| |||
| Home > Compiler-specific Features > Instruction intrinsics > __smuadx intrinsic | |||
This intrinsic inserts an SMUADX instruction
into the instruction stream generated by the compiler. It enables
you to exchange the halfwords of the second operand, perform two 16-bit
signed integer multiplications, and add the products together. Exchanging
the halfwords of the second operand produces top × bottom and bottom × top multiplication.
The Q flag is set if the addition overflows. The multiplications
cannot overflow.
unsigned int__smuadx(unsigned intval1, unsigned intval2)
Where:
val1holds the first halfword operands for each multiplication
val2holds the second halfword operands for each multiplication.
The __smuadx intrinsic returns the products
of the two 16-bit signed multiplications.
Example:
unsigned int exchange_dual_multiply_prods(unsigned int val1, unsigned int val2)
{
unsigned int res;
res = __smuadx(val1,val2); /* val2[31:16][15:0] = val2[15:0][31:16]
p1 = val1[15:0] × val2[15:0]
p2 = val1[31:16] × val2[31:16]
res[31:0] = p1 + p2
*/
return res;
}
Instruction summary in the Assembler Guide
SMUAD{X} and SMUSD{X} in the Assembler Guide.