12.18 __shsax intrinsic
This intrinsic inserts a
SHSAX instruction into the instruction stream generated by the compiler.
you to exchange the two halfwords of one operand, perform one signed
16-bit integer subtraction and one signed 16-bit addition, and halve
unsigned int __shsax(unsigned int
, unsigned int
holds the first halfword operands
holds the second halfword operands.
__shsax intrinsic returns:
The halved addition of the low halfword in the first
operand and the high halfword in the second operand, in the low
halfword of the return value.
The halved subtraction of the low halfword in the
second operand from the high halfword in the first operand, in the
high halfword of the return value.
unsigned int exchange_subtract_add_halve(unsigned int val1, unsigned int val2)
unsigned int res;
res = __shsax(val1,val2); /* res[15:0] = (val1[15:0] + val2[31:16]) >> 1
res[31:16] = (val1[31:16] - val2[15:0]) >> 1