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* avoid overflow during register allocation

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git-svn-id: trunk@49285 -
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florian 2021-04-28 18:32:48 +00:00
parent 72667f41ad
commit 837b433abc
1 changed files with 8 additions and 4 deletions
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12
compiler/rgobj.pas
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@ -2846,8 +2846,10 @@ unit rgobj;
set weigth of the newly allocated register higher than the old one, set weigth of the newly allocated register higher than the old one,
so it will selected for spilling with a lower priority than so it will selected for spilling with a lower priority than
the original one, this prevents an endless spilling loop if orgreg the original one, this prevents an endless spilling loop if orgreg
is short living, see e.g. tw25164.pp } is short living, see e.g. tw25164.pp
add_reg_instruction(instr,loadreg,reginfo[orgreg].weight+1);
the min trick is needed to avoid an overflow in case weight=high(weight which might happen }
add_reg_instruction(instr,loadreg,min(high(reginfo[orgreg].weight)-1,reginfo[orgreg].weight)+1);
ungetregisterinline(list,loadreg); ungetregisterinline(list,loadreg);
end; end;
end; end;
@ -2878,8 +2880,10 @@ unit rgobj;
set weigth of the newly allocated register higher than the old one, set weigth of the newly allocated register higher than the old one,
so it will selected for spilling with a lower priority than so it will selected for spilling with a lower priority than
the original one, this prevents an endless spilling loop if orgreg the original one, this prevents an endless spilling loop if orgreg
is short living, see e.g. tw25164.pp } is short living, see e.g. tw25164.pp
add_reg_instruction(instr,storereg,reginfo[orgreg].weight+1);
the min trick is needed to avoid an overflow in case weight=high(weight which might happen }
add_reg_instruction(instr,storereg,min(high(reginfo[orgreg].weight)-1,reginfo[orgreg].weight)+1);
end; end;
end; end;