fpc/compiler/csopt386.pas
2000-02-24 18:41:38 +00:00

1372 lines
54 KiB
ObjectPascal

{
$Id$
Copyright (c) 1998-2000 by Jonas Maebe
This unit contains the common subexpression elimination procedure.
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 CSOpt386;
{$ifdef newOptimizations}
{$define foropt}
{$define replacereg}
{$define arithopt}
{$define foldarithops}
{$endif newOptimizations}
Interface
Uses aasm;
{Procedure CSOpt386(First, Last: Pai);}
Procedure CSE(AsmL: PAasmOutput; First, Last: Pai);
Implementation
Uses
CObjects, verbose, hcodegen, globals,cpubase,cpuasm,DAOpt386, tgeni386;
{
Function PaiInSequence(P: Pai; Const Seq: TContent): Boolean;
Var P1: Pai;
Counter: Byte;
TmpResult: Boolean;
Begin
TmpResult := False;
P1 := Seq.StartMod;
Counter := 1;
While Not(TmpResult) And
(Counter <= Seq.NrOfMods) Do
Begin
If (P = P1) Then TmpResult := True;
Inc(Counter);
p1 := Pai(p1^.Next);
End;
PaiInSequence := TmpResult;
End;
}
Function CheckSequence(p: Pai; Reg: TRegister; Var Found: Longint; Var RegInfo: TRegInfo): Boolean;
{checks whether the current instruction sequence (starting with p) and the
one between StartMod and EndMod of Reg are the same. If so, the number of
instructions that match is stored in Found and true is returned, otherwise
Found holds the number of instructions between StartMod and EndMod and false
is returned}
Var hp2, hp3{, EndMod}: Pai;
PrevNonRemovablePai: Pai;
Cnt, OldNrOfMods: Longint;
OrgRegInfo, HighRegInfo: TRegInfo;
HighFound, OrgRegFound: Byte;
RegCounter: TRegister;
OrgRegResult: Boolean;
TmpResult: Boolean;
TmpState: Byte;
Begin {CheckSequence}
Reg := Reg32(Reg);
TmpResult := False;
FillChar(OrgRegInfo, SizeOf(OrgRegInfo), 0);
OrgRegFound := 0;
HighFound := 0;
OrgRegResult := False;
RegCounter := R_EAX;
GetLastInstruction(p, PrevNonRemovablePai);
While (RegCounter <= R_EDI) And
(PPaiProp(PrevNonRemovablePai^.OptInfo)^.Regs[RegCounter].Typ <> Con_Ref) Do
Inc(RegCounter);
While (RegCounter <= R_EDI) Do
Begin
FillChar(RegInfo, SizeOf(RegInfo), 0);
RegInfo.NewRegsEncountered := [procinfo^.FramePointer, R_ESP];
RegInfo.OldRegsEncountered := RegInfo.NewRegsEncountered;
RegInfo.New2OldReg[procinfo^.FramePointer] := procinfo^.FramePointer;
RegInfo.New2OldReg[R_ESP] := R_ESP;
Found := 0;
hp2 := PPaiProp(PrevNonRemovablePai^.OptInfo)^.Regs[RegCounter].StartMod;
If (PrevNonRemovablePai <> PPaiProp(PrevNonRemovablePai^.OptInfo)^.Regs[RegCounter].StartMod)
Then OldNrOfMods := PPaiProp(PrevNonRemovablePai^.OptInfo)^.Regs[RegCounter].NrOfMods
Else OldNrOfMods := 1;
hp3 := p;
While (Found <> OldNrOfMods) And
{ old new }
InstructionsEquivalent(hp2, hp3, RegInfo) Do
Begin
GetNextInstruction(hp2, hp2);
GetNextInstruction(hp3, hp3);
Inc(Found)
End;
If (Found <> OldNrOfMods) Then
Begin
TmpResult := False;
If (found > 0) then
{this is correct because we only need to turn off the CanBeRemoved flag
when an instruction has already been processed by CheckSequence
(otherwise CanBeRemoved can't be true and thus can't have to be turned off).
If it has already been processed by CheckSequence and flagged to be
removed, it means that it has been checked against a previous sequence
and that it was equal (otherwise CheckSequence would have returned false
and the instruction wouldn't have been removed). If this "If found > 0"
check is left out, incorrect optimizations are performed.}
Found := PPaiProp(Pai(p)^.OptInfo)^.Regs[Reg].NrOfMods
End
Else TmpResult := True;
If TmpResult And
(Found > HighFound)
Then
Begin
HighFound := Found;
HighRegInfo := RegInfo;
End;
If (RegCounter = Reg) Then
Begin
OrgRegFound := Found;
OrgRegResult := TmpResult;
OrgRegInfo := RegInfo
End;
Repeat
Inc(RegCounter);
Until (RegCounter > R_EDI) or
((PPaiProp(PrevNonRemovablePai^.OptInfo)^.Regs[RegCounter].Typ = Con_Ref) {And
((Regcounter = Reg) Or
Not(PaiInSequence(p, PPaiProp(PrevNonRemovablePai^.OptInfo)^.Regs[RegCounter]))) }
);
End;
If (HighFound > 0) And
(Not(OrgRegResult) Or
(HighFound > OrgRegFound))
Then
Begin
{$ifndef fpc}
TmpResult := True;
{$else fpc}
CheckSequence := True;
{$endif fpc}
RegInfo := HighRegInfo;
Found := HighFound
End
Else
Begin
{$ifndef fpc}
TmpResult := OrgRegResult;
{$else fpc}
CheckSequence := OrgRegResult;
{$endif fpc}
Found := OrgRegFound;
RegInfo := OrgRegInfo;
End;
{ sometimes, registers in RegsLoadedForRef (which normally aren't/shouldn't }
{ be used anymore after the sequence, are still used nevertheless (when }
{ range checking is on for instance, because this is not "normal" generated }
{ code, but more or less manually inserted) }
{$ifndef fpc}
If TmpResult Then
{$else fpc}
If CheckSequence And (Found > 0) Then
{$endif fpc}
For RegCounter := R_EAX to R_EDI Do
If (RegCounter in RegInfo.RegsLoadedForRef) And
(RegInfo.New2OldReg[RegCounter] <> RegCounter) Then
Begin
OldNrOfMods := PPaiProp(PrevNonRemovablePai^.OptInfo)^.
Regs[RegInfo.New2OldReg[RegCounter]].NrOfMods;
hp2 := p;
For Cnt := 1 to Pred(OldNrOfMods) Do
GetNextInstruction(hp2, hp2);
{ hp2 now containts the last instruction of the sequence }
{ get the writestate at this point of the register in TmpState }
TmpState := PPaiProp(hp2^.OptInfo)^.Regs[RegCounter].WState;
{ now, even though reg is in RegsLoadedForRef, sometimes it's still used }
{ afterwards. It is not if either it is not in usedregs anymore after the }
{ sequence, or if it is loaded with a new value right after the sequence }
If GetNextInstruction(hp2, hp2) and
(TmpState = PPaiProp(hp2^.OptInfo)^.Regs[RegCounter].WState) And
(RegCounter in PPaiProp(hp2^.OptInfo)^.UsedRegs) Then
{ it is still used, so remove it from RegsLoadedForRef }
Begin
{$ifdef regrefdebug}
hp3 := new(pai_asm_comment,init(strpnew(att_reg2str[regcounter]+
' removed from regsloadedforref')));
hp3^.fileinfo := hp2^.fileinfo;
hp3^.next := hp2^.next;
hp3^.previous := hp2;
hp2^.next := hp3;
If assigned(hp3^.next) then
Pai(hp3^.next)^.previous := hp3;
{$endif regrefdebug}
Exclude(RegInfo.RegsLoadedForRef,RegCounter);
End;
End;
{$ifndef fpc}
CheckSequence := TmpResult;
{$endif fpc}
End; {CheckSequence}
Procedure AllocRegBetween(AsmL: PAasmOutput; Reg: TRegister; p1, p2: Pai);
{ allocates register Reg between (and including) instructions p1 and p2 }
{ the type of p1 and p2 must not be in SkipInstr }
var hp: pai;
Begin
If not(reg in usableregs+[R_EDI,R_ESI]) or
not(assigned(p1)) Then
{ this happens with registers which are loaded implicitely, outside the }
{ current block (e.g. esi with self) }
exit;
Repeat
If Assigned(p1^.OptInfo) Then
Include(PPaiProp(p1^.OptInfo)^.UsedRegs,Reg);
p1 := Pai(p1^.next);
Repeat
While assigned(p1) and
(p1^.typ in (SkipInstr-[ait_regalloc])) Do
p1 := Pai(p1^.next);
{ remove all allocation/deallocation info about the register in between }
If assigned(p1) and
(p1^.typ = ait_regalloc) Then
If (PaiRegAlloc(p1)^.Reg = Reg) Then
Begin
hp := Pai(p1^.Next);
AsmL^.Remove(p1);
Dispose(p1, Done);
p1 := hp;
End
Else p1 := Pai(p1^.next);
Until not(assigned(p1)) or
Not(p1^.typ in SkipInstr);
Until not(assigned(p1)) or
(p1 = p2);
End;
Procedure SetAlignReg(p: Pai);
Const alignSearch = 12;
var regsUsable: TRegSet;
prevInstrCount, nextInstrCount: Longint;
prevState, nextWState,nextRState: Array[R_EAX..R_EDI] of byte;
regCounter, lastRemoved: TRegister;
prev, next: Pai;
{$ifdef alignregdebug}
temp: Pai;
{$endif alignregdebug}
begin
regsUsable := [R_EAX,R_ECX,R_EDX,R_EBX,{R_ESP,R_EBP,}R_ESI,R_EDI];
for regCounter := R_EAX to R_EDI do
begin
prevState[regCounter] := PPaiProp(p^.optInfo)^.Regs[regCounter].wState;
nextWState[regCounter] := PPaiProp(p^.optInfo)^.Regs[regCounter].wState;
nextRState[regCounter] := PPaiProp(p^.optInfo)^.Regs[regCounter].rState;
end;
getLastInstruction(p,prev);
getNextInstruction(p,next);
lastRemoved := pai_align(p)^.reg;
nextInstrCount := 0;
prevInstrCount := 0;
while ((assigned(prev) and
assigned(prev^.optInfo) and
(prevInstrCount < alignSearch)) or
(assigned(next) and
assigned(next^.optInfo) and
(nextInstrCount < alignSearch))) And
(regsUsable <> []) do
begin
{$ifdef alignregdebug}
if assigned(prev) then
begin
temp := new(pai_asm_comment,init(strpnew('got here')));
temp^.next := prev^.next;
temp^.previous := prev;
prev^.next := temp;
if assigned(temp^.next) then
temp^.next^.previous := temp;
end;
{$endif alignregdebug}
if assigned(prev) and assigned(prev^.optinfo) and
(prevInstrCount < alignSearch) then
begin
if (prev^.typ = ait_instruction) And
(insProp[PaiCpu(prev)^.opcode].ch[1] <> Ch_ALL) and
(PaiCpu(prev)^.opcode <> A_JMP) then
begin
inc(prevInstrCount);
for regCounter := R_EAX to R_EDI do
begin
if (regCounter in regsUsable) And
(PPaiProp(prev^.optInfo)^.Regs[regCounter].wState <>
prevState[regCounter]) then
begin
lastRemoved := regCounter;
exclude(regsUsable,regCounter);
{$ifdef alignregdebug}
temp := new(pai_asm_comment,init(strpnew(
att_reg2str[regCounter]+' removed')));
temp^.next := prev^.next;
temp^.previous := prev;
prev^.next := temp;
if assigned(temp^.next) then
temp^.next^.previous := temp;
if regsUsable = [] then
begin
temp := new(pai_asm_comment,init(strpnew(
'regsUsable empty here')));
temp^.next := prev^.next;
temp^.previous := prev;
prev^.next := temp;
if assigned(temp^.next) then
temp^.next^.previous := temp;
end;
{$endif alignregdebug}
end;
prevState[regCounter] :=
PPaiProp(prev^.optInfo)^.Regs[regCounter].wState;
end;
getLastInstruction(prev,prev);
end
else
If GetLastInstruction(prev,prev) and
assigned(prev^.optinfo) then
for regCounter := R_EAX to R_EDI do
prevState[regCounter] :=
PPaiProp(prev^.optInfo)^.Regs[regCounter].wState
end;
if assigned(next) and assigned(next^.optInfo) and
(nextInstrCount < alignSearch) then
begin
if (next^.typ = ait_instruction) and
(insProp[PaiCpu(next)^.opcode].ch[1] <> Ch_ALL) and
(PaiCpu(next)^.opcode <> A_JMP) then
begin
inc(nextInstrCount);
for regCounter := R_EAX to R_EDI do
begin
if (regCounter in regsUsable) And
((PPaiProp(next^.optInfo)^.Regs[regCounter].wState <>
nextWState[regCounter]) or
(PPaiProp(next^.optInfo)^.Regs[regCounter].rState <>
nextRState[regCounter])) Then
begin
lastRemoved := regCounter;
exclude(regsUsable,regCounter);
{$ifdef alignregdebug}
temp := new(pai_asm_comment,init(strpnew(
att_reg2str[regCounter]+' removed')));
temp^.next := next^.next;
temp^.previous := next;
next^.next := temp;
if assigned(temp^.next) then
temp^.next^.previous := temp;
if regsUsable = [] then
begin
temp := new(pai_asm_comment,init(strpnew(
'regsUsable empty here')));
temp^.next := next^.next;
temp^.previous := next;
next^.next := temp;
if assigned(temp^.next) then
temp^.next^.previous := temp;
end;
{$endif alignregdebug}
end;
nextWState[regCounter] :=
PPaiProp(next^.optInfo)^.Regs[regCounter].wState;
nextRState[regCounter] :=
PPaiProp(next^.optInfo)^.Regs[regCounter].rState;
end
end
else
for regCounter := R_EAX to R_EDI do
begin
nextWState[regCounter] :=
PPaiProp(next^.optInfo)^.Regs[regCounter].wState;
nextRState[regCounter] :=
PPaiProp(next^.optInfo)^.Regs[regCounter].rState;
end;
getNextInstruction(next,next);
end;
end;
if regsUsable <> [] then
for regCounter := R_EAX to R_EDI do
if regCounter in regsUsable then
begin
lastRemoved := regCounter;
break
end;
{$ifdef alignregdebug}
next := new(pai_asm_comment,init(strpnew(att_reg2str[lastRemoved]+
' chosen as alignment register')));
next^.next := p^.next;
next^.previous := p;
p^.next := next;
if assigned(next^.next) then
next^.next^.previous := next;
{$endif alignregdebug}
pai_align(p)^.reg := lastRemoved;
End;
{$ifdef replacereg}
function FindRegDealloc(reg: tregister; p: pai): boolean;
{ assumes reg is a 32bit register }
begin
findregdealloc := false;
while assigned(p^.previous) and
((Pai(p^.previous)^.typ in (skipinstr+[ait_align])) or
((Pai(p^.previous)^.typ = ait_label) and
not(Pai_Label(p^.previous)^.l^.is_used))) do
begin
p := pai(p^.previous);
if (p^.typ = ait_regalloc) and
(pairegalloc(p)^.reg = reg) then
begin
findregdealloc := not(pairegalloc(p)^.allocation);
break;
end;
end
end;
Procedure RestoreRegContentsTo(reg: TRegister; const c: TContent; p, endP: pai);
var
{$ifdef replaceregdebug}
hp: pai;
{$endif replaceregdebug}
tmpState: byte;
begin
{$ifdef replaceregdebug}
hp := new(pai_asm_comment,init(strpnew(
'restored '+att_reg2str[reg]+' with data from here...')));
hp^.next := p;
hp^.previous := p^.previous;
p^.previous := hp;
if assigned(hp^.previous) then
hp^.previous^.next := hp;
{$endif replaceregdebug}
PPaiProp(p^.optInfo)^.Regs[reg] := c;
While (p <> endP) Do
Begin
PPaiProp(p^.optInfo)^.Regs[reg] := c;
getNextInstruction(p,p);
end;
tmpState := PPaiProp(p^.optInfo)^.Regs[reg].wState;
repeat
PPaiProp(p^.optInfo)^.Regs[reg] := c;
until not getNextInstruction(p,p) or
(PPaiProp(p^.optInfo)^.Regs[reg].wState <> tmpState);
{$ifdef replaceregdebug}
if assigned(p) then
begin
hp := new(pai_asm_comment,init(strpnew(
'restored '+att_reg2str[reg]+' till here...')));
hp^.next := p;
hp^.previous := p^.previous;
p^.previous := hp;
if assigned(hp^.previous) then
hp^.previous^.next := hp;
end;
{$endif replaceregdebug}
end;
Procedure ClearRegContentsFrom(reg: TRegister; p, endP: pai);
{ first clears the contents of reg from p till endP. Then the contents are }
{ cleared until the first instruction that changes reg }
var
{$ifdef replaceregdebug}
hp: pai;
{$endif replaceregdebug}
tmpState: byte;
begin
PPaiProp(p^.optInfo)^.Regs[reg].typ := con_unknown;
While (p <> endP) Do
Begin
PPaiProp(p^.optInfo)^.Regs[reg].typ := con_unknown;
getNextInstruction(p,p);
end;
tmpState := PPaiProp(p^.optInfo)^.Regs[reg].wState;
repeat
PPaiProp(p^.optInfo)^.Regs[reg].typ := con_unknown;
until not getNextInstruction(p,p) or
(PPaiProp(p^.optInfo)^.Regs[reg].wState <> tmpState);
{$ifdef replaceregdebug}
if assigned(p) then
begin
hp := new(pai_asm_comment,init(strpnew(
'cleared '+att_reg2str[reg]+' till here...')));
hp^.next := p;
hp^.previous := p^.previous;
p^.previous := hp;
if assigned(hp^.previous) then
hp^.previous^.next := hp;
end;
{$endif replaceregdebug}
end;
function NoHardCodedRegs(p: paicpu; orgReg, newReg: tRegister): boolean;
var chCount: byte;
begin
case p^.opcode of
A_IMUL: noHardCodedRegs := p^.ops <> 1;
A_SHL,A_SHR,A_SHLD,A_SHRD: noHardCodedRegs :=
(p^.oper[0].typ <> top_reg) or
((orgReg <> R_ECX) and (newReg <> R_ECX));
else
begin
NoHardCodedRegs := true;
with InsProp[p^.opcode] do
for chCount := 1 to MaxCh do
if Ch[chCount] in ([Ch_REAX..Ch_MEDI,Ch_WMemEDI,Ch_All]-[Ch_RESP,Ch_WESP,Ch_RWESP]) then
begin
NoHardCodedRegs := false;
break
end;
end;
end;
end;
Procedure ChangeReg(var Reg: TRegister; orgReg, newReg: TRegister);
begin
if reg = newReg then
reg := orgReg
else if reg = regtoreg8(newReg) then
reg := regtoreg8(orgReg)
else if reg = regtoreg16(newReg) then
reg := regtoreg16(orgReg);
end;
procedure changeOp(var o: toper; orgReg, newReg: tregister);
begin
case o.typ of
top_reg: changeReg(o.reg,orgReg,newReg);
top_ref:
begin
changeReg(o.ref^.base,orgReg,newReg);
changeReg(o.ref^.index,orgReg,newReg);
end;
end;
end;
Procedure DoReplaceReg(orgReg,newReg: tregister; hp: paicpu);
var opCount: byte;
begin
for opCount := 0 to 2 do
changeOp(hp^.oper[opCount],orgReg,newReg)
end;
function RegSizesOK(oldReg,newReg: TRegister; p: paicpu): boolean;
{ oldreg and newreg must be 32bit components }
var opCount: byte;
begin
RegSizesOK := true;
{ if only one of them is a general purpose register ... }
if (IsGP32reg(oldReg) xor IsGP32Reg(newReg)) then
begin
for opCount := 0 to 2 do
if (p^.oper[opCount].typ = top_reg) and
(p^.oper[opCount].reg in [R_AL..R_DH]) then
begin
RegSizesOK := false;
break
end
end;
end;
function RegReadByInstruction(reg: TRegister; hp: pai): boolean;
{ assumes hp doesn't modify registers implicitely (like div) }
{ and that reg is a 32bit register }
var p: paicpu;
opCount: byte;
begin
RegReadByInstruction := false;
p := paicpu(hp);
if hp^.typ <> ait_instruction then
exit;
case p^.opcode of
A_IMUL:
case p^.ops of
1: regReadByInstruction := (reg = R_EAX) or reginOp(reg,p^.oper[0]);
2,3:
regReadByInstruction := regInOp(reg,p^.oper[0]) or
regInOp(reg,p^.oper[1]);
end;
{ A_IDIV,A_DIV,A_IMUL:
begin
regReadByInstruction :=
regInOp(reg,p^.oper[0]) or
(((p^.opcode = A_IDIV) or
(p^.opcode = A_DIV)) and
(reg = R_EAX));
end;}
else
begin
for opCount := 0 to 2 do
if (p^.oper[opCount].typ = top_ref) and
RegInRef(reg,p^.oper[opCount].ref^) then
begin
RegReadByInstruction := true;
exit
end;
for opCount := 1 to MaxCh do
case InsProp[p^.opcode].Ch[opCount] of
Ch_RWOp1,Ch_ROp1{$ifdef arithopt},Ch_MOp1{$endif}:
if (p^.oper[0].typ = top_reg) and
(reg32(p^.oper[0].reg) = reg) then
begin
RegReadByInstruction := true;
exit
end;
Ch_RWOp2,Ch_ROp2{$ifdef arithopt},Ch_MOp2{$endif}:
if (p^.oper[1].typ = top_reg) and
(reg32(p^.oper[1].reg) = reg) then
begin
RegReadByInstruction := true;
exit
end;
Ch_RWOp3,Ch_ROp3{$ifdef arithopt},Ch_MOp3{$endif}:
if (p^.oper[2].typ = top_reg) and
(reg32(p^.oper[2].reg) = reg) then
begin
RegReadByInstruction := true;
exit
end;
end;
end;
end;
end;
procedure DoReplaceReadReg(orgReg,newReg: tregister; p: paicpu);
var opCount: byte;
begin
{ handle special case }
case p^.opcode of
A_IMUL:
begin
case p^.ops of
1: internalerror(1301001);
2,3:
begin
changeOp(p^.oper[0],orgReg,newReg);
if p^.ops = 3 then
changeOp(p^.oper[1],orgReg,newReg);
end;
end;
end;
A_DIV,A_IDIV,A_MUL: internalerror(1301002);
else
begin
for opCount := 0 to 2 do
if p^.oper[opCount].typ = top_ref then
changeOp(p^.oper[opCount],orgReg,newReg);
for opCount := 1 to MaxCh do
case InsProp[p^.opcode].Ch[opCount] of
Ch_ROp1:
if p^.oper[0].typ = top_reg then
ChangeReg(p^.oper[0].reg,orgReg,newReg);
Ch_ROp2:
if p^.oper[1].typ = top_reg then
ChangeReg(p^.oper[1].reg,orgReg,newReg);
Ch_ROp3:
if p^.oper[2].typ = top_reg then
ChangeReg(p^.oper[2].reg,orgReg,newReg);
end;
end;
end;
end;
function ReplaceReg(orgReg, newReg: TRegister; p: pai;
const c: TContent; orgRegCanBeModified: Boolean;
var returnEndP: pai): Boolean;
{ Tries to replace orgreg with newreg in all instructions coming after p }
{ until orgreg gets loaded with a new value. Returns true if successful, }
{ false otherwise. If successful, the contents of newReg are set to c, }
{ which should hold the contents of newReg before the current sequence }
{ started }
{ if the functino returns true, returnEndP holds the lat instruction }
{ where newReg was replaced by orgReg }
var endP, hp: Pai;
removeLast, sequenceEnd, tmpResult, newRegModified, orgRegRead: Boolean;
function storeBack(p1: pai): boolean;
{ returns true if p1 contains an instruction that stores the contents }
{ of newReg back to orgReg }
begin
storeBack :=
(p1^.typ = ait_instruction) and
(paicpu(p1)^.opcode = A_MOV) and
(paicpu(p1)^.oper[0].typ = top_reg) and
(paicpu(p1)^.oper[0].reg = newReg) and
(paicpu(p1)^.oper[1].typ = top_reg) and
(paicpu(p1)^.oper[1].reg = orgReg);
end;
begin
ReplaceReg := false;
tmpResult := true;
sequenceEnd := false;
newRegModified := false;
orgRegRead := false;
removeLast := false;
endP := p;
while tmpResult and not sequenceEnd do
begin
tmpResult :=
getNextInstruction(endP,endP) and
(endP^.typ = ait_instruction);
if tmpresult and not assigned(endP^.optInfo) then
begin
{ hp := new(pai_asm_comment,init(strpnew('next no optinfo')));
hp^.next := endp;
hp^.previous := endp^.previous;
endp^.previous := hp;
if assigned(hp^.previous) then
hp^.previous^.next := hp;}
exit;
end;
If tmpResult and
{ don't take into account instructions that will be removed }
Not (PPaiProp(endP^.optInfo)^.canBeRemoved) then
begin
{ if the newReg gets stored back to the oldReg, we can change }
{ "mov %oldReg,%newReg; <operations on %newReg>; mov %newReg, }
{ %oldReg" to "<operations on %oldReg>" }
removeLast := storeBack(endP);
sequenceEnd :=
removeLast or
{ no support for (i)div, mul and imul with hardcoded operands }
(noHardCodedRegs(paicpu(endP),orgReg,newReg) and
{ if newReg gets loaded with a new value, we can stop }
{ replacing newReg with oldReg here (possibly keeping }
{ the original contents of oldReg so we still know them }
{ afterwards) }
RegLoadedWithNewValue(newReg,true,paicpu(endP)) or
{ we can also stop if we reached the end of the use of }
{ newReg's current contents }
(GetNextInstruction(endp,hp) and
FindRegDealloc(newReg,hp)));
newRegModified :=
newRegModified or
(not(regLoadedWithNewValue(newReg,true,paicpu(endP))) and
RegModifiedByInstruction(newReg,endP));
orgRegRead := newRegModified and RegReadByInstruction(orgReg,endP);
sequenceEnd := SequenceEnd and
(removeLast or
{ since newReg will be replaced by orgReg, we can't allow that newReg }
{ gets modified if orgReg is still read afterwards (since after }
{ replacing, this would mean that orgReg first gets modified and then }
{ gets read in the assumption it still contains the unmodified value) }
not(newRegModified and orgRegRead)) (* and
{ since newReg will be replaced by orgReg, we can't allow that newReg }
{ gets modified if orgRegCanBeModified = false }
(orgRegCanBeModified or not(newRegModified)) *);
tmpResult :=
not(removeLast) and
not(newRegModified and orgRegRead) and
(* (orgRegCanBeModified or not(newRegModified)) and *)
(endP^.typ = ait_instruction) and
not(paicpu(endP)^.is_jmp) and
NoHardCodedRegs(paicpu(endP),orgReg,newReg) and
RegSizesOk(orgReg,newReg,paicpu(endP)) and
not RegModifiedByInstruction(orgReg,endP);
end;
end;
sequenceEnd := sequenceEnd and
(removeLast or
(orgRegCanBeModified or not(newRegModified))) and
(not(assigned(endp)) or
not(endp^.typ = ait_instruction) or
(noHardCodedRegs(paicpu(endP),orgReg,newReg) and
RegSizesOk(orgReg,newReg,paicpu(endP)) and
not(newRegModified and
(orgReg in PPaiProp(endP^.optInfo)^.usedRegs) and
not(RegLoadedWithNewValue(orgReg,true,paicpu(endP))))));
if SequenceEnd then
begin
{$ifdef replaceregdebug}
hp := new(pai_asm_comment,init(strpnew(
'replacing '+att_reg2str[newreg]+' with '+att_reg2str[orgreg]+
' from here...')));
hp^.next := p;
hp^.previous := p^.previous;
p^.previous := hp;
if assigned(hp^.previous) then
hp^.previous^.next := hp;
hp := new(pai_asm_comment,init(strpnew(
'replaced '+att_reg2str[newreg]+' with '+att_reg2str[orgreg]+
' till here')));
hp^.next := endp^.next;
hp^.previous := endp;
endp^.next := hp;
if assigned(hp^.next) then
hp^.next^.previous := hp;
{$endif replaceregdebug}
replaceReg := true;
returnEndP := endP;
getNextInstruction(p,hp);
while hp <> endP do
begin
if not(PPaiProp(hp^.optInfo)^.canBeRemoved) and
(hp^.typ = ait_instruction) then
DoReplaceReg(orgReg,newReg,paicpu(hp));
GetNextInstruction(hp,hp)
end;
if assigned(endp) and (endp^.typ = ait_instruction) then
DoReplaceReadReg(orgReg,newReg,paicpu(endP));
{ the replacing stops either at the moment that }
{ a) the newreg gets loaded with a new value (one not depending on the }
{ current value of newreg) }
{ b) newreg is completely replaced in this sequence and it's current value }
{ isn't used anymore }
{ In case b, the newreg was completely replaced by oldreg, so it's contents }
{ are unchanged compared the start of this sequence, so restore them }
If removeLast or
RegLoadedWithNewValue(newReg,true,endP) then
GetLastInstruction(endP,hp)
else hp := endP;
if removeLast or
(p <> endp) or
not RegLoadedWithNewValue(newReg,true,endP) then
RestoreRegContentsTo(newReg, c ,p, hp);
{ In both case a and b, it is possible that the new register was modified }
{ (e.g. an add/sub), so if it was replaced by oldreg in that instruction, }
{ oldreg's contents have been changed. To take this into account, we simply }
{ set the contents of orgreg to "unknown" after this sequence }
if newRegModified then
ClearRegContentsFrom(orgReg,p,hp);
if removeLast then
ppaiprop(endP^.optinfo)^.canBeRemoved := true;
end
{$ifdef replaceregdebug}
else
begin
hp := new(pai_asm_comment,init(strpnew(
'replacing '+att_reg2str[newreg]+' with '+att_reg2str[orgreg]+
' from here...')));
hp^.previous := p^.previous;
hp^.next := p;
p^.previous := hp;
if assigned(hp^.previous) then
hp^.previous^.next := hp;
hp := new(pai_asm_comment,init(strpnew(
'replacing '+att_reg2str[newreg]+' with '+att_reg2str[orgreg]+
' failed here')));
hp^.next := endp^.next;
hp^.previous := endp;
endp^.next := hp;
if assigned(hp^.next) then
hp^.next^.previous := hp;
end;
{$endif replaceregdebug}
End;
{$endif replacereg}
{$ifdef arithopt}
Function FindRegWithConst(p: Pai; size: topsize; l: longint; Var Res: TRegister): Boolean;
{Finds a register which contains the constant l}
Var Counter: TRegister;
{$ifdef testing}
hp: pai;
{$endif testing}
tmpresult: boolean;
Begin
Counter := R_NO;
repeat
inc(counter);
tmpresult := (PPaiProp(p^.OptInfo)^.Regs[Counter].Typ = Con_Const) and
(paicpu(PPaiProp(p^.OptInfo)^.Regs[Counter].StartMod)^.opsize = size) and
(paicpu(PPaiProp(p^.OptInfo)^.Regs[Counter].StartMod)^.oper[0].typ = top_const) and
(paicpu(PPaiProp(p^.OptInfo)^.Regs[Counter].StartMod)^.oper[0].val = l);
{$ifdef testing}
if (PPaiProp(p^.OptInfo)^.Regs[Counter].Typ = Con_Const) then
begin
hp := new(pai_asm_comment,init(strpnew(
'checking const load of '+tostr(l)+' here...')));
hp^.next := PPaiProp(p^.OptInfo)^.Regs[Counter].StartMod;
hp^.previous := PPaiProp(p^.OptInfo)^.Regs[Counter].StartMod^.previous;
PPaiProp(p^.OptInfo)^.Regs[Counter].StartMod^.previous := hp;
if assigned(hp^.previous) then
hp^.previous^.next := hp;
end;
{$endif testing}
until tmpresult or (Counter = R_EDI);
res := counter;
FindRegWithConst := tmpResult;
End;
{$endif arithopt}
Procedure DoCSE(AsmL: PAasmOutput; First, Last: Pai);
{marks the instructions that can be removed by RemoveInstructs. They're not
removed immediately because sometimes an instruction needs to be checked in
two different sequences}
Var Cnt, Cnt2: Longint;
p, hp1, hp2: Pai;
hp3, hp4: pai;
{$ifdef replacereg}
hp5 : pai;
{$else}
{$ifdef csdebug}
hp5 : pai;
{$endif}
{$endif}
RegInfo: TRegInfo;
RegCounter: TRegister;
TmpState: Byte;
Begin
p := First;
SkipHead(p);
First := p;
While (p <> Last) Do
Begin
Case p^.typ Of
ait_align:
if not(pai_align(p)^.use_op) then
SetAlignReg(p);
ait_instruction:
Begin
Case Paicpu(p)^.opcode Of
A_CLD: If GetLastInstruction(p, hp1) And
(PPaiProp(hp1^.OptInfo)^.DirFlag = F_NotSet) Then
PPaiProp(Pai(p)^.OptInfo)^.CanBeRemoved := True;
A_MOV, A_MOVZX, A_MOVSX:
Begin
Case Paicpu(p)^.oper[0].typ Of
Top_Ref:
Begin {destination is always a register in this case}
With PPaiProp(p^.OptInfo)^.Regs[Reg32(Paicpu(p)^.oper[1].reg)] Do
Begin
If (p = StartMod) And
GetLastInstruction (p, hp1) And
(hp1^.typ <> ait_marker)
Then
{so we don't try to check a sequence when p is the first instruction of the block}
If CheckSequence(p, Paicpu(p)^.oper[1].reg, Cnt, RegInfo) And
(Cnt > 0) Then
Begin
hp1 := nil;
{ although it's perfectly ok to remove an instruction which doesn't contain }
{ the register that we've just checked (CheckSequence takes care of that), }
{ the sequence containing this other register should also be completely }
{ checked and removed, otherwise we may get situations like this: }
{ }
{ movl 12(%ebp), %edx movl 12(%ebp), %edx }
{ movl 16(%ebp), %eax movl 16(%ebp), %eax }
{ movl 8(%edx), %edx movl 8(%edx), %edx }
{ movl (%eax), eax movl (%eax), eax }
{ cmpl %eax, %edx cmpl %eax, %edx }
{ jnz l123 getting converted to jnz l123 }
{ movl 12(%ebp), %edx movl 4(%eax), eax }
{ movl 16(%ebp), %eax }
{ movl 8(%edx), %edx }
{ movl 4(%eax), eax }
hp2 := p;
Cnt2 := 1;
While Cnt2 <= Cnt Do
Begin
If (hp1 = nil) And
Not(RegInInstruction(Paicpu(hp2)^.oper[1].reg, p) Or
RegInInstruction(Reg32(Paicpu(hp2)^.oper[1].reg), p)) And
Not((p^.typ = ait_instruction) And
(paicpu(p)^.OpCode = A_MOV) And
(paicpu(p)^.Oper[0].typ = top_ref) And
(PPaiProp(p^.OptInfo)^.Regs[Reg32(paicpu(p)^.Oper[1].reg)].NrOfMods
<= (Cnt - Cnt2 + 1)))
Then hp1 := p;
{$ifndef noremove}
PPaiProp(p^.OptInfo)^.CanBeRemoved := True;
{$endif noremove}
Inc(Cnt2);
GetNextInstruction(p, p);
End;
hp3 := New(Pai_Marker,Init(NoPropInfoStart));
InsertLLItem(AsmL, Pai(hp2^.Previous), hp2, hp3);
{hp4 is used to get the contents of the registers before the sequence}
GetLastInstruction(hp2, hp4);
{$IfDef CSDebug}
For RegCounter := R_EAX To R_EDI Do
If (RegCounter in RegInfo.RegsLoadedForRef) Then
Begin
hp5 := new(pai_asm_comment,init(strpnew('New: '+att_reg2str[RegCounter]+', Old: '+
att_reg2str[RegInfo.New2OldReg[RegCounter]])));
InsertLLItem(AsmL, Pai(hp2^.previous), hp2, hp5);
End;
{$EndIf CSDebug}
{ If some registers were different in the old and the new sequence, move }
{ the contents of those old registers to the new ones }
For RegCounter := R_EAX To R_EDI Do
If Not(RegCounter in [R_ESP,procinfo^.framepointer]) And
(RegInfo.New2OldReg[RegCounter] <> R_NO) Then
Begin
AllocRegBetween(AsmL,RegInfo.New2OldReg[RegCounter],
PPaiProp(hp4^.OptInfo)^.Regs[RegInfo.New2OldReg[RegCounter]].StartMod,hp2);
If Not(RegCounter In RegInfo.RegsLoadedForRef) And
{old reg new reg}
(RegInfo.New2OldReg[RegCounter] <> RegCounter) Then
Begin
{$ifdef replacereg}
getLastInstruction(p,hp3);
If not ReplaceReg(RegInfo.New2OldReg[RegCounter],
regCounter,hp3,
PPaiProp(hp4^.optInfo)^.Regs[regCounter],true,hp5) then
begin
{$endif replacereg}
hp3 := New(Paicpu,Op_Reg_Reg(A_MOV, S_L,
{old reg new reg}
RegInfo.New2OldReg[RegCounter], RegCounter));
InsertLLItem(AsmL, Pai(hp2^.previous), hp2, hp3);
{$ifdef replacereg}
end
{$endif replacereg}
End
Else
{ imagine the following code: }
{ normal wrong optimized }
{ movl 8(%ebp), %eax movl 8(%ebp), %eax }
{ movl (%eax), %eax movl (%eax), %eax }
{ cmpl 8(%ebp), %eax cmpl 8(%ebp), %eax }
{ jne l1 jne l1 }
{ movl 8(%ebp), %eax }
{ movl (%eax), %edi movl %eax, %edi }
{ movl %edi, -4(%ebp) movl %edi, -4(%ebp) }
{ movl 8(%ebp), %eax }
{ pushl 70(%eax) pushl 70(%eax) }
{ }
{ The error is that at the moment that the last instruction is executed, }
{ %eax doesn't contain 8(%ebp) anymore. Solution: the contents of }
{ registers that are completely removed from a sequence (= registers in }
{ RegLoadedForRef, have to be changed to their contents from before the }
{ sequence. }
If RegCounter in RegInfo.RegsLoadedForRef Then
Begin
{load Cnt2 with the total number of instructions of this sequence}
Cnt2 := PPaiProp(hp4^.OptInfo)^.
Regs[RegInfo.New2OldReg[RegCounter]].NrOfMods;
hp3 := hp2;
For Cnt := 1 to Pred(Cnt2) Do
GetNextInstruction(hp3, hp3);
TmpState := PPaiProp(hp3^.OptInfo)^.Regs[RegCounter].WState;
GetNextInstruction(hp3, hp3);
{$ifdef csdebug}
Writeln('Cnt2: ',Cnt2);
hp5 := new(pai_asm_comment,init(strpnew('starting here...')));
InsertLLItem(AsmL, Pai(hp2^.previous), hp2, hp5);
{$endif csdebug}
hp3 := hp2;
{first change the contents of the register inside the sequence}
For Cnt := 1 to Cnt2 Do
Begin
{save the WState of the last pai object of the sequence for later use}
TmpState := PPaiProp(hp3^.OptInfo)^.Regs[RegCounter].WState;
{$ifdef csdebug}
hp5 := new(pai_asm_comment,init(strpnew('WState for '+att_reg2str[Regcounter]+': '
+tostr(tmpstate))));
InsertLLItem(AsmL, hp3, pai(hp3^.next), hp5);
{$endif csdebug}
PPaiProp(hp3^.OptInfo)^.Regs[RegCounter] :=
PPaiProp(hp4^.OptInfo)^.Regs[RegCounter];
GetNextInstruction(hp3, hp3);
End;
{here, hp3 = p = Pai object right after the sequence, TmpState = WState of
RegCounter at the last Pai object of the sequence}
GetLastInstruction(hp3, hp3);
While GetNextInstruction(hp3, hp3) And
(PPaiProp(hp3^.OptInfo)^.Regs[RegCounter].WState
= TmpState) Do
{$ifdef csdebug}
begin
hp5 := new(pai_asm_comment,init(strpnew('WState for '+att_reg2str[Regcounter]+': '+
tostr(PPaiProp(hp3^.OptInfo)^.Regs[RegCounter].WState))));
InsertLLItem(AsmL, hp3, pai(hp3^.next), hp5);
{$endif csdebug}
PPaiProp(hp3^.OptInfo)^.Regs[RegCounter] :=
PPaiProp(hp4^.OptInfo)^.Regs[RegCounter];
{$ifdef csdebug}
end;
{$endif csdebug}
{$ifdef csdebug}
hp5 := new(pai_asm_comment,init(strpnew('stopping here...')));
InsertLLItem(AsmL, hp3, pai(hp3^.next), hp5);
{$endif csdebug}
End;
End;
hp3 := New(Pai_Marker,Init(NoPropInfoEnd));
InsertLLItem(AsmL, Pai(hp2^.Previous), hp2, hp3);
If hp1 <> nil Then p := hp1;
Continue;
End
Else
If (Cnt > 0) And
(PPaiProp(p^.OptInfo)^.
Regs[Reg32(Paicpu(p)^.oper[1].reg)].Typ = Con_Ref) And
(PPaiProp(p^.OptInfo)^.CanBeRemoved) Then
Begin
hp2 := p;
Cnt2 := 1;
While Cnt2 <= Cnt Do
Begin
If RegInInstruction(Paicpu(hp2)^.oper[1].reg, p) Or
RegInInstruction(Reg32(Paicpu(hp2)^.oper[1].reg), p) Then
PPaiProp(p^.OptInfo)^.CanBeRemoved := False;
Inc(Cnt2);
GetNextInstruction(p, p);
End;
Continue;
End;
End;
End;
{$ifdef replacereg}
top_Reg:
{ try to replace the new reg with the old reg }
if not(PPaiProp(p^.optInfo)^.canBeRemoved) and
(paicpu(p)^.opcode = A_MOV) and
getLastInstruction(p,hp4) then
begin
case paicpu(p)^.oper[1].typ of
top_Reg:
{ we only have to start replacing from the instruction after the mov, }
{ but replacereg only starts with getnextinstruction(p,p) }
if ReplaceReg(paicpu(p)^.oper[0].reg,
paicpu(p)^.oper[1].reg,p,
PPaiProp(hp4^.optInfo)^.Regs[paicpu(p)^.oper[1].reg],false,hp1) then
begin
PPaiProp(p^.optInfo)^.canBeRemoved := true;
allocRegBetween(asmL,paicpu(p)^.oper[0].reg,
PPaiProp(p^.optInfo)^.regs[paicpu(p)^.oper[0].reg].startMod,
hp1);
end;
end
end;
{$endif replacereg}
top_symbol,Top_Const:
Begin
Case Paicpu(p)^.oper[1].typ Of
Top_Reg:
Begin
regCounter := Reg32(Paicpu(p)^.oper[1].reg);
If GetLastInstruction(p, hp1) Then
With PPaiProp(hp1^.OptInfo)^.Regs[regCounter] Do
If (Typ = Con_Const) And
(paicpu(startMod)^.opsize >= paicpu(p)^.opsize) and
opsequal(paicpu(StartMod)^.oper[0],paicpu(p)^.oper[0]) Then
begin
PPaiProp(p^.OptInfo)^.CanBeRemoved := True;
allocRegBetween(asmL,regCounter,startMod,p);
end;
End;
{$ifdef arithopt}
Top_Ref:
if (paicpu(p)^.oper[0].typ = top_const) and
getLastInstruction(p,hp1) and
findRegWithConst(hp1,paicpu(p)^.opsize,paicpu(p)^.oper[0].val,regCounter) then
begin
paicpu(p)^.loadreg(0,regCounter);
allocRegBetween(AsmL,reg32(regCounter),
PPaiProp(hp1^.optinfo)^.regs[regCounter].startMod,p);
end;
{$endif arithopt}
End;
End;
End;
End;
A_STD: If GetLastInstruction(p, hp1) And
(PPaiProp(hp1^.OptInfo)^.DirFlag = F_Set) Then
PPaiProp(Pai(p)^.OptInfo)^.CanBeRemoved := True;
End
End;
End;
GetNextInstruction(p, p);
End;
End;
Procedure RemoveInstructs(AsmL: PAasmOutput; First, Last: Pai);
{ Removes the marked instructions and disposes the PPaiProps of the other }
{ instructions }
Var p, hp1: Pai;
begin
p := First;
While (p <> Last) Do
Begin
If (p^.typ = ait_marker) and
(pai_marker(p)^.kind in [noPropInfoStart,noPropInfoEnd]) then
begin
hp1 := pai(p^.next);
asmL^.remove(p);
dispose(p,done);
p := hp1
end
else
{$ifndef noinstremove}
if assigned(p^.optInfo) and
PPaiProp(p^.optInfo)^.canBeRemoved then
begin
{$IfDef TP}
Dispose(PPaiProp(p^.OptInfo));
{$EndIf}
hp1 := pai(p^.next);
AsmL^.Remove(p);
Dispose(p, Done);
p := hp1;
End
Else
{$endif noinstremove}
Begin
{$IfDef TP}
if assigned(p^.optInfo) then
Dispose(PPaiProp(p^.OptInfo));
{$EndIf TP}
p^.OptInfo := nil;
p := pai(p^.next);;
End;
End;
{$IfNDef TP}
FreeMem(PaiPropBlock, NrOfPaiObjs*(((SizeOf(TPaiProp)+3)div 4)*4))
{$EndIf TP}
End;
Procedure CSE(AsmL: PAasmOutput; First, Last: Pai);
Begin
DoCSE(AsmL, First, Last);
RemoveInstructs(AsmL, First, Last);
End;
End.
{
$Log$
Revision 1.54 2000-02-24 18:41:38 peter
* removed warnings/notes
Revision 1.53 2000/02/19 13:50:29 jonas
* fixed bug in -dnewoptizations (showed itself only if -Or was
used as well I think)
Revision 1.52 2000/02/17 07:46:49 jonas
* -dreplacereg no logner tries to optimize "movl %reg1,%reg1" (which are
always marked as CanBeRemoved)
+ some comments in -dreplacereg code
* small fix which could cause crash when optimizer is compiler with -dTP
Revision 1.51 2000/02/12 19:28:56 jonas
* fix for imul optimization in popt386 (exclude top_ref as first
argument)
* in csopt386: change "mov reg1,reg2; <several operations on reg2>;
mov reg2,reg1" to "<several operations on reg1>" (-dnewopt...)
Revision 1.50 2000/02/12 14:10:14 jonas
+ change "mov reg1,reg2;imul x,reg2" to "imul x,reg1,reg2" in popt386
(-dnewoptimizations)
* shl(d) and shr(d) are considered to have a hardcoded register if
they use cl as shift count (since you can't replace them with
another register) in csopt386 (also for -dnewoptimizations)
Revision 1.49 2000/02/12 10:54:18 jonas
* fixed edi allocation in allocRegBetween
* fixed bug I introduced yesterday, added comment to prevent it from
happening again in the future
Revision 1.48 2000/02/11 23:50:03 jonas
* fixed crashing bug under Dos with -dnewoptimizations (found it,
John!). Don't understand why it didn't crash under Linux :(
Revision 1.47 2000/02/10 16:04:43 jonas
* fixed stupid typo!
Revision 1.46 2000/02/10 15:07:41 jonas
* fixed small bug introduced with my previous fix
Revision 1.45 2000/02/10 14:57:13 jonas
* fixed bug due to lack of support for top_symbol operands
Revision 1.44 2000/02/09 13:22:51 peter
* log truncated
Revision 1.43 2000/02/04 13:52:17 jonas
* better support for regvars (still needs a move of the call to the optimize
procedure to a place where resetusableregisters is not yet called to work)
* small regallocation fixes for -dnewoptimizations
Revision 1.42 2000/01/28 15:15:31 jonas
* moved skipinstr from daopt386 to aasm
* fixed crashing bug with -dreplacereg in csopt386.pas
Revision 1.41 2000/01/23 11:11:37 michael
+ Fixes from Jonas.
Revision 1.40 2000/01/22 16:10:06 jonas
+ all code generator generated "mov reg1,reg2" instructions are now
attempted to be removed using the replacereg code
(-dnewoptimizations)
* small fixes to -dreplacereg code
Revision 1.39 2000/01/13 13:07:05 jonas
* released -dalignreg
* some small fixes to -dnewOptimizations helper procedures
Revision 1.38 2000/01/07 01:14:23 peter
* updated copyright to 2000
Revision 1.37 2000/01/03 17:11:17 jonas
* fixed bug with -dreplacereg
Revision 1.36 1999/12/05 16:48:43 jonas
* CSE of constant loading in regs works properly again
+ if a constant is stored into memory using "mov const, ref" and
there is a reg that contains this const, it is changed into
"mov reg, ref"
Revision 1.35 1999/12/02 11:26:41 peter
* newoptimizations define added
Revision 1.34 1999/11/21 13:09:41 jonas
* fixed some missed optimizations because 8bit regs were not always
taken into account
Revision 1.33 1999/11/20 11:37:03 jonas
* make cycle works with -dreplacereg (register renaming)! I have not
tested it yet together with -darithopt, but I don't expect problems
Revision 1.32 1999/11/14 11:26:53 jonas
+ basic register renaming (not yet working completely, between
-dreplacereg/-dreplaceregdebug)
Revision 1.31 1999/11/06 16:21:57 jonas
+ search optimial register to use in alignment code (compile with
-dalignreg, -dalignregdebug to see chosen register in
assembler code). Still needs support in ag386bin.
Revision 1.30 1999/11/06 14:34:20 peter
* truncated log to 20 revs
Revision 1.29 1999/11/05 16:01:46 jonas
+ first implementation of choosing least used register for alignment code
(not yet working, between ifdef alignreg)
Revision 1.28 1999/10/11 11:11:31 jonas
* fixed bug which sometimes caused a crash when optimizing blocks of code with
assembler blocks (didn't notice before because of lack of zero page protection
under Win9x :( )
Revision 1.27 1999/10/01 13:51:40 jonas
* CSE now updates the RegAlloc's
Revision 1.26 1999/09/30 14:43:13 jonas
* fixed small efficiency which caused some missed optimizations (saves 1
assembler instruction on the whole compiler/RTL source tree! :)
Revision 1.25 1999/09/27 23:44:50 peter
* procinfo is now a pointer
* support for result setting in sub procedure
Revision 1.24 1999/08/25 11:59:58 jonas
* changed pai386, paippc and paiapha (same for tai*) to paicpu (taicpu)
}