The loop searches backwards for a target, but doesn't stop after finding
the first result, meaning that it'll always end up at the outermost
exception handler.
This previously made the native emitter incompatible with the bytecode
emitter, and mp_resume (and subsequently mp_obj_generator_resume) expects
the bytecode emitter behavior (i.e. throw==NULL).
Commit d96cfd13e3 introduced a regression in
testing for bool objects, that such objects were in some cases no longer
recognised and bools, eg when using mp_obj_is_type(o, &mp_type_bool), or
mp_obj_is_integer(o).
This commit fixes that problem by adding mp_obj_is_bool(o). Builds with
MICROPY_OBJ_IMMEDIATE_OBJS enabled check if the object is any of the const
True or False objects. Builds without it use the old method of ->type
checking, which compiles to smaller code (compared with the former
mentioned method).
Fixes#5538.
When threads and the GIL are enabled, then the qstr mutex is not needed.
The qstr_mutex field is never used in this case because of:
#if MICROPY_PY_THREAD && !MICROPY_PY_THREAD_GIL
#define QSTR_ENTER() mp_thread_mutex_lock(&MP_STATE_VM(qstr_mutex), 1)
#define QSTR_EXIT() mp_thread_mutex_unlock(&MP_STATE_VM(qstr_mutex))
#else
#define QSTR_ENTER()
#define QSTR_EXIT()
#endif
So, we can completely remove qstr_mutex everywhere when MICROPY_PY_THREAD
&& !MICROPY_PY_THREAD_GIL.
When threads and the GIL are enabled, then the GC mutex is not needed. The
gc_mutex field is never used in this case because of:
#if MICROPY_PY_THREAD && !MICROPY_PY_THREAD_GIL
#define GC_ENTER() mp_thread_mutex_lock(&MP_STATE_MEM(gc_mutex), 1)
#define GC_EXIT() mp_thread_mutex_unlock(&MP_STATE_MEM(gc_mutex))
#else
#define GC_ENTER()
#define GC_EXIT()
#endif
So, we can completely remove gc_mutex everywhere when MICROPY_PY_THREAD
&& !MICROPY_PY_THREAD_GIL.
Can be used where mp_obj_int_get_checked() will overflow due to the
sign-bit solely. This returns an mp_uint_t, so it also verifies the given
integer is not negative.
Currently implemented only for mpz configurations.
This function is called often and with immediate objects enabled it has
more cases, so optimise it for speed. With this optimisation the runtime
is now slightly faster with immediate objects enabled than with them
disabled.
This option (enabled by default for object representation A, B, C) makes
None/False/True objects immediate objects, ie they are no longer a concrete
object in ROM but are rather just values, eg None=0x6 for representation A.
Doing this saves a considerable amount of code size, due to these objects
being widely used:
bare-arm: -392 -0.591%
minimal x86: -252 -0.170% [incl +52(data)]
unix x64: -624 -0.125% [incl -128(data)]
unix nanbox: +0 +0.000%
stm32: -1940 -0.510% PYBV10
cc3200: -1216 -0.659%
esp8266: -404 -0.062% GENERIC
esp32: -732 -0.064% GENERIC[incl +48(data)]
nrf: -988 -0.675% pca10040
samd: -564 -0.556% ADAFRUIT_ITSYBITSY_M4_EXPRESS
Thanks go to @Jongy aka Yonatan Goldschmidt for the idea.
This commit adjusts the definition of qstr encoding in all object
representations by taking a single bit from the qstr space and using it to
distinguish between qstrs and a new kind of literal object: immediate
objects. In other words, the qstr space is divided in two pieces, one half
for qstrs and the other half for immediate objects.
There is still enough room for qstr values (29 bits in representation A on
a 32-bit architecture, and 19 bits in representation C) and the new
immediate objects can be used for things like None, False and True.
This moves the MICROPY_PORT_INIT_FUNC hook to the end of mp_init(), just
before MP_THREAD_GIL_ENTER(), so that everything (in particular the GIL
mutex) is intialized before the hook is called. MICROPY_PORT_DEINIT_FUNC
is also moved to be symmetric (but there is no functional change there).
If a port needs to perform initialisation earlier than
MICROPY_PORT_INIT_FUNC then it can do it before calling mp_init().
This commit adds backward-word, backward-kill-word, forward-word,
forward-kill-word sequences for the REPL, with bindings to Alt+F, Alt+B,
Alt+D and Alt+Backspace respectively. It is disabled by default and can be
enabled via MICROPY_REPL_EMACS_WORDS_MOVE.
Further enabling MICROPY_REPL_EMACS_EXTRA_WORDS_MOVE adds extra bindings
for these new sequences: Ctrl+Right, Ctrl+Left and Ctrl+W.
The features are enabled on unix micropython-coverage and micropython-dev.
Most types are in rodata/ROM, and mp_obj_base_t.type is a constant pointer,
so enforce this const-ness throughout the code base. If a type ever needs
to be modified (eg a user type) then a simple cast can be used.
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 71a3d6ec3b 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
4f9842ad80.
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).
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.
runtime0.h is part of the MicroPython ABI so it's simpler if it's
independent of config options, like MICROPY_PY_REVERSE_SPECIAL_METHODS.
What's effectively done here is to move MP_BINARY_OP_DIVMOD and
MP_BINARY_OP_CONTAINS up in the enum, then remove the #if
MICROPY_PY_REVERSE_SPECIAL_METHODS conditional.
Without this change .mpy files would need to have a feature flag for
MICROPY_PY_REVERSE_SPECIAL_METHODS (when embedding native code that uses
this enum).
This commit has no effect when MICROPY_PY_REVERSE_SPECIAL_METHODS is
disabled. With this option enabled this commit reduces code size by about
60 bytes.
For consistency with "umachine". Now that weak links are enabled
by default for built-in modules, this should be a no-op, but allows
extension of the bluetooth module by user code.
Also move registration of ubluetooth to objmodule rather than
port-specific.
This commit implements automatic module weak links for all built-in
modules, by searching for "ufoo" in the built-in module list if "foo"
cannot be found. This means that all modules named "ufoo" are always
available as "foo". Also, a port can no longer add any other weak links,
which makes strict the definition of a weak link.
It saves some code size (about 100-200 bytes) on ports that previously had
lots of weak links.
Some changes from the previous behaviour:
- It doesn't intern the non-u module names (eg "foo" is not interned),
which saves code size, but will mean that "import foo" creates a new qstr
(namely "foo") in RAM (unless the importing module is frozen).
- help('modules') no longer lists non-u module names, only the u-variants;
this reduces duplication in the help listing.
Weak links are effectively the same as having a set of symbolic links on
the filesystem that is searched last. So an "import foo" will search
built-in modules first, then all paths in sys.path, then weak links last,
importing "ufoo" if it exists. Thus a file called "foo.py" somewhere in
sys.path will still have precedence over the weak link of "foo" to "ufoo".
See issues: #1740, #4449, #5229, #5241.
When loading a manifest file, e.g. by include(), it will chdir first to the
directory of that manifest. This means that all file operations within a
manifest are relative to that manifest's location.
As a consequence of this, additional environment variables are needed to
find absolute paths, so the following are added: $(MPY_LIB_DIR),
$(PORT_DIR), $(BOARD_DIR). And rename $(MPY) to $(MPY_DIR) to be
consistent.
Existing manifests are updated to match.
This introduces a new build variable FROZEN_MANIFEST which can be set to a
manifest listing (written in Python) that describes the set of files to be
frozen in to the firmware.
Instead of encoding 4 zero bytes as placeholders for the simple_name and
source_file qstrs, and storing the qstrs after the bytecode, store the
qstrs at the location of these 4 bytes. This saves 4 bytes per bytecode
function stored in a .mpy file (for example lcd160cr.mpy drops by 232
bytes, 4x 58 functions). And resulting code size is slightly reduced on
ports that use this feature.
In which case place the native function prelude in a bytes object, linked
from the const_table of that function. An architecture should define
N_PRELUDE_AS_BYTES_OBJ to 1 before including py/emitnative.c to emit
correct machine code, then enable MICROPY_EMIT_NATIVE_PRELUDE_AS_BYTES_OBJ
so the runtime can correctly handle the prelude being in a bytes object.
Such that args/return regs for the parent are different to args/return regs
for child calls. For an architecture to use this feature it should define
the REG_PARENT_xxx macros before including py/emitnative.c.
Prior to this commit, when unwinding through an active finally the stack
was not being correctly popped/folded, which resulting in the VM crashing
for complicated unwinding of nested finallys.
This should be fixed with this commit, and more tests for return/break/
continue within a finally have been added to exercise this.
As of 7d58a197cf, `NULL` should no longer be
here because it's allowed (MP_QSTRnull took its place). This entry was
preventing the use of MP_QSTR_NULL to mean "NULL" (although this is not
currently used).
A blacklist should not be needed because it should be possible to intern
all strings.
Fixes issue #5140.
This check follows CPython's behaviour, because 'import *' always populates
the globals with the imported names, not locals.
Since it's safe to do this (doesn't lead to a crash or undefined behaviour)
the check is only enabled for MICROPY_CPYTHON_COMPAT.
Fixes issue #5121.
This patch compresses the second part of the bytecode prelude which
contains the source file name, function name, source-line-number mapping
and cell closure information. This part of the prelude now begins with a
single varible length unsigned integer which encodes 2 numbers, being the
byte-size of the following 2 sections in the header: the "source info
section" and the "closure section". After decoding this variable unsigned
integer it's possible to skip over one or both of these sections very
easily.
This scheme saves about 2 bytes for most functions compared to the original
format: one in the case that there are no closure cells, and one because
padding was eliminated.
The start of the bytecode prelude contains 6 numbers telling the amount of
stack needed for the Python values and exceptions, and the signature of the
function. Prior to this patch these numbers were all encoded one after the
other (2x variable unsigned integers, then 4x bytes), but using so many
bytes is unnecessary.
An entropy analysis of around 150,000 bytecode functions from the CPython
standard library showed that the optimal Shannon coding would need about
7.1 bits on average to encode these 6 numbers, compared to the existing 48
bits.
This patch attempts to get close to this optimal value by packing the 6
numbers into a single, varible-length unsigned integer via bit-wise
interleaving. The interleaving scheme is chosen to minimise the average
number of bytes needed, and at the same time keep the scheme simple enough
so it can be implemented without too much overhead in code size or speed.
The scheme requires about 10.5 bits on average to store the 6 numbers.
As a result most functions which originally took 6 bytes to encode these 6
numbers now need only 1 byte (in 80% of cases).
From the beginning of this project the RAISE_VARARGS opcode was named and
implemented following CPython, where it has an argument (to the opcode)
counting how many args the raise takes:
raise # 0 args (re-raise previous exception)
raise exc # 1 arg
raise exc from exc2 # 2 args (chained raise)
In the bytecode this operation therefore takes 2 bytes, one for
RAISE_VARARGS and one for the number of args.
This patch splits this opcode into 3, where each is now a single byte.
This reduces bytecode size by 1 byte for each use of raise. Every byte
counts! It also has the benefit of reducing code size (on all ports except
nanbox).
To make progress towards MicroPython supporting Python 3.5, adding the
matmul operator is important because it's a really "low level" part of the
language, being a new token and modifications to the grammar.
It doesn't make sense to make it configurable because 1) it would make the
grammar and lexer complicated/messy; 2) no other operators are
configurable; 3) it's not a feature that can be "dynamically plugged in"
via an import.
And matmul can be useful as a general purpose user-defined operator, it
doesn't have to be just for numpy use.
Based on work done by Jim Mussared.
Prior to this patch mp_opcode_format would calculate the incorrect size of
the MP_BC_UNWIND_JUMP opcode, missing the additional byte. But, because
opcodes below 0x10 are unused and treated as bytes in the .mpy load/save
and freezing code, this bug did not show any symptoms, since nested unwind
jumps would rarely (if ever) reach a depth of 16 (so the extra byte of this
opcode would be between 0x01 and 0x0f and be correctly loaded/saved/frozen
simply as an undefined opcode).
This patch fixes this bug by correctly accounting for the additional byte.
.
With this patch alignment is done relative to the start of the buffer that
is being unpacked, not the raw pointer value, as per CPython.
Fixes issue #3314.
This commit adds support for sys.settrace, allowing to install Python
handlers to trace execution of Python code. The interface follows CPython
as closely as possible. The feature is disabled by default and can be
enabled via MICROPY_PY_SYS_SETTRACE.
Prior to this patch the line number for a lambda would be "line 1" if the
body of the lambda contained only a simple expression (with no line number
stored in the parse node). Now the line number is always reported
correctly.
mp_compile no longer takes an emit_opt argument, rather this setting is now
provided by the global default_emit_opt variable.
Now, when -X emit=native is passed as a command-line option, the emitter
will be set for all compiled modules (included imports), not just the
top-level script.
In the future there could be a way to also set this variable from a script.
Fixes issue #4267.
With this patch exceptions that are re-raised have improved tracebacks
(less confusing, match CPython), and it makes re-raise slightly more
efficient (in time and RAM) because they no longer need to add a traceback.
Also general VM performance is not measurably affected.
Partially fixes issue #2928.
With this patch exception tracebacks that go through a finally are improved
(less confusing, match CPython), and it makes finally's slightly more
efficient (in time and RAM) because they no longer need to add a traceback.
Partially fixes issue #2928.
It's really an opcode that's not implemented, so use "opcode" instead of
"byte code". And remove the redundant "not implemented" text because that
is already implied by the exception type. There's no need to have a long
error message for an exception that is almost never encountered. Saves
about 20 bytes of code size on most ports.
Enabled via MICROPY_PY_URE_DEBUG, disabled by default (but enabled on unix
coverage build). This is a rarely used feature that costs a lot of code
(500-800 bytes flash). Debugging of regular expressions can be done
offline with other tools.
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.
As per PEP 485, this function appeared in for Python 3.5. Configured via
MICROPY_PY_MATH_ISCLOSE which is disabled by default, but enabled for the
ports which already have MICROPY_PY_MATH_SPECIAL_FUNCTIONS enabled.
Prior to this patch the amount of free space in an array (including
bytearray) was not being maintained correctly for the case of slice
assignment which changed the size of the array. Under certain cases (as
encoded in the new test) it was possible that the array could grow beyond
its allocated memory block and corrupt the heap.
Fixes issue #4127.
This patch implements a new sys.atexit function which registers a function
that is later executed when the main script ends. It is configurable via
MICROPY_PY_SYS_ATEXIT, disabled by default.
This is not compliant with CPython, rather it can be used to implement a
CPython compatible "atexit" module if desired (similar to how
sys.print_exception can be used to implement functionality of the
"traceback" module).
This patch adds a simple but powerful hook into the import system, in a
CPython compatible way, by allowing to override builtins.__import__.
This does introduce some overhead to all imports but it's minor:
- the dict lookup of __import__ is bypassed if there are no modifications
to the builtins module (which is the case at start up);
- imports are not performance critical, usually done just at the start of a
script;
- compared to how much work is done in an import, looking up a value in a
dict is a relatively small additional piece of work.
JSON requires that keys of objects be strings. CPython will therefore
automatically quote simple types (NoneType, bool, int, float) when they are
used directly as keys in JSON output. To prevent subtle bugs and emit
compliant JSON, MicroPython should at least test for such keys so they
aren't silently let through. Then doing the actual quoting is a similar
cost to raising an exception, so that's what is implemented by this patch.
Fixes issue #4790.
Behaviour was changed from stack to queue in
8977c7eb58, and this updates variable names
to match. Also updates other references (docs, error messages).
__clear_cache causes a compile error when using clang. Instead use
__builtin___clear_cache which is available under both gcc and clang.
Also replace tabs with spaces in this section of code (introduced by a
previous commit).
This fixes compiling for older architectures (e.g. armv5tej).
According to [1], the limit of R0-R7 for the STR and LDR instructions is
tied to the Thumb instruction set and not any specific processor
architectures.
[1]: http://www.keil.com/support/man/docs/armasm/armasm_dom1361289906890.htm
With both MICROPY_PERSISTENT_CODE_SAVE and MICROPY_PERSISTENT_CODE_LOAD
enabled the code fails to compile, due to undeclared 'n_obj'. If
MICROPY_EMIT_NATIVE is disabled there are more errors due to the use of
undefined fields in mp_raw_code_t.
This patch fixes such compilation by avoiding undefined fields.
MICROPY_EMIT_NATIVE was changed to MICROPY_EMIT_MACHINE_CODE in this file
to match the mp_raw_code_t definition.
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.
Instead of converting to a small-int at runtime this can be done at compile
time, then we only have a simple comparison during runtime. This reduces
code size on some ports (e.g -4 on qemu-arm, -52 on unix nanbox), and for
others at least doesn't increase code size.
mpy-cross uses MICROPY_DYNAMIC_COMPILER and MICROPY_EMIT_NATIVE but does
not actually need to execute native functions, and does not need
mp_fun_table. This commit makes it so mp_fun_table and all its entries are
not built when MICROPY_DYNAMIC_COMPILER is enabled, significantly reducing
the size of the mpy-cross executable and allowing it to be built on more
machines/OS's.
This ; make Windows compilation fail with GNU makefile 4.2.1. It was added
in 0dc85c9f86 as part of a shell if-
statement, but this if-statement was subsequently removed in
23a693ec2d so the semicolon is not needed.
The variable $(TOUCH) is initialized with the "touch" value in mkenv.mk
like for the other command line tools (rm, echo, cp, mkdir etc). With
this, for example, Windows users can specify the path of touch.exe.
The variable $(CAT) is initialised with the "cat" value in mkenv.mk like
for the other command line tools (rm, echo, cp, mkdir etc). With this,
for example, Windows users can specify the path of cat.exe.
Reuse the implementation for bytes since it works the same way regardless
of the underlying type. This method gets added for CPython compatibility
of bytearray, but to keep the code simple and small array.array now also
has a working decode method, which is non-standard but doesn't hurt.
This allows figuring out the number of bytes in the memoryview object as
len(memview) * memview.itemsize.
The feature is enabled via MICROPY_PY_BUILTINS_MEMORYVIEW_ITEMSIZE and is
disabled by default.
Prior to this commit, building the unix port with `DEBUG=1` and
`-finstrument-functions` the compilation would fail with an error like
"control reaches end of non-void function". This change fixes this by
removing the problematic "if (0)" branches. Not all branches affect
compilation, but they are all removed for consistency.
With this change, @micropython.asm_thumb functions will work on standard
ARM processors (that are in ARM state by default), in scripts and
precompiled .mpy files.
Addresses issue #4675.
This system makes it a lot easier to include external libraries as static,
native modules in MicroPython. Simply pass USER_C_MODULES (like
FROZEN_MPY_DIR) as a make parameter.
During make, makemoduledefs.py parses the current builds c files for
MP_REGISTER_MODULE(module_name, obj_module, enabled_define)
These are used to generate a header with the required entries for
"mp_rom_map_elem_t mp_builtin_module_table[]" in py/objmodule.c
This commit adds support for saving and loading .mpy files that contain
native code (native, viper and inline-asm). A lot of the ground work was
already done for this in the form of removing pointers from generated
native code. The changes here are mainly to link in qstr values to the
native code, and change the format of .mpy files to contain native code
blocks (possibly mixed with bytecode).
A top-level summary:
- @micropython.native, @micropython.viper and @micropython.asm_thumb/
asm_xtensa are now allowed in .py files when compiling to .mpy, and they
work transparently to the user.
- Entire .py files can be compiled to native via mpy-cross -X emit=native
and for the most part the generated .mpy files should work the same as
their bytecode version.
- The .mpy file format is changed to 1) specify in the header if the file
contains native code and if so the architecture (eg x86, ARMV7M, Xtensa);
2) for each function block the kind of code is specified (bytecode,
native, viper, asm).
- When native code is loaded from a .mpy file the native code must be
modified (in place) to link qstr values in, just like bytecode (see
py/persistentcode.c:arch_link_qstr() function).
In addition, this now defines a public, native ABI for dynamically loadable
native code generated by other languages, like C.
The new compile-time option is MICROPY_DEBUG_MP_OBJ_SENTINELS, disabled by
default. This is to allow finer control of whether this debugging feature
is enabled or not (because, for example, this setting must be the same for
mpy-cross and the MicroPython main code when using native code generation).
When encoded in the mpy file, if qstr <= QSTR_LAST_STATIC then store two
bytes: 0, static_qstr_id. Otherwise encode the qstr as usual (either with
string data or a reference into the qstr window).
Reduces mpy file size by about 5%.
Instead of emitting two bytes in the bytecode for where the linked qstr
should be written to, it is now replaced by the actual qstr data, or a
reference into the qstr window.
Reduces mpy file size by about 10%.
This is an implementation of a sliding qstr window used to reduce the
number of qstrs stored in a .mpy file. The window size is configured to 32
entries which takes a fixed 64 bytes (16-bits each) on the C stack when
loading/saving a .mpy file. It allows to remember the most recent 32 qstrs
so they don't need to be stored again in the .mpy file. The qstr window
uses a simple least-recently-used mechanism to discard the least recently
used qstr when the window overflows (similar to dictionary compression).
This scheme only needs a single pass to save/load the .mpy file.
Reduces mpy file size by about 25% with a window size of 32.
POP_BLOCK and POP_EXCEPT are now the same, and are always followed by a
JUMP. So this optimisation reduces code size, and RAM usage of bytecode by
two bytes for each try-except handler.
This patch fixes a bug in the VM when breaking within a try-finally. The
bug has to do with executing a break within the finally block of a
try-finally statement. For example:
def f():
for x in (1,):
print('a', x)
try:
raise Exception
finally:
print(1)
break
print('b', x)
f()
Currently in uPy the above code will print:
a 1
1
1
segmentation fault (core dumped) micropython
Not only is there a seg fault, but the "1" in the finally block is printed
twice. This is because when the VM executes a finally block it doesn't
really know if that block was executed due to a fall-through of the try (no
exception raised), or because an exception is active. In particular, for
nested finallys the VM has no idea which of the nested ones have active
exceptions and which are just fall-throughs. So when a break (or continue)
is executed it tries to unwind all of the finallys, when in fact only some
may be active.
It's questionable whether break (or return or continue) should be allowed
within a finally block, because they implicitly swallow any active
exception, but nevertheless it's allowed by CPython (although almost never
used in the standard library). And uPy should at least not crash in such a
case.
The solution here relies on the fact that exception and finally handlers
always appear in the bytecode after the try body.
Note: there was a similar bug with a return in a finally block, but that
was previously fixed in b735208403
Also, to make it possible for ports to provide their own lwipopts.h, the
default include directory of extmod/lwip-include is no longer added and
instead a port should now make sure the correct include directory is
included in the list (can still use extmod/lwip-include).
This optimisation eliminates the need to create a temporary normal dict.
The optimisation is enabled via MICROPY_COMP_CONST_LITERAL which is enabled
by default (although only has an effect if OrderdDict is enabled).
Thanks to @pfalcon for the initial idea and implementation.
All exceptions that unwind through the async-with must be caught and
BaseException is the top-level class, which includes Exception and others.
Fixes issue #4552.
As mentioned in #4450, `websocket` was experimental with a single intended
user, `webrepl`. Therefore, we'll make this change without a weak
link `websocket` -> `uwebsocket`.
This change makes it so that python3 is required by default to build
MicroPython. Python 2 can be used by specifying make PYTHON=python2.
This comes about due to a recent-ish change to PEP 394 that makes the
python command more optional than before (even with Python 2 installed);
see cd59ec03c8 (diff-1d22f7bd72cbc900670f058b1107d426)
Since the command python is no longer required to be provided by a
distribution we need to use either python2 or python3 as commands. And
python3 seems the obvious choice.
These macros could in principle be (inline) functions so it makes sense to
have them lower case, to match the other C API functions.
The remaining macros that are upper case are:
- MP_OBJ_TO_PTR, MP_OBJ_FROM_PTR
- MP_OBJ_NEW_SMALL_INT, MP_OBJ_SMALL_INT_VALUE
- MP_OBJ_NEW_QSTR, MP_OBJ_QSTR_VALUE
- MP_OBJ_FUN_MAKE_SIG
- MP_DECLARE_CONST_xxx
- MP_DEFINE_CONST_xxx
These must remain macros because they are used when defining const data (at
least, MP_OBJ_NEW_SMALL_INT is so it makes sense to have
MP_OBJ_SMALL_INT_VALUE also a macro).
For those macros that have been made lower case, compatibility macros are
provided for the old names so that users do not need to change their code
immediately.
Python defines warnings as belonging to categories, where category is a
warning type (descending from exception type). This is useful, as e.g.
allows to disable warnings selectively and provide user-defined warning
types. So, implement this in MicroPython, except that categories are
represented just with strings. However, enough hooks are left to implement
categories differently per-port (e.g. as types), without need to patch each
and every usage.
If MICROPY_PERSISTENT_CODE_LOAD or MICROPY_ENABLE_COMPILER are enabled then
code gets enabled that calls file reading functions which may be disabled
if no readers have been implemented.
To fix this, introduce a MICROPY_HAS_FILE_READER variable, which is
automatically set if MICROPY_READER_POSIX or MICROPY_READER_VFS is set but
can also be manually set if a custom reader is being implemented. Then
disable the file reading calls if this is not set.
For architectures where size_t is less than 32 bits (eg 16 bits) the args
must be casted to uint32_t so the left shift will work. For architectures
where size_t is greater than 32 bits (eg 64 bits) this new casting will not
lose any bits because the end result must anyway fit in a uint32_t.
Changes to the layout of the bytecode header meant that this debug code was
no longer compiling. This is now fixed and a new compile-time option is
introduced, MICROPY_DEBUG_VM_STACK_OVERFLOW, to turn on this feature (which
is disabled by default). This option is needed because more than one file
needs to cooperate to make this check work.
It's more robust to have the version defined statically in a header file,
rather than dynamically generating it via git using a git tag. In case
git doesn't exist, or a different source control tool is used, it's
important to still have the uPy version number available.
The older "bool has_finaliser" gets recast as GC_ALLOC_FLAG_HAS_FINALISER=1
so this is a backwards compatible change to the signature. Since bool gets
implicitly converted to 1 this patch doesn't include conversion of all
calls.
Both mp_type_array and mp_type_memoryview use the same object structure,
mp_obj_array_t, but for the case of memoryview, some fields, e.g. "free",
have different meaning. As the "free" field is also a bitfield, assume
that (anonymous) union can't be used here (for the concerns of possible
compatibility issues with wide array of toolchains), and just add a field
alias using a #define. As it's a define, it should be a selective
identifier, so use verbose "memview_offset" to avoid any clashes.
All 4 opcodes that can have caching bytes also have qstrs, so the test for
them must go in the qstr part of the code. The reason this incorrect
calculation of the opcode size did not lead to a bug is because the caching
byte is at the end of the opcode (byte, qstr, qstr, cache) and is always
0x00 when saving/loading, so was just treated as a single byte no-op
opcode. Hence these opcodes were being saved/loaded/decoded correctly.
Thanks to @malinah for finding the problem and providing the initial patch.
mp_obj_new_exception_msg() assumes that the message passed to it is in ROM
and so can use its data directly to create the string object for the
argument of the exception, saving RAM. At the same time, this approach
also makes sure that there is no attempt to format the message with printf,
which could lead to faults if the message contained % characters.
Fixes issue #3004.