See issue #699.

See issue #699.

See issue #699.

Saves 24 bytes in bare-arm.

This helps compiler produce smaller code.  Saves 124 bytes on stmhal and
bare-arm.

Bytecode also needs a pass to compute the stack size.  This is because
the state size of the bytecode function is encoded as a variable uint,
so we must know the value of this uint before we encode it (otherwise
the size of the generated code changes from one pass to the next).

Having an entire pass for this seems wasteful (in time).  Alternative is
to allocate fixed space for the state size (would need 3-4 bytes to be
general, when 1 byte is usually sufficient) which uses a bit of extra
RAM per bytecode function, and makes the code less elegant in places
where this uint is encoded/decoded.

So, for now, opt for an extra pass.

Previously to this patch all constant string/bytes objects were
interned by the compiler, and this lead to crashes when the qstr was too
long (noticeable now that qstr length storage defaults to 1 byte).

With this patch, long string/bytes objects are never interned, and are
referenced directly as constant objects within generated code using
load_const_obj.

Compiler optimises lookup of module.CONST when enabled (an existing
feature).  Disabled by default; enabled for unix, windows, stmhal.
Costs about 100 bytes ROM on stmhal.

Addresses issue #1022.

This patch makes the MICROPY_PY_BUILTINS_SLICE compile-time option
fully disable the builtin slice operation (when set to 0).  This
includes removing the slice sytanx from the grammar.  Now, enabling
slice costs 4228 bytes on unix x64, and 1816 bytes on stmhal.

This patch makes MICROPY_PY_BUILTINS_SET compile-time option fully
disable the builtin set object (when set to 0).  This includes removing
set constructor/comprehension from the grammar, the compiler and the
emitters.  Now, enabling set costs 8168 bytes on unix x64, and 3576
bytes on stmhal.

This patch gives proper SyntaxError exceptions for bad global/nonlocal
declarations.  It also reduces code size: 304 bytes on unix x64, 132
bytes on stmhal.

You can now assign to the range end variable and the for-loop still
works correctly.  This fully addresses issue #565.

Also fixed a bug with the stack not being fully popped when breaking out
of an optimised for-loop (and it's actually impossible to write a test
for this case!).

Now you can assign to the range variable within the for loop and it will
still work.

Partially addresses issue #565.

Undefined behavior in C, needs explicit check.

Addresses issue #912.

This should pretty much resolve issue #50.

Addressing issue #50.

mp_parse_node_free now frees the memory associated with non-interned
strings.  And the parser calls mp_parse_node_free when discarding a
non-used node (such as a doc string).

Also, the compiler now frees the parse tree explicitly just before it
exits (as opposed to relying on the caller to do this).

Addresses issue #708 as best we can.

Towards resolving issue #50.

And move the MAP_ANON redefinition from py/asmx64.c to unix/alloc.c.

Optimises:
    if () -> if False
    if (x,...) -> if True
    if (a and b) -> if a and b

Viper functions can now be annotated with the type of their arguments
and return value.  Eg:

@micropython.viper
def f(x:int) -> int:
    return x + 1

Some small code clean-ups that result in about 80 bytes ROM saving for
stmhal.

But much smaller and memory-efficient. Uses Python builtin data structures
(dict, tuple, int) to describe structure layout.

See discussion in issue #50.

Native emitter can now compile try/except blocks using nlr_push/nlr_pop.
It probably only works for 1 level of exception handling.  It doesn't
work on Thumb (only x64).

Native emitter can also handle some additional op codes.

With this patch, 198 tests now pass using "-X emit=native" option to
micropython.

It defines types used by all other headers.

Fixes #691.