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* x86: Fix to MOV/CMP register deallocation positioning

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J. Gareth "Curious Kit" Moreton 2022-02-24 22:30:54 +00:00 committed by Pierre Muller
parent 42472aac89
commit 2d5ef5b5d0
1 changed files with 24 additions and 8 deletions
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32
compiler/x86/aoptx86.pas
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@ -153,7 +153,7 @@ unit aoptx86;
procedure RemoveLastDeallocForFuncRes(p : tai);
function DoArithCombineOpt(var p : tai) : Boolean;
function DoMovCmpMemOpt(var p : tai; const hp1: tai; UpdateTmpUsedRegs: Boolean) : Boolean;
function DoMovCmpMemOpt(var p : tai; const hp1: tai) : Boolean;
function DoSETccLblRETOpt(var p: tai; const hp_label: tai_label) : Boolean;
function PrePeepholeOptSxx(var p : tai) : boolean;
@ -4632,7 +4632,7 @@ unit aoptx86;
Exit;
end;
if DoMovCmpMemOpt(p, hp1, True) then
if DoMovCmpMemOpt(p, hp1) then
begin
Result := True;
Exit;
@ -6244,12 +6244,11 @@ unit aoptx86;
end;
function TX86AsmOptimizer.DoMovCmpMemOpt(var p : tai; const hp1: tai; UpdateTmpUsedRegs: Boolean) : Boolean;
function TX86AsmOptimizer.DoMovCmpMemOpt(var p : tai; const hp1: tai) : Boolean;
var
hp2: tai;
begin
Result := False;
if UpdateTmpUsedRegs then
TransferUsedRegs(TmpUsedRegs);
if MatchOpType(taicpu(p),top_ref,top_reg) and
{ The x86 assemblers have difficulty comparing values against absolute addresses }
(taicpu(p).oper[0]^.ref^.refaddr <> addr_full) and
@ -6267,6 +6266,7 @@ unit aoptx86;
begin
{ change
mov mem, %reg
...
cmp/test x, %reg / test %reg,%reg
(reg deallocated)
@ -6274,6 +6274,7 @@ unit aoptx86;
cmp/test x, mem / cmp 0, mem
}
TransferUsedRegs(TmpUsedRegs);
UpdateUsedRegs(TmpUsedRegs, tai(p.Next));
if not RegUsedAfterInstruction(taicpu(p).oper[1]^.reg, hp1, TmpUsedRegs) then
begin
@ -6289,7 +6290,22 @@ unit aoptx86;
end;
taicpu(hp1).loadref(1, taicpu(p).oper[0]^.ref^);
DebugMsg(SPeepholeOptimization + 'MOV/CMP -> CMP (memory check)', p);
RemoveCurrentP(p, hp1);
RemoveCurrentP(p);
if (p <> hp1) then
begin
{ Correctly update TmpUsedRegs if p and hp1 aren't adjacent }
hp2 := p;
repeat
UpdateUsedRegs(TmpUsedRegs, tai(hp2.Next));
until not GetNextInstruction(hp2, hp2) or (hp2 = hp1);
end;
{ Make sure the flags are allocated across the CMP instruction }
if not RegInUsedRegs(NR_DEFAULTFLAGS, TmpUsedRegs) then
AllocRegBetween(NR_DEFAULTFLAGS, hp1, hp1, TmpUsedRegs);
Result := True;
Exit;
end;
@ -9313,7 +9329,7 @@ unit aoptx86;
Exit;
if MatchInstruction(hp1, A_CMP, A_TEST, [taicpu(p).opsize])
and DoMovCmpMemOpt(p, hp1, True) then
and DoMovCmpMemOpt(p, hp1) then
begin
Result := True;
Exit;