GMS30C2216 Datasheet, PDF (202/320 Pages) Hynix Semiconductor – 16/32 BIT RISC/DSP

A-30
Check Zero
Appendix A. Instruction Set Details
CHKZ
Format:
RR format
15
OP-code
0000 00
10 9
d
87
s
Rd-code
43
0
Rs-code
s = 0: Rs-code encoded G0..G15 for Rs
s = 1: Rs-code encoded L0..L15 for Rs
d = 0: Rd-code encoded G0..G15 for Rd
d = 1: Rd-code encoded L0..L15 for Rd
Notation:
CHK Rd, 0
Description:
A destination operand is checked and a trap to a Range Error occurs if the destination
operand is zero.
All registers and all condition flags remain unchanged. All operands are interpreted as
unsigned integers.
CHKZ shares its basic OP-code with CHK, it is differentiated by denoting the SR as source
operand.
CHKZ may be used to trap on uninitialized pointers with the value zero.
Operation:
If Rs denotes SR and Rd = 0 then
trap -> Range Error
Exceptions:
Range Error.