Commit Graph

111 Commits

Author SHA1 Message Date
Damien George c7cb1dfcb9 py/parse: Fix macro evaluation by avoiding empty __VA_ARGS__.
Empty __VA_ARGS__ are not allowed in the C preprocessor so adjust the rule
arg offset calculation to not use them.  Also, some compilers (eg MSVC)
require an extra layer of macro expansion.
2017-12-29 13:44:26 +11:00
Damien George d3fbfa491f py/parse: Update debugging code to compile on 64-bit arch. 2017-12-29 00:13:36 +11:00
Damien George 0016a45368 py/parse: Compress rule pointer table to table of offsets.
This is the sixth and final patch in a series of patches to the parser that
aims to reduce code size by compressing the data corresponding to the rules
of the grammar.

Prior to this set of patches the rules were stored as rule_t structs with
rule_id, act and arg members.  And then there was a big table of pointers
which allowed to lookup the address of a rule_t struct given the id of that
rule.

The changes that have been made are:
- Breaking up of the rule_t struct into individual components, with each
  component in a separate array.
- Removal of the rule_id part of the struct because it's not needed.
- Put all the rule arg data in a big array.
- Change the table of pointers to rules to a table of offsets within the
  array of rule arg data.

The last point is what is done in this patch here and brings about the
biggest decreases in code size, because an array of pointers is now an
array of bytes.

Code size changes for the six patches combined is:

   bare-arm:  -644
minimal x86: -1856
   unix x64: -5408
unix nanbox: -2080
      stm32:  -720
    esp8266:  -812
     cc3200:  -712

For the change in parser performance: it was measured on pyboard that these
six patches combined gave an increase in script parse time of about 0.4%.
This is due to the slightly more complicated way of looking up the data for
a rule (since the 9th bit of the offset into the rule arg data table is
calculated with an if statement).  This is an acceptable increase in parse
time considering that parsing is only done once per script (if compiled on
the target).
2017-12-29 00:13:36 +11:00
Damien George c2c92ceefc py/parse: Remove rule_t struct because it's no longer needed. 2017-12-28 23:15:36 +11:00
Damien George 66d8885d85 py/parse: Pass rule_id to push_result_token, instead of passing rule_t*. 2017-12-28 23:12:10 +11:00
Damien George 815a8cd1ae py/parse: Pass rule_id to push_result_rule, instead of passing rule_t*.
Reduces code size by eliminating quite a few pointer dereferences.
2017-12-28 23:11:43 +11:00
Damien George 845511af25 py/parse: Break rule data into separate act and arg arrays.
Instead of each rule being stored in ROM as a struct with rule_id, act and
arg, the act and arg parts are now in separate arrays and the rule_id part
is removed because it's not needed.  This reduces code size, by roughly one
byte per grammar rule, around 150 bytes.
2017-12-28 23:09:49 +11:00
Damien George 1039c5e699 py/parse: Split out rule name from rule struct into separate array.
The rule name is only used for debugging, and this patch makes things a bit
cleaner by completely separating out the rule name from the rest of the
rule data.
2017-12-28 23:08:00 +11:00
Damien George 2759bec858 py: Extend nan-boxing config to have 47-bit small integers.
The nan-boxing representation has an extra 16-bits of space to store
small-int values, and making use of it allows to create and manipulate full
32-bit positive integers (ie up to 0xffffffff) without using the heap.
2017-12-11 22:39:12 +11:00
Damien George 1f1d5194d7 py/objstr: Make mp_obj_new_str_of_type check for existing interned qstr.
The function mp_obj_new_str_of_type is a general str object constructor
used in many places in the code to create either a str or bytes object.
When creating a str it should first check if the string data already exists
as an interned qstr, and if so then return the qstr object.  This patch
makes the function have such behaviour, which helps to reduce heap usage by
reusing existing interned data where possible.

The old behaviour of mp_obj_new_str_of_type (which didn't check for
existing interned data) is made available through the function
mp_obj_new_str_copy, but should only be used in very special cases.

One consequence of this patch is that the following expression is now True:

    'abc' is ' abc '.split()[0]
2017-11-16 13:53:04 +11:00
Damien George a3dc1b1957 all: Remove inclusion of internal py header files.
Header files that are considered internal to the py core and should not
normally be included directly are:
    py/nlr.h - internal nlr configuration and declarations
    py/bc0.h - contains bytecode macro definitions
    py/runtime0.h - contains basic runtime enums

Instead, the top-level header files to include are one of:
    py/obj.h - includes runtime0.h and defines everything to use the
        mp_obj_t type
    py/runtime.h - includes mpstate.h and hence nlr.h, obj.h, runtime0.h,
        and defines everything to use the general runtime support functions

Additional, specific headers (eg py/objlist.h) can be included if needed.
2017-10-04 12:37:50 +11:00
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
Damien George f615d82d5b py/parse: Simplify handling of errors by raising them directly.
The parser was originally written to work without raising any exceptions
and instead return an error value to the caller.  But it's now required
that a call to the parser be wrapped in an nlr handler, so we may as well
make use of that fact and simplify the parser so that it doesn't need to
keep track of any memory errors that it had.  The parser anyway explicitly
raises an exception at the end if there was an error.

This patch simplifies the parser by letting the underlying memory
allocation functions raise an exception if they fail to allocate any
memory.  And if there is an error parsing the "<id> = const(<val>)" pattern
then that also raises an exception right away instead of trying to recover
gracefully and then raise.
2017-02-24 14:56:37 +11:00
Damien George 5255255fb9 py: Create str/bytes objects in the parser, not the compiler.
Previous to this patch any non-interned str/bytes objects would create a
special parse node that held a copy of the str/bytes data.  Then in the
compiler this data would be turned into a str/bytes object.  This actually
lead to 2 copies of the data, one in the parse node and one in the object.
The parse node's copy of the data would be freed at the end of the compile
stage but nevertheless it meant that the peak memory usage of the
parse/compile stage was higher than it needed to be (by an amount equal to
the number of bytes in all the non-interned str/bytes objects).

This patch changes the behaviour so that str/bytes objects are created
directly in the parser and the object stored in a const-object parse node
(which already exists for bignum, float and complex const objects).  This
reduces peak RAM usage of the parse/compile stage, simplifies the parser
and compiler, and reduces code size by about 170 bytes on Thumb2 archs,
and by about 300 bytes on Xtensa archs.
2017-02-24 13:43:43 +11:00
Damien George 74f4d2c659 py/parse: Allow parser/compiler consts to be bignums.
This patch allows uPy consts to be bignums, eg:

    X = const(1 << 100)

The infrastructure for consts to be a bignum (rather than restricted to
small integers) has been in place for a while, ever since constant folding
was upgraded to allow bignums.  It just required a small change (in this
patch) to enable it.
2017-02-24 13:03:44 +11:00
Damien George 71019ae4f5 py/grammar: Group no-compile grammar rules together to shrink tables.
Grammar rules have 2 variants: ones that are attached to a specific
compile function which is called to compile that grammar node, and ones
that don't have a compile function and are instead just inspected to see
what form they take.

In the compiler there is a table of all grammar rules, with each entry
having a pointer to the associated compile function.  Those rules with no
compile function have a null pointer.  There are 120 such rules, so that's
120 words of essentially wasted code space.

By grouping together the compile vs no-compile rules we can put all the
no-compile rules at the end of the list of rules, and then we don't need
to store the null pointers.  We just have a truncated table and it's
guaranteed that when indexing this table we only index the first half,
the half with populated pointers.

This patch implements such a grouping by having a specific macro for the
compile vs no-compile grammar rules (DEF_RULE vs DEF_RULE_NC).  It saves
around 460 bytes of code on 32-bit archs.
2017-02-16 19:45:06 +11:00
Damien George 86e942309a py/parse: Refactor code to remove assert(0)'s.
This helps to improve code coverage.  Note that most of the changes in
this patch are just de-denting the cases of the switch statements.
2017-01-17 17:00:55 +11:00
Damien George 9b525134d1 py/parse: Add code to fold logical constants in or/and/not operations.
Adds about 200 bytes to the code size when constant folding is enabled.
2016-11-15 16:48:49 +11:00
Damien George ed9c93f0f1 py/parse: Make mp_parse_node_new_leaf an inline function.
It is split into 2 functions, one to make small ints and the other to make
a non-small-int leaf node.  This reduces code size by 32 bytes on
bare-arm, 64 bytes on unix (x64-64) and 144 bytes on stmhal.
2016-11-15 16:48:48 +11:00
Damien George b0cbfb0492 py/parse: Move function to check for const parse node to parse.[ch]. 2016-11-15 16:48:48 +11:00
Colin Hogben f9b6b37cf6 py: Fix wrong assumption that m_renew will not move if shrinking
In both parse.c and qstr.c, an internal chunking allocator tidies up
by calling m_renew to shrink an allocated chunk to the size used, and
assumes that the chunk will not move.  However, when MICROPY_ENABLE_GC
is false, m_renew calls the system realloc, which does not guarantee
this behaviour.  Environments where realloc may return a different
pointer include:

(1) mbed-os with MBED_HEAP_STATS_ENABLED (which adds a wrapper around
malloc & friends; this is where I was hit by the bug);

(2) valgrind on linux (how I diagnosed it).

The fix is to call m_renew_maybe with allow_move=false.
2016-11-02 23:15:41 +11:00
Damien George 6d310a5552 py/parse: Only replace constants that are standalone identifiers.
This fixes constant substitution so that only standalone identifiers are
replaced with their constant value (if they have one).  I.e. don't
replace NAME in expressions like obj.NAME or NAME = expr.
2016-09-23 17:23:16 +10:00
Damien George b1533c4366 py/parse: Treat constants that start with underscore as private.
Assignments of the form "_id = const(value)" are treated as private
(following a similar CPython convention) and code is no longer emitted
for the assignment to a global variable.

See issue #2111.
2016-06-06 17:28:32 +01:00
Damien George 3ff16ff52e py: Declare constant data as properly constant.
Otherwise some compilers (eg without optimisation) will put this read-only
data in RAM instead of ROM.
2016-05-20 12:46:20 +01:00
Damien George e36ff98c80 py/parse: Add uerrno to list of modules to look for constants in. 2016-05-10 23:30:39 +01:00
Damien George 0c1de1cdee py: Simplify "and" action within parser by making ident-rules explicit.
Most grammar rules can optimise to the identity if they only have a single
argument, saving a lot of RAM building the parse tree.  Previous to this
patch, whether a given grammar rule could be optimised was defined (mostly
implicitly) by a complicated set of logic rules.  With this patch the
definition is always specified explicitly by using "and_ident" in the rule
definition in the grammar.  This simplifies the logic of the parser,
making it a bit smaller and faster.  RAM usage in unaffected.
2016-04-14 13:49:23 +01:00
Damien George eacbd7aeba py: Fix constant folding and inline-asm to work with new async grammar. 2016-04-13 15:26:39 +01:00
Damien George 8d4d6731f5 py/parse: When looking up consts, check they exist before checking type. 2016-03-19 21:36:32 +00:00
Damien George d6c558c0aa py/parse: Use m_renew_maybe to ensure that memory is shrunk in-place.
The chunks of memory that the parser allocates contain parse nodes and
are pointed to from many places, so these chunks cannot be relocated
by the memory manager.  This patch makes it so that when a chunk is
shrunk to fit, it is not relocated.
2016-02-23 13:44:29 +00:00
Antonin ENFRUN efc971e8f9 py: unary_op enum type fix, and a cast to remove clang warning 2016-01-12 22:06:39 +01:00
Damien George 7dbf74c5b9 py/parse: Include unistd.h for ssize_t definition.
In some cases ssize_t is not defined by already included headers.
2016-01-08 13:42:00 +00:00
Damien George 22b2265053 py/parse: Improve constant folding to operate on small and big ints.
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.
2016-01-07 14:40:35 +00:00
Damien George 93b3726240 py/parse: Optimise away parse node that's just parenthesis around expr.
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.
2016-01-07 13:07:52 +00:00
Damien George dd5353a405 py: Add MICROPY_ENABLE_COMPILER and MICROPY_PY_BUILTINS_EVAL_EXEC opts.
MICROPY_ENABLE_COMPILER can be used to enable/disable the entire compiler,
which is useful when only loading of pre-compiled bytecode is supported.
It is enabled by default.

MICROPY_PY_BUILTINS_EVAL_EXEC controls support of eval and exec builtin
functions.  By default they are only included if MICROPY_ENABLE_COMPILER
is enabled.

Disabling both options saves about 40k of code size on 32-bit x86.
2015-12-18 12:35:44 +00:00
Damien George 16a6a47a7b py/parse: Replace mp_int_t/mp_uint_t with size_t etc, where appropriate. 2015-12-17 13:06:05 +00:00
Damien George b8cfb0d7b2 py: Add support for 64-bit NaN-boxing object model, on 32-bit machine.
To use, put the following in mpconfigport.h:

    #define MICROPY_OBJ_REPR (MICROPY_OBJ_REPR_D)
    #define MICROPY_FLOAT_IMPL (MICROPY_FLOAT_IMPL_DOUBLE)
    typedef int64_t mp_int_t;
    typedef uint64_t mp_uint_t;
    #define UINT_FMT "%llu"
    #define INT_FMT "%lld"

Currently does not work with native emitter enabled.
2015-11-29 14:25:36 +00:00
Damien George 999cedb90f py: Wrap all obj-ptr conversions in MP_OBJ_TO_PTR/MP_OBJ_FROM_PTR.
This allows the mp_obj_t type to be configured to something other than a
pointer-sized primitive type.

This patch also includes additional changes to allow the code to compile
when sizeof(mp_uint_t) != sizeof(void*), such as using size_t instead of
mp_uint_t, and various casts.
2015-11-29 14:25:35 +00:00
Damien George cbf7674025 py: Add MP_ROM_* macros and mp_rom_* types and use them. 2015-11-29 14:25:04 +00:00
Damien George 2c83894257 py: Implement default and star args for lambdas. 2015-11-17 14:00:14 +00:00
Damien George fdfcee7b1e py/parse: Make parser error handling cleaner, less spaghetti-like. 2015-10-12 12:59:18 +01:00
Damien George 64f2b213bb py: Move constant folding from compiler to parser.
It makes much more sense to do constant folding in the parser while the
parse tree is being built.  This eliminates the need to create parse
nodes that will just be folded away.  The code is slightly simpler and a
bit smaller as well.

Constant folding now has a configuration option,
MICROPY_COMP_CONST_FOLDING, which is enabled by default.
2015-10-12 12:58:45 +01:00
Damien George 366239b8b9 py/parse: Factor logic when creating parse node from and-rule. 2015-10-08 23:13:18 +01:00
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 65dc960e3b unix-cpy: Remove unix-cpy. It's no longer needed.
unix-cpy was originally written to get semantic equivalent with CPython
without writing functional tests.  When writing the initial
implementation of uPy it was a long way between lexer and functional
tests, so the half-way test was to make sure that the bytecode was
correct.  The idea was that if the uPy bytecode matched CPython 1-1 then
uPy would be proper Python if the bytecodes acted correctly.  And having
matching bytecode meant that it was less likely to miss some deep
subtlety in the Python semantics that would require an architectural
change later on.

But that is all history and it no longer makes sense to retain the
ability to output CPython bytecode, because:

1. It outputs CPython 3.3 compatible bytecode.  CPython's bytecode
changes from version to version, and seems to have changed quite a bit
in 3.5.  There's no point in changing the bytecode output to match
CPython anymore.

2. uPy and CPy do different optimisations to the bytecode which makes it
harder to match.

3. The bytecode tests are not run.  They were never part of Travis and
are not run locally anymore.

4. The EMIT_CPYTHON option needs a lot of extra source code which adds
heaps of noise, especially in compile.c.

5. Now that there is an extensive test suite (which tests functionality)
there is no need to match the bytecode.  Some very subtle behaviour is
tested with the test suite and passing these tests is a much better
way to stay Python-language compliant, rather than trying to match
CPy bytecode.
2015-08-17 12:51:26 +01:00
Damien George 96f0dd3cbc py/parse: Fix handling of empty input so it raises an exception. 2015-07-24 15:05:56 +00:00
Damien George fa7c61dfab py/parse: De-duplicate and simplify code for parser "or" rule. 2015-07-24 14:35:57 +00:00
Damien George ade9a05236 py: Improve allocation policy of qstr data.
Previous to this patch all interned strings lived in their own malloc'd
chunk.  On average this wastes N/2 bytes per interned string, where N is
the number-of-bytes for a quanta of the memory allocator (16 bytes on 32
bit archs).

With this patch interned strings are concatenated into the same malloc'd
chunk when possible.  Such chunks are enlarged inplace when possible,
and shrunk to fit when a new chunk is needed.

RAM savings with this patch are highly varied, but should always show an
improvement (unless only 3 or 4 strings are interned).  New version
typically uses about 70% of previous memory for the qstr data, and can
lead to savings of around 10% of total memory footprint of a running
script.

Costs about 120 bytes code size on Thumb2 archs (depends on how many
calls to gc_realloc are made).
2015-07-14 22:56:32 +01:00
Damien George 4735c45c51 py: Clean up some bits and pieces in parser, grammar. 2015-04-21 16:43:18 +00:00
nhtshot 5d323defe4 py: Update parse.c&mpconfig.h to reflect rename of mp_lexer_show_token.
This function is only used when DEBUG_PRINTERS and USE_RULE_NAME are
enabled.
2015-02-23 21:36:05 +00:00
Damien George dfe944c3e5 py: Expose compile.c:list_get as mp_parse_node_extract_list. 2015-02-13 02:29:46 +00:00