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* patch by Nico Erfurth: Remove superfluous mov from MovStrMov sequences

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git-svn-id: trunk@21067 -
This commit is contained in:
florian 2012-04-26 20:31:13 +00:00
parent a26bc50ca6
commit 2959d596f9
1 changed files with 38 additions and 0 deletions
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38
compiler/arm/aoptcpu.pas
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@ -87,6 +87,16 @@ Implementation
((postfix = []) or (taicpu(instr).oppostfix in postfix));
end;
function MatchOperand(const oper1: TOper; const oper2: TOper): boolean; inline;
begin
result := (oper1.typ = oper2.typ) and
(
((oper1.typ = top_const) and (oper1.val = oper2.val)) or
((oper1.typ = top_reg) and (oper1.reg = oper2.reg)) or
((oper1.typ = top_conditioncode) and (oper1.cc = oper2.cc))
);
end;
function MatchOperand(const oper: TOper; const reg: TRegister): boolean; inline;
begin
result := (oper.typ = top_reg) and (oper.reg = reg);
@ -253,6 +263,34 @@ Implementation
result := true;
end;
{
This changes the very common
mov r0, #0
str r0, [...]
mov r0, #0
str r0, [...]
and removes all superfluous mov instructions
}
if (taicpu(p).ops = 2) and
(taicpu(p).oper[1]^.typ = top_const) and
GetNextInstruction(p,hp1) then
begin
while MatchInstruction(hp1, A_STR, [], []) and
MatchOperand(taicpu(hp1).oper[0]^, taicpu(p).oper[0]^) and
GetNextInstruction(hp1, hp2) and
MatchInstruction(hp2, A_MOV, [taicpu(p).condition], [taicpu(p).oppostfix]) and
(taicpu(hp2).ops = 2) and
MatchOperand(taicpu(hp2).oper[0]^, taicpu(p).oper[0]^) and
MatchOperand(taicpu(hp2).oper[1]^, taicpu(p).oper[1]^) do
begin
asml.insertbefore(tai_comment.Create(strpnew('Peephole MovStrMov done')), hp2);
GetNextInstruction(hp2,hp1);
asml.remove(hp2);
hp2.free;
if not assigned(hp1) then break;
end;
end;
{
change
mov r1, r0