MIRROR: javascript for 🐜's, a tiny runtime with big ambitions
safe entry fp for engine
+57
-9
+57
-9
src/silver/engine.c
+57
-9
src/silver/engine.c
···
36
36
if (!vm) return NULL;
37
37
38
38
vm->js = js;
39
+
vm->fp = -1;
40
+
39
41
vm->stack_size = stack_size;
40
-
vm->stack = calloc((size_t)stack_size, sizeof(ant_value_t));
41
42
vm->max_frames = max_frames;
43
+
44
+
vm->suspended_entry_fp = -1;
45
+
vm->suspended_saved_fp = -1;
46
+
47
+
vm->stack = calloc((size_t)stack_size, sizeof(ant_value_t));
42
48
vm->frames = calloc((size_t)max_frames, sizeof(sv_frame_t));
43
-
if (!vm->stack || !vm->frames) { sv_vm_destroy(vm); return NULL; }
49
+
50
+
if (!vm->stack || !vm->frames) {
51
+
sv_vm_destroy(vm);
52
+
return NULL;
53
+
}
44
54
45
55
return vm;
46
56
}
···
1698
1708
1699
1709
L_AWAIT: {
1700
1710
ant_value_t await_val = vm->stack[--vm->sp];
1711
+
frame->ip = ip + 1;
1712
+
vm->suspended_entry_fp = entry_fp;
1713
+
vm->suspended_saved_fp = entry_fp - 1;
1714
+
1701
1715
ant_value_t result = sv_await_value(js, await_val);
1702
-
if (vm->suspended) {
1703
-
vm->suspended_entry_fp = entry_fp;
1704
-
vm->suspended_saved_fp = entry_fp - 1;
1705
-
frame->ip = ip + 1;
1706
-
goto sv_leave;
1716
+
if (vm->suspended) goto sv_leave;
1717
+
1718
+
vm->suspended_entry_fp = -1;
1719
+
vm->suspended_saved_fp = -1;
1720
+
1721
+
if (is_err(result)) {
1722
+
sv_err = result;
1723
+
goto sv_throw;
1707
1724
}
1708
-
if (is_err(result)) { sv_err = result; goto sv_throw; }
1725
+
1709
1726
vm->stack[vm->sp++] = result;
1710
1727
NEXT(1);
1711
1728
}
···
1726
1743
vm_result = yielded;
1727
1744
goto sv_leave;
1728
1745
}
1746
+
1729
1747
L_YIELD_STAR_INIT: {
1730
1748
uint16_t base = sv_get_u16(ip + 1);
1731
1749
ant_value_t iterable = vm->stack[--vm->sp];
···
1877
1895
if (!vm || !vm->suspended || !vm->suspended_resume_pending || vm->fp < 0)
1878
1896
return mkval(T_ERR, 0);
1879
1897
1898
+
// crash-resistance for missing frames
1899
+
if (vm->suspended_entry_fp < 0 || vm->suspended_entry_fp > vm->fp) {
1900
+
vm->suspended = false;
1901
+
vm->suspended_resume_pending = false;
1902
+
vm->suspended_resume_is_error = false;
1903
+
vm->suspended_resume_kind = SV_RESUME_NEXT;
1904
+
vm->suspended_resume_value = js_mkundef();
1905
+
vm->suspended_entry_fp = -1;
1906
+
vm->suspended_saved_fp = -1;
1907
+
1908
+
return vm->js
1909
+
? js_mkerr(vm->js, "invalid suspended entry frame")
1910
+
: mkval(T_ERR, 0);
1911
+
}
1912
+
1880
1913
int saved_fp = vm->suspended_saved_fp;
1881
1914
sv_frame_t *frame = &vm->frames[vm->fp];
1915
+
1916
+
if (!vm->js || !frame->func || !frame->ip) {
1917
+
vm->suspended = false;
1918
+
vm->suspended_resume_pending = false;
1919
+
vm->suspended_resume_is_error = false;
1920
+
vm->suspended_resume_kind = SV_RESUME_NEXT;
1921
+
vm->suspended_resume_value = js_mkundef();
1922
+
vm->suspended_entry_fp = -1;
1923
+
vm->suspended_saved_fp = -1;
1924
+
1925
+
return vm->js
1926
+
? js_mkerr(vm->js, "invalid suspended frame state")
1927
+
: mkval(T_ERR, 0);
1928
+
}
1929
+
1882
1930
ant_value_t result = sv_execute_frame(
1883
1931
vm, frame->func, frame->this, frame->super_val, NULL, frame->argc
1884
1932
);
1885
1933
1886
1934
if (!vm->suspended) {
1887
1935
vm->fp = saved_fp;
1888
-
vm->suspended_entry_fp = 0;
1936
+
vm->suspended_entry_fp = -1;
1889
1937
vm->suspended_saved_fp = -1;
1890
1938
}
1891
1939