Renesas SH7781 - Manual (Page 79)

3. Instruction Set
Rev.1.00 Jan. 10, 2008 Page 49 of 1658
REJ09B0261-0100
Addressing
Mode Instruction
Format
Effective Address Calculation Method
Calculation
Formula
GBR indirect
with displace-
ment @(disp:8,
GBR) Effective address is register GBR contents with
8-bit displacement disp added. After disp is
zero-extended, it is multiplied by 1 (byte), 2 (word),
or 4 (longword), according to the operand size.
GBR
1/2/4
GBR
+ disp Ч 1/2/4
+
Ч
disp
(zero-extended)
Byte: GBR +
disp
→ EA
Word: GBR +
disp
× 2 → EA
Longword:
GBR + disp
×
4
→ EA
Indexed GBR
indirect @(R0, GBR) Effective address is sum of register GBR and R0
contents.
GBR
R0
GBR + R0 +
GBR + R0
→
EA
PC-relative
with
displacement @(disp:8, PC) Effective address is PC + 4 with 8-bit displacement
disp added. After disp is zero-extended, it is
multiplied by 2 (word), or 4 (longword), according
to the operand size. With a longword operand,
the lower 2 bits of PC are masked.
PC
H'FFFF FFFC
PC + 4 + disp
× 2
or PC &
H'FFFF FFFC
+ 4 + disp Ч 4
+
4
2/4
Ч
+
& *
disp
(zero-extended)
* With longword operand
Word: PC + 4
+ disp
× 2 →
EA
Longword:
PC & H'FFFF
FFFC + 4 +
disp
× 4 → EA