// Ultra-mode (SLL-only) helpers
// Ultra batch overrides via env: HAKMEM_TINY_ULTRA_BATCH_C{0..7}
static int g_ultra_batch_override[TINY_NUM_CLASSES] = {0};
static int g_ultra_sll_cap_override[TINY_NUM_CLASSES] = {0};

static inline int ultra_batch_for_class(int class_idx) {
    int ov = g_ultra_batch_override[class_idx];
    if (ov > 0) return ov;
    switch (class_idx) {
        case 0: return 64;            // 8B
        case 1: return 96;            // 16B（A/B最良）
        case 2: return 96;            // 32B（A/B最良）
        case 3: return 224;           // 64B（A/B最良）
        case 4: return 96;            // 128B (promote front refill a bit)
        case 5: return 64;            // 256B (promote front refill)
        case 6: return 64;            // 512B (promote front refill)
        default: return 32;           // 1024B and others
    }
}