+ support for implementing Objective-C classes in Pascal,

based on patch by Dmitry Boyarintsev (mantis #14508)
   o Todo: while parsing the class declaration, check whether the
       field types are valid for use in an obj-c class
  * use a common pool for selector names generated by objcselector()
    and by the rtti info for implemented classes

git-svn-id: branches/objc@13663 -

compiler/aasmdata.pas

@@ -65,6 +65,9 @@ interface
         al_resourcestrings,
         { Objective-C related sections }
         al_objc_data,
+        { keep pool data separate, so we can generate new pool entries
+          while emitting other data }
+        al_objc_pools,
         al_end
       );
 
@@ -79,8 +82,10 @@ interface
          sp_ansistr,
          sp_widestr,
          sp_unicodestr,
-         sp_objcselector,
+         sp_objcmetaclass,
-         sp_objcmetaclass
+         sp_objcvarnames,
+         sp_objcvartypes,
+         sp_objcclassnames
       );
       
     const
@@ -104,6 +109,7 @@ interface
         'al_picdata',
         'al_resourcestrings',
         'al_objc_data',
+        'al_objc_pools',
         'al_end'
       );
 

compiler/ncgobjc.pas

@@ -61,9 +61,9 @@ procedure tcgobjcselectornode.pass_generate_code;
     name   : pshortstring;
     pc     : pchar;
   begin
-    if current_asmdata.ConstPools[sp_objcselector]=nil then
+    if current_asmdata.ConstPools[sp_objcvarnames]=nil then
-      current_asmdata.ConstPools[sp_objcselector]:=THashSet.Create(64, True, False);
+      current_asmdata.ConstPools[sp_objcvarnames]:=THashSet.Create(64, True, False);
-    pool:=current_asmdata.ConstPools[sp_objcselector];
+    pool:=current_asmdata.ConstPools[sp_objcvarnames];
 
     case left.nodetype of
       loadn:

compiler/objcgutl.pas

@@ -6,7 +6,7 @@
 
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
-    the Free Software Foundation; either version 2 of the License, or
+    the Free Software Foundation; either version 2 of the License,or
     (at your option) any later version.
 
     This program is distributed in the hope that it will be useful,
@@ -27,21 +27,31 @@ unit objcgutl;
 
 interface
 
-uses
+  uses
-  cclasses,
+    cclasses,
-  aasmbase;
+    aasmbase,
+    symbase;
 
-procedure objcfinishstringrefpoolentry(entry: phashsetitem; refsec, stringsec: tasmsectiontype);
+  procedure objcfinishstringrefpoolentry(entry: phashsetitem; refsec, stringsec: tasmsectiontype);
+
+  procedure MaybeGenerateObjectiveCImageInfo(globalst, localst: tsymtable);
 
 
 implementation
 
-uses
+  uses
-  globtype,
+    globtype,globals,
-  aasmdata,aasmtai,
+    systems,
-  cgbase,cgutils,
+    aasmdata,aasmtai,
-  symsym,
+    cgbase,cgutils,
-  verbose;
+    objcutil,
+    symconst,symtype,symsym,symdef,symtable,
+    verbose;
+
+
+{******************************************************************
+                       String section helpers
+*******************************************************************}
 
 procedure objcfinishstringrefpoolentry(entry: phashsetitem; refsec, stringsec: tasmsectiontype);
   var
@@ -62,15 +72,412 @@ procedure objcfinishstringrefpoolentry(entry: phashsetitem; refsec, stringsec: t
         move(entry^.key^,pc^,entry^.keylength);
         pc[entry^.keylength]:=#0;
         { add a pointer to the message name in the string references section }
-        new_section(current_asmdata.asmlists[al_objc_data],refsec,reflab.name,sizeof(pint));
+        new_section(current_asmdata.asmlists[al_objc_pools],refsec,reflab.name,sizeof(pint));
-        current_asmdata.asmlists[al_objc_data].concat(Tai_label.Create(reflab));
+        current_asmdata.asmlists[al_objc_pools].concat(Tai_label.Create(reflab));
-        current_asmdata.asmlists[al_objc_data].concat(Tai_const.Create_sym(strlab));
+        current_asmdata.asmlists[al_objc_pools].concat(Tai_const.Create_sym(strlab));
 
         { and now add the message name to the associated strings section }
-        new_section(current_asmdata.asmlists[al_objc_data],stringsec,strlab.name,1);
+        new_section(current_asmdata.asmlists[al_objc_pools],stringsec,strlab.name,sizeof(pint));
-        current_asmdata.asmlists[al_objc_data].concat(Tai_label.Create(strlab));
+        current_asmdata.asmlists[al_objc_pools].concat(Tai_label.Create(strlab));
-        current_asmdata.asmlists[al_objc_data].concat(Tai_string.Create_pchar(pc,entry^.keylength+1));
+        current_asmdata.asmlists[al_objc_pools].concat(Tai_string.Create_pchar(pc,entry^.keylength+1));
     end;
   end;
 
+
+function objcreatestringpoolentry(const s: string; pooltype: tconstpooltype; stringsec: tasmsectiontype): TAsmSymbol;
+  var
+    entry  : PHashSetItem;
+    strlab : tasmlabel;
+    pc     : pchar;
+    pool   : THashSet;
+  begin
+    if current_asmdata.ConstPools[pooltype]=nil then
+       current_asmdata.ConstPools[pooltype]:=THashSet.Create(64, True, False);
+    pool := current_asmdata.constpools[pooltype];
+
+    entry:=pool.FindOrAdd(@s[1],length(s));
+    if not assigned(entry^.data) then
+      begin
+        { create new entry }
+        current_asmdata.getlabel(strlab,alt_data);
+        entry^.Data:=strlab;
+        getmem(pc,entry^.keylength+1);
+        move(entry^.key^,pc^,entry^.keylength);
+        pc[entry^.keylength]:=#0;
+
+        { add the string to the approriate section }
+        new_section(current_asmdata.asmlists[al_objc_pools],stringsec,strlab.name,sizeof(pint));
+        current_asmdata.asmlists[al_objc_pools].concat(Tai_label.Create(strlab));
+        current_asmdata.asmlists[al_objc_pools].concat(Tai_string.Create_pchar(pc,entry^.keylength+1));
+        Result := strlab;
+      end
+    else
+      Result := TAsmLabel(Entry^.Data);
+  end;
+
+
+{******************************************************************
+                        RTTI generation
+*******************************************************************}
+
+{ generate a method list, either of class methods or of instance methods,
+  and both for obj-c classes and categories. }
+procedure gen_objc1_methods(list: tasmlist; objccls: tobjectdef; out methodslabel: tasmlabel; classmethods, iscategory: Boolean);
+  const
+    clsSectType : array [Boolean] of tasmsectiontype = (sec_objc_inst_meth, sec_objc_cls_meth);
+    clsSectName : array [Boolean] of string = ('_OBJC_INST_METH','_OBJC_CLS_METH');
+    catSectType : array [Boolean] of tasmsectiontype = (sec_objc_cat_inst_meth, sec_objc_cat_cls_meth);
+    catSectName : array [Boolean] of string = ('_OBJC_CAT_INST_METH','_OBJC_CAT_CLS_METH');
+  type
+    method_data = record
+      def     : tprocdef;
+      selsym  : TAsmSymbol;
+      encsym  : TAsmSymbol;
+    end;
+  var
+    i     : Integer;
+    def   : tprocdef;
+    defs  : array of method_data;
+    mcnt  : integer;
+  begin
+    methodslabel:=nil;
+    mcnt:=0;
+    { collect all instance/class methods }
+    SetLength(defs,objccls.vmtentries.count);
+    for i:=0 to objccls.vmtentries.count-1 do
+      begin
+        def:=pvmtentry(objccls.vmtentries[i])^.procdef;
+        if Assigned(def.procstarttai) and
+           (classmethods = (po_classmethod in def.procoptions)) then
+          begin
+            defs[mcnt].def:=def;
+            defs[mcnt].selsym:=objcreatestringpoolentry(def.messageinf.str^,sp_objcvarnames,sec_objc_meth_var_names);
+            defs[mcnt].encsym:=objcreatestringpoolentry(objcencodemethod(def),sp_objcvartypes,sec_objc_meth_var_types);
+            inc(mcnt);
+          end;
+      end;
+    if mcnt=0 then
+      exit;
+
+    if iscategory then
+      new_section(list,clsSectType[classmethods],clsSectName[classmethods],4)
+    else
+      new_section(list,catSectType[classmethods],catSectName[classmethods],4);
+
+    current_asmdata.getlabel(methodslabel,alt_data);
+    list.Concat(tai_label.Create(methodslabel));
+
+    { not used, always zero }
+    list.Concat(tai_const.Create_32bit(0));
+    { number of objc_method entries in the method_list array }
+    list.Concat(tai_const.Create_32bit(mcnt));
+    for i := 0 to mcnt - 1 do
+      begin
+        { reference to the selector name }
+        list.Concat(tai_const.Create_sym(defs[i].selsym));
+        { reference to the obj-c encoded function parameters (signature) }
+        list.Concat(tai_const.Create_sym(defs[i].encsym));
+        { mangled name of the method }
+        list.Concat(tai_const.Create_sym(
+          current_asmdata.GetAsmSymbol(defs[i].def.objcmangledname)));
+      end;
+  end;
+
+
+{ generate an instance variables list for an obj-c class. }
+procedure gen_objc1_ivars(list: TAsmList; objccls: tobjectdef; out ivarslabel: TAsmLabel);
+  type
+    ivar_data = record
+      vf      : tfieldvarsym;
+      namesym : TAsmSymbol;
+      typesym : TAsmSymbol;
+    end;
+  var
+    i     : integer;
+    vf    : tfieldvarsym;
+    vars  : array of ivar_data;
+    vcnt  : Integer;
+    enctype : ansistring;
+    encerr  : tdef;
+  begin
+    ivarslabel:=nil;
+
+    vcnt:=0;
+    setLength(vars,objccls.symtable.SymList.Count);
+
+    for i:=0 to objccls.symtable.SymList.Count-1 do
+      if tsym(objccls.symtable.SymList[i]).typ=fieldvarsym then
+        begin
+          vf:=tfieldvarsym(objccls.symtable.SymList[i]);
+          if objctryencodetype(vf.vardef,enctype,encerr) then
+            begin
+              vars[vcnt].vf:=vf;
+              vars[vcnt].namesym:=objcreatestringpoolentry(vf.RealName,sp_objcvarnames,sec_objc_meth_var_names);
+              vars[vcnt].typesym:=objcreatestringpoolentry(enctype,sp_objcvartypes,sec_objc_meth_var_types);
+              inc(vcnt);
+            end
+          else
+            { must be caught during parsing }
+            internalerror(2009090601);
+        end;
+    if vcnt=0 then
+      exit;
+
+    new_section(list,sec_objc_instance_vars,'_OBJC_INSTANCE_VARS',sizeof(pint));
+
+    current_asmdata.getlabel(ivarslabel,alt_data);
+    list.Concat(tai_label.Create(ivarslabel));
+
+    { objc_ivar_list: first the number of elements }
+    list.Concat(tai_const.Create_32bit(vcnt));
+
+    for i:=0 to vcnt-1 do
+      begin
+        { reference to the instance variable name }
+        list.Concat(tai_const.Create_sym(vars[i].namesym));
+        { reference to the encoded type }
+        list.Concat(tai_const.Create_sym(vars[i].typesym));
+        { and the offset of the field }
+        list.Concat(tai_const.Create_32bit(vars[i].vf.fieldoffset));
+      end;
+  end;
+
+
+(*
+From Clang:
+
+  struct _objc_class {
+    Class isa;
+    Class super_class;
+    const char *name;
+    long version;
+    long info;
+    long instance_size;
+    struct _objc_ivar_list *ivars;
+    struct _objc_method_list *methods;
+    struct _objc_cache *cache;
+    struct _objc_protocol_list *protocols;
+    // Objective-C 1.0 extensions (<rdr://4585769>) -- for garbage collection
+    const char *ivar_layout;
+    struct _objc_class_ext *ext;
+  };
+*)
+
+{ Generate rtti for an Objective-C class and its meta-class. }
+procedure gen_objc1_classes_sections(list:TAsmList; objclss: tobjectdef; out classlabel: TAsmSymbol);
+  const
+    CLS_CLASS = 1;
+    CLS_META  = 2;
+    META_INST_SIZE = 40+8; // sizeof(objc_class) + 8
+  var
+    root          : tobjectdef;
+    lbl, metalbl  : TAsmLabel;
+    superStrSym,
+    classStrSym,
+    metaisaStrSym : TAsmSymbol;
+    mthdlist,
+    ivarslist     : TAsmLabel;
+  begin
+    { generate the class methods list }
+    gen_objc1_methods(list,objclss,mthdlist,true,false);
+
+    { register necessary names }
+    { 1) the superclass }
+    if assigned(objclss.childof) then
+      superStrSym:=objcreatestringpoolentry(objclss.childof.objextname^,sp_objcclassnames,sec_objc_class_names)
+    else
+      { not empty string, but nil! }
+      superStrSym:=nil;
+
+    { 2) the current class }
+    classStrSym:=objcreatestringpoolentry(objclss.objextname^,sp_objcclassnames,sec_objc_class_names);
+    { 3) the isa }
+    { From Clang: The isa for the meta-class is the root of the hierarchy. }
+    root:=objclss;
+    while assigned(root.childof) do
+      root:=root.childof;
+    metaisaStrSym:=objcreatestringpoolentry(root.objextname^,sp_objcclassnames,sec_objc_class_names);
+
+    { class declaration section }
+    new_section(list,sec_objc_meta_class,'_OBJC_META_CLASS',sizeof(pint));
+
+    { 1) meta-class declaration }
+    current_asmdata.getlabel(metalbl,alt_data);
+    list.Concat(tai_label.Create(metalbl));
+
+    list.Concat(Tai_const.Create_sym(metaisaStrSym));
+    { pointer to the superclass name if any, otherwise nil }
+    if assigned(superstrsym) then
+      list.Concat(Tai_const.Create_sym(superStrSym))
+    else
+      list.concat(tai_const.create_32bit(0));
+    { pointer to the class name }
+    list.Concat(Tai_const.Create_sym(classStrSym));
+
+    { version is always 0 currently }
+    list.Concat(Tai_const.Create_32bit(0));
+    { CLS_META for meta-classes }
+    list.Concat(Tai_const.Create_32bit(CLS_META));
+    { size of the meta-class instance: sizeof(objc_class) + 8 bytes }
+    list.Concat(Tai_const.Create_32bit(META_INST_SIZE) );
+    { meta-classes don't have ivars list (=0) }
+    list.Concat(Tai_const.Create_32bit(0));
+    { class methods list (stored in "__cls_meth" section) }
+    if Assigned(mthdlist) then
+      list.Concat(Tai_const.Create_sym(mthdlist))
+    else
+      list.Concat(Tai_const.Create_32bit(0));
+    { From Clang: cache is always nil }
+    list.Concat(Tai_const.Create_32bit(0));
+    { TODO: protocols }
+    list.Concat(Tai_const.Create_32bit(0));
+    { From Clang: ivar_layout for meta-class is always NULL. }
+    list.Concat(Tai_const.Create_32bit(0));
+    { From Clang: The class extension is always unused for meta-classes. }
+    list.Concat(Tai_const.Create_32bit(0));
+
+    { 2) regular class declaration }
+
+    { generate the instance methods list }
+    gen_objc1_methods(list,objclss,mthdlist,false,false);
+    { generate the instance variables list }
+    gen_objc1_ivars(list,objclss,ivarslist);
+
+    new_section(list,sec_objc_class,'_OBJC_CLASS',sizeof(pint));
+
+    current_asmdata.getlabel(lbl,alt_data);
+    list.Concat(tai_label.Create(lbl));
+
+    { for class declaration: the is points to the meta-class declaration }
+    list.Concat(Tai_const.Create_sym(metalbl));
+    { pointer to the super_class name if any, nil otherwise }
+    if assigned(superStrSym) then
+      list.Concat(Tai_const.Create_sym(superStrSym))
+    else
+      list.Concat(Tai_const.Create_32bit(0));
+    { pointer to the class name }
+    list.Concat(Tai_const.Create_sym(classStrSym));
+    { version is always 0 currently }
+    list.Concat(Tai_const.Create_32bit(0));
+    { CLS_CLASS for classes }
+    list.Concat(Tai_const.Create_32bit(CLS_CLASS));
+    { size of instance: total size of instance variables }
+    list.Concat(Tai_const.Create_32bit(tobjectsymtable(objclss.symtable).datasize));
+    { objc_ivar_list (stored in "__instance_vars" section) }
+    if assigned(ivarslist) then
+      list.Concat(Tai_const.Create_sym(ivarslist))
+    else
+      list.Concat(tai_const.create_32bit(0));
+    { instance methods list (stored in "__inst_meth" section) }
+    if Assigned(mthdlist) then
+      list.Concat(Tai_const.Create_sym(mthdlist))
+    else
+      list.Concat(Tai_const.Create_32bit(0));
+    { From Clang: cache is always NULL }
+    list.Concat(Tai_const.Create_32bit(0));
+    { TODO: protocols }
+    list.Concat(Tai_const.Create_32bit(0));
+    { TODO: From Clang: strong ivar_layout, necessary for garbage collection support }
+    list.Concat(Tai_const.Create_32bit(0));
+    { TODO: From Clang: weak ivar_layout, necessary for garbage collection support }
+    list.Concat(Tai_const.Create_32bit(0));
+
+    classlabel:=lbl;
+  end;
+
+
+{ Generate the rtti sections for all obj-c classes defined in st, and return
+  these classes in the classes list. }
+procedure gen_objc1_rtti_sections(list:TAsmList; st:TSymtable; var classes: tfpobjectlist);
+  var
+    i: longint;
+    def: tdef;
+    sym : TAsmSymbol;
+  begin
+    if not Assigned(st) then
+      exit;
+
+    for i:=0 to st.DefList.Count-1 do
+      begin
+        def:=tdef(st.DefList[i]);
+        if is_objcclass(def) and
+           not(oo_is_external in tobjectdef(def).objectoptions) then
+          begin
+            gen_objc1_classes_sections(list,tobjectdef(def),sym);
+            classes.add(sym);
+          end;
+      end;
+  end;
+
+
+{ Generate the global information sections (objc_symbols and objc_module_info)
+  for this module. }
+procedure gen_objc1_info_sections(list: tasmlist; classes: tfpobjectlist);
+  var
+    i: longint;
+    sym : TAsmSymbol;
+  begin
+    if (classes.count<>0) then
+      begin
+        new_section(list,sec_objc_symbols,'_OBJC_SYMBOLS',sizeof(pint));
+        sym := current_asmdata.RefAsmSymbol(target_asm.labelprefix+'_OBJC_SYMBOLS');
+
+        { symbol to refer to this information }
+        list.Concat(tai_symbol.Create(sym,0));
+        { ??? (always 0 in Clang) }
+        list.Concat(Tai_const.Create_pint(0));
+        { ??? (From Clang: always 0, pointer to some selector) }
+        list.Concat(Tai_const.Create_pint(0));
+        { From Clang: number of defined classes }
+        list.Concat(Tai_const.Create_16bit(classes.count));
+        { From Clang: number of defined categories }
+        list.Concat(Tai_const.Create_16bit(0));
+        { first all classes }
+        for i:=0 to classes.count-1 do
+          list.Concat(Tai_const.Create_sym(tasmsymbol(classes[i])));
+        { then all categories }
+     end
+    else
+      sym:=nil;
+
+    new_section(list,sec_objc_module_info,'_OBJC_MODULE_INFO',4);
+    { version number = 7 (always, both for gcc and clang, regardless of objc-1 or 2 }
+    list.Concat(Tai_const.Create_pint(7));
+    { sizeof(objc_module): 4 pointer-size entities }
+    list.Concat(Tai_const.Create_pint(sizeof(pint)*4));
+    { used to be file name, now unused (points to empty string) }
+    list.Concat(Tai_const.Create_sym(objcreatestringpoolentry('',sp_objcclassnames,sec_objc_class_names)));
+    { pointer to classes/categories list declared in this module }
+    if assigned(sym) then
+      list.Concat(Tai_const.Create_sym(sym))
+    else
+      list.concat(tai_const.create_pint(0));
+  end;
+
+
+procedure MaybeGenerateObjectiveCImageInfo(globalst, localst: tsymtable);
+  var
+    classes: tfpobjectlist;
+  begin
+    if (m_objectivec1 in current_settings.modeswitches) then
+      begin
+        { first 4 bytes contain version information about this section (currently version 0),
+          next 4 bytes contain flags (currently only regarding whether the code in the object
+          file supports or requires garbage collection)
+        }
+        new_section(current_asmdata.asmlists[al_objc_data],sec_objc_image_info,'_OBJC_IMAGE_INFO',sizeof(pint));
+        current_asmdata.asmlists[al_objc_data].concat(Tai_symbol.Createname(target_asm.labelprefix+'_OBJC_IMAGE_INFO',AT_LABEL,sizeof(pint)));
+        current_asmdata.asmlists[al_objc_data].concat(Tai_const.Create_64bit(0));
+
+        { generate rtti for all obj-c classes, protocols (todo) and categories (todo)
+          defined in this module. }
+        classes:=tfpobjectlist.create(false);
+        gen_objc1_rtti_sections(current_asmdata.asmlists[al_objc_data],globalst,classes);
+        gen_objc1_rtti_sections(current_asmdata.asmlists[al_objc_data],localst,classes);
+        gen_objc1_info_sections(current_asmdata.asmlists[al_objc_data],classes);
+        classes.free;
+      end;
+  end;
+
+
 end.

compiler/pmodules.pas

@@ -45,6 +45,7 @@ implementation
        link,assemble,import,export,gendef,ppu,comprsrc,dbgbase,
        cresstr,procinfo,
        pexports,
+       objcgutl,
        wpobase,
        scanner,pbase,pexpr,psystem,psub,pdecsub,ptype
        ,cpuinfo
@@ -236,21 +237,6 @@ implementation
       end;
 
 
-    procedure MaybeGenerateObjectiveCImageInfo;
-      begin
-        if (m_objectivec1 in current_settings.modeswitches) then
-          begin
-            { first 4 bytes contain version information about this section (currently version 0),
-              next 4 bytes contain flags (currently only regarding whether the code in the object
-              file supports or requires garbage collection)
-            }
-            new_section(current_asmdata.asmlists[al_objc_data],sec_objc_image_info,'_OBJC_IMAGE_INFO',4);
-            current_asmdata.asmlists[al_objc_data].concat(Tai_symbol.Createname(target_asm.labelprefix+'_OBJC_IMAGE_INFO',AT_LABEL,8));
-            current_asmdata.asmlists[al_objc_data].concat(Tai_const.Create_64bit(0));
-          end;
-      end;
-
-
     Function CheckResourcesUsed : boolean;
     var
       hp           : tused_unit;
@@ -1216,8 +1202,8 @@ implementation
             exit;
           end;
 
-         { if an Objective-C module, generate objc_image_info section }
+         { if an Objective-C module, generate rtti and module info }
-         MaybeGenerateObjectiveCImageInfo;
+         MaybeGenerateObjectiveCImageInfo(current_module.globalsymtable,current_module.localsymtable);
 
          { do we need to add the variants unit? }
          maybeloadvariantsunit;
@@ -2154,9 +2140,6 @@ implementation
                 end;
           end;
 
-         { if an Objective-C module, generate objc_image_info section }
-         MaybeGenerateObjectiveCImageInfo;
-
          { do we need to add the variants unit? }
          maybeloadvariantsunit;
 
@@ -2186,6 +2169,9 @@ implementation
          { generate rtti/init tables }
          write_persistent_type_info(current_module.localsymtable);
 
+         { if an Objective-C module, generate rtti and module info }
+         MaybeGenerateObjectiveCImageInfo(nil,current_module.localsymtable);
+
          { generate wrappers for interfaces }
          gen_intf_wrappers(current_asmdata.asmlists[al_procedures],current_module.localsymtable);