Shader Variable Packing in GPU Pipelines

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The conventional graphics processing unit (GPU) pipelines, such as those using OpenGL, face inefficiencies in packing and linking shader variables, leading to suboptimal memory usage, increased traffic bandwidth, and reduced performance due to the fixed functionality and limitations in vertex and fragment shaders.

Innovation Solution

Implementing a system with shared M-dimensional registers and a processing unit that packs multiple shader variables into each register, allowing for efficient packing and linking of shader variables, thereby reducing memory usage and bandwidth while improving performance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If shader variables are stored in separate registers without packing, then each variable has dedicated storage space, but memory usage increases and bandwidth traffic increases

Engineering Contradiction:
Improvememory usageVSAvoidperformance
Core Design Contradiction:
Quantity of substanceVSProductivity

Solution Approach 1:

The patent merges multiple shader variables into a single register by packing them together. Specifically, it packs four half-precision float variables (2 bytes each) into one register, reducing the total number of registers needed from 8 to 2. This combining approach directly reduces memory usage and bandwidth traffic while maintaining computational functionality.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent changes the storage parameter from separate register allocations to packed register allocations. By modifying how variables are organized in memory (from individual registers to packed registers), the system achieves more efficient memory usage without sacrificing the ability to process these variables through the shader pipeline.

Inventive Principle:
Principle #35Parameter changes

2Adaptability or versatility

If fixed functionality is used in GPU pipelines, then hardware design is simplified, but adaptability and performance are limited

Engineering Contradiction:
Improveshader functionalityVSAvoidpipeline complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent introduces dynamic packing and linking mechanisms that allow the system to adapt to different shader variable configurations. Instead of fixed register allocations, the system dynamically packs variables based on their types and sizes, and dynamically links them through the pipeline. This dynamic approach provides versatility while managing complexity through algorithmic optimization.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent performs preliminary packing and linking operations during the shader compilation or setup phase. By pre-organizing variables into packed registers and establishing linking relationships before execution, the system prepares the pipeline for efficient operation. This preliminary action reduces runtime complexity and enables more adaptable functionality without increasing operational complexity.

Inventive Principle:
Principle #10Preliminary action

3Loss of energy

If more shader variables are packed into registers, then memory efficiency improves and bandwidth reduces, but register allocation complexity increases

Engineering Contradiction:
Improvepower consumptionVSAvoidpacking complexity
Core Design Contradiction:
Loss of energyVSDevice complexity

Solution Approach 1:

The patent changes the parameter of variable organization from individual register assignments to packed register assignments. By modifying the storage parameter to pack multiple variables into fewer registers, the system reduces memory traffic and power consumption. The complexity is managed by optimizing the packing algorithm to handle different variable types and sizes systematically.

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP2023285B8Scheme for packing and linking of variables in graphics systems
Publication Date: 2018.06.27 QUALCOMM INC

AI summary

A wireless device which performs a first-level compiler packing process and a second-level hardware packing process on varyings. The compiler packing process packs two or more shader variables (varyings or attributes) whose sum of components equals M into a shared M-dimensional (MD) vector register. The hardware packing consecutively packs M components of the shader variables (varyings or attributes) and any remaining variables into a vertex cache or other storage medium.