materialsystem: threaded optimizations, fix mat_queue_mode on some android devices

public/tier1/memhelpers.h

@@ -11,21 +11,15 @@ namespace memutils
 	template<typename T>
 	inline void copy( T *dest, const T *src, size_t n )
 	{
-		do
-		{
-			--n;
-			*(dest+n) = *(src+n);
-	        } while( n );
+		for(; n; n--)
+			*(dest++) = *(src++);
 	}
 
 	template<typename T>
-	inline void set( T *dest, T value, size_t n )
+	inline void set( T *dest, const T& value, size_t n )
 	{
-		do
-		{
-			--n;
-			*(dest+n) = value;
-		} while( n );
+		for(; n; n--)
+			*(dest++) = value;
 	}
 }