diff options
Diffstat (limited to 'py/vm.c')
| -rw-r--r-- | py/vm.c | 66 |
1 files changed, 41 insertions, 25 deletions
@@ -10,43 +10,50 @@ #include "runtime.h" #include "bc.h" +// (value) stack grows down (to be compatible with native code when passing pointers to the stack), top element is pointed to +// exception stack grows up, top element is pointed to + #define DECODE_UINT do { unum = *ip++; if (unum > 127) { unum = ((unum & 0x3f) << 8) | (*ip++); } } while (0) #define DECODE_QSTR do { qstr = *ip++; if (qstr > 127) { qstr = ((qstr & 0x3f) << 8) | (*ip++); } } while (0) #define PUSH(val) *--sp = (val) #define POP() (*sp++) // 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) { +py_obj_t py_execute_byte_code(const byte *code, const py_obj_t *args, uint n_args) { + py_obj_t state[18]; // TODO allocate properly + // init args + for (int i = 0; i < n_args; i++) { + assert(i < 8); + state[i] = args[n_args - 1 - i]; + } + py_obj_t *sp = &state[18]; + const byte *ip = code; + if (py_execute_byte_code_2(code, &ip, &state[0], &sp)) { + // it shouldn't yield + assert(0); + } + assert(sp == &state[17]); + return *sp; +} + +// fastn has items in normal order +// sp points to top of stack which grows down +bool py_execute_byte_code_2(const byte *code, const byte **ip_in_out, py_obj_t *fastn, py_obj_t **sp_in_out) { // 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 + const byte *ip = *ip_in_out; + py_obj_t *sp = *sp_in_out; machine_uint_t unum; machine_int_t snum; qstr qstr; py_obj_t obj1, obj2; - py_obj_t fast0 = NULL, fast1 = NULL, fast2 = NULL, fastn[4] = {NULL, NULL, NULL, NULL}; + py_obj_t fast0 = fastn[0], fast1 = fastn[1], fast2 = fastn[2]; 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) { - fast0 = args[n_args - 1]; - } else if (i == 1) { - fast1 = args[n_args - 2]; - } else if (i == 2) { - fast2 = args[n_args - 3]; - } else { - assert(i - 3 < 4); - fastn[i - 3] = args[n_args - 1 - i]; - } - } - // outer exception handling loop for (;;) { if (nlr_push(&nlr) == 0) { @@ -99,7 +106,7 @@ py_obj_t py_execute_byte_code(const byte *code, uint len, const py_obj_t *args, case PYBC_LOAD_FAST_N: DECODE_UINT; - PUSH(fastn[unum - 3]); + PUSH(fastn[unum]); break; case PYBC_LOAD_NAME: @@ -141,7 +148,7 @@ py_obj_t py_execute_byte_code(const byte *code, uint len, const py_obj_t *args, case PYBC_STORE_FAST_N: DECODE_UINT; - fastn[unum - 3] = POP(); + fastn[unum] = POP(); break; case PYBC_STORE_NAME: @@ -251,7 +258,6 @@ py_obj_t py_execute_byte_code(const byte *code, uint len, const py_obj_t *args, //exc_sp--; // discard ip exc_sp -= 2; //sp += 3; // pop 3 exception values - assert(sp <= &stack[10]); break; case PYBC_BINARY_OP: @@ -330,15 +336,24 @@ 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]); + *sp_in_out = sp; assert(exc_sp == &exc_stack[-1]); - return *sp; + return false; + + case PYBC_YIELD_VALUE: + nlr_pop(); + *ip_in_out = ip; + fastn[0] = fast0; + fastn[1] = fast1; + fastn[2] = fast2; + *sp_in_out = sp; + return true; default: printf("code %p, offset %u, byte code 0x%02x not implemented\n", code, (uint)(ip - code), op); assert(0); nlr_pop(); - return py_const_none; + return false; } } @@ -355,6 +370,7 @@ py_obj_t py_execute_byte_code(const byte *code, uint len, const py_obj_t *args, PUSH(py_const_none); } else { // re-raise exception + // TODO what to do if this is a generator?? nlr_jump(nlr.ret_val); } } |