 and |
| maximum of 32767, and for negative values on the interval with minimum |
| of -32768 and maximum of -16384; in order to normalize the result, the |
| following operation must be done : |
| norm_var1 = shl(var1,norm_s(var1)). |
| |
| Complexity weight : 15 |
| |
| Inputs : |
| |
| var1 |
| 16 bit short signed integer (Word16) whose value falls in the |
| range : 0xffff 8000 <= var1 <= 0x0000 7fff. |
| |
| Outputs : |
| |
| none |
| |
| Return Value : |
| |
| var_out |
| 16 bit short signed integer (Word16) whose value falls in the |
| range : 0x0000 0000 <= var_out <= 0x0000 000f. |
|___________________________________________________________________________|
*/
static_vo Word16 norm_s (Word16 var1)
{
Word16 var_out = 0;
if (var1 == 0)
{
var_out = 0;
}
else
{
if (var1 == -1)
{
var_out = 15;
}
else
{
if (var1 < 0)
{
var1 = (Word16)~var1;
}
for (var_out = 0; var1 < 0x4000; var_out++)
{
var1 <<= 1;
}
}
}
return (var_out);
}
/*___________________________________________________________________________
| |
| Function Name : div_s |
| |
| Purpose : |
| |
| Produces a result which is the fractional integer division of var1 by |
| var2; var1 and var2 must be positive and var2 must be greater or equal |
| to var1; the result is positive (leading bit equal to 0) and truncated |
| to 16 bits. |
| If var1 = var2 then div(var1,var2) = 32767. |
| |
| Complexity weight : 18 |
| |
| Inputs : |
| |
| var1 |
| 16 bit short signed integer (Word16) whose value falls in the |
| range : 0x0000 0000 <= var1 <= var2 and var2 != 0. |
| |
| var2 |
| 16 bit short signed integer (Word16) whose value falls in the |
| range : var1 <= var2 <= 0x0000 7fff and var2 != 0. |
| |
| Outputs : |
| |
| none |
| |
| Return Value : |
| |
| var_out |
| 16 bit short signed integer (Word16) whose value falls in the |
| range : 0x0000 0000 <= var_out <= 0x0000 7fff. |
| It's a Q15 value (point between b15 and b14). |
|___________________________________________________________________________|
*/
static_vo Word16 div_s (Word16 var1, Word16 var2)
{
Word16 var_out = 0;
Word16 iteration;
Word32 L_num;
Word32 L_denom;
if ((var1 < 0) || (var2 < 0))
{
var_out = MAX_16;
return var_out;
}
if (var2 == 0)
{
var_out = MAX_16;
return var_out;
}
if (var1 == 0)
{
var_out = 0;
}
else
{
if (var1 == var2)
{
var_out = MAX_16;
}
else
{
L_num = L_deposit_l (var1);
L_denom = L_deposit_l(var2);
for (iteration = 0; iteration < 15; iteration++)
{
var_out <<= 1;
L_num <<= 1;
if (L_num >= L_denom)
{
L_num -= L_denom;
var_out += 1;
}
}
}
}
return (var_out);
}
/*___________________________________________________________________________
| |
| Function Name : norm_l |
| |
| Purpose : |
| |
| Produces the number of left shifts needed to normalize the 32 bit varia-|
| ble L_var1 for positive values on the interval with minimum of |
| 1073741824 and maximum of 2147483647, and for negative values on the in-|
| terval with minimum of -2147483648 and maximum of -1073741824; in order |
| to normalize the result, the following operation must be done : |
| norm_L_var1 = L_shl(L_var1,norm_l(L_var1)). |
| |
| Complexity weight : 30 |
| |
| Inputs : |
| |
| L_var1 |
| 32 bit long signed integer (Word32) whose value falls in the |
| range : 0x8000 0000 <= var1 <= 0x7fff ffff. |
| |
| Outputs : |
| |
| none |
| |
| Return Value : |
| |
| var_out |
| 16 bit short signed integer (Word16) whose value falls in the |
| range : 0x0000 0000 <= var_out <= 0x0000 001f. |
|___________________________________________________________________________|
*/
static_vo Word16 norm_l (Word32 L_var1)
{
Word16 var_out = 0;
if (L_var1 != 0)
{
var_out = 31;
if (L_var1 != (Word32) 0xffffffffL)
{
L_var1 ^= (L_var1 >>31);
for (var_out = 0; L_var1 < (Word32) 0x40000000L; var_out++)
{
L_var1 <<= 1;
}
}
}
return (var_out);
}
#endif //__BASIC_OP_H__