diff --git a/quickjs.c b/quickjs.c index d6d1478..11a6367 100644 --- a/quickjs.c +++ b/quickjs.c @@ -52747,6 +52747,18 @@ static JSValue js_typed_array_toReversed(JSContext *ctx, JSValueConst this_val, return ret; } +static void slice_memcpy(uint8_t *dst, const uint8_t *src, size_t len) +{ + if (dst + len <= src || dst >= src + len) { + /* no overlap: can use memcpy */ + memcpy(dst, src, len); + } else { + /* otherwise the spec mandates byte copy */ + while (len-- != 0) + *dst++ = *src++; + } +} + static JSValue js_typed_array_slice(JSContext *ctx, JSValueConst this_val, int argc, JSValueConst *argv) { @@ -52789,9 +52801,9 @@ static JSValue js_typed_array_slice(JSContext *ctx, JSValueConst this_val, if (p1 != NULL && p->class_id == p1->class_id && typed_array_get_length(ctx, p1) >= count && typed_array_get_length(ctx, p) >= start + count) { - memcpy(p1->u.array.u.uint8_ptr, - p->u.array.u.uint8_ptr + (start << shift), - count << shift); + slice_memcpy(p1->u.array.u.uint8_ptr, + p->u.array.u.uint8_ptr + (start << shift), + count << shift); } else { for (n = 0; n < count; n++) { val = JS_GetPropertyValue(ctx, this_val, JS_NewInt32(ctx, start + n));