fpc/compiler/pparautl.pas
2015-12-26 20:48:50 +00:00

421 lines
17 KiB
ObjectPascal

{
Copyright (c) 1998-2002 by Florian Klaempfl, Daniel Mantione
Helpers for dealing with subroutine parameters during parsing
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
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
****************************************************************************
}
unit pparautl;
{$i fpcdefs.inc}
interface
uses
symdef;
procedure insert_funcret_para(pd:tabstractprocdef);
procedure insert_parentfp_para(pd:tabstractprocdef);
procedure insert_self_and_vmt_para(pd:tabstractprocdef);
procedure insert_funcret_local(pd:tprocdef);
procedure insert_hidden_para(p:TObject;arg:pointer);
procedure check_c_para(pd:Tabstractprocdef);
implementation
uses
globals,globtype,verbose,systems,
symconst,symtype,symbase,symsym,symtable,symcreat,defutil,blockutl,
paramgr;
procedure insert_funcret_para(pd:tabstractprocdef);
var
storepos : tfileposinfo;
vs : tparavarsym;
paranr : word;
begin
if not(pd.proctypeoption in [potype_constructor,potype_destructor]) and
not is_void(pd.returndef) and
not (df_generic in pd.defoptions) and
paramanager.ret_in_param(pd.returndef,pd) then
begin
storepos:=current_tokenpos;
if pd.typ=procdef then
current_tokenpos:=tprocdef(pd).fileinfo;
{$if defined(i386)}
{ For left to right add it at the end to be delphi compatible.
In the case of safecalls with safecal-exceptions support the
funcret-para is (from the 'c'-point of view) a normal parameter
which has to be added to the end of the parameter-list }
if (pd.proccalloption in (pushleftright_pocalls)) or
((tf_safecall_exceptions in target_info.flags) and
(pd.proccalloption=pocall_safecall)) then
paranr:=paranr_result_leftright
else
{$elseif defined(SUPPORT_SAFECALL)}
if (tf_safecall_exceptions in target_info.flags) and
(pd.proccalloption = pocall_safecall) then
paranr:=paranr_result_leftright
else
{$endif}
paranr:=paranr_result;
{ Generate result variable accessing function result }
vs:=cparavarsym.create('$result',paranr,vs_var,pd.returndef,[vo_is_funcret,vo_is_hidden_para]);
pd.parast.insert(vs);
{ Store this symbol as funcretsym for procedures }
if pd.typ=procdef then
tprocdef(pd).funcretsym:=vs;
current_tokenpos:=storepos;
end;
end;
procedure insert_parentfp_para(pd:tabstractprocdef);
var
storepos : tfileposinfo;
vs : tparavarsym;
paranr : longint;
begin
if pd.parast.symtablelevel>normal_function_level then
begin
storepos:=current_tokenpos;
if pd.typ=procdef then
current_tokenpos:=tprocdef(pd).fileinfo;
{ if no support for nested procvars is activated, use the old
calling convention to pass the parent frame pointer for backwards
compatibility }
if not(m_nested_procvars in current_settings.modeswitches) then
paranr:=paranr_parentfp
{ nested procvars require Delphi-style parentfp passing, see
po_delphi_nested_cc declaration for more info }
{$if defined(i386) or defined(i8086)}
else if (pd.proccalloption in pushleftright_pocalls) then
paranr:=paranr_parentfp_delphi_cc_leftright
{$endif i386 or i8086}
else
paranr:=paranr_parentfp_delphi_cc;
{ Generate frame pointer. It can't be put in a register since it
must be accessable from nested routines }
if not(target_info.system in systems_fpnestedstruct) or
{ in case of errors or declared procvardef types, prevent invalid
type cast and possible nil pointer dereference }
not assigned(pd.owner.defowner) or
(pd.owner.defowner.typ<>procdef) then
begin
vs:=cparavarsym.create('$parentfp',paranr,vs_value
,parentfpvoidpointertype,[vo_is_parentfp,vo_is_hidden_para]);
vs.varregable:=vr_none;
end
else
begin
if not assigned(tprocdef(pd.owner.defowner).parentfpstruct) then
build_parentfpstruct(tprocdef(pd.owner.defowner));
vs:=cparavarsym.create('$parentfp',paranr,vs_value
,tprocdef(pd.owner.defowner).parentfpstructptrtype,[vo_is_parentfp,vo_is_hidden_para]);
end;
pd.parast.insert(vs);
current_tokenpos:=storepos;
end;
end;
procedure insert_self_and_vmt_para(pd:tabstractprocdef);
var
storepos : tfileposinfo;
vs : tparavarsym;
hdef : tdef;
selfdef : tdef;
vsp : tvarspez;
aliasvs : tabsolutevarsym;
sl : tpropaccesslist;
begin
if (pd.typ=procdef) and
is_objc_class_or_protocol(tprocdef(pd).struct) and
(pd.parast.symtablelevel=normal_function_level) then
begin
{ insert Objective-C self and selector parameters }
vs:=cparavarsym.create('$_cmd',paranr_objc_cmd,vs_value,objc_seltype,[vo_is_msgsel,vo_is_hidden_para]);
pd.parast.insert(vs);
{ make accessible to code }
sl:=tpropaccesslist.create;
sl.addsym(sl_load,vs);
aliasvs:=cabsolutevarsym.create_ref('_CMD',objc_seltype,sl);
include(aliasvs.varoptions,vo_is_msgsel);
tlocalsymtable(tprocdef(pd).localst).insert(aliasvs);
if (po_classmethod in pd.procoptions) then
{ compatible with what gcc does }
hdef:=objc_idtype
else
hdef:=tprocdef(pd).struct;
vs:=cparavarsym.create('$self',paranr_objc_self,vs_value,hdef,[vo_is_self,vo_is_hidden_para]);
pd.parast.insert(vs);
end
else if (pd.typ=procvardef) and
pd.is_methodpointer then
begin
{ Generate self variable }
vs:=cparavarsym.create('$self',paranr_self,vs_value,voidpointertype,[vo_is_self,vo_is_hidden_para]);
pd.parast.insert(vs);
end
{ while only procvardefs of this type can be declared in Pascal code,
internally we also generate procdefs of this type when creating
block wrappers }
else if (po_is_block in pd.procoptions) then
begin
{ generate the first hidden parameter, which is a so-called "block
literal" describing the block and containing its invocation
procedure }
hdef:=cpointerdef.getreusable(get_block_literal_type_for_proc(pd));
{ mark as vo_is_parentfp so that proc2procvar comparisons will
succeed when assigning arbitrary routines to the block }
vs:=cparavarsym.create('$_block_literal',paranr_blockselfpara,vs_value,
hdef,[vo_is_hidden_para,vo_is_parentfp]
);
pd.parast.insert(vs);
if pd.typ=procdef then
begin
{ make accessible to code }
sl:=tpropaccesslist.create;
sl.addsym(sl_load,vs);
aliasvs:=cabsolutevarsym.create_ref('FPC_BLOCK_SELF',hdef,sl);
include(aliasvs.varoptions,vo_is_parentfp);
tlocalsymtable(tprocdef(pd).localst).insert(aliasvs);
end;
end
else
begin
if (pd.typ=procdef) and
assigned(tprocdef(pd).struct) and
(pd.parast.symtablelevel=normal_function_level) then
begin
{ static class methods have no hidden self/vmt pointer }
if pd.no_self_node then
exit;
storepos:=current_tokenpos;
current_tokenpos:=tprocdef(pd).fileinfo;
{ Generate VMT variable for constructor/destructor }
if (pd.proctypeoption in [potype_constructor,potype_destructor]) and
not(is_cppclass(tprocdef(pd).struct) or
is_record(tprocdef(pd).struct) or
is_javaclass(tprocdef(pd).struct) or
(
{ no vmt for record/type helper constructors }
is_objectpascal_helper(tprocdef(pd).struct) and
(tobjectdef(tprocdef(pd).struct).extendeddef.typ<>objectdef)
)) then
begin
vs:=cparavarsym.create('$vmt',paranr_vmt,vs_value,cclassrefdef.create(tprocdef(pd).struct),[vo_is_vmt,vo_is_hidden_para]);
pd.parast.insert(vs);
end;
{ for helpers the type of Self is equivalent to the extended
type or equal to an instance of it }
if is_objectpascal_helper(tprocdef(pd).struct) then
selfdef:=tobjectdef(tprocdef(pd).struct).extendeddef
else if is_objccategory(tprocdef(pd).struct) then
selfdef:=tobjectdef(tprocdef(pd).struct).childof
else
selfdef:=tprocdef(pd).struct;
{ Generate self variable, for classes we need
to use the generic voidpointer to be compatible with
methodpointers }
vsp:=vs_value;
if (po_staticmethod in pd.procoptions) or
(po_classmethod in pd.procoptions) then
hdef:=cclassrefdef.create(selfdef)
else
begin
if is_object(selfdef) or (selfdef.typ<>objectdef) then
vsp:=vs_var;
hdef:=selfdef;
end;
vs:=cparavarsym.create('$self',paranr_self,vsp,hdef,[vo_is_self,vo_is_hidden_para]);
pd.parast.insert(vs);
current_tokenpos:=storepos;
end;
end;
end;
procedure insert_funcret_local(pd:tprocdef);
var
storepos : tfileposinfo;
vs : tlocalvarsym;
aliasvs : tabsolutevarsym;
sl : tpropaccesslist;
hs : string;
begin
{ The result from constructors and destructors can't be accessed directly }
if not(pd.proctypeoption in [potype_constructor,potype_destructor]) and
not is_void(pd.returndef) then
begin
storepos:=current_tokenpos;
current_tokenpos:=pd.fileinfo;
{ We need to insert a varsym for the result in the localst
when it is returning in a register }
{ we also need to do this for a generic procdef as we didn't allow
the creation of a result symbol in insert_funcret_para, but we need
a valid funcretsym }
if (df_generic in pd.defoptions) or
not paramanager.ret_in_param(pd.returndef,pd) then
begin
vs:=clocalvarsym.create('$result',vs_value,pd.returndef,[vo_is_funcret],true);
pd.localst.insert(vs);
pd.funcretsym:=vs;
end;
{ insert the name of the procedure as alias for the function result,
we can't use realname because that will not work for compilerprocs
as the name is lowercase and unreachable from the code }
if (pd.proctypeoption<>potype_operator) or assigned(pd.resultname) then
begin
if assigned(pd.resultname) then
hs:=pd.resultname^
else
hs:=pd.procsym.name;
sl:=tpropaccesslist.create;
sl.addsym(sl_load,pd.funcretsym);
aliasvs:=cabsolutevarsym.create_ref(hs,pd.returndef,sl);
include(aliasvs.varoptions,vo_is_funcret);
tlocalsymtable(pd.localst).insert(aliasvs);
end;
{ insert result also if support is on }
if (m_result in current_settings.modeswitches) then
begin
sl:=tpropaccesslist.create;
sl.addsym(sl_load,pd.funcretsym);
aliasvs:=cabsolutevarsym.create_ref('RESULT',pd.returndef,sl);
include(aliasvs.varoptions,vo_is_funcret);
include(aliasvs.varoptions,vo_is_result);
tlocalsymtable(pd.localst).insert(aliasvs);
end;
current_tokenpos:=storepos;
end;
end;
procedure insert_hidden_para(p:TObject;arg:pointer);
var
hvs : tparavarsym;
pd : tabstractprocdef absolute arg;
begin
if (tsym(p).typ<>paravarsym) then
exit;
with tparavarsym(p) do
begin
{ We need a local copy for a value parameter when only the
address is pushed. Open arrays and Array of Const are
an exception because they are allocated at runtime and the
address that is pushed is patched.
Arrays passed to cdecl routines are special: they are pointers in
C and hence must be passed as such. Due to historical reasons, if
a cdecl routine is implemented in Pascal, we still make a copy on
the callee side. Do this the same on platforms that normally must
make a copy on the caller side, as otherwise the behaviour will
be different (and less perfomant) for routines implemented in C }
if (varspez=vs_value) and
paramanager.push_addr_param(varspez,vardef,pd.proccalloption) and
not(is_open_array(vardef) or
is_array_of_const(vardef)) and
(not(target_info.system in systems_caller_copy_addr_value_para) or
((pd.proccalloption in cdecl_pocalls) and
(vardef.typ=arraydef))) then
include(varoptions,vo_has_local_copy);
{ needs high parameter ? }
if paramanager.push_high_param(varspez,vardef,pd.proccalloption) then
begin
hvs:=cparavarsym.create('$high'+name,paranr+1,vs_const,ptrsinttype,[vo_is_high_para,vo_is_hidden_para]);
hvs.symoptions:=[];
owner.insert(hvs);
{ don't place to register if it will be accessed from implicit finally block }
if (varspez=vs_value) and
is_open_array(vardef) and
is_managed_type(vardef) then
hvs.varregable:=vr_none;
end
else
begin
{ Give a warning that cdecl routines does not include high()
support }
if (pd.proccalloption in cdecl_pocalls) and
paramanager.push_high_param(varspez,vardef,pocall_default) then
begin
if is_open_string(vardef) then
MessagePos(fileinfo,parser_w_cdecl_no_openstring);
if not(po_external in pd.procoptions) and
(pd.typ<>procvardef) and
not is_objc_class_or_protocol(tprocdef(pd).struct) then
if is_array_of_const(vardef) then
MessagePos(fileinfo,parser_e_varargs_need_cdecl_and_external)
else
MessagePos(fileinfo,parser_w_cdecl_has_no_high);
end;
if (vardef.typ=formaldef) and (Tformaldef(vardef).typed) then
begin
hvs:=cparavarsym.create('$typinfo'+name,paranr+1,vs_const,voidpointertype,
[vo_is_typinfo_para,vo_is_hidden_para]);
owner.insert(hvs);
end;
end;
end;
end;
procedure check_c_para(pd:Tabstractprocdef);
var
i,
lastparaidx : longint;
sym : TSym;
begin
lastparaidx:=pd.parast.SymList.Count-1;
for i:=0 to pd.parast.SymList.Count-1 do
begin
sym:=tsym(pd.parast.SymList[i]);
if (sym.typ=paravarsym) and
(tparavarsym(sym).vardef.typ=arraydef) then
begin
if not is_variant_array(tparavarsym(sym).vardef) and
not is_array_of_const(tparavarsym(sym).vardef) and
(tparavarsym(sym).varspez<>vs_var) then
MessagePos(tparavarsym(sym).fileinfo,parser_h_c_arrays_are_references);
if is_array_of_const(tparavarsym(sym).vardef) and
(i<lastparaidx) and
(tsym(pd.parast.SymList[i+1]).typ=paravarsym) and
not(vo_is_high_para in tparavarsym(pd.parast.SymList[i+1]).varoptions) then
MessagePos(tparavarsym(sym).fileinfo,parser_e_C_array_of_const_must_be_last);
end;
end;
end;
end.