Abstract:
An apparatus and method are described for non-speculative execution of conditional instructions. For example, one embodiment of a processor comprises: a register set including a first register to store a set of one or more condition bits; non-speculative execution logic to execute a first instruction to identify a first target instruction strand in response to a first conditional value read from the set of condition bits, the first instruction to wait until the first conditional value becomes known before causing the first target instruction strand to be fetched and executed, the non-speculative execution logic to execute a second instruction to identify an end of the first target instruction strand and responsively identify a new current instruction pointer for instructions which follow the second instruction; and out-of-order execution logic to fetch and execute the instructions which follow the second instruction prior to the execution of the second instruction.
Abstract:
Embodiments of systems, apparatuses, and methods for performing gather and scatter stride instruction in a computer processor are described. In some embodiments, the execution of a gather stride instruction causes a conditionally storage of strided data elements from memory into the destination register according to at least some of bit values of a writemask.
Abstract:
An apparatus and method are described for performing efficient gather operations in a pipelined processor. For example, a processor according to one embodiment of the invention comprises: gather setup logic to execute one or more gather setup operations in anticipation of one or more gather operations, the gather setup operations to determine one or more addresses of vector data elements to be gathered by the gather operations; and gather logic to execute the one or more gather operations to gather the vector data elements using the one or more addresses determined by the gather setup operations.
Abstract:
A method for processing registers in an out-of-order processor. A predicate in an instruction is predicted. An architecturally correct value is then computed using a read-modify-write operation. The predicted value is compared to the architecturally correct value. The instruction with an incorrectly-predicted predicate is flushed from the pipeline if the predicted value and the architecturally correct value are different.
Abstract:
A processor includes a digital throttle to monitor the activity of various units of the processor's instruction execution pipeline. The monitored activity is scaled according to the current operating point of the processor and a power state is determined from the scaled activity. If the power state reaches a first threshold, the operating point of the processor is adjusted and a new scaling factor is selected to determine the power state.
Abstract:
The invention, in one embodiment, is a method for committing the results of at least two speculatively executed instructions to an architectural state in a superscalar processor. The method includes determining which of the speculatively executed instructions encountered a problem in execution, and replaying the instruction that encountered the problem in execution while retaining the results of executing the instruction that did not encounter the problem.
Abstract:
Disclosed are an apparatus, system, and method for implementing predicated instructions using micro-operations. A micro-code engine receives an instruction, decomposes the instruction, and generates a plurality of micro-operations to implement the instruction. Each of the decomposed micro-operations indicates a single destination register. For predicated instructions, the decomposed micro-operations include “conditional move” micro-operations to select between two potential output values. Except in the case that one of the potential output values is a constant, the decomposed micro-operations for a predicated instruction also include an append instruction that saves the incoming value of a destination register in a temporary variable. For at least one embodiment, the qualifying predicate for a predicated instruction is appended to the incoming value stored in the temporary register.
Abstract:
In an embodiment, a processor includes: a plurality of first cores to independently execute instructions, each of the plurality of first cores including a plurality of counters to store performance information; at least one second core to perform memory operations; and a power controller to receive performance information from at least some of the plurality of counters, determine a workload type executed on the processor based at least in part on the performance information, and based on the workload type dynamically migrate one or more threads from one or more of the plurality of first cores to the at least one second core for execution during a next operation interval. Other embodiments are described and claimed.
Abstract:
In one embodiment, a method includes receiving an instruction for decoding in a processor core and dynamically handling the instruction with one of multiple behaviors based on whether contention is predicted. If no contention is predicted, the instruction is executed in the core, and if contention is predicted data associated with the instruction is marshaled and sent to a selected remote agent for execution. Other embodiments are described and claimed.
Abstract:
An instruction prefetch apparatus includes a branch target buffer (BTB), a presbyopic target buffer (PTB) and a prefetch stream buffer (PSB). The BTB includes records that map branch addresses to branch target addresses, and the PTB includes records that map branch target addresses to subsequent branch target addresses. When a branch instruction is encountered, the BTB can predict the dynamically adjacent subsequent block entry location as the branch target address in the record that also includes the branch instruction address. The PTB can predict multiple subsequent blocks by mapping the branch target address to subsequent dynamic blocks. The PSB holds instructions prefetched from subsequent blocks predicted by the PTB.