ByVal, ///< Pass structure by value
InAlloca, ///< Pass structure in an alloca
Cold, ///< Marks function as being in a cold path.
+ Convergent, ///< Can only be moved to control-equivalent blocks
InlineHint, ///< Source said inlining was desirable
InReg, ///< Force argument to be passed in register
JumpTable, ///< Build jump-instruction tables and replace refs.