1 files changed, 189 insertions, 79 deletions

diff --git a/Zend/zend_generators.c b/Zend/zend_generators.c
index f1cc09e938..33a03ce7cc 100644
--- a/Zend/zend_generators.c
+++ b/Zend/zend_generators.c
@@ -31,6 +31,71 @@ static zend_object_handlers zend_generator_handlers;
 
 static zend_object *zend_generator_create(zend_class_entry *class_type);
 
+static void zend_restore_call_stack(zend_generator *generator) /* {{{ */
+{
+	zend_execute_data *call, *new_call, *prev_call = NULL;
+
+	call = generator->frozen_call_stack;
+	do {
+		new_call = zend_vm_stack_push_call_frame(
+			(ZEND_CALL_INFO(call) & ~ZEND_CALL_ALLOCATED),
+			call->func,
+			ZEND_CALL_NUM_ARGS(call),
+			(Z_TYPE(call->This) == IS_UNDEF) ?
+				(zend_class_entry*)Z_OBJ(call->This) : NULL,
+			(Z_TYPE(call->This) != IS_UNDEF) ?
+				Z_OBJ(call->This) : NULL);
+		memcpy(((zval*)new_call) + ZEND_CALL_FRAME_SLOT, ((zval*)call) + ZEND_CALL_FRAME_SLOT, ZEND_CALL_NUM_ARGS(call) * sizeof(zval));
+		new_call->prev_execute_data = prev_call;
+		prev_call = new_call;
+
+		call = call->prev_execute_data;
+	} while (call);
+	generator->execute_data->call = prev_call;
+	efree(generator->frozen_call_stack);
+	generator->frozen_call_stack = NULL;
+}
+/* }}} */
+
+static zend_execute_data* zend_freeze_call_stack(zend_execute_data *execute_data) /* {{{ */
+{
+	size_t used_stack;
+	zend_execute_data *call, *new_call, *prev_call = NULL;
+	zval *stack;
+
+	/* calculate required stack size */
+	used_stack = 0;
+	call = EX(call);
+	do {
+		used_stack += ZEND_CALL_FRAME_SLOT + ZEND_CALL_NUM_ARGS(call);
+		call = call->prev_execute_data;
+	} while (call);
+
+	stack = emalloc(used_stack * sizeof(zval));
+
+	/* save stack, linking frames in reverse order */
+	call = EX(call);
+	do {
+		size_t frame_size = ZEND_CALL_FRAME_SLOT + ZEND_CALL_NUM_ARGS(call);
+
+		new_call = (zend_execute_data*)(stack + used_stack - frame_size);
+		memcpy(new_call, call, frame_size * sizeof(zval));
+		used_stack -= frame_size;
+		new_call->prev_execute_data = prev_call;
+		prev_call = new_call;
+
+		new_call = call->prev_execute_data;
+		zend_vm_stack_free_call_frame(call);
+		call = new_call;
+	} while (call);
+
+	execute_data->call = NULL;
+	ZEND_ASSERT(prev_call == (zend_execute_data*)stack);
+
+	return prev_call;
+}
+/* }}} */
+
 static void zend_generator_cleanup_unfinished_execution(
 		zend_generator *generator, uint32_t catch_op_num) /* {{{ */
 {
@@ -40,21 +105,10 @@ static void zend_generator_cleanup_unfinished_execution(
 		/* -1 required because we want the last run opcode, not the next to-be-run one. */
 		uint32_t op_num = execute_data->opline - execute_data->func->op_array.opcodes - 1;
 
-		/* There may be calls to zend_vm_stack_free_call_frame(), which modifies the VM stack
-		 * globals, so need to load/restore those. */
-		zend_vm_stack original_stack = EG(vm_stack);
-		original_stack->top = EG(vm_stack_top);
-		EG(vm_stack_top) = generator->stack->top;
-		EG(vm_stack_end) = generator->stack->end;
-		EG(vm_stack) = generator->stack;
-
-		zend_cleanup_unfinished_execution(execute_data, op_num, catch_op_num);
-
-		generator->stack = EG(vm_stack);
-		generator->stack->top = EG(vm_stack_top);
-		EG(vm_stack_top) = original_stack->top;
-		EG(vm_stack_end) = original_stack->end;
-		EG(vm_stack) = original_stack;
+		if (UNEXPECTED(generator->frozen_call_stack)) {
+			zend_restore_call_stack(generator);
+		}
+		zend_cleanup_unfinished_execution(execute_data, op_num, 0);
 	}
 }
 /* }}} */
@@ -64,13 +118,13 @@ ZEND_API void zend_generator_close(zend_generator *generator, zend_bool finished
 	if (EXPECTED(generator->execute_data)) {
 		zend_execute_data *execute_data = generator->execute_data;
 
-		if (execute_data->symbol_table) {
+		if (EX_CALL_INFO() & ZEND_CALL_HAS_SYMBOL_TABLE) {
 			zend_clean_and_cache_symbol_table(execute_data->symbol_table);
 		}
 		/* always free the CV's, in the symtable are only not-free'd IS_INDIRECT's */
 		zend_free_compiled_variables(execute_data);
 
-		if (Z_OBJ(execute_data->This)) {
+		if (EX_CALL_INFO() & ZEND_CALL_RELEASE_THIS) {
 			OBJ_RELEASE(Z_OBJ(execute_data->This));
 		}
 
@@ -94,7 +148,13 @@ ZEND_API void zend_generator_close(zend_generator *generator, zend_bool finished
 			OBJ_RELEASE((zend_object *) EX(func)->common.prototype);
 		}
 
-		efree(generator->stack);
+		/* Free GC buffer. GC for closed generators doesn't need an allocated buffer */
+		if (generator->gc_buffer) {
+			efree(generator->gc_buffer);
+			generator->gc_buffer = NULL;
+		}
+
+		efree(generator->execute_data);
 		generator->execute_data = NULL;
 	}
 }
@@ -194,12 +254,103 @@ static void zend_generator_free_storage(zend_object *object) /* {{{ */
 }
 /* }}} */
 
+static uint32_t calc_gc_buffer_size(zend_generator *generator) /* {{{ */
+{
+	uint32_t size = 4; /* value, key, retval, values */
+	if (generator->execute_data) {
+		zend_execute_data *execute_data = generator->execute_data;
+		zend_op_array *op_array = &EX(func)->op_array;
+
+		/* Compiled variables */
+		if (!(EX_CALL_INFO() & ZEND_CALL_HAS_SYMBOL_TABLE)) {
+			size += op_array->last_var;
+		}
+		/* Extra args */
+		if (EX_CALL_INFO() & ZEND_CALL_FREE_EXTRA_ARGS) {
+			size += EX_NUM_ARGS() - op_array->num_args;
+		}
+		size += Z_TYPE(execute_data->This) == IS_OBJECT; /* $this */
+		size += (EX_CALL_INFO() & ZEND_CALL_CLOSURE) != 0; /* Closure object */
+
+		/* Yield from root references */
+		if (generator->node.children == 0) {
+			zend_generator *child = generator, *root = generator->node.ptr.root;
+			while (root != child) {
+				child = child->node.parent;
+				size++;
+			}
+		}
+	}
+	return size;
+}
+/* }}} */
+
 static HashTable *zend_generator_get_gc(zval *object, zval **table, int *n) /* {{{ */
 {
 	zend_generator *generator = (zend_generator*) Z_OBJ_P(object);
-	*table = &generator->value;
-	*n = 3;
-	return NULL;
+	zend_execute_data *execute_data = generator->execute_data;
+	zend_op_array *op_array;
+	zval *gc_buffer;
+	uint32_t gc_buffer_size;
+
+	if (!execute_data) {
+		/* If the generator has been closed, it can only hold on to three values: The value, key
+		 * and retval. These three zvals are stored sequentially starting at &generator->value. */
+		*table = &generator->value;
+		*n = 3;
+		return NULL;
+	}
+
+	op_array = &EX(func)->op_array;
+	gc_buffer_size = calc_gc_buffer_size(generator);
+	if (generator->gc_buffer_size < gc_buffer_size) {
+		generator->gc_buffer = safe_erealloc(generator->gc_buffer, sizeof(zval), gc_buffer_size, 0);
+		generator->gc_buffer_size = gc_buffer_size;
+	}
+
+	*n = gc_buffer_size;
+	*table = gc_buffer = generator->gc_buffer;
+
+	ZVAL_COPY_VALUE(gc_buffer++, &generator->value);
+	ZVAL_COPY_VALUE(gc_buffer++, &generator->key);
+	ZVAL_COPY_VALUE(gc_buffer++, &generator->retval);
+	ZVAL_COPY_VALUE(gc_buffer++, &generator->values);
+
+	if (!(EX_CALL_INFO() & ZEND_CALL_HAS_SYMBOL_TABLE)) {
+		uint32_t i, num_cvs = EX(func)->op_array.last_var;
+		for (i = 0; i < num_cvs; i++) {
+			ZVAL_COPY_VALUE(gc_buffer++, EX_VAR_NUM(i));
+		}
+	}
+
+	if (EX_CALL_INFO() & ZEND_CALL_FREE_EXTRA_ARGS) {
+		zval *zv = EX_VAR_NUM(op_array->last_var + op_array->T);
+		zval *end = zv + (EX_NUM_ARGS() - op_array->num_args);
+		while (zv != end) {
+			ZVAL_COPY_VALUE(gc_buffer++, zv++);
+		}
+	}
+
+	if (Z_TYPE(execute_data->This) == IS_OBJECT) {
+		ZVAL_OBJ(gc_buffer++, Z_OBJ(execute_data->This));
+	}
+	if (EX_CALL_INFO() & ZEND_CALL_CLOSURE) {
+		ZVAL_OBJ(gc_buffer++, (zend_object *) EX(func)->common.prototype);
+	}
+
+	if (generator->node.children == 0) {
+		zend_generator *child = generator, *root = generator->node.ptr.root;
+		while (root != child) {
+			child = child->node.parent;
+			ZVAL_OBJ(gc_buffer++, &child->std);
+		}
+	}
+
+	if (EX_CALL_INFO() & ZEND_CALL_HAS_SYMBOL_TABLE) {
+		return execute_data->symbol_table;
+	} else {
+		return NULL;
+	}
 }
 /* }}} */
 
@@ -228,44 +379,6 @@ static zend_object *zend_generator_create(zend_class_entry *class_type) /* {{{ *
 }
 /* }}} */
 
-/* Requires globals EG(scope), EG(This) and EG(current_execute_data). */
-ZEND_API void zend_generator_create_zval(zend_execute_data *call, zend_op_array *op_array, zval *return_value) /* {{{ */
-{
-	zend_generator *generator;
-	zend_execute_data *current_execute_data;
-	zend_execute_data *execute_data;
-	zend_vm_stack current_stack = EG(vm_stack);
-
-	current_stack->top = EG(vm_stack_top);
-
-	/* Create new execution context. We have to back up and restore  EG(current_execute_data) here. */
-	current_execute_data = EG(current_execute_data);
-	execute_data = zend_create_generator_execute_data(call, op_array, return_value);
-	EG(current_execute_data) = current_execute_data;
-
-	object_init_ex(return_value, zend_ce_generator);
-
-	if (Z_OBJ(call->This)) {
-		Z_ADDREF(call->This);
-	}
-
-	/* Save execution context in generator object. */
-	generator = (zend_generator *) Z_OBJ_P(return_value);
-	generator->execute_data = execute_data;
-	generator->stack = EG(vm_stack);
-	generator->stack->top = EG(vm_stack_top);
-	EG(vm_stack_top) = current_stack->top;
-	EG(vm_stack_end) = current_stack->end;
-	EG(vm_stack) = current_stack;
-
-	/* EX(return_value) keeps pointer to zend_object (not a real zval) */
-	execute_data->return_value = (zval*)generator;
-
-	memset(&generator->execute_fake, 0, sizeof(zend_execute_data));
-	Z_OBJ(generator->execute_fake.This) = (zend_object *) generator;
-}
-/* }}} */
-
 static ZEND_COLD zend_function *zend_generator_get_constructor(zend_object *object) /* {{{ */
 {
 	zend_throw_error(NULL, "The \"Generator\" class is reserved for internal use and cannot be manually instantiated");
@@ -276,7 +389,7 @@ static ZEND_COLD zend_function *zend_generator_get_constructor(zend_object *obje
 
 ZEND_API zend_execute_data *zend_generator_check_placeholder_frame(zend_execute_data *ptr)
 {
-	if (!ptr->func && Z_OBJ(ptr->This)) {
+	if (!ptr->func && Z_TYPE(ptr->This) == IS_OBJECT) {
 		if (Z_OBJCE(ptr->This) == zend_ce_generator) {
 			zend_generator *generator = (zend_generator *) Z_OBJ(ptr->This);
 			zend_generator *root = (generator->node.children < 1 ? generator : generator->node.ptr.leaf)->node.ptr.root;
@@ -297,6 +410,8 @@ ZEND_API zend_execute_data *zend_generator_check_placeholder_frame(zend_execute_
 
 static void zend_generator_throw_exception(zend_generator *generator, zval *exception)
 {
+	zend_execute_data *original_execute_data = EG(current_execute_data);
+
 	/* if we don't stop an array/iterator yield from, the exception will only reach the generator after the values were all iterated over */
 	if (UNEXPECTED(Z_TYPE(generator->values) != IS_UNDEF)) {
 		zval_ptr_dtor(&generator->values);
@@ -305,7 +420,6 @@ static void zend_generator_throw_exception(zend_generator *generator, zval *exce
 
 	/* Throw the exception in the context of the generator. Decrementing the opline
 	 * to pretend the exception happened during the YIELD opcode. */
-	zend_execute_data *original_execute_data = EG(current_execute_data);
 	EG(current_execute_data) = generator->execute_data;
 	generator->execute_data->opline--;
 	if (exception) {
@@ -676,16 +790,9 @@ try_again:
 	{
 		/* Backup executor globals */
 		zend_execute_data *original_execute_data = EG(current_execute_data);
-		zend_class_entry *original_scope = EG(scope);
-		zend_vm_stack original_stack = EG(vm_stack);
-		original_stack->top = EG(vm_stack_top);
 
 		/* Set executor globals */
 		EG(current_execute_data) = generator->execute_data;
-		EG(scope) = generator->execute_data->func->common.scope;
-		EG(vm_stack_top) = generator->stack->top;
-		EG(vm_stack_end) = generator->stack->end;
-		EG(vm_stack) = generator->stack;
 
 		/* We want the backtrace to look as if the generator function was
 		 * called from whatever method we are current running (e.g. next()).
@@ -699,23 +806,25 @@ try_again:
 			orig_generator->execute_fake.prev_execute_data = original_execute_data;
 		}
 
+		if (UNEXPECTED(generator->frozen_call_stack)) {
+			/* Restore frozen call-stack */
+			zend_restore_call_stack(generator);
+		}
+
 		/* Resume execution */
 		generator->flags |= ZEND_GENERATOR_CURRENTLY_RUNNING;
 		zend_execute_ex(generator->execute_data);
 		generator->flags &= ~ZEND_GENERATOR_CURRENTLY_RUNNING;
 
-		/* Unlink generator call_frame from the caller and backup vm_stack_top */
-		if (EXPECTED(generator->execute_data)) {
-			generator->stack = EG(vm_stack);
-			generator->stack->top = EG(vm_stack_top);
+		generator->frozen_call_stack = NULL;
+		if (EXPECTED(generator->execute_data) &&
+		    UNEXPECTED(generator->execute_data->call)) {
+			/* Frize call-stack */
+			generator->frozen_call_stack = zend_freeze_call_stack(generator->execute_data);
 		}
 
 		/* Restore executor globals */
 		EG(current_execute_data) = original_execute_data;
-		EG(scope) = original_scope;
-		EG(vm_stack_top) = original_stack->top;
-		EG(vm_stack_end) = original_stack->end;
-		EG(vm_stack) = original_stack;
 
 		/* If an exception was thrown in the generator we have to internally
 		 * rethrow it in the parent scope.
@@ -741,7 +850,7 @@ try_again:
 }
 /* }}} */
 
-static void inline zend_generator_ensure_initialized(zend_generator *generator) /* {{{ */
+static inline void zend_generator_ensure_initialized(zend_generator *generator) /* {{{ */
 {
 	if (UNEXPECTED(Z_TYPE(generator->value) == IS_UNDEF) && EXPECTED(generator->execute_data) && EXPECTED(generator->node.parent == NULL)) {
 		generator->flags |= ZEND_GENERATOR_DO_INIT;
@@ -752,7 +861,7 @@ static void inline zend_generator_ensure_initialized(zend_generator *generator)
 }
 /* }}} */
 
-static void inline zend_generator_rewind(zend_generator *generator) /* {{{ */
+static inline void zend_generator_rewind(zend_generator *generator) /* {{{ */
 {
 	zend_generator_ensure_initialized(generator);
 
@@ -1075,7 +1184,8 @@ static zend_object_iterator_funcs zend_generator_iterator_functions = {
 	zend_generator_iterator_get_data,
 	zend_generator_iterator_get_key,
 	zend_generator_iterator_move_forward,
-	zend_generator_iterator_rewind
+	zend_generator_iterator_rewind,
+	NULL
 };
 
 zend_object_iterator *zend_generator_get_iterator(zend_class_entry *ce, zval *object, int by_ref) /* {{{ */