From: Dale Weiler <killfieldengine@gmail.com>
Date: Wed, 6 Feb 2013 05:30:09 +0000 (+0000)
Subject: Implemented generalized attribute aliases.  You can now alias functions, locals,... 
X-Git-Tag: before-library~147
X-Git-Url: https://git.xonotic.org/?p=xonotic%2Fgmqcc.git;a=commitdiff_plain;h=e464cc1ea66ef3ab33226c58ac4ad2ed79fa6eb8

Implemented generalized attribute aliases.  You can now alias functions, locals, or globals with [[alias("old_name")]] type new_name;
---

diff --git a/ast.h b/ast.h
index 83c700a..9b55421 100644
--- a/ast.h
+++ b/ast.h
@@ -151,6 +151,7 @@ typedef struct
 #define AST_FLAG_DEPRECATED   (1<<4)
 #define AST_FLAG_INCLUDE_DEF  (1<<5)
 #define AST_FLAG_IS_VARARG    (1<<6)
+#define AST_FLAG_ALIAS        (1<<7)
 #define AST_FLAG_TYPE_MASK (AST_FLAG_VARIADIC | AST_FLAG_NORETURN)
 
 /* Value
diff --git a/parser.c b/parser.c
index d5f800c..4ba08b4 100644
--- a/parser.c
+++ b/parser.c
@@ -62,6 +62,7 @@ typedef struct {
     size_t crc_fields;
 
     ast_function *function;
+    ht            aliases;
 
     /* All the labels the function defined...
      * Should they be in ast_function instead?
@@ -1825,9 +1826,11 @@ static bool parse_sya_operand(parser_t *parser, shunt *sy, bool with_labels)
             /* intrinsics */
             if (!strcmp(parser_tokval(parser), "__builtin_debug_typestring")) {
                 var = (ast_expression*)intrinsic_debug_typestring;
+            } else {
+                var = (ast_expression*)parser_find_var(parser, (const char *)util_htget(parser->aliases, parser_tokval(parser)));
             }
-            else
-            {
+                
+            if (!var) {
                 char *correct = NULL;
                 size_t i;
 
@@ -2932,8 +2935,44 @@ static bool parse_qualifiers(parser_t *parser, bool with_local, int *cvq, bool *
                     return false;
                 }
             }
+            else if (!strcmp(parser_tokval(parser), "alias") && !(flags & AST_FLAG_ALIAS)) {
+                flags   |= AST_FLAG_ALIAS;
+                *message = NULL;
 
+                if (!parser_next(parser)) {
+                    parseerror(parser, "parse error in attribute");
+                    goto argerr;
+                }
 
+                if (parser->tok == '(') {
+                    if (!parser_next(parser) || parser->tok != TOKEN_STRINGCONST) {
+                        parseerror(parser, "`alias` attribute missing parameter");
+                        goto argerr;
+                    }
+
+                    *message = util_strdup(parser_tokval(parser));
+
+                    if (!parser_next(parser)) {
+                        parseerror(parser, "parse error in attribute");
+                        goto argerr;
+                    }
+
+                    if (parser->tok != ')') {
+                        parseerror(parser, "`alias` attribute expected `)` after parameter");
+                        goto argerr;
+                    }
+
+                    if (!parser_next(parser)) {
+                        parseerror(parser, "parse error in attribute");
+                        goto argerr;
+                    }
+                }
+
+                if (parser->tok != TOKEN_ATTRIBUTE_CLOSE) {
+                    parseerror(parser, "`alias` attribute expected `]]`");
+                    goto argerr;
+                }
+            }
             else if (!strcmp(parser_tokval(parser), "deprecated") && !(flags & AST_FLAG_DEPRECATED)) {
                 flags   |= AST_FLAG_DEPRECATED;
                 *message = NULL;
@@ -3820,6 +3859,11 @@ static bool parse_function_body(parser_t *parser, ast_value *var)
     has_frame_think = false;
     old = parser->function;
 
+    if (var->expression.flags & AST_FLAG_ALIAS) {
+        parseerror(parser, "function aliases cannot have bodies");
+        return false;
+    }
+
     if (vec_size(parser->gotos) || vec_size(parser->labels)) {
         parseerror(parser, "gotos/labels leaking");
         return false;
@@ -5012,7 +5056,13 @@ static bool parse_variable(parser_t *parser, ast_block *localblock, bool nofield
 
         var->cvq = qualifier;
         var->expression.flags |= qflags;
-        if (var->expression.flags & AST_FLAG_DEPRECATED)
+
+        /*
+         * store the vstring back to var for alias and
+         * deprecation messages.
+         */   
+        if (var->expression.flags & AST_FLAG_DEPRECATED ||
+            var->expression.flags & AST_FLAG_ALIAS)
             var->desc = vstring;
 
         /* Part 1:
@@ -5217,11 +5267,15 @@ static bool parse_variable(parser_t *parser, ast_block *localblock, bool nofield
                     }
                 }
                 else {
-                    parser_addglobal(parser, var->name, (ast_expression*)var);
-                    if (isvector) {
-                        for (i = 0; i < 3; ++i) {
-                            parser_addglobal(parser, me[i]->name, (ast_expression*)me[i]);
+                    if (!(var->expression.flags & AST_FLAG_ALIAS)) {
+                        parser_addglobal(parser, var->name, (ast_expression*)var);
+                        if (isvector) {
+                            for (i = 0; i < 3; ++i) {
+                                parser_addglobal(parser, me[i]->name, (ast_expression*)me[i]);
+                            }
                         }
+                    } else {
+                        util_htset(parser->aliases, var->name, (void*)var->desc);
                     }
                 }
             } else {
@@ -5718,6 +5772,8 @@ bool parser_init()
     vec_push(parser->typedefs, util_htnew(TYPEDEF_HT_SIZE));
     vec_push(parser->_blocktypedefs, 0);
 
+    parser->aliases = util_htnew(PARSER_HT_SIZE);
+
     /* corrector */
     vec_push(parser->correct_variables, correct_trie_new());
     vec_push(parser->correct_variables_score, NULL);
@@ -5868,6 +5924,8 @@ void parser_cleanup()
     ast_value_delete(parser->const_vec[1]);
     ast_value_delete(parser->const_vec[2]);
 
+    util_htdel(parser->aliases);
+
     mem_d(parser);
 }
 
diff --git a/tests/aliases.qc b/tests/aliases.qc
new file mode 100644
index 0000000..e66d525
--- /dev/null
+++ b/tests/aliases.qc
@@ -0,0 +1,21 @@
+float alias_1 = 3.14;
+void  alias_2() {
+    print("alias_2\n");
+}
+
+[[alias("alias_2")]] void  alias_2_aliased();
+[[alias("alias_1")]] float alias_1_aliased;
+
+// expected output
+// alias_2
+// 3.14
+void main() {
+    alias_2_aliased();
+
+    print(
+        ftos(
+            alias_1_aliased
+        ),
+        "\n"
+    );
+}
diff --git a/tests/aliases.tmpl b/tests/aliases.tmpl
new file mode 100644
index 0000000..185350f
--- /dev/null
+++ b/tests/aliases.tmpl
@@ -0,0 +1,6 @@
+I: aliases.qc
+D: test aliases
+T: -execute
+C: -std=gmqcc
+M: alias_2
+M: 3.14