Editing Jump threading (section)

==Examples==
The following [[pseudocode]] demonstrates when a jump may be threaded.

    10. a = SomeNumber();
    20. IF a > 10 GOTO 50
    ...
    50. IF a > 0 GOTO 100
    ...

The jump on line 50 will always be taken if the jump on line 20 is taken. Therefore, for as long as line 100 is within the reachable range of the jump (or the size of the jump doesn't matter), the jump on line 20 may safely be modified to jump directly to line 100.

Another example shows jump threading of 2 partial overlap conditions:

<syntaxhighlight lang="cpp" line="1">
void baz(bool x, bool y, bool z) {
    if (x && y)
        bar();
    if (y || z)
        foo();
}
</syntaxhighlight>

The above can be transformed into:

<syntaxhighlight lang="cpp" line="1">
void baz(bool x, bool y, bool z) {
    if (x && y) {
        bar();
        goto jmp;
    }
    if (y || z) {
jmp:
        foo();
    }
}
</syntaxhighlight>

If the first branch is taken, <code>x</code> and <code>y</code> are both [[Truth value|true]] ([[logical conjunction]]), hence evaluation of [[Expression (computer science)|expression]] <code>y || z</code> is not needed ([[logical disjunction]]). Therefore, a jump to [[Label (computer science)|label]] <code>jmp</code> is performed.<ref name="redhat"/>