The system printf is no longer used by the core uPy code. Instead, the
platform print stream or DEBUG_printf is used. Using DEBUG_printf in the
showbc functions would mean that the code can't be tested by the test
suite, so use the normal output instead.
This patch also fixes parsing of bytecode-line-number mappings.
The vstr.had_error flag was a relic from the very early days which assumed
that the malloc functions (eg m_new, m_renew) returned NULL if they failed
to allocate. But that's no longer the case: these functions will raise an
exception if they fail.
Since it was impossible for had_error to be set, this patch introduces no
change in behaviour.
An alternative option would be to change the malloc calls to the _maybe
variants, which return NULL instead of raising, but then a lot of code
will need to explicitly check if the vstr had an error and raise if it
did.
The code-size savings for this patch are, in bytes: bare-arm:188,
minimal:456, unix(NDEBUG,x86-64):368, stmhal:228, esp8266:360.
With the previous patch combining 3 emit functions into 1, it now makes
sense to also combine the corresponding VM opcodes, which is what this
patch does. This eliminates 2 opcodes which simplifies the VM and reduces
code size, in bytes: bare-arm:44, minimal:64, unix(NDEBUG,x86-64):272,
stmhal:92, esp8266:200. Profiling (with a simple script that creates many
list/dict/set comprehensions) shows no measurable change in performance.
The 3 kinds of comprehensions are similar enough that merging their emit
functions reduces code size. Decreases in code size in bytes are:
bare-arm:24, minimal:96, unix(NDEBUG,x86-64):328, stmhal:80, esp8266:76.
bool(None) has a fast path in mp_obj_is_true so doesn't need to be
handled in none_unary_op. The only caveat is that subclassing may
bypass the mp_obj_is_true function, but actually you aren't allowed to
subclass classes that have singleton instances like NoneType (see
https://mail.python.org/pipermail/python-dev/2002-March/020822.html for
reference on this point).
py/makeqstrdefs.py declares that it works with python 2.6 however the
syntax used to initialise of a set with values was only added in python
2.7. This leads to build failures when the host system doesn't have
python 2.7 or newer.
Instead of using the new syntax pass a list of initial values through
set() to achieve the same result. This should work for python versions
from at least 2.6 onwards.
Helped-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Chris Packham <judge.packham@gmail.com>
Tested on a STM32F7DISCO at 216MHz. All tests generating code (inlineasm,
native, viper) now pass, except pybnative/while.py, but that's because
there is no LED(2).
This new config option allows to control whether MicroPython uses its own
internal printf or not (if not, an external one should be linked in).
Accompanying this new option is the inclusion of lib/utils/printf.c in the
core list of source files, so that ports no longer need to include it
themselves.
Arguments of an unknown type cannot be skipped and continuing to parse a
format string after encountering an unknown format specifier leads to
undefined behaviour. This patch helps to find use of unsupported formats.
The idea is that all ports can use these helper methods and only need to
provide initialisation of the SPI bus, as well as a single transfer
function. The coding pattern follows the stream protocol and helper
methods.
There can be stray pointers in memory blocks that are not properly zero'd
after allocation. This patch adds a new config option to always zero all
allocated memory (via gc_alloc and gc_realloc) and hence help to eliminate
stray pointers.
See issue #2195.
In current state `mp_get_stream_raise` assumes that `self_in` is an object
and always performs a pointer derefence which may cause a segfault.
This function shall throw an exception whenever `self_in` does not implement
a stream protocol, that includes qstr's and numbers.
fixes#2331
The machine_ptr_t type is long obsolete as the type of mp_obj_t is now
defined by the object representation, ie by MICROPY_OBJ_REPR. So just use
void* explicitly for the typedef of mp_obj_t.
If a port wants to use something different then they should define a new
object representation.
Only tuple, namedtuple and attrtuple use the tuple_cmp_helper function,
and they all have getiter=mp_obj_tuple_getiter, so the check here is only
to ensure that the self object is consistent. Hence use mp_check_self.
Checks for number of args removes where guaranteed by function descriptor,
self checking is replaced with mp_check_self(). In few cases, exception
is raised instead of assert.
Indended to replace raw asserts in bunch of files. Expands to empty
if MICROPY_BUILTIN_METHOD_CHECK_SELF_ARG is defined, otehrwise by
default still to assert, though a particular port may define it to
something else.
Introduce mp_raise_msg(), mp_raise_ValueError(), mp_raise_TypeError()
instead of previous pattern nlr_raise(mp_obj_new_exception_msg(...)).
Save few bytes on each call, which are many.
To filter out even prototypes of mp_stream_posix_*() functions, which
require POSIX types like ssize_t & off_t, which may be not available in
some ports.
Helpful when porting existing C libraries to MicroPython. abort()ing in
embedded environment isn't a good idea, so when compiling such library,
-Dabort=abort_ option can be given to redirect standard abort() to this
"safe" version.
Something like:
if foo == "bar":
will be always false if foo is b"bar". In CPython, warning is issued if
interpreter is started as "python3 -b". In MicroPython,
MICROPY_PY_STR_BYTES_CMP_WARN setting controls it.
Currently, MicroPython runs GC when it could not allocate a block of memory,
which happens when heap is exhausted. However, that policy can't work well
with "inifinity" heaps, e.g. backed by a virtual memory - there will be a
lot of swap thrashing long before VM will be exhausted. Instead, in such
cases "allocation threshold" policy is used: a GC is run after some number of
allocations have been made. Details vary, for example, number or total amount
of allocations can be used, threshold may be self-adjusting based on GC
outcome, etc.
This change implements a simple variant of such policy for MicroPython. Amount
of allocated memory so far is used for threshold, to make it useful to typical
finite-size, and small, heaps as used with MicroPython ports. And such GC policy
is indeed useful for such types of heaps too, as it allows to better control
fragmentation. For example, if a threshold is set to half size of heap, then
for an application which usually makes big number of small allocations, that
will (try to) keep half of heap memory in a nice defragmented state for an
occasional large allocation.
For an application which doesn't exhibit such behavior, there won't be any
visible effects, except for GC running more frequently, which however may
affect performance. To address this, the GC threshold is configurable, and
by default is off so far. It's configured with gc.threshold(amount_in_bytes)
call (can be queries without an argument).
3-arg form:
stream.write(data, offset, length)
2-arg form:
stream.write(data, length)
These allow efficient buffer writing without incurring extra memory
allocation for slicing or creating memoryview() object, what is
important for low-memory ports.
All arguments must be positional. It might be not so bad idea to standardize
on 3-arg form, but 2-arg case would need check and raising an exception
anyway then, so instead it was just made to work.
This follows source code/header file organization similar to few other
objects, and intended to be used only is special cases, where efficiency/
simplicity matters.
Previously, if there was chain of allocated blocks ending with the last
block of heap, it wasn't included in number of 1/2-block or max block
size stats.
Now only the bits that really need to be written in assembler are written
in it, otherwise C is used. This means that the assembler code no longer
needs to know about the global state structure which makes it much easier
to maintain.
GC_EXIT() can cause a pending thread (waiting on the mutex) to be
scheduled right away. This other thread may trigger a garbage
collection. If the pointer to the newly-allocated block (allocated by
the original thread) is not computed before the switch (so it's just left
as a block number) then the block will be wrongly reclaimed.
This patch makes sure the pointer is computed before allowing any thread
switch to occur.
By using a single, global mutex, all memory-related functions (alloc,
free, realloc, collect, etc) are made thread safe. This means that only
one thread can be in such a function at any one time.
This allows to define an abstract base class which would translate
C-level protocol to Python method calls, and any subclass inheriting
from it will support this feature. This in particular actually enables
recently introduced machine.PinBase class.
Allows to translate C-level pin API to Python-level pin API. In other
words, allows to implement a pin class and Python which will be usable
for efficient C-coded algorithms, like bitbanging SPI/I2C, time_pulse,
etc.
That's arbitrary restriction, in case of embedding, a source file path may
be absolute. For the purpose of filtering out system includes, checking
for ".c" suffix is enough.
Assignments of the form "_id = const(value)" are treated as private
(following a similar CPython convention) and code is no longer emitted
for the assignment to a global variable.
See issue #2111.
Using usual method of virtual method tables. Single virtual method,
ioctl, is defined currently for all operations. This universal and
extensible vtable-based method is also defined as a default MPHAL
GPIO implementation, but a specific port may override it with its
own implementation (e.g. close-ended, but very efficient, e.g. avoiding
virtual method dispatch).
Disabled by default, enabled in unix port. Need for this method easily
pops up when working with text UI/reporting, and coding workalike
manually again and again counter-productive.
Now frozen modules is treated just as a kind of VFS, and all operations
performed on it correspond to operations on normal filesystem. This allows
to support packages properly, and potentially also data files.
This change also have changes to rework frozen bytecode modules support to
use the same framework, but it's not finished (and actually may not work,
as older adhox handling of any type of frozen modules is removed).
Both read and write operations support variants where either a) a single
call is made to the undelying stream implementation and returned buffer
length may be less than requested, or b) calls are repeated until requested
amount of data is collected, shorter amount is returned only in case of
EOF or error.
These operations are available from the level of C support functions to be
used by other C modules to implementations of Python methods to be used in
user-facing objects.
The rationale of these changes is to allow to write concise and robust
code to work with *blocking* streams of types prone to short reads, like
serial interfaces and sockets. Particular object types may select "exact"
vs "once" types of methods depending on their needs. E.g., for sockets,
revc() and send() methods continue to be "once", while read() and write()
thus converted to "exactly" versions.
These changes don't affect non-blocking handling, e.g. trying "exact"
method on the non-blocking socket will return as much data as available
without blocking. No data available is continued to be signaled as None
return value to read() and write().
From the point of view of CPython compatibility, this model is a cross
between its io.RawIOBase and io.BufferedIOBase abstract classes. For
blocking streams, it works as io.BufferedIOBase model (guaranteeing
lack of short reads/writes), while for non-blocking - as io.RawIOBase,
returning None in case of lack of data (instead of raising expensive
exception, as required by io.BufferedIOBase). Such a cross-behavior
should be optimal for MicroPython needs.
Address printed was truncated anyway and in general confusing to outsider.
A line which dumps it is still left in the source, commented, for peculiar
cases when it may be needed (e.g. when running under debugger).
In some compliation enviroments (e.g. mbed online compiler) with
strict standards compliance, <math.h> does not define constants such
as M_PI. Provide fallback definitions of M_E and M_PI where needed.
If an OSError is raised with an integer argument, and that integer
corresponds to an errno, then the string for the errno is used as the
argument to the exception, instead of the integer. Only works if
the uerrno module is enabled.
These are typical consumers of large chunks of memory, so it's useful to
see at least their number (how much memory isn't clearly shown, as the data
for these objects is allocated elsewhere).
Effect measured on esp8266 port:
Before:
>>> pystone_lowmem.main(10000)
Pystone(1.2) time for 10000 passes = 44214 ms
This machine benchmarks at 226 pystones/second
>>> pystone_lowmem.main(10000)
Pystone(1.2) time for 10000 passes = 44246 ms
This machine benchmarks at 226 pystones/second
After:
>>> pystone_lowmem.main(10000)
Pystone(1.2) time for 10000 passes = 44343ms
This machine benchmarks at 225 pystones/second
>>> pystone_lowmem.main(10000)
Pystone(1.2) time for 10000 passes = 44376ms
This machine benchmarks at 225 pystones/second
vstr_null_terminated_str is almost certainly a vstr finalization operation,
so it should add the requested NUL byte, and not try to pre-allocate more.
The previous implementation could actually allocate double of the buffer
size.
Previous to this patch bignum division and modulo would temporarily
modify the RHS argument to the operation (eg x/y would modify y), but on
return the RHS would be restored to its original value. This is not
allowed because arguments to binary operations are const, and in
particular might live in ROM. The modification was to normalise the arg
(and then unnormalise before returning), and this patch makes it so the
normalisation is done on the fly and the arg is now accessed as read-only.
This change doesn't increase the order complexity of the operation, and
actually reduces code size.
