jit.zone (Profiler Zones) Reference

Module defined in lua/common/jit/zone.lua. Implements a simple hierarchical zone stack for the LuaJIT profiler. Zones label code sections for profiling output.

Exports

Returns a callable table (via __call metamethod) - no traditional M exports.

Usage

local zone = require("jit.zone")
zone("AI")        -- push zone
zone("A*")        -- push nested zone
print(zone:get()) -- "A*"
zone()            -- pop "A*"
print(zone:get()) -- "AI"
zone()            -- pop "AI"

Methods

zone(name)

Push a named zone onto the stack. Call with no arguments to pop.

• Parameters:
  • name - string|nil - Zone name to push, or nil to pop
• Returns: string - The popped zone name (when popping)

zone:get()

Get the current (topmost) zone name.

• Returns: string|nil - Current zone name

zone:flush()

Clear the entire zone stack.

Internal Notes

• Implemented as a plain table with metatable __call
• Stack is the table itself (integer-indexed)
• Popping an empty stack triggers an assertion error
• Used with jit.p z flag to show zones in profiler output