+ -- The calling conventions first assign arguments to registers,
+ -- then switch to the stack when we first run out of registers
+ -- (even if there are still available registers for args of a
+ -- different type).
+ -- When returning an unboxed tuple, we also separate the stack
+ -- arguments by pointerhood.
+ (reg_assts, stk_args) = assign_regs [] reps regs
+ stk_args' = case conv of NativeReturn -> part
+ PrimOpReturn -> part
+ _ -> stk_args
+ where part = uncurry (++)
+ (L.partition (not . isGcPtrType . arg_ty) stk_args)
+ stk_assts = assign_stk 0 [] (reverse stk_args')
+ assignments = reg_assts ++ stk_assts
+
+ assign_regs assts [] _ = (assts, [])
+ assign_regs assts (r:rs) regs = if isFloatType ty then float else int
+ where float = case (w, regs) of
+ (W32, (vs, f:fs, ds, ls)) -> k (RegisterParam f, (vs, fs, ds, ls))
+ (W64, (vs, fs, d:ds, ls)) -> k (RegisterParam d, (vs, fs, ds, ls))
+ (W80, _) -> panic "F80 unsupported register type"
+ _ -> (assts, (r:rs))
+ int = case (w, regs) of
+ (W128, _) -> panic "W128 unsupported register type"
+ (_, (v:vs, fs, ds, ls)) | widthInBits w <= widthInBits wordWidth
+ -> k (RegisterParam (v gcp), (vs, fs, ds, ls))
+ (_, (vs, fs, ds, l:ls)) | widthInBits w > widthInBits wordWidth
+ -> k (RegisterParam l, (vs, fs, ds, ls))
+ _ -> (assts, (r:rs))
+ k (asst, regs') = assign_regs ((r, asst) : assts) rs regs'
+ ty = arg_ty r
+ w = typeWidth ty
+ gcp | isGcPtrType ty = VGcPtr
+ | otherwise = VNonGcPtr
+
+ assign_stk offset assts [] = assts
+ assign_stk offset assts (r:rs) = assign_stk off' ((r, StackParam off') : assts) rs
+ where w = typeWidth (arg_ty r)
+ size = (((widthInBytes w - 1) `div` wORD_SIZE) + 1) * wORD_SIZE
+ off' = offset + size
+
+
+ -- DEAD CODE:
+ (old_sizes, old_assignments) = unzip $ assignArguments' reps (sum old_sizes) regs
+ old_assts' = map cvt old_assignments
+