-assignArgumentsPos conv isCall arg_ty reps = map cvt assignments
- where
- regs = case conv of Native -> getRegs isCall
- GC -> getRegs False
- PrimOp -> if isCall then noStack else getRegs isCall
- Slow -> noRegs
- _ -> getRegs isCall
- -- _ -> panic "unrecognized calling convention"
- (sizes, assignments) = unzip $ assignArguments' reps (sum sizes) regs
- assignArguments' [] _ _ = []
- assignArguments' (r:rs) offset avails =
- (size, (r,assignment)):assignArguments' rs new_offset remaining
- where
- (assignment, new_offset, size, remaining) =
- assign_reg assign_slot_pos (arg_ty r) offset avails
- cvt (l, RegisterParam r) = (l, RegisterParam r)
- cvt (l, StackParam off) = (l, StackParam $ off * wORD_SIZE)
-
+assignArgumentsPos conv arg_ty reps = assignments
+ where -- The calling conventions (CgCallConv.hs) are complicated, to say the least
+ regs = case (reps, conv) of
+ (_, NativeNodeCall) -> getRegsWithNode
+ (_, NativeDirectCall) -> getRegsWithoutNode
+ ([_], NativeReturn) -> allRegs
+ (_, NativeReturn) -> getRegsWithNode
+ -- GC calling convention *must* put values in registers
+ (_, GC) -> allRegs
+ (_, PrimOpCall) -> allRegs
+ ([_], PrimOpReturn) -> allRegs
+ (_, PrimOpReturn) -> getRegsWithNode
+ (_, Slow) -> noRegs
+ _ -> pprPanic "Unknown calling convention" (ppr conv)
+ -- 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
+ GC | length stk_args /= 0 -> panic "Failed to allocate registers for GC call"
+ _ -> 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 _ 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
+
+