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For jpr %rb
jpr
%rb
A signed 24-bit relative value is specified for rb.
The jump address is configured as follows:
{rb(23:1), 0}
%rb
PC
PC
The least significant bit in the rb register is always handled as 0.
The range of addresses to which jumped is (PC - 8,388,606) to (PC + 8,388,608).
The above range of addresses to which jumped is a theoretical value, and is actually limited by the range of
memory areas used.
Branch conditions
The jpr instruction is an unconditional jump instruction that always cause the program to branch.
Instructions with names beginning with jr are conditional jump instructions for which the respective branch
conditions are set by a combination of flags, so that only when the conditions are satisfied do they cause the
program to branch to a specified address. The program does not branch unless the conditions are satisfied.
The conditional jump instructions basically use the result of the comparison of two values by the cmp instruc-
tion to determine whether to branch. For this reason, the name of each instruction includes a character that rep-
resents relative magnitude.
The types of conditional jump instructions and branch conditions are listed in Table 5.8.1.1.
Table 5.8.1.1 Conditional Jump Instructions and Branch Conditions
Instruction
Greater Than
jrgt
Greater or Equal
jrge
Less Than
jrlt
Less or Equal
jrle
Unsigned, Greater Than
jrugt
Unsigned, Greater or Equal
jruge
Unsigned, Less Than
jrult
Unsigned, Less or Equal
jrule
Equal
jreq
Not Equal
jrne
(2) Absolute jump instructions
The absolute jump instruction jpa causes the program to unconditionally branch to the location indicated by
the content of a specified general-purpose register (rb) or an immediate imm7 (can be extended to imm20 or
imm24 using the ext instruction) as the absolute address. When the content of the rb register or the immediate
is loaded into the PC, its least significant bit is always made 0.
jpa %rb
S1C17 CORE MANUAL
(Rev. 1.2)
23
S
Current address
Branch destination address
Flag condition
!Z & !(N ^ V)
!(N ^ V)
Z | (N ^ V)
!Z & !C
23
rb
PC
Seiko Epson Corporation
D(23:1)
+
2
+
Comparison of A:B
A > B
A ≥ B
N ^ V
A < B
A ≤ B
A > B
A ≥ B
!C
C
A < B
A ≤ B
Z | C
Z
A = B
A ≠ B
!Z
Comparison of A:B made when "cmp A,B"
D(23:1)
Branch destination address
5 INSTRUCTION SET
1
0
X
0
0
Remark
Used to compare
signed data
Used to compare
unsigned data
1
0
X
0
5-19
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