gccrs: refactor string methods in HIR

[lucasly-ba]

This patch changes as_string methods in HIR to to_string, we also create a to_debug_string method at the parent class of every HIR nodes.

gcc/rust/ChangeLog:

* backend/rust-compile-implitem.h: Change as_string to to_string.
* backend/rust-compile-type.cc (TyTyResolveCompile::visit): Likewise.
* checks/errors/rust-readonly-check.cc (ReadonlyChecker::check_variable): Likewise.
* hir/rust-hir-dump.cc (Dump::do_vis_item): Likewise.
(Dump::do_pathpattern): Likewise.
(Dump::do_typepathsegment): Likewise.
(Dump::do_baseloopexpr): Likewise.
(Dump::do_struct): Likewise.
(Dump::do_traitfunctiondecl): Likewise.
(Dump::do_externalitem): Likewise.
(Dump::do_tuplefield): Likewise.
(Dump::do_structfield): Likewise.
(Dump::visit): Likewise.
* hir/tree/rust-hir-bound-abstract.h: Likewise.
* hir/tree/rust-hir-bound.h: Likewise.
* hir/tree/rust-hir-expr-abstract.h: Likewise.
* hir/tree/rust-hir-expr.cc (OffsetOf::as_string): Likewise.
(OffsetOf::to_string): Likewise.
* hir/tree/rust-hir-expr.h: Likewise.
* hir/tree/rust-hir-generic-param.cc (ConstGenericParam::as_string): Likewise.
(ConstGenericParam::to_string): Likewise.
* hir/tree/rust-hir-generic-param.h: Likewise.
* hir/tree/rust-hir-item.h: Likewise.
* hir/tree/rust-hir-path.cc (PathInExpression::is_self): Likewise.
* hir/tree/rust-hir-path.h: Likewise.
* hir/tree/rust-hir-pattern-abstract.h: Likewise.
* hir/tree/rust-hir-pattern.h: Likewise.
* hir/tree/rust-hir-stmt.h: Likewise.
* hir/tree/rust-hir-trait-bound.h: Likewise.
* hir/tree/rust-hir-type-abstract.h: Likewise.
* hir/tree/rust-hir-type.h: Likewise.
* hir/tree/rust-hir-visibility.h: Likewise.
* hir/tree/rust-hir.cc (Crate::as_string): Likewise.
(Crate::to_string): Likewise.
(Visibility::as_string): Likewise.
(Visibility::to_string): Likewise.
(VisItem::as_string): Likewise.
(VisItem::to_string): Likewise.
(Item::as_string): Likewise.
(Item::to_string): Likewise.
(Module::as_string): Likewise.
(Module::to_string): Likewise.
(StaticItem::as_string): Likewise.
(StaticItem::to_string): Likewise.
(ExternCrate::as_string): Likewise.
(ExternCrate::to_string): Likewise.
(TupleStruct::as_string): Likewise.
(TupleStruct::to_string): Likewise.
(ConstantItem::as_string): Likewise.
(ConstantItem::to_string): Likewise.
(ImplBlock::as_string): Likewise.
(ImplBlock::to_string): Likewise.
(StructStruct::as_string): Likewise.
(StructStruct::to_string): Likewise.
(UseDeclaration::as_string): Likewise.
(UseDeclaration::to_string): Likewise.
(UseTreeGlob::as_string): Likewise.
(UseTreeGlob::to_string): Likewise.
(UseTreeList::as_string): Likewise.
(UseTreeList::to_string): Likewise.
(UseTreeRebind::as_string): Likewise.
(UseTreeRebind::to_string): Likewise.
(Enum::as_string): Likewise.
(Enum::to_string): Likewise.
(Trait::as_string): Likewise.
(Trait::to_string): Likewise.
(Union::as_string): Likewise.
(Union::to_string): Likewise.
(Function::as_string): Likewise.
(Function::to_string): Likewise.
(WhereClause::as_string): Likewise.
(WhereClause::to_string): Likewise.
(BlockExpr::as_string): Likewise.
(BlockExpr::to_string): Likewise.
(AnonConst::as_string): Likewise.
(AnonConst::to_string): Likewise.
(ConstBlock::as_string): Likewise.
(ConstBlock::to_string): Likewise.
(TypeAlias::as_string): Likewise.
(TypeAlias::to_string): Likewise.
(ExternBlock::as_string): Likewise.
(ExternBlock::to_string): Likewise.
(PathInExpression::as_string): Likewise.
(PathInExpression::to_string): Likewise.
(ExprStmt::as_string): Likewise.
(ExprStmt::to_string): Likewise.
(ClosureParam::as_string): Likewise.
(ClosureParam::to_string): Likewise.
(ClosureExpr::as_string): Likewise.
(ClosureExpr::to_string): Likewise.
(PathPattern::as_string): Likewise.
(PathPattern::to_string): Likewise.
(QualifiedPathType::as_string): Likewise.
(QualifiedPathType::to_string): Likewise.
(QualifiedPathInExpression::as_string): Likewise.
(QualifiedPathInExpression::to_string): Likewise.
(BorrowExpr::as_string): Likewise.
(BorrowExpr::to_string): Likewise.
(ReturnExpr::as_string): Likewise.
(ReturnExpr::to_string): Likewise.
(GroupedExpr::as_string): Likewise.
(GroupedExpr::to_string): Likewise.
(RangeToExpr::as_string): Likewise.
(RangeToExpr::to_string): Likewise.
(ContinueExpr::as_string): Likewise.
(ContinueExpr::to_string): Likewise.
(NegationExpr::as_string): Likewise.
(NegationExpr::to_string): Likewise.
(RangeFromExpr::as_string): Likewise.
(RangeFromExpr::to_string): Likewise.
(RangeFullExpr::as_string): Likewise.
(RangeFullExpr::to_string): Likewise.
(ArrayIndexExpr::as_string): Likewise.
(ArrayIndexExpr::to_string): Likewise.
(AssignmentExpr::as_string): Likewise.
(AssignmentExpr::to_string): Likewise.
(CompoundAssignmentExpr::as_string): Likewise.
(CompoundAssignmentExpr::to_string): Likewise.
(AsyncBlockExpr::as_string): Likewise.
(AsyncBlockExpr::to_string): Likewise.
(ComparisonExpr::as_string): Likewise.
(ComparisonExpr::to_string): Likewise.
(MethodCallExpr::as_string): Likewise.
(MethodCallExpr::to_string): Likewise.
(TupleIndexExpr::as_string): Likewise.
(TupleIndexExpr::to_string): Likewise.
(DereferenceExpr::as_string): Likewise.
(DereferenceExpr::to_string): Likewise.
(FieldAccessExpr::as_string): Likewise.
(FieldAccessExpr::to_string): Likewise.
(LazyBooleanExpr::as_string): Likewise.
(LazyBooleanExpr::to_string): Likewise.
(RangeFromToExpr::as_string): Likewise.
(RangeFromToExpr::to_string): Likewise.
(RangeToInclExpr::as_string): Likewise.
(RangeToInclExpr::to_string): Likewise.
(UnsafeBlockExpr::as_string): Likewise.
(UnsafeBlockExpr::to_string): Likewise.
(IfExpr::as_string): Likewise.
(IfExpr::to_string): Likewise.
(IfExprConseqElse::as_string): Likewise.
(IfExprConseqElse::to_string): Likewise.
(RangeFromToInclExpr::as_string): Likewise.
(RangeFromToInclExpr::to_string): Likewise.
(ErrorPropagationExpr::as_string): Likewise.
(ErrorPropagationExpr::to_string): Likewise.
(ArithmeticOrLogicalExpr::as_string): Likewise.
(ArithmeticOrLogicalExpr::to_string): Likewise.
(CallExpr::as_string): Likewise.
(CallExpr::to_string): Likewise.
(WhileLoopExpr::as_string): Likewise.
(WhileLoopExpr::to_string): Likewise.
(WhileLetLoopExpr::as_string): Likewise.
(WhileLetLoopExpr::to_string): Likewise.
(LoopExpr::as_string): Likewise.
(LoopExpr::to_string): Likewise.
(ArrayExpr::as_string): Likewise.
(ArrayExpr::to_string): Likewise.
(AwaitExpr::as_string): Likewise.
(AwaitExpr::to_string): Likewise.
(BreakExpr::as_string): Likewise.
(BreakExpr::to_string): Likewise.
(LoopLabel::as_string): Likewise.
(LoopLabel::to_string): Likewise.
(MatchArm::as_string): Likewise.
(MatchArm::to_string): Likewise.
(MatchCase::as_string): Likewise.
(MatchCase::to_string): Likewise.
(MatchCaseBlockExpr::as_string): Likewise.
(MatchCaseBlockExpr::to_string): Likewise.
(MatchCaseExpr::as_string): Likewise.
(MatchCaseExpr::to_string): Likewise.
(MatchExpr::as_string): Likewise.
(MatchExpr::to_string): Likewise.
(TupleExpr::as_string): Likewise.
(TupleExpr::to_string): Likewise.
(FunctionParam::as_string): Likewise.
(FunctionParam::to_string): Likewise.
(FunctionQualifiers::as_string): Likewise.
(FunctionQualifiers::to_string): Likewise.
(TraitBound::as_string): Likewise.
(TraitBound::to_string): Likewise.
(LifetimeParam::as_string): Likewise.
(LifetimeParam::to_string): Likewise.
(QualifiedPathInType::as_string): Likewise.
(QualifiedPathInType::to_string): Likewise.
(Lifetime::as_string): Likewise.
(Lifetime::to_string): Likewise.
(TypePath::as_string): Likewise.
(TypePath::to_string): Likewise.
(TypeParam::as_string): Likewise.
(TypeParam::to_string): Likewise.
(PathPattern::convert_to_simple_path): Likewise.
(TypePath::as_simple_path): Likewise.
(PathExprSegment::as_string): Likewise.
(PathExprSegment::to_string): Likewise.
(GenericArgs::as_string): Likewise.
(GenericArgs::to_string): Likewise.
(GenericArgsBinding::as_string): Likewise.
(GenericArgsBinding::to_string): Likewise.
(RangePattern::as_string): Likewise.
(RangePattern::to_string): Likewise.
(RangePatternBoundLiteral::as_string): Likewise.
(RangePatternBoundLiteral::to_string): Likewise.
(SlicePatternItemsNoRest::as_string): Likewise.
(SlicePatternItemsNoRest::to_string): Likewise.
(SlicePatternItemsHasRest::as_string): Likewise.
(SlicePatternItemsHasRest::to_string): Likewise.
(SlicePattern::as_string): Likewise.
(SlicePattern::to_string): Likewise.
(AltPattern::as_string): Likewise.
(AltPattern::to_string): Likewise.
(TuplePatternItemsNoRest::as_string): Likewise.
(TuplePatternItemsNoRest::to_string): Likewise.
(TuplePatternItemsHasRest::as_string): Likewise.
(TuplePatternItemsHasRest::to_string): Likewise.
(TuplePattern::as_string): Likewise.
(TuplePattern::to_string): Likewise.
(StructPatternField::as_string): Likewise.
(StructPatternField::to_string): Likewise.
(StructPatternFieldIdent::as_string): Likewise.
(StructPatternFieldIdent::to_string): Likewise.
(StructPatternFieldTuplePat::as_string): Likewise.
(StructPatternFieldTuplePat::to_string): Likewise.
(StructPatternFieldIdentPat::as_string): Likewise.
(StructPatternFieldIdentPat::to_string): Likewise.
(StructPatternElements::as_string): Likewise.
(StructPatternElements::to_string): Likewise.
(StructPattern::as_string): Likewise.
(StructPattern::to_string): Likewise.
(LiteralPattern::as_string): Likewise.
(LiteralPattern::to_string): Likewise.
(ReferencePattern::as_string): Likewise.
(ReferencePattern::to_string): Likewise.
(IdentifierPattern::as_string): Likewise.
(IdentifierPattern::to_string): Likewise.
(TupleStructItemsNoRest::as_string): Likewise.
(TupleStructItemsNoRest::to_string): Likewise.
(TupleStructItemsHasRest::as_string): Likewise.
(TupleStructItemsHasRest::to_string): Likewise.
(TupleStructPattern::as_string): Likewise.
(TupleStructPattern::to_string): Likewise.
(LetStmt::as_string): Likewise.
(LetStmt::to_string): Likewise.
(Expr::as_string): Likewise.
(Expr::to_string): Likewise.
(InferredType::as_string): Likewise.
(InferredType::to_string): Likewise.
(TypeCastExpr::as_string): Likewise.
(TypeCastExpr::to_string): Likewise.
(ImplTraitType::as_string): Likewise.
(ImplTraitType::to_string): Likewise.
(ReferenceType::as_string): Likewise.
(ReferenceType::to_string): Likewise.
(RawPointerType::as_string): Likewise.
(RawPointerType::to_string): Likewise.
(TraitObjectType::as_string): Likewise.
(TraitObjectType::to_string): Likewise.
(BareFunctionType::as_string): Likewise.
(BareFunctionType::to_string): Likewise.
(TypePathSegmentGeneric::as_string): Likewise.
(TypePathSegmentGeneric::to_string): Likewise.
(TypePathFunction::as_string): Likewise.
(TypePathFunction::to_string): Likewise.
(TypePathSegmentFunction::as_string): Likewise.
(TypePathSegmentFunction::to_string): Likewise.
(ArrayType::as_string): Likewise.
(ArrayType::to_string): Likewise.
(SliceType::as_string): Likewise.
(SliceType::to_string): Likewise.
(TupleType::as_string): Likewise.
(TupleType::to_string): Likewise.
(StructExpr::as_string): Likewise.
(StructExpr::to_string): Likewise.
(StructExprStruct::as_string): Likewise.
(StructExprStruct::to_string): Likewise.
(StructBase::as_string): Likewise.
(StructBase::to_string): Likewise.
(StructExprFieldWithVal::as_string): Likewise.
(StructExprFieldWithVal::to_string): Likewise.
(StructExprFieldIdentifierValue::as_string): Likewise.
(StructExprFieldIdentifierValue::to_string): Likewise.
(StructExprFieldIndexValue::as_string): Likewise.
(StructExprFieldIndexValue::to_string): Likewise.
(StructExprStructFields::as_string): Likewise.
(StructExprStructFields::to_string): Likewise.
(EnumItem::as_string): Likewise.
(EnumItem::to_string): Likewise.
(EnumItemTuple::as_string): Likewise.
(EnumItemTuple::to_string): Likewise.
(TupleField::as_string): Likewise.
(TupleField::to_string): Likewise.
(EnumItemStruct::as_string): Likewise.
(EnumItemStruct::to_string): Likewise.
(StructField::as_string): Likewise.
(StructField::to_string): Likewise.
(EnumItemDiscriminant::as_string): Likewise.
(EnumItemDiscriminant::to_string): Likewise.
(ExternalItem::as_string): Likewise.
(ExternalItem::to_string): Likewise.
(ExternalStaticItem::as_string): Likewise.
(ExternalStaticItem::to_string): Likewise.
(ExternalFunctionItem::as_string): Likewise.
(ExternalFunctionItem::to_string): Likewise.
(ExternalTypeItem::as_string): Likewise.
(ExternalTypeItem::to_string): Likewise.
(NamedFunctionParam::as_string): Likewise.
(NamedFunctionParam::to_string): Likewise.
(attr.as_string): Likewise.
(attr.to_string): Likewise.
(TraitItemFunc::as_string): Likewise.
(TraitItemFunc::to_string): Likewise.
(TraitFunctionDecl::as_string): Likewise.
(TraitFunctionDecl::to_string): Likewise.
(TraitItemConst::as_string): Likewise.
(TraitItemConst::to_string): Likewise.
(TraitItemType::as_string): Likewise.
(TraitItemType::to_string): Likewise.
(SelfParam::as_string): Likewise.
(SelfParam::to_string): Likewise.
(ArrayElemsCopied::as_string): Likewise.
(ArrayElemsCopied::to_string): Likewise.
(LifetimeWhereClauseItem::as_string): Likewise.
(LifetimeWhereClauseItem::to_string): Likewise.
(TypeBoundWhereClauseItem::as_string): Likewise.
(TypeBoundWhereClauseItem::to_string): Likewise.
(ArrayElemsValues::as_string): Likewise.
(ArrayElemsValues::to_string): Likewise.
(MaybeNamedParam::as_string): Likewise.
(MaybeNamedParam::to_string): Likewise.
* hir/tree/rust-hir.h: Likewise.
* rust-session-manager.cc (Session::dump_hir): Likewise.
* typecheck/rust-hir-dot-operator.cc (MethodResolver::select): Likewise.
* typecheck/rust-hir-path-probe.cc (PathProbeType::visit): Likewise.
(PathProbeType::process_enum_item_for_candiates): Likewise.
* typecheck/rust-hir-path-probe.h: Likewise.
* typecheck/rust-hir-type-check-expr.cc (emit_ambiguous_resolution_error): Likewise.
(TypeCheckExpr::visit): Likewise.
(TypeCheckExpr::resolve_fn_trait_call): Likewise.
* typecheck/rust-hir-type-check-path.cc (TypeCheckExpr::visit): Likewise.
(TypeCheckExpr::resolve_root_path): Likewise.
* typecheck/rust-hir-type-check-pattern.cc (TypeCheckPattern::visit): Likewise.
* typecheck/rust-hir-type-check-type.cc (TypeCheckType::visit): Likewise.
(TypeCheckType::resolve_root_path): Likewise.
(ResolveWhereClauseItem::visit): Likewise.
* typecheck/rust-tyty-bounds.cc: Likewise.
* typecheck/rust-tyty.cc (VariantDef::as_string): Likewise.
(FnType::as_string): Likewise.

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