The conditional branch instructions test the condition code and branch if the condition code matches the specific instruction used. The conditional branch instructions are:
| Instruction | Meaning | Value When Branch is Taken | |
|---|---|---|---|
| Relationship of Operands | Condition Code | ||
| BH | branch on high | operand1 > operand2 | 10 |
| BL | branch on low | operand1 < operand2 | 01 |
| BE | branch on equal | operand1 == operand2 | 00 |
| BNE | branch on not equal | operand1 != operand2 | 10 or 01 |
| BNH | branch on not high | operand1 <= operand2 | 00 or 01 |
| BNL | branch on not low | operand1 >= operand2 | 00 or 10 |
The following examples show how to use branch instructions to implement some if structures:
| Pseudocode | Assembler |
|---|---|
if A > B . . (1) . endif . . (2) . |
CLC A,B
BH ONE
B CONT
ONE .
. (1)
.
CONT .
. (2)
. |
if A > B . . (1) . endif . . (2) . |
CLC A,B
BNH CONT
.
. (1)
.
CONT .
. (2)
. |
if A == B . . (1) . else . . (2) . endif . . (3) . |
CLC A,B
BE EQUAL
.
. (2)
.
B AFTER
EQUAL .
. (1)
.
AFTER .
. (3)
. |
if A > B || C <= D . . (1) . else . . (2) . endif . . (3) . |
CLC A,B
BH TRUE
CLC C,D
BNH TRUE
.
. (2)
.
B AFTER
TRUE .
. (1)
.
AFTER .
. (3)
. |
if A != B . . (1) . else if C > D . . (2) . else . . (3) . endif . . (4) . |
CLC A,B
BNE ONE
CLC C,D
BH TWO
.
. (3)
.
B AFTER
ONE .
. (1)
.
B AFTER
TWO .
. (2)
.
AFTER .
. (4)
. |
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