+genCCall target dest_regs argsAndHints
+ = do
+ -- strip hints from the arg regs
+ let args :: [CmmExpr]
+ args = map hintlessCmm argsAndHints
+
+
+ -- work out the arguments, and assign them to integer regs
+ argcode_and_vregs <- mapM arg_to_int_vregs args
+ let (argcodes, vregss) = unzip argcode_and_vregs
+ let vregs = concat vregss
+
+ let n_argRegs = length allArgRegs
+ let n_argRegs_used = min (length vregs) n_argRegs
+
+
+ -- deal with static vs dynamic call targets
+ callinsns <- case target of
+ CmmCallee (CmmLit (CmmLabel lbl)) conv ->
+ return (unitOL (CALL (Left (litToImm (CmmLabel lbl))) n_argRegs_used False))
+
+ CmmCallee expr conv
+ -> do (dyn_c, [dyn_r]) <- arg_to_int_vregs expr
+ return (dyn_c `snocOL` CALL (Right dyn_r) n_argRegs_used False)
+
+ CmmPrim mop
+ -> do res <- outOfLineFloatOp mop
+ lblOrMopExpr <- case res of
+ Left lbl -> do
+ return (unitOL (CALL (Left (litToImm (CmmLabel lbl))) n_argRegs_used False))
+
+ Right mopExpr -> do
+ (dyn_c, [dyn_r]) <- arg_to_int_vregs mopExpr
+ return (dyn_c `snocOL` CALL (Right dyn_r) n_argRegs_used False)
+
+ return lblOrMopExpr
+
+ let argcode = concatOL argcodes
+
+ let (move_sp_down, move_sp_up)
+ = let diff = length vregs - n_argRegs
+ nn = if odd diff then diff + 1 else diff -- keep 8-byte alignment
+ in if nn <= 0
+ then (nilOL, nilOL)
+ else (unitOL (moveSp (-1*nn)), unitOL (moveSp (1*nn)))
+
+ let transfer_code
+ = toOL (move_final vregs allArgRegs eXTRA_STK_ARGS_HERE)
+
+ return
+ $ argcode `appOL`
+ move_sp_down `appOL`
+ transfer_code `appOL`
+ callinsns `appOL`
+ unitOL NOP `appOL`
+ move_sp_up `appOL`
+ assign_code dest_regs
+
+
+-- | Generate code to calculate an argument, and move it into one
+-- or two integer vregs.
+arg_to_int_vregs :: CmmExpr -> NatM (OrdList Instr, [Reg])
+arg_to_int_vregs arg
+
+ -- If the expr produces a 64 bit int, then we can just use iselExpr64
+ | isWord64 (cmmExprType arg)
+ = do (ChildCode64 code r_lo) <- iselExpr64 arg
+ let r_hi = getHiVRegFromLo r_lo
+ return (code, [r_hi, r_lo])
+
+ | otherwise
+ = do (src, code) <- getSomeReg arg
+ tmp <- getNewRegNat (cmmTypeSize $ cmmExprType arg)
+ let pk = cmmExprType arg
+
+ case cmmTypeSize pk of
+
+ -- Load a 64 bit float return value into two integer regs.
+ FF64 -> do
+ v1 <- getNewRegNat II32
+ v2 <- getNewRegNat II32
+
+ let Just f0_high = fPair f0