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New MovxAndTest2Test optimisation to mirror the regular MovAndTest2Test optimisation

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J. Gareth "Curious Kit" Moreton 2021-12-07 18:37:21 +00:00 committed by FPK
parent 5b4c104aaf
commit d083cc7247
1 changed files with 78 additions and 2 deletions
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80
compiler/x86/aoptx86.pas
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@ -10017,7 +10017,7 @@ movzx_cascade:
function TX86AsmOptimizer.OptPass1Movx(var p : tai) : boolean;
var
hp1,hp2: tai;
hp1,hp2,hp3: tai;
reg_and_hp1_is_instr, RegUsed, AndTest: Boolean;
NewSize: TOpSize;
NewRegSize: TSubRegister;
@ -10161,7 +10161,15 @@ movzx_cascade:
(
(
(taicpu(hp2).opcode=A_TEST) and
MatchOperand(taicpu(hp2).oper[0]^, taicpu(hp1).oper[1]^.reg) and
(
MatchOperand(taicpu(hp2).oper[0]^, taicpu(hp1).oper[1]^.reg) or
MatchOperand(taicpu(hp2).oper[0]^, -1) or
(
{ If the AND and TEST instructions share a constant, this is also valid }
(taicpu(hp1).oper[0]^.typ = top_const) and
MatchOperand(taicpu(hp2).oper[0]^, taicpu(hp1).oper[0]^.val)
)
) and
MatchOperand(taicpu(hp2).oper[1]^, taicpu(hp1).oper[1]^.reg)
) or
(
@ -10171,6 +10179,74 @@ movzx_cascade:
)
);
{ change
movx (oper),%reg2
and $x,%reg2
test %reg2,%reg2
dealloc %reg2
into
op %reg1,%reg3
if the second op accesses only the bits stored in reg1
}
if ((taicpu(p).oper[0]^.typ=top_reg) or
((taicpu(p).oper[0]^.typ=top_ref) and (taicpu(p).oper[0]^.ref^.refaddr<>addr_full))) and
(taicpu(hp1).oper[0]^.typ = top_const) and
(taicpu(hp1).oper[1]^.reg = taicpu(p).oper[1]^.reg) and
AndTest then
begin
{ Check if the AND constant is in range }
case taicpu(p).opsize of
S_BW, S_BL{$ifdef x86_64}, S_BQ{$endif x86_64}:
begin
NewSize := S_B;
Limit := $FF;
end;
S_WL{$ifdef x86_64}, S_WQ{$endif x86_64}:
begin
NewSize := S_W;
Limit := $FFFF;
end;
{$ifdef x86_64}
S_LQ:
begin
NewSize := S_L;
Limit := $FFFFFFFF;
end;
{$endif x86_64}
else
InternalError(2021120303);
end;
if (
((taicpu(hp1).oper[0]^.val and Limit) = taicpu(hp1).oper[0]^.val) or
{ Check for negative operands }
(((not taicpu(hp1).oper[0]^.val) and Limit) = (not taicpu(hp1).oper[0]^.val))
) and
GetNextInstruction(hp2,hp3) and
MatchInstruction(hp3,A_Jcc,A_Setcc,A_CMOVcc,[]) and
(taicpu(hp3).condition in [C_E,C_NE]) then
begin
TransferUsedRegs(TmpUsedRegs);
UpdateUsedRegs(TmpUsedRegs, tai(p.Next));
UpdateUsedRegs(TmpUsedRegs, tai(hp1.Next));
if not(RegUsedAfterInstruction(taicpu(hp2).oper[1]^.reg, hp2, TmpUsedRegs)) then
begin
DebugMsg(SPeepholeOptimization + 'MovxAndTest2Test done',p);
taicpu(hp1).loadoper(1, taicpu(p).oper[0]^);
taicpu(hp1).opcode := A_TEST;
taicpu(hp1).opsize := NewSize;
RemoveInstruction(hp2);
RemoveCurrentP(p, hp1);
Result:=true;
exit;
end;
end;
end;
if (taicpu(hp1).oper[0]^.typ = top_reg) and
(((taicpu(p).opsize in [S_BW,S_BL,S_WL{$ifdef x86_64},S_BQ,S_WQ,S_LQ{$endif x86_64}]) and
(taicpu(hp1).opsize=S_B)) or