* ported part of the i386 peep hole optimizer to x86-64 to see if it is possible to create a shared x86 peep hole optimizer

git-svn-id: trunk@20874 -
This commit is contained in:
florian 2012-04-14 19:08:02 +00:00
parent 931a0f159c
commit d24b70d22b

View File

@ -25,17 +25,321 @@ unit aoptcpu;
{$i fpcdefs.inc}
Interface
interface
uses
cpubase, aoptobj, aoptcpub, aopt;
uses cpubase, aasmtai, aopt, aoptcpub;
Type
TCpuAsmOptimizer = class(TAsmOptimizer)
End;
type
TCpuAsmOptimizer = class(TAsmOptimizer)
function PeepHoleOptPass1Cpu(var p: tai): boolean; override;
end;
Implementation
implementation
uses
globtype, globals,
cutils,
verbose,
cgbase, cgutils,
aasmbase, aasmdata, aasmcpu;
function isFoldableArithOp(hp1: taicpu; reg: tregister): boolean;
begin
isFoldableArithOp := False;
case hp1.opcode of
A_ADD, A_SUB, A_OR, A_XOR, A_AND, A_SHL, A_SHR, A_SAR:
isFoldableArithOp :=
((taicpu(hp1).oper[0]^.typ = top_const) or
((taicpu(hp1).oper[0]^.typ = top_reg) and
(taicpu(hp1).oper[0]^.reg<>reg))) and
(taicpu(hp1).oper[1]^.typ = top_reg) and
(taicpu(hp1).oper[1]^.reg = reg);
A_INC, A_DEC:
isFoldableArithOp :=
(taicpu(hp1).oper[0]^.typ = top_reg) and
(taicpu(hp1).oper[0]^.reg = reg);
end;
end;
function TCpuAsmOptimizer.PeepHoleOptPass1Cpu(var p: tai): boolean;
var
next1: tai;
hp1, hp2: tai;
begin
Result := False;
case p.typ of
ait_instruction:
begin
case taicpu(p).opcode of
A_AND:
begin
if (taicpu(p).oper[0]^.typ = top_const) and
(taicpu(p).oper[1]^.typ = top_reg) and
GetNextInstruction(p, hp1) and
(tai(hp1).typ = ait_instruction) and
(taicpu(hp1).opcode = A_AND) and
(taicpu(hp1).oper[0]^.typ = top_const) and
(taicpu(hp1).oper[1]^.typ = top_reg) and
(getsupreg(taicpu(p).oper[1]^.reg) = getsupreg(
taicpu(hp1).oper[1]^.reg)) and
(getsubreg(taicpu(p).oper[1]^.reg)<=getsubreg(
taicpu(hp1).oper[1]^.reg)) and
(abs(taicpu(p).oper[0]^.val and
taicpu(hp1).oper[0]^.val)<$80000000) then
{change "and const1, reg; and const2, reg" to "and (const1 and const2), reg"}
begin
taicpu(hp1).loadConst(0, taicpu(p).oper[0]^.val and
taicpu(hp1).oper[0]^.val);
asml.remove(p);
p.Free;
p := hp1;
end;
(* else
{change "and x, reg; jxx" to "test x, reg", if reg is deallocated before the
jump, but only if it's a conditional jump (PFV) }
if (taicpu(p).oper[1]^.typ = top_reg) and
GetNextInstruction(p, hp1) and
(hp1.typ = ait_instruction) and
(taicpu(hp1).is_jmp) and
(taicpu(hp1).opcode<>A_JMP) and
not(getsupreg(taicpu(p).oper[1]^.reg) in UsedRegs) then
taicpu(p).opcode := A_TEST;*)
end;
A_MOVSX,
A_MOVZX:
begin
if (taicpu(p).oper[1]^.typ = top_reg) and
GetNextInstruction(p, hp1) and
(hp1.typ = ait_instruction) and
IsFoldableArithOp(taicpu(hp1), taicpu(p).oper[1]^.reg) and
GetNextInstruction(hp1, hp2) and
(hp2.typ = ait_instruction) and
(taicpu(hp2).opcode = A_MOV) and
(taicpu(hp2).oper[0]^.typ = top_reg) and
OpsEqual(taicpu(hp2).oper[1]^, taicpu(p).oper[0]^) then
{ change movsX/movzX reg/ref, reg2 }
{ add/sub/or/... reg3/$const, reg2 }
{ mov reg2 reg/ref }
{ to add/sub/or/... reg3/$const, reg/ref }
begin
{ by example:
movswl %si,%eax movswl %si,%eax p
decl %eax addl %edx,%eax hp1
movw %ax,%si movw %ax,%si hp2
->
movswl %si,%eax movswl %si,%eax p
decw %eax addw %edx,%eax hp1
movw %ax,%si movw %ax,%si hp2
}
taicpu(hp1).changeopsize(taicpu(hp2).opsize);
{
->
movswl %si,%eax movswl %si,%eax p
decw %si addw %dx,%si hp1
movw %ax,%si movw %ax,%si hp2
}
case taicpu(hp1).ops of
1:
taicpu(hp1).loadoper(0, taicpu(hp2).oper[1]^);
2:
begin
taicpu(hp1).loadoper(1, taicpu(hp2).oper[1]^);
if (taicpu(hp1).oper[0]^.typ = top_reg) then
setsubreg(taicpu(hp1).oper[0]^.reg,
getsubreg(taicpu(hp2).oper[0]^.reg));
end;
else
internalerror(2008042701);
end;
{
->
decw %si addw %dx,%si p
}
asml.remove(p);
asml.remove(hp2);
p.Free;
hp2.Free;
p := hp1;
end
{ removes superfluous And's after movzx's }
else if taicpu(p).opcode = A_MOVZX then
begin
if (taicpu(p).oper[1]^.typ = top_reg) and
GetNextInstruction(p, hp1) and
(tai(hp1).typ = ait_instruction) and
(taicpu(hp1).opcode = A_AND) and
(taicpu(hp1).oper[0]^.typ = top_const) and
(taicpu(hp1).oper[1]^.typ = top_reg) and
(taicpu(hp1).oper[1]^.reg = taicpu(p).oper[1]^.reg) then
case taicpu(p).opsize of
S_BL, S_BW, S_BQ:
if (taicpu(hp1).oper[0]^.val = $ff) then
begin
asml.remove(hp1);
hp1.Free;
end;
S_WL, S_WQ:
if (taicpu(hp1).oper[0]^.val = $ffff) then
begin
asml.remove(hp1);
hp1.Free;
end;
S_LQ:
if (taicpu(hp1).oper[0]^.val = $ffffffff) then
begin
asml.remove(hp1);
hp1.Free;
end;
end;
{ changes some movzx constructs to faster synonims (all examples
are given with eax/ax, but are also valid for other registers)}
if (taicpu(p).oper[1]^.typ = top_reg) then
if (taicpu(p).oper[0]^.typ = top_reg) then
case taicpu(p).opsize of
S_BW:
begin
if (getsupreg(taicpu(p).oper[0]^.reg) =
getsupreg(taicpu(p).oper[1]^.reg)) and not
(cs_opt_size in current_settings.optimizerswitches) then
{Change "movzbw %al, %ax" to "andw $0x0ffh, %ax"}
begin
taicpu(p).opcode := A_AND;
taicpu(p).changeopsize(S_W);
taicpu(p).loadConst(0, $ff);
end
else if GetNextInstruction(p, hp1) and
(tai(hp1).typ = ait_instruction) and
(taicpu(hp1).opcode = A_AND) and
(taicpu(hp1).oper[0]^.typ = top_const) and
(taicpu(hp1).oper[1]^.typ = top_reg) and
(taicpu(hp1).oper[1]^.reg =
taicpu(p).oper[1]^.reg) then
{ Change "movzbw %reg1, %reg2; andw $const, %reg2"
to "movw %reg1, reg2; andw $(const1 and $ff), %reg2"}
begin
taicpu(p).opcode := A_MOV;
taicpu(p).changeopsize(S_W);
setsubreg(taicpu(p).oper[0]^.reg, R_SUBW);
taicpu(hp1).loadConst(
0, taicpu(hp1).oper[0]^.val and $ff);
end;
end;
S_BL:
begin
if (getsupreg(taicpu(p).oper[0]^.reg) =
getsupreg(taicpu(p).oper[1]^.reg)) and not
(cs_opt_size in current_settings.optimizerswitches) then
{ Change "movzbl %al, %eax" to "andl $0x0ffh, %eax"}
begin
taicpu(p).opcode := A_AND;
taicpu(p).changeopsize(S_L);
taicpu(p).loadConst(0, $ff);
end
else if GetNextInstruction(p, hp1) and
(tai(hp1).typ = ait_instruction) and
(taicpu(hp1).opcode = A_AND) and
(taicpu(hp1).oper[0]^.typ = top_const) and
(taicpu(hp1).oper[1]^.typ = top_reg) and
(taicpu(hp1).oper[1]^.reg =
taicpu(p).oper[1]^.reg) then
{ Change "movzbl %reg1, %reg2; andl $const, %reg2"
to "movl %reg1, reg2; andl $(const1 and $ff), %reg2"}
begin
taicpu(p).opcode := A_MOV;
taicpu(p).changeopsize(S_L);
setsubreg(taicpu(p).oper[0]^.reg, R_SUBWHOLE);
taicpu(hp1).loadConst(
0, taicpu(hp1).oper[0]^.val and $ff);
end;
end;
S_WL:
begin
if (getsupreg(taicpu(p).oper[0]^.reg) =
getsupreg(taicpu(p).oper[1]^.reg)) and not
(cs_opt_size in current_settings.optimizerswitches) then
{ Change "movzwl %ax, %eax" to "andl $0x0ffffh, %eax" }
begin
taicpu(p).opcode := A_AND;
taicpu(p).changeopsize(S_L);
taicpu(p).loadConst(0, $ffff);
end
else if GetNextInstruction(p, hp1) and
(tai(hp1).typ = ait_instruction) and
(taicpu(hp1).opcode = A_AND) and
(taicpu(hp1).oper[0]^.typ = top_const) and
(taicpu(hp1).oper[1]^.typ = top_reg) and
(taicpu(hp1).oper[1]^.reg =
taicpu(p).oper[1]^.reg) then
{ Change "movzwl %reg1, %reg2; andl $const, %reg2"
to "movl %reg1, reg2; andl $(const1 and $ffff), %reg2"}
begin
taicpu(p).opcode := A_MOV;
taicpu(p).changeopsize(S_L);
setsubreg(taicpu(p).oper[0]^.reg, R_SUBWHOLE);
taicpu(hp1).loadConst(
0, taicpu(hp1).oper[0]^.val and $ffff);
end;
end;
end
else if (taicpu(p).oper[0]^.typ = top_ref) then
begin
if GetNextInstruction(p, hp1) and
(tai(hp1).typ = ait_instruction) and
(taicpu(hp1).opcode = A_AND) and
(taicpu(hp1).oper[0]^.typ = Top_Const) and
(taicpu(hp1).oper[1]^.typ = Top_Reg) and
(taicpu(hp1).oper[1]^.reg =
taicpu(p).oper[1]^.reg) then
begin
taicpu(p).opcode := A_MOV;
case taicpu(p).opsize of
S_BL:
begin
taicpu(p).changeopsize(S_L);
taicpu(hp1).loadConst(
0, taicpu(hp1).oper[0]^.val and $ff);
end;
S_WL:
begin
taicpu(p).changeopsize(S_L);
taicpu(hp1).loadConst(
0, taicpu(hp1).oper[0]^.val and $ffff);
end;
S_BW:
begin
taicpu(p).changeopsize(S_W);
taicpu(hp1).loadConst(
0, taicpu(hp1).oper[0]^.val and $ff);
end;
S_BQ:
begin
taicpu(p).changeopsize(S_Q);
taicpu(hp1).loadConst(
0, taicpu(hp1).oper[0]^.val and $ff);
end;
S_WQ:
begin
taicpu(p).changeopsize(S_Q);
taicpu(hp1).loadConst(
0, taicpu(hp1).oper[0]^.val and $ffff);
end;
S_LQ:
begin
taicpu(p).changeopsize(S_Q);
taicpu(hp1).loadConst(
0, taicpu(hp1).oper[0]^.val and $ffffffff);
end;
end;
end;
end;
end;
end;
end;
end;
end;
end;
begin
casmoptimizer:=TCpuAsmOptimizer;
casmoptimizer := TCpuAsmOptimizer;
end.