Faster MutatingScope->getNodeKey()

[staabm]

saves 0,3-0,4 seconds on php bin/phpstan analyse src/Analyser/ src/Rules/ -v --debug.
also reduces memory consumption by a few megabytes (because not every variable needs to hold a expr-printed attribute).

getNodeKey is invoked by-far most often with Variable, see numer of invocations per node-type:

array(67) {
  ["PHPStan\Node\Expr\IntertwinedVariableByReferenceWithExpr"]=>
  int(4)
  ["PhpParser\Node\Expr\BinaryOp\LogicalXor"]=>
  int(5)
  ["PhpParser\Node\Expr\PostDec"]=>
  int(8)
  ["PhpParser\Node\Expr\AssignOp\Minus"]=>
  int(8)
  ["PHPStan\Node\IssetExpr"]=>
  int(12)
  ["PhpParser\Node\Expr\Throw_"]=>
  int(18)
  ["PhpParser\Node\Expr\ErrorSuppress"]=>
  int(25)
  ["PhpParser\Node\Expr\BinaryOp\Mod"]=>
  int(34)
  ["PhpParser\Node\Expr\BitwiseNot"]=>
  int(35)
  ["PhpParser\Node\Expr\BinaryOp\BitwiseOr"]=>
  int(38)
  ["PhpParser\Node\Expr\BinaryOp\Mul"]=>
  int(41)
  ["PhpParser\Node\Expr\BinaryOp\Spaceship"]=>
  int(46)
  ["PhpParser\Node\Expr\PreDec"]=>
  int(46)
  ["PhpParser\Node\Expr\Cast\Int_"]=>
  int(56)
  ["PhpParser\Node\Expr\Clone_"]=>
  int(60)
  ["PhpParser\Node\Expr\Cast\Bool_"]=>
  int(64)
  ["PhpParser\Node\Expr\AssignOp\BitwiseOr"]=>
  int(79)
  ["PhpParser\Node\Expr\AssignOp\Plus"]=>
  int(85)
  ["PhpParser\Node\Expr\List_"]=>
  int(98)
  ["PhpParser\Node\Expr\BinaryOp\SmallerOrEqual"]=>
  int(115)
  ["PhpParser\Node\Expr\BinaryOp\Equal"]=>
  int(121)
  ["PhpParser\Node\Expr\AssignOp\Concat"]=>
  int(148)
  ["PhpParser\Node\Expr\StaticPropertyFetch"]=>
  int(163)
  ["PhpParser\Node\Expr\PostInc"]=>
  int(230)
  ["PhpParser\Node\Expr\Include_"]=>
  int(235)
  ["PhpParser\Node\Expr\AssignOp\Coalesce"]=>
  int(275)
  ["PhpParser\Node\Expr\UnaryMinus"]=>
  int(311)
  ["PhpParser\Node\Expr\Closure"]=>
  int(408)
  ["PhpParser\Node\Expr\BinaryOp\BitwiseAnd"]=>
  int(436)
  ["PhpParser\Node\Expr\BinaryOp\GreaterOrEqual"]=>
  int(478)
  ["PhpParser\Node\Expr\PreInc"]=>
  int(784)
  ["PhpParser\Node\Expr\BinaryOp\Smaller"]=>
  int(793)
  ["PhpParser\Node\Expr\BinaryOp\Minus"]=>
  int(1031)
  ["PHPStan\Node\Expr\AlwaysRememberedExpr"]=>
  int(1161)
  ["PhpParser\Node\Expr\BinaryOp\Plus"]=>
  int(1199)
  ["PhpParser\Node\Expr\ArrowFunction"]=>
  int(1211)
  ["PhpParser\Node\Expr\Cast\String_"]=>
  int(1710)
  ["PhpParser\Node\Expr\BinaryOp\Greater"]=>
  int(1941)
  ["PhpParser\Node\Scalar\Float_"]=>
  int(2085)
  ["PHPStan\Node\Expr\OriginalForeachKeyExpr"]=>
  int(2157)
  ["PhpParser\Node\Expr\BinaryOp\Concat"]=>
  int(2303)
  ["PHPStan\Node\Expr\TypeExpr"]=>
  int(2689)
  ["PhpParser\Node\Expr\BinaryOp\Coalesce"]=>
  int(3159)
  ["PhpParser\Node\Expr\Ternary"]=>
  int(3611)
  ["PHPStan\Node\Expr\ParameterVariableOriginalValueExpr"]=>
  int(3730)
  ["PhpParser\Node\Expr\Isset_"]=>
  int(3837)
  ["PHPStan\Node\Expr\PropertyInitializationExpr"]=>
  int(4632)
  ["PhpParser\Node\Expr\BinaryOp\BooleanOr"]=>
  int(9840)
  ["PHPStan\Node\Expr\ForeachValueByRefExpr"]=>
  int(10580)
  ["PhpParser\Node\Expr\BinaryOp\NotIdentical"]=>
  int(11218)
  ["PhpParser\Node\Expr\New_"]=>
  int(12485)
  ["PhpParser\Node\Expr\BinaryOp\BooleanAnd"]=>
  int(23353)
  ["PhpParser\Node\Scalar\Int_"]=>
  int(24669)
  ["PhpParser\Node\Expr\BooleanNot"]=>
  int(24972)
  ["PhpParser\Node\Expr\Instanceof_"]=>
  int(25872)
  ["PhpParser\Node\Expr\Array_"]=>
  int(29885)
  ["PhpParser\Node\Expr\ClassConstFetch"]=>
  int(29916)
  ["PhpParser\Node\Expr\Assign"]=>
  int(33054)
  ["PhpParser\Node\Expr\BinaryOp\Identical"]=>
  int(46624)
  ["PhpParser\Node\Scalar\String_"]=>
  int(62483)
  ["PhpParser\Node\Expr\StaticCall"]=>
  int(67364)
  ["PhpParser\Node\Expr\FuncCall"]=>
  int(68771)
  ["PhpParser\Node\Expr\ArrayDimFetch"]=>
  int(76027)
  ["PhpParser\Node\Expr\ConstFetch"]=>
  int(76787)
  ["PhpParser\Node\Expr\PropertyFetch"]=>
  int(170030)
  ["PhpParser\Node\Expr\MethodCall"]=>
  int(475115)
  ["PhpParser\Node\Expr\Variable"]=>
  int(1037687)
}

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[phpstan-bot]

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