compiler-codegen/nova_rt/alloc.c - main - nv-lang/nova

compiler-codegen/nova_rt/alloc.c
75 строк3 KB
Evgeniy Golovin
feat(269-278): bdwgc extra/gc.c amalgamation fallback + fflush before abort
02 авг 2026, 18:21
02 авг 2026, 18:216708fda
/* nova_rt/alloc.c — Phase-0 implementation: plain malloc, no GC.
 * To switch GC: replace this file only. The codegen never calls malloc directly.
 *
 * Contract: nova_alloc MUST return zeroed memory. Codegen assumes zero-init
 * (see emit_c.rs: record/closure/spawn-context fields set by assignment only).
 * Use calloc, not malloc. */

#include "alloc.h"
#include <stdlib.h>
#include <stdio.h>

static size_t _alloc_count = 0;
static size_t _free_count  = 0;

void nova_gc_init(void)     { _alloc_count = 0; _free_count = 0; }
void nova_gc_shutdown(void) {}

void* nova_alloc(size_t size) {
    void* p = calloc(1, size);
    if (!p) {
        fprintf(stderr, "nova: out of memory\n");
        /* #278 [M-nova-alloc-abort-no-fflush]: flush BOTH streams before
         * abort() — stdout is buffered (fully-buffered when redirected to a
         * file/pipe, the common case for test-runner children), so any
         * println() output the program already produced is still sitting
         * in libc's buffer when abort() tears the process down; without an
         * explicit fflush it's lost, hiding the last lines printed before
         * the crash and costing extra repro runs to diagnose (see #109). */
        fflush(stdout);
        fflush(stderr);
        abort();
    }
    _alloc_count++;
    return p;
}

/* Plan 83.4.5.8 (2026-05-24): uncollectable allocation. Под malloc-backend
 * identical to nova_alloc + free. */
void* nova_alloc_uncollectable(size_t size) {
    void* p = calloc(1, size);
    if (!p) {
        fprintf(stderr, "nova: out of memory (uncollectable)\n");
        /* #278: see nova_alloc's matching comment above. */
        fflush(stdout);
        fflush(stderr);
        abort();
    }
    _alloc_count++;
    return p;
}

void nova_free_uncollectable(void* ptr) {
    if (!ptr) return;
    free(ptr);
    _free_count++;
}

/* Plan 152.4: no-op under malloc — nothing is collected, so static-storage
 * pointers never need explicit rooting. */
void nova_gc_add_root(void* lo, void* hi) { (void)lo; (void)hi; }

/* RC stubs — no-ops in malloc mode (no free, so free_count stays 0). */
void nova_retain(void* ptr)  { (void)ptr; }
void nova_release(void* ptr) { (void)ptr; }

size_t nova_gc_alloc_count(void) { return _alloc_count; }
size_t nova_gc_free_count(void)  { return _free_count; }
size_t nova_gc_live_count(void)  { return _alloc_count - _free_count; }
void   nova_gc_reset_stats(void) { _alloc_count = 0; _free_count = 0; }

/* Plan 32: introspection — under plain malloc honest "not supported". */
size_t   nova_gc_heap_size(void) { return 0; }
void     nova_gc_collect(void)   { /* no-op: no GC to invoke */ }
/* Plan 57.C.2: under malloc — нет collect-cycle, последний pause всегда 0. */
uint64_t nova_gc_last_pause_ns(void) { return 0; }