Power ISA™ Version 2.03 - Power.org

Version 2.03
3.3.3 Fixed-Point Store Instructions
The contents of register RS are stored into the byte,
halfword, word, or doubleword in storage addressed by
EA.
Many of the Store instructions have an “update” form,
in which register RA is updated with the effective
address. For these forms, the following rules apply.
If RA≠0, the effective address is placed into register
RA.
If RS=RA, the contents of register RS are copied to
the target storage element and then EA is placed
into RA (RS).
Store Byte
D-form
Store Byte Indexed
X-form
stb
RS,D(RA)
stbx
RS,RA,RB
38 RS RA D
0 6 11 16 31
if RA = 0 then b 0
else
b (RA)
EA b + EXTS(D)
MEM(EA, 1) (RS) 56:63
Let the effective address (EA) be the sum (RA|0)+ D.
(RS) 56:63 are stored into the byte in storage addressed
by EA.
Special Registers Altered:
None
31 RS RA RB 215 /
0 6 11 16 21 31
if RA = 0 then b 0
else
b (RA)
EA b + (RB)
MEM(EA, 1) (RS) 56:63
Let the effective address (EA) be the sum
(RA|0)+ (RB). (RS) 56:63 are stored into the byte in storage
addressed by EA.
Special Registers Altered:
None
Store Byte with Update
D-form
Store Byte with Update Indexed
X-form
stbu
RS,D(RA)
stbux
RS,RA,RB
39 RS RA D
0 6 11 16 31
EA (RA) + EXTS(D)
MEM(EA, 1) (RS) 56:63
RA EA
Let the effective address (EA) be the sum (RA)+ D.
(RS) 56:63 are stored into the byte in storage addressed
by EA.
EA is placed into register RA.
If RA=0, the instruction form is invalid.
Special Registers Altered:
None
31 RS RA RB 247 /
0 6 11 16 21 31
EA (RA) + (RB)
MEM(EA, 1) (RS) 56:63
RA EA
Let the effective address (EA) be the sum (RA)+ (RB).
(RS) 56:63 are stored into the byte in storage addressed
by EA.
EA is placed into register RA.
If RA=0, the instruction form is invalid.
Special Registers Altered:
None
Chapter 3. Fixed-Point Processor
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