fpc/compiler/i8086/cpupara.pas
2021-11-17 22:19:57 +01:00

818 lines
32 KiB
ObjectPascal

{
Copyright (c) 2002 by Florian Klaempfl
Generates the argument location information for i8086
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 cpupara;
{$i fpcdefs.inc}
interface
uses
globtype,
aasmtai,aasmdata,cpubase,cgbase,cgutils,
symconst,symtype,symsym,symdef,
parabase,paramgr;
type
tcpuparamanager = class(tparamanager)
function param_use_paraloc(const cgpara:tcgpara):boolean;override;
function ret_in_param(def:tdef;pd:tabstractprocdef):boolean;override;
function asm_result_var(def:tdef;pd:tabstractprocdef):boolean;override;
function push_addr_param(varspez:tvarspez;def : tdef;calloption : tproccalloption) : boolean;override;
function get_para_align(calloption : tproccalloption):byte;override;
function get_volatile_registers_int(calloption : tproccalloption):tcpuregisterset;override;
function get_volatile_registers_fpu(calloption : tproccalloption):tcpuregisterset;override;
function get_volatile_registers_mm(calloption : tproccalloption):tcpuregisterset;override;
function get_saved_registers_int(calloption : tproccalloption):tcpuregisterarray;override;
{ Returns the location for the nr-st 16 Bit int parameter
if every parameter before is an 16 Bit int parameter as well
and if the calling conventions for the helper routines of the
rtl are used.
TODO: This allocates 32-bit ints on other CPU architectures. Since
we're small/tiny model only, for now we can get away with allocating
always 16-bit int parameters, but in the future, when we implement
other memory models, this mechanism has to be extended somehow to
support 32-bit addresses on a 16-bit CPU.
}
procedure getcgtempparaloc(list: TAsmList; pd : tabstractprocdef; nr : longint; var cgpara : tcgpara);override;
function create_paraloc_info(p : tabstractprocdef; side: tcallercallee):longint;override;
function create_varargs_paraloc_info(p : tabstractprocdef; side: tcallercallee; varargspara:tvarargsparalist):longint;override;
procedure createtempparaloc(list: TAsmList;calloption : tproccalloption;parasym : tparavarsym;can_use_final_stack_loc : boolean;var cgpara:TCGPara);override;
function get_funcretloc(p : tabstractprocdef; side: tcallercallee; forcetempdef: tdef): TCGPara;override;
private
procedure create_stdcall_paraloc_info(p : tabstractprocdef; side: tcallercallee;paras:tparalist;var parasize:longint);
procedure create_register_paraloc_info(p : tabstractprocdef; side: tcallercallee;paras:tparalist;var parareg,parasize:longint);
end;
implementation
uses
cutils,
systems,verbose,
symtable,symcpu,
globals,defutil;
const
parasupregs : array[0..2] of tsuperregister = (RS_AX,RS_DX,RS_BX);
{****************************************************************************
tcpuparamanager
****************************************************************************}
function tcpuparamanager.param_use_paraloc(const cgpara:tcgpara):boolean;
var
paraloc : pcgparalocation;
begin
if not assigned(cgpara.location) then
internalerror(200410102);
result:=true;
{ All locations are LOC_REFERENCE }
paraloc:=cgpara.location;
while assigned(paraloc) do
begin
if (paraloc^.loc<>LOC_REFERENCE) then
begin
result:=false;
exit;
end;
paraloc:=paraloc^.next;
end;
end;
function tcpuparamanager.ret_in_param(def:tdef;pd:tabstractprocdef):boolean;
begin
if handle_common_ret_in_param(def,pd,result) then
exit;
if (def.size > 8) and (def.typ <> floatdef) then
begin
result:=true;
exit;
end;
result:=inherited ret_in_param(def,pd);
end;
function tcpuparamanager.asm_result_var(def:tdef;pd:tabstractprocdef):boolean;
begin
if not(po_assembler in pd.procoptions) then
internalerror(2018021502);
result:=ret_in_param(def,pd);
end;
function tcpuparamanager.push_addr_param(varspez:tvarspez;def : tdef;calloption : tproccalloption) : boolean;
begin
result:=false;
{ var,out,constref always require address }
if varspez in [vs_var,vs_out,vs_constref] then
begin
result:=true;
exit;
end;
{ Only vs_const, vs_value here }
case def.typ of
variantdef :
begin
{ variants are small enough to be passed by value except if
required by the windows api
variants are somethings very delphi/windows specific so do it like
windows/delphi (FK)
}
if ((target_info.system=system_i386_win32) and
(calloption in [pocall_stdcall,pocall_safecall]) and
(varspez=vs_const)) or
(calloption=pocall_register) then
result:=true
else
result:=false;
end;
formaldef :
result:=true;
recorddef :
begin
{ Delphi stdcall passes records on the stack for call by value }
if (target_info.system=system_i386_win32) and
(calloption=pocall_stdcall) and
(varspez=vs_value) then
result:=false
else
result:=
(not(calloption in (cdecl_pocalls)) and
(def.size>sizeof(aint)));
end;
arraydef :
begin
{ array of const values are pushed on the stack as
well as dyn. arrays }
if (calloption in cdecl_pocalls) then
result:=not(is_array_of_const(def) or
is_dynamic_array(def))
else
begin
result:=(
(tarraydef(def).highrange>=tarraydef(def).lowrange) and
(def.size>sizeof(aint))
) or
is_open_array(def) or
is_array_of_const(def) or
is_array_constructor(def);
end;
end;
objectdef :
result:=is_object(def);
stringdef :
result:= (tstringdef(def).stringtype in [st_shortstring,st_longstring]);
procvardef :
result:=not(calloption in cdecl_pocalls) and not tprocvardef(def).is_addressonly;
setdef :
result:=not(calloption in cdecl_pocalls) and (not is_smallset(def));
else
;
end;
end;
function tcpuparamanager.get_para_align(calloption : tproccalloption):byte;
begin
result:=std_param_align;
end;
function tcpuparamanager.get_volatile_registers_int(calloption : tproccalloption):tcpuregisterset;
begin
case calloption of
pocall_internproc :
result:=[];
pocall_register,
pocall_cdecl:
result:=[RS_AX,RS_DX,RS_CX,RS_BX];
pocall_safecall,
pocall_stdcall,
pocall_cppdecl,
pocall_pascal :
result:=[RS_AX,RS_DX,RS_CX,RS_SI,RS_DI,RS_BX];
else
internalerror(200309071);
end;
end;
function tcpuparamanager.get_volatile_registers_fpu(calloption : tproccalloption):tcpuregisterset;
begin
result:=[0..first_fpu_imreg-1];
end;
function tcpuparamanager.get_volatile_registers_mm(calloption : tproccalloption):tcpuregisterset;
begin
result:=[0..first_mm_imreg-1];
end;
function tcpuparamanager.get_saved_registers_int(calloption : tproccalloption):tcpuregisterarray;
const
saveregs_cdecl: tcpuregisterarray = (RS_BP,RS_SI,RS_DI);
saveregs_pascal: tcpuregisterarray = (RS_BP);
begin
case calloption of
pocall_register,
pocall_cdecl:
result:=saveregs_cdecl;
pocall_internproc,
pocall_safecall,
pocall_stdcall,
pocall_cppdecl,
pocall_pascal :
result:=saveregs_pascal;
else
internalerror(2018042301);
end;
end;
procedure tcpuparamanager.getcgtempparaloc(list: TAsmList; pd : tabstractprocdef; nr : longint; var cgpara : tcgpara);
var
paraloc : pcgparalocation;
psym: tparavarsym;
pdef : tdef;
begin
psym:=tparavarsym(pd.paras[nr-1]);
pdef:=psym.vardef;
if push_addr_param(psym.varspez,pdef,pd.proccalloption) then
pdef:=cpointerdef.getreusable_no_free(pdef);
cgpara.reset;
cgpara.size:=def_cgsize(pdef);
cgpara.intsize:=tcgsize2size[cgpara.size];
cgpara.alignment:=get_para_align(pd.proccalloption);
cgpara.def:=pdef;
paraloc:=cgpara.add_location;
with paraloc^ do
begin
size:=def_cgsize(pdef);
def:=pdef;
if pd.proccalloption=pocall_register then
begin
if (nr<=length(parasupregs)) then
begin
if nr=0 then
internalerror(200309271);
loc:=LOC_REGISTER;
register:=newreg(R_INTREGISTER,parasupregs[nr-1],R_SUBWHOLE);
end
else
begin
loc:=LOC_REFERENCE;
reference.index:=NR_STACK_POINTER_REG;
{ the previous parameters didn't take up room in memory }
reference.offset:=sizeof(aint)*(nr-length(parasupregs)-1)
end;
end
else
begin
loc:=LOC_REFERENCE;
reference.index:=NR_STACK_POINTER_REG;
reference.offset:=sizeof(aint)*nr;
end;
end;
end;
function tcpuparamanager.get_funcretloc(p : tabstractprocdef; side: tcallercallee; forcetempdef: tdef): TCGPara;
var
retcgsize : tcgsize;
paraloc : pcgparalocation;
usedef: tdef;
handled: boolean;
begin
if not assigned(forcetempdef) then
usedef:=p.returndef
else
usedef:=forcetempdef;
handled:=set_common_funcretloc_info(p,usedef,retcgsize,result);
{ normally forcetempdef is passed straight through to
set_common_funcretloc_info and that one will correctly determine whether
the location is a temporary one, but that doesn't work here because we
sometimes have to change the type }
result.temporary:=assigned(forcetempdef);
if handled then
exit;
{ Return in FPU register? }
if result.def.typ=floatdef then
begin
paraloc:=result.add_location;
paraloc^.loc:=LOC_FPUREGISTER;
paraloc^.register:=NR_FPU_RESULT_REG;
paraloc^.size:=retcgsize;
paraloc^.def:=result.def;
end
else
{ Return in register }
begin
paraloc:=result.add_location;
paraloc^.loc:=LOC_REGISTER;
if retcgsize in [OS_64,OS_S64] then
begin
{ bits 0..15 }
if side=callerside then
paraloc^.register:=NR_FUNCTION_RESULT64_LOW_REG
else
paraloc^.register:=NR_FUNCTION_RETURN64_LOW_REG;
paraloc^.size:=OS_16;
paraloc^.def:=u16inttype;
{ bits 16..31 }
paraloc:=result.add_location;
paraloc^.loc:=LOC_REGISTER;
if side=callerside then
paraloc^.register:=NR_FUNCTION_RESULT64_HIGH_REG
else
paraloc^.register:=NR_FUNCTION_RETURN64_HIGH_REG;
paraloc^.size:=OS_16;
paraloc^.def:=u16inttype;
{ bits 32..47 }
paraloc:=result.add_location;
paraloc^.loc:=LOC_REGISTER;
if side=callerside then
paraloc^.register:=NR_FUNCTION_RESULT64_HIGHER_REG
else
paraloc^.register:=NR_FUNCTION_RETURN64_HIGHER_REG;
paraloc^.size:=OS_16;
paraloc^.def:=u16inttype;
{ bits 48..63 }
paraloc:=result.add_location;
paraloc^.loc:=LOC_REGISTER;
if side=callerside then
paraloc^.register:=NR_FUNCTION_RESULT64_HIGHEST_REG
else
paraloc^.register:=NR_FUNCTION_RETURN64_HIGHEST_REG;
paraloc^.size:=OS_16;
paraloc^.def:=u16inttype;
end
else if retcgsize in [OS_32,OS_S32] then
begin
{ low 16bits }
if side=callerside then
paraloc^.register:=NR_FUNCTION_RESULT32_LOW_REG
else
paraloc^.register:=NR_FUNCTION_RETURN32_LOW_REG;
paraloc^.size:=OS_16;
paraloc^.def:=u16inttype;
{ high 16bits }
paraloc:=result.add_location;
paraloc^.loc:=LOC_REGISTER;
if side=callerside then
paraloc^.register:=NR_FUNCTION_RESULT32_HIGH_REG
else
paraloc^.register:=NR_FUNCTION_RETURN32_HIGH_REG;
paraloc^.size:=OS_16;
paraloc^.def:=u16inttype;
end
else
begin
paraloc^.size:=retcgsize;
paraloc^.def:=result.def;
if side=callerside then
paraloc^.register:=newreg(R_INTREGISTER,RS_FUNCTION_RESULT_REG,cgsize2subreg(R_INTREGISTER,retcgsize))
else
paraloc^.register:=newreg(R_INTREGISTER,RS_FUNCTION_RETURN_REG,cgsize2subreg(R_INTREGISTER,retcgsize));
end;
end;
end;
procedure tcpuparamanager.create_stdcall_paraloc_info(p : tabstractprocdef; side: tcallercallee;paras:tparalist;var parasize:longint);
var
i : integer;
hp : tparavarsym;
paradef : tdef;
paraloc : pcgparalocation;
l,
paralen,
varalign : longint;
paraalign : shortint;
paracgsize : tcgsize;
firstparaloc,
pushaddr : boolean;
pushleftright: boolean;
begin
paraalign:=get_para_align(p.proccalloption);
{ interrupt routines need parameter fixup }
if po_interrupt in p.procoptions then
if is_proc_far(p) then
dec(parasize,6)
else
dec(parasize,4);
{ Offset is calculated like:
sub esp,12
mov [esp+8],para3
mov [esp+4],para2
mov [esp],para1
call function
That means for pushes the para with the
highest offset (see para3) needs to be pushed first
}
pushleftright:=(p.proccalloption in pushleftright_pocalls) or (po_interrupt in p.procoptions);
if pushleftright then
i:=paras.count-1
else
i:=0;
while (pushleftright and (i>=0)) or
(not(pushleftright) and (i<=paras.count-1)) do
begin
hp:=tparavarsym(paras[i]);
paradef:=hp.vardef;
pushaddr:=push_addr_param(hp.varspez,paradef,p.proccalloption);
if pushaddr then
begin
paralen:=voidpointertype.size;
paracgsize:=int_cgsize(voidpointertype.size);
paradef:=cpointerdef.getreusable_no_free(paradef);
end
else
begin
paralen:=push_size(hp.varspez,paradef,p.proccalloption);
paracgsize:=def_cgsize(paradef);
end;
hp.paraloc[side].reset;
hp.paraloc[side].size:=paracgsize;
hp.paraloc[side].intsize:=paralen;
hp.paraloc[side].def:=paradef;
hp.paraloc[side].Alignment:=paraalign;
{ Copy to stack? }
if (paracgsize=OS_NO) or
(use_fixed_stack) then
begin
paraloc:=hp.paraloc[side].add_location;
paraloc^.loc:=LOC_REFERENCE;
paraloc^.size:=paracgsize;
paraloc^.def:=paradef;
if side=callerside then
paraloc^.reference.index:=NR_STACK_POINTER_REG
else
paraloc^.reference.index:=NR_FRAME_POINTER_REG;
varalign:=used_align(size_2_align(paralen),paraalign,paraalign);
paraloc^.reference.offset:=parasize;
if side=calleeside then
begin
inc(paraloc^.reference.offset,target_info.first_parm_offset);
if is_proc_far(p) then
inc(paraloc^.reference.offset,2);
end;
parasize:=align(parasize+paralen,varalign);
end
else
begin
if paralen=0 then
internalerror(2005011604);
firstparaloc:=true;
while (paralen>0) do
begin
paraloc:=hp.paraloc[side].add_location;
paraloc^.loc:=LOC_REFERENCE;
{ single and double need a single location }
if (paracgsize in [OS_F64,OS_F32]) then
begin
paraloc^.size:=paracgsize;
paraloc^.def:=paradef;
l:=paralen;
end
else
begin
{ We can allocate at maximum 16 bits per location }
if paralen>=sizeof(aint) then
begin
l:=sizeof(aint);
paraloc^.def:=uinttype;
end
else
begin
l:=paralen;
paraloc^.def:=get_paraloc_def(paradef,l,firstparaloc);
end;
paraloc^.size:=int_cgsize(l);
end;
if (side=callerside) or
(po_nostackframe in p.procoptions) then
paraloc^.reference.index:=NR_STACK_POINTER_REG
else
paraloc^.reference.index:=NR_FRAME_POINTER_REG;
varalign:=used_align(size_2_align(l),paraalign,paraalign);
paraloc^.reference.offset:=parasize;
if side=calleeside then
begin
if not(po_nostackframe in p.procoptions) then
inc(paraloc^.reference.offset,target_info.first_parm_offset)
else
{ return addres }
inc(paraloc^.reference.offset,2);
if is_proc_far(p) then
inc(paraloc^.reference.offset,2);
end;
parasize:=align(parasize+l,varalign);
dec(paralen,l);
firstparaloc:=false;
end;
end;
if pushleftright then
dec(i)
else
inc(i);
end;
end;
procedure tcpuparamanager.create_register_paraloc_info(p : tabstractprocdef; side: tcallercallee;paras:tparalist;
var parareg,parasize:longint);
var
hp : tparavarsym;
paradef : tdef;
paraloc : pcgparalocation;
paracgsize : tcgsize;
i : integer;
l,
paralen,
varalign : longint;
pushaddr : boolean;
paraalign : shortint;
pass : byte;
firstparaloc : boolean;
begin
if paras.count=0 then
exit;
paraalign:=get_para_align(p.proccalloption);
{ clean up here so we can later detect properly if a parameter has been
assigned or not
}
for i:=0 to paras.count-1 do
tparavarsym(paras[i]).paraloc[side].reset;
{ Register parameters are assigned from left to right,
stack parameters from right to left so assign first the
register parameters in a first pass, in the second
pass all unhandled parameters are done }
for pass:=1 to 2 do
begin
if pass=1 then
i:=0
else
i:=paras.count-1;
while true do
begin
hp:=tparavarsym(paras[i]);
paradef:=hp.vardef;
if not(assigned(hp.paraloc[side].location)) then
begin
pushaddr:=push_addr_param(hp.varspez,hp.vardef,p.proccalloption);
if pushaddr then
begin
paralen:=voidpointertype.size;
paracgsize:=int_cgsize(voidpointertype.size);
paradef:=cpointerdef.getreusable_no_free(paradef);
end
else
begin
paralen:=push_size(hp.varspez,hp.vardef,p.proccalloption);
paracgsize:=def_cgsize(hp.vardef);
end;
hp.paraloc[side].size:=paracgsize;
hp.paraloc[side].intsize:=paralen;
hp.paraloc[side].Alignment:=paraalign;
hp.paraloc[side].def:=paradef;
{
AX
DX
BX
Stack
Stack
32/64bit values,far pointers,floats,arrays and records are
always on the stack. The only exception is that Longints
(but not far pointers) can be passed in DX:AX if these
registers are unallocated.
In case of po_delphi_nested_cc, the parent frame pointer
is also always passed on the stack.
}
if (parareg=low(parasupregs)) and
(paralen=4) and
(hp.vardef.typ=orddef) then
begin
if pass=1 then
begin
paraloc:=hp.paraloc[side].add_location;
paraloc^.size:=OS_16;
paraloc^.def:=paradef;
paraloc^.loc:=LOC_REGISTER;
paraloc^.register:=newreg(R_INTREGISTER,parasupregs[parareg],R_SUBW);
inc(parareg);
paraloc:=hp.paraloc[side].add_location;
paraloc^.size:=OS_16;
paraloc^.def:=paradef;
paraloc^.loc:=LOC_REGISTER;
paraloc^.register:=newreg(R_INTREGISTER,parasupregs[parareg],R_SUBW);
inc(parareg);
end;
end
else if (parareg<=high(parasupregs)) and
(paralen<=sizeof(aint)) and
(not(hp.vardef.typ in [floatdef,recorddef,arraydef]) or
pushaddr or
is_dynamic_array(hp.vardef)) and
(not(vo_is_parentfp in hp.varoptions) or
not(po_delphi_nested_cc in p.procoptions)) then
begin
if pass=1 then
begin
paraloc:=hp.paraloc[side].add_location;
paraloc^.size:=paracgsize;
paraloc^.def:=paradef;
paraloc^.loc:=LOC_REGISTER;
paraloc^.register:=newreg(R_INTREGISTER,parasupregs[parareg],cgsize2subreg(R_INTREGISTER,paracgsize));
inc(parareg);
end;
end
else
if pass=2 then
begin
{ Copy to stack? }
if (use_fixed_stack) or
(paracgsize=OS_NO) then
begin
paraloc:=hp.paraloc[side].add_location;
paraloc^.loc:=LOC_REFERENCE;
paraloc^.size:=paracgsize;
paraloc^.def:=paradef;
if side=callerside then
paraloc^.reference.index:=NR_STACK_POINTER_REG
else
paraloc^.reference.index:=NR_FRAME_POINTER_REG;
varalign:=used_align(size_2_align(paralen),paraalign,paraalign);
paraloc^.reference.offset:=parasize;
if side=calleeside then
begin
inc(paraloc^.reference.offset,target_info.first_parm_offset);
if is_proc_far(p) then
inc(paraloc^.reference.offset,2);
end;
parasize:=align(parasize+paralen,varalign);
end
else
begin
if paralen=0 then
internalerror(2005011605);
firstparaloc:=true;
while (paralen>0) do
begin
paraloc:=hp.paraloc[side].add_location;
paraloc^.loc:=LOC_REFERENCE;
{ Extended and double need a single location }
if (paracgsize in [OS_F64,OS_F32]) then
begin
paraloc^.size:=paracgsize;
paraloc^.def:=paradef;
l:=paralen;
end
else
begin
{ We can allocate at maximum 16 bits per location }
if paralen>=sizeof(aint) then
begin
l:=sizeof(aint);
paraloc^.def:=uinttype;
end
else
begin
l:=paralen;
paraloc^.def:=get_paraloc_def(paradef,l,firstparaloc);
end;
paraloc^.size:=int_cgsize(l);
end;
if side=callerside then
paraloc^.reference.index:=NR_STACK_POINTER_REG
else
paraloc^.reference.index:=NR_FRAME_POINTER_REG;
varalign:=used_align(size_2_align(l),paraalign,paraalign);
paraloc^.reference.offset:=parasize;
if side=calleeside then
begin
inc(paraloc^.reference.offset,target_info.first_parm_offset);
if is_proc_far(p) then
inc(paraloc^.reference.offset,2);
end;
parasize:=align(parasize+l,varalign);
dec(paralen,l);
firstparaloc:=false;
end;
end;
end;
end;
case pass of
1:
begin
if i=paras.count-1 then
break;
inc(i);
end;
2:
begin
if i=0 then
break;
dec(i);
end;
end;
end;
end;
end;
function tcpuparamanager.create_paraloc_info(p : tabstractprocdef; side: tcallercallee):longint;
var
parasize,
parareg : longint;
begin
parasize:=0;
parareg:=0;
case p.proccalloption of
pocall_register :
create_register_paraloc_info(p,side,p.paras,parareg,parasize);
pocall_internproc :
begin
{ Use default calling }
{$warnings off}
if (pocall_default=pocall_register) then
create_register_paraloc_info(p,side,p.paras,parareg,parasize)
else
create_stdcall_paraloc_info(p,side,p.paras,parasize);
{$warnings on}
end;
else
create_stdcall_paraloc_info(p,side,p.paras,parasize);
end;
create_funcretloc_info(p,side);
result:=parasize;
end;
function tcpuparamanager.create_varargs_paraloc_info(p : tabstractprocdef; side: tcallercallee; varargspara:tvarargsparalist):longint;
var
parasize : longint;
begin
parasize:=0;
{ calculate the registers for the normal parameters }
create_stdcall_paraloc_info(p,side,p.paras,parasize);
{ append the varargs }
if assigned(varargspara) then
begin
if side=callerside then
create_stdcall_paraloc_info(p,side,varargspara,parasize)
else
internalerror(2019021925);
end;
create_funcretloc_info(p,side);
result:=parasize;
end;
procedure tcpuparamanager.createtempparaloc(list: TAsmList;calloption : tproccalloption;parasym : tparavarsym;can_use_final_stack_loc : boolean;var cgpara:TCGPara);
begin
{ Never a need for temps when value is pushed (calls inside parameters
will simply allocate even more stack space for their parameters) }
if not(use_fixed_stack) then
can_use_final_stack_loc:=true;
inherited createtempparaloc(list,calloption,parasym,can_use_final_stack_loc,cgpara);
end;
begin
paramanager:=tcpuparamanager.create;
end.