Now there is just one function to allocate a new vstr, namely vstr_new
(in addition to vstr_init etc). The caller of this function should know
what initial size to allocate for the buffer, or at least have some policy
or config option, instead of leaving it to a default (as it was before).
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.
This allows the mp_obj_t type to be configured to something other than a
pointer-sized primitive type.
This patch also includes additional changes to allow the code to compile
when sizeof(mp_uint_t) != sizeof(void*), such as using size_t instead of
mp_uint_t, and various casts.
Previous to this patch all interned strings lived in their own malloc'd
chunk. On average this wastes N/2 bytes per interned string, where N is
the number-of-bytes for a quanta of the memory allocator (16 bytes on 32
bit archs).
With this patch interned strings are concatenated into the same malloc'd
chunk when possible. Such chunks are enlarged inplace when possible,
and shrunk to fit when a new chunk is needed.
RAM savings with this patch are highly varied, but should always show an
improvement (unless only 3 or 4 strings are interned). New version
typically uses about 70% of previous memory for the qstr data, and can
lead to savings of around 10% of total memory footprint of a running
script.
Costs about 120 bytes code size on Thumb2 archs (depends on how many
calls to gc_realloc are made).
Previous to this patch the printing mechanism was a bit of a tangled
mess. This patch attempts to consolidate printing into one interface.
All (non-debug) printing now uses the mp_print* family of functions,
mainly mp_printf. All these functions take an mp_print_t structure as
their first argument, and this structure defines the printing backend
through the "print_strn" function of said structure.
Printing from the uPy core can reach the platform-defined print code via
two paths: either through mp_sys_stdout_obj (defined pert port) in
conjunction with mp_stream_write; or through the mp_plat_print structure
which uses the MP_PLAT_PRINT_STRN macro to define how string are printed
on the platform. The former is only used when MICROPY_PY_IO is defined.
With this new scheme printing is generally more efficient (less layers
to go through, less arguments to pass), and, given an mp_print_t*
structure, one can call mp_print_str for efficiency instead of
mp_printf("%s", ...). Code size is also reduced by around 200 bytes on
Thumb2 archs.
This cleans up vstr so that it's a pure "variable buffer", and the user
can decide whether they need to add a terminating null byte. In most
places where vstr is used, the vstr did not need to be null terminated
and so this patch saves code size, a tiny bit of RAM, and makes vstr
usage more efficient. When null termination is needed it must be
done explicitly using vstr_null_terminate.
With this patch str/bytes construction is streamlined. Always use a
vstr to build a str/bytes object. If the size is known beforehand then
use vstr_init_len to allocate only required memory. Otherwise use
vstr_init and the vstr will grow as needed. Then use
mp_obj_new_str_from_vstr to create a str/bytes object using the vstr
memory.
Saves code ROM: 68 bytes on stmhal, 108 bytes on bare-arm, and 336 bytes
on unix x64.
This patch allows to reuse vstr memory when creating str/bytes object.
This improves memory usage.
Also saves code ROM: 128 bytes on stmhal, 92 bytes on bare-arm, and 88
bytes on unix x64.
It seems most sensible to use size_t for measuring "number of bytes" in
malloc and vstr functions (since that's what size_t is for). We don't
use mp_uint_t because malloc and vstr are not Micro Python specific.
Parser shouldn't raise exceptions, so needs to check when memory
allocation fails. This patch does that for the initial set up of the
parser state.
Also, we now put the parser object on the stack. It's small enough to
go there instead of on the heap.
This partially addresses issue #558.
This will work if MICROPY_DEBUG_PRINTERS is defined, which is only for
unix/windows ports. This makes it convenient to user uPy normally, but
easily get bytecode dump on the spot if needed, without constant recompiles
back and forth.
TODO: Add more useful debug output, adjust verbosity level on which
specifically bytecode dump happens.
Blanket wide to all .c and .h files. Some files originating from ST are
difficult to deal with (license wise) so it was left out of those.
Also merged modpyb.h, modos.h, modstm.h and modtime.h in stmhal/.
Previously, a failed malloc/realloc would throw an exception, which was
not caught. I think it's better to keep the parser free from NLR
(exception throwing), hence this patch.
sys.path is not initialized by rt_init(), that's left for platform-specific
startup code. (For example, bare metal port may have some hardcoded defaults,
and let user change sys.path directly; while port for OS with environment
feature can take path from environment). If it's not explicitly initialized,
modules will be imported only from a current directory.
Damien George
Alex March
Paul Sokolovsky
Dave Hylands
David Steinberg
bvernoux
Chris Angelico
Emmanuel Blot
Kim Bauters
mux