fpc/compiler/pass_2.pas
1999-11-06 14:34:16 +00:00

785 lines
30 KiB
ObjectPascal

{
$Id$
Copyright (c) 1993-98 by Florian Klaempfl
This unit handles the codegeneration pass
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.
****************************************************************************
}
{$ifdef TP}
{$E+,F+,N+}
{$endif}
unit pass_2;
interface
uses
tree;
{ produces assembler for the expression in variable p }
{ and produces an assembler node at the end }
procedure generatecode(var p : ptree);
{ produces the actual code }
function do_secondpass(var p : ptree) : boolean;
procedure secondpass(var p : ptree);
implementation
uses
globtype,systems,
cobjects,comphook,verbose,globals,files,
symconst,symtable,types,aasm,scanner,
pass_1,hcodegen,temp_gen,cpubase,cpuasm
{$ifdef GDB}
,gdb
{$endif}
{$ifdef i386}
,tgeni386,cgai386
,cg386con,cg386mat,cg386cnv,cg386set,cg386add
,cg386mem,cg386cal,cg386ld,cg386flw,cg386inl
{$endif}
{$ifdef m68k}
,tgen68k,cga68k
,cg68kcon,cg68kmat,cg68kcnv,cg68kset,cg68kadd
,cg68kmem,cg68kcal,cg68kld,cg68kflw,cg68kinl
{$endif}
;
{*****************************************************************************
SecondPass
*****************************************************************************}
type
secondpassproc = procedure(var p : ptree);
procedure secondnothing(var p : ptree);
begin
end;
procedure seconderror(var p : ptree);
begin
p^.error:=true;
codegenerror:=true;
end;
procedure secondstatement(var p : ptree);
var
hp : ptree;
begin
hp:=p;
while assigned(hp) do
begin
if assigned(hp^.right) then
begin
cleartempgen;
{!!!!!!
oldrl:=temptoremove;
temptoremove:=new(plinkedlist,init);
}
secondpass(hp^.right);
{ !!!!!!!
some temporary data which can't be released elsewhere
removetemps(exprasmlist,temptoremove);
dispose(temptoremove,done);
temptoremove:=oldrl;
}
end;
hp:=hp^.left;
end;
end;
procedure secondblockn(var p : ptree);
begin
{ do second pass on left node }
if assigned(p^.left) then
secondpass(p^.left);
end;
procedure secondasm(var p : ptree);
var
hp,hp2 : pai;
localfixup,parafixup,
i : longint;
r : preference;
begin
if (pocall_inline in aktprocsym^.definition^.proccalloptions) then
begin
localfixup:=aktprocsym^.definition^.localst^.address_fixup;
parafixup:=aktprocsym^.definition^.parast^.address_fixup;
hp:=pai(p^.p_asm^.first);
while assigned(hp) do
begin
hp2:=pai(hp^.getcopy);
case hp2^.typ of
ait_instruction :
begin
{$ifdef i386}
{ fixup the references }
for i:=1 to paicpu(hp2)^.ops do
if paicpu(hp2)^.oper[i-1].typ=top_ref then
begin
r:=paicpu(hp2)^.oper[i-1].ref;
case r^.options of
ref_parafixup :
r^.offsetfixup:=parafixup;
ref_localfixup :
r^.offsetfixup:=localfixup;
end;
end;
exprasmlist^.concat(hp2);
{$endif i386}
end;
ait_marker :
begin
{ it's not an assembler block anymore }
if not(pai_marker(hp2)^.kind in [AsmBlockStart, AsmBlockEnd]) then
exprasmlist^.concat(hp2);
end;
else
exprasmlist^.concat(hp2);
end;
hp:=pai(hp^.next);
end
end
else
exprasmlist^.concatlist(p^.p_asm);
if not p^.object_preserved then
begin
{$ifdef i386}
maybe_loadesi;
{$endif}
{$ifdef m68k}
maybe_loada5;
{$endif}
end;
end;
procedure secondpass(var p : ptree);
const
procedures : array[ttreetyp] of secondpassproc =
(secondadd, {addn}
secondadd, {muln}
secondadd, {subn}
secondmoddiv, {divn}
secondadd, {symdifn}
secondmoddiv, {modn}
secondassignment, {assignn}
secondload, {loadn}
secondnothing, {range}
secondadd, {ltn}
secondadd, {lten}
secondadd, {gtn}
secondadd, {gten}
secondadd, {equaln}
secondadd, {unequaln}
secondin, {inn}
secondadd, {orn}
secondadd, {xorn}
secondshlshr, {shrn}
secondshlshr, {shln}
secondadd, {slashn}
secondadd, {andn}
secondsubscriptn, {subscriptn}
secondderef, {derefn}
secondaddr, {addrn}
seconddoubleaddr, {doubleaddrn}
secondordconst, {ordconstn}
secondtypeconv, {typeconvn}
secondcalln, {calln}
secondnothing, {callparan}
secondrealconst, {realconstn}
secondfixconst, {fixconstn}
secondumminus, {umminusn}
secondasm, {asmn}
secondvecn, {vecn}
secondpointerconst, {pointerconstn}
secondstringconst, {stringconstn}
secondfuncret, {funcretn}
secondselfn, {selfn}
secondnot, {notn}
secondinline, {inlinen}
secondniln, {niln}
seconderror, {errorn}
secondnothing, {typen}
secondhnewn, {hnewn}
secondhdisposen, {hdisposen}
secondnewn, {newn}
secondsimplenewdispose, {simpledisposen}
secondsetelement, {setelementn}
secondsetconst, {setconstn}
secondblockn, {blockn}
secondstatement, {statementn}
secondnothing, {loopn}
secondifn, {ifn}
secondbreakn, {breakn}
secondcontinuen, {continuen}
second_while_repeatn, {repeatn}
second_while_repeatn, {whilen}
secondfor, {forn}
secondexitn, {exitn}
secondwith, {withn}
secondcase, {casen}
secondlabel, {labeln}
secondgoto, {goton}
secondsimplenewdispose, {simplenewn}
secondtryexcept, {tryexceptn}
secondraise, {raisen}
secondnothing, {switchesn}
secondtryfinally, {tryfinallyn}
secondon, {onn}
secondis, {isn}
secondas, {asn}
seconderror, {caretn}
secondfail, {failn}
secondadd, {starstarn}
secondprocinline, {procinlinen}
secondarrayconstruct, {arrayconstructn}
secondnothing, {arrayconstructrangen}
secondnothing, {nothingn}
secondloadvmt {loadvmtn}
);
var
oldcodegenerror : boolean;
oldlocalswitches : tlocalswitches;
oldpos : tfileposinfo;
{$ifdef TEMPREGDEBUG}
prevp : pptree;
{$endif TEMPREGDEBUG}
begin
if not(p^.error) then
begin
oldcodegenerror:=codegenerror;
oldlocalswitches:=aktlocalswitches;
oldpos:=aktfilepos;
{$ifdef TEMPREGDEBUG}
testregisters32;
prevp:=curptree;
curptree:=@p;
p^.usableregs:=usablereg32;
{$endif TEMPREGDEBUG}
aktfilepos:=p^.fileinfo;
aktlocalswitches:=p^.localswitches;
codegenerror:=false;
procedures[p^.treetype](p);
p^.error:=codegenerror;
codegenerror:=codegenerror or oldcodegenerror;
aktlocalswitches:=oldlocalswitches;
aktfilepos:=oldpos;
{$ifdef TEMPREGDEBUG}
curptree:=prevp;
{$endif TEMPREGDEBUG}
{$ifdef EXTTEMPREGDEBUG}
if p^.usableregs-usablereg32>p^.reallyusedregs then
p^.reallyusedregs:=p^.usableregs-usablereg32;
if p^.reallyusedregs<p^.registers32 then
Comment(V_Debug,'registers32 overestimated '+tostr(p^.registers32)+
'>'+tostr(p^.reallyusedregs));
{$endif EXTTEMPREGDEBUG}
end
else
codegenerror:=true;
end;
function do_secondpass(var p : ptree) : boolean;
begin
codegenerror:=false;
if not(p^.error) then
secondpass(p);
do_secondpass:=codegenerror;
end;
var
{ the array ranges are oveestimated !!! }
{ max(maxvarregs,maxfpuvarregs) would be }
{ enough }
regvars : array[1..maxvarregs+maxfpuvarregs] of pvarsym;
regvars_para : array[1..maxvarregs+maxfpuvarregs] of boolean;
regvars_refs : array[1..maxvarregs+maxfpuvarregs] of longint;
parasym : boolean;
procedure searchregvars(p : pnamedindexobject);
var
i,j,k : longint;
begin
if (psym(p)^.typ=varsym) and (vo_regable in pvarsym(p)^.varoptions) then
begin
{ walk through all momentary register variables }
for i:=1 to maxvarregs do
begin
{ free register ? }
if regvars[i]=nil then
begin
regvars[i]:=pvarsym(p);
regvars_para[i]:=parasym;
break;
end;
{ else throw out a variable ? }
j:=pvarsym(p)^.refs;
{ parameter get a less value }
if parasym then
begin
if cs_littlesize in aktglobalswitches then
dec(j,1)
else
dec(j,100);
end;
if (j>regvars_refs[i]) and (j>0) then
begin
for k:=maxvarregs-1 downto i do
begin
regvars[k+1]:=regvars[k];
regvars_para[k+1]:=regvars_para[k];
end;
{ calc the new refs
pvarsym(p)^.refs:=j; }
regvars[i]:=pvarsym(p);
regvars_para[i]:=parasym;
regvars_refs[i]:=j;
break;
end;
end;
end;
end;
procedure searchfpuregvars(p : pnamedindexobject);
var
i,j,k : longint;
begin
if (psym(p)^.typ=varsym) and (vo_fpuregable in pvarsym(p)^.varoptions) then
begin
{ walk through all momentary register variables }
for i:=1 to maxfpuvarregs do
begin
{ free register ? }
if regvars[i]=nil then
begin
regvars[i]:=pvarsym(p);
regvars_para[i]:=parasym;
break;
end;
{ else throw out a variable ? }
j:=pvarsym(p)^.refs;
{ parameter get a less value }
if parasym then
begin
if cs_littlesize in aktglobalswitches then
dec(j,1)
else
dec(j,100);
end;
if (j>regvars_refs[i]) and (j>0) then
begin
for k:=maxfpuvarregs-1 downto i do
begin
regvars[k+1]:=regvars[k];
regvars_para[k+1]:=regvars_para[k];
end;
{ calc the new refs
pvarsym(p)^.refs:=j; }
regvars[i]:=pvarsym(p);
regvars_para[i]:=parasym;
regvars_refs[i]:=j;
break;
end;
end;
end;
end;
procedure generatecode(var p : ptree);
var
i : longint;
regsize : topsize;
hr : preference;
label
nextreg;
begin
{!!!!!!!! temptoremove:=nil; }
cleartempgen;
{ when size optimization only count occurrence }
if cs_littlesize in aktglobalswitches then
t_times:=1
else
{ reference for repetition is 100 }
t_times:=100;
{ clear register count }
clearregistercount;
use_esp_stackframe:=false;
if not(do_firstpass(p)) then
begin
{ max. optimizations }
{ only if no asm is used }
{ and no try statement }
if (cs_regalloc in aktglobalswitches) and
((procinfo^.flags and (pi_uses_asm or pi_uses_exceptions))=0) then
begin
{ can we omit the stack frame ? }
{ conditions:
1. procedure (not main block)
2. no constructor or destructor
3. no call to other procedures
4. no interrupt handler
}
{!!!!!! this doesn work yet, because of problems with
with linux and windows
}
(*
if assigned(aktprocsym) then
begin
if not(assigned(procinfo^._class)) and
not(aktprocsym^.definition^.proctypeoption in [potype_constructor,potype_destructor]) and
not(po_interrupt in aktprocsym^.definition^.procoptions) and
((procinfo^.flags and pi_do_call)=0) and
(lexlevel>=normal_function_level) then
begin
{ use ESP as frame pointer }
procinfo^.framepointer:=stack_pointer;
use_esp_stackframe:=true;
{ calc parameter distance new }
dec(procinfo^.framepointer_offset,4);
dec(procinfo^.ESI_offset,4);
{ is this correct ???}
{ retoffset can be negativ for results in eax !! }
{ the value should be decreased only if positive }
if procinfo^.retoffset>=0 then
dec(procinfo^.retoffset,4);
dec(procinfo^.call_offset,4);
aktprocsym^.definition^.parast^.address_fixup:=procinfo^.call_offset;
end;
end;
*)
{ $ifdef dummy}
if (p^.registers32<4) then
begin
for i:=1 to maxvarregs do
regvars[i]:=nil;
parasym:=false;
symtablestack^.foreach({$ifndef TP}@{$endif}searchregvars);
{ copy parameter into a register ? }
parasym:=true;
symtablestack^.next^.foreach({$ifndef TP}@{$endif}searchregvars);
{ hold needed registers free }
for i:=maxvarregs downto maxvarregs-p^.registers32+1 do
regvars[i]:=nil;
{ now assign register }
for i:=1 to maxvarregs-p^.registers32 do
begin
if assigned(regvars[i]) then
begin
{ it is nonsens, to copy the variable to }
{ a register because we need then much }
{ too pushes ? }
if reg_pushes[varregs[i]]>=regvars[i]^.refs then
begin
regvars[i]:=nil;
goto nextreg;
end;
{ register is no longer available for }
{ expressions }
{ search the register which is the most }
{ unused }
usableregs:=usableregs-[varregs[i]];
{$ifdef i386}
procinfo^.aktentrycode^.concat(new(pairegalloc,alloc(varregs[i])));
{$endif i386}
is_reg_var[varregs[i]]:=true;
dec(c_usableregs);
{ possibly no 32 bit register are needed }
{ call by reference/const ? }
if (regvars[i]^.varspez=vs_var) or
((regvars[i]^.varspez=vs_const) and
push_addr_param(regvars[i]^.definition)) then
begin
regvars[i]^.reg:=varregs[i];
regsize:=S_L;
end
else
if (regvars[i]^.definition^.deftype=orddef) and
(porddef(regvars[i]^.definition)^.size=1) then
begin
{$ifdef i386}
regvars[i]^.reg:=reg32toreg8(varregs[i]);
{$endif}
regsize:=S_B;
end
else
if (regvars[i]^.definition^.deftype=orddef) and
(porddef(regvars[i]^.definition)^.size=2) then
begin
{$ifdef i386}
regvars[i]^.reg:=reg32toreg16(varregs[i]);
{$endif}
regsize:=S_W;
end
else
begin
regvars[i]^.reg:=varregs[i];
regsize:=S_L;
end;
{ parameter must be load }
if regvars_para[i] then
begin
{ procinfo is there actual, }
{ because we can't never be in a }
{ nested procedure }
{ when loading parameter to reg }
new(hr);
reset_reference(hr^);
hr^.offset:=pvarsym(regvars[i])^.address+procinfo^.call_offset;
hr^.base:=procinfo^.framepointer;
{$ifdef i386}
procinfo^.aktentrycode^.concat(new(paicpu,op_ref_reg(A_MOV,regsize,
hr,regvars[i]^.reg)));
{$endif i386}
{$ifdef m68k}
procinfo^.aktentrycode^.concat(new(paicpu,op_ref_reg(A_MOVE,regsize,
hr,regvars[i]^.reg)));
{$endif m68k}
unused:=unused - [regvars[i]^.reg];
end;
{ procedure uses this register }
{$ifdef i386}
usedinproc:=usedinproc or ($80 shr byte(varregs[i]));
{$endif i386}
{$ifdef m68k}
usedinproc:=usedinproc or ($800 shr word(varregs[i]));
{$endif m68k}
end;
nextreg:
{ dummy }
regsize:=S_W;
end;
for i:=1 to maxvarregs do
begin
if assigned(regvars[i]) then
begin
if cs_asm_source in aktglobalswitches then
procinfo^.aktentrycode^.insert(new(pai_asm_comment,init(strpnew(regvars[i]^.name+
' with weight '+tostr(regvars[i]^.refs)+' assigned to register '+
reg2str(regvars[i]^.reg)))));
if (status.verbosity and v_debug)=v_debug then
Message3(cg_d_register_weight,reg2str(regvars[i]^.reg),
tostr(regvars[i]^.refs),regvars[i]^.name);
end;
end;
end;
{ $endif dummy}
if ((p^.registersfpu+1)<maxfpuvarregs) then
begin
for i:=1 to maxfpuvarregs do
regvars[i]:=nil;
parasym:=false;
symtablestack^.foreach({$ifndef TP}@{$endif}searchfpuregvars);
{$ifdef dummy}
{ copy parameter into a register ? }
parasym:=true;
symtablestack^.next^.foreach({$ifndef TP}@{$endif}searchregvars);
{$endif dummy}
{ hold needed registers free }
{ in non leaf procedures we must be very careful }
{ with assigning registers }
if (procinfo^.flags and pi_do_call)<>0 then
begin
for i:=maxfpuvarregs downto 2 do
regvars[i]:=nil;
end
else
begin
for i:=maxfpuvarregs downto maxfpuvarregs-p^.registersfpu do
regvars[i]:=nil;
end;
{ now assign register }
for i:=1 to maxfpuvarregs do
begin
if assigned(regvars[i]) then
begin
{$ifdef i386}
{ reserve place on the FPU stack }
regvars[i]^.reg:=correct_fpuregister(R_ST0,i-1);
procinfo^.aktentrycode^.concat(new(paicpu,op_none(A_FLDZ,S_NO)));
{ ... and clean it up }
procinfo^.aktexitcode^.concat(new(paicpu,op_reg(A_FSTP,S_NO,R_ST0)));
{$endif i386}
{$ifdef m68k}
regvars[i]^.reg:=fpuvarregs[i];
{$endif m68k}
{$ifdef dummy}
{ parameter must be load }
if regvars_para[i] then
begin
{ procinfo is there actual, }
{ because we can't never be in a }
{ nested procedure }
{ when loading parameter to reg }
new(hr);
reset_reference(hr^);
hr^.offset:=pvarsym(regvars[i])^.address+procinfo^.call_offset;
hr^.base:=procinfo^.framepointer;
{$ifdef i386}
procinfo^.aktentrycode^.concat(new(paicpu,op_ref_reg(A_MOV,regsize,
hr,regvars[i]^.reg)));
{$endif i386}
{$ifdef m68k}
procinfo^.aktentrycode^.concat(new(paicpu,op_ref_reg(A_MOVE,regsize,
hr,regvars[i]^.reg)));
{$endif m68k}
end;
{$endif dummy}
end;
end;
if cs_asm_source in aktglobalswitches then
procinfo^.aktentrycode^.insert(new(pai_asm_comment,init(strpnew(tostr(p^.registersfpu)+
' registers on FPU stack used by temp. expressions'))));
for i:=1 to maxfpuvarregs do
begin
if assigned(regvars[i]) then
begin
if cs_asm_source in aktglobalswitches then
procinfo^.aktentrycode^.insert(new(pai_asm_comment,init(strpnew(regvars[i]^.name+
' with weight '+tostr(regvars[i]^.refs)+' assigned to register '+
reg2str(regvars[i]^.reg)))));
if (status.verbosity and v_debug)=v_debug then
Message3(cg_d_register_weight,reg2str(regvars[i]^.reg),
tostr(regvars[i]^.refs),regvars[i]^.name);
end;
end;
if cs_asm_source in aktglobalswitches then
procinfo^.aktentrycode^.insert(new(pai_asm_comment,init(strpnew('Register variable assignment:'))));
end;
end;
if assigned(aktprocsym) and
(pocall_inline in aktprocsym^.definition^.proccalloptions) then
make_const_global:=true;
do_secondpass(p);
if assigned(procinfo^.def) then
procinfo^.def^.fpu_used:=p^.registersfpu;
{ all registers can be used again }
resetusableregisters;
end;
procinfo^.aktproccode^.concatlist(exprasmlist);
make_const_global:=false;
end;
end.
{
$Log$
Revision 1.41 1999-11-06 14:34:21 peter
* truncated log to 20 revs
Revision 1.40 1999/09/27 23:44:52 peter
* procinfo is now a pointer
* support for result setting in sub procedure
Revision 1.39 1999/09/26 21:30:17 peter
+ constant pointer support which can happend with typecasting like
const p=pointer(1)
* better procvar parsing in typed consts
Revision 1.38 1999/09/16 23:05:54 florian
* m68k compiler is again compilable (only gas writer, no assembler reader)
Revision 1.37 1999/09/15 20:35:41 florian
* small fix to operator overloading when in MMX mode
+ the compiler uses now fldz and fld1 if possible
+ some fixes to floating point registers
+ some math. functions (arctan, ln, sin, cos, sqrt, sqr, pi) are now inlined
* .... ???
Revision 1.36 1999/09/07 14:12:35 jonas
* framepointer cannot be changed to esp for methods
Revision 1.35 1999/08/27 10:46:26 pierre
+ some EXTTEMPREGDEBUG code added
Revision 1.34 1999/08/25 12:00:01 jonas
* changed pai386, paippc and paiapha (same for tai*) to paicpu (taicpu)
Revision 1.33 1999/08/24 09:07:04 pierre
* wrong testregisters32 placement corrected
Revision 1.32 1999/08/23 23:25:59 pierre
+ TEMPREGDEBUG code, test of register allocation
if a tree uses more than registers32 regs then
internalerror(10) is issued
+ EXTTEMPREGDEBUG will also give internalerror(10) if
a same register is freed twice (happens in several part
of current compiler like addn for strings and sets)
Revision 1.31 1999/08/07 14:20:59 florian
* some small problems fixed
Revision 1.30 1999/08/04 14:21:07 florian
* now every available fpu register is used for
fpu register variables
Revision 1.29 1999/08/04 13:45:28 florian
+ floating point register variables !!
* pairegalloc is now generated for register variables
Revision 1.28 1999/08/04 00:23:10 florian
* renamed i386asm and i386base to cpuasm and cpubase
Revision 1.27 1999/08/03 22:02:55 peter
* moved bitmask constants to sets
* some other type/const renamings
Revision 1.26 1999/06/02 22:44:08 pierre
* previous wrong log corrected
Revision 1.25 1999/06/02 22:25:41 pierre
* changed $ifdef FPC @ into $ifndef TP
Revision 1.24 1999/06/01 14:45:50 peter
* @procvar is now always needed for FPC
Revision 1.23 1999/05/27 19:44:43 peter
* removed oldasm
* plabel -> pasmlabel
* -a switches to source writing automaticly
* assembler readers OOPed
* asmsymbol automaticly external
* jumptables and other label fixes for asm readers
Revision 1.22 1999/05/18 14:15:50 peter
* containsself fixes
* checktypes()
Revision 1.21 1999/05/17 21:57:11 florian
* new temporary ansistring handling
}