Electrical computers and digital processing systems: processing – Processing control – Branching
Reexamination Certificate
2007-11-13
2007-11-13
Ellis, Richard L. (Department: 2183)
Electrical computers and digital processing systems: processing
Processing control
Branching
C712S234000
Reexamination Certificate
active
10920766
ABSTRACT:
A first tag is assigned to a branch instruction. Dependent on the type of branch instruction, a second tag is assigned to an instruction in the branch delay slot of the branch instruction. The second tag may equal the first tag if the branch delay slot is unconditional for that branch, and may equal a different tag if the branch delay slot is conditional for the branch. If the branch is mispredicted, the first tag is broadcast to pipeline stages that may have speculative instructions, and the first tag is compared to tags in the pipeline stages. If the tag in a pipeline stage matches the first tag, the instruction is not cancelled. If the tag mismatches, the instruction is cancelled.
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Broadcom Corporation
Ellis Richard L.
Fong Vincent
Garlick & Harrison & Markison
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