MIRROR: javascript for 🐜's, a tiny runtime with big ambitions
add stack scanning for rooting
+109
+4
include/gc.h
+4
include/gc.h
···
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#define GC_UPDATE_ARGS ant_t *js, GC_FWD_OFF, GC_WEAK_OFF, GC_FWD_ARGS
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#define GC_OP_VAL_ARGS GC_OP_VAL, GC_CTX
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#define GC_HEAP_TYPE_MASK ( \
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(1u << T_OBJ) | (1u << T_PROP) | (1u << T_STR) | (1u << T_FUNC) | \
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(1u << T_ARR) | (1u << T_PROMISE) | (1u << T_BIGINT) | (1u << T_GENERATOR))
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void js_gc_maybe(ant_t *js);
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void js_gc_throttle(bool enabled);
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+76
src/gc.c
+76
src/gc.c
···
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#include <stdlib.h>
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#include <stdio.h>
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#include <time.h>
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#include <setjmp.h>
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#ifdef _WIN32
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#include <windows.h>
···
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return fwd_lookup(&ctx->fwd, old_off);
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}
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static inline bool gc_get_stack_bounds(void *base, uintptr_t *lo, uintptr_t *hi) {
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if (!base) return false;
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volatile uint8_t sp_marker;
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uintptr_t bp = (uintptr_t)base;
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uintptr_t sp = (uintptr_t)&sp_marker;
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if (sp < bp) { *lo = sp; *hi = bp; }
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else { *lo = bp; *hi = sp; }
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*lo &= ~(uintptr_t)7;
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*hi &= ~(uintptr_t)7;
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return true;
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}
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__attribute__((noinline))
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static void gc_scan_stack_reserve(gc_ctx_t *ctx) {
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jmp_buf jb;
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if (setjmp(jb) != 0) return;
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uintptr_t lo, hi;
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if (!gc_get_stack_bounds(ctx->js->cstk, &lo, &hi)) return;
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jsoff_t old_brk = ctx->js->brk;
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for (uintptr_t addr = lo; addr < hi; addr += sizeof(uint64_t)) {
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uint64_t w;
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memcpy(&w, (void *)addr, sizeof(w));
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if ((w >> 53) != NANBOX_PREFIX_CHK) continue;
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uint8_t type = (w >> NANBOX_TYPE_SHIFT) & NANBOX_TYPE_MASK;
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if (type > T_FFI) continue;
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if (!((1u << type) & GC_HEAP_TYPE_MASK)) continue;
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jsoff_t old_off = (jsoff_t)(w & NANBOX_DATA_MASK);
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if (old_off == 0 || old_off >= old_brk) continue;
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if (fwd_lookup(&ctx->fwd, old_off) != (jsoff_t)~0) continue;
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gc_update_val(ctx, w);
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}
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}
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__attribute__((noinline))
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static void gc_scan_stack_update(gc_ctx_t *ctx) {
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jmp_buf jb;
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if (setjmp(jb) != 0) return;
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uintptr_t lo, hi;
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if (!gc_get_stack_bounds(ctx->js->cstk, &lo, &hi)) return;
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jsoff_t old_brk = ctx->js->brk;
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for (uintptr_t addr = lo; addr < hi; addr += sizeof(uint64_t)) {
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uint64_t w;
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memcpy(&w, (void *)addr, sizeof(w));
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if ((w >> 53) != NANBOX_PREFIX_CHK) continue;
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uint8_t type = (w >> NANBOX_TYPE_SHIFT) & NANBOX_TYPE_MASK;
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if (type > T_FFI) continue;
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if (!((1u << type) & GC_HEAP_TYPE_MASK)) continue;
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jsoff_t old_off = (jsoff_t)(w & NANBOX_DATA_MASK);
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if (old_off == 0 || old_off >= old_brk) continue;
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jsoff_t new_off = fwd_lookup(&ctx->fwd, old_off);
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if (new_off == (jsoff_t)~0 || new_off == old_off) continue;
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uint64_t updated = gc_mkval(type, new_off);
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memcpy((void *)addr, &updated, sizeof(updated));
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}
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}
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size_t js_gc_compact(ant_t *js) {
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if (!js || js->brk == 0) return 0;
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if (js->brk < 2 * 1024 * 1024) return 0;
···
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&ctx
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); gc_drain_work_queue(&ctx);
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gc_scan_stack_reserve(&ctx);
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gc_drain_work_queue(&ctx);
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if (ctx.failed) {
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free(mark_bits);
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work_free(&ctx.work);
···
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gc_apply_val_callback,
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&ctx);
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gc_scan_stack_update(&ctx);
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memcpy(js->mem, new_mem, ctx.new_brk);
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js->brk = ctx.new_brk;
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+29
tests/test_gc_stress10.js
+29
tests/test_gc_stress10.js
···
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import { Screen, colors, codes, pad, truncate } from '../examples/tui/tuey.js';
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const screen = new Screen({ fullscreen: false, hideCursor: false });
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const logs = [
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{ time: '10:23:45', level: 'INFO', message: 'Application started' },
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{ time: '10:23:48', level: 'WARN', message: 'Cache directory not found, creating...' },
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{ time: '10:24:05', level: 'ERROR', message: 'Failed to load plugin: missing-plugin' },
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{ time: '10:24:06', level: 'WARN', message: 'Running with reduced functionality' },
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{ time: '10:24:10', level: 'INFO', message: 'Ready to accept connections' },
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];
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function render() {
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screen.write(2, 14, colors.bold + colors.magenta + '┌─ Recent Activity ───────────────────────┐' + codes.reset);
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for (let i = 0; i < 5; i++) {
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const log = logs[i];
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const levelColor = log.level === 'ERROR' ? colors.red : log.level === 'WARN' ? colors.yellow : colors.green;
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screen.write(2, 15 + i, colors.magenta + '│' + codes.reset);
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screen.write(4, 15 + i, `${colors.dim}${log.time}${codes.reset} ${levelColor}${log.level}${codes.reset} ${truncate(log.message, 30)}`);
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screen.write(45, 15 + i, colors.magenta + '│' + codes.reset);
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}
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screen.write(2, 20, colors.magenta + '└──────────────────────────────────────────┘' + codes.reset);
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}
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for (let frame = 0; frame < 50000; frame++) {
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render();
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}
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console.log('OK');