MIRROR: javascript for 🐜's, a tiny runtime with big ambitions
optimize lookups remove traverse property chain to find SLOT_VERSION
+141
-16
-1
include/config.h
-1
include/config.h
-1
include/config.h.in
-1
include/config.h.in
+19
-14
src/ant.c
+19
-14
src/ant.c
···
3060
3060
INTERN_IDX[9] = intern_string("9", 1);
3061
3061
}
3062
3062
3063
-
static void increment_version(struct js *js, jsoff_t obj_off) {
3064
-
jsval_t version_val = get_slot(js, mkval(T_OBJ, obj_off), SLOT_VERSION);
3065
-
uint32_t new_version = (vtype(version_val) == T_NUM) ? (uint32_t)tod(version_val) + 1 : 1;
3066
-
set_slot(js, mkval(T_OBJ, obj_off), SLOT_VERSION, tov((double)new_version));
3063
+
static void invalidate_prop_cache(struct js *js, jsoff_t obj_off, jsoff_t prop_off) {
3064
+
jsoff_t koff = loadoff(js, prop_off + sizeof(jsoff_t));
3065
+
jsoff_t klen = (loadoff(js, koff) >> 2) - 1;
3066
+
3067
+
const char *key = (char *)&js->mem[koff + sizeof(jsoff_t)];
3068
+
const char *interned = intern_string(key, klen);
3069
+
if (!interned) return;
3070
+
3071
+
uint32_t cache_slot = (((uintptr_t)interned >> 3) ^ obj_off) & (ANT_LIMIT_SIZE_CACHE - 1);
3072
+
intern_prop_cache_entry_t *ce = &intern_prop_cache[cache_slot];
3073
+
3074
+
if (ce->obj_off == obj_off && ce->intern_ptr == interned) {
3075
+
ce->obj_off = 0; ce->intern_ptr = NULL;
3076
+
ce->prop_off = 0; ce->obj_version = 0;
3077
+
}
3067
3078
}
3068
3079
3069
3080
static jsval_t mkprop(struct js *js, jsval_t obj, jsval_t k, jsval_t v, jsoff_t flags) {
···
3084
3095
(void)intern_string(p, klen);
3085
3096
3086
3097
jsoff_t prop_header = (b & ~(3U | FLAGMASK)) | T_PROP | flags;
3087
-
jsval_t result = mkentity(js, prop_header, buf, sizeof(buf));
3088
-
3089
-
increment_version(js, head);
3090
-
return result;
3098
+
return mkentity(js, prop_header, buf, sizeof(buf));
3091
3099
}
3092
3100
3093
3101
static inline jsval_t mkprop_fast(struct js *js, jsval_t obj, jsval_t k, jsval_t v, jsoff_t flags) {
···
3330
3338
}
3331
3339
3332
3340
saveval(js, existing + sizeof(jsoff_t) * 2, v);
3333
-
increment_version(js, (jsoff_t)vdata(obj));
3334
3341
if (vtype(obj) != T_ARR || klen == 0 || key[0] < '0' || key[0] > '9') goto done_update;
3335
3342
3336
3343
char *endptr;
···
3349
3356
jsval_t new_len = tov((double)(update_idx + 1));
3350
3357
if (len_off != 0) {
3351
3358
saveval(js, len_off + sizeof(jsoff_t) * 2, new_len);
3352
-
increment_version(js, (jsoff_t)vdata(obj));
3353
3359
} else mkprop(js, obj, len_key, new_len, 0);
3354
3360
3355
3361
done_update:
···
3397
3403
jsval_t new_len = tov((double)(idx + 1));
3398
3404
if (len_off != 0) {
3399
3405
saveval(js, len_off + sizeof(jsoff_t) * 2, new_len);
3400
-
increment_version(js, (jsoff_t)vdata(obj));
3401
3406
} else mkprop(js, obj, len_key, new_len, 0);
3402
3407
}
3403
3408
···
8533
8538
jsoff_t current = loadoff(js, target);
8534
8539
8535
8540
saveoff(js, target, (deleted_next & ~3U) | (current & (FLAGMASK | 3U)));
8536
-
increment_version(js, obj_off);
8541
+
invalidate_prop_cache(js, obj_off, prop_off);
8537
8542
js->needs_gc = true;
8538
8543
}
8539
8544
···
21558
21563
jsoff_t deleted_next = loadoff(js, prop_off) & ~FLAGMASK;
21559
21564
jsoff_t current = loadoff(js, obj_off);
21560
21565
saveoff(js, obj_off, (deleted_next & ~3U) | (current & (FLAGMASK | 3U)));
21561
-
increment_version(js, obj_off);
21566
+
invalidate_prop_cache(js, obj_off, prop_off);
21562
21567
js->needs_gc = true;
21563
21568
return true;
21564
21569
}
···
21570
21575
jsoff_t deleted_next = loadoff(js, prop_off) & ~FLAGMASK;
21571
21576
jsoff_t prev_flags = loadoff(js, prev) & FLAGMASK;
21572
21577
saveoff(js, prev, deleted_next | prev_flags);
21573
-
increment_version(js, obj_off);
21578
+
invalidate_prop_cache(js, obj_off, prop_off);
21574
21579
js->needs_gc = true;
21575
21580
return true;
21576
21581
}
+122
tests/test_property_cache_deletion.cjs
+122
tests/test_property_cache_deletion.cjs
···
1
+
// Test: Property cache invalidation on deletion
2
+
3
+
console.log("=== Test 1: Mid-chain deletion ===");
4
+
{
5
+
let obj = { a: 1, b: 2, c: 3 };
6
+
console.log("obj.b before:", obj.b); // populate cache
7
+
delete obj.b;
8
+
console.log("obj.b after delete:", obj.b); // should be undefined
9
+
console.log("PASS:", obj.b === undefined);
10
+
}
11
+
12
+
console.log("\n=== Test 2: First property deletion ===");
13
+
{
14
+
let obj = {};
15
+
obj.a = 1;
16
+
obj.b = 2;
17
+
obj.c = 3; // c is first in chain (newest)
18
+
console.log("obj.c before:", obj.c);
19
+
delete obj.c;
20
+
console.log("obj.c after delete:", obj.c);
21
+
console.log("PASS:", obj.c === undefined);
22
+
}
23
+
24
+
console.log("\n=== Test 3: Last property deletion ===");
25
+
{
26
+
let obj = {};
27
+
obj.a = 1; // a is last in chain (oldest)
28
+
obj.b = 2;
29
+
obj.c = 3;
30
+
console.log("obj.a before:", obj.a);
31
+
delete obj.a;
32
+
console.log("obj.a after delete:", obj.a);
33
+
console.log("PASS:", obj.a === undefined);
34
+
}
35
+
36
+
console.log("\n=== Test 4: Multiple deletions ===");
37
+
{
38
+
let obj = { a: 1, b: 2, c: 3, d: 4, e: 5 };
39
+
obj.b; obj.c; obj.d; // populate cache
40
+
delete obj.c;
41
+
delete obj.b;
42
+
delete obj.d;
43
+
console.log("PASS:", obj.b === undefined && obj.c === undefined && obj.d === undefined);
44
+
console.log("a still exists:", obj.a === 1);
45
+
console.log("e still exists:", obj.e === 5);
46
+
}
47
+
48
+
console.log("\n=== Test 5: Delete and re-add ===");
49
+
{
50
+
let obj = { a: 1, b: 2, c: 3 };
51
+
obj.b; // cache
52
+
delete obj.b;
53
+
console.log("after delete:", obj.b);
54
+
obj.b = 999;
55
+
console.log("after re-add:", obj.b);
56
+
console.log("PASS:", obj.b === 999);
57
+
}
58
+
59
+
console.log("\n=== Test 6: In-place update doesnt break cache ===");
60
+
{
61
+
let obj = { a: 1, b: 2, c: 3 };
62
+
obj.b; // cache
63
+
obj.b = 100; // in-place update
64
+
obj.b = 200; // another update
65
+
console.log("obj.b:", obj.b);
66
+
console.log("PASS:", obj.b === 200);
67
+
}
68
+
69
+
console.log("\n=== Test 7: Many properties stress test ===");
70
+
{
71
+
let obj = {};
72
+
for (let i = 0; i < 100; i++) {
73
+
obj["prop" + i] = i;
74
+
}
75
+
// Access some to populate cache
76
+
obj.prop50; obj.prop25; obj.prop75;
77
+
78
+
// Delete from various positions
79
+
delete obj.prop50;
80
+
delete obj.prop25;
81
+
delete obj.prop75;
82
+
delete obj.prop0; // last in chain
83
+
delete obj.prop99; // first in chain
84
+
85
+
console.log("PASS:",
86
+
obj.prop50 === undefined &&
87
+
obj.prop25 === undefined &&
88
+
obj.prop75 === undefined &&
89
+
obj.prop0 === undefined &&
90
+
obj.prop99 === undefined &&
91
+
obj.prop1 === 1 &&
92
+
obj.prop98 === 98
93
+
);
94
+
}
95
+
96
+
console.log("\n=== Test 8: Delete non-existent (should not crash) ===");
97
+
{
98
+
let obj = { a: 1 };
99
+
obj.a; // cache
100
+
delete obj.nonexistent; // should be no-op
101
+
console.log("PASS:", obj.a === 1);
102
+
}
103
+
104
+
console.log("\n=== Test 9: Repeated access after delete ===");
105
+
{
106
+
let obj = { a: 1, b: 2, c: 3 };
107
+
obj.b; obj.b; obj.b; // multiple cache hits
108
+
delete obj.b;
109
+
let results = [obj.b, obj.b, obj.b]; // multiple accesses after delete
110
+
console.log("PASS:", results.every(x => x === undefined));
111
+
}
112
+
113
+
console.log("\n=== Test 10: Array element deletion ===");
114
+
{
115
+
let arr = [1, 2, 3, 4, 5];
116
+
arr[2]; // cache
117
+
delete arr[2];
118
+
console.log("arr[2]:", arr[2]);
119
+
console.log("PASS:", arr[2] === undefined && arr.length === 5);
120
+
}
121
+
122
+
console.log("\n=== All tests complete ===");