The nan-boxing representation has an extra 16-bits of space to store
small-int values, and making use of it allows to create and manipulate full
32-bit positive integers (ie up to 0xffffffff) without using the heap.
This patch simplifies the str creation API to favour the common case of
creating a str object that is not forced to be interned. To force
interning of a new str the new mp_obj_new_str_via_qstr function is added,
and should only be used if warranted.
Apart from simplifying the mp_obj_new_str function (and making it have the
same signature as mp_obj_new_bytes), this patch also reduces code size by a
bit (-16 bytes for bare-arm and roughly -40 bytes on the bare-metal archs).
These are now returned as "operation not supported" instead of raising
TypeError. In particular, this fixes equality for float vs incompatible
types, which now properly results in False instead of exception. This
also paves the road to support reverse operation (e.g. __radd__) with
float objects.
This is achieved by introducing mp_obj_get_float_maybe(), similar to
existing mp_obj_get_int_maybe().
NotImplemented means "try other fallbacks (like calling __rop__
instead of __op__) and if nothing works, raise TypeError". As
MicroPython doesn't implement any fallbacks, signal to raise
TypeError right away.
The unary-op/binary-op enums are already defined, and there are no
arithmetic tricks used with these types, so it makes sense to use the
correct enum type for arguments that take these values. It also reduces
code size quite a bit for nan-boxing builds.
The code conventions suggest using header guards, but do not define how
those should look like and instead point to existing files. However, not
all existing files follow the same scheme, sometimes omitting header guards
altogether, sometimes using non-standard names, making it easy to
accidentally pick a "wrong" example.
This commit ensures that all header files of the MicroPython project (that
were not simply copied from somewhere else) follow the same pattern, that
was already present in the majority of files, especially in the py folder.
The rules are as follows.
Naming convention:
* start with the words MICROPY_INCLUDED
* contain the full path to the file
* replace special characters with _
In addition, there are no empty lines before #ifndef, between #ifndef and
one empty line before #endif. #endif is followed by a comment containing
the name of the guard macro.
py/grammar.h cannot use header guards by design, since it has to be
included multiple times in a single C file. Several other files also do not
need header guards as they are only used internally and guaranteed to be
included only once:
* MICROPY_MPHALPORT_H
* mpconfigboard.h
* mpconfigport.h
* mpthreadport.h
* pin_defs_*.h
* qstrdefs*.h
The common cases for inheritance are 0 or 1 parent types, for both built-in
types (eg built-in exceptions) as well as user defined types. So it makes
sense to optimise the case of 1 parent type by storing just the type and
not a tuple of 1 value (that value being the single parent type).
This patch makes such an optimisation. Even though there is a bit more
code to handle the two cases (either a single type or a tuple with 2 or
more values) it helps reduce overall code size because it eliminates the
need to create a static tuple to hold single parents (eg for the built-in
exceptions). It also helps reduce RAM usage for user defined types that
only derive from a single parent.
Changes in code size (in bytes) due to this patch:
bare-arm: -16
minimal (x86): -176
unix (x86-64): -320
unix nanbox: -384
stmhal: -64
cc3200: -32
esp8266: -108
Hashing of float and complex numbers that are exact (real) integers should
return the same integer hash value as hashing the corresponding integer
value. Eg hash(1), hash(1.0) and hash(1+0j) should all be the same (this
is how Python is specified: if x==y then hash(x)==hash(y)).
This patch implements the simplest way of doing float/complex hashing by
just converting the value to int and returning that value.
The first memmove now copies less bytes in some cases (because len_adj <=
slice_len), and the memcpy is replaced with memmove to support the
possibility that dest and slice regions are overlapping.
This patch changes mp_uint_t to size_t for the len argument of the
following public facing C functions:
mp_obj_tuple_get
mp_obj_list_get
mp_obj_get_array
These functions take a pointer to the len argument (to be filled in by the
function) and callers of these functions should update their code so the
type of len is changed to size_t. For ports that don't use nan-boxing
there should be no change in generate code because the size of the type
remains the same (word sized), and in a lot of cases there won't even be a
compiler warning if the type remains as mp_uint_t.
The reason for this change is to standardise on the use of size_t for
variables that count memory (or memory related) sizes/lengths. It helps
builds that use nan-boxing.
It improves readability of code and reduces the chance to make a mistake.
This patch also fixes a bug with nan-boxing builds by rounding up the
calculation of the new NSLOTS variable, giving the correct number of slots
(being 4) even if mp_obj_t is larger than the native machine size.
Allows to iterate over the following without allocating on the heap:
- tuple
- list
- string, bytes
- bytearray, array
- dict (not dict.keys, dict.values, dict.items)
- set, frozenset
Allows to call the following without heap memory:
- all, any, min, max, sum
TODO: still need to allocate stack memory in bytecode for iter_buf.
The internal map/set functions now use size_t exclusively for computing
addresses. size_t is enough to reach all of available memory when
computing addresses so is the right type to use. In particular, for
nanbox builds it saves quite a bit of code size and RAM compared to the
original use of mp_uint_t (which is 64-bits on nanbox builds).
Builtin functions with a fixed number of arguments (0, 1, 2 or 3) are
quite common. Before this patch the wrapper for such a function cost
3 machine words. After this patch it only takes 2, which can reduce the
code size by quite a bit (and pays off even more, the more functions are
added). It also makes function dispatch slightly more efficient in CPU
usage, and furthermore reduces stack usage for these cases. On x86 and
Thumb archs the dispatch functions are now tail-call optimised by the
compiler.
The bare-arm port has its code size increase by 76 bytes, but stmhal drops
by 904 bytes. Stack usage by these builtin functions is decreased by 48
bytes on Thumb2 archs.
In order to have more fine-grained control over how builtin functions are
constructed, the MP_DECLARE_CONST_FUN_OBJ macros are made more specific,
with suffix of _0, _1, _2, _3, _VAR, _VAR_BETEEN or _KW. These names now
match the MP_DEFINE_CONST_FUN_OBJ macros.
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.
The C standard says that left-shifting a signed value (on the LHS of the
operator) is undefined. So we cast to an unsigned integer before the
shift. gcc does not issue a warning about this, but clang does.
They are sugar for marking function as generator, "yield from"
and pep492 python "semantically equivalents" respectively.
@dpgeorge was the original author of this patch, but @pohmelie made
changes to implement `async for` and `async with`.
The first argument to the type.make_new method is naturally a uPy type,
and all uses of this argument cast it directly to a pointer to a type
structure. So it makes sense to just have it a pointer to a type from
the very beginning (and a const pointer at that). This patch makes
such a change, and removes all unnecessary casting to/from mp_obj_t.
This patch changes the type signature of .make_new and .call object method
slots to use size_t for n_args and n_kw (was mp_uint_t. Makes code more
efficient when mp_uint_t is larger than a machine word. Doesn't affect
ports when size_t and mp_uint_t have the same size.
This allows to have single itertaor type for various internal iterator
types (save rodata space by not having repeating almost-empty type
structures). It works by looking "iternext" method stored in particular
object instance (should be first object field after "base").
To use, put the following in mpconfigport.h:
#define MICROPY_OBJ_REPR (MICROPY_OBJ_REPR_D)
#define MICROPY_FLOAT_IMPL (MICROPY_FLOAT_IMPL_DOUBLE)
typedef int64_t mp_int_t;
typedef uint64_t mp_uint_t;
#define UINT_FMT "%llu"
#define INT_FMT "%lld"
Currently does not work with native emitter enabled.
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.
This patch adds/subtracts a constant from the 30-bit float representation
so that str/qstr representations are favoured: they now have all the high
bits set to zero. This makes encoding/decoding qstr strings more
efficient (and they are used more often than floats, which are now
slightly less efficient to encode/decode).
Saves about 300 bytes of code space on Thumb 2 arch.
This new object representation puts floats into the object word instead
of on the heap, at the expense of reducing their precision to 30 bits.
It only makes sense when the word size is 32-bits.
The TimeoutError is useful for some modules, specially the the
socket module. TimeoutError can then be alised to socket.timeout
and then Python code can differentiate between socket.error and
socket.timeout.
mp_obj_get_int_truncated will raise a TypeError if the argument is not
an integral type. Use mp_obj_int_get_truncated only when you know the
argument is a small or big int.
Hashing is now done using mp_unary_op function with MP_UNARY_OP_HASH as
the operator argument. Hashing for int, str and bytes still go via
fast-path in mp_unary_op since they are the most common objects which
need to be hashed.
This lead to quite a bit of code cleanup, and should be more efficient
if anything. It saves 176 bytes code space on Thumb2, and 360 bytes on
x86.
The only loss is that the error message "unhashable type" is now the
more generic "unsupported type for __hash__".
Having NotImplemented as MP_OBJ_SENTINEL turned out to be problematic
(it needs to be checked for in a lot of places, otherwise it'll crash
as would pass MP_OBJ_IS_OBJ()), so made a proper singleton value like
Ellipsis, both of them sharing the same type.
This fixes a long standing problem that viper code generation gave
terrible error messages, and actually no errors on pyboard where
assertions are disabled.
Now all compile-time errors are raised as proper Python exceptions, and
are of type ViperTypeError.
Addresses issue #940.
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 simplifies the API for objects and reduces code size (by around 400
bytes on Thumb2, and around 2k on x86). Performance impact was measured
with Pystone score, but change was barely noticeable.
This patch gets full function argument passing working with native
emitter. Includes named args, keyword args, default args, var args
and var keyword args. Fully Python compliant.
It reuses the bytecode mp_setup_code_state function to do all the hard
work. This function is slightly adjusted to accommodate native calls,
and the native emitter is forced a bit to emit similar prelude and
code-info as bytecode.
mp_obj_t internal representation doesn't have to be a pointer to object,
it can be anything.
There's also a support for back-conversion in the form of MP_OBJ_UNCAST.
This is kind of optimization/status quo preserver to minimize patching the
existing code and avoid doing potentially expensive MP_OBJ_CAST over and
over. But then one may imagine implementations where MP_OBJ_UNCAST is very
expensive. But such implementations are unlikely interesting in practice.
Given that there's already support for "fixed table" maps, which are
essentially ordered maps, the implementation of OrderedDict just extends
"fixed table" maps by adding an "is ordered" flag and add/remove
operations, and reuses 95% of objdict code, just making methods tolerant
to both dict and OrderedDict.
Some things are missing so far, like CPython-compatible repr and comparison.
OrderedDict is Disabled by default; enabled on unix and stmhal ports.
This is rarely used feature which takes enough code to implement, so is
controlled by MICROPY_PY_ARRAY_SLICE_ASSIGN config setting, default off.
But otherwise it may be useful, as allows to update arbitrary-sized data
buffers in-place.
Slice is yet to implement, and actually, slice assignment implemented in
such a way that RHS of assignment should be array of the exact same item
typecode as LHS. CPython has it more relaxed, where RHS can be any sequence
of compatible types (e.g. it's possible to assign list of int's to a
bytearray slice).
Overall, when all "slice write" features are implemented, it may cost ~1KB
of code.
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.
Previous patch c38dc3ccc7 allowed any
object to be compared with any other, using pointer comparison for a
fallback. As such, existing code which checked for this case is no
longer needed.
This fixes conversion when float type has more mantissa bits than small int,
and float value has small exponent. This is for example the case of 32-bit
platform using doubles, and converting value of time.time(). Conversion of
floats with larg exponnet is still not handled correctly.
This patch adds a configuration option (MICROPY_CAN_OVERRIDE_BUILTINS)
which, when enabled, allows to override all names within the builtins
module. A builtins override dict is created the first time the user
assigns to a name in the builtins model, and then that dict is searched
first on subsequent lookups. Note that this implementation doesn't
allow deleting of names.
This patch also does some refactoring of builtins code, creating the
modbuiltins.c file.
Addresses issue #959.
