摘要:
An adaptive prediction threshold scheme for dynamically adjusting prediction thresholds of entries in a Pattern History Table (PHT) by observing global tendencies of the branch or branches that index into the PHT entries. A count value of a prediction state counter representing a prediction state of a prediction state machine for a PHT entry is obtained. Count values in a set of counters allocated to the entry in the PHT are changed based on the count value of the entry's prediction state counter. The prediction threshold of the prediction state machine for the entry may then be adjusted based on the changed count values in the set of counters, wherein the prediction threshold is adjusted by changing a count value in a prediction threshold counter in the entry, and wherein adjusting the prediction threshold redefines predictions provided by the prediction state machine.
摘要:
Systems, apparatuses, and methods for improving TM throughput using a TM region indicator (or color) are described. Through the use of TM region indicators younger TM regions can have their instructions retired while waiting for older TM regions to commit.
摘要:
A method of memory disambiguation hardware to support software binary translation is provided. This method includes unrolling a set of instructions to be executed within a processor, the set of instructions having a number of memory operations. An original relative order of memory operations is determined. Then, possible reordering problems are detected and identified in software. The reordering problem being when a first memory operation has been reordered prior to and aliases to a second memory operation with respect to the original order of memory operations. The reordering problem is addressed and a relative order of memory operations to the processor is communicated.
摘要:
A hardware profiling mechanism implemented by performance monitoring hardware enables page level automatic binary translation. The hardware during runtime identifies a code page in memory containing potentially optimizable instructions. The hardware requests allocation of a new page in memory associated with the code page, where the new page contains a collection of counters and each of the counters corresponds to one of the instructions in the code page. When the hardware detects a branch instruction having a branch target within the code page, it increments one of the counters that has the same position in the new page as the branch target in the code page. The execution of the code page is repeated and the counters are incremented when branch targets fall within the code page. The hardware then provides the counter values in the new page to a binary translator for binary translation.
摘要:
Systems, apparatuses, and methods for improving TM throughput using a TM region indicator (or color) are described. Through the use of TM region indicators younger TM regions can have their instructions retired while waiting for older TM regions to commit.
摘要:
A method of memory disambiguation hardware to support software binary translation is provided. This method includes unrolling a set of instructions to be executed within a processor, the set of instructions having a number of memory operations. An original relative order of memory operations is determined. Then, possible reordering problems are detected and identified in software. The reordering problem being when a first memory operation has been reordered prior to and aliases to a second memory operation with respect to the original order of memory operations. The reordering problem is addressed and a relative order of memory operations to the processor is communicated.
摘要:
A dynamic optimization of code for a processor-specific dynamic binary translation of hot code pages (e.g., frequently executed code pages) may be provided by a run-time translation layer. A method may be provided to use an instruction look-aside buffer (iTLB) to map original code pages and translated code pages. The method may comprise fetching an instruction from an original code page, determining whether the fetched instruction is a first instruction of a new code page and whether the original code page is deprecated. If both determinations return yes, the method may further comprise fetching a next instruction from a translated code page. If either determinations returns no, the method may further comprise decoding the instruction and fetching the next instruction from the original code page.
摘要:
Systems, apparatuses, and methods for improving TM throughput using a TM region indicator (or color) are described. Through the use of TM region indicators younger TM regions can have their instructions retired while waiting for older TM regions to commit.
摘要:
A hardware profiling mechanism implemented by performance monitoring hardware enables page level automatic binary translation. The hardware during runtime identifies a code page in memory containing potentially optimizable instructions. The hardware requests allocation of a new page in memory associated with the code page, where the new page contains a collection of counters and each of the counters corresponds to one of the instructions in the code page. When the hardware detects a branch instruction having a branch target within the code page, it increments one of the counters that has the same position in the new page as the branch target in the code page. The execution of the code page is repeated and the counters are incremented when branch targets fall within the code page. The hardware then provides the counter values in the new page to a binary translator for binary translation.
摘要:
A vector reduction instruction is executed by a processor to provide efficient reduction operations on an array of data elements. The processor includes vector registers. Each vector register is divided into a plurality of lanes, and each lane stores the same number of data elements. The processor also includes execution circuitry that receives the vector reduction instruction to reduce the array of data elements stored in a source operand into a result in a destination operand using a reduction operator. Each of the source operand and the destination operand is one of the vector registers. Responsive to the vector reduction instruction, the execution circuitry applies the reduction operator to two of the data elements in each lane, and shifts one or more remaining data elements when there is at least one of the data elements remaining in each lane.