EXAMPLE
Example Instruction
13-38
Syntax
INST
src, dst
or
INST1
src2, dst1
|| INST2
src3, dst2
Each instruction begins with an assembler syntax expression. You can place
labels either before the command (instruction mnemonic) on the same line or
on the preceding line in the first column. The optional comment field that con-
cludes the syntax is not included in the syntax expression. Space(s) are
required between each field (label, command, operand, and comment fields).
The syntax examples illustrate the common one-line syntax and the two-line
syntax used in parallel addressing. Note that the two vertical bars || that indicate
a parallel addressing pair can be placed anywhere before the mnemonic on the
second line. The first instruction in the pair can have a label, but the second
instruction cannot have a label.
Operation
|
src |
→
dst
or
|
src2 |
→
dst1
||
src3
→
dst2
The instruction operation sequence describes the processing that occurs when
the instruction is executed. For parallel instructions, the operation sequence is
performed in parallel. Conditional effects of status-register-specified modes are
listed for such conditional instructions as B
cond.
Operands
src general-addressing modes (G):
0 0
register (R
n, 0
≤
n
≤
27)
0 1
direct
1 0
indirect
1 1
immediate
dst
register (R
n, 0
≤
n
≤
27)
or
src2
indirect (
disp = 0, 1, IR0, IR1)
dst1
register (R
n1, 0
≤
n1
≤
7)
src3
register (R
n2, 0
≤
n2
≤
7)
dst2
indirect (
disp = 0, 1, IR0, IR1)
Operands are defined according to the addressing mode and/or the type
of addressing used. Note that indirect addressing uses displacements and
the index registers. See Chapter 6 for detailed information on addressing.