Register Renaming With Data Type Prediction for Clustered Register Files

Solution Overview

Problem

Modern processors face inefficiencies in power consumption and circuit delays due to the handling of different data types in unified physical register files, particularly in out-of-order execution systems, where write-after-write and write-after-read hazards are not adequately addressed by conventional register renaming techniques.

Innovation Solution

Implementing a processor architecture with separate clusters for different data types, using register renaming based on data type prediction to optimize storage and processing, and employing localized processing within these clusters to reduce energy consumption and circuit delays.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a unified physical register file is used to hold different data types, then device complexity is reduced, but energy consumption increases and circuit delays worsen

Engineering Contradiction:

Improveregister file structureVSAvoidenergy consumption

Core Design Contradiction:

Device complexityVSUse of energy by moving object

Solution Approach 1:

The unified physical register file is segmented into multiple specialized clusters, each dedicated to specific data types (integer, floating-point, vector). This segmentation allows each cluster to be optimized for its specific data type, reducing energy consumption and circuit delays while maintaining manageable complexity through modular architecture.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the register file are assigned different qualities and characteristics tailored to their specific data types. Each cluster has optimized routing and access patterns suited to its data type, improving energy efficiency and performance while reducing the need for complex data conversion across the entire register file.

Inventive Principle:

Principle #3Local quality

2Device complexity

If a unified physical register file is used to hold different data types, then device complexity is reduced, but circuit delays increase

Engineering Contradiction:

Improveregister file structureVSAvoidcircuit delay

Core Design Contradiction:

Device complexityVSSpeed

Solution Approach 1:

The unified physical register file is segmented into multiple specialized clusters, each dedicated to specific data types (integer, floating-point, vector). This segmentation allows each cluster to be optimized for its specific data type, reducing energy consumption and circuit delays while maintaining manageable complexity through modular architecture.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the register file are assigned different qualities and characteristics tailored to their specific data types. Each cluster has optimized routing and access patterns suited to its data type, improving energy efficiency and performance while reducing the need for complex data conversion across the entire register file.

Inventive Principle:

Principle #3Local quality

3Reliability

If conventional register renaming is used, then write-after-write and write-after-read hazards are addressed, but energy consumption and circuit delays remain inefficient

Engineering Contradiction:

Improvehazard resolutionVSAvoidenergy consumption

Core Design Contradiction:

ReliabilityVSUse of energy by moving object

Solution Approach 1:

The register renaming mechanism is enhanced by segmenting the register file into specialized clusters. When renaming occurs, the system can allocate registers within the appropriate cluster for the specific data type, reducing the need for cross-cluster data movement and associated energy consumption and delays.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The prediction mechanism acts as an intermediary that anticipates the data type of register results before allocation occurs. This allows the register renaming circuit to pre-determine the optimal cluster allocation, avoiding subsequent data type conversions and reducing energy consumption and circuit delays while maintaining hazard resolution.

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS12468540B2Technologies for prediction-based register renaming

Publication Date: 2025.11.11 SIFIVE INC

AI summary

Systems and methods are disclosed for register renaming. For example, an integrated circuit is described that includes a first cluster including a first set of physical registers and a first execution resource circuit, wherein the inputs for operations of the first execution resource circuit are of a first data type; a second cluster including a second set of physical registers and a second execution resource circuit, wherein the inputs for operations of the second execution resource circuit are of a second data type that is different than the first data type; and a register renaming circuit configured to: determine a data type prediction for a result of a first instruction that will be mapped to a first logical register; and, based on the data type prediction matching the first data type, rename the first logical register to be mapped to a physical register of the first set of physical registers.