brl.mod/blitz.mod/blitz_gc.c

#include "blitz.h"

#ifdef __APPLE__
#include <mach-o/getsect.h>
#endif

#ifdef _WIN32
#ifdef __x86_64__
extern void *__bss_end__;
extern void *__data_start__;
#else
extern void *_bss_end__;
extern void *_data_start__;
#endif
#endif

#ifdef __linux__
#ifdef __ANDROID__
extern int __data_start[];
extern int _end[];
#else
extern void *__data_start;
extern void *_end;
#endif
#endif

#ifdef BBCC_ALLOCCOUNT
BBUInt64 bbGCAllocCount = 0;
#endif

static bb_mutex_t * bbReleaseRetainGuard = 0;

static void gc_finalizer( void *mem,void *pool ){
	((BBGCPool*)pool)->free( (BBGCMem*)mem );
}

static void gc_warn_proc( char *msg,GC_word arg ){
	/*printf(msg,arg);fflush(stdout);*/
}

static bb_mutex_t *bb_create_mutex(){
	bb_mutex_t *mutex=malloc( sizeof(bb_mutex_t) );
	if( bb_mutex_init( mutex ) ) return mutex;
	free( mutex );
	return 0;
}

void bbGCStartup( void *spTop ){
/*	GC_set_no_dls(1);
	GC_clear_roots();
#ifdef _WIN32
#ifdef __x86_64__
	GC_add_roots(&__data_start__, &__bss_end__);
#else
	GC_add_roots(&_data_start__, &_bss_end__);
#endif
#endif

#ifdef __APPLE__
#ifndef __LP64__
	struct segment_command * seg;
#else
	struct segment_command_64 * seg;
#endif
	
	seg = getsegbyname( "__DATA" );

//	GC_add_roots((void*)seg->vmaddr, (void*)(seg->vmaddr + seg->vmsize));
#endif

#ifdef __linux__
	GC_add_roots(&__data_start, &_end);
#endif
*/
	GC_INIT();
#if !defined(__EMSCRIPTEN__) && !defined(__SWITCH__)
#ifdef GC_THREADS
	GC_allow_register_threads();
#endif
#endif
	GC_set_warn_proc( gc_warn_proc );
	bbReleaseRetainGuard = bb_create_mutex();
}

BBGCMem *bbGCAlloc( unsigned int sz,BBGCPool *pool ){
	GC_finalization_proc ofn;
	void *ocd;
	BBGCMem *q=(BBGCMem*) GC_MALLOC( sz );
	#ifdef BBCC_ALLOCCOUNT
	++bbGCAllocCount;
	#endif
	q->pool=pool;
	//q->refs=-1;
	GC_REGISTER_FINALIZER_NO_ORDER( q,gc_finalizer,pool,&ofn,&ocd );
	return q;
}

BBObject * bbGCAllocObject( unsigned int sz,BBClass *clas,int flags ){
	BBObject *q;
	if( flags & BBGC_ATOMIC ){
		q=(BBObject*)GC_MALLOC_ATOMIC( sz );
	}else{
		q=(BBObject*)GC_MALLOC( sz );
	}
	#ifdef BBCC_ALLOCCOUNT
	++bbGCAllocCount;
	#endif
	q->clas=clas;
	
	if (bbCountInstances) {
		bbAtomicAdd(&clas->instance_count, 1);
	}
	
	if( (flags & BBGC_FINALIZE) || bbCountInstances ){
		GC_finalization_proc ofn;
		void *ocd;
		GC_REGISTER_FINALIZER_NO_ORDER( q,gc_finalizer,clas,&ofn,&ocd );
	}
	return q;	
}

void bbGCFree( BBGCMem *q ){
}

int bbGCValidate( void *q ){
	if (GC_is_heap_ptr( q )) {
		BBClass * clas = ((BBObject*)q)->clas;
		int count;
		BBClass ** classes = bbObjectRegisteredTypes(&count);
		while (count--) {
			if (classes[count] == clas) {
				return 1;
			}
		}
		// maybe an array?
		if (clas == (BBClass *)&bbArrayClass) {
			return 1;
		}
	}
	return 0;
}

size_t bbGCCollect(){
	GC_gcollect();
	return GC_get_expl_freed_bytes_since_gc();
}

int bbGCCollectALittle() {
	return GC_collect_a_little();
}

void bbGCSetMode( int mode ){
	if (mode == 1) {
		GC_set_disable_automatic_collection(0);
	} else if (mode == 2) {
		GC_set_disable_automatic_collection(1);
	}
}

int bbGCGetMode(){
	if (GC_get_disable_automatic_collection()) {
		return 2;
	} else {
		return 1;
	}
}

void bbGCSetDebug( int debug ){
}

void bbGCSuspend(){
	GC_disable();
}

void bbGCResume(){
	GC_enable();
}

size_t bbGCMemAlloced(){
	return GC_get_heap_size();
}

static struct avl_root *retain_root = 0;

#define generic_compare(x, y) (((x) > (y)) - ((x) < (y)))

int node_compare(const void *x, const void *y) {

        struct retain_node * node_x = (struct retain_node *)x;
        struct retain_node * node_y = (struct retain_node *)y;

        return generic_compare(node_x->obj, node_y->obj);
}

void bbGCRetain( BBObject *p ) {
	struct retain_node * node = (struct retain_node *)GC_malloc_uncollectable(sizeof(struct retain_node));
	node->count = 1;
	node->obj = p;
	#ifdef BBCC_ALLOCCOUNT
	++bbGCAllocCount;
	#endif
	
	bb_mutex_lock(bbReleaseRetainGuard);
	
	struct retain_node * old_node = (struct retain_node *)avl_map(&node->link, node_compare, &retain_root);
	if (&node->link != &old_node->link) {
		// this object already exists here... increment our reference count
		old_node->count++;
		
		// unlock before free, to prevent deadlocks from finalizers.
		bb_mutex_unlock(bbReleaseRetainGuard);
		
		// delete the new node, since we don't need it
		GC_FREE(node);
		return;
	}

	bb_mutex_unlock(bbReleaseRetainGuard);
}

void bbGCRelease( BBObject *p ) {
	// create something to look up
	struct retain_node node;
	node.obj = p;
	
	bb_mutex_lock(bbReleaseRetainGuard);

	struct retain_node * found = (struct retain_node *)tree_search((struct tree_root_np *)&node, node_compare, (struct tree_root_np *)retain_root);

	if (found) {
		// found a retained object!

		found->count--;
		if (found->count <=0) {
			// remove from the tree
			avl_del(&found->link, &retain_root);
			// free the node
			found->obj = 0;

			// unlock before free, to prevent deadlocks from finalizers.
			bb_mutex_unlock(bbReleaseRetainGuard);

			GC_FREE(found);
			return;
		}
	}

	bb_mutex_unlock(bbReleaseRetainGuard);
}

int bbGCThreadIsRegistered() {
#ifdef GC_THREADS
	return GC_thread_is_registered();
#else
	return 0;
#endif
}

int bbGCRegisterMyThread() {
#ifdef GC_THREADS
	struct GC_stack_base stackBase;
	GC_get_stack_base(&stackBase);
	return GC_register_my_thread(&stackBase);
#else
	return -1;
#endif
}

int bbGCUnregisterMyThread() {
#ifdef GC_THREADS
	return GC_unregister_my_thread();
#else
	return -1;
#endif
}

void bbGCGetStats(struct GC_prof_stats_s * stats) {
	GC_get_prof_stats(stats, sizeof(struct GC_prof_stats_s));
}