Thanks all for the links and suggestions, they are greatly appreciated. I might be programming for a long time (relative to my age) but I haven't touched much on compilers or interpreters. Inspired a but by Python's interpreter I wrote a little bytecode interpreter in C (maybe should have upgrade to C++ but not yet), I enter custom bytes into a program array, currently can jump, add/subtract, print values on stack and halt the interpreter. I'm happy with what I've done so far. A compiler is out of my reach for the moment so I'm going to research that after learning a good bit of Python's internals.
On Wed 10 Jan 2018, 12:13 bartc, <b...@freeuk.com> wrote: > On 09/01/2018 20:12, Alain Ketterlin wrote: > > ElChino <elch...@cnn.cn> writes: > > > >> Chris Angelico wrote: > >> > >>> CPython is a stack-based interpreter, which means it loads values onto > >>> an (invisible) internal stack, processes values at the top of the > >>> stack, and removes them when it's done. > >> > >> Is this similar to how Lua operates too? > > > > No. Lua uses a register-based (virtual) machine. See > > > > https://www.lua.org/doc/jucs05.pdf > > "Registers are kept in the run-time stack ... an array". > > So it sounds like a stack is still used, but instructions directly > access specific slots on the stack, within a particular register window. > > It means there need be fewer instructions to implement some code, but > each has more operands. > > Also interesting is that the comparison operators include only EQ, LT > and LE. There is no NE, so no issues such as those discussed recently. > > > > > I think Lua was the first language in widespread use to move to a > > register-based machine. > > I believe stack-based byte-code, which is very easy to generate, can be > transformed to some 'register'-based version, if performance is the > motivation. > > (But I'm not convinced that register-based is necessarily faster. Lua is > quite fast, especially LuaJIT, but the language is also smaller and > simpler.) > > -- > bartc > -- > https://mail.python.org/mailman/listinfo/python-list > -- https://mail.python.org/mailman/listinfo/python-list
