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* more efficient temp allocation, in particular in case many small temps

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are allocated at irregular intervals in between larger allocations
    (reduces stack usage of taddnode.det_resulttype on darwin/i386 from
     11+kb to 868 bytes; no effect on Darwin/ppc, and a few small
     improvements on linux/i386)

git-svn-id: trunk@4640 -
This commit is contained in:
Jonas Maebe 2006-09-17 20:49:48 +00:00
parent 83caedf4d2
commit b50841bfce
2 changed files with 74 additions and 9 deletions
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24
compiler/cutils.pas
View File

@ -56,6 +56,7 @@ interface
function align(i,a:longint):longint;{$ifdef USEINLINE}inline;{$endif}
function used_align(varalign,minalign,maxalign:shortint):shortint;
function isbetteralignedthan(new, org, limit: cardinal): boolean;
function size_2_align(len : longint) : shortint;
function packedbitsloadsize(bitlen: int64) : int64;
procedure Replace(var s:string;s1:string;const s2:string);
@ -292,6 +293,29 @@ uses
end;
function isbetteralignedthan(new, org, limit: cardinal): boolean;
var
cnt: cardinal;
begin
cnt:=2;
while (cnt <= limit) do
begin
if (org and (cnt-1)) > (new and (cnt-1)) then
begin
result:=true;
exit;
end
else if (org and (cnt-1)) < (new and (cnt-1)) then
begin
result:=false;
exit;
end;
cnt:=cnt*2;
end;
result:=false;
end;
function used_align(varalign,minalign,maxalign:shortint):shortint;
begin
{ varalign : minimum alignment required for the variable

59
compiler/tgobj.pas
View File

@ -218,14 +218,16 @@ implementation
tl,htl,
bestslot,bestprev,
hprev,hp : ptemprecord;
bestsize : longint;
freetype : ttemptype;
bestatend,
fitatbegin,
fitatend : boolean;
begin
AllocTemp:=0;
bestprev:=nil;
bestslot:=nil;
tl:=nil;
bestsize:=0;
bestatend:=false;
if size=0 then
begin
@ -260,23 +262,56 @@ implementation
if (hp^.temptype=freetype) and
(hp^.def=def) and
(hp^.size>=size) and
(hp^.pos=align(hp^.pos,alignment)) then
((hp^.pos=align(hp^.pos,alignment)) or
(hp^.pos+hp^.size-size = align(hp^.pos+hp^.size-size,alignment))) then
begin
{ Slot is the same size then leave immediatly }
if (hp^.size=size) then
begin
bestprev:=hprev;
bestslot:=hp;
bestsize:=size;
break;
end
else
begin
if (bestsize=0) or (hp^.size<bestsize) then
{ we can fit a smaller block either at the begin or at }
{ the end of a block. For direction=-1 we prefer the }
{ end, for direction=1 we prefer the begin (i.e., }
{ always closest to the source). We also try to use }
{ the block with the worst possible alignment that }
{ still suffices. And we pick the block which will }
{ have the best alignmenment after this new block is }
{ substracted from it. }
fitatend:=(hp^.pos+hp^.size-size)=align(hp^.pos+hp^.size-size,alignment);
fitatbegin:=hp^.pos=align(hp^.pos,alignment);
if assigned(bestslot) then
begin
fitatend:=fitatend and
((not bestatend and
(direction=-1)) or
(bestatend and
isbetteralignedthan(abs(bestslot^.pos+hp^.size-size),abs(hp^.pos+hp^.size-size),aktalignment.localalignmax)));
fitatbegin:=fitatbegin and
(not bestatend or
(direction=1)) and
isbetteralignedthan(abs(hp^.pos+size),abs(bestslot^.pos+size),aktalignment.localalignmax);
end;
if fitatend and
fitatbegin then
if isbetteralignedthan(abs(hp^.pos+hp^.size-size),abs(hp^.pos+size),aktalignment.localalignmax) then
fitatbegin:=false
else if isbetteralignedthan(abs(hp^.pos+size),abs(hp^.pos+hp^.size-size),aktalignment.localalignmax) then
fitatend:=false
else if (direction=1) then
fitatend:=false
else
fitatbegin:=false;
if fitatend or
fitatbegin then
begin
bestprev:=hprev;
bestslot:=hp;
bestsize:=hp^.size;
bestatend:=fitatend;
end;
end;
end;
@ -287,7 +322,7 @@ implementation
{ Reuse an old temp ? }
if assigned(bestslot) then
begin
if bestsize=size then
if bestslot^.size=size then
begin
tl:=bestslot;
{ Remove from the tempfreelist }
@ -308,7 +343,8 @@ implementation
For direction=1 we can use tl for the new block. For direction=-1 we
will be reusing bestslot and resize the new block, that means we need
to swap the pointers }
if direction=-1 then
if (direction=-1) xor
bestatend then
begin
htl:=tl;
tl:=bestslot;
@ -319,12 +355,17 @@ implementation
else
tempfreelist:=bestslot;
end;
if not bestatend then
inc(bestslot^.pos,size)
else
inc(tl^.pos,tl^.size-size);
{ Create new block and resize the old block }
tl^.size:=size;
tl^.nextfree:=nil;
{ Resize the old block }
dec(bestslot^.size,size);
inc(bestslot^.pos,size);
end;
tl^.temptype:=temptype;
tl^.def:=def;