ocaml/asmcomp/arm/proc.ml

150 lines
4.4 KiB
OCaml

(***********************************************************************)
(* *)
(* Objective Caml *)
(* *)
(* Xavier Leroy, projet Cristal, INRIA Rocquencourt *)
(* *)
(* Copyright 1998 Institut National de Recherche en Informatique et *)
(* en Automatique. All rights reserved. This file is distributed *)
(* under the terms of the Q Public License version 1.0. *)
(* *)
(***********************************************************************)
(* $Id$ *)
(* Description of the ARM processor *)
open Misc
open Cmm
open Reg
open Arch
open Mach
(* Instruction selection *)
let word_addressed = false
(* Registers available for register allocation *)
(* Register map:
r0 - r3 general purpose (not preserved by C)
r4 - r7 general purpose (preserved)
r8 allocation pointer (preserved)
r9 platform register, usually reserved
r10 allocation limit (preserved)
r11 trap pointer (preserved)
r12 general purpose (not preserved by C)
r13 stack pointer
r14 return address
r15 program counter
*)
let int_reg_name = [|
"r0"; "r1"; "r2"; "r3"; "r4"; "r5"; "r6"; "r7"; "r12"
|]
let num_register_classes = 1
let register_class r = assert (r.typ <> Float); 0
let num_available_registers = [| 9 |]
let first_available_register = [| 0 |]
let register_name r = int_reg_name.(r)
let rotate_registers = true
(* Representation of hard registers by pseudo-registers *)
let hard_int_reg =
let v = Array.create 9 Reg.dummy in
for i = 0 to 8 do v.(i) <- Reg.at_location Int (Reg i) done;
v
let all_phys_regs = hard_int_reg
let phys_reg n = all_phys_regs.(n)
let stack_slot slot ty =
assert (ty <> Float);
Reg.at_location ty (Stack slot)
(* Calling conventions *)
(* XXX float types have already been expanded into pairs of integers.
So we cannot align these floats. See if that causes a problem. *)
let calling_conventions first_int last_int make_stack arg =
let loc = Array.create (Array.length arg) Reg.dummy in
let int = ref first_int in
let ofs = ref 0 in
for i = 0 to Array.length arg - 1 do
match arg.(i).typ with
Int | Addr as ty ->
if !int <= last_int then begin
loc.(i) <- phys_reg !int;
incr int
end else begin
loc.(i) <- stack_slot (make_stack !ofs) ty;
ofs := !ofs + size_int
end
| Float ->
assert false
done;
(loc, Misc.align !ofs 8)
let incoming ofs = Incoming ofs
let outgoing ofs = Outgoing ofs
let not_supported ofs = fatal_error "Proc.loc_results: cannot call"
let loc_arguments arg =
calling_conventions 0 7 outgoing arg
let loc_parameters arg =
let (loc, ofs) = calling_conventions 0 7 incoming arg in loc
let loc_results res =
let (loc, ofs) = calling_conventions 0 7 not_supported res in loc
let loc_external_arguments arg =
calling_conventions 0 3 outgoing arg
let loc_external_results res =
let (loc, ofs) = calling_conventions 0 1 not_supported res in loc
let loc_exn_bucket = phys_reg 0
(* Registers destroyed by operations *)
let destroyed_at_c_call = (* r4-r7 preserved *)
Array.of_list(List.map phys_reg [0;1;2;3;8])
let destroyed_at_oper = function
Iop(Icall_ind | Icall_imm _ | Iextcall(_, true)) -> all_phys_regs
| Iop(Iextcall(_, false)) -> destroyed_at_c_call
| Iop(Ialloc(_)) -> [|phys_reg 8|] (* r12 destroyed *)
| _ -> [||]
let destroyed_at_raise = all_phys_regs
(* Maximal register pressure *)
let safe_register_pressure = function
Iextcall(_, _) -> 4
| _ -> 9
let max_register_pressure = function
Iextcall(_, _) -> [| 4 |]
| _ -> [| 9 |]
(* Layout of the stack *)
let num_stack_slots = [| 0 |]
let contains_calls = ref false
(* Calling the assembler *)
let assemble_file infile outfile =
Ccomp.command (Config.asm ^ " -o " ^
Filename.quote outfile ^ " " ^ Filename.quote infile)
open Clflags;;
open Config;;