ocaml/asmcomp/asmlink.ml

462 lines
17 KiB
OCaml

(**************************************************************************)
(* *)
(* OCaml *)
(* *)
(* Xavier Leroy, projet Cristal, INRIA Rocquencourt *)
(* *)
(* Copyright 1996 Institut National de Recherche en Informatique et *)
(* en Automatique. *)
(* *)
(* All rights reserved. This file is distributed under the terms of *)
(* the GNU Lesser General Public License version 2.1, with the *)
(* special exception on linking described in the file LICENSE. *)
(* *)
(**************************************************************************)
(* Link a set of .cmx/.o files and produce an executable *)
open Misc
open Config
open Cmx_format
open Compilenv
module String = Misc.Stdlib.String
type error =
| File_not_found of filepath
| Not_an_object_file of filepath
| Missing_implementations of (modname * string list) list
| Inconsistent_interface of modname * filepath * filepath
| Inconsistent_implementation of modname * filepath * filepath
| Assembler_error of filepath
| Linking_error of int
| Multiple_definition of modname * filepath * filepath
| Missing_cmx of filepath * modname
exception Error of error
(* Consistency check between interfaces and implementations *)
module Cmi_consistbl = Consistbl.Make (Misc.Stdlib.String)
let crc_interfaces = Cmi_consistbl.create ()
let interfaces = ref ([] : string list)
module Cmx_consistbl = Consistbl.Make (Misc.Stdlib.String)
let crc_implementations = Cmx_consistbl.create ()
let implementations = ref ([] : string list)
let implementations_defined = ref ([] : (string * string) list)
let cmx_required = ref ([] : string list)
let check_consistency file_name unit crc =
begin try
List.iter
(fun (name, crco) ->
interfaces := name :: !interfaces;
match crco with
None -> ()
| Some crc ->
if name = unit.ui_name
then Cmi_consistbl.set crc_interfaces name crc file_name
else Cmi_consistbl.check crc_interfaces name crc file_name)
unit.ui_imports_cmi
with Cmi_consistbl.Inconsistency {
unit_name = name;
inconsistent_source = user;
original_source = auth;
} ->
raise(Error(Inconsistent_interface(name, user, auth)))
end;
begin try
List.iter
(fun (name, crco) ->
implementations := name :: !implementations;
match crco with
None ->
if List.mem name !cmx_required then
raise(Error(Missing_cmx(file_name, name)))
| Some crc ->
Cmx_consistbl.check crc_implementations name crc file_name)
unit.ui_imports_cmx
with Cmx_consistbl.Inconsistency {
unit_name = name;
inconsistent_source = user;
original_source = auth;
} ->
raise(Error(Inconsistent_implementation(name, user, auth)))
end;
begin try
let source = List.assoc unit.ui_name !implementations_defined in
raise (Error(Multiple_definition(unit.ui_name, file_name, source)))
with Not_found -> ()
end;
implementations := unit.ui_name :: !implementations;
Cmx_consistbl.set crc_implementations unit.ui_name crc file_name;
implementations_defined :=
(unit.ui_name, file_name) :: !implementations_defined;
if unit.ui_symbol <> unit.ui_name then
cmx_required := unit.ui_name :: !cmx_required
let extract_crc_interfaces () =
Cmi_consistbl.extract !interfaces crc_interfaces
let extract_crc_implementations () =
Cmx_consistbl.extract !implementations crc_implementations
(* Add C objects and options and "custom" info from a library descriptor.
See bytecomp/bytelink.ml for comments on the order of C objects. *)
let lib_ccobjs = ref []
let lib_ccopts = ref []
let add_ccobjs origin l =
if not !Clflags.no_auto_link then begin
lib_ccobjs := l.lib_ccobjs @ !lib_ccobjs;
let replace_origin =
Misc.replace_substring ~before:"$CAMLORIGIN" ~after:origin
in
lib_ccopts := List.map replace_origin l.lib_ccopts @ !lib_ccopts
end
let runtime_lib () =
let libname = "libasmrun" ^ !Clflags.runtime_variant ^ ext_lib in
try
if !Clflags.nopervasives || not !Clflags.with_runtime then []
else [ Load_path.find libname ]
with Not_found ->
raise(Error(File_not_found libname))
let object_file_name name =
let file_name =
try
Load_path.find name
with Not_found ->
fatal_errorf "Asmlink.object_file_name: %s not found" name in
if Filename.check_suffix file_name ".cmx" then
Filename.chop_suffix file_name ".cmx" ^ ext_obj
else if Filename.check_suffix file_name ".cmxa" then
Filename.chop_suffix file_name ".cmxa" ^ ext_lib
else
fatal_error "Asmlink.object_file_name: bad ext"
(* First pass: determine which units are needed *)
let missing_globals = (Hashtbl.create 17 : (string, string list ref) Hashtbl.t)
let is_required name =
try ignore (Hashtbl.find missing_globals name); true
with Not_found -> false
let add_required by (name, _crc) =
try
let rq = Hashtbl.find missing_globals name in
rq := by :: !rq
with Not_found ->
Hashtbl.add missing_globals name (ref [by])
let remove_required name =
Hashtbl.remove missing_globals name
let extract_missing_globals () =
let mg = ref [] in
Hashtbl.iter (fun md rq -> mg := (md, !rq) :: !mg) missing_globals;
!mg
type file =
| Unit of string * unit_infos * Digest.t
| Library of string * library_infos
let read_file obj_name =
let file_name =
try
Load_path.find obj_name
with Not_found ->
raise(Error(File_not_found obj_name)) in
if Filename.check_suffix file_name ".cmx" then begin
(* This is a .cmx file. It must be linked in any case.
Read the infos to see which modules it requires. *)
let (info, crc) = read_unit_info file_name in
Unit (file_name,info,crc)
end
else if Filename.check_suffix file_name ".cmxa" then begin
let infos =
try read_library_info file_name
with Compilenv.Error(Not_a_unit_info _) ->
raise(Error(Not_an_object_file file_name))
in
Library (file_name,infos)
end
else raise(Error(Not_an_object_file file_name))
let scan_file obj_name (tolink, objfiles) = match read_file obj_name with
| Unit (file_name,info,crc) ->
(* This is a .cmx file. It must be linked in any case. *)
remove_required info.ui_name;
List.iter (add_required file_name) info.ui_imports_cmx;
((info, file_name, crc) :: tolink, obj_name :: objfiles)
| Library (file_name,infos) ->
(* This is an archive file. Each unit contained in it will be linked
in only if needed. *)
add_ccobjs (Filename.dirname file_name) infos;
let tolink =
List.fold_right
(fun (info, crc) reqd ->
if info.ui_force_link
|| !Clflags.link_everything
|| is_required info.ui_name
then begin
remove_required info.ui_name;
List.iter (add_required (Printf.sprintf "%s(%s)"
file_name info.ui_name))
info.ui_imports_cmx;
(info, file_name, crc) :: reqd
end else
reqd)
infos.lib_units tolink
and objfiles =
if infos.lib_units = []
&& not (Sys.file_exists (object_file_name obj_name)) then
(* MSVC doesn't support empty .lib files, and macOS struggles to make
them (#6550), so there shouldn't be one if the .cmxa contains no
units. The file_exists check is added to be ultra-defensive for the
case where a user has manually added things to the .a/.lib file *)
objfiles
else
obj_name :: objfiles
in (tolink, objfiles)
(* Second pass: generate the startup file and link it with everything else *)
let force_linking_of_startup ~ppf_dump =
Asmgen.compile_phrase ~ppf_dump
(Cmm.Cdata ([Cmm.Csymbol_address "caml_startup"]))
let make_globals_map units_list ~crc_interfaces =
let crc_interfaces = String.Tbl.of_seq (List.to_seq crc_interfaces) in
let defined =
List.map (fun (unit, _, impl_crc) ->
let intf_crc = String.Tbl.find crc_interfaces unit.ui_name in
String.Tbl.remove crc_interfaces unit.ui_name;
(unit.ui_name, intf_crc, Some impl_crc, unit.ui_defines))
units_list
in
String.Tbl.fold (fun name intf acc ->
(name, intf, None, []) :: acc)
crc_interfaces defined
let make_startup_file ~ppf_dump units_list ~crc_interfaces =
let compile_phrase p = Asmgen.compile_phrase ~ppf_dump p in
Location.input_name := "caml_startup"; (* set name of "current" input *)
Compilenv.reset "_startup";
(* set the name of the "current" compunit *)
Emit.begin_assembly ();
let name_list =
List.flatten (List.map (fun (info,_,_) -> info.ui_defines) units_list) in
compile_phrase (Cmm_helpers.entry_point name_list);
let units = List.map (fun (info,_,_) -> info) units_list in
List.iter compile_phrase (Cmm_helpers.generic_functions false units);
Array.iteri
(fun i name -> compile_phrase (Cmm_helpers.predef_exception i name))
Runtimedef.builtin_exceptions;
compile_phrase (Cmm_helpers.global_table name_list);
let globals_map = make_globals_map units_list ~crc_interfaces in
compile_phrase (Cmm_helpers.globals_map globals_map);
compile_phrase(Cmm_helpers.data_segment_table ("_startup" :: name_list));
if !Clflags.function_sections then
compile_phrase
(Cmm_helpers.code_segment_table("_hot" :: "_startup" :: name_list))
else
compile_phrase(Cmm_helpers.code_segment_table("_startup" :: name_list));
let all_names = "_startup" :: "_system" :: name_list in
compile_phrase (Cmm_helpers.frame_table all_names);
if !Clflags.output_complete_object then
force_linking_of_startup ~ppf_dump;
Emit.end_assembly ()
let make_shared_startup_file ~ppf_dump units =
let compile_phrase p = Asmgen.compile_phrase ~ppf_dump p in
Location.input_name := "caml_startup";
Compilenv.reset "_shared_startup";
Emit.begin_assembly ();
List.iter compile_phrase
(Cmm_helpers.generic_functions true (List.map fst units));
compile_phrase (Cmm_helpers.plugin_header units);
compile_phrase
(Cmm_helpers.global_table
(List.map (fun (ui,_) -> ui.ui_symbol) units));
if !Clflags.output_complete_object then
force_linking_of_startup ~ppf_dump;
(* this is to force a reference to all units, otherwise the linker
might drop some of them (in case of libraries) *)
Emit.end_assembly ()
let call_linker_shared file_list output_name =
let exitcode = Ccomp.call_linker Ccomp.Dll output_name file_list "" in
if not (exitcode = 0)
then raise(Error(Linking_error exitcode))
let link_shared ~ppf_dump objfiles output_name =
Profile.record_call output_name (fun () ->
let units_tolink, objfiles =
List.fold_right scan_file objfiles ([], [])
in
List.iter
(fun (info, file_name, crc) -> check_consistency file_name info crc)
units_tolink;
Clflags.ccobjs := !Clflags.ccobjs @ !lib_ccobjs;
Clflags.all_ccopts := !lib_ccopts @ !Clflags.all_ccopts;
let objfiles = List.rev_map object_file_name objfiles @
(List.rev !Clflags.ccobjs) in
let startup =
if !Clflags.keep_startup_file || !Emitaux.binary_backend_available
then output_name ^ ".startup" ^ ext_asm
else Filename.temp_file "camlstartup" ext_asm in
let startup_obj = output_name ^ ".startup" ^ ext_obj in
Asmgen.compile_unit
startup !Clflags.keep_startup_file startup_obj
(fun () ->
make_shared_startup_file ~ppf_dump
(List.map (fun (ui,_,crc) -> (ui,crc)) units_tolink)
);
call_linker_shared (startup_obj :: objfiles) output_name;
remove_file startup_obj
)
let call_linker file_list startup_file output_name =
let main_dll = !Clflags.output_c_object
&& Filename.check_suffix output_name Config.ext_dll
and main_obj_runtime = !Clflags.output_complete_object
in
let files = startup_file :: (List.rev file_list) in
let files, c_lib =
if (not !Clflags.output_c_object) || main_dll || main_obj_runtime then
files @ (List.rev !Clflags.ccobjs) @ runtime_lib (),
(if !Clflags.nopervasives || (main_obj_runtime && not main_dll)
then "" else Config.native_c_libraries)
else
files, ""
in
let mode =
if main_dll then Ccomp.MainDll
else if !Clflags.output_c_object then Ccomp.Partial
else Ccomp.Exe
in
let exitcode = Ccomp.call_linker mode output_name files c_lib in
if not (exitcode = 0)
then raise(Error(Linking_error exitcode))
(* Main entry point *)
let link ~ppf_dump objfiles output_name =
Profile.record_call output_name (fun () ->
let stdlib = "stdlib.cmxa" in
let stdexit = "std_exit.cmx" in
let objfiles =
if !Clflags.nopervasives then objfiles
else if !Clflags.output_c_object then stdlib :: objfiles
else stdlib :: (objfiles @ [stdexit]) in
let units_tolink, objfiles =
List.fold_right scan_file objfiles ([], [])
in
Array.iter remove_required Runtimedef.builtin_exceptions;
begin match extract_missing_globals() with
[] -> ()
| mg -> raise(Error(Missing_implementations mg))
end;
List.iter
(fun (info, file_name, crc) -> check_consistency file_name info crc)
units_tolink;
let crc_interfaces = extract_crc_interfaces () in
Clflags.ccobjs := !Clflags.ccobjs @ !lib_ccobjs;
Clflags.all_ccopts := !lib_ccopts @ !Clflags.all_ccopts;
(* put user's opts first *)
let startup =
if !Clflags.keep_startup_file || !Emitaux.binary_backend_available
then output_name ^ ".startup" ^ ext_asm
else Filename.temp_file "camlstartup" ext_asm in
let startup_obj = Filename.temp_file "camlstartup" ext_obj in
Asmgen.compile_unit
startup !Clflags.keep_startup_file startup_obj
(fun () -> make_startup_file ~ppf_dump units_tolink ~crc_interfaces);
Misc.try_finally
(fun () ->
call_linker (List.map object_file_name objfiles)
startup_obj output_name)
~always:(fun () -> remove_file startup_obj)
)
(* Error report *)
open Format
let report_error ppf = function
| File_not_found name ->
fprintf ppf "Cannot find file %s" name
| Not_an_object_file name ->
fprintf ppf "The file %a is not a compilation unit description"
Location.print_filename name
| Missing_implementations l ->
let print_references ppf = function
| [] -> ()
| r1 :: rl ->
fprintf ppf "%s" r1;
List.iter (fun r -> fprintf ppf ",@ %s" r) rl in
let print_modules ppf =
List.iter
(fun (md, rq) ->
fprintf ppf "@ @[<hov 2>%s referenced from %a@]" md
print_references rq) in
fprintf ppf
"@[<v 2>No implementations provided for the following modules:%a@]"
print_modules l
| Inconsistent_interface(intf, file1, file2) ->
fprintf ppf
"@[<hov>Files %a@ and %a@ make inconsistent assumptions \
over interface %s@]"
Location.print_filename file1
Location.print_filename file2
intf
| Inconsistent_implementation(intf, file1, file2) ->
fprintf ppf
"@[<hov>Files %a@ and %a@ make inconsistent assumptions \
over implementation %s@]"
Location.print_filename file1
Location.print_filename file2
intf
| Assembler_error file ->
fprintf ppf "Error while assembling %a" Location.print_filename file
| Linking_error exitcode ->
fprintf ppf "Error during linking (exit code %d)" exitcode
| Multiple_definition(modname, file1, file2) ->
fprintf ppf
"@[<hov>Files %a@ and %a@ both define a module named %s@]"
Location.print_filename file1
Location.print_filename file2
modname
| Missing_cmx(filename, name) ->
fprintf ppf
"@[<hov>File %a@ was compiled without access@ \
to the .cmx file@ for module %s,@ \
which was produced by `ocamlopt -for-pack'.@ \
Please recompile %a@ with the correct `-I' option@ \
so that %s.cmx@ is found.@]"
Location.print_filename filename name
Location.print_filename filename
name
let () =
Location.register_error_of_exn
(function
| Error err -> Some (Location.error_of_printer_file report_error err)
| _ -> None
)
let reset () =
Cmi_consistbl.clear crc_interfaces;
Cmx_consistbl.clear crc_implementations;
implementations_defined := [];
cmx_required := [];
interfaces := [];
implementations := [];
lib_ccobjs := [];
lib_ccopts := []