paweld/fpc
1
0
Fork 0
mirror of https://gitlab.com/freepascal.org/fpc/source.git synced 2025-09-01 23:50:23 +02:00
Code Issues Packages Projects Releases Wiki Activity

* don't remove regalloc/regdealloc pair if it's immediately followed by a

Browse Source 
use of the register (can happen if the register is unused afterwards;
    remove the alloc/dealloc results in no temp being allocated for the
    register, so that instruction becomes invalid)

git-svn-id: branches/jvmbackend@18455 -
This commit is contained in:
Jonas Maebe 2011-08-20 08:01:19 +00:00
parent da064b0ad6
commit a5af71a8d8
1 changed files with 49 additions and 15 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

64
compiler/jvm/rgcpu.pas
View File

@ -139,6 +139,34 @@ implementation
result:=tai_regalloc(p).reg=reg;
end;
function regininstruction(p: tai; reg: tregister): boolean;
var
sr: tsuperregister;
i: longint;
begin
result:=false;
if p.typ<>ait_instruction then
exit;
sr:=getsupreg(reg);
for i:=0 to taicpu(p).ops-1 do
case taicpu(p).oper[0]^.typ of
top_reg:
if (getsupreg(taicpu(p).oper[0]^.reg)=sr) then
exit(true);
top_ref:
begin
if (getsupreg(taicpu(p).oper[0]^.ref^.base)=sr) then
exit(true);
if (getsupreg(taicpu(p).oper[0]^.ref^.index)=sr) then
exit(true);
if (getsupreg(taicpu(p).oper[0]^.ref^.indexbase)=sr) then
exit(true);
if (getsupreg(taicpu(p).oper[0]^.ref^.indexbase)=sr) then
exit(true);
end;
end;
end;
function try_remove_store_dealloc_load(var p: tai): boolean;
var
dealloc,
@ -174,7 +202,7 @@ implementation
var
p,next: tai;
p,next,nextnext: tai;
reg: tregister;
removedsomething: boolean;
begin
@ -188,21 +216,27 @@ implementation
begin
reg:=NR_NO;
next:=nextskipping(p,[ait_comment]);
{ remove
alloc reg
dealloc reg
(can appear after optimisations, necessary to prevent
useless stack slot allocations) }
if isregallocoftyp(p,ra_alloc,reg) and
isregallocoftyp(next,ra_dealloc,reg) then
nextnext:=nextskipping(next,[ait_comment,ait_regalloc]);
if assigned(nextnext) then
begin
list.remove(p);
p.free;
p:=tai(next.next);
list.remove(next);
next.free;
removedsomething:=true;
continue;
{ remove
alloc reg
dealloc reg
(can appear after optimisations, necessary to prevent
useless stack slot allocations) }
if isregallocoftyp(p,ra_alloc,reg) and
isregallocoftyp(next,ra_dealloc,reg) and
not regininstruction(nextnext,reg) then
begin
list.remove(p);
p.free;
p:=tai(next.next);
list.remove(next);
next.free;
removedsomething:=true;
continue;
end;
end;
end;
ait_instruction: