Since the stride is specified in pixels, in a 4-bit horizontal format it
has to always be even, otherwise the computation is wrong and we can
write outside of the buffer sometimes.
Before this patch the mperrno.h file could be included and would silently
succeed with incorrect config settings, because mpconfig.h was not yet
included.
If constants (eg mp_const_none_obj) are placed in very high memory
locations that require 64-bits for the pointer then the assembler must be
able to emit instructions to move such pointers to one of the top 8
registers (ie r8-r15).
It's not used anywhere else in the VM loop, and clashes with (is shadowed
by) the n_state variable that's redeclared towards the end of the
mp_execute_bytecode function. Code size is unchanged.
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
Prior to this patch Servo numbers 1, 2, 3, 4 mapped to pins X3, X4, X1, X2
on PYBLITE which doesn't match the standard PYB mapping. This patch fixes
the mapping.
The default frozen modules are no longer included (but users can still
specify their own via FROZEN_MPY_DIR), complex numbers are disabled and so
are the native, viper and asm_thumb emitters. Users needing these features
can tune the build to disable other things.
Reasons to disable:
- the code is relatively robust so doesn't need full checking in the
main executable, and the coverage build is used for full testing
with assertions still enabled;
- reduces code size noticeably, by 27k for x86-64 and 20k for x86;
- allows to more easily track changes in code size, since assertions
can skew things.
