Intel ARCHITECTURE IA-32 - Manual (Page 93)

General Optimization Guidelines
2
2-21
Examples 2-6, Example 2-7 provide basic rules for a static prediction
algorithm.
In Example 2-6, the backward branch ( JC Begin ) is not in the BTB the
first time through, therefore, the BTB does not issue a prediction. The
static predictor, however, will predict the branch to be taken, so a
misprediction will not occur.
The first branch instruction ( JC Begin ) in Example 2-7 segment is a
conditional forward branch. It is not in the BTB the first time through,
but the static predictor will predict the branch to fall through.
The static prediction algorithm correctly predicts that the Call
Convert instruction will be taken, even before the branch has any
branch history in the BTB.
Example 2-6 Static Taken Prediction Example
Begin: mov eax, mem32
and eax, ebx
imul eax, edx
shld eax, 7
jc Begin
Example 2-7 Static Not-Taken Prediction Example
mov eax, mem32
and eax, ebx
imul eax, edx
shld eax, 7
jc Begin
mov eax, 0
Begin: call Convert