This makes the loading of viper-code-with-relocations a bit neater and
easier to understand, by treating the rodata/bss like a special object to
be loaded into the constant table (which is how it behaves).
Because CPython 3.8.0 now produces different output:
- basics/parser.py: CPython does not allow '\\\n' as input.
- import/import_override: CPython imports _io.
We don't want to add a feature flag to .mpy files that indicate float
support because it will get complex and difficult to use. Instead the .mpy
is built using whatever precision it chooses (float or double) and the
native glue API will convert between this choice and what the host runtime
actually uses.
This commit adds a new tool called mpy_ld.py which is essentially a linker
that builds .mpy files directly from .o files. A new header file
(dynruntime.h) and makefile fragment (dynruntime.mk) are also included
which allow building .mpy files from C source code. Such .mpy files can
then be dynamically imported as though they were a normal Python module,
even though they are implemented in C.
Converting .o files directly (rather than pre-linked .elf files) allows the
resulting .mpy to be more efficient because it has more control over the
relocations; for example it can skip PLT indirection. Doing it this way
also allows supporting more architectures, such as Xtensa which has
specific needs for position-independent code and the GOT.
The tool supports targets of x86, x86-64, ARM Thumb and Xtensa (windowed
and non-windowed). BSS, text and rodata sections are supported, with
relocations to all internal sections and symbols, as well as relocations to
some external symbols (defined by dynruntime.h), and linking of qstrs.
Usage:
mpy-tool.py -o merged.mpy --merge mod1.mpy mod2.mpy
The constituent .mpy files are executed sequentially when the merged file
is imported, and they all use the same global namespace.
Implements text, rodata and bss generalised relocations, as well as generic
qstr-object linking. This allows importing dynamic native modules on all
supported architectures in a unified way.
The size of the event ringbuf was previously fixed to compile-time config
value, but it's necessary to sometimes increase this for applications that
have large characteristic buffers to read, or many events at once.
With this commit the size can be set via BLE.config(rxbuf=512), for
example. This also resizes the internal event data buffer which sets the
maximum size of incoming data passed to the event handler.
