[bitc-dev] BitC "idiot of the day" award

[Jonathan S. Shapiro]

I am awarding today's "idiot of the day" award to myself, for failing
to recognize that no new core types are required for C at all. What we
need is a target-specific module (we already have some of those) that
does something like:

;; On 32-bit platforms:
(defstruct c_short :val  val: int16)
(defstruct c_int     :val   val:int32)
(defstruct c_long  :val  val:int32)

;; On LP64 platforms:
(defstruct c_short :val  val: int16)
(defstruct c_int     :val   val:int32)
(defstruct c_long  :val  val:int64)

;; On ILP64 platforms:
(defstruct c_short :val  val: int16)
(defstruct c_int     :val   val:int64)
(defstruct c_long  :val  val:int64)


(definstance (Arith c_short)
   + = (lambda (x y) (c_short (+ x.val y.val)))
   - = (lambda (x y) (c_short (+ x.val y.val)))
  ...)

This relies on the calling convention requirement that structs whose
size is the same as a scalar are passed in registers. We can, if
necessary, introduce a DECLARE form for this.

The remaining issue is pretty printing, which is something we need to
look at more generally.

shap