#13442: Add a coercion/cast operator to CMM -------------------------------------+------------------------------------- Reporter: erikd | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: 8.4.1 Component: Compiler | Version: 8.0.1 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by rwbarton): Take any old function that calculates with `Double` like {{{#!hs f :: Double -> Double f x = x + 1 }}} and compile it with `-O -ddump-cmm`, and it will do things like {{{ cOz: _sOd::F64 = %MO_F_Add_W64(F64[R1 + 7], 1.0 :: W64); I64[Hp - 8] = GHC.Types.D#_con_info; F64[Hp] = _sOd::F64; R1 = Hp - 7; Sp = Sp + 8; call (P64[Sp])(R1) args: 8, res: 0, upd: 8; }}} `F64[A]` is the way to denote the 64-bit floating point quantity at address `A`. So internally Cmm has a representation of exactly the construct you need already. I'm just not sure whether it is possible to write that construct in a `.cmm` file. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13442#comment:7 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler