| Patent application number | Description | Published |
|---|
| 20080215804 | STRUCTURE FOR REGISTER RENAMING IN A MICROPROCESSOR - A design structure embodied in a machine readable storage medium for at least one of designing, manufacturing, and testing a design for register renaming allows processor hardware to use a larger set of registers than the architected registers visible to the compiler. This larger set of registers is called the physical register file. Thus, dynamically renaming every compiler-suggested architected register to a microarchitecture-specific physical register, allows the processor to overcome name dependencies and the hazards (pipeline slowdowns) induced by name dependencies. | 09-04-2008 |
| 20080235500 | STRUCTURE FOR INSTRUCTION CACHE TRACE FORMATION - A design structure embodied in a machine readable storage medium for at least one of designing, manufacturing, and testing a design for a single unified level one instruction cache in which some lines may contain traces and other lines in the same congruence class may contain blocks of instructions consistent with conventional cache lines is provided. Instruction branches are predicted taken or not taken using a highly accurate branch history table (BHT). Branches that are predicted not taken are appended to a trace buffer and the next basic block is constructed from the remaining instructions in the fetch buffer. Branches that are predicted taken flush the remaining fetch buffer and the next address is determined using a Branch Target Address Register (BTAC). | 09-25-2008 |
| 20080250205 | STRUCTURE FOR SUPPORTING SIMULTANEOUS STORAGE OF TRACE AND STANDARD CACHE LINES - A design structure embodied in a machine readable storage medium for designing, manufacturing, and/or testing a design for a single unified level one instruction cache in which some lines may contain traces and other lines in the same congruence class may contain blocks of instructions consistent with conventional cache lines is provided. A mechanism is described for indexing into the cache, and selecting the desired line. Control is exercised over which lines are contained within the cache. Provision is made for selection between a trace line and a conventional line when both match during a tag compare step. | 10-09-2008 |
| 20080250206 | STRUCTURE FOR USING BRANCH PREDICTION HEURISTICS FOR DETERMINATION OF TRACE FORMATION READINESS - A design structure embodied in a machine readable storage medium for designing, manufacturing, and/or testing a design for a single unified level one instruction(s) cache in which some lines may contain traces and other lines in the same congruence class may contain blocks of instruction(s) consistent with conventional cache lines is provided. Formation of trace lines in the cache is delayed on initial operation of the system to assure quality of the trace lines stored. | 10-09-2008 |
| 20080250207 | DESIGN STRUCTURE FOR CACHE MAINTENANCE - A single unified level one instruction cache in which some lines may contain traces and other lines in the same congruence class may contain blocks of instructions consistent with conventional cache lines. Control is exercised over which lines are contained within the cache. This invention avoids inefficiencies in the cache by removing trace lines experiencing early exits from the cache, or trace lines that are short, by maintaining a few bits of information about the accuracy of the control flow in a trace cache line and using that information in addition to the LRU (Least Recently Used) bits that maintain the recency information of a cache line, in order to make a replacement decision. | 10-09-2008 |
| 20090063819 | Method and Apparatus for Dynamically Managing Instruction Buffer Depths for Non-Predicted Branches - A method and apparatus for dynamically managing instruction buffer depths for non-predicted branches reduces wasted energy and resources associated with low confidence branch prediction conditions. A portion of the instruction buffer for a instruction thread is allocated for storing predicted branch instruction streams and another portion, which may be zero-sized during high prediction confidence conditions, is allocated to the non-predicted branch instruction stream. The size of the buffers is adjusted dynamically in conformity with an on-going prediction confidence that provides a measure of how well branch prediction mechanisms are working for a given instruction thread. An alternate instruction fetch address table can be maintained and multiplexed with the main fetch address register for addressing the instruction cache, so that the instruction stream can be quickly shifted to the non-predicted path when a branch instruction is resolved to the non-predicted path. | 03-05-2009 |
| 20090249349 | Power-Efficient Thread Priority Enablement - A mechanism for controlling instruction fetch and dispatch thread priority settings in a thread switch control register for reducing the occurrence of balance flushes and dispatch flushes for increased power performance of a simultaneous multi-threading data processing system. To achieve a target power efficiency mode of a processor, the illustrative embodiments receive an instruction or command from a higher-level system control to set a current power consumption of the processor. The illustrative embodiments determine a target power efficiency mode for the processor. Once the target power mode is determined, the illustrative embodiments update thread priority settings in a thread switch control register for an executing thread to control balance flush speculation and dispatch flush speculation to achieve the target power efficiency mode. | 10-01-2009 |
| 20100262806 | Tracking Effective Addresses in an Out-of-Order Processor - Mechanisms, in a data processing system, are provided for tracking effective addresses through a processor pipeline of the data processing system. The mechanisms comprise logic for fetching an instruction from an instruction cache and associating, by an effective address table logic in the data processing system, an entry in an effective address table (EAT) data structure with the fetched instruction. The mechanisms further comprise logic for associating an effective address tag (eatag) with the fetched instruction, the eatag comprising a base eatag that points to the entry in the EAT and an eatag offset. Moreover, the mechanisms comprise logic for processing the instruction through the processor pipeline by processing the eatag. | 10-14-2010 |
| 20100262813 | Detecting and Handling Short Forward Branch Conversion Candidates - Mechanisms, in a processor, are provided for detecting and handling short forward branch conversion candidates. The mechanisms identify a conditional branch in the computer code and determine if the short forward conditional branch is to be converted to a non-branching conditional sequence of instructions. Moreover, the mechanisms convert the conditional branch to a non-branching conditional sequence of instructions comprising a resolve instruction and one or more conditional instructions dependent on the resolve instruction. In addition, the mechanisms execute the non-branching conditional sequence of instructions in place of the conditional branch in the computer code and generate an output of the computer code based on the execution of the non-branching conditional sequence of instructions. | 10-14-2010 |
| 20110131394 | APPARATUS AND METHOD FOR USING BRANCH PREDICTION HEURISTICS FOR DETERMINATION OF TRACE FORMATION READINESS - A single unified level one instruction(s) cache in which some lines may contain traces and other lines in the same congruence class may contain blocks of instruction(s) consistent with conventional cache lines. Formation of trace lines in the cache is delayed on initial operation of the system to assure quality of the trace lines stored. | 06-02-2011 |
