Abstract: A load is executed speculatively as a dismissible load instruction, which does not take exceptions, and a check instruction, which is in the same format as the dismissible load, that when executed determines whether an exception should be taken on the dismissible load. In this manner, a load may be executed speculatively while ensuring that an exception occurs at the same time it would have occurred had the load been executed non-speculatively.

Abstract: A branch operation is processed using a branch predict instruction and an associated branch instruction. The branch predict instruction indicates a predicted direction, a target address, and an instruction address for the associated branch instruction. When the branch predict instruction is detected, the target address is stored at an entry indicated by the associated branch instruction address and a prefetch request is triggered to the target address. The branch predict instruction may also include hint information for managing the storage and use of the branch prediction information.

Abstract: A load is executed speculatively as a dismissible load instruction, which does not take exceptions, and a check instruction, which is in the same format as the dismissible load, that when executed determines whether an exception should be taken on the dismissible load. In this manner, a load may be executed speculatively while ensuring that an exception occurs at the same time it would have occurred had the load been executed non-speculatively.

Abstract: A processor and method that reduces instruction fetch penalty in the execution of a program sequence of instructions comprises a branch predict instruction that is inserted into the program at a location which precedes the branch. The branch predict instruction has an opcode that specifies a branch as likely to be taken or not taken, and which also specifies a target address of the branch. A block of target instructions, starting at the target address, is prefetched into the instruction cache of the processor so that the instructions are available for execution prior to the point in the program where the branch is encountered. Also specified by the opcode is an indication of the size of the block of target instructions, and a trace vector of a path in the program sequence that leads to the target from the branch predict instruction for better utilization of limited memory bandwidth.

Abstract: A processor microarchitecture for efficient dynamic instruction scheduling and execution. The invention includes a predetermined number of independent dispatch queues. The invention also includes a cluster of execution units coupled to each dispatch queue such that the dispatch queue and the corresponding cluster of execution units forms an independent micropipeline. Chain-building and steering logic coupled to the dispatch queues identifies a consumer instruction relying on a producer instruction for an operand, and issues the consumer instruction to the same dispatch queue as the producer instruction that it is dependent upon. The instructions are issued from the dispatch queue to the corresponding cluster of execution units. In one embodiment, the output of each execution unit in the cluster is routed to the inputs of all execution units in the cluster such that the result of executing the producer instruction is readily available as an operand for execution of the consumer instruction.