Blezl, Branch on less than or equal to zero likely – NEC Network Controller uPD98502 User Manual
Page 457

APPENDIX A MIPS III INSTRUCTION SET DETAILS
Preliminary User’s Manual S15543EJ1V0UM
457
BLEZL
Branch On Less Than Or Equal To Zero Likely
BLEZL
rs
BLEZL
0 1 0 1 1 0
0
0 0 0 0 0
offset
31
26 25
21 20
16 15
0
6
5
5
16
Format:
BLEZL rs, offset
Description:
A branch target address is computed from the sum of the address of the instruction in the delay slot and the 16-bit
offset, shifted left two bits and sign-extended. The contents of general register rs is compared to zero. If the
contents of general register
rs are zero or smaller than zero, then the program branches to the target address, with
a delay of one instruction.
If the conditional branch is not taken, the instruction in the branch delay slot is nullified.
Operation:
32
T:
target
← (offset
15
)
14
|| offset || 0
2
condition
← (GPR [rs]
31
= 1) or (GPR [rs] = 0
32
)
T+1: if condition then
PC
← PC + target
else
NullifyCurrentInstruction
endif
64
T:
target
← (offset
15
)
46
|| offset || 0
2
condition
← (GPR [rs]
63
= 1) or (GPR [rs] = 0
64
)
T+1: if condition then
PC
← PC + target
else
NullifyCurrentInstruction
endif
Exceptions:
None