Make Stack::Push() force inline in normal path

1 files changed, 19 insertions, 12 deletions

diff --git a/include/rapidjson/internal/stack.h b/include/rapidjson/internal/stack.h
index ff5ff82a..85484655 100644
--- a/include/rapidjson/internal/stack.h
+++ b/include/rapidjson/internal/stack.h
@@ -28,20 +28,14 @@ public:
 

 	void Clear() { /*stack_top_ = 0;*/ stack_top_ = stack_; }

 

+	// Optimization note: try to minimize the size of this function for force inline.

+	// Expansion is run very infrequently, so it is moved to another (probably non-inline) function.

 	template<typename T>

-	T* Push(size_t count = 1) {

+	RAPIDJSON_FORCEINLINE T* Push(size_t count = 1) {

 		 // Expand the stack if needed

-		if (stack_top_ + sizeof(T) * count >= stack_end_) {

-			size_t new_capacity = stack_capacity_ * 2;

-			size_t size = GetSize();

-			size_t new_size = GetSize() + sizeof(T) * count;

-			if (new_capacity < new_size)

-				new_capacity = new_size;

-			stack_ = (char*)allocator_->Realloc(stack_, stack_capacity_, new_capacity);

-			stack_capacity_ = new_capacity;

-			stack_top_ = stack_ + size;

-			stack_end_ = stack_ + stack_capacity_;

-		}

+		if (stack_top_ + sizeof(T) * count >= stack_end_)

+			Expand<T>(count);

+

 		T* ret = reinterpret_cast<T*>(stack_top_);

 		stack_top_ += sizeof(T) * count;

 		return ret;

@@ -69,6 +63,19 @@ public:
 	size_t GetCapacity() const { return stack_capacity_; }

 

 private:

+	template<typename T>

+	void Expand(size_t count) {

+		size_t new_capacity = stack_capacity_ * 2;

+		size_t size = GetSize();

+		size_t new_size = GetSize() + sizeof(T) * count;

+		if (new_capacity < new_size)

+			new_capacity = new_size;

+		stack_ = (char*)allocator_->Realloc(stack_, stack_capacity_, new_capacity);

+		stack_capacity_ = new_capacity;

+		stack_top_ = stack_ + size;

+		stack_end_ = stack_ + stack_capacity_;

+	}

+

 	// Prohibit copy constructor & assignment operator.

 	Stack(const Stack&);

 	Stack& operator=(const Stack&);