问题:

Can anyone tell me where to find Lua's bytecode specification? I've been searching for 15 minutes, and I can't find anything.

回答1:

Maybe A No-Frills Introduction to Lua 5.1 VM Instructions contains what you're looking for?

There is also a table of the Lua 5.0 instruction set (Figure 5) in:

Ierusalimschy, R.; Figueiredo, L. H.; Celes, W. (2005), "The implementation of Lua 5.0", J. of Universal Comp. Sci. 11 (7): 1159-1176

You can find the full text with a search on Google Scholar and I believe it's on lua.org as well. This reference is used by the Lua page on Wikipedia, which is always a good place to look for such things. :-)

回答2:

The official definition is in lopcodes.h.

回答3:

The only specifications for Lua are the language, standard libraries, and the C API. The creators of Lua intentionally left the VM unspecified for a couple main reasons:

Lua can be fully implemented with any underlying architecture (VM, interpreter, compiler, etc.)
The official Lua distribution doesn't have to worry about maintaining VM compatibility between versions

This means, for example, that you generally shouldn't use the Lua VM as a target for a compiler. If you'd like to know how the official Lua distribution's VM works as an example for your own curiosity, see the other answers.