Seedable and reproducible pseudo-random number generator. Implemented
functions are getrandbits(n) (n <= 32) and seed().
The algorithm used is Yasmarang by Ilya Levin:
http://www.literatecode.com/yasmarang
this allows python code to use property(lambda:..., doc=...) idiom.
named versions for the fget, fset and fdel arguments are left out in the
interest of saving space; they are rarely used and easy to enable when
actually needed.
a test case is included.
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.
Minimal support code for a Cortex-M CPU is added, along with set-up
code for an STM32F4xx MCU, including a UART for a REPL. Tested on
a pyboard. Code size is 77592 bytes.
Constant folding in the parser can now operate on big ints, whatever
their representation. This is now possible because the parser can create
parse nodes holding arbitrary objects. For the case of small ints the
folding is still efficient in RAM because the folded small int is stored
inplace in the parse node.
Adds 48 bytes to code size on Thumb2 architecture. Helps reduce heap
usage because more constants can be computed at compile time, leading to
a smaller parse tree, and most importantly means that the constants don't
have to be computed at runtime (perhaps more than once). Parser will now
be a little slower when folding due to calls to runtime to do the
arithmetic.
Before this patch, (x+y)*z would be parsed to a tree that contained a
redundant identity parse node corresponding to the parenthesis. With
this patch such nodes are optimised away, which reduces memory
requirements for expressions with parenthesis, and simplifies the
compiler because it doesn't need to handle this identity case.
A parenthesis parse node is still needed for tuples.
