ruby-x/rubyx
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

polish docs

Browse Source 
and a bit of code style
This commit is contained in:
Torsten Ruger
2018-03-11 16:11:15 +05:30
parent d6a2ea4cfc
commit f7aac1d1a4
14 changed files with 65 additions and 72 deletions
Download Patch File Download Diff File Expand all files Collapse all files

25
lib/risc/README.md
View File

@ -1,5 +1,4 @@
Risc Machine
================
# Risc Machine
The RiscMachine, is an abstract machine with registers. Think of it as an arm machine with
normal instruction names. It is not however an abstraction of existing hardware, but only
@ -17,31 +16,29 @@ All data is in objects.
The register machine is aware of Parfait objects, and specifically uses Message and Frame to
express call semantics.
Calls and syscalls
------------------
## Calls and syscalls
The RiscMachine only uses 1 fixed register, the currently worked on Message.
The RiscMachine only uses 1 fixed register, the currently worked on Message. (and assumes a
program counter and flags, neither of which are directly manipulated)
There is no stack, rather messages form a linked list, and preparing to call, the data is pre-filled
into the next message. Calling then means moving the new message to the current one and jumping
to the address of the method. Returning is the somewhat reverse process.
There is no stack, rather messages form a linked list, and preparing to call, the data is
pre-filled into the next message. Calling then means moving the new message to the current
one and jumping to the address of the method. Returning is the somewhat reverse process.
Syscalls are implemented by *one* Syscall instruction. The Risc machine does not specify/limit
the meaning or number of syscalls. This is implemented by the level below, eg the arm/interpreter.
Interpreter
===========
## Interpreter
There is an interpreter that can interpret compiled register machine programs.
This is very handy for debugging (an nothing else).
This is very handy for debugging (and nothing else).
Even more handy is the graphical interface for the interpreter, which is in it's own repository:
rubyx-debugger.
Arm / Elf
=========
## Arm / Elf
There is also a (very strightforward) transformation to arm instructions.
There is also a (very straightforward) transformation to arm instructions.
Together with the also quite minimal elf module, arm binaries can be produced.
These binaries have no external dependencies and in fact can not even call c at the moment