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9e039936bf
Now we can also fold shifts into teq, tst, cmp, cmn instructions. git-svn-id: trunk@22023 -
1147 lines
53 KiB
ObjectPascal
1147 lines
53 KiB
ObjectPascal
{
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Copyright (c) 1998-2002 by Jonas Maebe, member of the Free Pascal
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Development Team
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This unit implements the ARM optimizer object
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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****************************************************************************
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}
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Unit aoptcpu;
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{$i fpcdefs.inc}
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Interface
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uses cgbase, cpubase, aasmtai, aopt, aoptcpub, aoptobj;
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Type
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{ TCpuAsmOptimizer }
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TCpuAsmOptimizer = class(TAsmOptimizer)
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{ uses the same constructor as TAopObj }
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function PeepHoleOptPass1Cpu(var p: tai): boolean; override;
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procedure PeepHoleOptPass2;override;
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Function RegInInstruction(Reg: TRegister; p1: tai): Boolean;override;
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procedure RemoveSuperfluousMove(const p: tai; movp: tai; const optimizer: string);
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function RegUsedAfterInstruction(reg: Tregister; p: tai;
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var AllUsedRegs: TAllUsedRegs): Boolean;
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End;
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TCpuPreRegallocScheduler = class(TAsmOptimizer)
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function PeepHoleOptPass1Cpu(var p: tai): boolean;override;
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end;
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TCpuThumb2AsmOptimizer = class(TCpuAsmOptimizer)
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{ uses the same constructor as TAopObj }
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procedure PeepHoleOptPass2;override;
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End;
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Implementation
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uses
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cutils,
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verbose,
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cgutils,
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aasmbase,aasmdata,aasmcpu;
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function CanBeCond(p : tai) : boolean;
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begin
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result:=
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(p.typ=ait_instruction) and
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(taicpu(p).condition=C_None) and
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(taicpu(p).opcode<>A_PLD) and
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((taicpu(p).opcode<>A_BLX) or
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(taicpu(p).oper[0]^.typ=top_reg));
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end;
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function RefsEqual(const r1, r2: treference): boolean;
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begin
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refsequal :=
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(r1.offset = r2.offset) and
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(r1.base = r2.base) and
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(r1.index = r2.index) and (r1.scalefactor = r2.scalefactor) and
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(r1.symbol=r2.symbol) and (r1.refaddr = r2.refaddr) and
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(r1.relsymbol = r2.relsymbol) and
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(r1.signindex = r2.signindex) and
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(r1.shiftimm = r2.shiftimm) and
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(r1.addressmode = r2.addressmode) and
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(r1.shiftmode = r2.shiftmode);
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end;
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function MatchInstruction(const instr: tai; const op: TAsmOp; const cond: TAsmConds; const postfix: TOpPostfixes): boolean;
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begin
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result :=
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(instr.typ = ait_instruction) and
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(taicpu(instr).opcode = op) and
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((cond = []) or (taicpu(instr).condition in cond)) and
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((postfix = []) or (taicpu(instr).oppostfix in postfix));
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end;
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function MatchOperand(const oper1: TOper; const oper2: TOper): boolean; inline;
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begin
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result := oper1.typ = oper2.typ;
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if result then
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case oper1.typ of
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top_const:
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Result:=oper1.val = oper2.val;
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top_reg:
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Result:=oper1.reg = oper2.reg;
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top_conditioncode:
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Result:=oper1.cc = oper2.cc;
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top_ref:
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Result:=RefsEqual(oper1.ref^, oper2.ref^);
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else Result:=false;
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end
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end;
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function MatchOperand(const oper: TOper; const reg: TRegister): boolean; inline;
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begin
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result := (oper.typ = top_reg) and (oper.reg = reg);
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end;
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procedure RemoveRedundantMove(const cmpp: tai; movp: tai; asml: TAsmList);
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begin
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if (taicpu(movp).condition = C_EQ) and
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(taicpu(cmpp).oper[0]^.reg = taicpu(movp).oper[0]^.reg) and
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(taicpu(cmpp).oper[1]^.val = taicpu(movp).oper[1]^.val) then
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begin
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asml.insertafter(tai_comment.Create(strpnew('Peephole CmpMovMov - Removed redundant moveq')), movp);
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asml.remove(movp);
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movp.free;
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end;
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end;
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function regLoadedWithNewValue(reg: tregister; hp: tai): boolean;
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var
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p: taicpu;
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begin
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p := taicpu(hp);
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regLoadedWithNewValue := false;
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if not ((assigned(hp)) and (hp.typ = ait_instruction)) then
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exit;
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case p.opcode of
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{ These operands do not write into a register at all }
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A_CMP, A_CMN, A_TST, A_TEQ, A_B, A_BL, A_BX, A_BLX, A_SWI, A_MSR, A_PLD:
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exit;
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{Take care of post/preincremented store and loads, they will change their base register}
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A_STR, A_LDR:
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regLoadedWithNewValue :=
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(taicpu(p).oper[1]^.typ=top_ref) and
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(taicpu(p).oper[1]^.ref^.addressmode in [AM_PREINDEXED,AM_POSTINDEXED]) and
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(taicpu(p).oper[1]^.ref^.base = reg);
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{ These four are writing into the first 2 register, UMLAL and SMLAL will also read from them }
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A_UMLAL, A_UMULL, A_SMLAL, A_SMULL:
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regLoadedWithNewValue :=
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(p.oper[1]^.typ = top_reg) and
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(p.oper[1]^.reg = reg);
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{Loads to oper2 from coprocessor}
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{
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MCR/MRC is currently not supported in FPC
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A_MRC:
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regLoadedWithNewValue :=
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(p.oper[2]^.typ = top_reg) and
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(p.oper[2]^.reg = reg);
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}
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{Loads to all register in the registerset}
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A_LDM:
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regLoadedWithNewValue := (getsupreg(reg) in p.oper[1]^.regset^);
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end;
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if regLoadedWithNewValue then
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exit;
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case p.oper[0]^.typ of
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{This is the case}
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top_reg:
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regLoadedWithNewValue := (p.oper[0]^.reg = reg);
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{LDM/STM might write a new value to their index register}
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top_ref:
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regLoadedWithNewValue :=
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(taicpu(p).oper[0]^.ref^.addressmode in [AM_PREINDEXED,AM_POSTINDEXED]) and
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(taicpu(p).oper[0]^.ref^.base = reg);
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end;
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end;
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function instructionLoadsFromReg(const reg: TRegister; const hp: tai): boolean;
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var
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p: taicpu;
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i: longint;
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begin
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instructionLoadsFromReg := false;
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if not (assigned(hp) and (hp.typ = ait_instruction)) then
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exit;
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p:=taicpu(hp);
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i:=1;
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{For these instructions we have to start on oper[0]}
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if (p.opcode in [A_STR, A_LDM, A_STM, A_PLD,
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A_CMP, A_CMN, A_TST, A_TEQ,
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A_B, A_BL, A_BX, A_BLX,
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A_SMLAL, A_UMLAL]) then i:=0;
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while(i<p.ops) do
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begin
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case p.oper[I]^.typ of
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top_reg:
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instructionLoadsFromReg := p.oper[I]^.reg = reg;
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top_regset:
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instructionLoadsFromReg := (getsupreg(reg) in p.oper[I]^.regset^);
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top_shifterop:
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instructionLoadsFromReg := p.oper[I]^.shifterop^.rs = reg;
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top_ref:
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instructionLoadsFromReg :=
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(p.oper[I]^.ref^.base = reg) or
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(p.oper[I]^.ref^.index = reg);
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end;
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if instructionLoadsFromReg then exit; {Bailout if we found something}
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Inc(I);
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end;
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end;
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function TCpuAsmOptimizer.RegUsedAfterInstruction(reg: Tregister; p: tai;
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var AllUsedRegs: TAllUsedRegs): Boolean;
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begin
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AllUsedRegs[getregtype(reg)].Update(tai(p.Next));
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RegUsedAfterInstruction :=
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AllUsedRegs[getregtype(reg)].IsUsed(reg) and
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not(regLoadedWithNewValue(reg,p)) and
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(
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not(GetNextInstruction(p,p)) or
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instructionLoadsFromReg(reg,p) or
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not(regLoadedWithNewValue(reg,p))
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);
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end;
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procedure TCpuAsmOptimizer.RemoveSuperfluousMove(const p: tai; movp: tai; const optimizer: string);
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var
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TmpUsedRegs: TAllUsedRegs;
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begin
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if MatchInstruction(movp, A_MOV, [taicpu(p).condition], [PF_None]) and
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(taicpu(movp).ops=2) and {We can't optimize if there is a shiftop}
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MatchOperand(taicpu(movp).oper[1]^, taicpu(p).oper[0]^.reg) and
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{There is a special requirement for MUL and MLA, oper[0] and oper[1] are not allowed to be the same}
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not (
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(taicpu(p).opcode in [A_MLA, A_MUL]) and
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(taicpu(p).oper[1]^.reg = taicpu(movp).oper[0]^.reg)
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) then
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begin
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CopyUsedRegs(TmpUsedRegs);
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UpdateUsedRegs(TmpUsedRegs, tai(p.next));
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if not(RegUsedAfterInstruction(taicpu(p).oper[0]^.reg,movp,TmpUsedRegs)) then
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begin
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asml.insertbefore(tai_comment.Create(strpnew('Peephole '+optimizer+' removed superfluous mov')), movp);
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taicpu(p).loadreg(0,taicpu(movp).oper[0]^.reg);
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asml.remove(movp);
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movp.free;
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end;
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ReleaseUsedRegs(TmpUsedRegs);
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end;
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end;
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function TCpuAsmOptimizer.PeepHoleOptPass1Cpu(var p: tai): boolean;
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var
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hp1,hp2: tai;
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i, i2: longint;
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TmpUsedRegs: TAllUsedRegs;
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tempop: tasmop;
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function IsPowerOf2(const value: DWord): boolean; inline;
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begin
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Result:=(value and (value - 1)) = 0;
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end;
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begin
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result := false;
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case p.typ of
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ait_instruction:
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begin
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(* optimization proved not to be safe, see tw4768.pp
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{
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change
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<op> reg,x,y
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cmp reg,#0
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into
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<op>s reg,x,y
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}
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{ this optimization can applied only to the currently enabled operations because
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the other operations do not update all flags and FPC does not track flag usage }
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if (taicpu(p).opcode in [A_ADC,A_ADD,A_SUB {A_UDIV,A_SDIV,A_MUL,A_MVN,A_MOV,A_ORR,A_EOR,A_AND}]) and
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(taicpu(p).oppostfix = PF_None) and
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(taicpu(p).condition = C_None) and
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GetNextInstruction(p, hp1) and
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MatchInstruction(hp1, A_CMP, [C_None], [PF_None]) and
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(taicpu(hp1).oper[1]^.typ = top_const) and
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(taicpu(p).oper[0]^.reg = taicpu(hp1).oper[0]^.reg) and
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(taicpu(hp1).oper[1]^.val = 0) { and
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GetNextInstruction(hp1, hp2) and
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(tai(hp2).typ = ait_instruction) and
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// be careful here, following instructions could use other flags
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// however after a jump fpc never depends on the value of flags
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(taicpu(hp2).opcode = A_B) and
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(taicpu(hp2).condition in [C_EQ,C_NE,C_MI,C_PL])} then
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begin
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taicpu(p).oppostfix:=PF_S;
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asml.remove(hp1);
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hp1.free;
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end
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else
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*)
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case taicpu(p).opcode of
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A_STR:
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begin
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{ change
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str reg1,ref
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ldr reg2,ref
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into
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str reg1,ref
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mov reg2,reg1
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}
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if (taicpu(p).oper[1]^.ref^.addressmode=AM_OFFSET) and
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(taicpu(p).oppostfix=PF_None) and
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GetNextInstruction(p,hp1) and
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MatchInstruction(hp1, A_LDR, [taicpu(p).condition, C_None], [PF_None]) and
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RefsEqual(taicpu(p).oper[1]^.ref^,taicpu(hp1).oper[1]^.ref^) and
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(taicpu(hp1).oper[1]^.ref^.addressmode=AM_OFFSET) then
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begin
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if taicpu(hp1).oper[0]^.reg=taicpu(p).oper[0]^.reg then
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begin
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asml.insertbefore(tai_comment.Create(strpnew('Peephole StrLdr2StrMov 1 done')), hp1);
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asml.remove(hp1);
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hp1.free;
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end
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else
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begin
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taicpu(hp1).opcode:=A_MOV;
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taicpu(hp1).oppostfix:=PF_None;
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taicpu(hp1).loadreg(1,taicpu(p).oper[0]^.reg);
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asml.insertbefore(tai_comment.Create(strpnew('Peephole StrLdr2StrMov 2 done')), hp1);
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end;
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result := true;
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end;
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end;
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A_LDR:
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begin
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{ change
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ldr reg1,ref
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ldr reg2,ref
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into
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ldr reg1,ref
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mov reg2,reg1
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}
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if (taicpu(p).oper[1]^.ref^.addressmode=AM_OFFSET) and
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GetNextInstruction(p,hp1) and
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MatchInstruction(hp1, A_LDR, [taicpu(p).condition, C_None], [taicpu(p).oppostfix]) and
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RefsEqual(taicpu(p).oper[1]^.ref^,taicpu(hp1).oper[1]^.ref^) and
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(taicpu(p).oper[0]^.reg<>taicpu(hp1).oper[1]^.ref^.index) and
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(taicpu(p).oper[0]^.reg<>taicpu(hp1).oper[1]^.ref^.base) and
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(taicpu(hp1).oper[1]^.ref^.addressmode=AM_OFFSET) then
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begin
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if taicpu(hp1).oper[0]^.reg=taicpu(p).oper[0]^.reg then
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begin
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asml.insertbefore(tai_comment.Create(strpnew('Peephole LdrLdr2Ldr done')), hp1);
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asml.remove(hp1);
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hp1.free;
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end
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else
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begin
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asml.insertbefore(tai_comment.Create(strpnew('Peephole LdrLdr2LdrMov done')), hp1);
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taicpu(hp1).opcode:=A_MOV;
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taicpu(hp1).oppostfix:=PF_None;
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taicpu(hp1).loadreg(1,taicpu(p).oper[0]^.reg);
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end;
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result := true;
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end;
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{ Remove superfluous mov after ldr
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changes
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ldr reg1, ref
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mov reg2, reg1
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to
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ldr reg2, ref
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conditions are:
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* reg1 must be released after mov
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* mov can not contain shifterops
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* ldr+mov have the same conditions
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* mov does not set flags
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}
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if GetNextInstruction(p, hp1) then
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RemoveSuperfluousMove(p, hp1, 'LdrMov2Ldr');
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end;
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A_MOV:
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begin
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{ fold
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mov reg1,reg0, shift imm1
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mov reg1,reg1, shift imm2
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}
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if (taicpu(p).ops=3) and
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(taicpu(p).oper[2]^.typ = top_shifterop) and
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(taicpu(p).oper[2]^.shifterop^.rs = NR_NO) and
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getnextinstruction(p,hp1) and
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MatchInstruction(hp1, A_MOV, [taicpu(p).condition], [PF_None]) and
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(taicpu(hp1).ops=3) and
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MatchOperand(taicpu(hp1).oper[0]^, taicpu(p).oper[0]^.reg) and
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MatchOperand(taicpu(hp1).oper[1]^, taicpu(p).oper[0]^.reg) and
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(taicpu(hp1).oper[2]^.typ = top_shifterop) and
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(taicpu(hp1).oper[2]^.shifterop^.rs = NR_NO) then
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begin
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{ fold
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mov reg1,reg0, lsl 16
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mov reg1,reg1, lsr 16
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strh reg1, ...
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dealloc reg1
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to
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strh reg1, ...
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dealloc reg1
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}
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if (taicpu(p).oper[2]^.shifterop^.shiftmode=SM_LSL) and
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(taicpu(p).oper[2]^.shifterop^.shiftimm=16) and
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(taicpu(hp1).oper[2]^.shifterop^.shiftmode in [SM_LSR,SM_ASR]) and
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(taicpu(hp1).oper[2]^.shifterop^.shiftimm=16) and
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getnextinstruction(hp1,hp2) and
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MatchInstruction(hp2, A_STR, [taicpu(p).condition], [PF_H]) and
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MatchOperand(taicpu(hp2).oper[0]^, taicpu(p).oper[0]^.reg) then
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begin
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CopyUsedRegs(TmpUsedRegs);
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UpdateUsedRegs(TmpUsedRegs, tai(p.next));
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UpdateUsedRegs(TmpUsedRegs, tai(hp1.next));
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if not(RegUsedAfterInstruction(taicpu(p).oper[0]^.reg,hp2,TmpUsedRegs)) then
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begin
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asml.insertbefore(tai_comment.Create(strpnew('Peephole optimizer removed superfluous 16 Bit zero extension')), hp1);
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taicpu(hp2).loadreg(0,taicpu(p).oper[1]^.reg);
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asml.remove(p);
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asml.remove(hp1);
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p.free;
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hp1.free;
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p:=hp2;
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end;
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ReleaseUsedRegs(TmpUsedRegs);
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end
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{ fold
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mov reg1,reg0, shift imm1
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mov reg1,reg1, shift imm2
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to
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mov reg1,reg0, shift imm1+imm2
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}
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else if (taicpu(p).oper[2]^.shifterop^.shiftmode=taicpu(hp1).oper[2]^.shifterop^.shiftmode) or
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{ asr makes no use after a lsr, the asr can be foled into the lsr }
|
|
((taicpu(p).oper[2]^.shifterop^.shiftmode=SM_LSR) and (taicpu(hp1).oper[2]^.shifterop^.shiftmode=SM_ASR) ) then
|
|
begin
|
|
inc(taicpu(p).oper[2]^.shifterop^.shiftimm,taicpu(hp1).oper[2]^.shifterop^.shiftimm);
|
|
{ avoid overflows }
|
|
if taicpu(p).oper[2]^.shifterop^.shiftimm>31 then
|
|
case taicpu(p).oper[2]^.shifterop^.shiftmode of
|
|
SM_ROR:
|
|
taicpu(p).oper[2]^.shifterop^.shiftimm:=taicpu(p).oper[2]^.shifterop^.shiftimm and 31;
|
|
SM_ASR:
|
|
taicpu(p).oper[2]^.shifterop^.shiftimm:=31;
|
|
SM_LSR,
|
|
SM_LSL:
|
|
begin
|
|
hp1:=taicpu.op_reg_const(A_MOV,taicpu(p).oper[0]^.reg,0);
|
|
InsertLLItem(p.previous, p.next, hp1);
|
|
p.free;
|
|
p:=hp1;
|
|
end;
|
|
else
|
|
internalerror(2008072803);
|
|
end;
|
|
asml.insertbefore(tai_comment.Create(strpnew('Peephole ShiftShift2Shift 1 done')), p);
|
|
asml.remove(hp1);
|
|
hp1.free;
|
|
result := true;
|
|
end
|
|
{ fold
|
|
mov reg1,reg0, shift imm1
|
|
mov reg1,reg1, shift imm2
|
|
mov reg1,reg1, shift imm3 ...
|
|
}
|
|
else if getnextinstruction(hp1,hp2) and
|
|
MatchInstruction(hp2, A_MOV, [taicpu(p).condition], [PF_None]) and
|
|
(taicpu(hp2).ops=3) and
|
|
MatchOperand(taicpu(hp2).oper[0]^, taicpu(hp1).oper[0]^.reg) and
|
|
MatchOperand(taicpu(hp2).oper[1]^, taicpu(hp1).oper[0]^.reg) and
|
|
(taicpu(hp2).oper[2]^.typ = top_shifterop) and
|
|
(taicpu(hp2).oper[2]^.shifterop^.rs = NR_NO) then
|
|
begin
|
|
{ mov reg1,reg0, lsl imm1
|
|
mov reg1,reg1, lsr/asr imm2
|
|
mov reg1,reg1, lsl imm3 ...
|
|
|
|
if imm3<=imm1 and imm2>=imm3
|
|
to
|
|
mov reg1,reg0, lsl imm1
|
|
mov reg1,reg1, lsr/asr imm2-imm3
|
|
}
|
|
if (taicpu(p).oper[2]^.shifterop^.shiftmode=SM_LSL) and (taicpu(hp2).oper[2]^.shifterop^.shiftmode=SM_LSL) and
|
|
(taicpu(hp1).oper[2]^.shifterop^.shiftmode in [SM_ASR,SM_LSR]) and
|
|
(taicpu(hp2).oper[2]^.shifterop^.shiftimm<=taicpu(p).oper[2]^.shifterop^.shiftimm) and
|
|
(taicpu(hp1).oper[2]^.shifterop^.shiftimm>=taicpu(hp2).oper[2]^.shifterop^.shiftimm) then
|
|
begin
|
|
dec(taicpu(hp1).oper[2]^.shifterop^.shiftimm,taicpu(hp2).oper[2]^.shifterop^.shiftimm);
|
|
asml.insertbefore(tai_comment.Create(strpnew('Peephole ShiftShiftShift2ShiftShift 1 done')), p);
|
|
asml.remove(hp2);
|
|
hp2.free;
|
|
result := true;
|
|
if taicpu(hp1).oper[2]^.shifterop^.shiftimm=0 then
|
|
begin
|
|
asml.remove(hp1);
|
|
hp1.free;
|
|
end;
|
|
end
|
|
{ mov reg1,reg0, lsr/asr imm1
|
|
mov reg1,reg1, lsl imm2
|
|
mov reg1,reg1, lsr/asr imm3 ...
|
|
|
|
if imm3>=imm1 and imm2>=imm1
|
|
to
|
|
mov reg1,reg0, lsl imm2-imm1
|
|
mov reg1,reg1, lsr/asr imm3 ...
|
|
}
|
|
else if (taicpu(p).oper[2]^.shifterop^.shiftmode in [SM_ASR,SM_LSR]) and (taicpu(hp2).oper[2]^.shifterop^.shiftmode in [SM_ASR,SM_LSR]) and
|
|
(taicpu(hp1).oper[2]^.shifterop^.shiftmode=SM_LSL) and
|
|
(taicpu(hp2).oper[2]^.shifterop^.shiftimm>=taicpu(p).oper[2]^.shifterop^.shiftimm) and
|
|
(taicpu(hp1).oper[2]^.shifterop^.shiftimm>=taicpu(p).oper[2]^.shifterop^.shiftimm) then
|
|
begin
|
|
dec(taicpu(hp1).oper[2]^.shifterop^.shiftimm,taicpu(p).oper[2]^.shifterop^.shiftimm);
|
|
taicpu(hp1).oper[1]^.reg:=taicpu(p).oper[1]^.reg;
|
|
asml.insertbefore(tai_comment.Create(strpnew('Peephole ShiftShiftShift2ShiftShift 2 done')), p);
|
|
asml.remove(p);
|
|
p.free;
|
|
p:=hp2;
|
|
if taicpu(hp1).oper[2]^.shifterop^.shiftimm=0 then
|
|
begin
|
|
taicpu(hp2).oper[1]^.reg:=taicpu(hp1).oper[1]^.reg;
|
|
asml.remove(hp1);
|
|
hp1.free;
|
|
p:=hp2;
|
|
end;
|
|
result := true;
|
|
end;
|
|
end;
|
|
end;
|
|
{ Change the common
|
|
mov r0, r0, lsr #24
|
|
and r0, r0, #255
|
|
|
|
and remove the superfluous and
|
|
|
|
This could be extended to handle more cases.
|
|
}
|
|
if (taicpu(p).ops=3) and
|
|
(taicpu(p).oper[2]^.typ = top_shifterop) and
|
|
(taicpu(p).oper[2]^.shifterop^.rs = NR_NO) and
|
|
(taicpu(p).oper[2]^.shifterop^.shiftmode = SM_LSR) and
|
|
(taicpu(p).oper[2]^.shifterop^.shiftimm >= 24 ) and
|
|
getnextinstruction(p,hp1) and
|
|
MatchInstruction(hp1, A_AND, [taicpu(p).condition], [taicpu(p).oppostfix]) and
|
|
(taicpu(hp1).ops=3) and
|
|
MatchOperand(taicpu(p).oper[0]^, taicpu(hp1).oper[0]^) and
|
|
MatchOperand(taicpu(p).oper[0]^, taicpu(hp1).oper[1]^) and
|
|
(taicpu(hp1).oper[2]^.typ = top_const) and
|
|
{ Check if the AND actually would only mask out bits beeing already zero because of the shift
|
|
For LSR #25 and an AndConst of 255 that whould go like this:
|
|
255 and ((2 shl (32-25))-1)
|
|
which results in 127, which is one less a power-of-2, meaning all lower bits are set.
|
|
|
|
LSR #25 and AndConst of 254:
|
|
254 and ((2 shl (32-25))-1) = 126 -> lowest bit is clear, so we can't remove it.
|
|
}
|
|
ispowerof2((taicpu(hp1).oper[2]^.val and ((2 shl (32-taicpu(p).oper[2]^.shifterop^.shiftimm))-1))+1) then
|
|
begin
|
|
asml.insertbefore(tai_comment.Create(strpnew('Peephole LsrAnd2Lsr done')), hp1);
|
|
asml.remove(hp1);
|
|
hp1.free;
|
|
end;
|
|
|
|
{
|
|
optimize
|
|
mov rX, yyyy
|
|
....
|
|
}
|
|
if (taicpu(p).ops = 2) and
|
|
GetNextInstruction(p,hp1) and
|
|
(tai(hp1).typ = ait_instruction) then
|
|
begin
|
|
{
|
|
This changes the very common
|
|
mov r0, #0
|
|
str r0, [...]
|
|
mov r0, #0
|
|
str r0, [...]
|
|
|
|
and removes all superfluous mov instructions
|
|
}
|
|
if (taicpu(p).oper[1]^.typ = top_const) and
|
|
(taicpu(hp1).opcode=A_STR) then
|
|
while MatchInstruction(hp1, A_STR, [taicpu(p).condition], []) and
|
|
MatchOperand(taicpu(p).oper[0]^, taicpu(hp1).oper[0]^) and
|
|
GetNextInstruction(hp1, hp2) and
|
|
MatchInstruction(hp2, A_MOV, [taicpu(p).condition], [PF_None]) 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
|
|
{
|
|
This removes the first mov from
|
|
mov rX,...
|
|
mov rX,...
|
|
}
|
|
else if taicpu(hp1).opcode=A_MOV then
|
|
while MatchInstruction(hp1, A_MOV, [taicpu(p).condition], [taicpu(p).oppostfix]) and
|
|
(taicpu(hp1).ops = 2) and
|
|
MatchOperand(taicpu(p).oper[0]^, taicpu(hp1).oper[0]^) do
|
|
begin
|
|
asml.insertbefore(tai_comment.Create(strpnew('Peephole MovMov done')), p);
|
|
asml.remove(p);
|
|
p.free;
|
|
p:=hp1;
|
|
GetNextInstruction(hp1,hp1);
|
|
if not assigned(hp1) then
|
|
break;
|
|
end;
|
|
end;
|
|
{
|
|
change
|
|
mov r1, r0
|
|
add r1, r1, #1
|
|
to
|
|
add r1, r0, #1
|
|
|
|
Todo: Make it work for mov+cmp too
|
|
|
|
CAUTION! If this one is successful p might not be a mov instruction anymore!
|
|
}
|
|
if (taicpu(p).ops = 2) and
|
|
(taicpu(p).oper[1]^.typ = top_reg) and
|
|
(taicpu(p).oppostfix = PF_NONE) and
|
|
GetNextInstruction(p, hp1) and
|
|
(tai(hp1).typ = ait_instruction) and
|
|
(taicpu(hp1).opcode in [A_ADD, A_ADC, A_RSB, A_RSC, A_SUB, A_SBC,
|
|
A_AND, A_BIC, A_EOR, A_ORR, A_MOV, A_MVN]) and
|
|
{MOV and MVN might only have 2 ops}
|
|
(taicpu(hp1).ops = 3) and
|
|
(taicpu(hp1).condition in [C_NONE, taicpu(hp1).condition]) and
|
|
MatchOperand(taicpu(p).oper[0]^, taicpu(hp1).oper[0]^.reg) and
|
|
(taicpu(hp1).oper[1]^.typ = top_reg) and
|
|
(taicpu(hp1).oper[2]^.typ in [top_reg, top_const, top_shifterop]) then
|
|
begin
|
|
{ When we get here we still don't know if the registers match}
|
|
for I:=1 to 2 do
|
|
{
|
|
If the first loop was successful p will be replaced with hp1.
|
|
The checks will still be ok, because all required information
|
|
will also be in hp1 then.
|
|
}
|
|
if MatchOperand(taicpu(p).oper[0]^, taicpu(hp1).oper[I]^.reg) then
|
|
begin
|
|
asml.insertbefore(tai_comment.Create(strpnew('Peephole RedundantMovProcess done')), hp1);
|
|
taicpu(hp1).oper[I]^.reg := taicpu(p).oper[1]^.reg;
|
|
if p<>hp1 then
|
|
begin
|
|
asml.remove(p);
|
|
p.free;
|
|
p:=hp1;
|
|
end;
|
|
end;
|
|
end;
|
|
{ This folds shifterops into following instructions
|
|
mov r0, r1, lsl #8
|
|
add r2, r3, r0
|
|
|
|
to
|
|
|
|
add r2, r3, r1, lsl #8
|
|
CAUTION! If this one is successful p might not be a mov instruction anymore!
|
|
}
|
|
if (taicpu(p).opcode = A_MOV) and
|
|
(taicpu(p).ops = 3) and
|
|
(taicpu(p).oper[1]^.typ = top_reg) and
|
|
(taicpu(p).oper[2]^.typ = top_shifterop) and
|
|
(taicpu(p).oppostfix = PF_NONE) and
|
|
GetNextInstruction(p, hp1) and
|
|
(tai(hp1).typ = ait_instruction) and
|
|
(taicpu(hp1).ops >= 2) and {Currently we can't fold into another shifterop}
|
|
(taicpu(hp1).oper[taicpu(hp1).ops-1]^.typ = top_reg) and
|
|
(taicpu(hp1).oppostfix = PF_NONE) and
|
|
(taicpu(hp1).condition = taicpu(p).condition) and
|
|
(taicpu(hp1).opcode in [A_ADD, A_ADC, A_RSB, A_RSC, A_SUB, A_SBC,
|
|
A_AND, A_BIC, A_EOR, A_ORR, A_TEQ, A_TST,
|
|
A_CMP, A_CMN]) and
|
|
(
|
|
{Only ONE of the two src operands is allowed to match}
|
|
MatchOperand(taicpu(p).oper[0]^, taicpu(hp1).oper[taicpu(hp1).ops-2]^) xor
|
|
MatchOperand(taicpu(p).oper[0]^, taicpu(hp1).oper[taicpu(hp1).ops-1]^)
|
|
) then
|
|
begin
|
|
CopyUsedRegs(TmpUsedRegs);
|
|
UpdateUsedRegs(TmpUsedRegs, tai(p.next));
|
|
if taicpu(hp1).opcode in [A_TST, A_TEQ, A_CMN] then
|
|
I2:=0
|
|
else
|
|
I2:=1;
|
|
if not(RegUsedAfterInstruction(taicpu(p).oper[0]^.reg,hp1,TmpUsedRegs)) then
|
|
for I:=I2 to taicpu(hp1).ops-1 do
|
|
if MatchOperand(taicpu(p).oper[0]^, taicpu(hp1).oper[I]^.reg) then
|
|
begin
|
|
{ If the parameter matched on the second op from the RIGHT
|
|
we have to switch the parameters, this will not happen for CMP
|
|
were we're only evaluating the most right parameter
|
|
}
|
|
if I <> taicpu(hp1).ops-1 then
|
|
begin
|
|
{The SUB operators need to be changed when we swap parameters}
|
|
case taicpu(hp1).opcode of
|
|
A_SUB: tempop:=A_RSB;
|
|
A_SBC: tempop:=A_RSC;
|
|
A_RSB: tempop:=A_SUB;
|
|
A_RSC: tempop:=A_SBC;
|
|
else tempop:=taicpu(hp1).opcode;
|
|
end;
|
|
if taicpu(hp1).ops = 3 then
|
|
hp2:=taicpu.op_reg_reg_reg_shifterop(tempop,
|
|
taicpu(hp1).oper[0]^.reg, taicpu(hp1).oper[2]^.reg,
|
|
taicpu(p).oper[1]^.reg, taicpu(p).oper[2]^.shifterop^)
|
|
else
|
|
hp2:=taicpu.op_reg_reg_shifterop(tempop,
|
|
taicpu(hp1).oper[0]^.reg, taicpu(p).oper[1]^.reg,
|
|
taicpu(p).oper[2]^.shifterop^);
|
|
end
|
|
else
|
|
if taicpu(hp1).ops = 3 then
|
|
hp2:=taicpu.op_reg_reg_reg_shifterop(taicpu(hp1).opcode,
|
|
taicpu(hp1).oper[0]^.reg, taicpu(hp1).oper[1]^.reg,
|
|
taicpu(p).oper[1]^.reg, taicpu(p).oper[2]^.shifterop^)
|
|
else
|
|
hp2:=taicpu.op_reg_reg_shifterop(taicpu(hp1).opcode,
|
|
taicpu(hp1).oper[0]^.reg, taicpu(p).oper[1]^.reg,
|
|
taicpu(p).oper[2]^.shifterop^);
|
|
asml.insertbefore(hp2, p);
|
|
asml.remove(p);
|
|
asml.remove(hp1);
|
|
p.free;
|
|
hp1.free;
|
|
p:=hp2;
|
|
GetNextInstruction(p,hp1);
|
|
asml.insertbefore(tai_comment.Create(strpnew('Peephole FoldShiftProcess done')), p);
|
|
break;
|
|
end;
|
|
ReleaseUsedRegs(TmpUsedRegs);
|
|
end;
|
|
|
|
{
|
|
Often we see shifts and then a superfluous mov to another register
|
|
In the future this might be handled in RedundantMovProcess when it uses RegisterTracking
|
|
}
|
|
if (taicpu(p).opcode = A_MOV) and
|
|
GetNextInstruction(p, hp1) then
|
|
RemoveSuperfluousMove(p, hp1, 'MovMov2Mov');
|
|
end;
|
|
A_ADD,
|
|
A_ADC,
|
|
A_RSB,
|
|
A_RSC,
|
|
A_SUB,
|
|
A_SBC,
|
|
A_AND,
|
|
A_BIC,
|
|
A_EOR,
|
|
A_ORR,
|
|
A_MLA,
|
|
A_MUL:
|
|
begin
|
|
{
|
|
change
|
|
and reg2,reg1,const1
|
|
and reg2,reg2,const2
|
|
to
|
|
and reg2,reg1,(const1 and const2)
|
|
}
|
|
if (taicpu(p).opcode = A_AND) and
|
|
(taicpu(p).oper[1]^.typ = top_reg) and
|
|
(taicpu(p).oper[2]^.typ = top_const) and
|
|
GetNextInstruction(p, hp1) and
|
|
MatchInstruction(hp1, A_AND, [taicpu(p).condition], [PF_None]) and
|
|
MatchOperand(taicpu(hp1).oper[0]^, taicpu(p).oper[0]^.reg) and
|
|
MatchOperand(taicpu(hp1).oper[1]^, taicpu(p).oper[0]^.reg) and
|
|
(taicpu(hp1).oper[2]^.typ = top_const) then
|
|
begin
|
|
asml.insertbefore(tai_comment.Create(strpnew('Peephole AndAnd2And done')), p);
|
|
taicpu(p).loadConst(2,taicpu(p).oper[2]^.val and taicpu(hp1).oper[2]^.val);
|
|
taicpu(p).oppostfix:=taicpu(hp1).oppostfix;
|
|
asml.remove(hp1);
|
|
hp1.free;
|
|
end;
|
|
{
|
|
change
|
|
add reg1, ...
|
|
mov reg2, reg1
|
|
to
|
|
add reg2, ...
|
|
}
|
|
if GetNextInstruction(p, hp1) then
|
|
RemoveSuperfluousMove(p, hp1, 'DataMov2Data');
|
|
end;
|
|
A_CMP:
|
|
begin
|
|
{
|
|
change
|
|
cmp reg,const1
|
|
moveq reg,const1
|
|
movne reg,const2
|
|
to
|
|
cmp reg,const1
|
|
movne reg,const2
|
|
}
|
|
if (taicpu(p).oper[1]^.typ = top_const) and
|
|
GetNextInstruction(p, hp1) and
|
|
MatchInstruction(hp1, A_MOV, [C_EQ, C_NE], [PF_NONE]) and
|
|
(taicpu(hp1).oper[1]^.typ = top_const) and
|
|
GetNextInstruction(hp1, hp2) and
|
|
MatchInstruction(hp2, A_MOV, [C_EQ, C_NE], [PF_NONE]) and
|
|
(taicpu(hp1).oper[1]^.typ = top_const) then
|
|
begin
|
|
RemoveRedundantMove(p, hp1, asml);
|
|
RemoveRedundantMove(p, hp2, asml);
|
|
end;
|
|
end;
|
|
end;
|
|
end;
|
|
end;
|
|
end;
|
|
|
|
|
|
{ instructions modifying the CPSR can be only the last instruction }
|
|
function MustBeLast(p : tai) : boolean;
|
|
begin
|
|
Result:=(p.typ=ait_instruction) and
|
|
((taicpu(p).opcode in [A_BL,A_BLX,A_CMP,A_CMN,A_SWI,A_TEQ,A_TST,A_CMF,A_CMFE {,A_MSR}]) or
|
|
((taicpu(p).ops>=1) and (taicpu(p).oper[0]^.typ=top_reg) and (taicpu(p).oper[0]^.reg=NR_PC)) or
|
|
(taicpu(p).oppostfix=PF_S));
|
|
end;
|
|
|
|
|
|
procedure TCpuAsmOptimizer.PeepHoleOptPass2;
|
|
var
|
|
p,hp1,hp2: tai;
|
|
l : longint;
|
|
condition : tasmcond;
|
|
hp3: tai;
|
|
WasLast: boolean;
|
|
{ UsedRegs, TmpUsedRegs: TRegSet; }
|
|
|
|
begin
|
|
p := BlockStart;
|
|
{ UsedRegs := []; }
|
|
while (p <> BlockEnd) Do
|
|
begin
|
|
{ UpdateUsedRegs(UsedRegs, tai(p.next)); }
|
|
case p.Typ Of
|
|
Ait_Instruction:
|
|
begin
|
|
case taicpu(p).opcode Of
|
|
A_B:
|
|
if taicpu(p).condition<>C_None then
|
|
begin
|
|
{ check for
|
|
Bxx xxx
|
|
<several instructions>
|
|
xxx:
|
|
}
|
|
l:=0;
|
|
WasLast:=False;
|
|
GetNextInstruction(p, hp1);
|
|
while assigned(hp1) and
|
|
(l<=4) and
|
|
CanBeCond(hp1) and
|
|
{ stop on labels }
|
|
not(hp1.typ=ait_label) do
|
|
begin
|
|
inc(l);
|
|
if MustBeLast(hp1) then
|
|
begin
|
|
WasLast:=True;
|
|
GetNextInstruction(hp1,hp1);
|
|
break;
|
|
end
|
|
else
|
|
GetNextInstruction(hp1,hp1);
|
|
end;
|
|
if assigned(hp1) then
|
|
begin
|
|
if FindLabel(tasmlabel(taicpu(p).oper[0]^.ref^.symbol),hp1) then
|
|
begin
|
|
if (l<=4) and (l>0) then
|
|
begin
|
|
condition:=inverse_cond(taicpu(p).condition);
|
|
hp2:=p;
|
|
GetNextInstruction(p,hp1);
|
|
p:=hp1;
|
|
repeat
|
|
if hp1.typ=ait_instruction then
|
|
taicpu(hp1).condition:=condition;
|
|
if MustBeLast(hp1) then
|
|
begin
|
|
GetNextInstruction(hp1,hp1);
|
|
break;
|
|
end
|
|
else
|
|
GetNextInstruction(hp1,hp1);
|
|
until not(assigned(hp1)) or
|
|
not(CanBeCond(hp1)) or
|
|
(hp1.typ=ait_label);
|
|
{ wait with removing else GetNextInstruction could
|
|
ignore the label if it was the only usage in the
|
|
jump moved away }
|
|
tasmlabel(taicpu(hp2).oper[0]^.ref^.symbol).decrefs;
|
|
asml.remove(hp2);
|
|
hp2.free;
|
|
continue;
|
|
end;
|
|
end
|
|
else
|
|
{ do not perform further optimizations if there is inctructon
|
|
in block #1 which can not be optimized.
|
|
}
|
|
if not WasLast then
|
|
begin
|
|
{ check further for
|
|
Bcc xxx
|
|
<several instructions 1>
|
|
B yyy
|
|
xxx:
|
|
<several instructions 2>
|
|
yyy:
|
|
}
|
|
{ hp2 points to jmp yyy }
|
|
hp2:=hp1;
|
|
{ skip hp1 to xxx }
|
|
GetNextInstruction(hp1, hp1);
|
|
if assigned(hp2) and
|
|
assigned(hp1) and
|
|
(l<=3) and
|
|
(hp2.typ=ait_instruction) and
|
|
(taicpu(hp2).is_jmp) and
|
|
(taicpu(hp2).condition=C_None) and
|
|
{ real label and jump, no further references to the
|
|
label are allowed }
|
|
(tasmlabel(taicpu(p).oper[0]^.ref^.symbol).getrefs=2) and
|
|
FindLabel(tasmlabel(taicpu(p).oper[0]^.ref^.symbol),hp1) then
|
|
begin
|
|
l:=0;
|
|
{ skip hp1 to <several moves 2> }
|
|
GetNextInstruction(hp1, hp1);
|
|
while assigned(hp1) and
|
|
CanBeCond(hp1) do
|
|
begin
|
|
inc(l);
|
|
GetNextInstruction(hp1, hp1);
|
|
end;
|
|
{ hp1 points to yyy: }
|
|
if assigned(hp1) and
|
|
FindLabel(tasmlabel(taicpu(hp2).oper[0]^.ref^.symbol),hp1) then
|
|
begin
|
|
condition:=inverse_cond(taicpu(p).condition);
|
|
GetNextInstruction(p,hp1);
|
|
hp3:=p;
|
|
p:=hp1;
|
|
repeat
|
|
if hp1.typ=ait_instruction then
|
|
taicpu(hp1).condition:=condition;
|
|
GetNextInstruction(hp1,hp1);
|
|
until not(assigned(hp1)) or
|
|
not(CanBeCond(hp1));
|
|
{ hp2 is still at jmp yyy }
|
|
GetNextInstruction(hp2,hp1);
|
|
{ hp2 is now at xxx: }
|
|
condition:=inverse_cond(condition);
|
|
GetNextInstruction(hp1,hp1);
|
|
{ hp1 is now at <several movs 2> }
|
|
repeat
|
|
taicpu(hp1).condition:=condition;
|
|
GetNextInstruction(hp1,hp1);
|
|
until not(assigned(hp1)) or
|
|
not(CanBeCond(hp1)) or
|
|
(hp1.typ=ait_label);
|
|
{
|
|
asml.remove(hp1.next)
|
|
hp1.next.free;
|
|
asml.remove(hp1);
|
|
hp1.free;
|
|
}
|
|
{ remove Bcc }
|
|
tasmlabel(taicpu(hp3).oper[0]^.ref^.symbol).decrefs;
|
|
asml.remove(hp3);
|
|
hp3.free;
|
|
{ remove jmp }
|
|
tasmlabel(taicpu(hp2).oper[0]^.ref^.symbol).decrefs;
|
|
asml.remove(hp2);
|
|
hp2.free;
|
|
continue;
|
|
end;
|
|
end;
|
|
end;
|
|
end;
|
|
end;
|
|
end;
|
|
end;
|
|
end;
|
|
p := tai(p.next)
|
|
end;
|
|
end;
|
|
|
|
function TCpuAsmOptimizer.RegInInstruction(Reg: TRegister; p1: tai): Boolean;
|
|
begin
|
|
If (p1.typ = ait_instruction) and (taicpu(p1).opcode=A_BL) then
|
|
Result:=true
|
|
else
|
|
Result:=inherited RegInInstruction(Reg, p1);
|
|
end;
|
|
|
|
const
|
|
{ set of opcode which might or do write to memory }
|
|
{ TODO : extend armins.dat to contain r/w info }
|
|
opcode_could_mem_write = [A_B,A_BL,A_BLX,A_BKPT,A_BX,A_STR,A_STRB,A_STRBT,
|
|
A_STRH,A_STRT,A_STF,A_SFM,A_STM,A_FSTS,A_FSTD];
|
|
|
|
function TCpuPreRegallocScheduler.PeepHoleOptPass1Cpu(var p: tai): boolean;
|
|
{ TODO : schedule also forward }
|
|
{ TODO : schedule distance > 1 }
|
|
var
|
|
hp1,hp2,hp3,hp4,hp5 : tai;
|
|
list : TAsmList;
|
|
begin
|
|
result:=true;
|
|
list:=TAsmList.Create;
|
|
p := BlockStart;
|
|
{ UsedRegs := []; }
|
|
while (p <> BlockEnd) Do
|
|
begin
|
|
if (p.typ=ait_instruction) and
|
|
GetNextInstruction(p,hp1) and
|
|
(hp1.typ=ait_instruction) and
|
|
{ for now we don't reschedule if the previous instruction changes potentially a memory location }
|
|
( (not(taicpu(p).opcode in opcode_could_mem_write) and
|
|
not(RegModifiedByInstruction(NR_PC,p)) and
|
|
(taicpu(hp1).opcode in [A_LDR,A_LDRB,A_LDRH,A_LDRSB,A_LDRSH])
|
|
) or
|
|
((taicpu(p).opcode in [A_STM,A_STRB,A_STRH,A_STR]) and
|
|
(taicpu(hp1).opcode in [A_LDR,A_LDRB,A_LDRH,A_LDRSB,A_LDRSH]) and
|
|
((taicpu(hp1).oper[1]^.ref^.base=NR_PC) or
|
|
(assigned(taicpu(hp1).oper[1]^.ref^.symboldata) and
|
|
(taicpu(hp1).oper[1]^.ref^.offset=0)
|
|
)
|
|
) or
|
|
{ try to prove that the memory accesses don't overlapp }
|
|
((taicpu(p).opcode in [A_STRB,A_STRH,A_STR]) and
|
|
(taicpu(hp1).opcode in [A_LDR,A_LDRB,A_LDRH,A_LDRSB,A_LDRSH]) and
|
|
(taicpu(p).oper[1]^.ref^.base=taicpu(hp1).oper[1]^.ref^.base) and
|
|
(taicpu(p).oppostfix=PF_None) and
|
|
(taicpu(hp1).oppostfix=PF_None) and
|
|
(taicpu(p).oper[1]^.ref^.index=NR_NO) and
|
|
(taicpu(hp1).oper[1]^.ref^.index=NR_NO) and
|
|
{ get operand sizes and check if the offset distance is large enough to ensure no overlapp }
|
|
(abs(taicpu(p).oper[1]^.ref^.offset-taicpu(hp1).oper[1]^.ref^.offset)>=max(tcgsize2size[reg_cgsize(taicpu(p).oper[0]^.reg)],tcgsize2size[reg_cgsize(taicpu(hp1).oper[0]^.reg)]))
|
|
)
|
|
)
|
|
) and
|
|
GetNextInstruction(hp1,hp2) and
|
|
(hp2.typ=ait_instruction) and
|
|
{ loaded register used by next instruction? }
|
|
(RegInInstruction(taicpu(hp1).oper[0]^.reg,hp2)) and
|
|
{ loaded register not used by previous instruction? }
|
|
not(RegInInstruction(taicpu(hp1).oper[0]^.reg,p)) and
|
|
{ same condition? }
|
|
(taicpu(p).condition=taicpu(hp1).condition) and
|
|
{ first instruction might not change the register used as base }
|
|
((taicpu(hp1).oper[1]^.ref^.base=NR_NO) or
|
|
not(RegModifiedByInstruction(taicpu(hp1).oper[1]^.ref^.base,p))
|
|
) and
|
|
{ first instruction might not change the register used as index }
|
|
((taicpu(hp1).oper[1]^.ref^.index=NR_NO) or
|
|
not(RegModifiedByInstruction(taicpu(hp1).oper[1]^.ref^.index,p))
|
|
) then
|
|
begin
|
|
hp3:=tai(p.Previous);
|
|
hp5:=tai(p.next);
|
|
asml.Remove(p);
|
|
{ if there is a reg. dealloc instruction associated with p, move it together with p }
|
|
|
|
{ before the instruction? }
|
|
while assigned(hp3) and (hp3.typ<>ait_instruction) do
|
|
begin
|
|
if (hp3.typ=ait_regalloc) and (tai_regalloc(hp3).ratype in [ra_dealloc]) and
|
|
RegInInstruction(tai_regalloc(hp3).reg,p) then
|
|
begin
|
|
hp4:=hp3;
|
|
hp3:=tai(hp3.Previous);
|
|
asml.Remove(hp4);
|
|
list.Concat(hp4);
|
|
end
|
|
else
|
|
hp3:=tai(hp3.Previous);
|
|
end;
|
|
list.Concat(p);
|
|
{ after the instruction? }
|
|
while assigned(hp5) and (hp5.typ<>ait_instruction) do
|
|
begin
|
|
if (hp5.typ=ait_regalloc) and (tai_regalloc(hp5).ratype in [ra_dealloc]) and
|
|
RegInInstruction(tai_regalloc(hp5).reg,p) then
|
|
begin
|
|
hp4:=hp5;
|
|
hp5:=tai(hp5.next);
|
|
asml.Remove(hp4);
|
|
list.Concat(hp4);
|
|
end
|
|
else
|
|
hp5:=tai(hp5.Next);
|
|
end;
|
|
|
|
asml.Remove(hp1);
|
|
{$ifdef DEBUG_PREREGSCHEDULER}
|
|
asml.InsertBefore(tai_comment.Create(strpnew('Rescheduled')),hp2);
|
|
{$endif DEBUG_PREREGSCHEDULER}
|
|
asml.InsertBefore(hp1,hp2);
|
|
asml.InsertListBefore(hp2,list);
|
|
end;
|
|
p := tai(p.next)
|
|
end;
|
|
list.Free;
|
|
end;
|
|
|
|
|
|
procedure TCpuThumb2AsmOptimizer.PeepHoleOptPass2;
|
|
begin
|
|
{ TODO: Add optimizer code }
|
|
end;
|
|
|
|
begin
|
|
casmoptimizer:=TCpuAsmOptimizer;
|
|
cpreregallocscheduler:=TCpuPreRegallocScheduler;
|
|
End.
|