Compile-Time Hotspots

A VS Code extension to help C++ developers understand, visualize, and optimize their compile-time performance.

Features

• Raw Analysis
  Use GCC’s -ftime-report to get a phase-by-phase breakdown of where your compiler spends time.

• Include Graph
  With -H you can see which headers are included most frequently or to the greatest depth.

• Build-Cache Heatmap
  Track incremental build times for a selected translation unit over your last 20 builds. Colors range from light (fast) to dark red (slow).

• Live Analysis
  Start/stop on-demand live compile-time feedback in a dedicated view, so you can instantly see how your edits affect compilation.

• Cache Management
  Clear previous build history with a single command to reset measurements.

Usage

1. Open the Command Palette
   Press Ctrl+Shift+P (Windows/Linux) or Cmd+Shift+P (macOS).

2. Type Compile-Time Hotspots:
   Then pick any of the following commands:

   • Raw Analysis — Compile-Time Hotspots: Raw Analysis
   • Include Graph — Compile-Time Hotspots: Include Graph
   • Build-Cache Heatmap — Compile-Time Hotspots: Build-Cache Heatmap
   • Start Live Analysis — Compile-Time Hotspots: Start Live Analysis
   • Stop Live Analysis — Compile-Time Hotspots: Stop Live Analysis
   • Clear Cache — Compile-Time Hotspots: Clear Cache

3. Follow any prompts
   You’ll be asked to select a .cpp (or header) file, and output panels or the Live view will display results.

Requirements

• GCC / g++ installed and on your PATH.
  The extension invokes g++ -ftime-report, g++ -H, and g++ -ftime-report -fsyntax-only under the hood.
• Windows users: when working in WSL, ensure you open the folder via the \\wsl$ path so the extension can invoke Linux GCC.

Extension Settings

This extension contributes no custom settings.

Known Issues

• If your code has compilation errors, the raw analysis command will show the GCC error output instead of metrics.
• Very large projects may see a slight pause while running -H or -ftime-report.
• Live analysis currently only runs a syntax-only compile on the active file, so cross-file dependencies will not be reflected.

Changelog

0.1.0

• Initial release
  • Raw Analysis (-ftime-report)
  • Include Graph (-H)
  • Build-Cache Heatmap
  • Manual start/stop Live Analysis
  • Clear Cache command

Enjoy faster builds!