International Business Machines Corporation

Advanced Micro Devices Corporation

Salim Ahmed Shah

Dung Q Nguyen

Jeffrey Carl Brownscheidle

Sundeep Chadha

Brian William Thompto

Salma Ayub

Dhivya Jeganathan

Visweswara Rao Kodali

Joshua W Bowman

Tu-An T Nguyen

Maureen Anne Delaney

Thomas W Lynch

Brian David Barrick

Christopher McCall Durham

Paul Gerard Villarrubia

Peichun Peter Liu

Shyam Ramji

Kurt Alan Feiste

Michael Joseph Genden

Johnny James LeBlanc

Rajinder Paul Singh

Tony Hurson

Rokesh Jayasundar

Aquilur Rahman

Kevin William McCauley

Howard Lawrence Levy

Akif A Ali

Stephen D McIntyre

Ken Tseng

Fast issuance and execution of a multi-width instruction across multiple slices in a parallel slice processor core is supported in part through the use of an early notification signal passed between issue logic associated with multiple slices handling that multi-width instruction coupled with an issuance of a different instruction by the originating issue logic for the early notification signal.

Fast multi-width instruction issue in parallel slice processor

A design system accesses at least one placement template for at least one structured soft block composed of a pre-defined set of cells with relative placement information for the pre-defined set of cells. The design system optimizes implementation of the at least one structured soft block by propagating constants while preserving relative placement structure of the pre-defined set of cells within each at least one structured soft block according to the respective at least one placement template accessed for the at least one structured soft block.

Propagating constants of structured soft blocks while preserving the relative placement structure

Operation of a multi-slice processor that includes a plurality of execution slices and an instruction sequencing unit. Operation of such a multi-slice processor includes: receiving, at the instruction sequencing unit, a load instruction indicating load address data and a load data length; determining a previous store instruction in an issue queue such that store address data for the previous store instruction corresponds to the load address data, wherein the previous store instruction corresponds to a store data length; and generating, in dependence upon the store data length matching the load data length, an indication in the issue queue that indicates a dependency between the load instruction and the previous store instruction.

Operation of a multi-slice processor implementing load-hit-store handling

Embodiments herein describe a reservation station (RS) in a processor that merges control data from multiple sources into a merged control data value. Before an instruction issues, the RS gathers and saves control data indicating how the instruction is to be executed. This control data may be saved in control registers. An instruction, however, can update many different types of status control bits in these registers. As such, the RS may store different types of control data for an instruction. Instead of the RS containing multiple registers and data paths for every type of control data, the embodiments herein describe merge logic in the RS that permits control data from different sources to be merged into a single control data value. Once the instruction is issued, the RS passes the merged control data value to an execution unit for processing.

Merging status and control data in a reservation station

Methods and apparatus for transmitting data between execution slices of a multi-slice processor including receiving, by an execution slice, a broadcast message comprising an instruction tag (ITAG) for a producer instruction, a latency, and a source identifier; determining that an issue queue in the execution slice comprises an ITAG for a consumer instruction, wherein the consumer instruction depends on result data from the producer instruction; calculating a cycle countdown using the latency and the source identifier; determining that the cycle countdown has expired; and in response to determining that the cycle countdown has expired, reading the result data from the producer instruction.

Broadcasting messages between execution slices for issued instructions indicating when execution results are ready

Operation of a multi-slice processor that includes execution slices and a dispatch network of the multi-slice processor implementing a hardware level mechanism to overcome a system hang. Such a multi-slice processor includes a plurality of execution slices and a dispatch network of the multi-slice processor implementing a hardware level mechanism to overcome a system hang. Operation of such a multi-slice processor includes, storing, in one or more logical units of a plurality of logical units of an age array, a logical value representing a relative age between instructions; propagating, in response to a current instruction being in a hang state, a hang signal to the plurality of logical units of the age array; in response to the hang signal, generating, from the plurality of logical units, a plurality of logical output values indicating a next instruction ready for execution; and issuing the next instruction for execution.

Operation of a multi-slice processor implementing a mechanism to overcome a system hang

Operation of a multi-slice processor that includes execution slices implementing dynamic switching of instruction issuance order. Such a multi-slice processor includes determining a current issuance order for a plurality of instructions and a change in an operating condition of the multi-slice processor; responsive to determining the change in the operating condition, determining an alternate issuance order for the plurality of instructions; and responsive to determining the alternate issuance order, switching from the current issuance order for the plurality of instructions to the alternate issuance order for the plurality of instructions.

Operation of a multi-slice processor implementing dynamic switching of instruction issuance order

A circuit for identifying one or more bit positions of instances of a selected bit value in an N-bit input bit string includes a plurality of adders that compute, in parallel, sums of bits in each of P input substrings comprising the input bit string. A plurality of zero position detectors detect, for each of the P input substrings for which a corresponding sum differs from a threshold sum, one or more bit positions of the selected bit value. Correction logic generates adjustment indications indicative of a number of detected instances of the selected bit value. A plurality of output substring adjusters that, based on the detected bit positions and the adjustment indications, collectively output one or more output vectors identifying a bit position of at least an Mth instance of the selected bit value in the input bit string.

Identification of the bit position of a selected instance of a particular bit value in a binary bit string

A method and implementing system is provided in which input signal specifications, element internal delays and output loads, for each element in a circuit design, are utilized in an iterative processing engine to objectively determine and provide a timing rule database for a circuit being designed. A schematic database netlist is run through a test model converter program to provide a test model database at a gate level for the test model design circuit. These data are processed by a designer through a workstation GUI and the result is applied to an I/O design testing function. The results of the I/O design testing function include a listing of patterns of input combinations which are needed to get listed outputs. The GUI prepares a sequence of stimuli to test the circuit with a timing simulator. Based on the output response of the timing simulator, delay relationships under various input and output load conditions are compiled.

Analyzing CMOS circuit delay

A cache sub-array arbitration circuit for receiving a plurality of address operands from a pending line of processor instructions in order to pre-fetch data needed in any memory access request in the pending instructions. The sub-array arbitration circuit compares at least two addresses corresponding to memory locations in the cache, and determines in which sub-arrays the memory locations reside. If the two memory locations reside in the same sub-array, the arbitration circuit sends the higher priority address to the sub-array. If a received address operand is the real address of a cache miss, the arbitration circuit sends the cache miss address to the sub-array before other pre-fetch memory access request.

Cache sub-array arbitration

According to the present invention, a domino CMOS logic circuit having a plurality of stages for evaluating logic signals is provided. In one embodiment, the domino CMOS logic circuit includes at least one stage which has a logic block that includes a plurality of logic devices, inputs and outputs, and a precharge/evaluate circuit. In a more specific embodiment, the circuit includes a first transistor having a source connected to a supply voltage, a gate connected to a delayed clock signal, and a drain, a second transistor having a source connected to the drain of the first transistor, a gate connected to a clock signal, and a drain connected to the outputs of the logic block.

Method and apparatus for fast evaluation of dynamic CMOS logic circuits

A multiplier circuit within a CPU has its selections of partial products reordered in a unique manner so that shift left capabilities are eliminated and the hardware is required to only perform shift right operations. This allows for reduced circuit sizes in several components within the multiplier circuit in order to save area, speed computation time, and reduce power consumption on the chip.

System and method for multiplying in a data processing system

A cache memory system includes a plurality of processors and a plurality of caches respectively assigned to the plurality of processors. Each cache is mapped to a different region of the main memory, so that memory contention is lessened to a great extent. Based on a memory address received by a cache, the cache compares the memory address to its assigned region of addresses. If the memory address falls within the assigned region for the cache, the cache then examines its contents as to determine if there is an address hit in the cache. If the memory address does not fall within the assigned region for the cache, the cache does not examine its contents to determine if there is an address hit in the cache, since an address hit is not possible in that case.

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Austin, TX, United States of America

Salim Ahmed Shah