xenia-project/xenia

Optimize byte swapping routines in memory_generic.cc

Open

#308 opened on Jun 29, 2015

View on GitHub
 (0 comments) (0 reactions) (0 assignees)C++ (1,077 forks)batch import
cpugood first issue

Repository metrics

Stars
 (7,418 stars)
PR merge metrics
 (No merged PRs in 30d)

Description

AVX intrinsics and unrolled loops could help swap large chunks of memory much faster.

Contributor guide

Research direction
Examine the current byte swapping implementation in memory generic.cc. Identify the hot loop. Study AVX intrinsics (e.g., mm256 shuffle epi8) to swap bytes in 256 bit chunks. Implement an unrolled version and benchmark using Google Benchmark or a simple timing test. Ensure correctness by comparing with original.
Tech stack
cpp
Domain
backend
Issue type
Performance
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
Half day
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
GitC++
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
30