Renesas SuperH SH-4A - MULS.W (Multiply as Signed Word): Arithmetic Instruction

Rev. 1.50, 10/04, page 284 of 448
10.1.41 MULS.W (Multiply as Signed Word): Arithmetic Instruction
Format Operation Instruction Code Cycle T Bit
MULS.W Rm,Rn Signed, Rn × Rm → MACL 0010nnnnmmmm1111 1 —
Description: This instruction performs 16-bit multiplication of the contents of general registers
Rn and Rm, and stores the 32-bit result in the MACL register. The multiplication is performed as a
signed arithmetic operation. The contents of MACH are not changed.
Notes: None
Operation:
MULS(long m, long n) /* MULS Rm,Rn */
{
MACL = ((long)(short)R[n]*(long)(short)R[m]);
PC += 2;
}
Example:
MULS.W R0,R1 ;Before execution R0 = H'FFFFFFFE, R1 = H'00005555
;After execution MACL = H'FFFF5556
STS MACL,R0 ;Get operation result