ocaml/asmcomp/arm/proc.ml

195 lines
5.6 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 - r7 general purpose (r4 - r7 preserved by C)
r8 allocation pointer (preserved by C)
r9 allocation limit (preserved by C)
r10 general purpose
r11 trap pointer (preserved by C)
r12 general purpose
r13 stack pointer
r14 return address
r15 program counter
f0 - f6 general purpose (f4 - f6 preserved by C)
f7 temporary
*)
let int_reg_name = [|
"r0"; "r1"; "r2"; "r3"; "r4"; "r5"; "r6"; "r7"; "r10"; "r12"
|]
let float_reg_name = [|
"f0"; "f1"; "f2"; "f3"; "f4"; "f5"; "f6"
|]
let num_register_classes = 2
let register_class r =
match r.typ with
Int -> 0
| Addr -> 0
| Float -> 1
let num_available_registers = [| 10; 7 |]
let first_available_register = [| 0; 100 |]
let register_name r =
if r < 100 then int_reg_name.(r) else float_reg_name.(r - 100)
let rotate_registers = true
(* Representation of hard registers by pseudo-registers *)
let hard_int_reg =
let v = Array.create 10 Reg.dummy in
for i = 0 to 9 do v.(i) <- Reg.at_location Int (Reg i) done;
v
let hard_float_reg =
let v = Array.create 7 Reg.dummy in
for i = 0 to 6 do v.(i) <- Reg.at_location Float (Reg(100 + i)) done;
v
let all_phys_regs =
Array.append hard_int_reg hard_float_reg
let phys_reg n =
if n < 100 then hard_int_reg.(n) else hard_float_reg.(n - 100)
let stack_slot slot ty =
Reg.at_location ty (Stack slot)
(* Calling conventions *)
let calling_conventions first_int last_int first_float last_float
make_stack arg =
let loc = Array.create (Array.length arg) Reg.dummy in
let int = ref first_int in
let float = ref first_float 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 ->
if !float <= last_float then begin
loc.(i) <- phys_reg !float;
incr float
end else begin
loc.(i) <- stack_slot (make_stack !ofs) Float;
ofs := !ofs + size_float
end
done;
(loc, !ofs)
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 7 100 103 outgoing arg
let loc_parameters arg =
let (loc, ofs) = calling_conventions 0 7 100 103 incoming arg in loc
let loc_results res =
let (loc, ofs) = calling_conventions 0 7 100 103 not_supported res in loc
(* Calling conventions for C are as for Caml, except that float arguments
are passed in pairs of integer registers. *)
let loc_external_arguments arg =
let loc = Array.create (Array.length arg) Reg.dummy in
let reg = ref 0 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 !reg <= 3 then begin
loc.(i) <- phys_reg !reg;
incr reg
end else begin
loc.(i) <- stack_slot (outgoing !ofs) ty;
ofs := !ofs + size_int
end
| Float ->
if !reg <= 2 then begin
loc.(i) <- phys_reg !reg;
reg := !reg + 2
end else begin
loc.(i) <- stack_slot (outgoing !ofs) Float;
ofs := !ofs + size_float
end
done;
(loc, !ofs)
let loc_external_results res =
let (loc, ofs) = calling_conventions 0 0 100 100 not_supported res in loc
let loc_exn_bucket = phys_reg 0
(* Registers destroyed by operations *)
let destroyed_at_c_call = (* r4-r9, f4-f6 preserved *)
Array.of_list(List.map phys_reg [0;1;2;3;8;9; 100;101;102;103])
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|] (* r10 destroyed *)
| _ -> [||]
let destroyed_at_raise = all_phys_regs
(* Maximal register pressure *)
let safe_register_pressure = function
Iextcall(_, _) -> 4
| _ -> 7
let max_register_pressure = function
Iextcall(_, _) -> [| 4; 4 |]
| _ -> [| 10; 7 |]
(* Layout of the stack *)
let num_stack_slots = [| 0; 0 |]
let contains_calls = ref false
(* Calling the assembler *)
let assemble_file infile outfile =
Sys.command ("as -o " ^ Filename.quote outfile ^ " " ^ Filename.quote infile)