1. An integrated circuit device comprising:
a first table for storing local branch prediction information;
a second table for storing global branch prediction information;
circuitry configured to:
receive a branch instruction;
store local branch prediction information for the branch instruction in the first table including a local predictability value for the local branch prediction information; and
store global branch prediction information for the branch instruction in the second table only if the local predictability value is below a threshold value of predictability.
2. The integrated circuit device of claim 1, wherein the local branch prediction information includes a prediction bit corresponding to a predicted outcome of the branch instruction.
3. The integrated circuit device of claim 2, wherein the predicted outcome of the branch instruction is one of taking a branch of the branch instruction and not-taking a branch of the branch instruction.
4. The integrated circuit device of claim 1, wherein the global branch prediction information includes one or more outcome bits for one or more other branch instructions and a corresponding prediction bit corresponding to the predicted outcome of the branch instruction.
5. The integrated circuit device of claim 1, wherein the global branch prediction information includes a global predictability value.
6. The integrated circuit device of claim 5, wherein the circuitry is further configured to:
use the local branch prediction information to predict an outcome of the branch instruction if the local predictability value is greater than the global predictability value; and
use the global branch prediction information to predict the outcome of the branch instruction if the global predictability value is greater than the local predictability value.
7. The integrated circuit device of claim 1, wherein the local predictability value indicates a frequency of previous correct predictions for the branch instruction.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
What is claimed is:
1. A cooling apparatus for a linear motor comprising:
a U shaped stator back iron;
a stator having a plurality of permanent magnets installed on inner facing surfaces of the stator back iron;
a coil unit positioned between the stator and the permanent magnets with a predetermined gap;
a movable unit having a movable unit back iron fixed on the coil unit, the movable back iron having at least one first air hole formed therein in a longitudinal direction and a first air nozzle linked to the first air hole for injecting cooling air from the top portion of the coil unit to the bottom portion; and
a frame aligned at the lower portion of the coil unit having a second air hole formed in a longitudinal direction thereof for receiving the cooling air and a second air nozzle linked to the second air hole for injecting the cooling air from the bottom portion of the coil unit to the top portion.
2. The cooling apparatus according to claim 1, wherein the frame has a U shape, both side vertical units of which being connected respectively to the front and rear portions of the movable unit back iron, thereby injecting cooling air from both sides of the second air hole and the first air hole.
3. The cooling apparatus according to claim 1, wherein the second air hole is formed at one center portion of the frame, and the second air nozzle is protruded from both sides of the second air hole, for injecting the cooling air into both sides of the coil unit.