Add threadvar section for thread-local variables

6 files changed, 29 insertions, 0 deletions

diff --git a/boot/lexer.ll b/boot/lexer.ll
index 89eb4ed..1cccd35 100644
--- a/boot/lexer.ll
+++ b/boot/lexer.ll
@@ -134,6 +134,9 @@ const {
 var {
     return yy::parser::make_VAR(this->location);
 }
+threadvar {
+    return yy::parser::make_THREADVAR(this->location);
+}
 type {
     return yy::parser::make_TYPE(this->location);
 }
diff --git a/boot/name_analysis.cc b/boot/name_analysis.cc
index d5b2e91..8820684 100644
--- a/boot/name_analysis.cc
+++ b/boot/name_analysis.cc
@@ -1419,6 +1419,7 @@ namespace elna::boot
             variable_symbol->alignment =
                 evaluate_attributes<attribute_kind::aligned>(variable_identifier.attributes).alignment;
             variable_symbol->value = computed;
+            variable_symbol->is_thread_local = declaration->is_thread_local;
         }
     }
 
diff --git a/boot/parser.yy b/boot/parser.yy
index 68af60e..ab386fe 100644
--- a/boot/parser.yy
+++ b/boot/parser.yy
@@ -100,6 +100,7 @@ along with GCC; see the file COPYING3.  If not see
     NIL "nil"
     CONST "const"
     VAR "var"
+    THREADVAR "threadvar"
     PROCEDURE "proc"
     TYPE "type"
     RECORD "record"
@@ -191,6 +192,16 @@ module_declaration:
 
             $$.insert($$.end(), variables.begin(), variables.end());
         }
+    | "threadvar" variable_declarations
+        {
+            std::vector<boot::variable_declaration *> variables = $2;
+
+            for (boot::variable_declaration *const variable : variables)
+            {
+                variable->is_thread_local = true;
+            }
+            $$.insert($$.end(), variables.begin(), variables.end());
+        }
     | procedure_declaration { $$.emplace_back($1); }
 module_declarations:
     %empty {}
diff --git a/gcc/gcc/elna-builtins.cc b/gcc/gcc/elna-builtins.cc
index a8e54c8..365ddb9 100644
--- a/gcc/gcc/elna-builtins.cc
+++ b/gcc/gcc/elna-builtins.cc
@@ -20,6 +20,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "elna/gcc/elna1.h"
 #include "stor-layout.h"
 #include "stringpool.h"
+#include "varasm.h"
 
 #include "elna/boot/evaluator.h"
 #include "elna/gcc/elna-tree.h"
@@ -413,6 +414,13 @@ namespace elna::gcc
 
                 DECL_EXTERNAL(declaration_tree) =
                     static_cast<unsigned>(imported || variable_info->is_extern);
+
+                // The model depends on the linkage, so it is chosen after
+                // DECL_EXTERNAL is final.
+                if (variable_info->is_thread_local)
+                {
+                    set_decl_tls_model(declaration_tree, decl_default_tls_model(declaration_tree));
+                }
             }
             else if (auto procedure_info = symbol_info->is_procedure())
             {
diff --git a/include/elna/boot/ast.h b/include/elna/boot/ast.h
index 5d5bdce..ffc57de 100644
--- a/include/elna/boot/ast.h
+++ b/include/elna/boot/ast.h
@@ -606,6 +606,9 @@ namespace elna::boot
         type_expression& variable_type();
         expression *initializer{ nullptr };
         const bool is_extern{ false };
+
+        /// Whether the variable was declared in a \c threadvar section.
+        bool is_thread_local{ false };
     };
 
     /**
diff --git a/include/elna/boot/symbol.h b/include/elna/boot/symbol.h
index 1ca5deb..08292bc 100644
--- a/include/elna/boot/symbol.h
+++ b/include/elna/boot/symbol.h
@@ -487,6 +487,9 @@ namespace elna::boot
         /// its type's own alignment.
         std::optional<std::size_t> alignment;
 
+        /// Whether the variable has thread storage duration.
+        bool is_thread_local{ false };
+
         /**
          * Constructs a variable symbol information.
          *