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* adapt optimizer to handle push/pop for stack alignment

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* adapt test

git-svn-id: trunk@45477 -
This commit is contained in:
florian 2020-05-23 17:50:14 +00:00
parent 8f0a3cfce7
commit 809fb83334
3 changed files with 77 additions and 19 deletions
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92
compiler/x86/aoptx86.pas
View File

@ -73,6 +73,8 @@ unit aoptx86;
}
function GetNextInstructionUsingRegTrackingUse(Current: tai; out Next: tai; reg: TRegister): Boolean;
function RegModifiedByInstruction(Reg: TRegister; p1: tai): boolean; override;
private
function SkipSimpleInstructions(var hp1: tai): Boolean;
protected
class function IsMOVZXAcceptable: Boolean; static; inline;
@ -149,6 +151,7 @@ unit aoptx86;
function PostPeepholeOptTestOr(var p : tai) : Boolean;
function PostPeepholeOptCall(var p : tai) : Boolean;
function PostPeepholeOptLea(var p : tai) : Boolean;
function PostPeepholeOptPush(var p: tai): Boolean;
procedure ConvertJumpToRET(const p: tai; const ret_p: tai);
@ -5739,25 +5742,26 @@ unit aoptx86;
end;
function TX86AsmOptimizer.PostPeepholeOptLea(var p : tai) : Boolean;
function TX86AsmOptimizer.SkipSimpleInstructions(var hp1 : tai) : Boolean;
begin
{ we can skip all instructions not messing with the stack pointer }
while assigned(hp1) and {MatchInstruction(taicpu(hp1),[A_LEA,A_MOV,A_MOVQ,A_MOVSQ,A_MOVSX,A_MOVSXD,A_MOVZX,
A_AND,A_OR,A_XOR,A_ADD,A_SHR,A_SHL,A_IMUL,A_SETcc,A_SAR,A_SUB,A_TEST,A_CMOVcc,
A_MOVSS,A_MOVSD,A_MOVAPS,A_MOVUPD,A_MOVAPD,A_MOVUPS,
A_VMOVSS,A_VMOVSD,A_VMOVAPS,A_VMOVUPD,A_VMOVAPD,A_VMOVUPS],[]) and}
({(taicpu(hp1).ops=0) or }
({(MatchOpType(taicpu(hp1),top_reg,top_reg) or MatchOpType(taicpu(hp1),top_const,top_reg) or
(MatchOpType(taicpu(hp1),top_ref,top_reg))
) and }
not(RegInInstruction(NR_STACK_POINTER_REG,hp1)) { and not(RegInInstruction(NR_FRAME_POINTER_REG,hp1))}
)
) do
GetNextInstruction(hp1,hp1);
Result:=assigned(hp1);
end;
function SkipSimpleInstructions(var hp1 : tai) : Boolean;
begin
{ we can skip all instructions not messing with the stack pointer }
while assigned(hp1) and {MatchInstruction(taicpu(hp1),[A_LEA,A_MOV,A_MOVQ,A_MOVSQ,A_MOVSX,A_MOVSXD,A_MOVZX,
A_AND,A_OR,A_XOR,A_ADD,A_SHR,A_SHL,A_IMUL,A_SETcc,A_SAR,A_SUB,A_TEST,A_CMOVcc,
A_MOVSS,A_MOVSD,A_MOVAPS,A_MOVUPD,A_MOVAPD,A_MOVUPS,
A_VMOVSS,A_VMOVSD,A_VMOVAPS,A_VMOVUPD,A_VMOVAPD,A_VMOVUPS],[]) and}
({(taicpu(hp1).ops=0) or }
({(MatchOpType(taicpu(hp1),top_reg,top_reg) or MatchOpType(taicpu(hp1),top_const,top_reg) or
(MatchOpType(taicpu(hp1),top_ref,top_reg))
) and }
not(RegInInstruction(NR_STACK_POINTER_REG,hp1)) { and not(RegInInstruction(NR_FRAME_POINTER_REG,hp1))}
)
) do
GetNextInstruction(hp1,hp1);
Result:=assigned(hp1);
end;
function TX86AsmOptimizer.PostPeepholeOptLea(var p : tai) : Boolean;
var
hp1, hp2, hp3, hp4: tai;
@ -5821,6 +5825,58 @@ unit aoptx86;
end;
function TX86AsmOptimizer.PostPeepholeOptPush(var p : tai) : Boolean;
var
hp1, hp2, hp3, hp4: tai;
begin
Result:=false;
{ replace
push %rax
call procname
pop %rcx
ret
by
jmp procname
but do it only on level 4 because it destroys stack back traces
It depends on the fact, that the sequence push rax/pop rcx is used for stack alignment as rcx is volatile
for all supported calling conventions
}
if (cs_opt_level4 in current_settings.optimizerswitches) and
MatchOpType(taicpu(p),top_reg) and
(taicpu(p).oper[0]^.reg=NR_RAX) and
GetNextInstruction(p, hp1) and
{ Take a copy of hp1 }
SetAndTest(hp1, hp4) and
{ trick to skip label }
((hp1.typ=ait_instruction) or GetNextInstruction(hp1, hp1)) and
SkipSimpleInstructions(hp1) and
MatchInstruction(hp1,A_CALL,[S_NO]) and
GetNextInstruction(hp1, hp2) and
MatchInstruction(hp2,A_POP,[taicpu(p).opsize]) and
MatchOpType(taicpu(hp2),top_reg) and
(taicpu(hp2).oper[0]^.reg=NR_RCX) and
GetNextInstruction(hp2, hp3) and
{ trick to skip label }
((hp3.typ=ait_instruction) or GetNextInstruction(hp3, hp3)) and
MatchInstruction(hp3,A_RET,[S_NO]) and
(taicpu(hp3).ops=0) then
begin
taicpu(hp1).opcode := A_JMP;
taicpu(hp1).is_jmp := true;
DebugMsg(SPeepholeOptimization + 'PushCallPushRet2Jmp done',p);
RemoveCurrentP(p, hp4);
AsmL.Remove(hp2);
hp2.free;
AsmL.Remove(hp3);
hp3.free;
Result:=true;
end;
end;
function TX86AsmOptimizer.PostPeepholeOptMov(var p : tai) : Boolean;
var
Value, RegName: string;

2
compiler/x86_64/aoptcpu.pas
View File

@ -194,6 +194,8 @@ uses
Result:=PostPeepholeOptCall(p);
A_LEA:
Result:=PostPeepholeOptLea(p);
A_PUSH:
Result:=PostPeepholeOptPush(p);
else
;
end;

2
tests/test/tasm23b.pp
View File

@ -6,7 +6,7 @@ program tasm23b;
{$S-}
const
t_size = 33;
t_size = 25;
procedure t; assembler;
asm
mov eax, [rbx[5]][rdi][54][-17][45][4] { mov eax, [rbx+rdi+5Bh] }