The Note 4 does not have the same processor as the S6. The S6 processor is Samsung's latest based on an all new fabrication process. The note 4 does come in two variants however; one snapdragon and the other with the Exynos. The snapdragon's GPU capabilities are better but the Exynos' CPU capabilities are better. I don't know how much this translates to actual field testing. I would lean toward the Exynos, but the reason Samsung didn't use the Exynos in these last couple of release cycles because they had issues with producing the chip.
The Exynos has typically outperformed the snapdragon and other processors Samsung has used going all the way back to the S2.