With this patch all illegal assignments are reported as "can't assign to
expression". Before the patch there were special cases for a literal on
the LHS, and for augmented assignments (eg +=), but it seems a waste of
bytes (and there are lots of bytes used in error messages) to spend on
distinguishing such errors which a user will rarely encounter.
By removing the 'E' code from the operator token encoding mini-language the
tokenising can be simplified. The 'E' code was only used for the !=
operator which is now handled as a special case; the optimisations for the
general case more than make up for the addition of this single, special
case. Furthermore, the . and ... operators can be handled in the same way
as != which reduces the code size a little further.
This simplification also removes a "goto".
Changes in code size for this patch are (measured in bytes):
bare-arm: -48
minimal x86: -64
unix x86-64: -112
unix nanbox: -64
stmhal: -48
cc3200: -48
esp8266: -76
The self variable may be closed-over in the function, and in that case the
call to super() should load the contents of the closure cell using
LOAD_DEREF (before this patch it would just load the cell directly).
This class focuses on the timing sensitive parts of the protocol.
Everything else will be done by Python code.
This also establishes that its OK to back a nativeio class with a
bitbang implementation when no hardware acceleration exists. When
it does, then bitbangio should be used to explicitly bitbang a
protocol.
Previous to this patch, if the result of the round function overflowed a
small int, or was inf or nan, then a garbage value was returned. With
this patch the correct big-int is returned if necessary and exceptions are
raised for inf or nan.
The C nearbyint function has exactly the semantics that Python's round()
requires, whereas C's round() requires extra steps to handle rounding of
numbers half way between integers. So using nearbyint reduces code size
and potentially eliminates any source of errors in the handling of half-way
numbers.
Also, bare-metal implementations of nearbyint can be more efficient than
round, so further code size is saved (and efficiency improved).
nearbyint is provided in the C99 standard so it should be available on all
supported platforms.
Previous to this patch, if the result of the trunc/ceil/floor functions
overflowed a small int, or was inf or nan, then a garbage value was
returned. With this patch the correct big-int is returned if necessary,
and exceptions are raised for inf or nan.
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.
Instead of having the PlatformToolset property hardcoded to a specific
version just set it to the value of DefaultPlatformToolset: this gets
defined according to the commandline environment in which the build was
started.
Instead of just supporting VS2015 the project can now be built by any
version from VS2013 to VS2017 and normally future versions as well, without
quirks like VS asking whether you want to upgrade the project to the latest
version (as was the case when opening the project in VS2017) or not being
able to build at all (as was the case when opening the project in VS2013).
Also adjust the .gitignore file to ignore any artefacts from VS2017.
