Abstract: Technical solutions are described for hazard detection of out-of-order execution of load and store instructions without using real addresses in a processing unit. An example includes an out-of-order load-store unit (LSU) for transferring data between memory and registers. The LSU detects a store-hit-load (SHL) in an out-of-order execution of instructions based only on effective addresses by: determining an effective address associated with a store instruction; determining whether a load instruction entry using said effective address is present in a load reorder queue; and indicating that a SHL has been detected based at least in part on determining that load instruction entry using said effective address is present in the load reorder queue. The LSU, in response to detecting the SHL, flushes instructions starting from a load instruction corresponding to the load instruction entry.

Abstract: Technical solutions are described for issuing, by a load-store unit (LSU), a plurality of instructions from an out-of-order (OoO) window. The issuing includes, in response to determining a first effective address being used by a first instruction, the first effective address corresponding to a first real address, creating an effective real table (ERT) entry in an ERT, the ERT entry mapping the first effective address to the first real address. Further, the execution includes in response to determining an effective address synonym used by a second instruction, the effective address synonym being a second effective address that is also corresponding to said first real address: creating a synonym detection table (SDT) entry in an SDT, wherein the SDT entry maps the second effective address to the ERT entry, and relaunching the second instruction by replacing the second effective address in the second instruction with the first effective address.

Abstract: A computer system, processor, and method for processing information is disclosed that includes determining whether an instruction is a designated instruction, determining whether an instruction following the designated instruction is a subsequent store instruction, speculatively releasing the subsequent store instruction while the designated instruction is pending and before the subsequent store instruction is complete. Preferably, in response to determining that an instruction is the designated instruction, initiating or advancing a speculative tail pointer in an instruction completion table (ICT) to look through the instructions in the ICT following the designated instruction.

Abstract: A computer system, processor, and method for processing information is disclosed that includes a Dispatch Unit for dispatching instructions; an Issue Queue for receiving instructions dispatched from the Dispatch Unit; and a queue for receiving instructions issued from the Issue Queue, the queue having a plurality of entry locations for storing data. In an embodiment instructions are dispatched with a virtual indicator, and the virtual indicator is set to a first mode for instructions dispatched where an entry location is available, and to a second mode where an entry location is not available, in the queue to receive the dispatched instruction. In addition to virtual tagging dispatched instructions, a system, processor, and method are disclosed for regional partitioning of queues, region based deallocation of queue entries, and circular thread based assignment of queue entries.

Abstract: Technical solutions are described for out-of-order (OoO) execution of one or more instructions by a processing unit includes receiving, by a load-store unit (LSU) of the processing unit, an OoO window of instructions including a plurality of instructions to be executed OoO, and issuing, by the LSU, instructions from the OoO window. The issuing includes selecting an instruction from the OoO window, the instruction using an effective address. Further, in response to the instruction being a load instruction, it is determined whether the effective address is present in an effective address directory (EAD). In response to the effective address being present in the EAD, the load instruction is issued using the effective address. Further, in response to the instruction being a store instruction, a real address mapped to the effective address is determined from an effective-real translation (ERT) table, and the store instruction is issued using the real address.

Abstract: A system and method of stopping program execution includes tagging an entry in a virtual cache with an indicator bit where the virtual address of the entry corresponds to a virtual address range in a break point register, in response to a second virtual cache data access demand matching the entry tagged with the indicator bit, determining whether the second data access demand matches the virtual address range of the breakpoint register, and in response to the second data access demand matching the virtual address range of the break point register, flagging an exception and stopping execution of the program. In an embodiment, the method or system enters a slow-mode in response to the second data access demand matching the virtual cache entry with the indicator bit, and performs a full comparison between the second data access demand and the break point register virtual address range.

Abstract: A system and method of handling access demands in a virtual cache comprising, by a processing system, checking if a virtual cache access demand missed because of a synonym tagged in the virtual cache; in response to the virtual cache access demand missing because of a synonym tagged in the virtual cache, updating the virtual address tag in the virtual cache to a new virtual address tag; searching for additional synonyms tagged in the virtual cache; and in response to finding additional synonyms tagged in the virtual cache, updating the virtual address tag of the additional synonyms to the new virtual address tag.

Abstract: A system and method of handling data access demands in a processor virtual cache that includes: determining if a virtual cache data access demand missed because of a difference in the context tag of the data access demand and a corresponding entry in the virtual cache with the same virtual address as the data access demand; in response to the virtual cache missing, determining whether the alias tag valid bit is set in the corresponding entry of the virtual cache; in response to the alias tag valid bit not being set, determining whether the virtual cache data access demand is a synonym of the corresponding entry in the virtual cache; and in response to the virtual access demand being a synonym of the corresponding entry in the virtual cache with the same virtual address but a different context tag, updating information in a tagged entry in an alias table.

Abstract: A computer system, processor, and method for processing information is disclosed that includes determining whether an instruction is a designated instruction, determining whether an instruction following the designated instruction is a subsequent store instruction, speculatively releasing the subsequent store instruction while the designated instruction is pending and before the subsequent store instruction is complete. Preferably, in response to determining that an instruction is the designated instruction, initiating or advancing a speculative tail pointer in an instruction completion table (ICT) to look through the instructions in the ICT following the designated instruction.

Abstract: Technical solutions are described for issuing, by a load-store unit (LSU), a plurality of instructions from an out-of-order (OoO) window. The issuing includes, in response to determining a first effective address being used by a first instruction, the first effective address corresponding to a first real address, creating an effective real table (ERT) entry in an ERT, the ERT entry mapping the first effective address to the first real address. Further, the execution includes in response to determining an effective address synonym used by a second instruction, the effective address synonym being a second effective address that is also corresponding to said first real address: creating a synonym detection table (SDT) entry in an SDT, wherein the SDT entry maps the second effective address to the ERT entry, and relaunching the second instruction by replacing the second effective address in the second instruction with the first effective address.

Abstract: Embodiments of the present invention include methods, systems, and computer program products for allocating and deallocating reorder queue entries for an out-of-order (OoO) processor. An example method includes dividing the reorder queue into a plurality of regions to store reorder queue entries; allocating a plurality of reorder queue entries into an instruction tag array for tracking the reorder queue entries based at least in part on an associated instruction tag; loading instruction tags into each region of the plurality of regions beginning with a first region of the plurality of regions, wherein a first plurality of instruction tags is loaded into the first region; deallocating all of the first plurality of instruction tags of the first region; and subsequent to all of the instruction tags of the first region being deallocated, loading a second plurality of instruction tags to the first region of the plurality of regions.

Abstract: Technical solutions are described for out-of-order (OoO) execution of one or more instructions by a processing unit includes receiving, by a load-store unit (LSU) of the processing unit, an OoO window of instructions including a plurality of instructions to be executed OoO, and issuing, by the LSU, instructions from the OoO window. The issuing includes selecting an instruction from the OoO window, the instruction using an effective address. Further, in response to the instruction being a load instruction, it is determined whether the effective address is present in an effective address directory (EAD). In response to the effective address being present in the EAD, the load instruction is issued using the effective address. Further, in response to the instruction being a store instruction, a real address mapped to the effective address is determined from an effective-real translation (ERT) table, and the store instruction is issued using the real address.

Abstract: Technical solutions are described for issuing, by a load-store unit (LSU), a plurality of instructions from an out-of-order (OoO) window. The issuing includes, in response to determining a first effective address being used by a first instruction, the first effective address corresponding to a first real address, creating an effective real table (ERT) entry in an ERT, the ERT entry mapping the first effective address to the first real address. Further, the execution includes in response to determining an effective address synonym used by a second instruction, the effective address synonym being a second effective address that is also corresponding to said first real address: creating a synonym detection table (SDT) entry in an SDT, wherein the SDT entry maps the second effective address to the ERT entry, and relaunching the second instruction by replacing the second effective address in the second instruction with the first effective address.

Abstract: Technical solutions are described for out-of-order (OoO) execution of one or more instructions by a processing unit. An example method includes looking up, by a load-store unit (LSU), an entry in an effective address directory (EAD) for an effective address (EA) of an operand of an instruction to be launched. Further, the method includes, in response to the EA being present in the EAD, launching, by the LSU, the instruction with the RA from the EAD, and in response to the EA not being present in the EAD, looking up, by the LSU, the EA in an effective real table (ERT) entry, and launching the instruction with the RA from the ERT entry. Further, in response to the ERT entry to be removed, the ERT entry including an ERT index and a mapping between the EA and the RA, removing the entry of the EA from the EAD.

Abstract: Technical solutions are described for issuing, by a load-store unit (LSU), a plurality of instructions from an out-of-order (OoO) window. The issuing includes, in response to determining a first effective address being used by a first instruction, the first effective address corresponding to a first real address, creating an effective real table (ERT) entry in an ERT, the ERT entry mapping the first effective address to the first real address. Further, the execution includes in response to determining an effective address synonym used by a second instruction, the effective address synonym being a second effective address that is also corresponding to said first real address: creating a synonym detection table (SDT) entry in an SDT, wherein the SDT entry maps the second effective address to the ERT entry, and relaunching the second instruction by replacing the second effective address in the second instruction with the first effective address.

Abstract: Technical solutions are described for out-of-order (OoO) execution of one or more instructions by a processing unit. An example method includes looking up, by a load-store unit (LSU), an entry in an effective address directory (EAD) for an effective address (EA) of an operand of an instruction to be launched. Further, the method includes, in response to the EA being present in the EAD, launching, by the LSU, the instruction with the RA from the EAD, and in response to the EA not being present in the EAD, looking up, by the LSU, the EA in an effective real table (ERT) entry, and launching the instruction with the RA from the ERT entry. Further, in response to the ERT entry to be removed, the ERT entry including an ERT index and a mapping between the EA and the RA, removing the entry of the EA from the EAD.

Abstract: Technical solutions are described for executing one or more out-of-order (OoO) instructions by a processing unit. The execution includes detecting, by a load-store unit (LSU), a load-hit-store (LHS) in an out-of-order execution of the instructions, the detecting based only on effective addresses. The detecting includes determining an effective address associated with an operand of a load instruction. The detecting further includes determining whether a store instruction entry using said effective address to store a data value is present in a store reorder queue, and indicating that an LHS has been detected based at least in part on determining that store instruction entry using said effective address is present in the store reorder queue. In response to detecting the LHS, a store forwarding is performed that includes forwarding data from the store instruction to the load instruction.

Abstract: Technical solutions are described for issuing, by a load-store unit (LSU), a plurality of instructions from an out-of-order (OoO) window. The issuing includes, in response to determining a first effective address (EA) being used by a first instruction, the first EA corresponding to a first real address (RA), creating a first effective real translation (ERT) table entry in an ERT table, the ERT entry mapping the first EA to the first RA. Further, in response to determining an EA synonym used by a second instruction, the execution includes replacing the first ERT entry with a second ERT entry, wherein the second ERT entry maps the second EA with the first RA, and creating an ERT eviction (ERTE) table entry in an ERTE table, wherein the ERTE entry maps the first RA to the first EA, the ERTE table entry maintains the relationship between the first EA and the first RA.

Abstract: Technical solutions are described for issuing, by a load-store unit (LSU), a plurality of instructions from an out-of-order (OoO) window. The issuing includes, in response to determining a first effective address (EA) being used by a first instruction, the first EA corresponding to a first real address (RA), creating a first effective real translation (ERT) table entry in an ERT table, the ERT entry mapping the first EA to the first RA. Further, in response to determining an EA synonym used by a second instruction, the execution includes replacing the first ERT entry with a second ERT entry, wherein the second ERT entry maps the second EA with the first RA, and creating an ERT eviction (ERTE) table entry in an ERTE table, wherein the ERTE entry maps the first RA to the first EA, the ERTE table entry maintains the relationship between the first EA and the first RA.

Abstract: A computer system, processor, and method for processing information is disclosed that includes a Dispatch Unit for dispatching instructions; an Issue Queue for receiving instructions dispatched from the Dispatch Unit; and a queue for receiving instructions issued from the Issue Queue, the queue having a plurality of entry locations for storing data. In an embodiment instructions are dispatched with a virtual indicator, and the virtual indicator is set to a first mode for instructions dispatched where an entry location is available, and to a second mode where an entry location is not available, in the queue to receive the dispatched instruction. In addition to virtual tagging dispatched instructions, a system, processor, and method are disclosed for regional partitioning of queues, region based deallocation of queue entries, and circular thread based assignment of queue entries.