hakmem/core/box/hak_free_api.inc.h

// hak_free_api.inc.h — Box: hak_free_at() implementation
#ifndef HAK_FREE_API_INC_H
#define HAK_FREE_API_INC_H

// Optional route trace: print first N classification lines when enabled by env
static inline int hak_free_route_trace_on(void) {
    static int g_trace = -1;
    if (__builtin_expect(g_trace == -1, 0)) {
        const char* e = getenv("HAKMEM_FREE_ROUTE_TRACE");
        g_trace = (e && *e && *e != '0') ? 1 : 0;
    }
    return g_trace;
}
static inline int* hak_free_route_budget_ptr(void) {
    static int g_budget = 32; // first 32 frees only
    return &g_budget;
}
static inline void hak_free_route_log(const char* tag, void* p) {
    if (!hak_free_route_trace_on()) return;
    int* budget = hak_free_route_budget_ptr();
    if (*budget <= 0) return;
    (*budget)--;
    fprintf(stderr, "[FREE_ROUTE] %s ptr=%p\n", tag, p);
}

#ifndef HAKMEM_TINY_PHASE6_BOX_REFACTOR
__attribute__((always_inline))
inline
#endif
void hak_free_at(void* ptr, size_t size, hak_callsite_t site) {
#if HAKMEM_DEBUG_TIMING
    HKM_TIME_START(t0);
#endif
    (void)site; (void)size;
    if (!ptr) {
#if HAKMEM_DEBUG_TIMING
        HKM_TIME_END(HKM_CAT_HAK_FREE, t0);
#endif
        return;
    }

    // SS-first free（既定ON）
    {
        static int s_free_to_ss = -2;
        if (s_free_to_ss == -2) {
            const char* e = getenv("HAKMEM_TINY_FREE_TO_SS");
            s_free_to_ss = (e && *e) ? ((*e!='0')?1:0) : 1;
        }
        if (s_free_to_ss) {
            extern int g_use_superslab;
            if (__builtin_expect(g_use_superslab != 0, 1)) {
                SuperSlab* ss = hak_super_lookup(ptr);
                if (ss && ss->magic == SUPERSLAB_MAGIC) {
                    int sidx = slab_index_for(ss, ptr);
                    int cap = ss_slabs_capacity(ss);
                    if (__builtin_expect(sidx >= 0 && sidx < cap, 1)) { hak_free_route_log("ss_hit", ptr); hak_tiny_free(ptr); goto done; }
                }
                for (int lg=21; lg>=20; lg--) {
                    uintptr_t mask=((uintptr_t)1<<lg)-1; SuperSlab* guess=(SuperSlab*)((uintptr_t)ptr & ~mask);
                    if (guess && guess->magic==SUPERSLAB_MAGIC) { int sidx=slab_index_for(guess,ptr); int cap=ss_slabs_capacity(guess); if (sidx>=0&&sidx<cap){ hak_free_route_log("ss_guess", ptr); hak_tiny_free(ptr); goto done; }}
                }
            }
        }
    }

    // Mid/L25 headerless経路
    {
        extern int hak_pool_mid_lookup(void* ptr, size_t* out_size);
        extern void hak_pool_free_fast(void* ptr, uintptr_t site_id);
        size_t mid_sz = 0; if (hak_pool_mid_lookup(ptr, &mid_sz)) { hak_free_route_log("mid_hit", ptr); hak_pool_free_fast(ptr, (uintptr_t)site); goto done; }
    }
    {
        extern int hak_l25_lookup(void* ptr, size_t* out_size);
        extern void hak_l25_pool_free_fast(void* ptr, uintptr_t site_id);
        size_t l25_sz = 0; if (hak_l25_lookup(ptr, &l25_sz)) { hak_free_route_log("l25_hit", ptr); hkm_ace_stat_large_free(); hak_l25_pool_free_fast(ptr, (uintptr_t)site); goto done; }
    }

    // Raw header dispatch（mmap/malloc/BigCacheなど）
    {
        void* raw = (char*)ptr - HEADER_SIZE;
        AllocHeader* hdr = (AllocHeader*)raw;
        if (hdr->magic != HAKMEM_MAGIC) {
            if (g_invalid_free_log) fprintf(stderr, "[hakmem] ERROR: Invalid magic 0x%X (expected 0x%X)\n", hdr->magic, HAKMEM_MAGIC);
            // CRITICAL FIX: When magic is invalid, allocation came from LIBC (NO header)
            // Therefore ptr IS the allocated address, not raw (ptr - HEADER_SIZE)
            // MUST use __libc_free to avoid infinite recursion through free() wrapper
            if (g_invalid_free_mode) { goto done; } else { extern void __libc_free(void*); __libc_free(ptr); goto done; }
        }
        if (HAK_ENABLED_CACHE(HAKMEM_FEATURE_BIGCACHE) && hdr->class_bytes >= 2097152) {
            if (hak_bigcache_put(ptr, hdr->size, hdr->alloc_site)) goto done;
        }
        {
            static int g_bc_l25_en_free = -1; if (g_bc_l25_en_free == -1) { const char* e = getenv("HAKMEM_BIGCACHE_L25"); g_bc_l25_en_free = (e && atoi(e) != 0) ? 1 : 0; }
            if (g_bc_l25_en_free && HAK_ENABLED_CACHE(HAKMEM_FEATURE_BIGCACHE) && hdr->size >= 524288 && hdr->size < 2097152) {
                if (hak_bigcache_put(ptr, hdr->size, hdr->alloc_site)) goto done;
            }
        }
        switch (hdr->method) {
            case ALLOC_METHOD_POOL: if (HAK_ENABLED_ALLOC(HAKMEM_FEATURE_POOL)) { hkm_ace_stat_mid_free(); hak_pool_free(ptr, hdr->size, hdr->alloc_site); goto done; } break;
            case ALLOC_METHOD_L25_POOL: hkm_ace_stat_large_free(); hak_l25_pool_free(ptr, hdr->size, hdr->alloc_site); goto done;
            case ALLOC_METHOD_MALLOC:
                // CRITICAL FIX: raw was allocated with __libc_malloc, so free with __libc_free
                // Using free(raw) would go through wrapper → infinite recursion
                hak_free_route_log("malloc_hdr", ptr);
                extern void __libc_free(void*);
                __libc_free(raw);
                break;
            case ALLOC_METHOD_MMAP:
#ifdef __linux__
                if (HAK_ENABLED_MEMORY(HAKMEM_FEATURE_BATCH_MADVISE) && hdr->size >= BATCH_MIN_SIZE) { hak_batch_add(raw, hdr->size); goto done; }
                if (hkm_whale_put(raw, hdr->size) != 0) { hkm_sys_munmap(raw, hdr->size); }
#else
                // CRITICAL FIX: Same as ALLOC_METHOD_MALLOC
                extern void __libc_free(void*);
                __libc_free(raw);
#endif
                break;
            default: fprintf(stderr, "[hakmem] ERROR: Unknown allocation method: %d\n", hdr->method); break;
        }
    }

done:
#if HAKMEM_DEBUG_TIMING
    HKM_TIME_END(HKM_CAT_HAK_FREE, t0);
#endif
    return;
}

#endif // HAK_FREE_API_INC_H