ocaml/asmcomp/selection.ml

689 lines
23 KiB
OCaml

(***********************************************************************)
(* *)
(* Caml Special Light *)
(* *)
(* Xavier Leroy, projet Cristal, INRIA Rocquencourt *)
(* *)
(* Copyright 1995 Institut National de Recherche en Informatique et *)
(* Automatique. Distributed only by permission. *)
(* *)
(***********************************************************************)
(* $Id$ *)
(* Selection of pseudo-instructions, assignment of pseudo-registers,
sequentialization. *)
open Misc
open Cmm
open Reg
open Mach
(* Infer the type of the result of an operation *)
let oper_result_type = function
Capply ty -> ty
| Cextcall(s, ty, alloc) -> ty
| Cload ty -> ty
| Cloadchunk c -> typ_int
| Calloc -> typ_addr
| Cstore -> typ_void
| Cstorechunk c -> typ_void
| Caddi | Csubi | Cmuli | Cdivi | Cmodi
| Cand | Cor | Cxor | Clsl | Clsr | Casr
| Ccmpi _ | Ccmpa _ | Ccmpf _ -> typ_int
| Cadda | Csuba -> typ_addr
| Cnegf | Cabsf | Caddf | Csubf | Cmulf | Cdivf -> typ_float
| Cfloatofint -> typ_float
| Cintoffloat -> typ_int
| Craise -> typ_void
| Ccheckbound -> typ_void
| _ -> fatal_error "Selection.oper_result_type"
(* Infer the size in bytes of the result of a simple expression *)
let rec size_expr env = function
Cconst_int _ -> Arch.size_int
| Cconst_symbol _ | Cconst_pointer _ -> Arch.size_addr
| Cconst_float _ -> Arch.size_float
| Cvar v ->
let r =
try
Tbl.find v env
with Not_found ->
fatal_error("Selection.emit_expr: unbound var " ^ Ident.name v) in
size_machtype (Array.map (fun r -> r.typ) r)
| Ctuple el ->
List.fold_right (fun e sz -> size_expr env e + sz) el 0
| Cop(op, args) ->
size_machtype(oper_result_type op)
| _ ->
fatal_error "Selection.size_expr"
(* Says if an operation is "cheap". A "cheap" operation is an operation
without side-effects and whose execution can be delayed until its value
is really needed. In the case of e.g. an [alloc] instruction,
the non-cheap parts of arguments are computed in right-to-left order
first, then the block is allocated, then the cheap parts are evaluated
and stored. *)
let cheap_operation = function
(* The following may have side effects *)
Capply _ | Cextcall(_, _, _) | Calloc | Cstore | Cstorechunk _ |
Craise -> false
(* The remaining operations are cheap *)
| _ -> true
(* Default instruction selection for operators *)
let rec sel_operation op args =
match (op, args) with
(Capply ty, Cconst_symbol s :: rem) -> (Icall_imm s, rem)
| (Capply ty, _) -> (Icall_ind, args)
| (Cextcall(s, ty, alloc), _) -> (Iextcall(s, alloc), args)
| (Cload ty, [arg]) ->
let (addr, eloc) = Proc.select_addressing arg in
(Iload(Word, addr), [eloc])
| (Cloadchunk chunk, [arg]) ->
let (addr, eloc) = Proc.select_addressing arg in
(Iload(chunk, addr), [eloc])
| (Cstore, arg1 :: rem) ->
let (addr, eloc) = Proc.select_addressing arg1 in
(Istore(Word, addr), eloc :: rem)
| (Cstorechunk chunk, [arg1; arg2]) ->
let (addr, eloc) = Proc.select_addressing arg1 in
(Istore(chunk, addr), [arg2; eloc])
(* Inversion addr/datum in Istore *)
| (Calloc, _) -> (Ialloc 0, args)
| (Caddi, _) -> sel_arith_comm Iadd args
| (Csubi, _) -> sel_arith Isub args
| (Cmuli, [arg1; Cconst_int n]) ->
let l = Misc.log2 n in
if n = 1 lsl l
then (Iintop_imm(Ilsl, l), [arg1])
else sel_arith_comm Imul args
| (Cmuli, [Cconst_int n; arg1]) ->
let l = Misc.log2 n in
if n = 1 lsl l
then (Iintop_imm(Ilsl, l), [arg1])
else sel_arith_comm Imul args
| (Cmuli, _) -> sel_arith_comm Imul args
| (Cdivi, _) -> sel_arith Idiv args
| (Cmodi, _) -> sel_arith_comm Imod args
| (Cand, _) -> sel_arith_comm Iand args
| (Cor, _) -> sel_arith_comm Ior args
| (Cxor, _) -> sel_arith_comm Ixor args
| (Clsl, _) -> sel_shift Ilsl args
| (Clsr, _) -> sel_shift Ilsr args
| (Casr, _) -> sel_shift Iasr args
| (Ccmpi comp, _) -> sel_arith_comp (Isigned comp) args
| (Cadda, _) -> sel_arith_comm Iadd args
| (Csuba, _) -> sel_arith Isub args
| (Ccmpa comp, _) -> sel_arith_comp (Iunsigned comp) args
| (Cnegf, _) -> (Inegf, args)
| (Cabsf, _) -> (Iabsf, args)
| (Caddf, _) -> (Iaddf, args)
| (Csubf, _) -> (Isubf, args)
| (Cmulf, _) -> (Imulf, args)
| (Cdivf, _) -> (Idivf, args)
| (Cfloatofint, _) -> (Ifloatofint, args)
| (Cintoffloat, _) -> (Iintoffloat, args)
| (Ccheckbound, _) -> sel_arith Icheckbound args
| _ -> fatal_error "Selection.sel_oper"
and sel_arith_comm op = function
[arg; Cconst_int n] when Proc.is_immediate n ->
(Iintop_imm(op, n), [arg])
| [arg; Cconst_pointer n] when Proc.is_immediate n ->
(Iintop_imm(op, n), [arg])
| [Cconst_int n; arg] when Proc.is_immediate n ->
(Iintop_imm(op, n), [arg])
| [Cconst_pointer n; arg] when Proc.is_immediate n ->
(Iintop_imm(op, n), [arg])
| args ->
(Iintop op, args)
and sel_arith op = function
[arg; Cconst_int n] when Proc.is_immediate n ->
(Iintop_imm(op, n), [arg])
| [arg; Cconst_pointer n] when Proc.is_immediate n ->
(Iintop_imm(op, n), [arg])
| args ->
(Iintop op, args)
and sel_shift op = function
[arg; Cconst_int n] when n >= 0 & n < Arch.size_int * 8 ->
(Iintop_imm(op, n), [arg])
| args ->
(Iintop op, args)
and sel_arith_comp cmp = function
[arg; Cconst_int n] when Proc.is_immediate n ->
(Iintop_imm(Icomp cmp, n), [arg])
| [arg; Cconst_pointer n] when Proc.is_immediate n ->
(Iintop_imm(Icomp cmp, n), [arg])
| [Cconst_int n; arg] when Proc.is_immediate n ->
(Iintop_imm(Icomp(swap_intcomp cmp), n), [arg])
| [Cconst_pointer n; arg] when Proc.is_immediate n ->
(Iintop_imm(Icomp(swap_intcomp cmp), n), [arg])
| args ->
(Iintop(Icomp cmp), args)
and swap_intcomp = function
Isigned cmp -> Isigned(swap_comparison cmp)
| Iunsigned cmp -> Iunsigned(swap_comparison cmp)
(* Instruction selection for conditionals *)
let sel_condition = function
Cop(Ccmpi cmp, [arg1; Cconst_int n]) when Proc.is_immediate n ->
(Iinttest_imm(Isigned cmp, n), arg1)
| Cop(Ccmpi cmp, [Cconst_int n; arg2]) when Proc.is_immediate n ->
(Iinttest_imm(Isigned(swap_comparison cmp), n), arg2)
| Cop(Ccmpi cmp, args) ->
(Iinttest(Isigned cmp), Ctuple args)
| Cop(Ccmpa cmp, [arg1; Cconst_pointer n]) when Proc.is_immediate n ->
(Iinttest_imm(Iunsigned cmp, n), arg1)
| Cop(Ccmpa cmp, [Cconst_pointer n; arg2]) when Proc.is_immediate n ->
(Iinttest_imm(Iunsigned(swap_comparison cmp), n), arg2)
| Cop(Ccmpa cmp, args) ->
(Iinttest(Iunsigned cmp), Ctuple args)
| Cop(Ccmpf cmp, args) ->
(Ifloattest(cmp, false), Ctuple args)
| Cop(Cand, [arg; Cconst_int 1]) ->
(Ioddtest, arg)
| arg ->
(Itruetest, arg)
(* Naming of registers *)
let all_regs_anonymous rv =
try
for i = 0 to Array.length rv - 1 do
if String.length rv.(i).name > 0 then raise Exit
done;
true
with Exit ->
false
let name_regs id rv =
if Array.length rv = 1 then
rv.(0).name <- Ident.name id
else
for i = 0 to Array.length rv - 1 do
rv.(i).name <- Ident.name id ^ "#" ^ string_of_int i
done
(* Buffering of instruction sequences *)
type instruction_sequence = instruction ref
let new_sequence() = ref dummy_instr
let insert desc arg res seq =
seq := instr_cons desc arg res !seq
let extract_sequence seq =
let rec extract res i =
if i == dummy_instr
then res
else extract (instr_cons i.desc i.arg i.res res) i.next in
extract (end_instr()) !seq
(* Insert a sequence of moves from one pseudoreg set to another. *)
let insert_move src dst seq =
if src.stamp <> dst.stamp then
insert (Iop Imove) [|src|] [|dst|] seq
let insert_moves src dst seq =
for i = 0 to Array.length src - 1 do
insert_move src.(i) dst.(i) seq
done
(* Insert moves and stack offsets for function arguments and results *)
let insert_move_args arg loc stacksize seq =
if stacksize <> 0 then insert (Iop(Istackoffset stacksize)) [||] [||] seq;
insert_moves arg loc seq
let insert_move_results loc res stacksize seq =
if stacksize <> 0 then insert(Iop(Istackoffset(-stacksize))) [||] [||] seq;
insert_moves loc res seq
(* "Join" two instruction sequences, making sure they return their results
in the same registers. *)
let join r1 seq1 r2 seq2 =
let l1 = Array.length r1 and l2 = Array.length r2 in
if l1 = 0 then r2
else if l2 = 0 then r1
else begin
let r = Array.new l1 Reg.dummy in
for i = 0 to l1-1 do
if String.length r1.(i).name = 0 then begin
r.(i) <- r1.(i);
insert_move r2.(i) r1.(i) seq2
end else if String.length r2.(i).name = 0 then begin
r.(i) <- r2.(i);
insert_move r1.(i) r2.(i) seq1
end else begin
r.(i) <- Reg.new r1.(i).typ;
insert_move r1.(i) r.(i) seq1;
insert_move r2.(i) r.(i) seq2
end
done;
r
end
(* Same, for N branches *)
let join_array rs =
let some_res = ref [||] in
for i = 0 to Array.length rs - 1 do
let (r, s) = rs.(i) in
if Array.length r > 0 then some_res := r
done;
let size_res = Array.length !some_res in
if size_res = 0 then [||] else begin
let res = Array.new size_res Reg.dummy in
for i = 0 to size_res - 1 do
res.(i) <- Reg.new (!some_res).(i).typ
done;
for i = 0 to Array.length rs - 1 do
let (r, s) = rs.(i) in
if Array.length r > 0 then insert_moves r res s
done;
res
end
(* Add an Iop opcode.
Offer the processor description an opportunity to insert moves
before and after the operation, i.e. for two-address
instructions, or instructions using dedicated registers. *)
let insert_op op rs rd seq =
try
let (rsrc, rdst, move_res) = Proc.pseudoregs_for_operation op rs rd in
insert_moves rs rsrc seq;
insert (Iop op) rsrc rdst seq;
if move_res then begin
insert_moves rdst rd seq;
rd
end else
rdst
with Proc.Use_default ->
(* Assume no constraints on arg and res registers *)
insert (Iop op) rs rd seq;
rd
(* Add the instructions for the given expression
at the end of the given sequence *)
let rec emit_expr env exp seq =
match exp with
Cconst_int n ->
let r = Reg.newv typ_int in
insert_op (Iconst_int n) [||] r seq
| Cconst_float n ->
let r = Reg.newv typ_float in
insert_op (Iconst_float n) [||] r seq
| Cconst_symbol n ->
let r = Reg.newv typ_addr in
insert_op (Iconst_symbol n) [||] r seq
| Cconst_pointer n ->
let r = Reg.newv typ_addr in
insert_op (Iconst_int n) [||] r seq
| Cvar v ->
begin try
Tbl.find v env
with Not_found ->
fatal_error("Selection.emit_expr: unbound var " ^ Ident.name v)
end
| Clet(v, e1, e2) ->
emit_expr (emit_let env v e1 seq) e2 seq
| Cassign(v, e1) ->
let rv =
try
Tbl.find v env
with Not_found ->
fatal_error ("Selection.emit_expr: unbound var " ^ Ident.name v) in
let r1 = emit_expr env e1 seq in
insert_moves r1 rv seq;
[||]
| Ctuple exp_list ->
let (simple_list, ext_env) = emit_parts_list env exp_list seq in
emit_tuple ext_env simple_list seq
| Cop(Cproj(ofs, len), [Cop(Cload ty, [arg])]) ->
let byte_offset = size_machtype(Array.sub ty 0 ofs) in
emit_expr env
(Cop(Cload(Array.sub ty ofs len),
[Cop(Cadda, [arg; Cconst_int byte_offset])])) seq
| Cop(Cproj(ofs, len), [arg]) ->
let r = emit_expr env arg seq in
Array.sub r ofs len
| Cop(Craise, [arg]) ->
let r1 = emit_expr env arg seq in
let rd = [|Proc.loc_exn_bucket|] in
insert (Iop Imove) r1 rd seq;
insert Iraise rd [||] seq;
[||]
| Cop(Ccmpf comp, args) ->
emit_expr env (Cifthenelse(exp, Cconst_int 1, Cconst_int 0)) seq
| Cop(op, args) ->
let (simple_args, env) = emit_parts_list env args seq in
let ty = oper_result_type op in
let (new_op, new_args) =
try
Proc.select_oper op simple_args
with Proc.Use_default ->
sel_operation op simple_args in
begin match new_op with
Icall_ind ->
Proc.contains_calls := true;
let r1 = emit_tuple env new_args seq in
let rarg = Array.sub r1 1 (Array.length r1 - 1) in
let rd = Reg.newv ty in
let (loc_arg, stack_ofs) = Proc.loc_arguments rarg in
let loc_res = Proc.loc_results rd in
insert_move_args rarg loc_arg stack_ofs seq;
insert (Iop Icall_ind) (Array.append [|r1.(0)|] loc_arg) loc_res seq;
insert_move_results loc_res rd stack_ofs seq;
rd
| Icall_imm lbl ->
Proc.contains_calls := true;
let r1 = emit_tuple env new_args seq in
let rd = Reg.newv ty in
let (loc_arg, stack_ofs) = Proc.loc_arguments r1 in
let loc_res = Proc.loc_results rd in
insert_move_args r1 loc_arg stack_ofs seq;
insert (Iop(Icall_imm lbl)) loc_arg loc_res seq;
insert_move_results loc_res rd stack_ofs seq;
rd
| Iextcall(lbl, alloc) ->
Proc.contains_calls := true;
let r1 = emit_tuple env new_args seq in
let rd = Reg.newv ty in
let (loc_arg, stack_ofs) = Proc.loc_external_arguments r1 in
let loc_res = Proc.loc_external_results rd in
insert_move_args r1 loc_arg stack_ofs seq;
insert (Iop(Iextcall(lbl, alloc))) loc_arg loc_res seq;
insert_move_results loc_res rd stack_ofs seq;
rd
| Iload(Word, addr) ->
let r1 = emit_tuple env new_args seq in
let rd = Reg.newv ty in
insert_op (Iload(Word, addr)) r1 rd seq
| Istore(Word, addr) ->
begin match new_args with
[] -> fatal_error "Selection.Istore"
| arg_addr :: args_data ->
let ra = emit_expr env arg_addr seq in
emit_stores env args_data seq ra addr;
[||]
end
| Ialloc _ ->
Proc.contains_calls := true;
let rd = Reg.newv typ_addr in
let size = size_expr env (Ctuple new_args) in
insert (Iop(Ialloc size)) [||] rd seq;
emit_stores env new_args seq rd
(Arch.offset_addressing Arch.identity_addressing (-Arch.size_int));
rd
| op ->
let r1 = emit_tuple env new_args seq in
let rd = Reg.newv ty in
insert_op op r1 rd seq
end
| Csequence(e1, e2) ->
emit_expr env e1 seq;
emit_expr env e2 seq
| Cifthenelse(econd, eif, eelse) ->
let (cond, earg) = sel_condition econd in
let rarg = emit_expr env earg seq in
let (rif, sif) = emit_sequence env eif in
let (relse, selse) = emit_sequence env eelse in
let r = join rif sif relse selse in
insert (Iifthenelse(cond, extract_sequence sif, extract_sequence selse))
rarg [||] seq;
r
| Cswitch(esel, index, ecases) ->
let rsel = emit_expr env esel seq in
let rscases = Array.map (emit_sequence env) ecases in
let r = join_array rscases in
insert (Iswitch(index,
Array.map (fun (r, s) -> extract_sequence s) rscases))
rsel [||] seq;
r
| Cloop(ebody) ->
let (rarg, sbody) = emit_sequence env ebody in
insert (Iloop(extract_sequence sbody)) [||] [||] seq;
[||]
| Ccatch(e1, e2) ->
let (r1, s1) = emit_sequence env e1 in
let (r2, s2) = emit_sequence env e2 in
let r = join r1 s1 r2 s2 in
insert (Icatch(extract_sequence s1, extract_sequence s2)) [||] [||] seq;
r
| Cexit ->
insert Iexit [||] [||] seq;
[||]
| Ctrywith(e1, v, e2) ->
Proc.contains_calls := true;
let (r1, s1) = emit_sequence env e1 in
let rv = Reg.newv typ_addr in
let (r2, s2) = emit_sequence (Tbl.add v rv env) e2 in
let r = join r1 s1 r2 s2 in
insert
(Itrywith(extract_sequence s1,
instr_cons (Iop Imove) [|Proc.loc_exn_bucket|] rv
(extract_sequence s2)))
[||] [||] seq;
r
and emit_sequence env exp =
let seq = new_sequence() in
let r = emit_expr env exp seq in
(r, seq)
and emit_let env v e1 seq =
let r1 = emit_expr env e1 seq in
if all_regs_anonymous r1 then begin
name_regs v r1;
Tbl.add v r1 env
end else begin
let rv = Array.new (Array.length r1) Reg.dummy in
for i = 0 to Array.length r1 - 1 do rv.(i) <- Reg.new r1.(i).typ done;
name_regs v rv;
insert_moves r1 rv seq;
Tbl.add v rv env
end
and emit_parts env exp seq =
match exp with
Cconst_int _ | Cconst_float _ | Cconst_symbol _ | Cconst_pointer _ |
Cvar _ ->
(exp, env)
| Ctuple el ->
let (explist, env) = emit_parts_list env el seq in
(Ctuple explist, env)
| Clet(id, arg, body) ->
emit_parts (emit_let env id arg seq) body seq
| Cop(op, args) when cheap_operation op ->
let (new_args, new_env) = emit_parts_list env args seq in
(Cop(op, new_args), new_env)
| _ ->
let r = emit_expr env exp seq in
if Array.length r = 0 then
(Ctuple [], env)
else begin
let id = Ident.new "bind" in
if all_regs_anonymous r then
(Cvar id, Tbl.add id r env)
else begin
let rv = Array.new (Array.length r) Reg.dummy in
for i = 0 to Array.length r - 1 do
rv.(i) <- Reg.new r.(i).typ
done;
insert_moves r rv seq;
(Cvar id, Tbl.add id rv env)
end
end
and emit_parts_list env exp_list seq =
match exp_list with
[] -> ([], env)
| exp :: rem ->
(* This ensures right-to-left evaluation, consistent with the
bytecode compiler *)
let (new_rem, new_env) = emit_parts_list env rem seq in
let (new_exp, fin_env) = emit_parts new_env exp seq in
(new_exp :: new_rem, fin_env)
and emit_tuple env exp_list seq =
let rec emit_list = function
[] -> []
| exp :: rem ->
(* Again, force right-to-left evaluation *)
let loc_rem = emit_list rem in
let loc_exp = emit_expr env exp seq in
loc_exp :: loc_rem in
Array.concat(emit_list exp_list)
and emit_stores env data seq regs_addr addr =
let a = ref addr in
List.iter
(fun e ->
try
(* Offer the machine description an opportunity to optimize
the store, e.g. if constant -> memory or memory -> memory
moves are available *)
let (op, arg) = Proc.select_store !a e in
let r = emit_expr env arg seq in
insert (Iop op) (Array.append r regs_addr) [||] seq;
a := Arch.offset_addressing !a (size_expr env e)
with Proc.Use_default ->
let r = emit_expr env e seq in
for i = 0 to Array.length r - 1 do
insert (Iop(Istore(Word, !a)))
(Array.append [|r.(i)|] regs_addr) [||] seq;
a := Arch.offset_addressing !a (size_component r.(i).typ)
done)
data
(* Same, but in tail position *)
let emit_return env exp seq =
let r = emit_expr env exp seq in
let loc = Proc.loc_results r in
insert_moves r loc seq;
insert Ireturn loc [||] seq
let rec emit_tail env exp seq =
match exp with
Clet(v, e1, e2) ->
emit_tail (emit_let env v e1 seq) e2 seq
| Cop(Capply ty as op, args) ->
let (simple_args, env) = emit_parts_list env args seq in
let (new_op, new_args) = sel_operation op simple_args in
begin match new_op with
Icall_ind ->
let r1 = emit_tuple env new_args seq in
let rarg = Array.sub r1 1 (Array.length r1 - 1) in
let (loc_arg, stack_ofs) = Proc.loc_arguments rarg in
if stack_ofs = 0 then begin
insert_moves rarg loc_arg seq;
insert (Iop Itailcall_ind)
(Array.append [|r1.(0)|] loc_arg) [||] seq
end else begin
Proc.contains_calls := true;
let rd = Reg.newv ty in
let loc_res = Proc.loc_results rd in
insert_move_args rarg loc_arg stack_ofs seq;
insert (Iop Icall_ind)
(Array.append [|r1.(0)|] loc_arg) loc_res seq;
insert(Iop(Istackoffset(-stack_ofs))) [||] [||] seq;
insert Ireturn loc_res [||] seq
end
| Icall_imm lbl ->
let r1 = emit_tuple env new_args seq in
let (loc_arg, stack_ofs) = Proc.loc_arguments r1 in
if stack_ofs = 0 then begin
insert_moves r1 loc_arg seq;
insert (Iop(Itailcall_imm lbl)) loc_arg [||] seq
end else begin
Proc.contains_calls := true;
let rd = Reg.newv ty in
let loc_res = Proc.loc_results rd in
insert_move_args r1 loc_arg stack_ofs seq;
insert (Iop(Icall_imm lbl)) loc_arg loc_res seq;
insert(Iop(Istackoffset(-stack_ofs))) [||] [||] seq;
insert Ireturn loc_res [||] seq
end
| _ -> fatal_error "Selection.emit_tail"
end
| Cop(Craise, [e1]) ->
let r1 = emit_expr env e1 seq in
let rd = [|Proc.loc_exn_bucket|] in
insert (Iop Imove) r1 rd seq;
insert Iraise rd [||] seq
| Csequence(e1, e2) ->
emit_expr env e1 seq;
emit_tail env e2 seq
| Cifthenelse(econd, eif, eelse) ->
let (cond, earg) = sel_condition econd in
let rarg = emit_expr env earg seq in
insert (Iifthenelse(cond, emit_tail_sequence env eif,
emit_tail_sequence env eelse))
rarg [||] seq
| Cswitch(esel, index, ecases) ->
let rsel = emit_expr env esel seq in
insert (Iswitch(index, Array.map (emit_tail_sequence env) ecases))
rsel [||] seq
| Ccatch(e1, e2) ->
insert (Icatch(emit_tail_sequence env e1, emit_tail_sequence env e2))
[||] [||] seq
| Cexit ->
insert Iexit [||] [||] seq
| Ctrywith(e1, v, e2) ->
Proc.contains_calls := true;
let (r1, s1) = emit_sequence env e1 in
let rv = Reg.newv typ_addr in
let s2 = emit_tail_sequence (Tbl.add v rv env) e2 in
let loc = Proc.loc_results r1 in
insert
(Itrywith(extract_sequence s1,
instr_cons (Iop Imove) [|Proc.loc_exn_bucket|] rv s2))
[||] [||] seq;
insert_moves r1 loc seq;
insert Ireturn loc [||] seq
| _ ->
emit_return env exp seq
and emit_tail_sequence env exp =
let seq = new_sequence() in
emit_tail env exp seq;
extract_sequence seq
(* Sequentialization of a function definition *)
let fundecl f =
Proc.contains_calls := false;
let rargs =
List.map
(fun (id, ty) -> let r = Reg.newv ty in name_regs id r; r)
f.Cmm.fun_args in
let rarg = Array.concat rargs in
let loc_arg = Proc.loc_parameters rarg in
let env =
List.fold_right2
(fun (id, ty) r env -> Tbl.add id r env)
f.Cmm.fun_args rargs Tbl.empty in
let seq = new_sequence() in
insert_moves loc_arg rarg seq;
emit_tail env f.Cmm.fun_body seq;
{ fun_name = f.Cmm.fun_name;
fun_args = loc_arg;
fun_body = extract_sequence seq;
fun_fast = f.Cmm.fun_fast }