Crude try-except working.

This commit is contained in:
Damien 2013-10-15 23:46:01 +01:00
parent ce89a21ea4
commit c9f91976e1
2 changed files with 26 additions and 8 deletions

32
py/vm.c
View File

@ -17,6 +17,8 @@
// args are in reverse order in array
py_obj_t py_execute_byte_code(const byte *code, uint len, const py_obj_t *args, uint n_args) {
// careful: be sure to declare volatile any variables read in the exception handler (written is ok, I think)
const byte *ip = code;
py_obj_t stack[10];
py_obj_t *sp = &stack[10]; // stack grows down, sp points to top of stack
@ -27,6 +29,10 @@ py_obj_t py_execute_byte_code(const byte *code, uint len, const py_obj_t *args,
py_obj_t fast0 = NULL, fast1 = NULL, fast2 = NULL, fastn[4] = {NULL, NULL, NULL, NULL};
nlr_buf_t nlr;
// on the exception stack we store (ip, sp) for each block
machine_uint_t exc_stack[8];
machine_uint_t *volatile exc_sp = &exc_stack[-1]; // stack grows up, exc_sp points to top of stack
// init args
for (int i = 0; i < n_args; i++) {
if (i == 0) {
@ -203,8 +209,9 @@ py_obj_t py_execute_byte_code(const byte *code, uint len, const py_obj_t *args,
*/
case PYBC_SETUP_EXCEPT:
// push_block(PYBC_SETUP_EXCEPT, code + unum, sp)
assert(0);
DECODE_UINT;
*++exc_sp = (machine_uint_t)code + unum;
*++exc_sp = (machine_uint_t)sp;
break;
case PYBC_END_FINALLY:
@ -237,8 +244,14 @@ py_obj_t py_execute_byte_code(const byte *code, uint len, const py_obj_t *args,
break;
case PYBC_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(0);
assert(exc_sp >= &exc_stack[0]);
//sp = (py_obj_t*)(*exc_sp--);
//exc_sp--; // discard ip
exc_sp -= 2;
//sp += 3; // pop 3 exception values
assert(sp <= &stack[10]);
break;
case PYBC_BINARY_OP:
@ -303,6 +316,8 @@ py_obj_t py_execute_byte_code(const byte *code, uint len, const py_obj_t *args,
case PYBC_RETURN_VALUE:
nlr_pop();
assert(sp == &stack[9]);
assert(exc_sp == &exc_stack[-1]);
return *sp;
default:
@ -316,11 +331,14 @@ py_obj_t py_execute_byte_code(const byte *code, uint len, const py_obj_t *args,
} else {
// exception occurred
if (0) {
if (exc_sp >= &exc_stack[0]) {
// catch exception and pass to byte code
//ip = pop
//sp = pop
//push(traceback, exc-val, exc-type)
sp = (py_obj_t*)(exc_sp[0]);
ip = (const byte*)(exc_sp[-1]);
// push(traceback, exc-val, exc-type)
PUSH(py_const_none);
PUSH(nlr.ret_val);
PUSH(py_const_none);
} else {
// re-raise exception
nlr_jump(nlr.ret_val);

View File

@ -1,7 +1,7 @@
// options to control how Micro Python is built
#define MICROPY_ENABLE_FLOAT (1)
#define MICROPY_EMIT_CPYTHON (1)
#define MICROPY_EMIT_CPYTHON (0)
#define MICROPY_EMIT_X64 (0)
#define MICROPY_EMIT_THUMB (0)
#define MICROPY_EMIT_INLINE_THUMB (0)