__uhsax intrinsic

This intrinsic inserts a UHSAX instruction into the instruction stream generated by the compiler. It enables you to exchange the halfwords of the second operand, subtract the high halfwords and add the low halfwords, halving the results.

unsigned int __uhsax(unsigned int val1, unsigned int val2)

Where:

val1

holds the first operand for the addition in the low halfword, and the first operand for the subtraction in the high halfword

val2

holds the second operand for the addition in the high halfword, and the second operand for the subtraction in the low halfword.

The __uhsax intrinsic returns:

Example:

unsigned int exchange_subtract_add(unsigned int val1, unsigned int val2)
{
  unsigned int res;

    res = __uhsax(val1,val2); /* res[15:0] = (val1[15:0] + val2[31:16]) >> 1
                                 res[31:16] = (val1[31:16] - val2[15:0]) >> 1
                                */
    return res;
}

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