February 2026 — OpenXiangShan/XiangShan: Delivered a targeted configuration naming refactor with explicit bus protocol prefixes and stabilized CI by fixing the swapfile path. Both changes preserve backward compatibility while clarifying defaults and improving CI reliability. Business value includes reduced misconfigurations, smoother transition to default CHI configurations, and more predictable resource allocation in CI pipelines. Technologies demonstrated include refactoring with backward-compatibility strategy, PR-level documentation, and CI/configuration management.

December 2025: Delivered cross-repo sequence processing, simulation performance improvements, and FIRRTL/Chisel integration refinements across Utility and XiangShan. Implemented core sequence utilities to enable robust preprocessing and data augmentation for sequence-based models, optimized the Rename Buffer path for faster simulation, advanced the FIRRTL/Chisel transformation pipeline with LayerBlock handling and direct .fir serialization, and performed targeted codebase cleanup to reduce maintenance burden. These efforts collectively boost model prep throughput, simulator efficiency, and code maintainability for future features.

2025-11 monthly summary for OpenXiangShan/XiangShan. Focused on modernizing the build surface by upgrading the Chisel library and its dependencies to improve compatibility and future feature readiness. Delivered a version bump with minimal surface changes, aligning the codebase with newer tooling and dependency ecosystems.

October 2025 summary for OpenXiangShan/difftest: Focused on hardening the gateway path by fixing width initialization. Delivered an explicit width specification for the packed wire in Gateway.scala to prevent implicit width inference issues and improve type safety. This change reduces synthesis/runtime risk and improves gateway reliability in production.

September 2025 performance summary focused on reliability, build integrity, and future-readiness across the OpenXiangShan and levizh/rt-thread portfolios. Delivered critical driver/hardware access hardening, hardened RISC-V/klibc build flows, and modernization of the Chisel-based stack to support upcoming hardware features and faster iteration cycles.

In August 2025, completed forward-looking, cross-repo work across OpenXiangShan to improve compatibility with Chisel 6, strengthen observability, and streamline integration. The work focuses on modernizing wiring and wiring-utils, syncing test vectors, and adding configurable performance hooks to support debugging and optimization without impacting runtime behavior. These changes reduce maintenance risk, improve developer productivity, and enable safer platform evolution for future hardware and tooling updates.

Concise monthly summary for 2025-07 highlighting reliability improvements in power-down sequencing and expanded CVM configurability for OpenXiangShan/XiangShan. Focused on delivering business value through robust interrupt handling during power-off and finer-grained CVM controls, enabling secure, configurable deployment scenarios with lower risk of misconfiguration.

Month: 2025-06 summary for OpenXiangShan/XiangShan development. Key features delivered include a power-off verification workflow and configuration updates that enable CI to upload and verify low-power Verilog, generate standalone devices, compile with difftest enabled, archive artifacts, and adjust Poweroff.yml to set geilen parameter to 7. A new Simulation debugging trigger via a custom HINT instruction was introduced, with updates to the decode unit, rename unit, and ROB to support simulation control during runs. Internal refactors simplified reset logic and datapath wiring by removing RegNext usage in ram_ctl connections and eliminating the redundant hartIsInReset reset condition in L2Top. These changes collectively improve verification coverage for low-power designs, accelerate debugging cycles, and reduce maintenance risk through cleaner reset paths. Technologies demonstrated include Verilog low-power design practices, CI/CD workflow integration, difftest-enabled builds, custom instruction-based debugging, and targeted code refactors for reset and wiring stability.

Monthly work summary for 2025-05 focusing on reliability and correctness in hardware design across OpenXiangShan repositories. Highlights include 3-cycle reset synchronization defaults for ResetGen to improve reset robustness, and fixes to control-flow translation in SV48x4 jumps/branches. These changes increase bring-up stability, reduce metastability risk, and improve firmware/hardware integration readiness. Work spanned two repositories: OpenXiangShan/Utility and OpenXiangShan/XiangShan, with traceable commits across the ResetGen and PC sign/zero-extension areas.

April 2025 monthly review: Delivered targeted features, stability improvements, and process optimizations across the OpenXiangShan stack. Key outcomes include modular clock multiplexing for MbistClockGateCell, extensive dependency and tooling maintenance, configurable system parameters for runtime flexibility, clearer DFT/SRAM test interfaces, a Difftest PC correctness fix, CI workflow optimization for Spike-so, and new RVSE'25 documentation pages. These efforts improved hardware validation reliability, CI efficiency, and developer productivity, while enabling more scalable feature development.

March 2025 was focused on improving testability, configurability, and reliability across the XiangShan project and related repositories. Key features were delivered to harden test workflows, enable flexible hardware configurations, and enhance observability, while stability fixes reduced risk in reset/interrupt paths. Cross-repo efforts included an initial ChiselAIA integration into XiangShan with submodule updates (followed by rollback to stabilize the codebase) and groundwork for modular IMSIC configurations. The team also modernized CI/build tooling, updated documentation, and prepared the grounds for future hardware scaling. Overall, these efforts reduce regression risk, speed validation cycles, and enable easier customization for different deployment scenarios.

February 2025: Delivered automated CI-driven artifact generation and upload for Issue E.b in OpenXiangShan/XiangShan, upgraded build pipeline to support Chisel 6 with stability improvements, and enhanced testing observability. These changes streamline releases, reduce manual maintenance, and improve debugging across critical components.

January 2025 delivered cross-repo Zawrs/ISA extensions, reinforced difftest validation, and modernized configuration and CI pipelines across OpenXiangShan components. These efforts expanded simulator coverage, improved runtime correctness, and accelerated upstream alignment with Spike/NEMU while simplifying maintenance and configuration.

December 2024 monthly summary: Delivered key software and hardware design improvements across XiangShan and its documentation. Key outcomes include bug fixes that improve correctness of vector state tracking and AXI4 interrupt data handling, ISA extension support expansion, and an enhanced build/test infrastructure enabling configurable JVM memory and caches. Also updated event scheduling docs for HPCA'25 and MICRO'24. These changes increase system reliability, ISA coverage, and engineering efficiency, delivering business value through more deterministic behavior, faster validation, and easier operations.

November 2024 monthly summary: Delivered meaningful business and technical value across XiangShan repos through enhancements to documentation, ISA configurability, and build/CI infrastructure. The work spanned XiangShan-doc, XiangShan, and the Mill-based build ecosystem, aligning with roadmap goals for clearer documentation, flexible ISA configuration, and faster iteration cycles.

October 2024: Focused on correctness and reliability across the OpenXiangShan codebases (NEMU and XiangShan). No new user-facing features were shipped this month. Primary work centered on stabilizing processor state during vector operations and strengthening CI pipeline reliability. The month delivered targeted fixes that improve correctness, reduce risk, and enhance maintainability for future development.

OpenXiangShan/XiangShan – Sep 2024 monthly summary: Delivered a critical bug fix updating the XiangShan simulation checkpoint path to align with a new storage layout, enabling reliable access to required checkpoint and JSON files for simulations. The change was implemented in the XiangShan script and reflected in the nightly CI workflow to ensure the correct checkpoint directory is used during automated builds. These updates improved simulation reliability, reproducibility, and deployment readiness, reducing nightly build interruptions and downstream debugging effort. Technologies demonstrated include scripting for path resolution, CI/configuration updates, and end-to-end validation of simulation resources.

Month: 2024-08. Repo: OpenXiangShan/riscv-isa-sim. Key features delivered: Implemented a continuous integration and automated build pipeline for spike-so, enabling automated builds and PR validation. This work was merged as part of commit 1c855f0a4b353cb40717f5a4271314f1d36f0ca1 (Merge pull request #27 from OpenXiangShan/difftest-ci). Major bugs fixed: None reported this period; focus was on CI infrastructure. Overall impact and accomplishments: Faster feedback loops, improved build reliability, and stronger release readiness, underpinning upcoming features and quality improvements. Technologies/skills demonstrated: CI/CD tooling, build automation, Git workflows, and cross-team collaboration with spike-so integration.