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* i386: more clean up of TCPUAsmOPtimizer.PeepHoleOptPass1Cpu

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git-svn-id: trunk@43465 -
This commit is contained in:
florian 2019-11-14 21:26:48 +00:00
parent 632f13c47a
commit 87b3b089d6
1 changed files with 221 additions and 301 deletions
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84
compiler/i386/aoptcpu.pas
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@ -245,85 +245,6 @@ unit aoptcpu;
Result:=true; Result:=true;
exit; exit;
end; end;
{ Handle Jmp Optimizations }
if taicpu(p).is_jmp then
begin
{ the following if-block removes all code between a jmp and the next label,
because it can never be executed }
if (taicpu(p).opcode = A_JMP) then
begin
hp2:=p;
while GetNextInstruction(hp2, hp1) and
(hp1.typ <> ait_label) do
if not(hp1.typ in ([ait_label]+skipinstr)) then
begin
{ don't kill start/end of assembler block,
no-line-info-start/end, cfi end, etc }
if not(hp1.typ in [ait_align,ait_marker]) and
((hp1.typ<>ait_cfi) or
(tai_cfi_base(hp1).cfityp<>cfi_endproc)) then
begin
asml.remove(hp1);
hp1.free;
end
else
hp2:=hp1;
end
else break;
end;
{ remove jumps to a label coming right after them }
if GetNextInstruction(p, hp1) then
begin
if FindLabel(tasmlabel(taicpu(p).oper[0]^.ref^.symbol), hp1) and
{ TODO: FIXME removing the first instruction fails}
(p<>blockstart) then
begin
hp2:=tai(hp1.next);
asml.remove(p);
p.free;
p:=hp2;
Result:=true;
exit;
end
else
begin
if hp1.typ = ait_label then
SkipLabels(hp1,hp1);
if (tai(hp1).typ=ait_instruction) and
(taicpu(hp1).opcode=A_JMP) and
GetNextInstruction(hp1, hp2) and
FindLabel(tasmlabel(taicpu(p).oper[0]^.ref^.symbol), hp2) then
begin
if taicpu(p).opcode=A_Jcc then
begin
taicpu(p).condition:=inverse_cond(taicpu(p).condition);
tai_label(hp2).labsym.decrefs;
taicpu(p).oper[0]^.ref^.symbol:=taicpu(hp1).oper[0]^.ref^.symbol;
{ when free'ing hp1, the ref. isn't decresed, so we don't
increase it (FK)
taicpu(p).oper[0]^.ref^.symbol.increfs;
}
asml.remove(hp1);
hp1.free;
GetFinalDestination(asml, taicpu(p),0);
end
else
begin
GetFinalDestination(asml, taicpu(p),0);
p:=tai(p.next);
Result:=true;
exit;
end;
end
else
GetFinalDestination(asml, taicpu(p),0);
end;
end;
end
else
{ All other optimizes }
begin
case taicpu(p).opcode Of case taicpu(p).opcode Of
A_AND: A_AND:
Result:=OptPass1And(p); Result:=OptPass1And(p);
@ -417,7 +338,7 @@ unit aoptcpu;
A_MOVSX, A_MOVSX,
A_MOVZX : A_MOVZX :
Result:=OptPass1Movx(p); Result:=OptPass1Movx(p);
(* should not be generated anymore by the current code generator (* should not be generated anymore by the current code generator
A_POP: A_POP:
begin begin
if target_info.system=system_i386_go32v2 then if target_info.system=system_i386_go32v2 then
@ -501,7 +422,7 @@ unit aoptcpu;
end; end;
end; end;
end; end;
*) *)
A_PUSH: A_PUSH:
begin begin
if (taicpu(p).opsize = S_W) and if (taicpu(p).opsize = S_W) and
@ -562,7 +483,6 @@ unit aoptcpu;
else else
; ;
end; end;
end; { if is_jmp }
end; end;
else else
; ;