In this unusual case, (len + 1) is zero, the allocation in vstr_init
succeeds (allocating 1 byte), and then the caller is likely to erroneously
access outside the allocated region, for instance with a memset().
This could be triggered with os.urandom(-1) after it was converted to use
mp_obj_new_bytes_of_zeros.
PacketBuffer facilitates packet oriented BLE protocols such as BLE
MIDI and the Apple Media Service.
This also adds PHY, MTU and connection event extension negotiation
to speed up data transfer when possible.
Instances of the slice class are passed to __getitem__() on objects when
the user indexes them with a slice. In practice the majority of the time
(other than passing it on untouched) is to work out what the slice means in
the context of an array dimension of a particular length. Since Python 2.3
there has been a method on the slice class, indices(), that takes a
dimension length and returns the real start, stop and step, accounting for
missing or negative values in the slice spec. This commit implements such
a indices() method on the slice class.
It is configurable at compile-time via MICROPY_PY_BUILTINS_SLICE_INDICES,
disabled by default, enabled on unix, stm32 and esp32 ports.
This commit also adds new tests for slice indices and for slicing unicode
strings.
In CPython, EnvironmentError and IOError are now aliases of OSError so no
need to have them listed in the code. OverflowError inherits from
ArithmeticError because it's intended to be raised "when the result of an
arithmetic operation is too large to be represented" (per CPython docs),
and MicroPython aims to match the CPython exception hierarchy.
For the 3 ports that already make use of this feature (stm32, nrf and
teensy) this doesn't make any difference, it just allows to disable it from
now on.
For other ports that use pyexec, this decreases code size because the debug
printing code is dead (it can't be enabled) but the compiler can't deduce
that, so code is still emitted.
The qst value is always small enough to fit in 31-bits (even less) and
using a 32-bit shift rather than a 64-bit shift reduces code size by about
300 bytes.
A user-defined type that defines __iter__ doesn't need any memory to be
pre-allocated for its iterator (because it can't use such memory). So
optimise for this case by not allocating the iter-buf.
In commit 71a3d6ec3bd02c5bd13334537e1bd146bb643bad mp_setup_code_state was
changed from a 5-arg function to a 4-arg function, and at that point 5-arg
calls in native code were no longer needed. See also commit
4f9842ad80c235188955fd83317f715033a596c0.
Allows assigning attributes on class instances that implement their own
__setattr__. Both object.__setattr__ and super(A, b).__setattr__ will work
with this commit.
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).
By having an order-only dependency on the directory itself, the directory
is sure to be created before the rule to create a .mo file is.
This fixes a low-freqency error on github actions such as
> msgfmt: error while opening "build/genhdr/en_US.mo" for writing: No such file or directory
These s16-s21 registers are used by gcc so need to be saved. Future
versions of gcc (beyond v9.1.0), or other compilers, may eventually need
additional registers saved/restored.
See issue #4844.
Recent versions of gcc perform optimisations which can lead to the
following code from the MP_NLR_JUMP_HEAD macro being omitted:
top->ret_val = val; \
MP_NLR_RESTORE_PYSTACK(top); \
*_top_ptr = top->prev; \
This is noticeable (at least) in the unix coverage on x86-64 built with gcc
9.1.0. This is because the nlr_jump function is marked as no-return, so
gcc deduces that the above code has no effect.
Adding MP_UNREACHABLE tells the compiler that the asm code may branch
elsewhere, and so it cannot optimise away the code.
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.
