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).
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.
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.
With the memcpy() call placed last it avoids the effects of registers
clobbering. It's definitely effective in non-inlined functions, but even
here it is still making a small difference. For example, on stm32, this
saves an extra `ldr` instruction to load `o->vstr` after the memcpy()
returns.
The string length being longer than the allowed qstr length can happen in
many locations, for example in the parser with very long variable names.
Without an explicit check that the length is within range (as done in this
patch) the code would exhibit crashes and strange behaviour with truncated
strings.
This commit adds a sys.implementation.mpy entry when the system supports
importing .mpy files. This entry is a 16-bit integer which encodes two
bytes of information from the header of .mpy files that are supported by
the system being run: the second and third bytes, .mpy version, and flags
and native architecture. This allows determining the supported .mpy file
dynamically by code, and also for the user to find it out by inspecting
this value. It's further possible to dynamically detect if the system
supports importing .mpy files by `hasattr(sys.implementation, 'mpy')`.
Replace the is_running field with a tri-state variable to indicate
running/not-running/pending-exception.
Update tests to cover the various cases.
This allows cancellation in uasyncio even if the coroutine hasn't been
executed yet. Fixes#5242
This wasn't necessary as the wrapped function already has a reference to
its globals. But it had a dual purpose of tracking whether the function
was currently running, so replace it with a bool.
Damien George
Emil Renner Berthing
Yonatan Goldschmidt
Léa Saviot
Petr Viktorin
Jim Mussared
Andrew Leech
Thea Flowers