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2016-02-17py/vm: Add macros to hook into various points in the VM.Damien George
These can be used to insert arbitrary checks, polling, etc into the VM. They are left general because the VM is a highly tuned loop and it should be up to a given port how that port wants to modify the VM internals. One common use would be to insert a polling check, but only done after a certain number of opcodes were executed, so as not to slow down the VM too much. For example: #define MICROPY_VM_HOOK_COUNT (30) #define MICROPY_VM_HOOK_INIT static uint vm_hook_divisor = MICROPY_VM_HOOK_COUNT #define MICROPY_VM_HOOK_POLL if (--vm_hook_divisor == 0) { \ vm_hook_divisor = MICROPY_VM_HOOK_COUNT; extern void vm_hook_function(void); vm_hook_function(); } #define MICROPY_VM_HOOK_LOOP MICROPY_VM_HOOK_POLL #define MICROPY_VM_HOOK_RETURN MICROPY_VM_HOOK_POLL
2016-02-01py/vm: Fix popping of exception block in UNWIND_JUMP opcode.Damien George
Fixes issue #1812.
2016-01-02py: Change exception traceback data to use size_t instead of mp_uint_t.Damien George
The traceback array stores qstrs and line numbers. qstrs are typed as size_t, and line numbers should safely fit in size_t as well.
2015-12-24py: Handle case of return within the finally block of try-finally.Damien George
Addresses issue #1636.
2015-12-17py: Fix MICROPY_STACKLESS mode to compile with MICROPY_OBJ_REPR_D.Damien George
2015-12-10py: Make UNARY_OP_NOT a first-class op, to agree with Py not semantics.Damien George
Fixes #1684 and makes "not" match Python semantics. The code is also simplified (the separate MP_BC_NOT opcode is removed) and the patch saves 68 bytes for bare-arm/ and 52 bytes for minimal/. Previously "not x" was implemented as !mp_unary_op(x, MP_UNARY_OP_BOOL), so any given object only needs to implement MP_UNARY_OP_BOOL (and the VM had a special opcode to do the ! bit). With this patch "not x" is implemented as mp_unary_op(x, MP_UNARY_OP_NOT), but this operation is caught at the start of mp_unary_op and dispatched as !mp_obj_is_true(x). mp_obj_is_true has special logic to test for truthness, and is the correct way to handle the not operation.
2015-11-29py: Wrap all obj-ptr conversions in MP_OBJ_TO_PTR/MP_OBJ_FROM_PTR.Damien George
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.
2015-11-13py: Add MICROPY_PERSISTENT_CODE so code can persist beyond the runtime.Damien George
Main changes when MICROPY_PERSISTENT_CODE is enabled are: - qstrs are encoded as 2-byte fixed width in the bytecode - all pointers are removed from bytecode and put in const_table (this includes const objects and raw code pointers) Ultimately this option will enable persistence for not just bytecode but also native code.
2015-10-15py: Fix with+for+return bug by popping for-iter when unwinding exc stack.Damien George
Addresses issue #1182.
2015-09-01vm: Handle "raise X from Y" statements the best way we can.Paul Sokolovsky
By issuing a warning that exception chaining is not supported, and ignoring "from Y" argument.
2015-06-25py: Remove mp_load_const_bytes and instead load precreated bytes object.Damien George
Previous to this patch each time a bytes object was referenced a new instance (with the same data) was created. With this patch a single bytes object is created in the compiler and is loaded directly at execute time as a true constant (similar to loading bignum and float objects). This saves on allocating RAM and means that bytes objects can now be used when the memory manager is locked (eg in interrupts). The MP_BC_LOAD_CONST_BYTES bytecode was removed as part of this. Generated bytecode is slightly larger due to storing a pointer to the bytes object instead of the qstr identifier. Code size is reduced by about 60 bytes on Thumb2 architectures.
2015-06-25py: Remove mp_load_const_str and replace uses with inlined version.Damien George
2015-06-13py: Add MP_BINARY_OP_DIVMOD to simplify and consolidate divmod builtin.Damien George
2015-05-12py: Convert hash API to use MP_UNARY_OP_HASH instead of ad-hoc function.Damien George
Hashing is now done using mp_unary_op function with MP_UNARY_OP_HASH as the operator argument. Hashing for int, str and bytes still go via fast-path in mp_unary_op since they are the most common objects which need to be hashed. This lead to quite a bit of code cleanup, and should be more efficient if anything. It saves 176 bytes code space on Thumb2, and 360 bytes on x86. The only loss is that the error message "unhashable type" is now the more generic "unsupported type for __hash__".
2015-05-11vm: Properly handle StopIteration raised in user instance iterator.Paul Sokolovsky
I.e. in bytecode Python functions.
2015-05-10vm: Null pointer test when checking for StopIteration optimizations.Paul Sokolovsky
When generator raises exception, it is automatically terminated (by setting its code_state.ip to 0), which interferes with this check. Triggered in particular by CPython's test_pep380.py.
2015-05-05py: Remove LOAD_CONST_ELLIPSIS bytecode, use LOAD_CONST_OBJ instead.Damien George
Ellipsis constant is rarely used so no point having an extra bytecode for it.
2015-04-26vm: On exiting except block, clear sys.exc_info() value.Paul Sokolovsky
This doesn't handle case fo enclosed except blocks, but once again, sys.exc_info() support is a workaround for software which uses it instead of properly catching exceptions via variable in except clause.
2015-04-25modsys: Add basic sys.exc_info() implementation.Paul Sokolovsky
The implementation is very basic and non-compliant and provided solely for CPython compatibility. The function itself is bad Python2 heritage, its usage is discouraged.
2015-04-24py: Modify bytecode "with" behaviour so it doesn't use any heap.Damien George
Before this patch a "with" block needed to create a bound method object on the heap for the __exit__ call. Now it doesn't because we use load_method instead of load_attr, and save the method+self on the stack.
2015-04-11py: Combine load_attr and store_attr type methods into one (attr).Damien George
This simplifies the API for objects and reduces code size (by around 400 bytes on Thumb2, and around 2k on x86). Performance impact was measured with Pystone score, but change was barely noticeable.
2015-04-09py: Adjust some spaces in code style/format, purely for consistency.Damien George
2015-04-09py: Fix msvc warning '*/ found outside of comment'stijn
Also prevents some of the weaker syntax parsers out there treating the whole '*/*const*/' part as a comment
2015-04-02py: Add finer configuration of static funcs when not in stackless mode.Damien George
Also rename call_args_t to mp_call_args_t.
2015-04-03vm: Support strict stackless mode, with proper exception reporting.Paul Sokolovsky
I.e. in this mode, C stack will never be used to call a Python function, but if there's no free heap for a call, it will be reported as RuntimeError (as expected), not MemoryError.
2015-04-03vm: Implement stackless for CALL_FUNCTION_VAR_KW & CALL_METHOD_VAR_KW.Paul Sokolovsky
2015-04-03vm: Stackless support for MP_BC_CALL_METHOD.Paul Sokolovsky
2015-04-03vm: If there's no heap to call function in stackless manner, call via C stack.Paul Sokolovsky
2015-04-03vm: Initial support for calling bytecode functions w/o C stack ("stackless").Paul Sokolovsky
2015-03-26py: Add optional support for descriptors' __get__ and __set__ methods.stijn
Disabled by default. Enabled on unix and windows ports.
2015-03-25py: Clean up some logic in VM to remove assert(0)'s.Damien George
Saves around 30 bytes code on Thumb2 archs.
2015-02-26py: Small optimisation of logic flow in BC_WITH_CLEANUP bytecode.Damien George
Slightly smaller code, and does not need to use C stack to save temporaries.
2015-02-10py: Reuse value stack in VM WITH_CLEANUP opcode to reduce C-stack size.Damien George
Saves 8 bytes C-stack on stmhal and 16 bytes on unix x86.
2015-02-08py: Parse big-int/float/imag constants directly in parser.Damien George
Previous to this patch, a big-int, float or imag constant was interned (made into a qstr) and then parsed at runtime to create an object each time it was needed. This is wasteful in RAM and not efficient. Now, these constants are parsed straight away in the parser and turned into objects. This allows constants with large numbers of digits (so addresses issue #1103) and takes us a step closer to #722.
2015-01-13py: Add load_const_obj to emitter, add LOAD_CONST_OBJ to bytecode.Damien George
This allows to directly load a Python object to the Python stack. See issue #722 for background.
2015-01-07py: Add option to cache map lookup results in bytecode.Damien George
This is a simple optimisation inspired by JITing technology: we cache in the bytecode (using 1 byte) the offset of the last successful lookup in a map. This allows us next time round to check in that location in the hash table (mp_map_t) for the desired entry, and if it's there use that entry straight away. Otherwise fallback to a normal map lookup. Works for LOAD_NAME, LOAD_GLOBAL, LOAD_ATTR and STORE_ATTR opcodes. On a few tests it gives >90% cache hit and greatly improves speed of code. Disabled by default. Enabled for unix and stmhal ports.
2015-01-07py: Put all global state together in state structures.Damien George
This patch consolidates all global variables in py/ core into one place, in a global structure. Root pointers are all located together to make GC tracing easier and more efficient.
2015-01-01py: Move to guarded includes, everywhere in py/ core.Damien George
Addresses issue #1022.
2014-12-29py: In VM, for selective ip saving, store 1 byte past last opcode.Damien George
This is for efficiency, so we don't need to subtract 1 from the ip before storing it to code_state->ip. It saves a lot of ROM bytes on unix and stmhal.
2014-12-28vm: Record exception ip only for instructions where exceptions may happen.Paul Sokolovsky
Mirroring ip to a volatile memory variable for each opcode is an expensive operation. For quite a lot of often executed opcodes like stack manipulation or jumps, exceptions cannot actually happen. So, record ip only for opcode where that's possible.
2014-12-22py: Reduce size of VM exception stack element by 1 machine word.Damien George
This optimisation reduces the VM exception stack element (mp_exc_stack_t) by 1 word, by using bit 1 of a pointer to store whether the opcode was a FINALLY or WITH opcode. This optimisation was pending, waiting for maturity of the exception handling code, which has now proven itself. Saves 1 machine word RAM for each exception (4->3 words per exception). Increases stmhal code by 4 bytes, and decreases unix x64 code by 32 bytes.
2014-12-12py: Fix label printing in showbc; print sp in vm trace.Damien George
2014-12-02py, vm: Make unum a local variable for each opcode that uses it.Damien George
This makes no change to the generated code, but it's now easier to understand since unum is not a "global" variable anymore.
2014-10-26py: Fix VM dispatch following a pending exception check.Damien George
2014-10-25py: Add mp_pending_exception global variable, for VM soft interrupt.Damien George
This allows to implement KeyboardInterrupt on unix, and a much safer ctrl-C in stmhal port. First ctrl-C is a soft one, with hope that VM will notice it; second ctrl-C is a hard one that kills anything (for both unix and stmhal). One needs to check for a pending exception in the VM only for jump opcodes. Others can't produce an infinite loop (infinite recursion is caught by stack check).
2014-10-25py: Compress load-int, load-fast, store-fast, unop, binop bytecodes.Damien George
There is a lot potential in compress bytecodes and make more use of the coding space. This patch introduces "multi" bytecodes which have their argument included in the bytecode (by addition). UNARY_OP and BINARY_OP now no longer take a 1 byte argument for the opcode. Rather, the opcode is included in the first byte itself. LOAD_FAST_[0,1,2] and STORE_FAST_[0,1,2] are removed in favour of their multi versions, which can take an argument between 0 and 15 inclusive. The majority of LOAD_FAST/STORE_FAST codes fit in this range and so this saves a byte for each of these. LOAD_CONST_SMALL_INT_MULTI is used to load small ints between -16 and 47 inclusive. Such ints are quite common and now only need 1 byte to store, and now have much faster decoding. In all this patch saves about 2% RAM for typically bytecode (1.8% on 64-bit test, 2.5% on pyboard test). It also reduces the binary size (because bytecodes are simplified) and doesn't harm performance.
2014-09-04py: Use variable length encoded uints in more places in bytecode.Damien George
Code-info size, block name, source name, n_state and n_exc_stack now use variable length encoded uints. This saves 7-9 bytes per bytecode function for most functions.
2014-08-26py: Fix line number printing for file with 1 line.Damien George
With a file with 1 line (and an error on that line), used to show the line as number 0. Now shows it correctly as line number 1. But, when line numbers are disabled, it now prints line number 1 for any line that has an error (instead of 0 as previously). This might end up being confusing, but requires extra RAM and/or hack logic to make it print something special in the case of no line numbers.
2014-07-31py: Improve encoding scheme for line-number to bytecode map.Damien George
Reduces by about a factor of 10 on average the amount of RAM needed to store the line-number to bytecode map in the bytecode prelude. Using CPython3.4's stdlib for statistics: previously, an average of 13 bytes were used per (bytecode offset, line-number offset) pair, and now with this improvement, that's down to 1.3 bytes on average. Large RAM usage before was due to some very large steps in line numbers, both from the start of the first line in a function way down in the file, and also functions that have big comments and/or big strings in them (both cases were significant). Although the savings are large on average for the CPython stdlib, it won't have such a big effect for small scripts used in embedded programming. Addresses issue #648.
2014-07-03Rename machine_(u)int_t to mp_(u)int_t.Damien George
See discussion in issue #50.