SQL server has 2 Memory Manager. Buffer Pool and Memory manager. Buffer Pool manage the single page , the primary consumer for the single pages are Data Buffer and procedure cache. There are other components not data buffer also use single page, it is call stolen page. When we configure SQL server MAX Memory, we actually only setup the the Max Size of the Buffer Pool ( Single page) only. When SQL Server needs multi pages ( page more than 8K), it switch to new implement memory manger. components outside of single pages are CLR, MPA, DWA and TS.
SQL Server 2012
Only one memory manager that mange all pages, including Buffer Pool. CLR does not directly manage by memory manager but track through the VAS allocator. components outside of memory manager are DWA and TS.

