SH-2A Datasheet, PDF (167/501 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperH™ RISC engine Family

Section 6 Instruction Descriptions
Operation
SHLD (int m,n) /* SHLD Rm,Rn */
{
int sgn = R[m] & 0x80000000;
if (sgn == 0)
R[n] <<= (R[m] & 0x0000001F);
else if ((R[m] & 0x0000001F) == 0)
R[n] = 0;
else
R[n]=(unsigned)R[n] >> ((~R[m] & 0x0000001F)+1);
PC+=2;
}
Examples:
SHLD R1, R2
SHLD R3, R4
; Before execution: R1 = H'FFFFFFEC, R2 = H'80180000
; After execution: R1 = H'FFFFFFEC, R2 = H'00000801
; Before execution: R3 = H'00000014, R2 = H'FFFFF801
; After execution: R3 = H'00000014, R2 = H'80100000
Rev. 3.00 Jul 08, 2005 page 153 of 484
REJ09B0051-0300