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-rw-r--r--py/vm.c33
1 files changed, 14 insertions, 19 deletions
diff --git a/py/vm.c b/py/vm.c
index 7b78b5fefb..1afd8363d1 100644
--- a/py/vm.c
+++ b/py/vm.c
@@ -17,16 +17,6 @@
// top element.
// Exception stack also grows up, top element is also pointed at.
-// Exception stack entry
-typedef struct _mp_exc_stack {
- const byte *handler;
- // bit 0 is saved currently_in_except_block value
- machine_uint_t val_sp;
- // We might only have 2 interesting cases here: SETUP_EXCEPT & SETUP_FINALLY,
- // consider storing it in bit 1 of val_sp. TODO: SETUP_WITH?
- byte opcode;
-} mp_exc_stack;
-
// Exception stack unwind reasons (WHY_* in CPython-speak)
// TODO perhaps compress this to RETURN=0, JUMP>0, with number of unwinds
// left to do encoded in the JUMP number
@@ -89,8 +79,10 @@ mp_vm_return_kind_t mp_execute_byte_code(const byte *code, const mp_obj_t *args,
}
}
+ mp_exc_stack exc_stack[4];
+ mp_exc_stack *exc_sp = &exc_stack[0] - 1;
// execute the byte code
- mp_vm_return_kind_t vm_return_kind = mp_execute_byte_code_2(code, &ip, &state[n_state - 1], &sp);
+ mp_vm_return_kind_t vm_return_kind = mp_execute_byte_code_2(code, &ip, &state[n_state - 1], &sp, exc_stack, &exc_sp);
switch (vm_return_kind) {
case MP_VM_RETURN_NORMAL:
@@ -113,7 +105,10 @@ mp_vm_return_kind_t mp_execute_byte_code(const byte *code, const mp_obj_t *args,
// 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]
-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) {
+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,
+ mp_exc_stack *exc_stack,
+ mp_exc_stack **exc_sp_in_out) {
// careful: be sure to declare volatile any variables read in the exception handler (written is ok, I think)
const byte *ip = *ip_in_out;
@@ -124,8 +119,7 @@ mp_vm_return_kind_t mp_execute_byte_code_2(const byte *code_info, const byte **i
nlr_buf_t nlr;
volatile machine_uint_t currently_in_except_block = 0; // 0 or 1, to detect nested exceptions
- mp_exc_stack exc_stack[4];
- mp_exc_stack *volatile exc_sp = &exc_stack[0] - 1; // stack grows up, exc_sp points to top of stack
+ mp_exc_stack *volatile exc_sp = *exc_sp_in_out; // stack grows up, exc_sp points to top of stack
const byte *volatile save_ip = ip; // 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)
// outer exception handling loop
@@ -434,7 +428,7 @@ unwind_jump:
// matched against: SETUP_EXCEPT, SETUP_FINALLY, SETUP_WITH
case MP_BC_POP_BLOCK:
// we are exiting an exception handler, so pop the last one of the exception-stack
- assert(exc_sp >= &exc_stack[0]);
+ assert(exc_sp >= exc_stack);
currently_in_except_block = (exc_sp->val_sp & 1); // restore previous state
exc_sp--; // pop back to previous exception handler
break;
@@ -443,7 +437,7 @@ unwind_jump:
case 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[0]);
+ assert(exc_sp >= exc_stack);
assert(currently_in_except_block);
//sp = (mp_obj_t*)(*exc_sp--);
//exc_sp--; // discard ip
@@ -592,7 +586,7 @@ unwind_return:
}
nlr_pop();
*sp_in_out = sp;
- assert(exc_sp == &exc_stack[0] - 1);
+ assert(exc_sp == exc_stack - 1);
return MP_VM_RETURN_NORMAL;
case MP_BC_RAISE_VARARGS:
@@ -605,6 +599,7 @@ unwind_return:
nlr_pop();
*ip_in_out = ip;
*sp_in_out = sp;
+ *exc_sp_in_out = exc_sp;
return MP_VM_RETURN_YIELD;
case MP_BC_IMPORT_NAME:
@@ -654,7 +649,7 @@ unwind_return:
while (currently_in_except_block) {
// nested exception
- assert(exc_sp >= &exc_stack[0]);
+ assert(exc_sp >= exc_stack);
// 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)
@@ -664,7 +659,7 @@ unwind_return:
exc_sp--; // pop back to previous exception handler
}
- if (exc_sp >= &exc_stack[0]) {
+ if (exc_sp >= exc_stack) {
// set flag to indicate that we are now handling an exception
currently_in_except_block = 1;