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* insert swap instructions if it results in store/regdealloc/load

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git-svn-id: trunk@31455 -
This commit is contained in:
Jonas Maebe 2015-08-29 21:06:26 +00:00
parent 51864b0458
commit dde8e323e0
1 changed files with 67 additions and 1 deletions
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68
compiler/jvm/rgcpu.pas
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@ -201,6 +201,71 @@ implementation
end;
function try_swap_store_x_load(var p: tai): boolean;
var
insertpos,
storex,
deallocy,
loady,
deallocx,
loadx: tai;
swapxy: taicpu;
regx, regy: tregister;
begin
result:=false;
{ check for:
alloc regx (optional)
store regx (p)
dealloc regy
load regy
dealloc regx
load regx
and change to
dealloc regy
load regy
swap
alloc regx (if it existed)
store regx
dealloc regx
load regx
This will create opportunities to remove the store/load regx
(and possibly also for regy)
}
regx:=NR_NO;
regy:=NR_NO;
if not issimpleregstore(p,regx,false) then
exit;
storex:=p;
deallocy:=nextskipping(storex,[ait_comment,ait_tempalloc]);
loady:=nextskipping(deallocy,[ait_comment,ait_tempalloc]);
deallocx:=nextskipping(loady,[ait_comment,ait_tempalloc]);
loadx:=nextskipping(deallocx,[ait_comment,ait_tempalloc]);
if not assigned(loadx) then
exit;
if not issimpleregload(loady,regy,false) then
exit;
if not issimpleregload(loadx,regx,false) then
exit;
if not isregallocoftyp(deallocy,ra_dealloc,regy) then
exit;
if not isregallocoftyp(deallocx,ra_dealloc,regx) then
exit;
insertpos:=tai(p.previous);
if not assigned(insertpos) or
not isregallocoftyp(insertpos,ra_alloc,regx) then
insertpos:=storex;
list.remove(deallocy);
list.insertbefore(deallocy,insertpos);
list.remove(loady);
list.insertbefore(loady,insertpos);
swapxy:=taicpu.op_none(a_swap);
swapxy.fileinfo:=taicpu(loady).fileinfo;
list.insertbefore(swapxy,insertpos);
result:=true;
end;
var
p,next,nextnext: tai;
reg: tregister;
@ -241,7 +306,8 @@ implementation
end;
ait_instruction:
begin
if try_remove_store_dealloc_load(p) then
if try_remove_store_dealloc_load(p) or
try_swap_store_x_load(p) then
begin
removedsomething:=true;
continue;