Implement string comparison

include/elna/gcc/elna-builtins.h

@@ -1,3 +1,20 @@
+/* Builtin definitions.
+   Copyright (C) 2025 Free Software Foundation, Inc.
+
+GCC is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 3, or (at your option)
+any later version.
+
+GCC is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GCC; see the file COPYING3.  If not see
+<http://www.gnu.org/licenses/>.  */
+
 #include "config.h"
 #include "system.h"
 #include "coretypes.h"

include/elna/gcc/elna-generic.h

@@ -36,7 +36,6 @@ namespace gcc
 {
     class generic_visitor final : public boot::empty_visitor
     {
-        std::forward_list<block_scope> scope;
         tree current_expression{ NULL_TREE };
         std::shared_ptr<boot::symbol_table<tree>> symbol_map;
 
@@ -44,22 +43,19 @@ namespace gcc
         tree build_type(boot::type_expression& type);
 
         void enter_scope();
-        tree_symbol_mapping leave_scope();
+        tree leave_scope();
 
         tree lookup(const std::string& name);
 
         void make_if_branch(boot::conditional_statements& branch, tree goto_endif);
 
-        bool is_numeric_type(tree type);
-
         tree build_arithmetic_operation(boot::binary_expression *expression,
                 tree_code operator_code, tree left, tree right);
         tree build_comparison_operation(boot::binary_expression *expression,
                 tree_code operator_code, tree left, tree right);
         tree build_logic_operation(boot::binary_expression *expression,
                 tree_code operator_code, tree left, tree right);
-        tree build_equality_operation(boot::binary_expression *expression,
-                tree_code operator_code, tree left, tree right);
+        tree build_equality_operation(boot::binary_expression *expression, tree left, tree right);
 
     public:
         generic_visitor(std::shared_ptr<boot::symbol_table<tree>> symbol_table);

include/elna/gcc/elna-tree.h

@@ -35,6 +35,7 @@ namespace gcc
 {
     bool is_pointer_type(tree type);
     bool is_integral_type(tree type);
+    bool is_numeric_type(tree type);
 
     /**
      * \param lhs Left hand value.
@@ -43,59 +44,9 @@ namespace gcc
      */
     bool are_compatible_pointers(tree lhs, tree rhs);
 
-    class tree_chain_base
-    {
-    protected:
-        tree first{};
-        tree last{};
-
-    public:
-        tree head();
-        void append(tree t);
-
-    protected:
-        virtual void chain(tree t) = 0;
-    };
-
-    class tree_chain final : public tree_chain_base
-    {
-    protected:
-        void chain(tree t) override;
-    };
-
-    class block_chain final : public tree_chain_base
-    {
-    protected:
-        void chain(tree t) override;
-    };
-
-    class tree_symbol_mapping final
-    {
-        tree m_bind_expression;
-        tree m_block;
-
-    public:
-        tree_symbol_mapping(tree bind_expression, tree block);
-
-        tree bind_expression();
-        tree block();
-    };
-
-    class block_scope
-    {
-        tree m_statement_list{ NULL_TREE };
-        std::forward_list<std::pair<tree, tree>> defers;
-
-    public:
-        tree_chain variables;
-        block_chain blocks;
-
-        block_scope();
-
-        void append_statement(tree statement_tree);
-        void defer(tree statement_tree);
-        tree chain_defer();
-    };
+    void append_statement(tree statement_tree);
+    void defer(tree statement_tree);
+    tree chain_defer();
 
     tree do_pointer_arithmetic(boot::binary_operator binary_operator, tree left, tree right);
     tree build_binary_operation(bool condition, boot::binary_expression *expression,

include/elna/gcc/elna1.h

@@ -1,3 +1,20 @@
+/* Language-dependent hooks for Elna.
+   Copyright (C) 2025 Free Software Foundation, Inc.
+
+GCC is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 3, or (at your option)
+any later version.
+
+GCC is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GCC; see the file COPYING3.  If not see
+<http://www.gnu.org/licenses/>.  */
+
 enum elna_tree_index
 {
     ELNA_TI_INT_TYPE,
@@ -11,6 +28,7 @@ enum elna_tree_index
 };
 
 extern GTY(()) tree elna_global_trees[ELNA_TI_MAX];
+extern GTY(()) hash_map<nofree_string_hash, tree> *elna_global_decls;
 
 #define elna_int_type_node elna_global_trees[ELNA_TI_INT_TYPE]
 #define elna_word_type_node elna_global_trees[ELNA_TI_WORD_TYPE]
@@ -30,18 +48,35 @@ struct GTY (()) lang_decl
 {
 };
 
-struct GTY (()) binding_level
+struct GTY (()) defer_scope
 {
-    // A chain of all declarations in this binding level.
-    tree names;
+    tree defer_block;
+    tree try_statements;
+};
+
+struct GTY ((chain_next ("%h.level_chain"))) binding_level
+{
+    // A block chain is needed to call defer statements beloning to each block.
+    tree blocks;
+
+    // Parent level.
+    struct binding_level *level_chain;
+
+    // Statements before the first defer has been seen.
+    tree statement_list;
+
+    // Defer statement coupled with statements following it.
+    vec<defer_scope, va_gc> *defers;
 };
 
 struct GTY (()) language_function
 {
+    // Local variables and constants.
+    tree names;
+
+    // Lexical scope.
     struct binding_level *binding_level;
 };
 
 #define f_binding_level DECL_STRUCT_FUNCTION(current_function_decl)->language->binding_level
-
-extern tree pushdecl(tree);
-extern tree getdecls(void);
+#define f_names DECL_STRUCT_FUNCTION(current_function_decl)->language->names