Just In Time Compiler

See JustInTimeCompilation.

A Just In Time (JIT) Compiler converts ByteCode to executable machine instructions on the fly. As a consequence, it differs in subtle ways from a traditional compiler. First off, since many problems (example, RegisterAllocation) are computationally complex, a JIT Compiler uses fast heuristics instead of well established, but slower, algorithms. This may result in sub-optimal results. However, as a benefit, JIT Compilers have access to the code as it is running, and as such may dynamically determine code segments to be optimized to a greater degree.

Examples of JIT Compilers include:

• Sun Microsystems HotSpot JVM,
• IBM's Jikes RVM (ResearchVirtualMachine),
• Microsoft's .Net JIT (name unknown), and
• The Mono project's .Net JIT.
• SpiderMonkey's tracing JIT (https://developer.mozilla.org/en/SpiderMonkey/Internals/Tracing_JIT)
• LuaLanguage's LuaJIT (http://luajit.org)

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CategoryTime CategoryCompilers