Remove lambda iterators in various HIR classes

This patch removes the lambda iterators used in various HIR objects.
These iterators make interacting with the IR for static analysis more
difficult. Instead, get_X () helpers are added for accessing elements,
and uses of the iterators replaced with for loops.

The following objects are adjusted in this patch:
- HIR::ArrayElemsValues
- HIR::TupleExpr
- HIR::StructExprField
- HIR::StructStruct
- HIR::TupleStruct

Fixes: #703, #704, #705, #706, #707

10 files changed, 107 insertions, 148 deletions

diff --git a/gcc/rust/backend/rust-compile-expr.h b/gcc/rust/backend/rust-compile-expr.h
index eb245dc..7c40466 100644
--- a/gcc/rust/backend/rust-compile-expr.h
+++ b/gcc/rust/backend/rust-compile-expr.h
@@ -412,11 +412,11 @@ public:
 
   void visit (HIR::ArrayElemsValues &elems) override
   {
-    elems.iterate ([&] (HIR::Expr *e) mutable -> bool {
-      Bexpression *translated_expr = CompileExpr::Compile (e, ctx);
-      constructor.push_back (translated_expr);
-      return true;
-    });
+    for (auto &elem : elems.get_values ())
+      {
+	Bexpression *translated_expr = CompileExpr::Compile (elem.get (), ctx);
+	constructor.push_back (translated_expr);
+      }
   }
 
   void visit (HIR::ArrayElemsCopied &elems) override
@@ -646,11 +646,11 @@ public:
     // this assumes all fields are in order from type resolution and if a base
     // struct was specified those fields are filed via accesors
     std::vector<Bexpression *> vals;
-    struct_expr.iterate ([&] (HIR::StructExprField *field) mutable -> bool {
-      Bexpression *expr = CompileStructExprField::Compile (field, ctx);
-      vals.push_back (expr);
-      return true;
-    });
+    for (auto &field : struct_expr.get_fields ())
+      {
+	Bexpression *expr = CompileStructExprField::Compile (field.get (), ctx);
+	vals.push_back (expr);
+      }
 
     translated
       = ctx->get_backend ()->constructor_expression (type, vals,
diff --git a/gcc/rust/hir/tree/rust-hir-expr.h b/gcc/rust/hir/tree/rust-hir-expr.h
index 05bc1f9..3fb6c87 100644
--- a/gcc/rust/hir/tree/rust-hir-expr.h
+++ b/gcc/rust/hir/tree/rust-hir-expr.h
@@ -796,14 +796,7 @@ public:
 
   size_t get_num_elements () const { return values.size (); }
 
-  void iterate (std::function<bool (Expr *)> cb)
-  {
-    for (auto it = values.begin (); it != values.end (); it++)
-      {
-	if (!cb ((*it).get ()))
-	  return;
-      }
-  }
+  std::vector<std::unique_ptr<Expr> > &get_values () { return values; }
 
 protected:
   ArrayElemsValues *clone_array_elems_impl () const override
@@ -1070,15 +1063,6 @@ public:
 
   bool is_unit () const { return tuple_elems.size () == 0; }
 
-  void iterate (std::function<bool (Expr *)> cb)
-  {
-    for (auto &tuple_elem : tuple_elems)
-      {
-	if (!cb (tuple_elem.get ()))
-	  return;
-      }
-  }
-
 protected:
   /* Use covariance to implement clone function as returning this object rather
    * than base */
@@ -1491,15 +1475,6 @@ public:
 
   void accept_vis (HIRVisitor &vis) override;
 
-  void iterate (std::function<bool (StructExprField *)> cb)
-  {
-    for (auto &field : fields)
-      {
-	if (!cb (field.get ()))
-	  return;
-      }
-  }
-
   std::vector<std::unique_ptr<StructExprField> > &get_fields ()
   {
     return fields;
@@ -1510,11 +1485,6 @@ public:
     return fields;
   };
 
-  std::vector<std::unique_ptr<StructExprField> > get_fields_as_owner ()
-  {
-    return std::move (fields);
-  };
-
   void set_fields_as_owner (
     std::vector<std::unique_ptr<StructExprField> > new_fields)
   {
diff --git a/gcc/rust/hir/tree/rust-hir-item.h b/gcc/rust/hir/tree/rust-hir-item.h
index 8cd7a01..54e32f7 100644
--- a/gcc/rust/hir/tree/rust-hir-item.h
+++ b/gcc/rust/hir/tree/rust-hir-item.h
@@ -1492,14 +1492,7 @@ public:
 
   void accept_vis (HIRVisitor &vis) override;
 
-  void iterate (std::function<bool (StructField &)> cb)
-  {
-    for (auto &field : fields)
-      {
-	if (!cb (field))
-	  return;
-      }
-  }
+  std::vector<StructField> &get_fields () { return fields; }
 
 protected:
   /* Use covariance to implement clone function as returning this object
@@ -1610,15 +1603,6 @@ public:
   std::vector<TupleField> &get_fields () { return fields; }
   const std::vector<TupleField> &get_fields () const { return fields; }
 
-  void iterate (std::function<bool (TupleField &)> cb)
-  {
-    for (auto &field : fields)
-      {
-	if (!cb (field))
-	  return;
-      }
-  }
-
 protected:
   /* Use covariance to implement clone function as returning this object
    * rather than base */
diff --git a/gcc/rust/lint/rust-lint-marklive.h b/gcc/rust/lint/rust-lint-marklive.h
index 062bb96..cd72ef0 100644
--- a/gcc/rust/lint/rust-lint-marklive.h
+++ b/gcc/rust/lint/rust-lint-marklive.h
@@ -81,18 +81,18 @@ public:
 
   void visit (HIR::ArrayElemsValues &expr) override
   {
-    expr.iterate ([&] (HIR::Expr *expr) mutable -> bool {
-      expr->accept_vis (*this);
-      return true;
-    });
+    for (auto &elem : expr.get_values ())
+      {
+	elem->accept_vis (*this);
+      }
   }
 
   void visit (HIR::TupleExpr &expr) override
   {
-    expr.iterate ([&] (HIR::Expr *expr) mutable -> bool {
-      expr->accept_vis (*this);
-      return true;
-    });
+    for (auto &elem : expr.get_tuple_elems ())
+      {
+	elem->accept_vis (*this);
+      }
   }
 
   void visit (HIR::BlockExpr &expr) override
@@ -236,10 +236,10 @@ public:
 
   void visit (HIR::StructExprStructFields &stct) override
   {
-    stct.iterate ([&] (HIR::StructExprField *field) -> bool {
-      field->accept_vis (*this);
-      return true;
-    });
+    for (auto &field : stct.get_fields ())
+      {
+	field->accept_vis (*this);
+      }
 
     stct.get_struct_name ().accept_vis (*this);
     if (stct.has_struct_base ())
diff --git a/gcc/rust/lint/rust-lint-scan-deadcode.h b/gcc/rust/lint/rust-lint-scan-deadcode.h
index 464852a..152858a 100644
--- a/gcc/rust/lint/rust-lint-scan-deadcode.h
+++ b/gcc/rust/lint/rust-lint-scan-deadcode.h
@@ -88,16 +88,16 @@ public:
     else
       {
 	// only warn the unused fields when in unwarned struct.
-	stct.iterate ([&] (HIR::StructField &field) -> bool {
-	  HirId field_hir_id = field.get_mappings ().get_hirid ();
-	  if (should_warn (field_hir_id))
-	    {
-	      rust_warning_at (field.get_locus (), 0,
-			       "field is never read: %<%s%>",
-			       field.get_field_name ().c_str ());
-	    }
-	  return true;
-	});
+	for (auto &field : stct.get_fields ())
+	  {
+	    HirId field_hir_id = field.get_mappings ().get_hirid ();
+	    if (should_warn (field_hir_id))
+	      {
+		rust_warning_at (field.get_locus (), 0,
+				 "field is never read: %<%s%>",
+				 field.get_field_name ().c_str ());
+	      }
+	  }
       }
   }
 
diff --git a/gcc/rust/typecheck/rust-hir-type-check-expr.h b/gcc/rust/typecheck/rust-hir-type-check-expr.h
index 28b9851..d9eeb4e 100644
--- a/gcc/rust/typecheck/rust-hir-type-check-expr.h
+++ b/gcc/rust/typecheck/rust-hir-type-check-expr.h
@@ -880,10 +880,11 @@ public:
   void visit (HIR::ArrayElemsValues &elems) override
   {
     std::vector<TyTy::BaseType *> types;
-    elems.iterate ([&] (HIR::Expr *e) mutable -> bool {
-      types.push_back (TypeCheckExpr::Resolve (e, false));
-      return true;
-    });
+
+    for (auto &elem : elems.get_values ())
+      {
+	types.push_back (TypeCheckExpr::Resolve (elem.get (), false));
+      }
 
     infered_array_elems
       = TyTy::TyVar::get_implicit_infer_var (root_array_expr_locus).get_tyty ();
diff --git a/gcc/rust/typecheck/rust-hir-type-check-stmt.h b/gcc/rust/typecheck/rust-hir-type-check-stmt.h
index 5f4721b..3f8d17e 100644
--- a/gcc/rust/typecheck/rust-hir-type-check-stmt.h
+++ b/gcc/rust/typecheck/rust-hir-type-check-stmt.h
@@ -144,17 +144,18 @@ public:
     std::vector<TyTy::StructFieldType *> fields;
 
     size_t idx = 0;
-    struct_decl.iterate ([&] (HIR::TupleField &field) mutable -> bool {
-      TyTy::BaseType *field_type
-	= TypeCheckType::Resolve (field.get_field_type ().get ());
-      TyTy::StructFieldType *ty_field
-	= new TyTy::StructFieldType (field.get_mappings ().get_hirid (),
-				     std::to_string (idx), field_type);
-      fields.push_back (ty_field);
-      context->insert_type (field.get_mappings (), ty_field->get_field_type ());
-      idx++;
-      return true;
-    });
+    for (auto &field : struct_decl.get_fields ())
+      {
+	TyTy::BaseType *field_type
+	  = TypeCheckType::Resolve (field.get_field_type ().get ());
+	TyTy::StructFieldType *ty_field
+	  = new TyTy::StructFieldType (field.get_mappings ().get_hirid (),
+				       std::to_string (idx), field_type);
+	fields.push_back (ty_field);
+	context->insert_type (field.get_mappings (),
+			      ty_field->get_field_type ());
+	idx++;
+      }
 
     TyTy::BaseType *type
       = new TyTy::ADTType (struct_decl.get_mappings ().get_hirid (),
@@ -196,16 +197,17 @@ public:
       }
 
     std::vector<TyTy::StructFieldType *> fields;
-    struct_decl.iterate ([&] (HIR::StructField &field) mutable -> bool {
-      TyTy::BaseType *field_type
-	= TypeCheckType::Resolve (field.get_field_type ().get ());
-      TyTy::StructFieldType *ty_field
-	= new TyTy::StructFieldType (field.get_mappings ().get_hirid (),
-				     field.get_field_name (), field_type);
-      fields.push_back (ty_field);
-      context->insert_type (field.get_mappings (), ty_field->get_field_type ());
-      return true;
-    });
+    for (auto &field : struct_decl.get_fields ())
+      {
+	TyTy::BaseType *field_type
+	  = TypeCheckType::Resolve (field.get_field_type ().get ());
+	TyTy::StructFieldType *ty_field
+	  = new TyTy::StructFieldType (field.get_mappings ().get_hirid (),
+				       field.get_field_name (), field_type);
+	fields.push_back (ty_field);
+	context->insert_type (field.get_mappings (),
+			      ty_field->get_field_type ());
+      }
 
     TyTy::BaseType *type
       = new TyTy::ADTType (struct_decl.get_mappings ().get_hirid (),
diff --git a/gcc/rust/typecheck/rust-hir-type-check-toplevel.h b/gcc/rust/typecheck/rust-hir-type-check-toplevel.h
index 9fac813..131149f 100644
--- a/gcc/rust/typecheck/rust-hir-type-check-toplevel.h
+++ b/gcc/rust/typecheck/rust-hir-type-check-toplevel.h
@@ -79,17 +79,18 @@ public:
     std::vector<TyTy::StructFieldType *> fields;
 
     size_t idx = 0;
-    struct_decl.iterate ([&] (HIR::TupleField &field) mutable -> bool {
-      TyTy::BaseType *field_type
-	= TypeCheckType::Resolve (field.get_field_type ().get ());
-      TyTy::StructFieldType *ty_field
-	= new TyTy::StructFieldType (field.get_mappings ().get_hirid (),
-				     std::to_string (idx), field_type);
-      fields.push_back (ty_field);
-      context->insert_type (field.get_mappings (), ty_field->get_field_type ());
-      idx++;
-      return true;
-    });
+    for (auto &field : struct_decl.get_fields ())
+      {
+	TyTy::BaseType *field_type
+	  = TypeCheckType::Resolve (field.get_field_type ().get ());
+	TyTy::StructFieldType *ty_field
+	  = new TyTy::StructFieldType (field.get_mappings ().get_hirid (),
+				       std::to_string (idx), field_type);
+	fields.push_back (ty_field);
+	context->insert_type (field.get_mappings (),
+			      ty_field->get_field_type ());
+	idx++;
+      }
 
     TyTy::BaseType *type
       = new TyTy::ADTType (struct_decl.get_mappings ().get_hirid (),
@@ -136,16 +137,18 @@ public:
       }
 
     std::vector<TyTy::StructFieldType *> fields;
-    struct_decl.iterate ([&] (HIR::StructField &field) mutable -> bool {
-      TyTy::BaseType *field_type
-	= TypeCheckType::Resolve (field.get_field_type ().get ());
-      TyTy::StructFieldType *ty_field
-	= new TyTy::StructFieldType (field.get_mappings ().get_hirid (),
-				     field.get_field_name (), field_type);
-      fields.push_back (ty_field);
-      context->insert_type (field.get_mappings (), ty_field->get_field_type ());
-      return true;
-    });
+
+    for (auto &field : struct_decl.get_fields ())
+      {
+	TyTy::BaseType *field_type
+	  = TypeCheckType::Resolve (field.get_field_type ().get ());
+	TyTy::StructFieldType *ty_field
+	  = new TyTy::StructFieldType (field.get_mappings ().get_hirid (),
+				       field.get_field_name (), field_type);
+	fields.push_back (ty_field);
+	context->insert_type (field.get_mappings (),
+			      ty_field->get_field_type ());
+      }
 
     TyTy::BaseType *type
       = new TyTy::ADTType (struct_decl.get_mappings ().get_hirid (),
diff --git a/gcc/rust/typecheck/rust-hir-type-check.cc b/gcc/rust/typecheck/rust-hir-type-check.cc
index 0cd6883..a30f4c4 100644
--- a/gcc/rust/typecheck/rust-hir-type-check.cc
+++ b/gcc/rust/typecheck/rust-hir-type-check.cc
@@ -153,20 +153,21 @@ TypeCheckStructExpr::visit (HIR::StructExprStructFields &struct_expr)
 
   std::vector<TyTy::StructFieldType *> infered_fields;
   bool ok = true;
-  struct_expr.iterate ([&] (HIR::StructExprField *field) mutable -> bool {
-    resolved_field_value_expr = nullptr;
-    field->accept_vis (*this);
-    if (resolved_field_value_expr == nullptr)
-      {
-	rust_fatal_error (field->get_locus (),
-			  "failed to resolve type for field");
-	ok = false;
-	return false;
-      }
 
-    context->insert_type (field->get_mappings (), resolved_field_value_expr);
-    return true;
-  });
+  for (auto &field : struct_expr.get_fields ())
+    {
+      resolved_field_value_expr = nullptr;
+      field->accept_vis (*this);
+      if (resolved_field_value_expr == nullptr)
+	{
+	  rust_fatal_error (field->get_locus (),
+			    "failed to resolve type for field");
+	  ok = false;
+	  break;
+	}
+
+      context->insert_type (field->get_mappings (), resolved_field_value_expr);
+    }
 
   // something failed setting up the fields
   if (!ok)
@@ -266,10 +267,8 @@ TypeCheckStructExpr::visit (HIR::StructExprStructFields &struct_expr)
       // correctly. The GIMPLE backend uses a simple algorithm that assumes each
       // assigned field in the constructor is in the same order as the field in
       // the type
-      std::vector<std::unique_ptr<HIR::StructExprField> > expr_fields
-	= struct_expr.get_fields_as_owner ();
-      for (auto &f : expr_fields)
-	f.release ();
+      for (auto &field : struct_expr.get_fields ())
+	field.release ();
 
       std::vector<std::unique_ptr<HIR::StructExprField> > ordered_fields;
       for (size_t i = 0; i < adtFieldIndexToField.size (); i++)
diff --git a/gcc/rust/typecheck/rust-tycheck-dump.h b/gcc/rust/typecheck/rust-tycheck-dump.h
index cc2e3c0..6856d05 100644
--- a/gcc/rust/typecheck/rust-tycheck-dump.h
+++ b/gcc/rust/typecheck/rust-tycheck-dump.h
@@ -162,11 +162,11 @@ public:
 
   void visit (HIR::ArrayElemsValues &elems) override
   {
-    elems.iterate ([&] (HIR::Expr *e) mutable -> bool {
-      e->accept_vis (*this);
-      dump += ",";
-      return true;
-    });
+    for (auto &elem : elems.get_values ())
+      {
+	elem->accept_vis (*this);
+	dump += ",";
+      }
   }
 
   void visit (HIR::GroupedExpr &expr) override