fpc/compiler/rgobj.pas

2400 lines
79 KiB
ObjectPascal

{
$Id$
Copyright (c) 1998-2002 by Florian Klaempfl
This unit implements the base class for the register allocator
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.
****************************************************************************
}
{$i fpcdefs.inc}
{ Allow duplicate allocations, can be used to get the .s file written }
{ $define ALLOWDUPREG}
{#******************************************************************************
@abstract(Abstract register allocator unit)
Register allocator introduction.
Free Pascal uses a Chaitin style register allocator. We use a variant similair
to the one described in the book "Modern compiler implementation in C" by
Andrew W. Appel., published by Cambridge University Press.
The register allocator that is described by Appel uses a much improved way
of register coalescing, called "iterated register coalescing". Instead
of doing coalescing as a prepass to the register allocation, the coalescing
is done inside the register allocator. This has the advantage that the
register allocator can coalesce very aggresively without introducing spills.
Reading this book is recommended for a complete understanding. Here is a small
introduction.
The code generator thinks it has an infinite amount of registers. Our processor
has a limited amount of registers. Therefore we must reduce the amount of
registers until there are less enough to fit into the processors registers.
Registers can interfere or not interfere. If two imaginary registers interfere
they cannot be placed into the same psysical register. Reduction of registers
is done by:
- "coalescing" Two registers that do not interfere are combined
into one register.
- "spilling" A register is changed into a memory location and the generated
code is modified to use the memory location instead of the register.
Register allocation is a graph colouring problem. Each register is a colour, and
if two registers interfere there is a connection between them in the graph.
In addition to the imaginary registers in the code generator, the psysical
CPU registers are also present in this graph. This allows us to make
interferences between imaginary registers and cpu registers. This is very
usefull for describing archtectural constraints, like for example that
the div instruction modifies edx, so variables that are in use at that time
cannot be stored into edx. This can be modelled by making edx interfere
with those variables.
Graph colouring is an NP complete problem. Therefore we use an approximation
that pushes registers to colour on to a stack. This is done in the "simplify"
procedure.
The register allocator first checks which registers are a candidate for
coalescing.
*******************************************************************************}
unit rgobj;
interface
uses
cutils, cpubase,
aasmbase,aasmtai,aasmcpu,
cclasses,globtype,cgbase,node,cgobj,
{$ifdef delphi}
dmisc,
{$endif}
cpuinfo
;
const
ALL_OTHERREGISTERS=[low(tregisterindex)..high(tregisterindex)];
type
regvarother_longintarray = array[tregisterindex] of longint;
regvarother_booleanarray = array[tregisterindex] of boolean;
regvarint_longintarray = array[first_int_supreg..last_int_supreg] of longint;
regvarint_ptreearray = array[first_int_supreg..last_int_supreg] of tnode;
tpushedsavedloc = record
case byte of
0: (pushed: boolean);
1: (ofs: longint);
end;
tpushedsavedother = array[tregisterindex] of tpushedsavedloc;
Tinterferencebitmap=array[Tsuperregister] of set of Tsuperregister;
Tinterferenceadjlist=array[Tsuperregister] of Pstring;
Tinterferencegraph=record
bitmap:Tinterferencebitmap;
adjlist:Tinterferenceadjlist;
end;
Pinterferencegraph=^Tinterferencegraph;
Tmovelist=record
count:cardinal;
data:array[0..$ffff] of Tlinkedlistitem;
end;
Pmovelist=^Tmovelist;
{In the register allocator we keep track of move instructions.
These instructions are moved between five linked lists. There
is also a linked list per register to keep track about the moves
it is associated with. Because we need to determine quickly in
which of the five lists it is we add anu enumeradtion to each
move instruction.}
Tmoveset=(ms_coalesced_moves,ms_constrained_moves,ms_frozen_moves,
ms_worklist_moves,ms_active_moves);
Tmoveins=class(Tlinkedlistitem)
moveset:Tmoveset;
{ $ifdef ra_debug}
x,y:Tsuperregister;
{ $endif}
instruction:Taicpu;
end;
trgobj = class
{ The "usableregsxxx" contain all registers of type "xxx" that }
{ aren't currently allocated to a regvar. The "unusedregsxxx" }
{ contain all registers of type "xxx" that aren't currently }
{ allocated }
unusedregsfpu,usableregsfpu : Tsuperregisterset;
unusedregsmm,usableregsmm : Tsuperregisterset;
{ these counters contain the number of elements in the }
{ unusedregsxxx/usableregsxxx sets }
countunusedregsfpu,
countunusedregsmm : byte;
countusableregsaddr,
countusableregsfpu,
countusableregsmm : byte;
{ Contains the registers which are really used by the proc itself.
It doesn't take care of registers used by called procedures
}
used_in_proc_other : totherregisterset;
reg_pushes_other : regvarother_longintarray;
is_reg_var_other : regvarother_booleanarray;
regvar_loaded_other : regvarother_booleanarray;
{ tries to hold the amount of times which the current tree is processed }
t_times: longint;
constructor create;
{# Allocate a floating point register.}
function getregisterfpu(list: taasmoutput;size:Tcgsize) : tregister; virtual;
{# Free a floating point register.}
procedure ungetregisterfpu(list: taasmoutput; r : tregister); virtual;
function getregistermm(list: taasmoutput) : tregister; virtual;
procedure ungetregistermm(list: taasmoutput; r : tregister); virtual;
{# Tries to allocate the passed fpu register, if possible.}
function getexplicitregisterfpu(list : taasmoutput; r : Tregister) : tregister;virtual;
{# Deallocate any kind of register. }
procedure ungetregister(list: taasmoutput; r : tregister); virtual;
{# Saves register variables (restoring happens automatically).}
procedure saveotherregvars(list:Taasmoutput;const s:Totherregisterset);
{# Saves in temporary references (allocated via the temp. allocator)
the registers defined in @var(s). The registers are only saved
if they are currently in use, otherwise they are left as is.
On processors which have instructions which manipulate the stack,
this routine should be overriden for performance reasons.
@param(list) List to add the instruction to
@param(saved) Array of saved register information
@param(s) Registers which might require saving
}
procedure saveusedotherregisters(list:Taasmoutput;
var saved:Tpushedsavedother;
const s:Totherregisterset);virtual;
{# Restores the registers which were saved with a call
to @var(saveusedregisters).
On processors which have instructions which manipulate the stack,
this routine should be overriden for performance reasons.
}
procedure restoreusedotherregisters(list:Taasmoutput;
const saved:Tpushedsavedother);virtual;
procedure resetusableregisters;virtual;
protected
{ the following two contain the common (generic) code for all }
{ get- and ungetregisterxxx functions/procedures }
function getregistergenother(list: taasmoutput; const lowreg, highreg: tsuperregister;
var unusedregs:Tsuperregisterset;var countunusedregs:byte): tregister;
procedure ungetregistergen(list: taasmoutput; r: tregister;
const usableregs:tsuperregisterset;var unusedregs: tsuperregisterset; var countunusedregs: byte);
end;
{#------------------------------------------------------------------
This class implements the abstract register allocator. It is used by the
code generator to allocate and free registers which might be valid across
nodes. It also contains utility routines related to registers.
Some of the methods in this class should be overriden
by cpu-specific implementations.
--------------------------------------------------------------------}
Tregisterallocator=class
{# A register allocator is owned by a code generator.}
owner:Tcg;
preserved_by_proc,used_in_proc:Tsuperregisterset;
is_reg_var:Tsuperregisterset; {old regvars}
reg_var_loaded:Tsuperregisterset; {old regvars}
{# The register allocator assigns each register a colour.}
colour:array[Tsuperregister] of Tsuperregister;
spillednodes:string;
constructor create(Acpu_registers:byte;
Aregtype:Tregistertype;
const Ausable:string;
Afirst_imaginary:Tsuperregister;
Apreserved_by_proc:Tsuperregisterset);
destructor destroy;override;
{# Allocate a register. An internalerror will be generated if there is
no more free registers which can be allocated.}
function getregister(list:Taasmoutput;size:Tcgsize):Tregister;
procedure add_constraints(reg:Tregister);virtual;
{# Allocate an ABT register. An internalerror will be generated if there
are no more free registers that can be allocated. An explanantion of
abt registers can be found near the implementation.}
function getabtregister(list:Taasmoutput;size:Tcgsize):Tregister;
{# Get the register specified.}
procedure getexplicitregister(list:Taasmoutput;r:Tregister);
{# Get multiple registers specified.}
procedure allocexplicitregisters(list:Taasmoutput;r:Tsuperregisterset);
{# Free multiple registers specified.}
procedure deallocexplicitregisters(list:Taasmoutput;r:Tsuperregisterset);
{# Deallocate any kind of register }
procedure ungetregister(list:Taasmoutput;r:Tregister);virtual;
{# Do the register allocation.}
procedure do_register_allocation(list:Taasmoutput;headertai:tai);
{ procedure resetusableregisters;virtual;}
{ procedure makeregvar(reg:Tsuperregister);}
{$ifdef EXTDEBUG}
procedure writegraph(loopidx:longint);
{$endif EXTDEBUG}
procedure add_move_instruction(instr:Taicpu);
{# Prepare the register colouring.}
procedure prepare_colouring;
{# Clean up after register colouring.}
procedure epilogue_colouring;
{# Colour the registers; that is do the register allocation.}
procedure colour_registers;
{# Spills certain registers in the specified assembler list.}
function spill_registers(list:Taasmoutput;headertai:tai;const regs_to_spill:string):boolean;
{# Adds an interference edge.}
procedure add_edge(u,v:Tsuperregister);
protected
regtype:Tregistertype;
{# First imaginary register.}
first_imaginary,
{# Last register allocated.}
lastused,
{# Highest register allocated until now.}
maxreg:Tsuperregister;
usable_registers:string[32];
unusedregs,usableregs:Tsuperregisterset;
countusableregs:byte; {old regvars}
cpu_registers:byte;
igraph:Tinterferencegraph;
degree:array[0..255] of byte;
alias:array[Tsuperregister] of Tsuperregister;
simplifyworklist,freezeworklist,spillworklist:string;
coalescednodes:string;
selectstack:string;
abtlist:string;
movelist:array[Tsuperregister] of Pmovelist;
worklist_moves,active_moves,frozen_moves,
coalesced_moves,constrained_moves:Tlinkedlist;
procedure getregisterinline(list:Taasmoutput;position:Tai;subreg:Tsubregister;var result:Tregister);
procedure ungetregisterinline(list:Taasmoutput;position:Tai;r:Tregister);
procedure add_edges_used(u:Tsuperregister);
procedure add_to_movelist(u:Tsuperregister;data:Tlinkedlistitem);
function move_related(n:Tsuperregister):boolean;
procedure make_work_list;
procedure enable_moves(n:Tsuperregister);
procedure decrement_degree(m:Tsuperregister);
procedure simplify;
function get_alias(n:Tsuperregister):Tsuperregister;
procedure add_worklist(u:Tsuperregister);
function adjacent_ok(u,v:Tsuperregister):boolean;
function conservative(u,v:Tsuperregister):boolean;
procedure combine(u,v:Tsuperregister);
procedure coalesce;
procedure freeze_moves(u:Tsuperregister);
procedure freeze;
procedure select_spill;
procedure assign_colours;
procedure clear_interferences(u:Tsuperregister);
end;
const {# This value is used in tsaved. If the array value is equal
to this, then this means that this register is not used.}
reg_not_saved = $7fffffff;
first_reg = 0;
last_reg = 254;
maxspillingcounter = 20;
{ trerefence handling }
{# Clear to zero a treference }
procedure reference_reset(var ref : treference);
{# Clear to zero a treference, and set is base address
to base register.
}
procedure reference_reset_base(var ref : treference;base : tregister;offset : longint);
procedure reference_reset_symbol(var ref : treference;sym : tasmsymbol;offset : longint);
procedure reference_release(list: taasmoutput; const ref : treference);
{ This routine verifies if two references are the same, and
if so, returns TRUE, otherwise returns false.
}
function references_equal(sref : treference;dref : treference) : boolean;
{ tlocation handling }
procedure location_reset(var l : tlocation;lt:TCGLoc;lsize:TCGSize);
procedure location_release(list: taasmoutput; const l : tlocation);
procedure location_freetemp(list: taasmoutput; const l : tlocation);
procedure location_copy(var destloc:tlocation; const sourceloc : tlocation);
procedure location_swap(var destloc,sourceloc : tlocation);
implementation
uses
systems,{$ifdef EXTDEBUG}fmodule,{$endif}
globals,verbose,tgobj,regvars,procinfo;
{******************************************************************************
Tregisterallocator
******************************************************************************}
constructor Tregisterallocator.create(Acpu_registers:byte;
Aregtype:Tregistertype;
const Ausable:string;
Afirst_imaginary:Tsuperregister;
Apreserved_by_proc:Tsuperregisterset);
var i:Tsuperregister;
begin
used_in_proc:=[];
{ resetusableregisters;}
lastused:=0;
maxreg:=Afirst_imaginary;
first_imaginary:=Afirst_imaginary;
cpu_registers:=Acpu_registers;
regtype:=Aregtype;
unusedregs:=[first_reg..last_reg]; { 255 (RS_INVALID) can't be used }
{$ifdef powerpc}
preserved_by_proc:=[RS_R13..RS_R31];
{$else powerpc}
preserved_by_proc:=[];
{$endif powerpc}
fillchar(igraph,sizeof(igraph),0);
fillchar(degree,sizeof(degree),0);
{Precoloured nodes should have an infinite degree, which we can approach
by 255.}
for i:=0 to first_imaginary-1 do
degree[i]:=255;
fillchar(movelist,sizeof(movelist),0);
worklist_moves:=Tlinkedlist.create;
usable_registers:=Ausable;
abtlist:='';
fillchar(colour,sizeof(colour),RS_INVALID);
end;
destructor Tregisterallocator.destroy;
var i:Tsuperregister;
begin
for i:=low(Tsuperregister) to high(Tsuperregister) do
begin
if igraph.adjlist[i]<>nil then
dispose(igraph.adjlist[i]);
if movelist[i]<>nil then
dispose(movelist[i]);
end;
worklist_moves.free;
end;
function Tregisterallocator.getregister(list:Taasmoutput;size:Tcgsize):Tregister;
var i,p:Tsuperregister;
r:Tregister;
min : byte;
adj : pstring;
subreg:Tsubregister;
begin
subreg:=cgsize2subreg(size);
if maxreg<last_reg then
begin
inc(maxreg);
p:=maxreg;
min:=0;
end
else
begin
min:=$ff;
p:=first_imaginary;
for i:=first_imaginary to maxreg do
if (i in unusedregs) and
(pos(char(i),abtlist)=0) then
begin
adj:=igraph.adjlist[Tsuperregister(i)];
if adj=nil then
begin
p:=i;
min:=0;
break; {We won't find smaller ones.}
end
else
if length(adj^)<min then
begin
p:=i;
min:=length(adj^);
if min=0 then
break; {We won't find smaller ones.}
end;
end;
if min=$ff then
begin
{$ifdef ALLOWDUPREG}
result:=newreg(regtype,RS_INVALID,subreg);
exit;
{$else}
internalerror(10);
{$endif}
end;
end;
exclude(unusedregs,p);
include(used_in_proc,p);
r:=newreg(regtype,p,subreg);
list.concat(Tai_regalloc.alloc(r));
add_edges_used(p);
add_constraints(r);
result:=r;
end;
procedure Tregisterallocator.ungetregister(list:Taasmoutput;r:Tregister);
var supreg:Tsuperregister;
begin
supreg:=getsupreg(r);
if not (supreg in unusedregs) then
begin
include(unusedregs,supreg);
list.concat(Tai_regalloc.dealloc(r));
add_edges_used(supreg);
add_constraints(r);
end;
end;
procedure Tregisterallocator.getexplicitregister(list:Taasmoutput;r:Tregister);
var supreg:Tsuperregister;
begin
supreg:=getsupreg(r);
if supreg in unusedregs then
begin
exclude(unusedregs,supreg);
include(used_in_proc,supreg);
list.concat(Tai_regalloc.alloc(r));
add_edges_used(supreg);
add_constraints(r);
end
else
{$ifndef ALLOWDUPREG}
internalerror(200301103)
{$endif ALLOWDUPREG}
;
end;
procedure Tregisterallocator.allocexplicitregisters(list:Taasmoutput;r:Tsuperregisterset);
var reg:Tregister;
i:Tsuperregister;
begin
if unusedregs*r=r then
begin
unusedregs:=unusedregs-r;
used_in_proc:=used_in_proc+r;
for i:=0 to first_imaginary-1 do
if i in r then
begin
add_edges_used(i);
reg:=newreg(regtype,i,R_SUBWHOLE);
list.concat(Tai_regalloc.alloc(reg));
end;
end
else
{$ifndef ALLOWDUPREG}
internalerror(200305061)
{$endif ALLOWDUPREG}
;
end;
procedure Tregisterallocator.deallocexplicitregisters(list:Taasmoutput;r:Tsuperregisterset);
var reg:Tregister;
i:Tsuperregister;
begin
if unusedregs*r=[] then
begin
unusedregs:=unusedregs+r;
for i:=first_imaginary-1 downto 0 do
if i in r then
begin
reg:=newreg(regtype,i,R_SUBWHOLE);
list.concat(Tai_regalloc.dealloc(reg));
end;
end
else
internalerror(200305061);
end;
procedure Tregisterallocator.do_register_allocation(list:Taasmoutput;headertai:tai);
var spillingcounter:byte;
fastspill:boolean;
begin
{Do register allocation.}
spillingcounter:=0;
repeat
prepare_colouring;
colour_registers;
epilogue_colouring;
fastspill:=true;
if spillednodes<>'' then
begin
inc(spillingcounter);
if spillingcounter>maxspillingcounter then
internalerror(200309041);
fastspill:=spill_registers(list,headertai,spillednodes);
end;
until (spillednodes='') or not fastspill;
end;
procedure Tregisterallocator.add_constraints(reg:Tregister);
begin
end;
procedure Tregisterallocator.add_edge(u,v:Tsuperregister);
{This procedure will add an edge to the virtual interference graph.}
procedure addadj(u,v:Tsuperregister);
begin
if igraph.adjlist[u]=nil then
begin
getmem(igraph.adjlist[u],16);
igraph.adjlist[u]^:='';
end
else if (length(igraph.adjlist[u]^) and 15)=15 then
reallocmem(igraph.adjlist[u],length(igraph.adjlist[u]^)+16);
igraph.adjlist[u]^:=igraph.adjlist[u]^+char(v);
end;
begin
if (u<>v) and not(v in igraph.bitmap[u]) then
begin
include(igraph.bitmap[u],v);
include(igraph.bitmap[v],u);
{Precoloured nodes are not stored in the interference graph.}
if not(u in [first_int_supreg..last_int_supreg]) then
begin
addadj(u,v);
inc(degree[u]);
end;
if not(v in [first_int_supreg..last_int_supreg]) then
begin
addadj(v,u);
inc(degree[v]);
end;
end;
end;
procedure Tregisterallocator.add_edges_used(u:Tsuperregister);
var i:Tsuperregister;
begin
for i:=0 to maxreg do
if not(i in unusedregs) then
add_edge(u,i);
end;
{$ifdef EXTDEBUG}
procedure Tregisterallocator.writegraph(loopidx:longint);
{This procedure writes out the current interference graph in the
register allocator.}
var f:text;
i,j:Tsuperregister;
begin
assign(f,'igraph'+tostr(loopidx));
rewrite(f);
writeln(f,'Interference graph');
writeln(f);
write(f,' ');
for i:=0 to 15 do
for j:=0 to 15 do
write(f,hexstr(i,1));
writeln(f);
write(f,' ');
for i:=0 to 15 do
write(f,'0123456789ABCDEF');
writeln(f);
for i:=0 to 255 do
begin
write(f,hexstr(i,2):4);
for j:=0 to 255 do
if j in igraph.bitmap[i] then
write(f,'*')
else
write(f,'-');
writeln(f);
end;
close(f);
end;
{$endif EXTDEBUG}
procedure Tregisterallocator.add_to_movelist(u:Tsuperregister;data:Tlinkedlistitem);
begin
if movelist[u]=nil then
begin
getmem(movelist[u],64);
movelist[u]^.count:=0;
end
else if (movelist[u]^.count and 15)=15 then
reallocmem(movelist[u],(movelist[u]^.count+1)*4+64);
movelist[u]^.data[movelist[u]^.count]:=data;
inc(movelist[u]^.count);
end;
procedure Tregisterallocator.add_move_instruction(instr:Taicpu);
{This procedure notifies a certain as a move instruction so the
register allocator can try to eliminate it.}
var i:Tmoveins;
ssupreg,dsupreg:Tsuperregister;
begin
i:=Tmoveins.create;
i.moveset:=ms_worklist_moves;
i.instruction:=instr;
worklist_moves.insert(i);
ssupreg:=getsupreg(instr.oper[O_MOV_SOURCE].reg);
add_to_movelist(ssupreg,i);
dsupreg:=getsupreg(instr.oper[O_MOV_DEST].reg);
if ssupreg<>dsupreg then
{Avoid adding the same move instruction twice to a single register.}
add_to_movelist(dsupreg,i);
i.x:=ssupreg;
i.y:=dsupreg;
end;
function Tregisterallocator.move_related(n:Tsuperregister):boolean;
var i:cardinal;
begin
move_related:=false;
if movelist[n]<>nil then
begin
for i:=0 to movelist[n]^.count-1 do
if Tmoveins(movelist[n]^.data[i]).moveset in
[ms_worklist_moves,ms_active_moves] then
begin
move_related:=true;
break;
end;
end;
end;
procedure Tregisterallocator.make_work_list;
var n:Tsuperregister;
begin
{If we have 7 cpu registers, and the degree of a node is 7, we cannot
assign it to any of the registers, thus it is significant.}
for n:=first_imaginary to maxreg do
if degree[n]>=cpu_registers then
spillworklist:=spillworklist+char(n)
else if move_related(n) then
freezeworklist:=freezeworklist+char(n)
else
simplifyworklist:=simplifyworklist+char(n);
end;
procedure Tregisterallocator.prepare_colouring;
begin
make_work_list;
active_moves:=Tlinkedlist.create;
frozen_moves:=Tlinkedlist.create;
coalesced_moves:=Tlinkedlist.create;
constrained_moves:=Tlinkedlist.create;
fillchar(alias,sizeof(alias),0);
coalescednodes:='';
selectstack:='';
end;
procedure Tregisterallocator.enable_moves(n:Tsuperregister);
var m:Tlinkedlistitem;
i:cardinal;
begin
if movelist[n]<>nil then
for i:=0 to movelist[n]^.count-1 do
begin
m:=movelist[n]^.data[i];
if Tmoveins(m).moveset in [ms_worklist_moves,ms_active_moves] then
begin
if Tmoveins(m).moveset=ms_active_moves then
begin
{Move m from the set active_moves to the set worklist_moves.}
active_moves.remove(m);
Tmoveins(m).moveset:=ms_worklist_moves;
worklist_moves.concat(m);
end;
end;
end;
end;
procedure Tregisterallocator.decrement_degree(m:Tsuperregister);
var adj:Pstring;
d:byte;
i,p:byte;
n:char;
begin
d:=degree[m];
if degree[m]>0 then
dec(degree[m]);
if d=cpu_registers then
begin
{Enable moves for m.}
enable_moves(m);
{Enable moves for adjacent.}
adj:=igraph.adjlist[m];
if adj<>nil then
for i:=1 to length(adj^) do
begin
n:=adj^[i];
if (pos(n,selectstack) or pos(n,coalescednodes))=0 then
enable_moves(Tsuperregister(n));
end;
{Remove the node from the spillworklist.}
p:=pos(char(m),spillworklist);
if p=0 then
internalerror(200305301); {must be found}
if length(spillworklist)>1 then
spillworklist[p]:=spillworklist[length(spillworklist)];
dec(spillworklist[0]);
if move_related(m) then
freezeworklist:=freezeworklist+char(m)
else
simplifyworklist:=simplifyworklist+char(m);
end;
end;
procedure Tregisterallocator.simplify;
var adj:Pstring;
i,min,p:byte;
m:char;
n:Tsuperregister;
begin
{We the element with the least interferences out of the
simplifyworklist.}
min:=$ff;
p:=1;
for i:=1 to length(simplifyworklist) do
begin
adj:=igraph.adjlist[Tsuperregister(simplifyworklist[i])];
if adj=nil then
begin
min:=0;
break; {We won't find smaller ones.}
end
else
if length(adj^)<min then
begin
min:=length(adj^);
if min=0 then
break; {We won't find smaller ones.}
p:=i;
end;
end;
n:=Tsuperregister(simplifyworklist[p]);
if length(simplifyworklist)>1 then
simplifyworklist[p]:=simplifyworklist[length(simplifyworklist)];
dec(simplifyworklist[0]);
{Push it on the selectstack.}
selectstack:=selectstack+char(n);
adj:=igraph.adjlist[n];
if adj<>nil then
for i:=1 to length(adj^) do
begin
m:=adj^[i];
if ((pos(m,selectstack) or pos(m,coalescednodes))=0) and
not (Tsuperregister(m) in [first_int_supreg..last_int_supreg]) then
decrement_degree(Tsuperregister(m));
end;
end;
function Tregisterallocator.get_alias(n:Tsuperregister):Tsuperregister;
begin
while pos(char(n),coalescednodes)<>0 do
n:=alias[n];
get_alias:=n;
end;
procedure Tregisterallocator.add_worklist(u:Tsuperregister);
var p:byte;
begin
if not(u in [first_int_supreg..last_int_supreg]) and
not move_related(u) and
(degree[u]<cpu_registers) then
begin
p:=pos(char(u),freezeworklist);
if p=0 then
internalerror(200308161); {must be found}
if length(freezeworklist)>1 then
freezeworklist[p]:=freezeworklist[length(freezeworklist)];
dec(freezeworklist[0]);
simplifyworklist:=simplifyworklist+char(u);
end;
end;
function Tregisterallocator.adjacent_ok(u,v:Tsuperregister):boolean;
{Check wether u and v should be coalesced. u is precoloured.}
function ok(t,r:Tsuperregister):boolean;
begin
ok:=(degree[t]<cpu_registers) or
(t in [first_int_supreg..last_int_supreg]) or
(r in igraph.bitmap[t]);
end;
var adj:Pstring;
i:byte;
t:char;
begin
adjacent_ok:=true;
adj:=igraph.adjlist[v];
if adj<>nil then
for i:=1 to length(adj^) do
begin
t:=adj^[i];
if (pos(t,selectstack) or pos(t,coalescednodes))=0 then
if not ok(Tsuperregister(t),u) then
begin
adjacent_ok:=false;
break;
end;
end;
end;
function Tregisterallocator.conservative(u,v:Tsuperregister):boolean;
var adj:Pstring;
done:set of char; {To prevent that we count nodes twice.}
i,k:byte;
n:char;
begin
k:=0;
done:=[];
adj:=igraph.adjlist[u];
if adj<>nil then
for i:=1 to length(adj^) do
begin
n:=adj^[i];
if (pos(n,selectstack) or pos(n,coalescednodes))=0 then
begin
include(done,n);
if degree[Tsuperregister(n)]>=cpu_registers then
inc(k);
end;
end;
adj:=igraph.adjlist[v];
if adj<>nil then
for i:=1 to length(adj^) do
begin
n:=adj^[i];
if ((pos(n,selectstack) or pos(n,coalescednodes))=0) and
not (n in done) and
(degree[Tsuperregister(n)]>=cpu_registers) then
inc(k);
end;
conservative:=(k<cpu_registers);
end;
procedure Tregisterallocator.combine(u,v:Tsuperregister);
var add:boolean;
adj:Pstring;
i,p:byte;
n,o:cardinal;
t:char;
decrement:boolean;
begin
p:=pos(char(v),freezeworklist);
if p<>0 then
delete(freezeworklist,p,1)
else
delete(spillworklist,pos(char(v),spillworklist),1);
coalescednodes:=coalescednodes+char(v);
alias[v]:=u;
{Combine both movelists. Since the movelists are sets, only add
elements that are not already present.}
if assigned(movelist[v]) then
begin
for n:=0 to movelist[v]^.count-1 do
begin
add:=true;
for o:=0 to movelist[u]^.count-1 do
if movelist[u]^.data[o]=movelist[v]^.data[n] then
begin
add:=false;
break;
end;
if add then
add_to_movelist(u,movelist[v]^.data[n]);
end;
enable_moves(v);
end;
adj:=igraph.adjlist[v];
if adj<>nil then
for i:=1 to length(adj^) do
begin
t:=adj^[i];
if (pos(t,selectstack) or pos(t,coalescednodes))=0 then
begin
decrement:=(Tsuperregister(t)<>u) and not(u in igraph.bitmap[Tsuperregister(t)]);
add_edge(Tsuperregister(t),u);
{Do not call decrement_degree because it might move nodes between
lists while the degree does not change (add_edge will increase it).
Instead, we will decrement manually. (Only if the degree has been
increased.)}
if decrement and not (Tsuperregister(t) in [first_int_supreg..last_int_supreg])
and (degree[Tsuperregister(t)]>0) then
dec(degree[Tsuperregister(t)]);
end;
end;
p:=pos(char(u),freezeworklist);
if (degree[u]>=cpu_registers) and (p<>0) then
begin
delete(freezeworklist,p,1);
spillworklist:=spillworklist+char(u);
end;
end;
procedure Tregisterallocator.coalesce;
var m:Tmoveins;
x,y,u,v:Tsuperregister;
begin
m:=Tmoveins(worklist_moves.getfirst);
x:=get_alias(getsupreg(m.instruction.oper[0].reg));
y:=get_alias(getsupreg(m.instruction.oper[1].reg));
if y in [first_int_supreg..last_int_supreg] then
begin
u:=y;
v:=x;
end
else
begin
u:=x;
v:=y;
end;
if (u=v) then
begin
m.moveset:=ms_coalesced_moves; {Already coalesced.}
coalesced_moves.insert(m);
add_worklist(u);
end
{Do u and v interfere? In that case the move is constrained. Two
precoloured nodes interfere allways. If v is precoloured, by the above
code u is precoloured, thus interference...}
else if (v in [first_int_supreg..last_int_supreg]) or (u in igraph.bitmap[v]) then
begin
m.moveset:=ms_constrained_moves; {Cannot coalesce yet...}
constrained_moves.insert(m);
add_worklist(u);
add_worklist(v);
end
{Next test: is it possible and a good idea to coalesce??}
else if ((u in [first_int_supreg..last_int_supreg]) and adjacent_ok(u,v)) or
(not(u in [first_int_supreg..last_int_supreg]) and conservative(u,v)) then
begin
m.moveset:=ms_coalesced_moves; {Move coalesced!}
coalesced_moves.insert(m);
combine(u,v);
add_worklist(u);
end
else
begin
m.moveset:=ms_active_moves;
active_moves.insert(m);
end;
end;
procedure Tregisterallocator.freeze_moves(u:Tsuperregister);
var i:cardinal;
m:Tlinkedlistitem;
v,x,y:Tsuperregister;
begin
if movelist[u]<>nil then
for i:=0 to movelist[u]^.count-1 do
begin
m:=movelist[u]^.data[i];
if Tmoveins(m).moveset in [ms_worklist_moves,ms_active_moves] then
begin
x:=getsupreg(Tmoveins(m).instruction.oper[0].reg);
y:=getsupreg(Tmoveins(m).instruction.oper[1].reg);
if get_alias(y)=get_alias(u) then
v:=get_alias(x)
else
v:=get_alias(y);
{Move m from active_moves/worklist_moves to frozen_moves.}
if Tmoveins(m).moveset=ms_active_moves then
active_moves.remove(m)
else
worklist_moves.remove(m);
Tmoveins(m).moveset:=ms_frozen_moves;
frozen_moves.insert(m);
if not(v in [first_int_supreg..last_int_supreg]) and
not(move_related(v)) and
(degree[v]<cpu_registers) then
begin
delete(freezeworklist,pos(char(v),freezeworklist),1);
simplifyworklist:=simplifyworklist+char(v);
end;
end;
end;
end;
procedure Tregisterallocator.freeze;
var n:Tsuperregister;
begin
{We need to take a random element out of the freezeworklist. We take
the last element. Dirty code!}
n:=Tsuperregister(freezeworklist[byte(freezeworklist[0])]);
dec(freezeworklist[0]);
{Add it to the simplifyworklist.}
simplifyworklist:=simplifyworklist+char(n);
freeze_moves(n);
end;
procedure Tregisterallocator.select_spill;
var n:char;
begin
{This code is WAY too naive. We need not to select just a register, but
the register that is used the least...}
n:=spillworklist[byte(spillworklist[0])];
dec(spillworklist[0]);
simplifyworklist:=simplifyworklist+n;
freeze_moves(Tsuperregister(n));
end;
procedure Tregisterallocator.assign_colours;
{Assign_colours assigns the actual colours to the registers.}
var adj:Pstring;
i,j,k:byte;
n,a,c:Tsuperregister;
adj_colours,colourednodes:set of Tsuperregister;
w:char;
begin
spillednodes:='';
{Reset colours}
for i:=0 to maxreg do
colour[i]:=i;
{Colour the cpu registers...}
colourednodes:=[first_int_supreg..last_int_supreg];
{Now colour the imaginary registers on the select-stack.}
for i:=length(selectstack) downto 1 do
begin
n:=Tsuperregister(selectstack[i]);
{Create a list of colours that we cannot assign to n.}
adj_colours:=[];
adj:=igraph.adjlist[n];
if adj<>nil then
for j:=1 to length(adj^) do
begin
w:=adj^[j];
a:=get_alias(Tsuperregister(w));
if a in colourednodes then
include(adj_colours,colour[a]);
end;
include(adj_colours,RS_STACK_POINTER_REG);
{Assume a spill by default...}
spillednodes:=spillednodes+char(n);
{Search for a colour not in this list.}
for k:=1 to length(usable_registers) do
begin
c:=Tsuperregister(usable_registers[k]);
if not(c in adj_colours) then
begin
colour[n]:=c;
dec(spillednodes[0]); {Colour found: no spill.}
include(colourednodes,n);
if n in used_in_proc then
include(used_in_proc,c);
break;
end;
end;
end;
{Finally colour the nodes that were coalesced.}
for i:=1 to length(coalescednodes) do
begin
n:=Tsuperregister(coalescednodes[i]);
k:=get_alias(n);
colour[n]:=colour[k];
if n in used_in_proc then
include(used_in_proc,colour[k]);
end;
{$ifdef ra_debug}
if aktfilepos.line=2502 then
begin
writeln('colourlist ',length(freezeworklist));
for i:=0 to maxintreg do
writeln(i:4,' ',colour[i]:4)
end;
{$endif ra_debug}
end;
procedure Tregisterallocator.colour_registers;
begin
repeat
if length(simplifyworklist)<>0 then
simplify
else if not(worklist_moves.empty) then
coalesce
else if length(freezeworklist)<>0 then
freeze
else if length(spillworklist)<>0 then
select_spill;
until (length(simplifyworklist)=0) and
worklist_moves.empty and
(length(freezeworklist)=0) and
(length(spillworklist)=0);
assign_colours;
end;
procedure Tregisterallocator.epilogue_colouring;
{
procedure move_to_worklist_moves(list:Tlinkedlist);
var p:Tlinkedlistitem;
begin
p:=list.first;
while p<>nil do
begin
Tmoveins(p).moveset:=ms_worklist_moves;
p:=p.next;
end;
worklist_moves.concatlist(list);
end;
}
var i:Tsuperregister;
begin
worklist_moves.clear;
{$ifdef Principle_wrong_by_definition}
{Move everything back to worklist_moves.}
move_to_worklist_moves(active_moves);
move_to_worklist_moves(frozen_moves);
move_to_worklist_moves(coalesced_moves);
move_to_worklist_moves(constrained_moves);
{$endif Principle_wrong_by_definition}
active_moves.destroy;
active_moves:=nil;
frozen_moves.destroy;
frozen_moves:=nil;
coalesced_moves.destroy;
coalesced_moves:=nil;
constrained_moves.destroy;
constrained_moves:=nil;
for i:=0 to 255 do
if movelist[i]<>nil then
begin
dispose(movelist[i]);
movelist[i]:=0;
end;
end;
procedure Tregisterallocator.clear_interferences(u:Tsuperregister);
{Remove node u from the interference graph and remove all collected
move instructions it is associated with.}
var i:byte;
j,k,count:cardinal;
v:Tsuperregister;
m,n:Tmoveins;
begin
if igraph.adjlist[u]<>nil then
begin
for i:=1 to length(igraph.adjlist[u]^) do
begin
v:=Tsuperregister(igraph.adjlist[u]^[i]);
{Remove (u,v) and (v,u) from bitmap.}
exclude(igraph.bitmap[u],v);
exclude(igraph.bitmap[v],u);
{Remove (v,u) from adjacency list.}
if igraph.adjlist[v]<>nil then
begin
delete(igraph.adjlist[v]^,pos(char(v),igraph.adjlist[v]^),1);
if length(igraph.adjlist[v]^)=0 then
begin
dispose(igraph.adjlist[v]);
igraph.adjlist[v]:=nil;
end;
end;
end;
{Remove ( u,* ) from adjacency list.}
dispose(igraph.adjlist[u]);
igraph.adjlist[u]:=nil;
end;
{$ifdef Principle_wrong_by_definition}
{Now remove the moves.}
if movelist[u]<>nil then
begin
for j:=0 to movelist[u]^.count-1 do
begin
m:=Tmoveins(movelist[u]^.data[j]);
{Get the other register of the move instruction.}
v:=m.instruction.oper[0].reg.number shr 8;
if v=u then
v:=m.instruction.oper[1].reg.number shr 8;
repeat
repeat
if (u<>v) and (movelist[v]<>nil) then
begin
{Remove the move from it's movelist.}
count:=movelist[v]^.count-1;
for k:=0 to count do
if m=movelist[v]^.data[k] then
begin
if k<>count then
movelist[v]^.data[k]:=movelist[v]^.data[count];
dec(movelist[v]^.count);
if count=0 then
begin
dispose(movelist[v]);
movelist[v]:=nil;
end;
break;
end;
end;
{The complexity is enourmous: the register might have been
coalesced. In that case it's movelists have been added to
it's coalescing alias. (DM)}
v:=alias[v];
until v=0;
{And also register u might have been coalesced.}
u:=alias[u];
until u=0;
case m.moveset of
ms_coalesced_moves:
coalesced_moves.remove(m);
ms_constrained_moves:
constrained_moves.remove(m);
ms_frozen_moves:
frozen_moves.remove(m);
ms_worklist_moves:
worklist_moves.remove(m);
ms_active_moves:
active_moves.remove(m);
end;
end;
dispose(movelist[u]);
movelist[u]:=nil;
end;
{$endif Principle_wrong_by_definition}
end;
procedure Tregisterallocator.getregisterinline(list:Taasmoutput;
position:Tai;subreg:Tsubregister;var result:Tregister);
var min,p,i:Tsuperregister;
r:Tregister;
adj:Pstring;
begin
if maxreg<last_reg then
begin
inc(maxreg);
p:=maxreg;
min:=0;
end
else
begin
min:=$ff;
p:=first_imaginary;
for i:=first_imaginary to maxreg do
if (i in unusedregs) and
(pos(char(i),abtlist)=0) and
(pos(char(i),spillednodes)=0) then
begin
adj:=igraph.adjlist[Tsuperregister(i)];
if adj=nil then
begin
p:=i;
min:=0;
break; {We won't find smaller ones.}
end
else
if length(adj^)<min then
begin
p:=i;
min:=length(adj^);
if min=0 then
break; {We won't find smaller ones.}
end;
end;
if min=$ff then
begin
{$ifdef ALLOWDUPREG}
result:=newreg(regtype,RS_INVALID,subreg);
exit;
{$else}
internalerror(10);
{$endif}
end;
end;
{$ifdef ra_debug}
writeln('Spilling temp: ',p,' min ',min);
{$endif ra_debug}
exclude(unusedregs,p);
include(used_in_proc,p);
r:=newreg(regtype,p,subreg);
if position=nil then
list.insert(Tai_regalloc.alloc(r))
else
list.insertafter(Tai_regalloc.alloc(r),position);
add_edges_used(p);
add_constraints(r);
result:=r;
end;
{In some cases we can get in big trouble. See this example:
; register reg23d released
; register eax allocated
; register ebx allocated
; register ecx allocated
; register edx allocated
; register esi allocated
; register edi allocated
call [reg23d]
This code is ok, *except* when reg23d is spilled. In that case the
spilled would introduce a help register which can never get
allocated to a real register because it interferes with all of them.
To solve this we introduce the ABT ("avoid big trouble :)" ) registers.
If you allocate an ABT register you get a register that has less
than cpu_register interferences and will not be allocated ever again
by the normal register get procedures. In other words it is for sure it
will never get spilled.}
function Tregisterallocator.getabtregister(list:Taasmoutput;
size:Tcgsize):Tregister;
var p,i:Tsuperregister;
r:Tregister;
subreg:tsubregister;
found:boolean;
min : byte;
adj:Pstring;
begin
min:=$ff;
for i:=1 to length(abtlist) do
if Tsuperregister(abtlist[i]) in unusedregs then
begin
p:=tsuperregister(abtlist[i]);
min:=0;
break;
end;
if min>0 then
begin
if maxreg<last_reg then
begin
inc(maxreg);
p:=maxreg;
min:=0;
end
else
begin
p:=first_imaginary;
for i:=first_imaginary to maxreg do
if (i in unusedregs) and
((igraph.adjlist[i]=nil) or
(length(igraph.adjlist[i]^)<cpu_registers)) then
begin
adj:=igraph.adjlist[i];
if adj=nil then
begin
p:=i;
min:=0;
break; {We won't find smaller ones.}
end
else
if length(adj^)<min then
begin
p:=i;
min:=length(adj^);
if min=0 then
break; {We won't find smaller ones.}
end;
end;
end;
if min=$ff then
begin
{$ifdef ALLOWDUPREG}
result:=newreg(regtype,RS_INVALID,cgsize2subreg(size));
exit;
{$else}
internalerror(10);
{$endif}
end;
end;
exclude(unusedregs,p);
include(used_in_proc,p);
subreg:=cgsize2subreg(size);
r:=newreg(regtype,p,subreg);
list.concat(Tai_regalloc.alloc(r));
result:=r;
add_edges_used(p);
add_constraints(r);
if pos(char(p),abtlist)=0 then
abtlist:=abtlist+char(p);
end;
procedure Tregisterallocator.ungetregisterinline(list:Taasmoutput;
position:Tai;r:Tregister);
var supreg:Tsuperregister;
begin
supreg:=getsupreg(r);
include(unusedregs,supreg);
if position=nil then
list.insert(Tai_regalloc.dealloc(r))
else
list.insertafter(Tai_regalloc.dealloc(r),position);
add_edges_used(supreg);
add_constraints(r);
end;
function Tregisterallocator.spill_registers(list:Taasmoutput;headertai:tai;const regs_to_spill:string):boolean;
{Returns true if any help registers have been used.}
var i:byte;
p,q:Tai;
regs_to_spill_set:Tsuperregisterset;
spill_temps:^Tspill_temp_list;
supreg : tsuperregister;
templist : taasmoutput;
begin
spill_registers:=false;
unusedregs:=[first_reg..last_reg];
fillchar(degree,sizeof(degree),0);
{Precoloured nodes should have an infinite degree, which we can approach
by 255.}
for i:=first_int_supreg to last_int_supreg do
degree[i]:=255;
{ exclude(unusedregs,RS_STACK_POINTER_REG);}
if current_procinfo.framepointer=NR_FRAME_POINTER_REG then
{Make sure the register allocator won't allocate registers into ebp.}
exclude(unusedregs,RS_FRAME_POINTER_REG);
new(spill_temps);
fillchar(spill_temps^,sizeof(spill_temps^),0);
regs_to_spill_set:=[];
{ Allocate temps and insert in front of the list }
templist:=taasmoutput.create;
for i:=1 to length(regs_to_spill) do
begin
{Alternative representation.}
include(regs_to_spill_set,Tsuperregister(regs_to_spill[i]));
{Clear all interferences of the spilled register.}
clear_interferences(Tsuperregister(regs_to_spill[i]));
{Get a temp for the spilled register}
tg.gettemp(templist,4,tt_noreuse,spill_temps^[Tsuperregister(regs_to_spill[i])]);
end;
list.insertlistafter(headertai,templist);
templist.free;
{ Walk through all instructions, we can start with the headertai,
because before the header tai is only symbols }
p:=headertai;
while assigned(p) do
begin
case p.typ of
ait_regalloc:
begin
{A register allocation of a spilled register can be removed.}
supreg:=getsupreg(Tai_regalloc(p).reg);
if supreg in regs_to_spill_set then
begin
q:=p;
p:=Tai(p.next);
list.remove(q);
continue;
end
else
if Tai_regalloc(p).allocation then
exclude(unusedregs,supreg)
else
include(unusedregs,supreg);
end;
ait_instruction:
begin
aktfilepos:=Taicpu_abstract(p).fileinfo;
if Taicpu_abstract(p).spill_registers(list,@getregisterinline,
@ungetregisterinline,
regs_to_spill_set,
unusedregs,
spill_temps^) then
spill_registers:=true;
if Taicpu_abstract(p).is_move then
add_move_instruction(Taicpu(p));
end;
end;
p:=Tai(p.next);
end;
aktfilepos:=current_procinfo.exitpos;
for i:=1 to length(regs_to_spill) do
tg.ungettemp(list,spill_temps^[Tsuperregister(regs_to_spill[i])]);
dispose(spill_temps);
end;
{******************************************************************************
Trgobj
******************************************************************************}
constructor Trgobj.create;
var i:Tsuperregister;
begin
used_in_proc_other:=[];
t_times := 0;
resetusableregisters;
unusedregsfpu:=usableregsfpu;
unusedregsmm:=usableregsmm;
countunusedregsfpu:=countusableregsfpu;
countunusedregsmm:=countusableregsmm;
end;
function trgobj.getregistergenother(list: taasmoutput; const lowreg, highreg: tsuperregister;
var unusedregs: tsuperregisterset; var countunusedregs: byte): tregister;
var
i: tsuperregister;
r: Tregister;
begin
for i:=lowreg to highreg do
begin
if i in unusedregs then
begin
exclude(unusedregs,i);
include(used_in_proc_other,i);
dec(countunusedregs);
{$warning Only FPU Registers supported}
r:=newreg(R_FPUREGISTER,i,R_SUBNONE);
list.concat(tai_regalloc.alloc(r));
result := r;
exit;
end;
end;
internalerror(10);
end;
procedure trgobj.ungetregistergen(list: taasmoutput; r: tregister;
const usableregs: tsuperregisterset; var unusedregs: tsuperregisterset; var countunusedregs: byte);
var
supreg : tsuperregister;
begin
supreg:=getsupreg(r);
{ takes much time }
if not(supreg in usableregs) then
exit;
if (supreg in unusedregs) then
exit
else
inc(countunusedregs);
include(unusedregs,supreg);
list.concat(tai_regalloc.dealloc(r));
end;
{ tries to allocate the passed register, if possible }
function trgobj.getexplicitregisterfpu(list : taasmoutput; r : Tregister) : tregister;
var
supreg : tsuperregister;
begin
supreg:=getsupreg(r);
if supreg in unusedregsfpu then
begin
dec(countunusedregsfpu);
exclude(unusedregsfpu,supreg);
include(used_in_proc_other,supreg);
list.concat(tai_regalloc.alloc(r));
getexplicitregisterfpu:=r;
end
else
{$warning Size for FPU reg is maybe not correct}
getexplicitregisterfpu:=getregisterfpu(list,OS_F32);
end;
function trgobj.getregisterfpu(list: taasmoutput;size:Tcgsize) : tregister;
begin
if countunusedregsfpu=0 then
internalerror(10);
{$warning TODO firstsavefpureg}
result := getregistergenother(list,firstsavefpureg,lastsavefpureg,
unusedregsfpu,countunusedregsfpu);
end;
procedure trgobj.ungetregisterfpu(list : taasmoutput; r : tregister);
begin
ungetregistergen(list,r,usableregsfpu,unusedregsfpu,
countunusedregsfpu);
end;
function trgobj.getregistermm(list: taasmoutput) : tregister;
begin
if countunusedregsmm=0 then
internalerror(10);
result := getregistergenother(list,firstsavemmreg,lastsavemmreg,
unusedregsmm,countunusedregsmm);
end;
procedure trgobj.ungetregistermm(list: taasmoutput; r: tregister);
begin
ungetregistergen(list,r,usableregsmm,unusedregsmm,
countunusedregsmm);
end;
procedure trgobj.ungetregister(list: taasmoutput; r : tregister);
begin
if r=NR_NO then
exit;
if getregtype(r)=R_FPUREGISTER then
ungetregisterfpu(list,r)
else if getregtype(r)=R_MMXREGISTER then
ungetregistermm(list,r)
else internalerror(2002070602);
end;
procedure trgobj.saveotherregvars(list: taasmoutput; const s: totherregisterset);
var
r: Tregister;
begin
if not(cs_regvars in aktglobalswitches) then
exit;
{$warning TODO firstsavefpureg}
{
if firstsavefpureg <> NR_NO then
for r.enum := firstsavefpureg to lastsavefpureg do
if is_reg_var_other[r.enum] and
(r.enum in s) then
store_regvar(list,r);
if firstsavemmreg <> R_NO then
for r.enum := firstsavemmreg to lastsavemmreg do
if is_reg_var_other[r.enum] and
(r.enum in s) then
store_regvar(list,r);
}
end;
procedure trgobj.saveusedotherregisters(list: taasmoutput;
var saved : tpushedsavedother; const s: totherregisterset);
var
r : tregister;
hr : treference;
begin
used_in_proc_other:=used_in_proc_other + s;
{$warning TODO firstsavefpureg}
(*
{ don't try to save the fpu registers if not desired (e.g. for }
{ the 80x86) }
if firstsavefpureg <> R_NO then
for r.enum:=firstsavefpureg to lastsavefpureg do
begin
saved[r.enum].ofs:=reg_not_saved;
{ if the register is used by the calling subroutine and if }
{ it's not a regvar (those are handled separately) }
if not is_reg_var_other[r.enum] and
(r.enum in s) and
{ and is present in use }
not(r.enum in unusedregsfpu) then
begin
{ then save it }
tg.GetTemp(list,extended_size,tt_persistent,hr);
saved[r.enum].ofs:=hr.offset;
cg.a_loadfpu_reg_ref(list,OS_FLOAT,r,hr);
cg.a_reg_dealloc(list,r);
include(unusedregsfpu,r.enum);
inc(countunusedregsfpu);
end;
end;
{ don't save the vector registers if there's no support for them }
if firstsavemmreg <> R_NO then
for r.enum:=firstsavemmreg to lastsavemmreg do
begin
saved[r.enum].ofs:=reg_not_saved;
{ if the register is in use and if it's not a regvar (those }
{ are handled separately), save it }
if not is_reg_var_other[r.enum] and
(r.enum in s) and
{ and is present in use }
not(r.enum in unusedregsmm) then
begin
{ then save it }
tg.GetTemp(list,mmreg_size,tt_persistent,hr);
saved[r.enum].ofs:=hr.offset;
cg.a_loadmm_reg_ref(list,r,hr);
cg.a_reg_dealloc(list,r);
include(unusedregsmm,r.enum);
inc(countunusedregsmm);
end;
end;
*)
end;
procedure trgobj.restoreusedotherregisters(list : taasmoutput;
const saved : tpushedsavedother);
var
r,r2 : tregister;
hr : treference;
begin
{$warning TODO firstsavefpureg}
(*
if firstsavemmreg <> R_NO then
for r.enum:=lastsavemmreg downto firstsavemmreg do
begin
if saved[r.enum].ofs <> reg_not_saved then
begin
r2.enum:=R_INTREGISTER;
r2.number:=NR_FRAME_POINTER_REG;
reference_reset_base(hr,r2,saved[r.enum].ofs);
cg.a_reg_alloc(list,r);
cg.a_loadmm_ref_reg(list,hr,r);
if not (r.enum in unusedregsmm) then
{ internalerror(10)
in n386cal we always save/restore the reg *state*
using save/restoreunusedstate -> the current state
may not be real (JM) }
else
begin
dec(countunusedregsmm);
exclude(unusedregsmm,r.enum);
end;
tg.UnGetTemp(list,hr);
end;
end;
if firstsavefpureg <> R_NO then
for r.enum:=lastsavefpureg downto firstsavefpureg do
begin
if saved[r.enum].ofs <> reg_not_saved then
begin
r2.enum:=R_INTREGISTER;
r2.number:=NR_FRAME_POINTER_REG;
reference_reset_base(hr,r2,saved[r.enum].ofs);
cg.a_reg_alloc(list,r);
cg.a_loadfpu_ref_reg(list,OS_FLOAT,hr,r);
if not (r.enum in unusedregsfpu) then
{ internalerror(10)
in n386cal we always save/restore the reg *state*
using save/restoreunusedstate -> the current state
may not be real (JM) }
else
begin
dec(countunusedregsfpu);
exclude(unusedregsfpu,r.enum);
end;
tg.UnGetTemp(list,hr);
end;
end;
*)
end;
procedure trgobj.resetusableregisters;
begin
{ initialize fields with constant values from cpubase }
countusableregsfpu := cpubase.c_countusableregsfpu;
countusableregsmm := cpubase.c_countusableregsmm;
usableregsfpu := cpubase.usableregsfpu;
usableregsmm := cpubase.usableregsmm;
end;
{****************************************************************************
TReference
****************************************************************************}
procedure reference_reset(var ref : treference);
begin
FillChar(ref,sizeof(treference),0);
{$ifdef arm}
ref.signindex:=1;
{$endif arm}
end;
procedure reference_reset_base(var ref : treference;base : tregister;offset : longint);
begin
reference_reset(ref);
ref.base:=base;
ref.offset:=offset;
end;
procedure reference_reset_symbol(var ref : treference;sym : tasmsymbol;offset : longint);
begin
reference_reset(ref);
ref.symbol:=sym;
ref.offset:=offset;
end;
procedure reference_release(list: taasmoutput; const ref : treference);
begin
cg.ungetreference(list,ref);
end;
function references_equal(sref : treference;dref : treference):boolean;
begin
references_equal:=CompareByte(sref,dref,sizeof(treference))=0;
end;
{****************************************************************************
TLocation
****************************************************************************}
procedure location_reset(var l : tlocation;lt:TCGLoc;lsize:TCGSize);
begin
FillChar(l,sizeof(tlocation),0);
l.loc:=lt;
l.size:=lsize;
{$ifdef arm}
if l.loc in [LOC_REFERENCE,LOC_CREFERENCE] then
l.reference.signindex:=1;
{$endif arm}
end;
procedure location_release(list: taasmoutput; const l : tlocation);
begin
case l.loc of
LOC_REGISTER,LOC_CREGISTER :
begin
cg.ungetregister(list,l.register);
if l.size in [OS_64,OS_S64] then
cg.ungetregister(list,l.registerhigh);
end;
LOC_FPUREGISTER,LOC_CFPUREGISTER :
cg.ungetregister(list,l.register);
LOC_CREFERENCE,LOC_REFERENCE :
cg.ungetreference(list, l.reference);
end;
end;
procedure location_freetemp(list:taasmoutput; const l : tlocation);
begin
if (l.loc in [LOC_REFERENCE,LOC_CREFERENCE]) then
tg.ungetiftemp(list,l.reference);
end;
procedure location_copy(var destloc:tlocation; const sourceloc : tlocation);
begin
destloc:=sourceloc;
end;
procedure location_swap(var destloc,sourceloc : tlocation);
var
swapl : tlocation;
begin
swapl := destloc;
destloc := sourceloc;
sourceloc := swapl;
end;
end.
{
$Log$
Revision 1.82 2003-10-09 21:31:37 daniel
* Register allocator splitted, ans abstract now
Revision 1.81 2003/10/01 20:34:49 peter
* procinfo unit contains tprocinfo
* cginfo renamed to cgbase
* moved cgmessage to verbose
* fixed ppc and sparc compiles
Revision 1.80 2003/09/30 19:54:42 peter
* reuse registers with the least conflicts
Revision 1.79 2003/09/29 20:58:56 peter
* optimized releasing of registers
Revision 1.78 2003/09/28 13:41:12 peter
* return reg 255 when allowdupreg is defined
Revision 1.77 2003/09/25 16:19:32 peter
* fix filepositions
* insert spill temp allocations at the start of the proc
Revision 1.76 2003/09/16 16:17:01 peter
* varspez in calls to push_addr_param
Revision 1.75 2003/09/12 19:07:42 daniel
* Fixed fast spilling functionality by re-adding the code that initializes
precoloured nodes to degree 255. I would like to play hangman on the one
who removed that code.
Revision 1.74 2003/09/11 11:54:59 florian
* improved arm code generation
* move some protected and private field around
* the temp. register for register parameters/arguments are now released
before the move to the parameter register is done. This improves
the code in a lot of cases.
Revision 1.73 2003/09/09 20:59:27 daniel
* Adding register allocation order
Revision 1.72 2003/09/09 15:55:44 peter
* use register with least interferences in spillregister
Revision 1.71 2003/09/07 22:09:35 peter
* preparations for different default calling conventions
* various RA fixes
Revision 1.70 2003/09/03 21:06:45 peter
* fixes for FPU register allocation
Revision 1.69 2003/09/03 15:55:01 peter
* NEWRA branch merged
Revision 1.68 2003/09/03 11:18:37 florian
* fixed arm concatcopy
+ arm support in the common compiler sources added
* moved some generic cg code around
+ tfputype added
* ...
Revision 1.67.2.5 2003/08/31 20:44:07 peter
* fixed getexplicitregisterint tregister value
Revision 1.67.2.4 2003/08/31 20:40:50 daniel
* Fixed add_edges_used
Revision 1.67.2.3 2003/08/29 17:28:59 peter
* next batch of updates
Revision 1.67.2.2 2003/08/28 18:35:08 peter
* tregister changed to cardinal
Revision 1.67.2.1 2003/08/27 19:55:54 peter
* first tregister patch
Revision 1.67 2003/08/23 10:46:21 daniel
* Register allocator bugfix for h2pas
Revision 1.66 2003/08/17 16:59:20 jonas
* fixed regvars so they work with newra (at least for ppc)
* fixed some volatile register bugs
+ -dnotranslation option for -dnewra, which causes the registers not to
be translated from virtual to normal registers. Requires support in
the assembler writer as well, which is only implemented in aggas/
agppcgas currently
Revision 1.65 2003/08/17 14:32:48 daniel
* Precoloured nodes now have an infinite degree approached with 255,
like they should.
Revision 1.64 2003/08/17 08:48:02 daniel
* Another register allocator bug fixed.
* cpu_registers set to 6 for i386
Revision 1.63 2003/08/09 18:56:54 daniel
* cs_regalloc renamed to cs_regvars to avoid confusion with register
allocator
* Some preventive changes to i386 spillinh code
Revision 1.62 2003/08/03 14:09:50 daniel
* Fixed a register allocator bug
* Figured out why -dnewra generates superfluous "mov reg1,reg2"
statements: changes in location_force. These moves are now no longer
constrained so they are optimized away.
Revision 1.61 2003/07/21 13:32:39 jonas
* add_edges_used() is now also called for registers allocated with
getexplicitregisterint()
* writing the intereference graph is now only done with -dradebug2 and
the created files are now called "igraph.<module_name>"
Revision 1.60 2003/07/06 15:31:21 daniel
* Fixed register allocator. *Lots* of fixes.
Revision 1.59 2003/07/06 15:00:47 jonas
* fixed my previous completely broken commit. It's not perfect though,
registers > last_int_supreg and < max_intreg may still be "translated"
Revision 1.58 2003/07/06 14:45:05 jonas
* support integer registers that are not managed by newra (ie. don't
translate register numbers that fall outside the range
first_int_supreg..last_int_supreg)
Revision 1.57 2003/07/02 22:18:04 peter
* paraloc splitted in callerparaloc,calleeparaloc
* sparc calling convention updates
Revision 1.56 2003/06/17 16:34:44 jonas
* lots of newra fixes (need getfuncretparaloc implementation for i386)!
* renamed all_intregisters to volatile_intregisters and made it
processor dependent
Revision 1.55 2003/06/14 14:53:50 jonas
* fixed newra cycle for x86
* added constants for indicating source and destination operands of the
"move reg,reg" instruction to aasmcpu (and use those in rgobj)
Revision 1.54 2003/06/13 21:19:31 peter
* current_procdef removed, use current_procinfo.procdef instead
Revision 1.53 2003/06/12 21:11:10 peter
* ungetregisterfpu gets size parameter
Revision 1.52 2003/06/12 16:43:07 peter
* newra compiles for sparc
Revision 1.51 2003/06/09 14:54:26 jonas
* (de)allocation of registers for parameters is now performed properly
(and checked on the ppc)
- removed obsolete allocation of all parameter registers at the start
of a procedure (and deallocation at the end)
Revision 1.50 2003/06/03 21:11:09 peter
* cg.a_load_* get a from and to size specifier
* makeregsize only accepts newregister
* i386 uses generic tcgnotnode,tcgunaryminus
Revision 1.49 2003/06/03 13:01:59 daniel
* Register allocator finished
Revision 1.48 2003/06/01 21:38:06 peter
* getregisterfpu size parameter added
* op_const_reg size parameter added
* sparc updates
Revision 1.47 2003/05/31 20:31:11 jonas
* set inital costs of assigning a variable to a register to 120 for
non-i386, because the used register must be store to memory at the
start and loaded again at the end
Revision 1.46 2003/05/30 18:55:21 jonas
* fixed several regvar related bugs for non-i386. make cycle with -Or now
works for ppc
Revision 1.45 2003/05/30 12:36:13 jonas
* use as little different registers on the ppc until newra is released,
since every used register must be saved
Revision 1.44 2003/05/17 13:30:08 jonas
* changed tt_persistant to tt_persistent :)
* tempcreatenode now doesn't accept a boolean anymore for persistent
temps, but a ttemptype, so you can also create ansistring temps etc
Revision 1.43 2003/05/16 14:33:31 peter
* regvar fixes
Revision 1.42 2003/04/26 20:03:49 daniel
* Bug fix in simplify
Revision 1.41 2003/04/25 20:59:35 peter
* removed funcretn,funcretsym, function result is now in varsym
and aliases for result and function name are added using absolutesym
* vs_hidden parameter for funcret passed in parameter
* vs_hidden fixes
* writenode changed to printnode and released from extdebug
* -vp option added to generate a tree.log with the nodetree
* nicer printnode for statements, callnode
Revision 1.40 2003/04/25 08:25:26 daniel
* Ifdefs around a lot of calls to cleartempgen
* Fixed registers that are allocated but not freed in several nodes
* Tweak to register allocator to cause less spills
* 8-bit registers now interfere with esi,edi and ebp
Compiler can now compile rtl successfully when using new register
allocator
Revision 1.39 2003/04/23 20:23:06 peter
* compile fix for no-newra
Revision 1.38 2003/04/23 14:42:07 daniel
* Further register allocator work. Compiler now smaller with new
allocator than without.
* Somebody forgot to adjust ppu version number
Revision 1.37 2003/04/22 23:50:23 peter
* firstpass uses expectloc
* checks if there are differences between the expectloc and
location.loc from secondpass in EXTDEBUG
Revision 1.36 2003/04/22 10:09:35 daniel
+ Implemented the actual register allocator
+ Scratch registers unavailable when new register allocator used
+ maybe_save/maybe_restore unavailable when new register allocator used
Revision 1.35 2003/04/21 19:16:49 peter
* count address regs separate
Revision 1.34 2003/04/17 16:48:21 daniel
* Added some code to keep track of move instructions in register
allocator
Revision 1.33 2003/04/17 07:50:24 daniel
* Some work on interference graph construction
Revision 1.32 2003/03/28 19:16:57 peter
* generic constructor working for i386
* remove fixed self register
* esi added as address register for i386
Revision 1.31 2003/03/11 21:46:24 jonas
* lots of new regallocator fixes, both in generic and ppc-specific code
(ppc compiler still can't compile the linux system unit though)
Revision 1.30 2003/03/09 21:18:59 olle
+ added cutils to the uses clause
Revision 1.29 2003/03/08 20:36:41 daniel
+ Added newra version of Ti386shlshrnode
+ Added interference graph construction code
Revision 1.28 2003/03/08 13:59:16 daniel
* Work to handle new register notation in ag386nsm
+ Added newra version of Ti386moddivnode
Revision 1.27 2003/03/08 10:53:48 daniel
* Created newra version of secondmul in n386add.pas
Revision 1.26 2003/03/08 08:59:07 daniel
+ $define newra will enable new register allocator
+ getregisterint will return imaginary registers with $newra
+ -sr switch added, will skip register allocation so you can see
the direct output of the code generator before register allocation
Revision 1.25 2003/02/26 20:50:45 daniel
* Fixed ungetreference
Revision 1.24 2003/02/19 22:39:56 daniel
* Fixed a few issues
Revision 1.23 2003/02/19 22:00:14 daniel
* Code generator converted to new register notation
- Horribily outdated todo.txt removed
Revision 1.22 2003/02/02 19:25:54 carl
* Several bugfixes for m68k target (register alloc., opcode emission)
+ VIS target
+ Generic add more complete (still not verified)
Revision 1.21 2003/01/08 18:43:57 daniel
* Tregister changed into a record
Revision 1.20 2002/10/05 12:43:28 carl
* fixes for Delphi 6 compilation
(warning : Some features do not work under Delphi)
Revision 1.19 2002/08/23 16:14:49 peter
* tempgen cleanup
* tt_noreuse temp type added that will be used in genentrycode
Revision 1.18 2002/08/17 22:09:47 florian
* result type handling in tcgcal.pass_2 overhauled
* better tnode.dowrite
* some ppc stuff fixed
Revision 1.17 2002/08/17 09:23:42 florian
* first part of procinfo rewrite
Revision 1.16 2002/08/06 20:55:23 florian
* first part of ppc calling conventions fix
Revision 1.15 2002/08/05 18:27:48 carl
+ more more more documentation
+ first version include/exclude (can't test though, not enough scratch for i386 :()...
Revision 1.14 2002/08/04 19:06:41 carl
+ added generic exception support (still does not work!)
+ more documentation
Revision 1.13 2002/07/07 09:52:32 florian
* powerpc target fixed, very simple units can be compiled
* some basic stuff for better callparanode handling, far from being finished
Revision 1.12 2002/07/01 18:46:26 peter
* internal linker
* reorganized aasm layer
Revision 1.11 2002/05/18 13:34:17 peter
* readded missing revisions
Revision 1.10 2002/05/16 19:46:44 carl
+ defines.inc -> fpcdefs.inc to avoid conflicts if compiling by hand
+ try to fix temp allocation (still in ifdef)
+ generic constructor calls
+ start of tassembler / tmodulebase class cleanup
Revision 1.8 2002/04/21 15:23:03 carl
+ makeregsize
+ changeregsize is now a local routine
Revision 1.7 2002/04/20 21:32:25 carl
+ generic FPC_CHECKPOINTER
+ first parameter offset in stack now portable
* rename some constants
+ move some cpu stuff to other units
- remove unused constents
* fix stacksize for some targets
* fix generic size problems which depend now on EXTEND_SIZE constant
Revision 1.6 2002/04/15 19:03:31 carl
+ reg2str -> std_reg2str()
Revision 1.5 2002/04/06 18:13:01 jonas
* several powerpc-related additions and fixes
Revision 1.4 2002/04/04 19:06:04 peter
* removed unused units
* use tlocation.size in cg.a_*loc*() routines
Revision 1.3 2002/04/02 17:11:29 peter
* tlocation,treference update
* LOC_CONSTANT added for better constant handling
* secondadd splitted in multiple routines
* location_force_reg added for loading a location to a register
of a specified size
* secondassignment parses now first the right and then the left node
(this is compatible with Kylix). This saves a lot of push/pop especially
with string operations
* adapted some routines to use the new cg methods
Revision 1.2 2002/04/01 19:24:25 jonas
* fixed different parameter name in interface and implementation
declaration of a method (only 1.0.x detected this)
Revision 1.1 2002/03/31 20:26:36 jonas
+ a_loadfpu_* and a_loadmm_* methods in tcg
* register allocation is now handled by a class and is mostly processor
independent (+rgobj.pas and i386/rgcpu.pas)
* temp allocation is now handled by a class (+tgobj.pas, -i386\tgcpu.pas)
* some small improvements and fixes to the optimizer
* some register allocation fixes
* some fpuvaroffset fixes in the unary minus node
* push/popusedregisters is now called rg.save/restoreusedregisters and
(for i386) uses temps instead of push/pop's when using -Op3 (that code is
also better optimizable)
* fixed and optimized register saving/restoring for new/dispose nodes
* LOC_FPU locations now also require their "register" field to be set to
R_ST, not R_ST0 (the latter is used for LOC_CFPUREGISTER locations only)
- list field removed of the tnode class because it's not used currently
and can cause hard-to-find bugs
}