Commit Graph

22 Commits

Author SHA1 Message Date
Damien George
2283b6d68f py: Pass in address to compiled module instead of returning it.
This change makes it so the compiler and persistent code loader take a
mp_compiled_module_t* as their last argument, instead of returning this
struct.  This eliminates a duplicate context variable for all callers of
these functions (because the context is now stored in the
mp_compiled_module_t by the caller), and also eliminates any confusion
about which context to use after the mp_compile_to_raw_code or
mp_raw_code_load function returns (because there is now only one context,
that stored in mp_compiled_module_t.context).

Reduces code size by 16 bytes on ARM Cortex-based ports.

Signed-off-by: Damien George <damien@micropython.org>
2022-12-08 12:27:23 +11:00
Damien George
f2040bfc7e py: Rework bytecode and .mpy file format to be mostly static data.
Background: .mpy files are precompiled .py files, built using mpy-cross,
that contain compiled bytecode functions (and can also contain machine
code). The benefit of using an .mpy file over a .py file is that they are
faster to import and take less memory when importing.  They are also
smaller on disk.

But the real benefit of .mpy files comes when they are frozen into the
firmware.  This is done by loading the .mpy file during compilation of the
firmware and turning it into a set of big C data structures (the job of
mpy-tool.py), which are then compiled and downloaded into the ROM of a
device.  These C data structures can be executed in-place, ie directly from
ROM.  This makes importing even faster because there is very little to do,
and also means such frozen modules take up much less RAM (because their
bytecode stays in ROM).

The downside of frozen code is that it requires recompiling and reflashing
the entire firmware.  This can be a big barrier to entry, slows down
development time, and makes it harder to do OTA updates of frozen code
(because the whole firmware must be updated).

This commit attempts to solve this problem by providing a solution that
sits between loading .mpy files into RAM and freezing them into the
firmware.  The .mpy file format has been reworked so that it consists of
data and bytecode which is mostly static and ready to run in-place.  If
these new .mpy files are located in flash/ROM which is memory addressable,
the .mpy file can be executed (mostly) in-place.

With this approach there is still a small amount of unpacking and linking
of the .mpy file that needs to be done when it's imported, but it's still
much better than loading an .mpy from disk into RAM (although not as good
as freezing .mpy files into the firmware).

The main trick to make static .mpy files is to adjust the bytecode so any
qstrs that it references now go through a lookup table to convert from
local qstr number in the module to global qstr number in the firmware.
That means the bytecode does not need linking/rewriting of qstrs when it's
loaded.  Instead only a small qstr table needs to be built (and put in RAM)
at import time.  This means the bytecode itself is static/constant and can
be used directly if it's in addressable memory.  Also the qstr string data
in the .mpy file, and some constant object data, can be used directly.
Note that the qstr table is global to the module (ie not per function).

In more detail, in the VM what used to be (schematically):

    qst = DECODE_QSTR_VALUE;

is now (schematically):

    idx = DECODE_QSTR_INDEX;
    qst = qstr_table[idx];

That allows the bytecode to be fixed at compile time and not need
relinking/rewriting of the qstr values.  Only qstr_table needs to be linked
when the .mpy is loaded.

Incidentally, this helps to reduce the size of bytecode because what used
to be 2-byte qstr values in the bytecode are now (mostly) 1-byte indices.
If the module uses the same qstr more than two times then the bytecode is
smaller than before.

The following changes are measured for this commit compared to the
previous (the baseline):
- average 7%-9% reduction in size of .mpy files
- frozen code size is reduced by about 5%-7%
- importing .py files uses about 5% less RAM in total
- importing .mpy files uses about 4% less RAM in total
- importing .py and .mpy files takes about the same time as before

The qstr indirection in the bytecode has only a small impact on VM
performance.  For stm32 on PYBv1.0 the performance change of this commit
is:

diff of scores (higher is better)
N=100 M=100             baseline -> this-commit  diff      diff% (error%)
bm_chaos.py               371.07 ->  357.39 :  -13.68 =  -3.687% (+/-0.02%)
bm_fannkuch.py             78.72 ->   77.49 :   -1.23 =  -1.563% (+/-0.01%)
bm_fft.py                2591.73 -> 2539.28 :  -52.45 =  -2.024% (+/-0.00%)
bm_float.py              6034.93 -> 5908.30 : -126.63 =  -2.098% (+/-0.01%)
bm_hexiom.py               48.96 ->   47.93 :   -1.03 =  -2.104% (+/-0.00%)
bm_nqueens.py            4510.63 -> 4459.94 :  -50.69 =  -1.124% (+/-0.00%)
bm_pidigits.py            650.28 ->  644.96 :   -5.32 =  -0.818% (+/-0.23%)
core_import_mpy_multi.py  564.77 ->  581.49 :  +16.72 =  +2.960% (+/-0.01%)
core_import_mpy_single.py  68.67 ->   67.16 :   -1.51 =  -2.199% (+/-0.01%)
core_qstr.py               64.16 ->   64.12 :   -0.04 =  -0.062% (+/-0.00%)
core_yield_from.py        362.58 ->  354.50 :   -8.08 =  -2.228% (+/-0.00%)
misc_aes.py               429.69 ->  405.59 :  -24.10 =  -5.609% (+/-0.01%)
misc_mandel.py           3485.13 -> 3416.51 :  -68.62 =  -1.969% (+/-0.00%)
misc_pystone.py          2496.53 -> 2405.56 :  -90.97 =  -3.644% (+/-0.01%)
misc_raytrace.py          381.47 ->  374.01 :   -7.46 =  -1.956% (+/-0.01%)
viper_call0.py            576.73 ->  572.49 :   -4.24 =  -0.735% (+/-0.04%)
viper_call1a.py           550.37 ->  546.21 :   -4.16 =  -0.756% (+/-0.09%)
viper_call1b.py           438.23 ->  435.68 :   -2.55 =  -0.582% (+/-0.06%)
viper_call1c.py           442.84 ->  440.04 :   -2.80 =  -0.632% (+/-0.08%)
viper_call2a.py           536.31 ->  532.35 :   -3.96 =  -0.738% (+/-0.06%)
viper_call2b.py           382.34 ->  377.07 :   -5.27 =  -1.378% (+/-0.03%)

And for unix on x64:

diff of scores (higher is better)
N=2000 M=2000        baseline -> this-commit     diff      diff% (error%)
bm_chaos.py          13594.20 ->  13073.84 :  -520.36 =  -3.828% (+/-5.44%)
bm_fannkuch.py          60.63 ->     59.58 :    -1.05 =  -1.732% (+/-3.01%)
bm_fft.py           112009.15 -> 111603.32 :  -405.83 =  -0.362% (+/-4.03%)
bm_float.py         246202.55 -> 247923.81 : +1721.26 =  +0.699% (+/-2.79%)
bm_hexiom.py           615.65 ->    617.21 :    +1.56 =  +0.253% (+/-1.64%)
bm_nqueens.py       215807.95 -> 215600.96 :  -206.99 =  -0.096% (+/-3.52%)
bm_pidigits.py        8246.74 ->   8422.82 :  +176.08 =  +2.135% (+/-3.64%)
misc_aes.py          16133.00 ->  16452.74 :  +319.74 =  +1.982% (+/-1.50%)
misc_mandel.py      128146.69 -> 130796.43 : +2649.74 =  +2.068% (+/-3.18%)
misc_pystone.py      83811.49 ->  83124.85 :  -686.64 =  -0.819% (+/-1.03%)
misc_raytrace.py     21688.02 ->  21385.10 :  -302.92 =  -1.397% (+/-3.20%)

The code size change is (firmware with a lot of frozen code benefits the
most):

       bare-arm:  +396 +0.697%
    minimal x86: +1595 +0.979% [incl +32(data)]
       unix x64: +2408 +0.470% [incl +800(data)]
    unix nanbox: +1396 +0.309% [incl -96(data)]
          stm32: -1256 -0.318% PYBV10
         cc3200:  +288 +0.157%
        esp8266:  -260 -0.037% GENERIC
          esp32:  -216 -0.014% GENERIC[incl -1072(data)]
            nrf:  +116 +0.067% pca10040
            rp2:  -664 -0.135% PICO
           samd:  +844 +0.607% ADAFRUIT_ITSYBITSY_M4_EXPRESS

As part of this change the .mpy file format version is bumped to version 6.
And mpy-tool.py has been improved to provide a good visualisation of the
contents of .mpy files.

In summary: this commit changes the bytecode to use qstr indirection, and
reworks the .mpy file format to be simpler and allow .mpy files to be
executed in-place.  Performance is not impacted too much.  Eventually it
will be possible to store such .mpy files in a linear, read-only, memory-
mappable filesystem so they can be executed from flash/ROM.  This will
essentially be able to replace frozen code for most applications.

Signed-off-by: Damien George <damien@micropython.org>
2022-02-24 18:08:43 +11:00
Damien George
af20c2ead3 py: Add global default_emit_opt variable to make emit kind persistent.
mp_compile no longer takes an emit_opt argument, rather this setting is now
provided by the global default_emit_opt variable.

Now, when -X emit=native is passed as a command-line option, the emitter
will be set for all compiled modules (included imports), not just the
top-level script.

In the future there could be a way to also set this variable from a script.

Fixes issue #4267.
2019-08-28 12:47:58 +10:00
Damien George
3751512e9d py/emit: Move MP_EMIT_OPT_xxx enums from compile.h to emitglue.h. 2018-09-15 12:17:09 +10:00
Alexander Steffen
55f33240f3 all: Use the name MicroPython consistently in comments
There were several different spellings of MicroPython present in comments,
when there should be only one.
2017-07-31 18:35:40 +10:00
Alexander Steffen
299bc62586 all: Unify header guard usage.
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
2017-07-18 11:57:39 +10:00
Damien George
ad297a1950 py: Allow inline-assembler emitter to be generic.
This patch refactors some code so that it is easier to integrate new
inline assemblers for different architectures other than ARM Thumb.
2016-12-09 17:06:21 +11:00
Damien George
d4dba88236 py/compile: Add mp_compile_to_raw_code() to return raw code object.
This can then be passed to mp_raw_code_save_file to save a .mpy file.
2015-11-20 12:30:37 +00:00
Damien George
58e0f4ac50 py: Allocate parse nodes in chunks to reduce fragmentation and RAM use.
With this patch parse nodes are allocated sequentially in chunks.  This
reduces fragmentation of the heap and prevents waste at the end of
individually allocated parse nodes.

Saves roughly 20% of RAM during parse stage.
2015-10-02 00:11:11 +01:00
Damien George
0bfc7638ba py: Protect mp_parse and mp_compile with nlr push/pop block.
To enable parsing constants more efficiently, mp_parse should be allowed
to raise an exception, and mp_compile can already raise a MemoryError.
So these functions need to be protected by an nlr push/pop block.

This patch adds that feature in all places.  This allows to simplify how
mp_parse and mp_compile are called: they now raise an exception if they
have an error and so explicit checking is not needed anymore.
2015-02-07 18:33:58 +00:00
Paul Sokolovsky
8ab6f90674 py: Move to guarded includes for compile.h and related headers. 2014-12-27 16:12:17 +02:00
Damien George
c4d0868df1 py: Implement proper context save/restore for eval/exec; factor code.
This has benefits all round: code factoring for parse/compile/execute,
proper context save/restore for exec, allow to sepcify globals/locals
for eval, and reduced ROM usage by >100 bytes on stmhal and unix.

Also, the call to mp_parse_compile_execute is tail call optimised for
the import code, so it doesn't increase stack memory usage.
2014-10-05 20:13:34 +01:00
Damien George
52b5d76a6b py: Free non-interned strings in the parser when not needed.
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.
2014-09-23 15:31:56 +00:00
Damien George
96f137b24a py: Rename BYTE_CODE to BYTECODE (this was missed in previous rename). 2014-05-12 22:35:37 +01:00
Damien George
04b9147e15 Add license header to (almost) all files.
Blanket wide to all .c and .h files.  Some files originating from ST are
difficult to deal with (license wise) so it was left out of those.

Also merged modpyb.h, modos.h, modstm.h and modtime.h in stmhal/.
2014-05-03 23:27:38 +01:00
Damien George
78035b995f py, compiler: Clean up and compress scope/compile structures.
Convert int types to uint where sensible, and then to uint8_t or
uint16_t where possible to reduce RAM usage.
2014-04-09 12:27:39 +01:00
Damien George
65cad12d38 py: Add option to compiler to specify default code emitter.
Also add command line option to unix port to select emitter.
2014-04-06 11:48:15 +01:00
Damien George
08335004cf Add source file name and line number to error messages.
Byte code has a map from byte-code offset to source-code line number,
used to give better error messages.
2014-01-18 23:24:36 +00:00
Damien George
1fb031744f Change mp_compile so that it returns a function object for the module. 2014-01-03 14:22:03 +00:00
Damien
d99b05282d Change object representation from 1 big union to individual structs.
A big change.  Micro Python objects are allocated as individual structs
with the first element being a pointer to the type information (which
is itself an object).  This scheme follows CPython.  Much more flexible,
not necessarily slower, uses same heap memory, and can allocate objects
statically.

Also change name prefix, from py_ to mp_ (mp for Micro Python).
2013-12-21 18:17:45 +00:00
Damien
5ac1b2efbd Implement REPL. 2013-10-18 19:58:12 +01:00
Damien
429d71943d Initial commit. 2013-10-04 19:53:11 +01:00