ocaml/asmcomp/alpha/proc.ml

210 lines
6.7 KiB
OCaml

(***********************************************************************)
(* *)
(* Objective Caml *)
(* *)
(* Xavier Leroy, projet Cristal, INRIA Rocquencourt *)
(* *)
(* Copyright 1996 Institut National de Recherche en Informatique et *)
(* Automatique. Distributed only by permission. *)
(* *)
(***********************************************************************)
(* $Id$ *)
(* Description of the Alpha processor *)
open Misc
open Cmm
open Reg
open Arch
open Mach
(* Instruction selection *)
let word_addressed = true
(* Registers available for register allocation *)
(* Register map:
$0 - $7 0 - 7 function results
$8 - $12 8 - 12 general purpose ($9 - $15 are preserved by C)
$13 allocation pointer
$14 allocation limit
$15 trap pointer
$16 - $22 13 - 19 function arguments
$23 - $25 temporaries (for the code gen and for the asm)
$26 - $30 stack ptr, global ptr, etc
$31 always zero
$f0 - $f7 100 - 107 function results
$f8 - $f15 108 - 115 general purpose ($f2 - $f9 preserved by C)
$f16 - $f23 116 - 123 function arguments
$f24 - $f29 124 - 129 general purpose
$f30 temporary
$f31 always zero *)
let int_reg_name = [|
(* 0-7 *) "$0"; "$1"; "$2"; "$3"; "$4"; "$5"; "$6"; "$7";
(* 8-12 *) "$8"; "$9"; "$10"; "$11"; "$12";
(* 13-19 *) "$16"; "$17"; "$18"; "$19"; "$20"; "$21"; "$22"
|]
let float_reg_name = [|
(* 100-107 *) "$f0"; "$f1"; "$f2"; "$f3"; "$f4"; "$f5"; "$f6"; "$f7";
(* 108-115 *) "$f8"; "$f9"; "$f10"; "$f11"; "$f12"; "$f13"; "$f14"; "$f15";
(* 116-123 *) "$f16"; "$f17"; "$f18"; "$f19"; "$f20"; "$f21"; "$f22"; "$f23";
(* 124-129 *) "$f24"; "$f25"; "$f26"; "$f27"; "$f28"; "$f29"
|]
let num_register_classes = 2
let register_class r =
match r.typ with
Int -> 0
| Addr -> 0
| Float -> 1
let num_available_registers = [| 20; 30 |]
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 20 Reg.dummy in
for i = 0 to 19 do v.(i) <- Reg.at_location Int (Reg i) done;
v
let hard_float_reg =
let v = Array.create 30 Reg.dummy in
for i = 0 to 29 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, Misc.align !ofs 16) (* Keep stack 16-aligned *)
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 13 18 116 123 outgoing arg
let loc_parameters arg =
let (loc, ofs) = calling_conventions 13 18 116 123 incoming arg in loc
let loc_results res =
let (loc, ofs) = calling_conventions 0 7 100 107 not_supported res in loc
(* On the Alpha, C functions have calling conventions similar to those
for Caml functions, except that integer and floating-point registers
for arguments are allocated "in sequence". E.g. a function
taking a float f1 and two ints i2 and i3 will put f1 in the
first float reg, i2 in the second int reg and i3 in the third int reg. *)
let ext_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; incr float
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 int; incr float
end else begin
loc.(i) <- stack_slot (make_stack !ofs) Float;
ofs := !ofs + size_float
end
done;
(loc, Misc.align !ofs 16) (* Keep stack 16-aligned *)
let loc_external_arguments arg =
ext_calling_conventions 13 18 116 121 outgoing arg
let loc_external_results res =
let (loc, ofs) = ext_calling_conventions 0 0 100 100 not_supported res in loc
let extcall_use_push = false
let loc_exn_bucket = phys_reg 0 (* $0 *)
(* Registers destroyed by operations *)
let destroyed_at_c_call = (* $9 - $12, $f2 - $f9 preserved *)
Array.of_list(List.map phys_reg
[0;1;2;3;4;5;6;7;8;13;14;15;16;17;18;19;
100;101;110;111;112;113;114;115;116;117;118;119;120;121;122;123;124;
125;126;127;128;129])
let destroyed_at_oper = function
Iop(Icall_ind | Icall_imm _ | Iextcall(_, true)) -> all_phys_regs
| Iop(Iextcall(_, false)) -> destroyed_at_c_call
| _ -> [||]
let destroyed_at_raise = all_phys_regs
(* Maximal register pressure *)
let safe_register_pressure = function
Iextcall(_, _) -> 4
| _ -> 19
let max_register_pressure = function
Iextcall(_, _) -> [| 4; 8 |]
| _ -> [| 19; 29 |]
(* Layout of the stack *)
let num_stack_slots = [| 0; 0 |]
let contains_calls = ref false
(* Calling the assembler *)
let assemble_file infile outfile =
Ccomp.command ("as -O2 -nocpp -o " ^ outfile ^ " " ^ infile)