📄 basic_op.c
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| 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) = 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. |
|___________________________________________________________________________|
*/
/*inline 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
{
Overflow = 1;
L_var_out = MAX_32;
}
return(L_var_out);
}*/
/*___________________________________________________________________________
| |
| Function Name : negate |
| |
| Purpose : |
| |
| Negate var1 with saturation, saturate in the case where input is -32768:|
| negate(var1) = sub(0,var1). |
| |
| Complexity weight : 1 |
| |
| 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 : 0xffff 8000 <= var_out <= 0x0000 7fff. |
|___________________________________________________________________________|
*/
/*inline Word16 negate(Word16 var1)
{
Word16 var_out;
var_out = (var1 == MIN_16) ? MAX_16 : -var1;
return(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 +214783647 when |
| overflow occurs or at -214783648 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. |
|___________________________________________________________________________|
*/
/*inline 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;
Overflow = 1;
}
}
return(L_var_out);
}*/
/*___________________________________________________________________________
| |
| Function Name : round |
| |
| Purpose : |
| |
| Round the lower 16 bits of the 32 bit input number into its 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. |
|___________________________________________________________________________|
*/
/*inline Word16 round(Word32 L_var1)
{
Word16 var_out;
Word32 L_arrondi;
L_arrondi = L_add(L_var1, (Word32)0x00008000);
var_out = extract_h(L_arrondi);
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. |
|___________________________________________________________________________|
*/
/*inline Word32 L_mac(Word32 L_var3, Word16 var1, Word16 var2)
{
Word32 L_var_out;
Word32 L_produit;
L_produit = L_mult(var1,var2);
L_var_out = L_add(L_var3,L_produit);
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 +214783647 when |
| overflow occurs or at -214783648 when underflow occurs. |
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