Tag: performance - 2026

• Caching a Z80 Decoder

  2026-02-07 | Series: debug80diaries | Tags: debug80, z80, decoder, performance, caching

  The Z80 instruction decoder for Debug80 grew to 1,616 lines of switch statements and lookup tables. I split it into prefix-based modules and added WeakMap caching so that each unique instruction decodes only once. The cache key is the instruction bytes themselves. The hit rate in typical programs exceeds 95 percent.

• Caching Debug Maps Plus Streamlining the Debugger Workflow

  2026-01-28 | Series: debug80diaries | Tags: debug80, vscode, caching, performance, debugging

  Debug80 regenerated its debug maps on every session start even when the underlying source had not changed. I added content-hash based caching to skip redundant work then tackled two quality-of-life improvements: auto-opening source files plus consolidating the memory panel.