fpc/compiler/z80/aoptcpub.pas
2020-10-13 19:59:01 +00:00

320 lines
13 KiB
ObjectPascal

{
Copyright (c) 1998-2002 by Jonas Maebe, member of the Free Pascal
Development Team
This unit contains several types and constants necessary for the
optimizer to work on the Z80 architecture
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
****************************************************************************
}
Unit aoptcpub; { Assembler OPTimizer CPU specific Base }
{$i fpcdefs.inc}
{ enable the following define if memory references can have a scaled index }
{ define RefsHaveScale}
{ enable the following define if memory references can have a segment }
{ override }
{ define RefsHaveSegment}
Interface
Uses
cpubase,
cgbase,
aasmcpu,aasmtai,
AOptBase;
Type
{ type of a normal instruction }
TInstr = Taicpu;
PInstr = ^TInstr;
{ ************************************************************************* }
{ **************************** TCondRegs ********************************** }
{ ************************************************************************* }
{ Info about the conditional registers }
TCondRegs = Object
Constructor Init;
Destructor Done;
End;
{ ************************************************************************* }
{ **************************** TAoptBaseCpu ******************************* }
{ ************************************************************************* }
TAoptBaseCpu = class(TAoptBase)
{ checks whether reading the value in reg1 depends on the value of reg2. This
is very similar to SuperRegisterEquals, except it takes into account that
R_SUBH and R_SUBL are independendent (e.g. reading from AL does not
depend on the value in AH). }
function Reg1ReadDependsOnReg2(reg1, reg2: tregister): boolean;
function RegModifiedByInstruction(Reg: TRegister; p1: tai): boolean; override;
End;
{ ************************************************************************* }
{ ******************************* Constants ******************************* }
{ ************************************************************************* }
Const
{ the maximum number of things (registers, memory, ...) a single instruction }
{ changes }
MaxCh = 2;
{ the maximum number of operands an instruction has }
MaxOps = 2;
{Oper index of operand that contains the source (reference) with a load }
{instruction }
LoadSrc = 1;
{Oper index of operand that contains the destination (register) with a load }
{instruction }
LoadDst = 0;
{Oper index of operand that contains the source (register) with a store }
{instruction }
StoreSrc = 1;
{Oper index of operand that contains the destination (reference) with a load }
{instruction }
StoreDst = 0;
aopt_uncondjmp = [A_JP,A_JR,A_JRJP];
aopt_condjmp = [A_JP,A_JR,A_JRJP];
Implementation
Uses
verbose;
{ ************************************************************************* }
{ **************************** TCondRegs ********************************** }
{ ************************************************************************* }
Constructor TCondRegs.init;
Begin
End;
Destructor TCondRegs.Done; {$ifdef inl} inline; {$endif inl}
Begin
End;
function TAoptBaseCpu.Reg1ReadDependsOnReg2(reg1, reg2: tregister): boolean;
begin
case reg1 of
NR_AF:
result:=(reg2=NR_A) or (reg2=NR_AF) or SuperRegistersEqual(reg2,NR_DEFAULTFLAGS);
NR_A:
result:=(reg2=NR_A) or (reg2=NR_AF);
NR_F:
result:=SuperRegistersEqual(reg2,NR_DEFAULTFLAGS);
NR_BC:
result:=(reg2=NR_B) or (reg2=NR_C) or (reg2=NR_BC);
NR_B:
result:=(reg2=NR_B) or (reg2=NR_BC);
NR_C:
result:=(reg2=NR_C) or (reg2=NR_BC);
NR_DE:
result:=(reg2=NR_D) or (reg2=NR_E) or (reg2=NR_DE);
NR_D:
result:=(reg2=NR_D) or (reg2=NR_DE);
NR_E:
result:=(reg2=NR_E) or (reg2=NR_DE);
NR_HL:
result:=(reg2=NR_H) or (reg2=NR_L) or (reg2=NR_HL);
NR_H:
result:=(reg2=NR_H) or (reg2=NR_HL);
NR_L:
result:=(reg2=NR_L) or (reg2=NR_HL);
NR_AF_:
result:=(reg2=NR_A_) or (reg2=NR_AF_) or SuperRegistersEqual(reg2,NR_F_);
NR_A_:
result:=(reg2=NR_A_) or (reg2=NR_AF_);
NR_F_:
result:=SuperRegistersEqual(reg2,NR_F_);
NR_BC_:
result:=(reg2=NR_B_) or (reg2=NR_C_) or (reg2=NR_BC_);
NR_B_:
result:=(reg2=NR_B_) or (reg2=NR_BC_);
NR_C_:
result:=(reg2=NR_C_) or (reg2=NR_BC_);
NR_DE_:
result:=(reg2=NR_D_) or (reg2=NR_E_) or (reg2=NR_DE_);
NR_D_:
result:=(reg2=NR_D_) or (reg2=NR_DE_);
NR_E_:
result:=(reg2=NR_E_) or (reg2=NR_DE_);
NR_HL_:
result:=(reg2=NR_H_) or (reg2=NR_L_) or (reg2=NR_HL_);
NR_H_:
result:=(reg2=NR_H_) or (reg2=NR_HL_);
NR_L_:
result:=(reg2=NR_L_) or (reg2=NR_HL_);
else
result:=reg1=reg2;
end;
end;
function TAoptBaseCpu.RegModifiedByInstruction(Reg: TRegister; p1: tai): boolean;
var
i : Longint;
p: taicpu;
begin
p:=taicpu(p1);
result:=false;
for i:=0 to p.ops-1 do
if (p.oper[i]^.typ=top_reg) and Reg1ReadDependsOnReg2(Reg,p.oper[i]^.reg) and (p.spilling_get_operation_type(i) in [operand_write,operand_readwrite]) then
begin
result:=true;
exit;
end;
case p.opcode of
A_LD,A_EX,A_ADD,A_ADC,A_SUB,A_SBC,A_AND,A_OR,A_XOR,A_CP,A_INC,A_DEC,
A_CCF,A_SCF,A_NOP,A_HALT,A_DI,A_EI,A_IM,A_RLC,A_RL,A_RRC,A_RR,A_SLA,
A_SRA,A_SRL,A_BIT,A_SET,A_RES,A_JP,A_JR,A_JRJP,A_CALL,A_RET,A_RETI,A_RETN,
A_RST,A_IN,A_OUT:
;
A_PUSH,A_POP:
result:=Reg1ReadDependsOnReg2(Reg,NR_SP);
A_EXX:
result:=Reg1ReadDependsOnReg2(Reg,NR_BC) or Reg1ReadDependsOnReg2(Reg,NR_BC_) or
Reg1ReadDependsOnReg2(Reg,NR_DE) or Reg1ReadDependsOnReg2(Reg,NR_DE_) or
Reg1ReadDependsOnReg2(Reg,NR_HL) or Reg1ReadDependsOnReg2(Reg,NR_HL_);
A_LDI,A_LDIR,A_LDD,A_LDDR:
result:=Reg1ReadDependsOnReg2(Reg,NR_BC) or
Reg1ReadDependsOnReg2(Reg,NR_DE) or
Reg1ReadDependsOnReg2(Reg,NR_HL);
A_CPI,A_CPIR,A_CPD,A_CPDR:
result:=Reg1ReadDependsOnReg2(Reg,NR_BC) or
Reg1ReadDependsOnReg2(Reg,NR_HL);
A_DAA,A_CPL,A_NEG,A_RLCA,A_RLA,A_RRCA,A_RRA,A_RLD,A_RRD:
result:=Reg1ReadDependsOnReg2(Reg,NR_A);
A_DJNZ:
result:=Reg1ReadDependsOnReg2(Reg,NR_B);
A_INI,A_INIR,A_IND,A_INDR,A_OUTI,A_OTIR,A_OUTD,A_OTDR:
result:=Reg1ReadDependsOnReg2(Reg,NR_B) or
Reg1ReadDependsOnReg2(Reg,NR_HL);
else
internalerror(2020052001);
end;
if not result and SuperRegistersEqual(reg,NR_DEFAULTFLAGS) then
begin
case p.opcode of
A_PUSH,A_POP,A_EX,A_EXX,A_NOP,A_HALT,A_DI,A_EI,A_IM,A_SET,A_RES,A_JP,A_JR,A_JRJP,A_DJNZ,A_CALL,A_RET,A_RETI,A_RETN,A_RST,A_OUT:
result:=false;
A_LD:
begin
if p.ops<>2 then
internalerror(2020051115);
{ LD A,I or LD A,R ? }
if (p.oper[0]^.typ=top_reg) and (p.oper[0]^.reg=NR_A) and
(p.oper[1]^.typ=top_reg) and ((p.oper[1]^.reg=NR_I) or (p.oper[1]^.reg=NR_R)) then
result:=Reg1ReadDependsOnReg2(Reg,NR_ADDSUBTRACTFLAG) or
Reg1ReadDependsOnReg2(Reg,NR_PARITYOVERFLOWFLAG) or
Reg1ReadDependsOnReg2(Reg,NR_HALFCARRYFLAG) or
Reg1ReadDependsOnReg2(Reg,NR_ZEROFLAG) or
Reg1ReadDependsOnReg2(Reg,NR_SIGNFLAG)
else
result:=false;
end;
A_LDI,A_LDIR,A_LDD,A_LDDR:
result:=Reg1ReadDependsOnReg2(Reg,NR_ADDSUBTRACTFLAG) or
Reg1ReadDependsOnReg2(Reg,NR_PARITYOVERFLOWFLAG) or
Reg1ReadDependsOnReg2(Reg,NR_HALFCARRYFLAG);
A_INC,A_DEC:
begin
if p.ops<>1 then
internalerror(2020051613);
if (p.oper[0]^.typ=top_reg) and ((p.oper[0]^.reg=NR_BC) or
(p.oper[0]^.reg=NR_DE) or
(p.oper[0]^.reg=NR_HL) or
(p.oper[0]^.reg=NR_SP) or
(p.oper[0]^.reg=NR_IX) or
(p.oper[0]^.reg=NR_IY)) then
result:=false
else
result:=Reg1ReadDependsOnReg2(Reg,NR_ADDSUBTRACTFLAG) or
Reg1ReadDependsOnReg2(Reg,NR_PARITYOVERFLOWFLAG) or
Reg1ReadDependsOnReg2(Reg,NR_HALFCARRYFLAG) or
Reg1ReadDependsOnReg2(Reg,NR_ZEROFLAG) or
Reg1ReadDependsOnReg2(Reg,NR_SIGNFLAG);
end;
A_CPI,A_CPIR,A_CPD,A_CPDR,A_RLD,A_RRD,A_BIT,A_INI,A_INIR,A_IND,A_INDR,A_OUTI,A_OTIR,A_OUTD,A_OTDR:
result:=Reg1ReadDependsOnReg2(Reg,NR_ADDSUBTRACTFLAG) or
Reg1ReadDependsOnReg2(Reg,NR_PARITYOVERFLOWFLAG) or
Reg1ReadDependsOnReg2(Reg,NR_HALFCARRYFLAG) or
Reg1ReadDependsOnReg2(Reg,NR_ZEROFLAG) or
Reg1ReadDependsOnReg2(Reg,NR_SIGNFLAG);
A_ADD:
begin
if p.ops<>2 then
internalerror(2020051611);
if (p.oper[0]^.typ=top_reg) and ((p.oper[0]^.reg=NR_HL) or (p.oper[0]^.reg=NR_IX) or (p.oper[0]^.reg=NR_IY)) then
result:=Reg1ReadDependsOnReg2(Reg,NR_HALFCARRYFLAG) or
Reg1ReadDependsOnReg2(Reg,NR_ADDSUBTRACTFLAG) or
Reg1ReadDependsOnReg2(Reg,NR_CARRYFLAG)
else
result:=true;
end;
A_ADC,A_SUB,A_SBC,A_AND,A_OR,A_XOR,A_CP,A_NEG,A_RLC,A_RL,A_RRC,A_RR,A_SLA,A_SRA,A_SRL:
result:=true;
A_DAA:
result:=Reg1ReadDependsOnReg2(Reg,NR_PARITYOVERFLOWFLAG) or
Reg1ReadDependsOnReg2(Reg,NR_HALFCARRYFLAG) or
Reg1ReadDependsOnReg2(Reg,NR_ZEROFLAG) or
Reg1ReadDependsOnReg2(Reg,NR_SIGNFLAG) or
Reg1ReadDependsOnReg2(Reg,NR_CARRYFLAG);
A_CPL:
result:=Reg1ReadDependsOnReg2(Reg,NR_HALFCARRYFLAG) or
Reg1ReadDependsOnReg2(Reg,NR_ADDSUBTRACTFLAG);
A_CCF,A_SCF,A_RLCA,A_RLA,A_RRCA,A_RRA:
result:=Reg1ReadDependsOnReg2(Reg,NR_HALFCARRYFLAG) or
Reg1ReadDependsOnReg2(Reg,NR_ADDSUBTRACTFLAG) or
Reg1ReadDependsOnReg2(Reg,NR_CARRYFLAG);
A_IN:
begin
if p.ops<>2 then
internalerror(2020051614);
if (p.oper[1]^.typ=top_ref) and ((p.oper[1]^.ref^.base=NR_C) or (p.oper[1]^.ref^.index=NR_C)) then
result:=Reg1ReadDependsOnReg2(Reg,NR_ADDSUBTRACTFLAG) or
Reg1ReadDependsOnReg2(Reg,NR_PARITYOVERFLOWFLAG) or
Reg1ReadDependsOnReg2(Reg,NR_HALFCARRYFLAG) or
Reg1ReadDependsOnReg2(Reg,NR_ZEROFLAG) or
Reg1ReadDependsOnReg2(Reg,NR_SIGNFLAG)
else
result:=false;
end;
else
internalerror(2020051113);
end;
end;
end;
End.