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096e967aad
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Paul Sokolovsky 096e967aad Revert "py/nlr: Factor out common NLR code to generic functions." 
This reverts commit 6a3a742a6c.

The above commit has number of faults starting from the motivation down
to the actual implementation.

1. Faulty implementation.

The original code contained functions like:

NORETURN void nlr_jump(void *val) {
    nlr_buf_t **top_ptr = &MP_STATE_THREAD(nlr_top);
    nlr_buf_t *top = *top_ptr;
...
     __asm volatile (
    "mov    %0, %%edx           \n" // %edx points to nlr_buf
    "mov    28(%%edx), %%esi    \n" // load saved %esi
    "mov    24(%%edx), %%edi    \n" // load saved %edi
    "mov    20(%%edx), %%ebx    \n" // load saved %ebx
    "mov    16(%%edx), %%esp    \n" // load saved %esp
    "mov    12(%%edx), %%ebp    \n" // load saved %ebp
    "mov    8(%%edx), %%eax     \n" // load saved %eip
    "mov    %%eax, (%%esp)      \n" // store saved %eip to stack
    "xor    %%eax, %%eax        \n" // clear return register
    "inc    %%al                \n" // increase to make 1, non-local return
     "ret                        \n" // return
    :                               // output operands
    : "r"(top)                      // input operands
    :                               // clobbered registers
     );
}

Which clearly stated that C-level variable should be a parameter of the
assembly, whcih then moved it into correct register.

Whereas now it's:

NORETURN void nlr_jump_tail(nlr_buf_t *top) {
    (void)top;

    __asm volatile (
    "mov    28(%edx), %esi      \n" // load saved %esi
    "mov    24(%edx), %edi      \n" // load saved %edi
    "mov    20(%edx), %ebx      \n" // load saved %ebx
    "mov    16(%edx), %esp      \n" // load saved %esp
    "mov    12(%edx), %ebp      \n" // load saved %ebp
    "mov    8(%edx), %eax       \n" // load saved %eip
    "mov    %eax, (%esp)        \n" // store saved %eip to stack
    "xor    %eax, %eax          \n" // clear return register
    "inc    %al                 \n" // increase to make 1, non-local return
    "ret                        \n" // return
    );

    for (;;); // needed to silence compiler warning
}

Which just tries to perform operations on a completely random register (edx
in this case). The outcome is the expected: saving the pure random luck of
the compiler putting the right value in the random register above, there's
a crash.

2. Non-critical assessment.

The original commit message says "There is a small overhead introduced
(typically 1 machine instruction)". That machine instruction is a call
if a compiler doesn't perform tail optimization (happens regularly), and
it's 1 instruction only with the broken code shown above, fixing it
requires adding more. With inefficiencies already presented in the NLR
code, the overhead becomes "considerable" (several times more than 1%),
not "small".

The commit message also says "This eliminates duplicated code.". An
obvious way to eliminate duplication would be to factor out common code
to macros, not introduce overhead and breakage like above.

3. Faulty motivation.

All this started with a report of warnings/errors happening for a niche
compiler. It could have been solved in one the direct ways: a) fixing it
just for affected compiler(s); b) rewriting it in proper assembly (like
it was before BTW); c) by not doing anything at all, MICROPY_NLR_SETJMP
exists exactly to address minor-impact cases like thar (where a) or b) are
not applicable). Instead, a backwards "solution" was put forward, leading
to all the issues above.

The best action thus appears to be revert and rework, not trying to work
around what went haywire in the first place.
2017-12-26 19:27:58 +02:00
..
argcheck.c py/argcheck: Remove #if guard around terse error message helper func. 2017-10-19 18:57:26 +11:00
asmarm.c all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
asmarm.h py/emitnative: Clean up asm macro names so they have dest as first arg. 2017-11-15 11:46:49 +11:00
asmbase.c py/asmbase: Revert removal of clearing of label offsets for native emit. 2017-12-08 19:07:00 +11:00
asmbase.h py/asm: Remove need for dummy_data when doing initial assembler passes. 2016-12-09 22:50:58 +11:00
asmthumb.c py/asmthumb: Use existing macro to properly clear the D-cache. 2017-08-23 11:32:27 +10:00
asmthumb.h py/emitnative: Clean up asm macro names so they have dest as first arg. 2017-11-15 11:46:49 +11:00
asmx64.c all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
asmx64.h py/emitnative: Clean up asm macro names so they have dest as first arg. 2017-11-15 11:46:49 +11:00
asmx86.c all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
asmx86.h py/emitnative: Clean up asm macro names so they have dest as first arg. 2017-11-15 11:46:49 +11:00
asmxtensa.c py/asm: Remove need for dummy_data when doing initial assembler passes. 2016-12-09 22:50:58 +11:00
asmxtensa.h py/emitnative: Clean up asm macro names so they have dest as first arg. 2017-11-15 11:46:49 +11:00
bc0.h py: Clean up unary and binary enum list to keep groups together. 2017-10-05 10:49:44 +11:00
bc.c py/bc: Update opcode_format_table to match the bytecode. 2017-10-10 10:37:38 +11:00
bc.h all: Remove inclusion of internal py header files. 2017-10-04 12:37:50 +11:00
binary.c py/objstr: Remove "make_qstr_if_not_already" arg from mp_obj_new_str. 2017-11-16 13:17:51 +11:00
binary.h py/binary: Change internal bytearray typecode from 0 to 1. 2017-08-17 16:19:35 +10:00
builtin.h py/builtinhelp: Change signature of help text var from pointer to array. 2017-09-12 16:03:52 +10:00
builtinevex.c all: Remove inclusion of internal py header files. 2017-10-04 12:37:50 +11:00
builtinhelp.c py/objstr: Remove "make_qstr_if_not_already" arg from mp_obj_new_str. 2017-11-16 13:17:51 +11:00
builtinimport.c py/builtinimport: Call __init__ for modules imported via a weak link. 2017-12-13 14:48:53 +11:00
compile.c py: Convert all uses of alloca() to use new scoped allocation API. 2017-12-11 13:49:09 +11:00
compile.h all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
emit.h all: Remove inclusion of internal py header files. 2017-10-04 12:37:50 +11:00
emitbc.c py/{emitbc,asmbase}: Only clear emit labels to -1 when in debug mode. 2017-12-08 18:23:23 +11:00
emitcommon.c all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
emitglue.c py: Add verbose debug compile-time flag MICROPY_DEBUG_VERBOSE. 2017-08-15 11:53:36 +10:00
emitglue.h py/emitglue: Change type of bit-field to explicitly unsigned mp_uint_t. 2017-12-15 10:21:10 +11:00
emitinlinethumb.c all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
emitinlinextensa.c py/emitinline: Move common code for end of final pass to compiler. 2016-12-09 21:23:17 +11:00
emitnative.c py/emitnative: Clean up asm macro names so they have dest as first arg. 2017-11-15 11:46:49 +11:00
formatfloat.c py/formatfloat: Use standard isinf, isnan funcs instead of custom ones. 2017-10-10 16:27:54 +11:00
formatfloat.h all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
frozenmod.c all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
frozenmod.h all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
gc.c py: Introduce a Python stack for scoped allocation. 2017-12-11 13:49:09 +11:00
gc.h all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
grammar.h all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
lexer.c all: Remove inclusion of internal py header files. 2017-10-04 12:37:50 +11:00
lexer.h all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
makeqstrdata.py py/objtype: Fit qstrs for special methods in byte type. 2017-10-21 11:06:32 +03:00
makeqstrdefs.py py/makeqstrdefs.py: Make script run correctly with Python 2.6. 2017-06-09 13:42:13 +10:00
makeversionhdr.py py/makeversionhdr.py: Update to parse new release line in docs/conf.py. 2017-07-04 22:37:41 +10:00
malloc.c py/malloc: Remove unneeded code checking m_malloc return value. 2017-12-20 16:55:42 +11:00
map.c py/map: Don't include ordered-dict mutating code when not needed. 2017-12-19 13:37:15 +11:00
misc.h py/misc.h: Add m_new_obj_var_with_finaliser(). 2017-12-04 11:05:49 +02:00
mkenv.mk py/mkenv.mk: Use $(PYTHON) consistently when calling Python tools. 2017-11-15 11:56:58 +11:00
mkrules.mk py/mkrules.mk: Add "clean-frozen" target to clean frozen script/modules dir. 2017-12-10 01:05:29 +02:00
modarray.c all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
modbuiltins.c py/modbuiltins: Use standard arg-parsing helper func for builtin print. 2017-12-05 12:14:57 +11:00
modcmath.c py: Change obsolete "///" comment formatting to normal comments. 2017-08-30 21:02:00 +10:00
modcollections.c all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
modgc.c py: Change obsolete "///" comment formatting to normal comments. 2017-08-30 21:02:00 +10:00
modio.c py/modio: Use correct config macro to enable resource_stream function. 2017-12-19 16:59:08 +11:00
modmath.c py/modmath: Convert log2 macro into a function. 2017-10-10 16:01:04 +11:00
modmicropython.c py: Introduce a Python stack for scoped allocation. 2017-12-11 13:49:09 +11:00
modstruct.c py/modstruct: Check and prevent buffer-write overflow in struct packing. 2017-09-01 11:11:09 +10:00
modsys.c all: Remove inclusion of internal py header files. 2017-10-04 12:37:50 +11:00
modthread.c py: Introduce a Python stack for scoped allocation. 2017-12-11 13:49:09 +11:00
moduerrno.c py/moduerrno: Make list of errno codes configurable. 2017-02-22 12:58:11 +11:00
mpconfig.h py/objgenerator: Allow to pend an exception for next execution. 2017-12-15 20:20:36 +02:00
mperrno.h py/mperrno: Allow mperrno.h to be correctly included before other hdrs. 2017-07-24 18:41:24 +10:00
mphal.h all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
mpprint.c py/mpprint: Fix "%x" vs "%X" regression introduced in previous commit. 2017-12-07 10:31:14 +02:00
mpprint.h all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
mpstate.c all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
mpstate.h py/mpstate.h: Remove obsolete comment about nlr_top being coded in asm. 2017-12-11 22:51:52 +11:00
mpthread.h all: Unify header guard usage. 2017-07-18 11:57:39 +10:00
mpz.c py/mpz: Apply a small code-size optimisation. 2017-12-19 15:45:56 +11:00
mpz.h all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
nativeglue.c py/emitnative: Implement floor-division and modulo for viper emitter. 2017-10-11 18:54:34 +11:00
nlr.h Revert "py/nlr: Factor out common NLR code to generic functions." 2017-12-26 19:27:58 +02:00
nlrsetjmp.c Revert "py/nlr: Factor out common NLR code to generic functions." 2017-12-26 19:27:58 +02:00
nlrthumb.c Revert "py/nlr: Factor out common NLR code to generic functions." 2017-12-26 19:27:58 +02:00
nlrx64.c Revert "py/nlr: Factor out common NLR code to generic functions." 2017-12-26 19:27:58 +02:00
nlrx86.c Revert "py/nlr: Factor out common NLR code to generic functions." 2017-12-26 19:27:58 +02:00
nlrxtensa.c Revert "py/nlr: Factor out common NLR code to generic functions." 2017-12-26 19:27:58 +02:00
obj.c all: Remove inclusion of internal py header files. 2017-10-04 12:37:50 +11:00
obj.h py: Extend nan-boxing config to have 47-bit small integers. 2017-12-11 22:39:12 +11:00
objarray.c py/runtime: Add MP_BINARY_OP_CONTAINS as reverse of MP_BINARY_OP_IN. 2017-11-24 14:48:23 +11:00
objarray.h all: Unify header guard usage. 2017-07-18 11:57:39 +10:00
objattrtuple.c all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
objbool.c all: Remove inclusion of internal py header files. 2017-10-04 12:37:50 +11:00
objboundmeth.c py: Convert all uses of alloca() to use new scoped allocation API. 2017-12-11 13:49:09 +11:00
objcell.c all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
objclosure.c all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
objcomplex.c all: Remove inclusion of internal py header files. 2017-10-04 12:37:50 +11:00
objdict.c py/objdict: Reuse dict-view key iterator for standard dict iterator. 2017-11-27 23:40:31 +11:00
objenumerate.c all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
objexcept.c py/objtype: Implement better support for overriding native's __init__. 2017-12-12 16:43:16 +11:00
objexcept.h all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
objfilter.c all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
objfloat.c py/objfloat: Allow float() to parse anything with the buffer protocol. 2017-11-21 15:01:38 +11:00
objfun.c py: Convert all uses of alloca() to use new scoped allocation API. 2017-12-11 13:49:09 +11:00
objfun.h all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
objgenerator.c py/objgenerator: Allow to pend an exception for next execution. 2017-12-15 20:20:36 +02:00
objgenerator.h all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
objgetitemiter.c all: Remove inclusion of internal py header files. 2017-10-04 12:37:50 +11:00
objint_longlong.c py/objint_longlong: Check for zero division/modulo. 2017-12-08 20:40:55 +02:00
objint_mpz.c py/runtime: Add MP_BINARY_OP_CONTAINS as reverse of MP_BINARY_OP_IN. 2017-11-24 14:48:23 +11:00
objint.c all: Remove inclusion of internal py header files. 2017-10-04 12:37:50 +11:00
objint.h py/modbuiltins: Implement abs() by dispatching to MP_UNARY_OP_ABS. 2017-09-18 00:06:43 +03:00
objlist.c all: Use NULL instead of "" when calling mp_raise exception helpers. 2017-10-24 22:39:36 +11:00
objlist.h all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
objmap.c all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
objmodule.c all: Remove inclusion of internal py header files. 2017-10-04 12:37:50 +11:00
objmodule.h all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
objnamedtuple.c py/objnamedtuple: Allow to reuse namedtuple basic functionality. 2017-11-20 09:30:06 +02:00
objnamedtuple.h py/objnamedtuple: Allow to reuse namedtuple basic functionality. 2017-11-20 09:30:06 +02:00
objnone.c all: Remove inclusion of internal py header files. 2017-10-04 12:37:50 +11:00
objobject.c py/objtype: Refactor object's handling of __new__ to not create 2 objs. 2017-12-12 16:53:44 +11:00
objpolyiter.c all: Remove inclusion of internal py header files. 2017-10-04 12:37:50 +11:00
objproperty.c all: Remove inclusion of internal py header files. 2017-10-04 12:37:50 +11:00
objrange.c all: Remove inclusion of internal py header files. 2017-10-04 12:37:50 +11:00
objreversed.c all: Remove inclusion of internal py header files. 2017-10-04 12:37:50 +11:00
objset.c py/objset: Remove unneeded check from set_equal. 2017-12-19 14:01:19 +11:00
objsingleton.c all: Remove inclusion of internal py header files. 2017-10-04 12:37:50 +11:00
objslice.c all: Remove inclusion of internal py header files. 2017-10-04 12:37:50 +11:00
objstr.c py: Annotate func defs with NORETURN when their corresp decls have it. 2017-11-29 15:43:40 +11:00
objstr.h py/objstr: Make mp_obj_new_str_of_type check for existing interned qstr. 2017-11-16 13:53:04 +11:00
objstringio.c all: Remove inclusion of internal py header files. 2017-10-04 12:37:50 +11:00
objstringio.h py/objstringio: If created from immutable object, follow copy on write policy. 2017-06-09 17:33:01 +03:00
objstrunicode.c py/objstr: Remove "make_qstr_if_not_already" arg from mp_obj_new_str. 2017-11-16 13:17:51 +11:00
objtuple.c all: Remove inclusion of internal py header files. 2017-10-04 12:37:50 +11:00
objtuple.h all: Convert mp_uint_t to mp_unary_op_t/mp_binary_op_t where appropriate 2017-08-29 13:16:30 +10:00
objtype.c py/objtype: Refactor object's handling of __new__ to not create 2 objs. 2017-12-12 16:53:44 +11:00
objtype.h py/objtype: Refactor object's handling of __new__ to not create 2 objs. 2017-12-12 16:53:44 +11:00
objzip.c all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
opmethods.c py/runtime: Add MP_BINARY_OP_CONTAINS as reverse of MP_BINARY_OP_IN. 2017-11-24 14:48:23 +11:00
parse.c py: Extend nan-boxing config to have 47-bit small integers. 2017-12-11 22:39:12 +11:00
parse.h all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
parsenum.c py/parsenum: Improve parsing of floating point numbers. 2017-11-27 12:51:52 +11:00
parsenum.h all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
parsenumbase.c all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
parsenumbase.h all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
persistentcode.c py/persistentcode: Bump .mpy version number to version 3. 2017-10-05 10:49:44 +11:00
persistentcode.h py: Factor out persistent-code reader into separate files. 2016-11-16 18:13:50 +11:00
py.mk Revert "py/nlr: Factor out common NLR code to generic functions." 2017-12-26 19:27:58 +02:00
pystack.c py: Introduce a Python stack for scoped allocation. 2017-12-11 13:49:09 +11:00
pystack.h py: Introduce a Python stack for scoped allocation. 2017-12-11 13:49:09 +11:00
qstr.c py/qstr: Rewrite find_qstr to make manifest that it returns a valid ptr. 2017-11-29 17:01:39 +11:00
qstr.h py/compile: Use alloca instead of qstr_build when compiling import name. 2017-11-01 13:16:16 +11:00
qstrdefs.h py/modbuiltins: Use standard arg-parsing helper func for builtin print. 2017-12-05 12:14:57 +11:00
reader.c all: Don't include system errno.h when it's not needed. 2017-07-24 18:43:14 +10:00
reader.h py: Allow lexer to raise exceptions during construction. 2017-03-14 11:52:05 +11:00
repl.c all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
repl.h all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
ringbuf.h all: Unify header guard usage. 2017-07-18 11:57:39 +10:00
runtime0.h py/runtime: Add MP_BINARY_OP_CONTAINS as reverse of MP_BINARY_OP_IN. 2017-11-24 14:48:23 +11:00
runtime_utils.c py: mp_call_function_*_protected(): Pass-thru return value if possible. 2017-12-05 00:38:41 +02:00
runtime.c py/runtime: Remove unnecessary break statements from switch. 2017-12-19 13:13:21 +11:00
runtime.h py: Introduce a Python stack for scoped allocation. 2017-12-11 13:49:09 +11:00
scheduler.c py: Add micropython.schedule() function and associated runtime code. 2017-03-20 15:20:26 +11:00
scope.c all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
scope.h all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
sequence.c all: Remove inclusion of internal py header files. 2017-10-04 12:37:50 +11:00
showbc.c py: Clean up unary and binary enum list to keep groups together. 2017-10-05 10:49:44 +11:00
smallint.c all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
smallint.h py: Extend nan-boxing config to have 47-bit small integers. 2017-12-11 22:39:12 +11:00
stackctrl.c py/runtime: Move mp_exc_recursion_depth to runtime and rename to raise. 2017-12-11 13:49:09 +11:00
stackctrl.h all: Use the name MicroPython consistently in comments 2017-07-31 18:35:40 +10:00
stream.c all: Remove inclusion of internal py header files. 2017-10-04 12:37:50 +11:00
stream.h py/objstringio: Fix regression with handling SEEK_SET. 2017-08-20 22:02:41 +03:00
unicode.c py/objstr: Add check for valid UTF-8 when making a str from bytes. 2017-09-06 16:43:09 +10:00
unicode.h py/objstr: Add check for valid UTF-8 when making a str from bytes. 2017-09-06 16:43:09 +10:00
vm.c py/runtime: Use the Python stack when building *arg and **kwarg state. 2017-12-11 13:49:09 +11:00
vmentrytable.h py: Clean up unary and binary enum list to keep groups together. 2017-10-05 10:49:44 +11:00
vstr.c py/vstr: Raise a RuntimeError if fixed vstr buffer overflows. 2017-09-21 20:29:41 +10:00
warning.c py: Add config option to print warnings/errors to stderr. 2017-09-26 11:59:11 +10:00