Synopsis

int __smlsdx(int16x2 val1,
             int16x2 val2,
             int val3);

Description

__smlsdx inserts a SMLSDX instruction. __smlsdx returns the equivalent of

• res = val1[0] * val2[1] - val1[1] * val2[0] + val3
  
  where [0] is the lower 16 bits and [1] is the upper 16 bits. This operation sets the Q flag if overflow occurs on the addition.