gccrs: Migrate error state to optionals

gcc/rust/ChangeLog:

	* ast/rust-ast-builder.cc (Builder::self_ref_param): Remove error state
	and use optional.
	* ast/rust-ast-visitor.cc (DefaultASTVisitor::visit): Check label
	before visiting.
	* ast/rust-ast.cc (ContinueExpr::as_string): Retrieve label value.
	(Lifetime::as_string): Retrieve lifetime value.
	(ReferenceType::as_string): Likewise.
	(SelfParam::as_string): Likewise.
	* ast/rust-ast.h: Remove lifetime and LifetimeParam error state.
	* ast/rust-desugar-for-loops.cc (DesugarForLoops::DesugarCtx::make_break_arm):
	Use optional instead of error state.
	* ast/rust-expr.h (class ContinueExpr): Make label optional.
	* ast/rust-item.h (class SelfParam): Make lifetime optional.
	* ast/rust-type.h (class ReferenceType): Likewise.
	* backend/rust-compile-base.cc: Use optional for self param instead
	of error state.
	* backend/rust-compile-base.h: Update function prototype.
	* expand/rust-derive-clone.cc (DeriveClone::clone_fn): Use optional.
	* hir/rust-ast-lower-base.cc (ASTLoweringBase::lower_self): Lower
	lifetime only if it exists.
	* hir/rust-ast-lower-block.h: Lower loop label only if it exists.
	* hir/rust-ast-lower-expr.cc (ASTLoweringExpr::visit): Likewise.
	* hir/rust-ast-lower-implitem.cc (ASTLowerImplItem::visit): Remove
	references to error state.
	(ASTLowerTraitItem::visit): Lower self param only if it exists.
	* hir/rust-ast-lower-item.cc (ASTLoweringItem::visit): Use nullopt
	for default value instead of SelfParam error state.
	* hir/rust-ast-lower.cc (ASTLoweringExprWithBlock::visit): Lower label
	only if it exists.
	* hir/rust-hir-dump.cc (Dump::do_traitfunctiondecl): Print self only if
	it exists.
	(Dump::visit): Liewise.
	* hir/tree/rust-hir-bound.h: Remove error state.
	* hir/tree/rust-hir-expr.cc (ContinueExpr::ContinueExpr): Use optional
	in constructor for loop label.
	(BreakExpr::BreakExpr): Likewise.
	* hir/tree/rust-hir-expr.h (class ContinueExpr): Remove error state
	implementation.
	(class BreakExpr): Likewise.
	* hir/tree/rust-hir-generic-param.h: Likewise.
	* hir/tree/rust-hir-item.cc (SelfParam::SelfParam): Make lifetime
	optional.
	(Function::Function): Make self param optional.
	* hir/tree/rust-hir-item.h (class Function): Likewise.
	* hir/tree/rust-hir-type.cc (ReferenceType::ReferenceType): Make
	lifetime optional.
	* hir/tree/rust-hir-type.h (class ReferenceType): Likewise.
	* hir/tree/rust-hir.cc (ContinueExpr::as_string): Use new getter.
	(BreakExpr::as_string): Likewise.
	(Lifetime::as_string): Likewise.
	(ReferenceType::as_string): Likewise.
	(TraitFunctionDecl::as_string): Likewise.
	(SelfParam::as_string): Remove error state checking.
	* parse/rust-parse-impl.h (Parser::parse_generic_param): Adapt to
	optional.
	(Parser::parse_lifetime_params): Likewise.
	(Parser::parse_lifetime_params_objs): Likewise.
	(Parser::parse_lifetime_param): Likewise.
	(Parser::parse_lifetime_where_clause_item): Likewise.
	(Parser::parse_type_param_bound): Likewise.
	(Parser::parse_lifetime_bounds): Likewise.
	(Parser::parse_path_generic_args): Likewise.
	(Parser::parse_self_param): Likewise.
	(Parser::parse_break_expr): Likewise.
	(Parser::parse_continue_expr): Likewise.
	(Parser::parse_reference_type_inner): Likewise.
	* parse/rust-parse.h (class ParseLifetimeParamError): Add new class for
	lifetime param parsing errors.
	(class ParseLifetimeError): Add new class for lifetime parsing errors.
	(enum ParseSelfError): Add new class for self param parsing errors.
	* typecheck/rust-hir-type-check-implitem.cc (TypeCheckImplItem::visit):
	Use unchecked getter in checked context. And make anonymous region.
	* typecheck/rust-hir-type-check.cc (TraitItemReference::get_type_from_fn):
	Likewise.

Signed-off-by: Pierre-Emmanuel Patry <pierre-emmanuel.patry@embecosm.com>

1 files changed, 11 insertions, 11 deletions

diff --git a/gcc/rust/hir/tree/rust-hir-expr.h b/gcc/rust/hir/tree/rust-hir-expr.h
index 2d1059a..96f0cf6 100644
--- a/gcc/rust/hir/tree/rust-hir-expr.h
+++ b/gcc/rust/hir/tree/rust-hir-expr.h
@@ -45,9 +45,6 @@ public:
   LoopLabel (Analysis::NodeMapping mapping, Lifetime loop_label,
 	     location_t locus);
 
-  // Returns whether the LoopLabel is in an error state.
-  bool is_error () const { return label.is_error (); }
-
   location_t get_locus () const { return locus; }
 
   Analysis::NodeMapping &get_mappings () { return mappings; }
@@ -1806,25 +1803,27 @@ protected:
 // HIR node representing continue expression within loops
 class ContinueExpr : public ExprWithoutBlock
 {
-  Lifetime label;
+  tl::optional<Lifetime> label;
   location_t locus;
 
 public:
   std::string as_string () const override;
 
   // Returns true if the continue expr has a label.
-  bool has_label () const { return !label.is_error (); }
+  bool has_label () const { return label.has_value (); }
 
   // Constructor for a ContinueExpr with a label.
   ContinueExpr (Analysis::NodeMapping mappings, location_t locus,
-		Lifetime label, AST::AttrVec outer_attribs = AST::AttrVec ());
+		tl::optional<Lifetime> label,
+		AST::AttrVec outer_attribs = AST::AttrVec ());
 
   location_t get_locus () const override final { return locus; }
 
   void accept_vis (HIRFullVisitor &vis) override;
   void accept_vis (HIRExpressionVisitor &vis) override;
 
-  Lifetime &get_label () { return label; }
+  Lifetime &get_label () { return label.value (); }
+  const Lifetime &get_label () const { return label.value (); }
 
   ExprType get_expression_type () const final override
   {
@@ -1851,7 +1850,7 @@ protected:
 class BreakExpr : public ExprWithoutBlock
 {
   // bool has_label;
-  Lifetime label;
+  tl::optional<Lifetime> label;
 
   // bool has_break_expr;
   std::unique_ptr<Expr> break_expr;
@@ -1862,7 +1861,7 @@ public:
   std::string as_string () const override;
 
   // Returns whether the break expression has a label or not.
-  bool has_label () const { return !label.is_error (); }
+  bool has_label () const { return label.has_value (); }
 
   /* Returns whether the break expression has an expression used in the break or
    * not. */
@@ -1870,7 +1869,7 @@ public:
 
   // Constructor for a break expression
   BreakExpr (Analysis::NodeMapping mappings, location_t locus,
-	     Lifetime break_label,
+	     tl::optional<Lifetime> break_label,
 	     std::unique_ptr<Expr> expr_in_break = nullptr,
 	     AST::AttrVec outer_attribs = AST::AttrVec ());
 
@@ -1889,7 +1888,8 @@ public:
   void accept_vis (HIRFullVisitor &vis) override;
   void accept_vis (HIRExpressionVisitor &vis) override;
 
-  Lifetime &get_label () { return label; }
+  Lifetime &get_label () { return label.value (); }
+  const Lifetime &get_label () const { return label.value (); }
 
   Expr &get_expr () { return *break_expr; }