Function je_xallocx

BeefRT/JEMalloc/src/jemalloc.c:3752–3839

}

JEMALLOC_EXPORT size_t JEMALLOC_NOTHROW
je_xallocx(void *ptr, size_t size, size_t extra, int flags) {
	tsd_t *tsd;
	size_t usize, old_usize;
	size_t alignment = MALLOCX_ALIGN_GET(flags);
	bool zero = zero_get(MALLOCX_ZERO_GET(flags), /* slow */ true);

	LOG("core.xallocx.entry", "ptr: %p, size: %zu, extra: %zu, "
	    "flags: %d", ptr, size, extra, flags);

	assert(ptr != NULL);
	assert(size != 0);
	assert(SIZE_T_MAX - size >= extra);
	assert(malloc_initialized() || IS_INITIALIZER);
	tsd = tsd_fetch();
	check_entry_exit_locking(tsd_tsdn(tsd));

	/*
	 * old_edata is only for verifying that xallocx() keeps the edata_t
	 * object associated with the ptr (though the content of the edata_t
	 * object can be changed).
	 */
	edata_t *old_edata = emap_edata_lookup(tsd_tsdn(tsd),
	    &arena_emap_global, ptr);

	emap_alloc_ctx_t alloc_ctx;
	emap_alloc_ctx_lookup(tsd_tsdn(tsd), &arena_emap_global, ptr,
	    &alloc_ctx);
	assert(alloc_ctx.szind != SC_NSIZES);
	old_usize = sz_index2size(alloc_ctx.szind);
	assert(old_usize == isalloc(tsd_tsdn(tsd), ptr));
	/*
	 * The API explicitly absolves itself of protecting against (size +
	 * extra) numerical overflow, but we may need to clamp extra to avoid
	 * exceeding SC_LARGE_MAXCLASS.
	 *
	 * Ordinarily, size limit checking is handled deeper down, but here we
	 * have to check as part of (size + extra) clamping, since we need the
	 * clamped value in the above helper functions.
	 */
	if (unlikely(size > SC_LARGE_MAXCLASS)) {
		usize = old_usize;
		goto label_not_resized;
	}
	if (unlikely(SC_LARGE_MAXCLASS - size < extra)) {
		extra = SC_LARGE_MAXCLASS - size;
	}

	if (config_prof && opt_prof) {
		usize = ixallocx_prof(tsd, ptr, old_usize, size, extra,
		    alignment, zero, &alloc_ctx);
	} else {
		usize = ixallocx_helper(tsd_tsdn(tsd), ptr, old_usize, size,
		    extra, alignment, zero);
	}

	/*
	 * xallocx() should keep using the same edata_t object (though its