/*
* GC initialization.
*/
extern bool GC_init(void)
{
if (gc_inited)
return true; // Already initialised.
gc_debug("initializing");
// Check that we are in a 64-bit environment.
if (sizeof(void *) != sizeof(uint64_t) ||
sizeof(double) != sizeof(uint64_t))
{
errno = ENOEXEC;
return false;
}
// Find the stack:
gc_stackbottom = gc_get_stackbottom();
// Reserve a large chunk of the virtual address space for the GC.
void *gc_memory = gc_get_memory();
if (gc_memory != GC_MEMORY)
goto init_error;
// Initialize all of the region information structures.
for (size_t i = 0; i < GC_NUM_REGIONS; i++)
{
void *startptr = GC_MEMORY + i*GC_REGION_SIZE;
size_t unit = gc_index_unit(i);
size_t size = (i - gc_unit_offset(unit))*unit + unit;
uintptr_t offset = (uintptr_t)startptr % size;
if (offset != 0)
startptr += size - offset;
gc_region_t region = __gc_regions + i;
region->size = size;
region->inv_size = (UINT64_MAX / size) + 1;
region->freelist = NULL;
region->startptr = startptr;
region->endptr = startptr + GC_REGION_SIZE;
region->freeptr = startptr;
region->protectptr = startptr;
region->markstartptr = startptr;
region->markendptr = startptr;
region->markptr = NULL;
region->startidx = gc_objidx(startptr);
}
// Reserve virtual space for the mark stack.
gc_markstack = gc_get_mark_memory(GC_MARK_STACK_SIZE);
if (gc_markstack == NULL)
goto init_error;
gc_inited = true;
return true;
int saved_errno;
init_error:
saved_errno = errno;
if (gc_markstack != NULL)
gc_free_memory(gc_markstack, GC_MARK_STACK_SIZE);
if (gc_memory != NULL)
gc_free_memory(GC_MEMORY, GC_NUM_REGIONS*GC_REGION_SIZE);
errno = saved_errno;
return false;
}
/*
* Class: java_lang_VMMemoryManager
* Method: getFreeMemory
* Signature: ()J
*/
JNIEXPORT jlong JNICALL Java_java_lang_VMMemoryManager_getFreeMemory
(JNIEnv *, jclass)
{
return gc_free_memory();
}
