VM: use an std::vector instead of a fixed-size buffer for GC roots

vm/data_gc.cpp

@@ -266,19 +266,21 @@ static void copy_stack_elements(segment *region, cell top)
 
 static void copy_registered_locals()
 {
-	cell scan = gc_locals_region->start;
+	std::vector<cell>::const_iterator iter = gc_locals.begin();
+	std::vector<cell>::const_iterator end = gc_locals.end();
 
-	for(; scan <= gc_locals; scan += sizeof(cell))
-		copy_handle(*(cell **)scan);
+	for(; iter < end; iter++)
+		copy_handle((cell *)(*iter));
 }
 
 static void copy_registered_bignums()
 {
-	cell scan = gc_bignums_region->start;
+	std::vector<cell>::const_iterator iter = gc_bignums.begin();
+	std::vector<cell>::const_iterator end = gc_bignums.end();
 
-	for(; scan <= gc_bignums; scan += sizeof(cell))
+	for(; iter < end; iter++)
 	{
-		bignum **handle = *(bignum ***)scan;
+		bignum **handle = (bignum **)(*iter);
 		bignum *pointer = *handle;
 
 		if(pointer)
@@ -683,12 +685,12 @@ PRIMITIVE(become)
 VM_ASM_API void inline_gc(cell *gc_roots_base, cell gc_roots_size)
 {
 	for(cell i = 0; i < gc_roots_size; i++)
-		gc_local_push((cell)&gc_roots_base[i]);
+		gc_locals.push_back((cell)&gc_roots_base[i]);
 
 	garbage_collection(data->nursery(),false,0);
 
 	for(cell i = 0; i < gc_roots_size; i++)
-		gc_local_pop();
+		gc_locals.pop_back();
 }
 
 }

vm/data_heap.cpp

@@ -183,15 +183,7 @@ void init_data_heap(cell gens,
 	bool secure_gc_)
 {
 	set_data_heap(alloc_data_heap(gens,young_size,aging_size,tenured_size));
-
-	gc_locals_region = alloc_segment(getpagesize());
-	gc_locals = gc_locals_region->start - sizeof(cell);
-
-	gc_bignums_region = alloc_segment(getpagesize());
-	gc_bignums = gc_bignums_region->start - sizeof(cell);
-
 	secure_gc = secure_gc_;
-
 	init_data_gc();
 }
 

vm/errors.cpp

@@ -41,8 +41,8 @@ void throw_error(cell error, stack_frame *callstack_top)
 		gc_off = false;
 
 		/* Reset local roots */
-		gc_locals = gc_locals_region->start - sizeof(cell);
-		gc_bignums = gc_bignums_region->start - sizeof(cell);
+		gc_locals.clear();
+		gc_bignums.clear();
 
 		/* If we had an underflow or overflow, stack pointers might be
 		out of bounds */

vm/local_roots.cpp

@@ -3,10 +3,8 @@
 namespace factor
 {
 
-segment *gc_locals_region;
-cell gc_locals;
+std::vector<cell> gc_locals;
 
-segment *gc_bignums_region;
-cell gc_bignums;
+std::vector<cell> gc_bignums;
 
 }

vm/local_roots.hpp

@@ -4,15 +4,12 @@ namespace factor
 /* If a runtime function needs to call another function which potentially
 allocates memory, it must wrap any local variable references to Factor
 objects in gc_root instances */
-extern segment *gc_locals_region;
-extern cell gc_locals;
-
-DEFPUSHPOP(gc_local_,gc_locals)
+extern std::vector<cell> gc_locals;
 
 template <typename T>
 struct gc_root : public tagged<T>
 {
-	void push() { check_tagged_pointer(tagged<T>::value()); gc_local_push((cell)this); }
+	void push() { check_tagged_pointer(tagged<T>::value()); gc_locals.push_back((cell)this); }
 	
 	explicit gc_root(cell value_) : tagged<T>(value_) { push(); }
 	explicit gc_root(T *value_) : tagged<T>(value_) { push(); }
@@ -22,19 +19,15 @@ struct gc_root : public tagged<T>
 
 	~gc_root() {
 #ifdef FACTOR_DEBUG
-		cell old = gc_local_pop();
-		assert(old == (cell)this);
+		assert(gc_locals.back() == (cell)this);
 #else
-		gc_local_pop();
+		gc_locals.pop_back();
 #endif
 	}
 };
 
 /* A similar hack for the bignum implementation */
-extern segment *gc_bignums_region;
-extern cell gc_bignums;
-
-DEFPUSHPOP(gc_bignum_,gc_bignums)
+extern std::vector<cell> gc_bignums;
 
 struct gc_bignum
 {
@@ -43,10 +36,15 @@ struct gc_bignum
 	gc_bignum(bignum **addr_) : addr(addr_) {
 		if(*addr_)
 			check_data_pointer(*addr_);
-		gc_bignum_push((cell)addr);
+		gc_bignums.push_back((cell)addr);
 	}
 
-	~gc_bignum() { assert((cell)addr == gc_bignum_pop()); }
+	~gc_bignum() {
+#ifdef FACTOR_DEBUG
+		assert(gc_bignums.back() == (cell)addr);
+#endif
+		gc_bignums.pop_back();
+	}
 };
 
 #define GC_BIGNUM(x) gc_bignum x##__gc_root(&x)

vm/master.hpp

@@ -21,6 +21,8 @@
 #include <time.h>
 
 /* C++ headers */
+#include <vector>
+
 #if __GNUC__ == 4
         #include <tr1/unordered_map>
         #define unordered_map std::tr1::unordered_map