Renesas M32R-FPU - Manual (Page 131)

3
3-93 M32R-FPU Software Manual (Rev.1.01)
RACH RACH
DSP function instruction
Round accumulator halfword
[Mnemonic]
RACH
[Function]
Saturation Process
{ signed64bit tmp;
tmp = ( signed64bit ) accumulator << 1;
tmp = tmp + 0x0000 0000 8000 0000;
if( 0x0000 7fff 0000 0000 < tmp )
accumulator = 0x0000 7fff 0000 0000;
else if( tmp < 0xffff 8000 0000 0000 )
accumulator = 0xffff 8000 0000 0000;
else
accumulator = tmp & 0xffff ffff 0000 0000; }
[Description]
RACH rounds the contents in the accumulator to halfword size and stores the result in the
accumulator.
The condition bit (C) is unchanged.
[EIT occurrence]
None
[Encoding]
RACH 0000 0101 0000 1000
INSTRUCTIONS
3.2 Instruction description