66ae8c9f49
Things get tricky when using the nlr code to catch exceptions. Need to ensure that the variables (stack layout) in the exception handler are the same as in the bit protected by the exception handler. Prior to this patch there were a few bugs. 1) The constant mp_const_MemoryError_obj was being preloaded to a specific location on the stack at the start of the function. But this location on the stack was being overwritten in the opcode loop (since it didn't think that variable would ever be referenced again), and so when an exception occurred, the variable holding the address of MemoryError was corrupt. 2) The FOR_ITER opcode detection in the exception handler used sp, which may or may not contain the right value coming out of the main opcode loop. With this patch there is a clear separation of variables used in the opcode loop and in the exception handler (should fix issue (2) above). Furthermore, nlr_raise is no longer used in the opcode loop. Instead, it jumps directly into the exception handler. This tells the C compiler more about the possible code flow, and means that it should have the same stack layout for the exception handler. This should fix issue (1) above. Indeed, the generated (ARM) assembler has been checked explicitly, and with 'goto exception_handler', the problem with &MemoryError is fixed. This may now fix problems with rge-sm, and probably many other subtle bugs yet to show themselves. Incidentally, rge-sm now passes on pyboard (with a reduced range of integration)! Main lesson: nlr is tricky. Don't use nlr_push unless you know what you are doing! Luckily, it's not used in many places. Using nlr_raise/jump is fine. |
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| bare-arm | ||
| examples | ||
| logo | ||
| py | ||
| stm | ||
| stmhal | ||
| teensy | ||
| tests | ||
| tools | ||
| unix | ||
| unix-cpy | ||
| windows | ||
| .gitignore | ||
| .travis.yml | ||
| CODECONVENTIONS.md | ||
| LICENSE | ||
| README.md | ||
README.md
[![Build Status][travis-img]][travis-repo] [travis-img]: https://travis-ci.org/micropython/micropython.png?branch=master [travis-repo]: https://travis-ci.org/micropython/micropython
The Micro Python project
This is the Micro Python project, which aims to put an implementation of Python 3.x on a microcontroller.
WARNING: this project is in its early stages and is subject to large changes of the code-base, including project-wide name changes and API changes.
See the repository www.github.com/micropython/pyboard for the Micro Python board.
Major components in this repository:
- py/ -- the core Python implementation, including compiler and runtime.
- unix/ -- a version of Micro Python that runs on Unix.
- stmhal/ -- a version of Micro Python that runs on the Micro Python board with an STM32F405RG (using ST's new Cube HAL drivers).
- teensy/ -- a version of Micro Python that runs on the Teensy 3.1 (preliminary but functional).
Additional components:
- bare-arm/ -- a bare minimum version of Micro Python for ARM MCUs. Start with this if you want to port Micro Python to another microcontroller.
- stm/ -- obsolete version of Micro Python for the Micro Python board that uses ST's old peripheral drivers.
- unix-cpy/ -- a version of Micro Python that outputs bytecode (for testing).
- tests/ -- test framework and test scripts.
- tools/ -- various tools, including the pyboard.py module.
- examples/ -- a few example Python scripts.
"make" is used to build the components, or "gmake" on BSD-based systems. You will also need bash and Python (at least 2.7 or 3.3).
The Unix version
The "unix" port requires a standard Unix environment with gcc and GNU make. x86 and x64 architectures are supported (i.e. x86 32- and 64-bit), as well as ARMv7. Porting to other architectures require writing some assembly code for the exception handling.
To build:
$ cd unix
$ make
Then to test it:
$ ./micropython
>>> list(5 * x + y for x in range(10) for y in [4, 2, 1])
Debian/Ubuntu/Mint derivative Linux distros will require build-essentials and libreadline-dev packages installed. To build FFI (Foreign Function Interface) module, libffi-dev package is required. If you have problems with some dependencies, they can be disabled in unix/mpconfigport.mk .
The STM version
The "stmhal" port requires an ARM compiler, arm-none-eabi-gcc, and associated bin-utils. For those using Arch Linux, you need arm-none-eabi-binutils and arm-none-eabi-gcc packages from the AUR. Otherwise, try here: https://launchpad.net/gcc-arm-embedded
To build:
$ cd stmhal
$ make
You then need to get your board into DFU mode. On the pyboard, connect the 3V3 pin to the P1/DFU pin with a wire (on PYBv1.0 they are next to each other on the bottom left of the board, second row from the bottom).
Then to flash the code via USB DFU to your device:
$ dfu-util -a 0 -D build/flash.dfu
You will need the dfu-util program, on Arch Linux it's dfu-util-git in the AUR.