Abstract: Embodiments include load-balancing a plurality of simultaneous threads of a processor. An example method includes computing a minimum group count for a thread from the plurality of threads. The minimum group count indicates a minimum number of groups of instructions to be assigned to the thread. The method further includes computing a maximum allowed group count for the thread. The maximum allowed group count indicates a maximum number of groups of instructions to be assigned to the thread. The method further includes issuing one or more groups of instructions for execution by the thread based on the minimum group count and the maximum allowed group count for the thread.

Abstract: Embodiments of the present invention provide a system for balancing a global completion table (GCT) in a microprocessor via frontend steering or stalls. A non-limiting example of the system includes an instruction dispatch unit (IDU) that includes an instruction queue and the system includes an instruction sequencing unit (ISU) that includes a GCT having a first area and a second area. The IDU is configured to determine whether a full group of instructions exist in the instruction queue and to determine whether additional instructions will be received by the instruction queue in a subsequent cycle. The IDU is configured to stall the instruction queue for at least one cycle until a full group of instructions is accumulated at the instruction queue upon determining that additional instructions will be received by the instruction queue in subsequent cycle.

Abstract: Embodiments include load-balancing a plurality of simultaneous threads of a processor. An example method includes computing a minimum group count for a thread from the plurality of threads. The minimum group count indicates a minimum number of groups of instructions to be assigned to the thread. The method further includes computing a maximum allowed group count for the thread. The maximum allowed group count indicates a maximum number of groups of instructions to be assigned to the thread. The method further includes issuing one or more groups of instructions for execution by the thread based on the minimum group count and the maximum allowed group count for the thread.

Abstract: Embodiments include load-balancing a plurality of simultaneous threads of a processor. An example method includes computing a minimum group count for a thread from the plurality of threads. The minimum group count indicates a minimum number of groups of instructions to be assigned to the thread. The method further includes computing a maximum allowed group count for the thread. The maximum allowed group count indicates a maximum number of groups of instructions to be assigned to the thread. The method further includes issuing one or more groups of instructions for execution by the thread based on the minimum group count and the maximum allowed group count for the thread.

Abstract: As disclosed herein a method, executed by a processor, for accelerated instruction execution includes retrieving an execute instruction including a register reference and a reference to a target instruction, retrieving the target instruction, decoding the execute instruction using an instruction pipeline, decoding the target instruction using the instruction pipeline, associating the register reference to the target instruction, and executing the target instruction using the register reference as a source operand modifier. The instruction pipeline is configured such that it allows the target instruction to continue processing without waiting for the register reference to be resolved. The contents of the referenced register may be retrieved in a later stage of the instruction pipeline, and the target instruction may be modified and executed. An apparatus corresponding to the described method is also disclosed herein.

Abstract: Embodiments of the invention are directed to methods for handling scratch registers in a processor. The method includes receiving a cracked instruction in an instruction dispatch unit of the processor. The method further includes decoding the cracked instruction into a group of micro-operations. Based on a determination that the instruction group uses a scratch register, determining if the scratch register is used in other groups of micro-operations. Based on a determination that the scratch register is not used in other instruction groups, allocating a physical register for use as the scratch register without creating a mapper entry for the scratch register.

Abstract: Embodiments of the invention are directed to methods for handling scratch registers in a processor. The method includes receiving a cracked instruction in an instruction dispatch unit of the processor. The method further includes decoding the cracked instruction into a group of micro-operations. Based on a determination that the instruction group uses a scratch register, determining if the scratch register is used in other groups of micro-operations. Based on a determination that the scratch register is not used in other instruction groups, allocating a physical register for use as the scratch register without creating a mapper entry for the scratch register.

Abstract: Embodiments of the present invention provide a system for balancing a global completion table (GCT) in a microprocessor via frontend steering or stalls. A non-limiting example of the system includes an instruction dispatch unit (IDU) that includes an instruction queue and the system includes an instruction sequencing unit (ISU) that includes a GCT having a first area and a second area. The IDU is configured to determine whether a full group of instructions exist in the instruction queue and to determine whether additional instructions will be received by the instruction queue in a subsequent cycle. The IDU is configured to stall the instruction queue for at least one cycle until a full group of instructions is accumulated at the instruction queue upon determining that additional instructions will be received by the instruction queue in subsequent cycle.

Abstract: Embodiments include load-balancing a plurality of simultaneous threads of a processor. An example method includes computing a minimum group count for a thread from the plurality of threads. The minimum group count indicates a minimum number of groups of instructions to be assigned to the thread. The method further includes computing a maximum allowed group count for the thread. The maximum allowed group count indicates a maximum number of groups of instructions to be assigned to the thread. The method further includes issuing one or more groups of instructions for execution by the thread based on the minimum group count and the maximum allowed group count for the thread.

Abstract: As disclosed herein a method, executed by a processor, for accelerated instruction execution includes retrieving an execute instruction including a register reference and a reference to a target instruction, retrieving the target instruction, decoding the execute instruction using an instruction pipeline, decoding the target instruction using the instruction pipeline, associating the register reference to the target instruction, and executing the target instruction using the register reference as a source operand modifier. The instruction pipeline is configured such that it allows the target instruction to continue processing without waiting for the register reference to be resolved. The contents of the referenced register may be retrieved in a later stage of the instruction pipeline, and the target instruction may be modified and executed. An apparatus corresponding to the described method is also disclosed herein.

Abstract: As disclosed herein a method, executed by a processor, for accelerated instruction execution includes retrieving an execute instruction including a register reference and a reference to a target instruction, retrieving the target instruction, decoding the execute instruction using an instruction pipeline, decoding the target instruction using the instruction pipeline, associating the register reference to the target instruction, and executing the target instruction using the register reference as a source operand modifier. The instruction pipeline is configured such that it allows the target instruction to continue processing without waiting for the register reference to be resolved. The contents of the referenced register may be retrieved in a later stage of the instruction pipeline, and the target instruction may be modified and executed. An apparatus corresponding to the described method is also disclosed herein.

Abstract: Embodiments include optimizing the grouping of instructions in a microprocessor. Aspects include receiving a first clump of instructions from a streaming buffer, pre-decoding each of instructions for select information and sending the instructions to an instruction queue. Aspects further include storing initial grouping information for the instructions in a local register, wherein the initial grouping information is based on the select information. Aspects further include updating the initial group information stored in the local register when additional pre-decode information becomes available and grouping the instructions that are ready to be dispatched into a dispatch group based on the grouping information stored in the local register. Aspects further include dispatching the dispatch group to an issue unit.

Abstract: Embodiments include optimizing the grouping of instructions in a microprocessor. Aspects include receiving a first clump of instructions from a streaming buffer, pre-decoding each of instructions for select information and sending the instructions to an instruction queue. Aspects further include storing initial grouping information for the instructions in a local register, wherein the initial grouping information is based on the select information. Aspects further include updating the initial group information stored in the local register when additional pre-decode information becomes available and grouping the instructions that are ready to be dispatched into a dispatch group based on the grouping information stored in the local register. Aspects further include dispatching the dispatch group to an issue unit.

Abstract: As disclosed herein a method, executed by a processor, for accelerated instruction execution includes retrieving an execute instruction including a register reference and a reference to a target instruction, retrieving the target instruction, decoding the execute instruction using an instruction pipeline, decoding the target instruction using the instruction pipeline, associating the register reference to the target instruction, and executing the target instruction using the register reference as a source operand modifier. The instruction pipeline is configured such that it allows the target instruction to continue processing without waiting for the register reference to be resolved. The contents of the referenced register may be retrieved in a later stage of the instruction pipeline, and the target instruction may be modified and executed. An apparatus corresponding to the described method is also disclosed herein.

Abstract: As disclosed herein a method, executed by a processor, for accelerated instruction execution includes retrieving an execute instruction including a register reference and a reference to a target instruction, retrieving the target instruction, decoding the execute instruction using an instruction pipeline, decoding the target instruction using the instruction pipeline, associating the register reference to the target instruction, and executing the target instruction using the register reference as a source operand modifier. The instruction pipeline is configured such that it allows the target instruction to continue processing without waiting for the register reference to be resolved. The contents of the referenced register may be retrieved in a later stage of the instruction pipeline, and the target instruction may be modified and executed. An apparatus corresponding to the described method is also disclosed herein.

Abstract: As disclosed herein a method, executed by a processor, for accelerated instruction execution includes retrieving an execute instruction including a register reference and a reference to a target instruction, retrieving the target instruction, decoding the execute instruction using an instruction pipeline, decoding the target instruction using the instruction pipeline, associating the register reference to the target instruction, and executing the target instruction using the register reference as a source operand modifier. The instruction pipeline is configured such that it allows the target instruction to continue processing without waiting for the register reference to be resolved. The contents of the referenced register may be retrieved in a later stage of the instruction pipeline, and the target instruction may be modified and executed. An apparatus corresponding to the described method is also disclosed herein.

Abstract: Embodiments include optimizing the grouping of instructions in a microprocessor. Aspects include receiving a first clump of instructions from a streaming buffer, pre-decoding each of instructions for select information and sending the instructions to an instruction queue. Aspects further include storing initial grouping information for the instructions in a local register, wherein the initial grouping information is based on the select information. Aspects further include updating the initial group information stored in the local register when additional pre-decode information becomes available and grouping the instructions that are ready to be dispatched into a dispatch group based on the grouping information stored in the local register. Aspects further include dispatching the dispatch group to an issue unit.

Abstract: Embodiments include optimizing the grouping of instructions in a microprocessor. Aspects include receiving a first clump of instructions from a streaming buffer, pre-decoding each of instructions for select information and sending the instructions to an instruction queue. Aspects further include storing initial grouping information for the instructions in a local register, wherein the initial grouping information is based on the select information. Aspects further include updating the initial group information stored in the local register when additional pre-decode information becomes available and grouping the instructions that are ready to be dispatched into a dispatch group based on the grouping information stored in the local register. Aspects further include dispatching the dispatch group to an issue unit.

Abstract: Embodiments relate to mitigation of lookahead branch predication latency. An aspect includes receiving an instruction address in an instruction cache for fetching instructions in a microprocessor pipeline. Another aspect includes receiving the instruction address in a branch presence predictor coupled to the microprocessor pipeline. Another aspect includes determining, by the branch presence predictor, presence of a branch instruction in the instructions being fetched, wherein the branch instruction is predictable by the branch target buffer, and any indication of the instruction address not written to the branch target buffer is also not written to the branch presence predictor. Another aspect includes, based on receipt of an indication that the branch instruction is present from the branch presence predictor, holding the branch instruction.

Abstract: The exemplary embodiment of the present invention relates to a generalized LRU algorithm is provided that is associated with a specified cache associativity line set value that is determined by a system user. As configured, the LRU algorithm as presented can comprise n-levels for an LRU tree, each specified tree being individually analyzed within the LRU algorithm. Within each LRU tree level comprises the associativity line value can be further broken down into sub-analysis groups of any desired configuration, however, the total sub-analysis group configuration must equal the specified cache associativity line value.