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# include <stdio.h>
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# include <string.h>
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# include <assert.h>
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# include "nlr.h"
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# include "misc.h"
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# include "mpconfig.h"
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# include "qstr.h"
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# include "obj.h"
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# include "emitglue.h"
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# include "runtime.h"
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# include "bc0.h"
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# include "bc.h"
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# include "objgenerator.h"
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# define DETECT_VM_STACK_OVERFLOW (0)
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// Value stack grows up (this makes it incompatible with native C stack, but
// makes sure that arguments to functions are in natural order arg1..argN
// (Python semantics mandates left-to-right evaluation order, including for
// function arguments). Stack pointer is pre-incremented and points at the
// top element.
// Exception stack also grows up, top element is also pointed at.
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// Exception stack unwind reasons (WHY_* in CPython-speak)
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// TODO perhaps compress this to RETURN=0, JUMP>0, with number of unwinds
// left to do encoded in the JUMP number
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typedef enum {
UNWIND_RETURN = 1 ,
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UNWIND_JUMP ,
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} mp_unwind_reason_t ;
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# define DECODE_UINT do { \
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unum = 0 ; \
do { \
unum = ( unum < < 7 ) + ( * ip & 0x7f ) ; \
} while ( ( * ip + + & 0x80 ) ! = 0 ) ; \
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} while ( 0 )
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# define DECODE_ULABEL do { unum = (ip[0] | (ip[1] << 8)); ip += 2; } while (0)
# define DECODE_SLABEL do { unum = (ip[0] | (ip[1] << 8)) - 0x8000; ip += 2; } while (0)
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# define DECODE_QSTR do { \
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qst = 0 ; \
do { \
qst = ( qst < < 7 ) + ( * ip & 0x7f ) ; \
} while ( ( * ip + + & 0x80 ) ! = 0 ) ; \
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} while ( 0 )
# define DECODE_PTR do { \
ip = ( byte * ) ( ( ( machine_uint_t ) ip + sizeof ( machine_uint_t ) - 1 ) & ( ~ ( sizeof ( machine_uint_t ) - 1 ) ) ) ; /* align ip */ \
unum = * ( machine_uint_t * ) ip ; \
ip + = sizeof ( machine_uint_t ) ; \
} while ( 0 )
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# define PUSH(val) *++sp = (val)
# define POP() (*sp--)
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# define TOP() (*sp)
# define SET_TOP(val) *sp = (val)
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# define PUSH_EXC_BLOCK() \
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DECODE_ULABEL ; /* except labels are always forward */ \
+ + exc_sp ; \
exc_sp - > opcode = op ; \
exc_sp - > handler = ip + unum ; \
exc_sp - > val_sp = MP_TAGPTR_MAKE ( sp , currently_in_except_block ) ; \
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exc_sp - > prev_exc = MP_OBJ_NULL ; \
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currently_in_except_block = 0 ; /* in a try block now */
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# define POP_EXC_BLOCK() \
currently_in_except_block = MP_TAGPTR_TAG ( exc_sp - > val_sp ) ; /* restore previous state */ \
exc_sp - - ; /* pop back to previous exception handler */
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mp_vm_return_kind_t mp_execute_byte_code ( const byte * code , const mp_obj_t * args , uint n_args , const mp_obj_t * args2 , uint n_args2 , mp_obj_t * ret ) {
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const byte * ip = code ;
// get code info size, and skip line number table
machine_uint_t code_info_size = ip [ 0 ] | ( ip [ 1 ] < < 8 ) | ( ip [ 2 ] < < 16 ) | ( ip [ 3 ] < < 24 ) ;
ip + = code_info_size ;
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// bytecode prelude: state size and exception stack size; 16 bit uints
machine_uint_t n_state = ip [ 0 ] | ( ip [ 1 ] < < 8 ) ;
machine_uint_t n_exc_stack = ip [ 2 ] | ( ip [ 3 ] < < 8 ) ;
ip + = 4 ;
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// allocate state for locals and stack
mp_obj_t temp_state [ 10 ] ;
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mp_obj_t * state = & temp_state [ 0 ] ;
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# if DETECT_VM_STACK_OVERFLOW
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n_state + = 1 ;
# endif
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if ( n_state > 10 ) {
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state = m_new ( mp_obj_t , n_state ) ;
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}
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mp_obj_t * sp = & state [ 0 ] - 1 ;
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// allocate state for exceptions
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mp_exc_stack_t exc_state [ 4 ] ;
mp_exc_stack_t * exc_stack = & exc_state [ 0 ] ;
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if ( n_exc_stack > 4 ) {
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exc_stack = m_new ( mp_exc_stack_t , n_exc_stack ) ;
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}
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mp_exc_stack_t * exc_sp = & exc_stack [ 0 ] - 1 ;
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// init args
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for ( uint i = 0 ; i < n_args ; i + + ) {
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state [ n_state - 1 - i ] = args [ i ] ;
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}
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for ( uint i = 0 ; i < n_args2 ; i + + ) {
state [ n_state - 1 - n_args - i ] = args2 [ i ] ;
}
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// set rest of state to MP_OBJ_NULL
for ( uint i = 0 ; i < n_state - n_args - n_args2 ; i + + ) {
state [ i ] = MP_OBJ_NULL ;
}
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// bytecode prelude: initialise closed over variables
for ( uint n_local = * ip + + ; n_local > 0 ; n_local - - ) {
uint local_num = * ip + + ;
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state [ n_state - 1 - local_num ] = mp_obj_new_cell ( state [ n_state - 1 - local_num ] ) ;
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}
// execute the byte code
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mp_vm_return_kind_t vm_return_kind = mp_execute_byte_code_2 ( code , & ip , & state [ n_state - 1 ] , & sp , exc_stack , & exc_sp , MP_OBJ_NULL ) ;
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# if DETECT_VM_STACK_OVERFLOW
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// We can't check the case when an exception is returned in state[n_state - 1]
// and there are no arguments, because in this case our detection slot may have
// been overwritten by the returned exception (which is allowed).
if ( ! ( vm_return_kind = = MP_VM_RETURN_EXCEPTION & & n_args = = 0 & & n_args2 = = 0 ) ) {
// Just check to see that we have at least 1 null object left in the state.
bool overflow = true ;
for ( uint i = 0 ; i < n_state - n_args - n_args2 ; i + + ) {
if ( state [ i ] = = MP_OBJ_NULL ) {
overflow = false ;
break ;
}
}
if ( overflow ) {
printf ( " VM stack overflow state=%p n_state+1=%u \n " , state , n_state ) ;
assert ( 0 ) ;
}
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}
# endif
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switch ( vm_return_kind ) {
case MP_VM_RETURN_NORMAL :
* ret = * sp ;
return MP_VM_RETURN_NORMAL ;
case MP_VM_RETURN_EXCEPTION :
* ret = state [ n_state - 1 ] ;
return MP_VM_RETURN_EXCEPTION ;
case MP_VM_RETURN_YIELD : // byte-code shouldn't yield
default :
assert ( 0 ) ;
* ret = mp_const_none ;
return MP_VM_RETURN_NORMAL ;
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}
}
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// fastn has items in reverse order (fastn[0] is local[0], fastn[-1] is local[1], etc)
// sp points to bottom of stack which grows up
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// returns:
// MP_VM_RETURN_NORMAL, sp valid, return value in *sp
// MP_VM_RETURN_YIELD, ip, sp valid, yielded value in *sp
// MP_VM_RETURN_EXCEPTION, exception in fastn[0]
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mp_vm_return_kind_t mp_execute_byte_code_2 ( const byte * code_info , const byte * * ip_in_out ,
mp_obj_t * fastn , mp_obj_t * * sp_in_out ,
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mp_exc_stack_t * exc_stack , mp_exc_stack_t * * exc_sp_in_out ,
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volatile mp_obj_t inject_exc ) {
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# if MICROPY_USE_COMPUTED_GOTO
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# include "vmentrytable.h"
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# define DISPATCH() do { \
save_ip = ip ; \
op = * ip + + ; \
goto * entry_table [ op ] ; \
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} while ( 0 )
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# define ENTRY(op) entry_##op
# define ENTRY_DEFAULT entry_default
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# else
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# define DISPATCH() break
# define ENTRY(op) case op
# define ENTRY_DEFAULT default
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# endif
py: Tidy up variables in VM, probably fixes subtle bugs.
Things get tricky when using the nlr code to catch exceptions. Need to
ensure that the variables (stack layout) in the exception handler are
the same as in the bit protected by the exception handler.
Prior to this patch there were a few bugs. 1) The constant
mp_const_MemoryError_obj was being preloaded to a specific location on
the stack at the start of the function. But this location on the stack
was being overwritten in the opcode loop (since it didn't think that
variable would ever be referenced again), and so when an exception
occurred, the variable holding the address of MemoryError was corrupt.
2) The FOR_ITER opcode detection in the exception handler used sp, which
may or may not contain the right value coming out of the main opcode
loop.
With this patch there is a clear separation of variables used in the
opcode loop and in the exception handler (should fix issue (2) above).
Furthermore, nlr_raise is no longer used in the opcode loop. Instead,
it jumps directly into the exception handler. This tells the C compiler
more about the possible code flow, and means that it should have the
same stack layout for the exception handler. This should fix issue (1)
above. Indeed, the generated (ARM) assembler has been checked explicitly,
and with 'goto exception_handler', the problem with &MemoryError is
fixed.
This may now fix problems with rge-sm, and probably many other subtle
bugs yet to show themselves. Incidentally, rge-sm now passes on
pyboard (with a reduced range of integration)!
Main lesson: nlr is tricky. Don't use nlr_push unless you know what you
are doing! Luckily, it's not used in many places. Using nlr_raise/jump
is fine.
2014-04-17 16:50:23 +01:00
// nlr_raise needs to be implemented as a goto, so that the C compiler's flow analyser
// sees that it's possible for us to jump from the dispatch loop to the exception
// handler. Without this, the code may have a different stack layout in the dispatch
// loop and the exception handler, leading to very obscure bugs.
# define RAISE(o) do { nlr_pop(); nlr.ret_val = o; goto exception_handler; } while(0)
2013-10-04 19:53:11 +01:00
py: Tidy up variables in VM, probably fixes subtle bugs.
Things get tricky when using the nlr code to catch exceptions. Need to
ensure that the variables (stack layout) in the exception handler are
the same as in the bit protected by the exception handler.
Prior to this patch there were a few bugs. 1) The constant
mp_const_MemoryError_obj was being preloaded to a specific location on
the stack at the start of the function. But this location on the stack
was being overwritten in the opcode loop (since it didn't think that
variable would ever be referenced again), and so when an exception
occurred, the variable holding the address of MemoryError was corrupt.
2) The FOR_ITER opcode detection in the exception handler used sp, which
may or may not contain the right value coming out of the main opcode
loop.
With this patch there is a clear separation of variables used in the
opcode loop and in the exception handler (should fix issue (2) above).
Furthermore, nlr_raise is no longer used in the opcode loop. Instead,
it jumps directly into the exception handler. This tells the C compiler
more about the possible code flow, and means that it should have the
same stack layout for the exception handler. This should fix issue (1)
above. Indeed, the generated (ARM) assembler has been checked explicitly,
and with 'goto exception_handler', the problem with &MemoryError is
fixed.
This may now fix problems with rge-sm, and probably many other subtle
bugs yet to show themselves. Incidentally, rge-sm now passes on
pyboard (with a reduced range of integration)!
Main lesson: nlr is tricky. Don't use nlr_push unless you know what you
are doing! Luckily, it's not used in many places. Using nlr_raise/jump
is fine.
2014-04-17 16:50:23 +01:00
// variables that are visible to the exception handler (declared volatile)
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volatile bool currently_in_except_block = MP_TAGPTR_TAG ( * exc_sp_in_out ) ; // 0 or 1, to detect nested exceptions
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mp_exc_stack_t * volatile exc_sp = MP_TAGPTR_PTR ( * exc_sp_in_out ) ; // stack grows up, exc_sp points to top of stack
py: Tidy up variables in VM, probably fixes subtle bugs.
Things get tricky when using the nlr code to catch exceptions. Need to
ensure that the variables (stack layout) in the exception handler are
the same as in the bit protected by the exception handler.
Prior to this patch there were a few bugs. 1) The constant
mp_const_MemoryError_obj was being preloaded to a specific location on
the stack at the start of the function. But this location on the stack
was being overwritten in the opcode loop (since it didn't think that
variable would ever be referenced again), and so when an exception
occurred, the variable holding the address of MemoryError was corrupt.
2) The FOR_ITER opcode detection in the exception handler used sp, which
may or may not contain the right value coming out of the main opcode
loop.
With this patch there is a clear separation of variables used in the
opcode loop and in the exception handler (should fix issue (2) above).
Furthermore, nlr_raise is no longer used in the opcode loop. Instead,
it jumps directly into the exception handler. This tells the C compiler
more about the possible code flow, and means that it should have the
same stack layout for the exception handler. This should fix issue (1)
above. Indeed, the generated (ARM) assembler has been checked explicitly,
and with 'goto exception_handler', the problem with &MemoryError is
fixed.
This may now fix problems with rge-sm, and probably many other subtle
bugs yet to show themselves. Incidentally, rge-sm now passes on
pyboard (with a reduced range of integration)!
Main lesson: nlr is tricky. Don't use nlr_push unless you know what you
are doing! Luckily, it's not used in many places. Using nlr_raise/jump
is fine.
2014-04-17 16:50:23 +01:00
const byte * volatile save_ip = * ip_in_out ; // this is so we can access ip in the exception handler without making ip volatile (which means the compiler can't keep it in a register in the main loop)
mp_obj_t * volatile save_sp = * sp_in_out ; // this is so we can access sp in the exception handler when needed
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// outer exception handling loop
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for ( ; ; ) {
py: Tidy up variables in VM, probably fixes subtle bugs.
Things get tricky when using the nlr code to catch exceptions. Need to
ensure that the variables (stack layout) in the exception handler are
the same as in the bit protected by the exception handler.
Prior to this patch there were a few bugs. 1) The constant
mp_const_MemoryError_obj was being preloaded to a specific location on
the stack at the start of the function. But this location on the stack
was being overwritten in the opcode loop (since it didn't think that
variable would ever be referenced again), and so when an exception
occurred, the variable holding the address of MemoryError was corrupt.
2) The FOR_ITER opcode detection in the exception handler used sp, which
may or may not contain the right value coming out of the main opcode
loop.
With this patch there is a clear separation of variables used in the
opcode loop and in the exception handler (should fix issue (2) above).
Furthermore, nlr_raise is no longer used in the opcode loop. Instead,
it jumps directly into the exception handler. This tells the C compiler
more about the possible code flow, and means that it should have the
same stack layout for the exception handler. This should fix issue (1)
above. Indeed, the generated (ARM) assembler has been checked explicitly,
and with 'goto exception_handler', the problem with &MemoryError is
fixed.
This may now fix problems with rge-sm, and probably many other subtle
bugs yet to show themselves. Incidentally, rge-sm now passes on
pyboard (with a reduced range of integration)!
Main lesson: nlr is tricky. Don't use nlr_push unless you know what you
are doing! Luckily, it's not used in many places. Using nlr_raise/jump
is fine.
2014-04-17 16:50:23 +01:00
nlr_buf_t nlr ;
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outer_dispatch_loop :
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if ( nlr_push ( & nlr ) = = 0 ) {
py: Tidy up variables in VM, probably fixes subtle bugs.
Things get tricky when using the nlr code to catch exceptions. Need to
ensure that the variables (stack layout) in the exception handler are
the same as in the bit protected by the exception handler.
Prior to this patch there were a few bugs. 1) The constant
mp_const_MemoryError_obj was being preloaded to a specific location on
the stack at the start of the function. But this location on the stack
was being overwritten in the opcode loop (since it didn't think that
variable would ever be referenced again), and so when an exception
occurred, the variable holding the address of MemoryError was corrupt.
2) The FOR_ITER opcode detection in the exception handler used sp, which
may or may not contain the right value coming out of the main opcode
loop.
With this patch there is a clear separation of variables used in the
opcode loop and in the exception handler (should fix issue (2) above).
Furthermore, nlr_raise is no longer used in the opcode loop. Instead,
it jumps directly into the exception handler. This tells the C compiler
more about the possible code flow, and means that it should have the
same stack layout for the exception handler. This should fix issue (1)
above. Indeed, the generated (ARM) assembler has been checked explicitly,
and with 'goto exception_handler', the problem with &MemoryError is
fixed.
This may now fix problems with rge-sm, and probably many other subtle
bugs yet to show themselves. Incidentally, rge-sm now passes on
pyboard (with a reduced range of integration)!
Main lesson: nlr is tricky. Don't use nlr_push unless you know what you
are doing! Luckily, it's not used in many places. Using nlr_raise/jump
is fine.
2014-04-17 16:50:23 +01:00
// local variables that are not visible to the exception handler
byte op = 0 ;
const byte * ip = * ip_in_out ;
mp_obj_t * sp = * sp_in_out ;
machine_uint_t unum ;
qstr qst ;
mp_obj_t obj1 , obj2 ;
2014-03-22 15:50:12 +00:00
// If we have exception to inject, now that we finish setting up
// execution context, raise it. This works as if RAISE_VARARGS
// bytecode was executed.
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// Injecting exc into yield from generator is a special case,
// handled by MP_BC_YIELD_FROM itself
if ( inject_exc ! = MP_OBJ_NULL & & * ip ! = MP_BC_YIELD_FROM ) {
py: Tidy up variables in VM, probably fixes subtle bugs.
Things get tricky when using the nlr code to catch exceptions. Need to
ensure that the variables (stack layout) in the exception handler are
the same as in the bit protected by the exception handler.
Prior to this patch there were a few bugs. 1) The constant
mp_const_MemoryError_obj was being preloaded to a specific location on
the stack at the start of the function. But this location on the stack
was being overwritten in the opcode loop (since it didn't think that
variable would ever be referenced again), and so when an exception
occurred, the variable holding the address of MemoryError was corrupt.
2) The FOR_ITER opcode detection in the exception handler used sp, which
may or may not contain the right value coming out of the main opcode
loop.
With this patch there is a clear separation of variables used in the
opcode loop and in the exception handler (should fix issue (2) above).
Furthermore, nlr_raise is no longer used in the opcode loop. Instead,
it jumps directly into the exception handler. This tells the C compiler
more about the possible code flow, and means that it should have the
same stack layout for the exception handler. This should fix issue (1)
above. Indeed, the generated (ARM) assembler has been checked explicitly,
and with 'goto exception_handler', the problem with &MemoryError is
fixed.
This may now fix problems with rge-sm, and probably many other subtle
bugs yet to show themselves. Incidentally, rge-sm now passes on
pyboard (with a reduced range of integration)!
Main lesson: nlr is tricky. Don't use nlr_push unless you know what you
are doing! Luckily, it's not used in many places. Using nlr_raise/jump
is fine.
2014-04-17 16:50:23 +01:00
obj1 = inject_exc ;
2014-03-22 15:50:12 +00:00
inject_exc = MP_OBJ_NULL ;
py: Tidy up variables in VM, probably fixes subtle bugs.
Things get tricky when using the nlr code to catch exceptions. Need to
ensure that the variables (stack layout) in the exception handler are
the same as in the bit protected by the exception handler.
Prior to this patch there were a few bugs. 1) The constant
mp_const_MemoryError_obj was being preloaded to a specific location on
the stack at the start of the function. But this location on the stack
was being overwritten in the opcode loop (since it didn't think that
variable would ever be referenced again), and so when an exception
occurred, the variable holding the address of MemoryError was corrupt.
2) The FOR_ITER opcode detection in the exception handler used sp, which
may or may not contain the right value coming out of the main opcode
loop.
With this patch there is a clear separation of variables used in the
opcode loop and in the exception handler (should fix issue (2) above).
Furthermore, nlr_raise is no longer used in the opcode loop. Instead,
it jumps directly into the exception handler. This tells the C compiler
more about the possible code flow, and means that it should have the
same stack layout for the exception handler. This should fix issue (1)
above. Indeed, the generated (ARM) assembler has been checked explicitly,
and with 'goto exception_handler', the problem with &MemoryError is
fixed.
This may now fix problems with rge-sm, and probably many other subtle
bugs yet to show themselves. Incidentally, rge-sm now passes on
pyboard (with a reduced range of integration)!
Main lesson: nlr is tricky. Don't use nlr_push unless you know what you
are doing! Luckily, it's not used in many places. Using nlr_raise/jump
is fine.
2014-04-17 16:50:23 +01:00
obj1 = mp_make_raise_obj ( obj1 ) ;
RAISE ( obj1 ) ;
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}
py: Tidy up variables in VM, probably fixes subtle bugs.
Things get tricky when using the nlr code to catch exceptions. Need to
ensure that the variables (stack layout) in the exception handler are
the same as in the bit protected by the exception handler.
Prior to this patch there were a few bugs. 1) The constant
mp_const_MemoryError_obj was being preloaded to a specific location on
the stack at the start of the function. But this location on the stack
was being overwritten in the opcode loop (since it didn't think that
variable would ever be referenced again), and so when an exception
occurred, the variable holding the address of MemoryError was corrupt.
2) The FOR_ITER opcode detection in the exception handler used sp, which
may or may not contain the right value coming out of the main opcode
loop.
With this patch there is a clear separation of variables used in the
opcode loop and in the exception handler (should fix issue (2) above).
Furthermore, nlr_raise is no longer used in the opcode loop. Instead,
it jumps directly into the exception handler. This tells the C compiler
more about the possible code flow, and means that it should have the
same stack layout for the exception handler. This should fix issue (1)
above. Indeed, the generated (ARM) assembler has been checked explicitly,
and with 'goto exception_handler', the problem with &MemoryError is
fixed.
This may now fix problems with rge-sm, and probably many other subtle
bugs yet to show themselves. Incidentally, rge-sm now passes on
pyboard (with a reduced range of integration)!
Main lesson: nlr is tricky. Don't use nlr_push unless you know what you
are doing! Luckily, it's not used in many places. Using nlr_raise/jump
is fine.
2014-04-17 16:50:23 +01:00
2013-10-15 22:25:17 +01:00
// loop to execute byte code
for ( ; ; ) {
2014-01-31 22:55:05 +00:00
dispatch_loop :
2014-04-17 23:24:13 +01:00
# if MICROPY_USE_COMPUTED_GOTO
2014-04-14 16:22:44 +01:00
DISPATCH ( ) ;
# else
2014-01-18 23:24:36 +00:00
save_ip = ip ;
2014-04-14 16:22:44 +01:00
op = * ip + + ;
2013-10-15 22:25:17 +01:00
2014-04-14 16:22:44 +01:00
switch ( op ) {
# endif
//printf("ip=%p sp=%p op=%u\n", save_ip, sp, op);
2014-04-09 15:26:46 +01:00
2014-04-14 16:22:44 +01:00
ENTRY ( MP_BC_LOAD_CONST_FALSE ) :
PUSH ( mp_const_false ) ;
DISPATCH ( ) ;
2014-04-09 15:26:46 +01:00
2014-04-14 16:22:44 +01:00
ENTRY ( MP_BC_LOAD_CONST_NONE ) :
PUSH ( mp_const_none ) ;
DISPATCH ( ) ;
2014-03-23 19:19:02 +00:00
2014-04-14 16:22:44 +01:00
ENTRY ( MP_BC_LOAD_CONST_TRUE ) :
PUSH ( mp_const_true ) ;
DISPATCH ( ) ;
2014-04-08 21:11:49 +01:00
2014-04-14 16:22:44 +01:00
ENTRY ( MP_BC_LOAD_CONST_ELLIPSIS ) :
PUSH ( ( mp_obj_t ) & mp_const_ellipsis_obj ) ;
DISPATCH ( ) ;
2013-10-15 22:25:17 +01:00
2014-04-14 16:22:44 +01:00
ENTRY ( MP_BC_LOAD_CONST_SMALL_INT ) : {
machine_int_t num = 0 ;
if ( ( ip [ 0 ] & 0x40 ) ! = 0 ) {
// Number is negative
num - - ;
}
do {
num = ( num < < 7 ) | ( * ip & 0x7f ) ;
} while ( ( * ip + + & 0x80 ) ! = 0 ) ;
PUSH ( MP_OBJ_NEW_SMALL_INT ( num ) ) ;
DISPATCH ( ) ;
}
2013-10-15 22:25:17 +01:00
2014-04-14 16:22:44 +01:00
ENTRY ( MP_BC_LOAD_CONST_INT ) :
DECODE_QSTR ;
PUSH ( mp_obj_new_int_from_long_str ( qstr_str ( qst ) ) ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_LOAD_CONST_DEC ) :
DECODE_QSTR ;
PUSH ( mp_load_const_dec ( qst ) ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_LOAD_CONST_ID ) :
DECODE_QSTR ;
PUSH ( mp_load_const_str ( qst ) ) ; // TODO
DISPATCH ( ) ;
ENTRY ( MP_BC_LOAD_CONST_BYTES ) :
DECODE_QSTR ;
PUSH ( mp_load_const_bytes ( qst ) ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_LOAD_CONST_STRING ) :
DECODE_QSTR ;
PUSH ( mp_load_const_str ( qst ) ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_LOAD_NULL ) :
PUSH ( MP_OBJ_NULL ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_LOAD_FAST_0 ) :
obj1 = fastn [ 0 ] ;
goto load_check ;
ENTRY ( MP_BC_LOAD_FAST_1 ) :
obj1 = fastn [ - 1 ] ;
goto load_check ;
ENTRY ( MP_BC_LOAD_FAST_2 ) :
obj1 = fastn [ - 2 ] ;
goto load_check ;
ENTRY ( MP_BC_LOAD_FAST_N ) :
DECODE_UINT ;
obj1 = fastn [ - unum ] ;
load_check :
if ( obj1 = = MP_OBJ_NULL ) {
local_name_error :
py: Tidy up variables in VM, probably fixes subtle bugs.
Things get tricky when using the nlr code to catch exceptions. Need to
ensure that the variables (stack layout) in the exception handler are
the same as in the bit protected by the exception handler.
Prior to this patch there were a few bugs. 1) The constant
mp_const_MemoryError_obj was being preloaded to a specific location on
the stack at the start of the function. But this location on the stack
was being overwritten in the opcode loop (since it didn't think that
variable would ever be referenced again), and so when an exception
occurred, the variable holding the address of MemoryError was corrupt.
2) The FOR_ITER opcode detection in the exception handler used sp, which
may or may not contain the right value coming out of the main opcode
loop.
With this patch there is a clear separation of variables used in the
opcode loop and in the exception handler (should fix issue (2) above).
Furthermore, nlr_raise is no longer used in the opcode loop. Instead,
it jumps directly into the exception handler. This tells the C compiler
more about the possible code flow, and means that it should have the
same stack layout for the exception handler. This should fix issue (1)
above. Indeed, the generated (ARM) assembler has been checked explicitly,
and with 'goto exception_handler', the problem with &MemoryError is
fixed.
This may now fix problems with rge-sm, and probably many other subtle
bugs yet to show themselves. Incidentally, rge-sm now passes on
pyboard (with a reduced range of integration)!
Main lesson: nlr is tricky. Don't use nlr_push unless you know what you
are doing! Luckily, it's not used in many places. Using nlr_raise/jump
is fine.
2014-04-17 16:50:23 +01:00
obj1 = mp_obj_new_exception_msg ( & mp_type_NameError , " local variable referenced before assignment " ) ;
RAISE ( obj1 ) ;
2014-04-14 16:22:44 +01:00
}
PUSH ( obj1 ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_LOAD_DEREF ) :
DECODE_UINT ;
obj1 = mp_obj_cell_get ( fastn [ - unum ] ) ;
goto load_check ;
ENTRY ( MP_BC_LOAD_NAME ) :
DECODE_QSTR ;
PUSH ( mp_load_name ( qst ) ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_LOAD_GLOBAL ) :
DECODE_QSTR ;
PUSH ( mp_load_global ( qst ) ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_LOAD_ATTR ) :
DECODE_QSTR ;
SET_TOP ( mp_load_attr ( TOP ( ) , qst ) ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_LOAD_METHOD ) :
DECODE_QSTR ;
mp_load_method ( * sp , qst , sp ) ;
sp + = 1 ;
DISPATCH ( ) ;
ENTRY ( MP_BC_LOAD_BUILD_CLASS ) :
PUSH ( mp_load_build_class ( ) ) ;
DISPATCH ( ) ;
2014-04-17 22:10:53 +01:00
ENTRY ( MP_BC_LOAD_SUBSCR ) :
obj1 = POP ( ) ;
SET_TOP ( mp_obj_subscr ( TOP ( ) , obj1 , MP_OBJ_SENTINEL ) ) ;
DISPATCH ( ) ;
2014-04-14 16:22:44 +01:00
ENTRY ( MP_BC_STORE_FAST_0 ) :
fastn [ 0 ] = POP ( ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_STORE_FAST_1 ) :
fastn [ - 1 ] = POP ( ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_STORE_FAST_2 ) :
fastn [ - 2 ] = POP ( ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_STORE_FAST_N ) :
DECODE_UINT ;
fastn [ - unum ] = POP ( ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_STORE_DEREF ) :
DECODE_UINT ;
mp_obj_cell_set ( fastn [ - unum ] , POP ( ) ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_STORE_NAME ) :
DECODE_QSTR ;
mp_store_name ( qst , POP ( ) ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_STORE_GLOBAL ) :
DECODE_QSTR ;
mp_store_global ( qst , POP ( ) ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_STORE_ATTR ) :
DECODE_QSTR ;
mp_store_attr ( sp [ 0 ] , qst , sp [ - 1 ] ) ;
sp - = 2 ;
DISPATCH ( ) ;
ENTRY ( MP_BC_STORE_SUBSCR ) :
2014-04-17 22:10:53 +01:00
mp_obj_subscr ( sp [ - 1 ] , sp [ 0 ] , sp [ - 2 ] ) ;
2014-04-14 16:22:44 +01:00
sp - = 3 ;
DISPATCH ( ) ;
ENTRY ( MP_BC_DELETE_FAST ) :
DECODE_UINT ;
if ( fastn [ - unum ] = = MP_OBJ_NULL ) {
goto local_name_error ;
}
fastn [ - unum ] = MP_OBJ_NULL ;
DISPATCH ( ) ;
2013-10-15 22:25:17 +01:00
2014-04-14 16:22:44 +01:00
ENTRY ( MP_BC_DELETE_DEREF ) :
DECODE_UINT ;
if ( mp_obj_cell_get ( fastn [ - unum ] ) = = MP_OBJ_NULL ) {
goto local_name_error ;
}
mp_obj_cell_set ( fastn [ - unum ] , MP_OBJ_NULL ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_DELETE_NAME ) :
DECODE_QSTR ;
mp_delete_name ( qst ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_DELETE_GLOBAL ) :
DECODE_QSTR ;
mp_delete_global ( qst ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_DUP_TOP ) :
obj1 = TOP ( ) ;
PUSH ( obj1 ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_DUP_TOP_TWO ) :
sp + = 2 ;
sp [ 0 ] = sp [ - 2 ] ;
sp [ - 1 ] = sp [ - 3 ] ;
DISPATCH ( ) ;
ENTRY ( MP_BC_POP_TOP ) :
sp - = 1 ;
DISPATCH ( ) ;
ENTRY ( MP_BC_ROT_TWO ) :
obj1 = sp [ 0 ] ;
sp [ 0 ] = sp [ - 1 ] ;
sp [ - 1 ] = obj1 ;
DISPATCH ( ) ;
ENTRY ( MP_BC_ROT_THREE ) :
obj1 = sp [ 0 ] ;
sp [ 0 ] = sp [ - 1 ] ;
sp [ - 1 ] = sp [ - 2 ] ;
sp [ - 2 ] = obj1 ;
DISPATCH ( ) ;
ENTRY ( MP_BC_JUMP ) :
DECODE_SLABEL ;
ip + = unum ;
DISPATCH ( ) ;
ENTRY ( MP_BC_POP_JUMP_IF_TRUE ) :
DECODE_SLABEL ;
if ( mp_obj_is_true ( POP ( ) ) ) {
ip + = unum ;
}
DISPATCH ( ) ;
2013-11-09 20:12:32 +00:00
2014-04-14 16:22:44 +01:00
ENTRY ( MP_BC_POP_JUMP_IF_FALSE ) :
DECODE_SLABEL ;
if ( ! mp_obj_is_true ( POP ( ) ) ) {
ip + = unum ;
}
DISPATCH ( ) ;
2013-11-09 20:12:32 +00:00
2014-04-14 16:22:44 +01:00
ENTRY ( MP_BC_JUMP_IF_TRUE_OR_POP ) :
DECODE_SLABEL ;
if ( mp_obj_is_true ( TOP ( ) ) ) {
ip + = unum ;
} else {
sp - - ;
}
DISPATCH ( ) ;
2013-10-15 22:25:17 +01:00
2014-04-14 16:22:44 +01:00
ENTRY ( MP_BC_JUMP_IF_FALSE_OR_POP ) :
DECODE_SLABEL ;
if ( mp_obj_is_true ( TOP ( ) ) ) {
sp - - ;
} else {
ip + = unum ;
}
DISPATCH ( ) ;
/* we are trying to get away without using this opcode
ENTRY ( MP_BC_SETUP_LOOP ) :
DECODE_UINT ;
// push_block(MP_BC_SETUP_LOOP, ip + unum, sp)
DISPATCH ( ) ;
*/
ENTRY ( MP_BC_SETUP_WITH ) :
obj1 = TOP ( ) ;
SET_TOP ( mp_load_attr ( obj1 , MP_QSTR___exit__ ) ) ;
mp_load_method ( obj1 , MP_QSTR___enter__ , sp + 1 ) ;
obj2 = mp_call_method_n_kw ( 0 , 0 , sp + 1 ) ;
PUSH_EXC_BLOCK ( ) ;
PUSH ( obj2 ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_WITH_CLEANUP ) : {
// Arriving here, there's "exception control block" on top of stack,
// and __exit__ bound method underneath it. Bytecode calls __exit__,
// and "deletes" it off stack, shifting "exception control block"
// to its place.
static const mp_obj_t no_exc [ ] = { mp_const_none , mp_const_none , mp_const_none } ;
if ( TOP ( ) = = mp_const_none ) {
sp - - ;
2014-03-29 02:10:11 +00:00
obj1 = TOP ( ) ;
2014-04-14 16:22:44 +01:00
SET_TOP ( mp_const_none ) ;
obj2 = mp_call_function_n_kw ( obj1 , 3 , 0 , no_exc ) ;
} else if ( MP_OBJ_IS_SMALL_INT ( TOP ( ) ) ) {
mp_obj_t cause = POP ( ) ;
switch ( MP_OBJ_SMALL_INT_VALUE ( cause ) ) {
case UNWIND_RETURN : {
mp_obj_t retval = POP ( ) ;
obj2 = mp_call_function_n_kw ( TOP ( ) , 3 , 0 , no_exc ) ;
SET_TOP ( retval ) ;
PUSH ( cause ) ;
break ;
2014-03-29 02:10:11 +00:00
}
2014-04-14 16:22:44 +01:00
case UNWIND_JUMP : {
obj2 = mp_call_function_n_kw ( sp [ - 2 ] , 3 , 0 , no_exc ) ;
// Pop __exit__ boundmethod at sp[-2]
sp [ - 2 ] = sp [ - 1 ] ;
sp [ - 1 ] = sp [ 0 ] ;
SET_TOP ( cause ) ;
break ;
2014-03-29 02:10:11 +00:00
}
2014-04-14 16:22:44 +01:00
default :
assert ( 0 ) ;
2014-03-29 02:10:11 +00:00
}
2014-04-14 16:22:44 +01:00
} else if ( mp_obj_is_exception_type ( TOP ( ) ) ) {
mp_obj_t args [ 3 ] = { sp [ 0 ] , sp [ - 1 ] , sp [ - 2 ] } ;
obj2 = mp_call_function_n_kw ( sp [ - 3 ] , 3 , 0 , args ) ;
// Pop __exit__ boundmethod at sp[-3]
// TODO: Once semantics is proven, optimize for case when obj2 == True
sp [ - 3 ] = sp [ - 2 ] ;
sp [ - 2 ] = sp [ - 1 ] ;
sp [ - 1 ] = sp [ 0 ] ;
sp - - ;
if ( mp_obj_is_true ( obj2 ) ) {
// This is what CPython does
//PUSH(MP_OBJ_NEW_SMALL_INT(UNWIND_SILENCED));
// But what we need to do is - pop exception from value stack...
sp - = 3 ;
// ... pop "with" exception handler, and signal END_FINALLY
// to just execute finally handler normally (by pushing None
// on value stack)
2014-02-01 20:08:18 +00:00
assert ( exc_sp > = exc_stack ) ;
2014-04-14 16:22:44 +01:00
assert ( exc_sp - > opcode = = MP_BC_SETUP_WITH ) ;
POP_EXC_BLOCK ( ) ;
PUSH ( mp_const_none ) ;
2014-01-30 11:49:18 +00:00
}
2014-04-14 16:22:44 +01:00
} else {
assert ( 0 ) ;
}
DISPATCH ( ) ;
}
2013-10-15 22:25:17 +01:00
2014-04-14 16:22:44 +01:00
ENTRY ( MP_BC_UNWIND_JUMP ) :
DECODE_SLABEL ;
PUSH ( ( void * ) ( ip + unum ) ) ; // push destination ip for jump
PUSH ( ( void * ) ( machine_uint_t ) ( * ip ) ) ; // push number of exception handlers to unwind
unwind_jump :
unum = ( machine_uint_t ) POP ( ) ; // get number of exception handlers to unwind
while ( unum > 0 ) {
unum - = 1 ;
2014-03-22 11:49:31 +00:00
assert ( exc_sp > = exc_stack ) ;
2014-04-14 16:22:44 +01:00
if ( exc_sp - > opcode = = MP_BC_SETUP_FINALLY | | exc_sp - > opcode = = MP_BC_SETUP_WITH ) {
// We're going to run "finally" code as a coroutine
// (not calling it recursively). Set up a sentinel
// on a stack so it can return back to us when it is
// done (when END_FINALLY reached).
PUSH ( ( void * ) unum ) ; // push number of exception handlers left to unwind
PUSH ( MP_OBJ_NEW_SMALL_INT ( UNWIND_JUMP ) ) ; // push sentinel
ip = exc_sp - > handler ; // get exception handler byte code address
exc_sp - - ; // pop exception handler
goto dispatch_loop ; // run the exception handler
2014-02-01 23:04:09 +00:00
}
2014-04-14 16:22:44 +01:00
exc_sp - - ;
}
ip = ( const byte * ) POP ( ) ; // pop destination ip for jump
DISPATCH ( ) ;
// matched against: POP_BLOCK or POP_EXCEPT (anything else?)
ENTRY ( MP_BC_SETUP_EXCEPT ) :
ENTRY ( MP_BC_SETUP_FINALLY ) :
PUSH_EXC_BLOCK ( ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_END_FINALLY ) :
// not fully implemented
// if TOS is an exception, reraises the exception (3 values on TOS)
// if TOS is None, just pops it and continues
// if TOS is an integer, does something else
// else error
if ( mp_obj_is_exception_type ( TOP ( ) ) ) {
py: Tidy up variables in VM, probably fixes subtle bugs.
Things get tricky when using the nlr code to catch exceptions. Need to
ensure that the variables (stack layout) in the exception handler are
the same as in the bit protected by the exception handler.
Prior to this patch there were a few bugs. 1) The constant
mp_const_MemoryError_obj was being preloaded to a specific location on
the stack at the start of the function. But this location on the stack
was being overwritten in the opcode loop (since it didn't think that
variable would ever be referenced again), and so when an exception
occurred, the variable holding the address of MemoryError was corrupt.
2) The FOR_ITER opcode detection in the exception handler used sp, which
may or may not contain the right value coming out of the main opcode
loop.
With this patch there is a clear separation of variables used in the
opcode loop and in the exception handler (should fix issue (2) above).
Furthermore, nlr_raise is no longer used in the opcode loop. Instead,
it jumps directly into the exception handler. This tells the C compiler
more about the possible code flow, and means that it should have the
same stack layout for the exception handler. This should fix issue (1)
above. Indeed, the generated (ARM) assembler has been checked explicitly,
and with 'goto exception_handler', the problem with &MemoryError is
fixed.
This may now fix problems with rge-sm, and probably many other subtle
bugs yet to show themselves. Incidentally, rge-sm now passes on
pyboard (with a reduced range of integration)!
Main lesson: nlr is tricky. Don't use nlr_push unless you know what you
are doing! Luckily, it's not used in many places. Using nlr_raise/jump
is fine.
2014-04-17 16:50:23 +01:00
RAISE ( sp [ - 1 ] ) ;
2014-04-14 16:22:44 +01:00
}
if ( TOP ( ) = = mp_const_none ) {
2014-01-18 14:10:48 +00:00
sp - - ;
2014-04-14 16:22:44 +01:00
} else if ( MP_OBJ_IS_SMALL_INT ( TOP ( ) ) ) {
// We finished "finally" coroutine and now dispatch back
// to our caller, based on TOS value
mp_unwind_reason_t reason = MP_OBJ_SMALL_INT_VALUE ( POP ( ) ) ;
switch ( reason ) {
case UNWIND_RETURN :
goto unwind_return ;
case UNWIND_JUMP :
goto unwind_jump ;
}
assert ( 0 ) ;
} else {
assert ( 0 ) ;
}
DISPATCH ( ) ;
ENTRY ( MP_BC_GET_ITER ) :
SET_TOP ( mp_getiter ( TOP ( ) ) ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_FOR_ITER ) :
DECODE_ULABEL ; // the jump offset if iteration finishes; for labels are always forward
py: Tidy up variables in VM, probably fixes subtle bugs.
Things get tricky when using the nlr code to catch exceptions. Need to
ensure that the variables (stack layout) in the exception handler are
the same as in the bit protected by the exception handler.
Prior to this patch there were a few bugs. 1) The constant
mp_const_MemoryError_obj was being preloaded to a specific location on
the stack at the start of the function. But this location on the stack
was being overwritten in the opcode loop (since it didn't think that
variable would ever be referenced again), and so when an exception
occurred, the variable holding the address of MemoryError was corrupt.
2) The FOR_ITER opcode detection in the exception handler used sp, which
may or may not contain the right value coming out of the main opcode
loop.
With this patch there is a clear separation of variables used in the
opcode loop and in the exception handler (should fix issue (2) above).
Furthermore, nlr_raise is no longer used in the opcode loop. Instead,
it jumps directly into the exception handler. This tells the C compiler
more about the possible code flow, and means that it should have the
same stack layout for the exception handler. This should fix issue (1)
above. Indeed, the generated (ARM) assembler has been checked explicitly,
and with 'goto exception_handler', the problem with &MemoryError is
fixed.
This may now fix problems with rge-sm, and probably many other subtle
bugs yet to show themselves. Incidentally, rge-sm now passes on
pyboard (with a reduced range of integration)!
Main lesson: nlr is tricky. Don't use nlr_push unless you know what you
are doing! Luckily, it's not used in many places. Using nlr_raise/jump
is fine.
2014-04-17 16:50:23 +01:00
save_sp = sp ;
2014-04-14 16:22:44 +01:00
obj1 = mp_iternext_allow_raise ( TOP ( ) ) ;
2014-04-17 23:19:36 +01:00
if ( obj1 = = MP_OBJ_STOP_ITERATION ) {
2014-04-14 16:22:44 +01:00
- - sp ; // pop the exhausted iterator
ip + = unum ; // jump to after for-block
} else {
PUSH ( obj1 ) ; // push the next iteration value
}
DISPATCH ( ) ;
// matched against: SETUP_EXCEPT, SETUP_FINALLY, SETUP_WITH
ENTRY ( MP_BC_POP_BLOCK ) :
// we are exiting an exception handler, so pop the last one of the exception-stack
assert ( exc_sp > = exc_stack ) ;
POP_EXC_BLOCK ( ) ;
DISPATCH ( ) ;
// matched against: SETUP_EXCEPT
ENTRY ( MP_BC_POP_EXCEPT ) :
// TODO need to work out how blocks work etc
// pops block, checks it's an exception block, and restores the stack, saving the 3 exception values to local threadstate
assert ( exc_sp > = exc_stack ) ;
assert ( currently_in_except_block ) ;
//sp = (mp_obj_t*)(*exc_sp--);
//exc_sp--; // discard ip
POP_EXC_BLOCK ( ) ;
//sp -= 3; // pop 3 exception values
DISPATCH ( ) ;
ENTRY ( MP_BC_NOT ) :
if ( TOP ( ) = = mp_const_true ) {
SET_TOP ( mp_const_false ) ;
} else {
SET_TOP ( mp_const_true ) ;
}
DISPATCH ( ) ;
ENTRY ( MP_BC_UNARY_OP ) :
unum = * ip + + ;
SET_TOP ( mp_unary_op ( unum , TOP ( ) ) ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_BINARY_OP ) :
unum = * ip + + ;
obj2 = POP ( ) ;
obj1 = TOP ( ) ;
SET_TOP ( mp_binary_op ( unum , obj1 , obj2 ) ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_BUILD_TUPLE ) :
DECODE_UINT ;
sp - = unum - 1 ;
SET_TOP ( mp_obj_new_tuple ( unum , sp ) ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_BUILD_LIST ) :
DECODE_UINT ;
sp - = unum - 1 ;
SET_TOP ( mp_obj_new_list ( unum , sp ) ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_LIST_APPEND ) :
DECODE_UINT ;
// I think it's guaranteed by the compiler that sp[unum] is a list
mp_obj_list_append ( sp [ - unum ] , sp [ 0 ] ) ;
sp - - ;
DISPATCH ( ) ;
ENTRY ( MP_BC_BUILD_MAP ) :
DECODE_UINT ;
PUSH ( mp_obj_new_dict ( unum ) ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_STORE_MAP ) :
sp - = 2 ;
mp_obj_dict_store ( sp [ 0 ] , sp [ 2 ] , sp [ 1 ] ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_MAP_ADD ) :
DECODE_UINT ;
// I think it's guaranteed by the compiler that sp[-unum - 1] is a map
mp_obj_dict_store ( sp [ - unum - 1 ] , sp [ 0 ] , sp [ - 1 ] ) ;
sp - = 2 ;
DISPATCH ( ) ;
ENTRY ( MP_BC_BUILD_SET ) :
DECODE_UINT ;
sp - = unum - 1 ;
SET_TOP ( mp_obj_new_set ( unum , sp ) ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_SET_ADD ) :
DECODE_UINT ;
// I think it's guaranteed by the compiler that sp[-unum] is a set
mp_obj_set_store ( sp [ - unum ] , sp [ 0 ] ) ;
sp - - ;
DISPATCH ( ) ;
2013-10-16 20:57:49 +01:00
2014-01-03 23:34:23 +00:00
# if MICROPY_ENABLE_SLICE
2014-04-14 16:22:44 +01:00
ENTRY ( MP_BC_BUILD_SLICE ) :
DECODE_UINT ;
if ( unum = = 2 ) {
obj2 = POP ( ) ;
obj1 = TOP ( ) ;
SET_TOP ( mp_obj_new_slice ( obj1 , obj2 , NULL ) ) ;
} else {
obj1 = mp_obj_new_exception_msg ( & mp_type_NotImplementedError , " 3-argument slice is not supported " ) ;
nlr_pop ( ) ;
fastn [ 0 ] = obj1 ;
return MP_VM_RETURN_EXCEPTION ;
}
DISPATCH ( ) ;
2014-01-03 23:34:23 +00:00
# endif
2014-01-03 00:48:56 +00:00
2014-04-14 16:22:44 +01:00
ENTRY ( MP_BC_UNPACK_SEQUENCE ) :
DECODE_UINT ;
mp_unpack_sequence ( sp [ 0 ] , unum , sp ) ;
sp + = unum - 1 ;
DISPATCH ( ) ;
ENTRY ( MP_BC_UNPACK_EX ) :
DECODE_UINT ;
mp_unpack_ex ( sp [ 0 ] , unum , sp ) ;
sp + = ( unum & 0xff ) + ( ( unum > > 8 ) & 0xff ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_MAKE_FUNCTION ) :
DECODE_PTR ;
PUSH ( mp_make_function_from_raw_code ( ( mp_raw_code_t * ) unum , MP_OBJ_NULL , MP_OBJ_NULL ) ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_MAKE_FUNCTION_DEFARGS ) :
DECODE_PTR ;
// Stack layout: def_tuple def_dict <- TOS
obj1 = POP ( ) ;
SET_TOP ( mp_make_function_from_raw_code ( ( mp_raw_code_t * ) unum , TOP ( ) , obj1 ) ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_MAKE_CLOSURE ) :
DECODE_PTR ;
// Stack layout: closure_tuple <- TOS
SET_TOP ( mp_make_closure_from_raw_code ( ( mp_raw_code_t * ) unum , TOP ( ) , MP_OBJ_NULL , MP_OBJ_NULL ) ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_MAKE_CLOSURE_DEFARGS ) :
DECODE_PTR ;
// Stack layout: def_tuple def_dict closure_tuple <- TOS
obj1 = POP ( ) ;
obj2 = POP ( ) ;
SET_TOP ( mp_make_closure_from_raw_code ( ( mp_raw_code_t * ) unum , obj1 , TOP ( ) , obj2 ) ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_CALL_FUNCTION ) :
DECODE_UINT ;
// unum & 0xff == n_positional
// (unum >> 8) & 0xff == n_keyword
sp - = ( unum & 0xff ) + ( ( unum > > 7 ) & 0x1fe ) ;
SET_TOP ( mp_call_function_n_kw ( * sp , unum & 0xff , ( unum > > 8 ) & 0xff , sp + 1 ) ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_CALL_FUNCTION_VAR_KW ) :
DECODE_UINT ;
// unum & 0xff == n_positional
// (unum >> 8) & 0xff == n_keyword
// We have folowing stack layout here:
// fun arg0 arg1 ... kw0 val0 kw1 val1 ... seq dict <- TOS
sp - = ( unum & 0xff ) + ( ( unum > > 7 ) & 0x1fe ) + 2 ;
SET_TOP ( mp_call_method_n_kw_var ( false , unum , sp ) ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_CALL_METHOD ) :
DECODE_UINT ;
// unum & 0xff == n_positional
// (unum >> 8) & 0xff == n_keyword
sp - = ( unum & 0xff ) + ( ( unum > > 7 ) & 0x1fe ) + 1 ;
SET_TOP ( mp_call_method_n_kw ( unum & 0xff , ( unum > > 8 ) & 0xff , sp ) ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_CALL_METHOD_VAR_KW ) :
DECODE_UINT ;
// unum & 0xff == n_positional
// (unum >> 8) & 0xff == n_keyword
// We have folowing stack layout here:
// fun self arg0 arg1 ... kw0 val0 kw1 val1 ... seq dict <- TOS
sp - = ( unum & 0xff ) + ( ( unum > > 7 ) & 0x1fe ) + 3 ;
SET_TOP ( mp_call_method_n_kw_var ( true , unum , sp ) ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_RETURN_VALUE ) :
2014-01-31 22:55:05 +00:00
unwind_return :
2014-04-14 16:22:44 +01:00
while ( exc_sp > = exc_stack ) {
if ( exc_sp - > opcode = = MP_BC_SETUP_FINALLY | | exc_sp - > opcode = = MP_BC_SETUP_WITH ) {
// We're going to run "finally" code as a coroutine
// (not calling it recursively). Set up a sentinel
// on a stack so it can return back to us when it is
// done (when END_FINALLY reached).
PUSH ( MP_OBJ_NEW_SMALL_INT ( UNWIND_RETURN ) ) ;
ip = exc_sp - > handler ;
// We don't need to do anything with sp, finally is just
// syntactic sugar for sequential execution??
// sp =
2014-01-31 22:55:05 +00:00
exc_sp - - ;
2014-04-14 16:22:44 +01:00
goto dispatch_loop ;
2014-01-31 22:55:05 +00:00
}
2014-04-14 16:22:44 +01:00
exc_sp - - ;
}
nlr_pop ( ) ;
* sp_in_out = sp ;
assert ( exc_sp = = exc_stack - 1 ) ;
return MP_VM_RETURN_NORMAL ;
ENTRY ( MP_BC_RAISE_VARARGS ) :
unum = * ip + + ;
assert ( unum < = 1 ) ;
if ( unum = = 0 ) {
// search for the inner-most previous exception, to reraise it
obj1 = MP_OBJ_NULL ;
for ( mp_exc_stack_t * e = exc_sp ; e > = exc_stack ; e - - ) {
if ( e - > prev_exc ! = MP_OBJ_NULL ) {
obj1 = e - > prev_exc ;
break ;
2014-03-29 17:44:15 +00:00
}
2014-03-26 12:42:17 +00:00
}
2014-04-14 16:22:44 +01:00
if ( obj1 = = MP_OBJ_NULL ) {
py: Tidy up variables in VM, probably fixes subtle bugs.
Things get tricky when using the nlr code to catch exceptions. Need to
ensure that the variables (stack layout) in the exception handler are
the same as in the bit protected by the exception handler.
Prior to this patch there were a few bugs. 1) The constant
mp_const_MemoryError_obj was being preloaded to a specific location on
the stack at the start of the function. But this location on the stack
was being overwritten in the opcode loop (since it didn't think that
variable would ever be referenced again), and so when an exception
occurred, the variable holding the address of MemoryError was corrupt.
2) The FOR_ITER opcode detection in the exception handler used sp, which
may or may not contain the right value coming out of the main opcode
loop.
With this patch there is a clear separation of variables used in the
opcode loop and in the exception handler (should fix issue (2) above).
Furthermore, nlr_raise is no longer used in the opcode loop. Instead,
it jumps directly into the exception handler. This tells the C compiler
more about the possible code flow, and means that it should have the
same stack layout for the exception handler. This should fix issue (1)
above. Indeed, the generated (ARM) assembler has been checked explicitly,
and with 'goto exception_handler', the problem with &MemoryError is
fixed.
This may now fix problems with rge-sm, and probably many other subtle
bugs yet to show themselves. Incidentally, rge-sm now passes on
pyboard (with a reduced range of integration)!
Main lesson: nlr is tricky. Don't use nlr_push unless you know what you
are doing! Luckily, it's not used in many places. Using nlr_raise/jump
is fine.
2014-04-17 16:50:23 +01:00
obj1 = mp_obj_new_exception_msg ( & mp_type_RuntimeError , " No active exception to reraise " ) ;
RAISE ( obj1 ) ;
2014-04-14 16:22:44 +01:00
}
} else {
obj1 = POP ( ) ;
}
py: Tidy up variables in VM, probably fixes subtle bugs.
Things get tricky when using the nlr code to catch exceptions. Need to
ensure that the variables (stack layout) in the exception handler are
the same as in the bit protected by the exception handler.
Prior to this patch there were a few bugs. 1) The constant
mp_const_MemoryError_obj was being preloaded to a specific location on
the stack at the start of the function. But this location on the stack
was being overwritten in the opcode loop (since it didn't think that
variable would ever be referenced again), and so when an exception
occurred, the variable holding the address of MemoryError was corrupt.
2) The FOR_ITER opcode detection in the exception handler used sp, which
may or may not contain the right value coming out of the main opcode
loop.
With this patch there is a clear separation of variables used in the
opcode loop and in the exception handler (should fix issue (2) above).
Furthermore, nlr_raise is no longer used in the opcode loop. Instead,
it jumps directly into the exception handler. This tells the C compiler
more about the possible code flow, and means that it should have the
same stack layout for the exception handler. This should fix issue (1)
above. Indeed, the generated (ARM) assembler has been checked explicitly,
and with 'goto exception_handler', the problem with &MemoryError is
fixed.
This may now fix problems with rge-sm, and probably many other subtle
bugs yet to show themselves. Incidentally, rge-sm now passes on
pyboard (with a reduced range of integration)!
Main lesson: nlr is tricky. Don't use nlr_push unless you know what you
are doing! Luckily, it's not used in many places. Using nlr_raise/jump
is fine.
2014-04-17 16:50:23 +01:00
obj1 = mp_make_raise_obj ( obj1 ) ;
RAISE ( obj1 ) ;
2014-01-10 14:09:55 +00:00
2014-04-14 16:22:44 +01:00
ENTRY ( MP_BC_YIELD_VALUE ) :
2014-03-26 15:36:12 +00:00
yield :
2014-04-14 16:22:44 +01:00
nlr_pop ( ) ;
* ip_in_out = ip ;
* sp_in_out = sp ;
* exc_sp_in_out = MP_TAGPTR_MAKE ( exc_sp , currently_in_except_block ) ;
return MP_VM_RETURN_YIELD ;
2013-10-15 22:25:17 +01:00
2014-04-14 16:22:44 +01:00
ENTRY ( MP_BC_YIELD_FROM ) : {
2014-03-26 15:36:12 +00:00
//#define EXC_MATCH(exc, type) MP_OBJ_IS_TYPE(exc, type)
# define EXC_MATCH(exc, type) mp_obj_exception_match(exc, type)
py: Tidy up variables in VM, probably fixes subtle bugs.
Things get tricky when using the nlr code to catch exceptions. Need to
ensure that the variables (stack layout) in the exception handler are
the same as in the bit protected by the exception handler.
Prior to this patch there were a few bugs. 1) The constant
mp_const_MemoryError_obj was being preloaded to a specific location on
the stack at the start of the function. But this location on the stack
was being overwritten in the opcode loop (since it didn't think that
variable would ever be referenced again), and so when an exception
occurred, the variable holding the address of MemoryError was corrupt.
2) The FOR_ITER opcode detection in the exception handler used sp, which
may or may not contain the right value coming out of the main opcode
loop.
With this patch there is a clear separation of variables used in the
opcode loop and in the exception handler (should fix issue (2) above).
Furthermore, nlr_raise is no longer used in the opcode loop. Instead,
it jumps directly into the exception handler. This tells the C compiler
more about the possible code flow, and means that it should have the
same stack layout for the exception handler. This should fix issue (1)
above. Indeed, the generated (ARM) assembler has been checked explicitly,
and with 'goto exception_handler', the problem with &MemoryError is
fixed.
This may now fix problems with rge-sm, and probably many other subtle
bugs yet to show themselves. Incidentally, rge-sm now passes on
pyboard (with a reduced range of integration)!
Main lesson: nlr is tricky. Don't use nlr_push unless you know what you
are doing! Luckily, it's not used in many places. Using nlr_raise/jump
is fine.
2014-04-17 16:50:23 +01:00
# define GENERATOR_EXIT_IF_NEEDED(t) if (t != MP_OBJ_NULL && EXC_MATCH(t, &mp_type_GeneratorExit)) { RAISE(t); }
2014-04-14 16:22:44 +01:00
mp_vm_return_kind_t ret_kind ;
obj1 = POP ( ) ;
mp_obj_t t_exc = MP_OBJ_NULL ;
if ( inject_exc ! = MP_OBJ_NULL ) {
t_exc = inject_exc ;
inject_exc = MP_OBJ_NULL ;
ret_kind = mp_resume ( TOP ( ) , MP_OBJ_NULL , t_exc , & obj2 ) ;
} else {
ret_kind = mp_resume ( TOP ( ) , obj1 , MP_OBJ_NULL , & obj2 ) ;
}
2014-03-26 15:36:12 +00:00
2014-04-14 16:22:44 +01:00
if ( ret_kind = = MP_VM_RETURN_YIELD ) {
ip - - ;
PUSH ( obj2 ) ;
goto yield ;
}
if ( ret_kind = = MP_VM_RETURN_NORMAL ) {
// Pop exhausted gen
sp - - ;
if ( obj2 = = MP_OBJ_NULL ) {
// Optimize StopIteration
// TODO: get StopIteration's value
PUSH ( mp_const_none ) ;
} else {
2014-03-26 15:36:12 +00:00
PUSH ( obj2 ) ;
}
2014-04-14 16:22:44 +01:00
// If we injected GeneratorExit downstream, then even
// if it was swallowed, we re-raise GeneratorExit
GENERATOR_EXIT_IF_NEEDED ( t_exc ) ;
DISPATCH ( ) ;
}
if ( ret_kind = = MP_VM_RETURN_EXCEPTION ) {
// Pop exhausted gen
sp - - ;
if ( EXC_MATCH ( obj2 , & mp_type_StopIteration ) ) {
PUSH ( mp_obj_exception_get_value ( obj2 ) ) ;
2014-03-26 17:24:03 +00:00
// If we injected GeneratorExit downstream, then even
// if it was swallowed, we re-raise GeneratorExit
GENERATOR_EXIT_IF_NEEDED ( t_exc ) ;
2014-04-14 16:22:44 +01:00
DISPATCH ( ) ;
} else {
py: Tidy up variables in VM, probably fixes subtle bugs.
Things get tricky when using the nlr code to catch exceptions. Need to
ensure that the variables (stack layout) in the exception handler are
the same as in the bit protected by the exception handler.
Prior to this patch there were a few bugs. 1) The constant
mp_const_MemoryError_obj was being preloaded to a specific location on
the stack at the start of the function. But this location on the stack
was being overwritten in the opcode loop (since it didn't think that
variable would ever be referenced again), and so when an exception
occurred, the variable holding the address of MemoryError was corrupt.
2) The FOR_ITER opcode detection in the exception handler used sp, which
may or may not contain the right value coming out of the main opcode
loop.
With this patch there is a clear separation of variables used in the
opcode loop and in the exception handler (should fix issue (2) above).
Furthermore, nlr_raise is no longer used in the opcode loop. Instead,
it jumps directly into the exception handler. This tells the C compiler
more about the possible code flow, and means that it should have the
same stack layout for the exception handler. This should fix issue (1)
above. Indeed, the generated (ARM) assembler has been checked explicitly,
and with 'goto exception_handler', the problem with &MemoryError is
fixed.
This may now fix problems with rge-sm, and probably many other subtle
bugs yet to show themselves. Incidentally, rge-sm now passes on
pyboard (with a reduced range of integration)!
Main lesson: nlr is tricky. Don't use nlr_push unless you know what you
are doing! Luckily, it's not used in many places. Using nlr_raise/jump
is fine.
2014-04-17 16:50:23 +01:00
RAISE ( obj2 ) ;
2014-03-26 15:36:12 +00:00
}
}
2014-04-14 16:22:44 +01:00
}
2014-03-26 15:36:12 +00:00
2014-04-14 16:22:44 +01:00
ENTRY ( MP_BC_IMPORT_NAME ) :
DECODE_QSTR ;
obj1 = POP ( ) ;
SET_TOP ( mp_import_name ( qst , obj1 , TOP ( ) ) ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_IMPORT_FROM ) :
DECODE_QSTR ;
obj1 = mp_import_from ( TOP ( ) , qst ) ;
PUSH ( obj1 ) ;
DISPATCH ( ) ;
ENTRY ( MP_BC_IMPORT_STAR ) :
mp_import_all ( POP ( ) ) ;
DISPATCH ( ) ;
ENTRY_DEFAULT :
obj1 = mp_obj_new_exception_msg ( & mp_type_NotImplementedError , " byte code not implemented " ) ;
nlr_pop ( ) ;
fastn [ 0 ] = obj1 ;
return MP_VM_RETURN_EXCEPTION ;
py: Tidy up variables in VM, probably fixes subtle bugs.
Things get tricky when using the nlr code to catch exceptions. Need to
ensure that the variables (stack layout) in the exception handler are
the same as in the bit protected by the exception handler.
Prior to this patch there were a few bugs. 1) The constant
mp_const_MemoryError_obj was being preloaded to a specific location on
the stack at the start of the function. But this location on the stack
was being overwritten in the opcode loop (since it didn't think that
variable would ever be referenced again), and so when an exception
occurred, the variable holding the address of MemoryError was corrupt.
2) The FOR_ITER opcode detection in the exception handler used sp, which
may or may not contain the right value coming out of the main opcode
loop.
With this patch there is a clear separation of variables used in the
opcode loop and in the exception handler (should fix issue (2) above).
Furthermore, nlr_raise is no longer used in the opcode loop. Instead,
it jumps directly into the exception handler. This tells the C compiler
more about the possible code flow, and means that it should have the
same stack layout for the exception handler. This should fix issue (1)
above. Indeed, the generated (ARM) assembler has been checked explicitly,
and with 'goto exception_handler', the problem with &MemoryError is
fixed.
This may now fix problems with rge-sm, and probably many other subtle
bugs yet to show themselves. Incidentally, rge-sm now passes on
pyboard (with a reduced range of integration)!
Main lesson: nlr is tricky. Don't use nlr_push unless you know what you
are doing! Luckily, it's not used in many places. Using nlr_raise/jump
is fine.
2014-04-17 16:50:23 +01:00
2014-04-17 23:24:13 +01:00
# if !MICROPY_USE_COMPUTED_GOTO
2014-04-15 08:57:01 +01:00
} // switch
2014-04-14 16:22:44 +01:00
# endif
py: Tidy up variables in VM, probably fixes subtle bugs.
Things get tricky when using the nlr code to catch exceptions. Need to
ensure that the variables (stack layout) in the exception handler are
the same as in the bit protected by the exception handler.
Prior to this patch there were a few bugs. 1) The constant
mp_const_MemoryError_obj was being preloaded to a specific location on
the stack at the start of the function. But this location on the stack
was being overwritten in the opcode loop (since it didn't think that
variable would ever be referenced again), and so when an exception
occurred, the variable holding the address of MemoryError was corrupt.
2) The FOR_ITER opcode detection in the exception handler used sp, which
may or may not contain the right value coming out of the main opcode
loop.
With this patch there is a clear separation of variables used in the
opcode loop and in the exception handler (should fix issue (2) above).
Furthermore, nlr_raise is no longer used in the opcode loop. Instead,
it jumps directly into the exception handler. This tells the C compiler
more about the possible code flow, and means that it should have the
same stack layout for the exception handler. This should fix issue (1)
above. Indeed, the generated (ARM) assembler has been checked explicitly,
and with 'goto exception_handler', the problem with &MemoryError is
fixed.
This may now fix problems with rge-sm, and probably many other subtle
bugs yet to show themselves. Incidentally, rge-sm now passes on
pyboard (with a reduced range of integration)!
Main lesson: nlr is tricky. Don't use nlr_push unless you know what you
are doing! Luckily, it's not used in many places. Using nlr_raise/jump
is fine.
2014-04-17 16:50:23 +01:00
} // for loop
2013-10-15 22:25:17 +01:00
} else {
py: Tidy up variables in VM, probably fixes subtle bugs.
Things get tricky when using the nlr code to catch exceptions. Need to
ensure that the variables (stack layout) in the exception handler are
the same as in the bit protected by the exception handler.
Prior to this patch there were a few bugs. 1) The constant
mp_const_MemoryError_obj was being preloaded to a specific location on
the stack at the start of the function. But this location on the stack
was being overwritten in the opcode loop (since it didn't think that
variable would ever be referenced again), and so when an exception
occurred, the variable holding the address of MemoryError was corrupt.
2) The FOR_ITER opcode detection in the exception handler used sp, which
may or may not contain the right value coming out of the main opcode
loop.
With this patch there is a clear separation of variables used in the
opcode loop and in the exception handler (should fix issue (2) above).
Furthermore, nlr_raise is no longer used in the opcode loop. Instead,
it jumps directly into the exception handler. This tells the C compiler
more about the possible code flow, and means that it should have the
same stack layout for the exception handler. This should fix issue (1)
above. Indeed, the generated (ARM) assembler has been checked explicitly,
and with 'goto exception_handler', the problem with &MemoryError is
fixed.
This may now fix problems with rge-sm, and probably many other subtle
bugs yet to show themselves. Incidentally, rge-sm now passes on
pyboard (with a reduced range of integration)!
Main lesson: nlr is tricky. Don't use nlr_push unless you know what you
are doing! Luckily, it's not used in many places. Using nlr_raise/jump
is fine.
2014-04-17 16:50:23 +01:00
exception_handler :
2013-10-15 22:25:17 +01:00
// exception occurred
2014-03-26 18:37:06 +00:00
// check if it's a StopIteration within a for block
if ( * save_ip = = MP_BC_FOR_ITER & & mp_obj_is_subclass_fast ( mp_obj_get_type ( nlr . ret_val ) , & mp_type_StopIteration ) ) {
py: Tidy up variables in VM, probably fixes subtle bugs.
Things get tricky when using the nlr code to catch exceptions. Need to
ensure that the variables (stack layout) in the exception handler are
the same as in the bit protected by the exception handler.
Prior to this patch there were a few bugs. 1) The constant
mp_const_MemoryError_obj was being preloaded to a specific location on
the stack at the start of the function. But this location on the stack
was being overwritten in the opcode loop (since it didn't think that
variable would ever be referenced again), and so when an exception
occurred, the variable holding the address of MemoryError was corrupt.
2) The FOR_ITER opcode detection in the exception handler used sp, which
may or may not contain the right value coming out of the main opcode
loop.
With this patch there is a clear separation of variables used in the
opcode loop and in the exception handler (should fix issue (2) above).
Furthermore, nlr_raise is no longer used in the opcode loop. Instead,
it jumps directly into the exception handler. This tells the C compiler
more about the possible code flow, and means that it should have the
same stack layout for the exception handler. This should fix issue (1)
above. Indeed, the generated (ARM) assembler has been checked explicitly,
and with 'goto exception_handler', the problem with &MemoryError is
fixed.
This may now fix problems with rge-sm, and probably many other subtle
bugs yet to show themselves. Incidentally, rge-sm now passes on
pyboard (with a reduced range of integration)!
Main lesson: nlr is tricky. Don't use nlr_push unless you know what you
are doing! Luckily, it's not used in many places. Using nlr_raise/jump
is fine.
2014-04-17 16:50:23 +01:00
const byte * ip = save_ip + 1 ;
machine_uint_t unum ;
2014-03-26 18:37:06 +00:00
DECODE_ULABEL ; // the jump offset if iteration finishes; for labels are always forward
py: Tidy up variables in VM, probably fixes subtle bugs.
Things get tricky when using the nlr code to catch exceptions. Need to
ensure that the variables (stack layout) in the exception handler are
the same as in the bit protected by the exception handler.
Prior to this patch there were a few bugs. 1) The constant
mp_const_MemoryError_obj was being preloaded to a specific location on
the stack at the start of the function. But this location on the stack
was being overwritten in the opcode loop (since it didn't think that
variable would ever be referenced again), and so when an exception
occurred, the variable holding the address of MemoryError was corrupt.
2) The FOR_ITER opcode detection in the exception handler used sp, which
may or may not contain the right value coming out of the main opcode
loop.
With this patch there is a clear separation of variables used in the
opcode loop and in the exception handler (should fix issue (2) above).
Furthermore, nlr_raise is no longer used in the opcode loop. Instead,
it jumps directly into the exception handler. This tells the C compiler
more about the possible code flow, and means that it should have the
same stack layout for the exception handler. This should fix issue (1)
above. Indeed, the generated (ARM) assembler has been checked explicitly,
and with 'goto exception_handler', the problem with &MemoryError is
fixed.
This may now fix problems with rge-sm, and probably many other subtle
bugs yet to show themselves. Incidentally, rge-sm now passes on
pyboard (with a reduced range of integration)!
Main lesson: nlr is tricky. Don't use nlr_push unless you know what you
are doing! Luckily, it's not used in many places. Using nlr_raise/jump
is fine.
2014-04-17 16:50:23 +01:00
* ip_in_out = ip + unum ; // jump to after for-block
* sp_in_out = save_sp - 1 ; // pop the exhausted iterator
2014-03-26 18:37:06 +00:00
goto outer_dispatch_loop ; // continue with dispatch loop
}
2014-01-18 23:24:36 +00:00
// set file and line number that the exception occurred at
2014-01-30 11:49:18 +00:00
// TODO: don't set traceback for exceptions re-raised by END_FINALLY.
// But consider how to handle nested exceptions.
2014-04-04 11:52:59 +01:00
// TODO need a better way of not adding traceback to constant objects (right now, just GeneratorExit_obj and MemoryError_obj)
if ( mp_obj_is_exception_instance ( nlr . ret_val ) & & nlr . ret_val ! = & mp_const_GeneratorExit_obj & & nlr . ret_val ! = & mp_const_MemoryError_obj ) {
2014-01-18 23:24:36 +00:00
machine_uint_t code_info_size = code_info [ 0 ] | ( code_info [ 1 ] < < 8 ) | ( code_info [ 2 ] < < 16 ) | ( code_info [ 3 ] < < 24 ) ;
2014-01-19 11:48:48 +00:00
qstr source_file = code_info [ 4 ] | ( code_info [ 5 ] < < 8 ) | ( code_info [ 6 ] < < 16 ) | ( code_info [ 7 ] < < 24 ) ;
qstr block_name = code_info [ 8 ] | ( code_info [ 9 ] < < 8 ) | ( code_info [ 10 ] < < 16 ) | ( code_info [ 11 ] < < 24 ) ;
2014-01-18 23:24:36 +00:00
machine_uint_t source_line = 1 ;
machine_uint_t bc = save_ip - code_info - code_info_size ;
2014-01-19 11:48:48 +00:00
//printf("find %lu %d %d\n", bc, code_info[12], code_info[13]);
2014-01-25 11:43:20 +00:00
for ( const byte * ci = code_info + 12 ; * ci & & bc > = ( ( * ci ) & 31 ) ; ci + + ) {
bc - = * ci & 31 ;
source_line + = * ci > > 5 ;
2014-01-18 23:24:36 +00:00
}
2014-01-19 12:38:49 +00:00
mp_obj_exception_add_traceback ( nlr . ret_val , source_file , source_line , block_name ) ;
2014-01-18 23:24:36 +00:00
}
2013-12-29 16:54:59 +00:00
while ( currently_in_except_block ) {
// nested exception
2014-03-22 11:49:31 +00:00
assert ( exc_sp > = exc_stack ) ;
2013-12-29 16:54:59 +00:00
// TODO make a proper message for nested exception
// at the moment we are just raising the very last exception (the one that caused the nested exception)
// move up to previous exception handler
2014-03-29 21:16:27 +00:00
POP_EXC_BLOCK ( ) ;
2013-12-29 16:54:59 +00:00
}
2014-03-22 11:49:31 +00:00
if ( exc_sp > = exc_stack ) {
2013-12-29 16:54:59 +00:00
// set flag to indicate that we are now handling an exception
currently_in_except_block = 1 ;
2013-10-15 22:25:17 +01:00
// catch exception and pass to byte code
py: Tidy up variables in VM, probably fixes subtle bugs.
Things get tricky when using the nlr code to catch exceptions. Need to
ensure that the variables (stack layout) in the exception handler are
the same as in the bit protected by the exception handler.
Prior to this patch there were a few bugs. 1) The constant
mp_const_MemoryError_obj was being preloaded to a specific location on
the stack at the start of the function. But this location on the stack
was being overwritten in the opcode loop (since it didn't think that
variable would ever be referenced again), and so when an exception
occurred, the variable holding the address of MemoryError was corrupt.
2) The FOR_ITER opcode detection in the exception handler used sp, which
may or may not contain the right value coming out of the main opcode
loop.
With this patch there is a clear separation of variables used in the
opcode loop and in the exception handler (should fix issue (2) above).
Furthermore, nlr_raise is no longer used in the opcode loop. Instead,
it jumps directly into the exception handler. This tells the C compiler
more about the possible code flow, and means that it should have the
same stack layout for the exception handler. This should fix issue (1)
above. Indeed, the generated (ARM) assembler has been checked explicitly,
and with 'goto exception_handler', the problem with &MemoryError is
fixed.
This may now fix problems with rge-sm, and probably many other subtle
bugs yet to show themselves. Incidentally, rge-sm now passes on
pyboard (with a reduced range of integration)!
Main lesson: nlr is tricky. Don't use nlr_push unless you know what you
are doing! Luckily, it's not used in many places. Using nlr_raise/jump
is fine.
2014-04-17 16:50:23 +01:00
* ip_in_out = exc_sp - > handler ;
mp_obj_t * sp = MP_TAGPTR_PTR ( exc_sp - > val_sp ) ;
2014-03-30 00:54:48 +00:00
// save this exception in the stack so it can be used in a reraise, if needed
exc_sp - > prev_exc = nlr . ret_val ;
2013-10-15 23:46:01 +01:00
// push(traceback, exc-val, exc-type)
2013-12-21 18:17:45 +00:00
PUSH ( mp_const_none ) ;
2013-10-15 23:46:01 +01:00
PUSH ( nlr . ret_val ) ;
2014-03-29 00:52:17 +00:00
PUSH ( mp_obj_get_type ( nlr . ret_val ) ) ;
py: Tidy up variables in VM, probably fixes subtle bugs.
Things get tricky when using the nlr code to catch exceptions. Need to
ensure that the variables (stack layout) in the exception handler are
the same as in the bit protected by the exception handler.
Prior to this patch there were a few bugs. 1) The constant
mp_const_MemoryError_obj was being preloaded to a specific location on
the stack at the start of the function. But this location on the stack
was being overwritten in the opcode loop (since it didn't think that
variable would ever be referenced again), and so when an exception
occurred, the variable holding the address of MemoryError was corrupt.
2) The FOR_ITER opcode detection in the exception handler used sp, which
may or may not contain the right value coming out of the main opcode
loop.
With this patch there is a clear separation of variables used in the
opcode loop and in the exception handler (should fix issue (2) above).
Furthermore, nlr_raise is no longer used in the opcode loop. Instead,
it jumps directly into the exception handler. This tells the C compiler
more about the possible code flow, and means that it should have the
same stack layout for the exception handler. This should fix issue (1)
above. Indeed, the generated (ARM) assembler has been checked explicitly,
and with 'goto exception_handler', the problem with &MemoryError is
fixed.
This may now fix problems with rge-sm, and probably many other subtle
bugs yet to show themselves. Incidentally, rge-sm now passes on
pyboard (with a reduced range of integration)!
Main lesson: nlr is tricky. Don't use nlr_push unless you know what you
are doing! Luckily, it's not used in many places. Using nlr_raise/jump
is fine.
2014-04-17 16:50:23 +01:00
* sp_in_out = sp ;
2013-12-29 16:54:59 +00:00
2013-10-15 22:25:17 +01:00
} else {
2014-02-15 22:55:00 +00:00
// propagate exception to higher level
// TODO what to do about ip and sp? they don't really make sense at this point
fastn [ 0 ] = nlr . ret_val ; // must put exception here because sp is invalid
return MP_VM_RETURN_EXCEPTION ;
2013-10-15 22:25:17 +01:00
}
2013-10-04 19:53:11 +01:00
}
}
}