1 files changed, 116 insertions, 0 deletions
diff --git a/gcc/d/dmd/templateparamsem.c b/gcc/d/dmd/templateparamsem.c
new file mode 100644
index 0000000..11cd52e
--- /dev/null
+++ b/gcc/d/dmd/templateparamsem.c
@@ -0,0 +1,116 @@
+
+/* Compiler implementation of the D programming language
+ * Copyright (C) 1999-2021 by The D Language Foundation, All Rights Reserved
+ * written by Walter Bright
+ * http://www.digitalmars.com
+ * Distributed under the Boost Software License, Version 1.0.
+ * http://www.boost.org/LICENSE_1_0.txt
+ */
+
+#include "template.h"
+#include "mtype.h"
+#include "scope.h"
+#include "visitor.h"
+
+bool reliesOnTident(Type *t, TemplateParameters *tparams = NULL, size_t iStart = 0);
+
+class TemplateParameterSemanticVisitor : public Visitor
+{
+public:
+    Scope *sc;
+    TemplateParameters *parameters;
+    bool result;
+
+    TemplateParameterSemanticVisitor(Scope *sc, TemplateParameters *parameters)
+    {
+        this->sc = sc;
+        this->parameters = parameters;
+	this->result = false;
+    }
+
+    void visit(TemplateTypeParameter *ttp)
+    {
+        //printf("TemplateTypeParameter::semantic('%s')\n", ident->toChars());
+        if (ttp->specType && !reliesOnTident(ttp->specType, parameters))
+        {
+            ttp->specType = typeSemantic(ttp->specType, ttp->loc, sc);
+        }
+        result = !(ttp->specType && isError(ttp->specType));
+    }
+
+    void visit(TemplateValueParameter *tvp)
+    {
+        tvp->valType = typeSemantic(tvp->valType, tvp->loc, sc);
+
+        result = !isError(tvp->valType);
+    }
+
+    void visit(TemplateAliasParameter *tap)
+    {
+        if (tap->specType && !reliesOnTident(tap->specType, parameters))
+        {
+            tap->specType = typeSemantic(tap->specType, tap->loc, sc);
+        }
+        tap->specAlias = aliasParameterSemantic(tap->loc, sc, tap->specAlias, parameters);
+        result = !(tap->specType  && isError(tap->specType)) &&
+            !(tap->specAlias && isError(tap->specAlias));
+    }
+
+    void visit(TemplateTupleParameter *)
+    {
+        result = true;
+    }
+};
+
+/************************************************
+ * Performs semantic on TemplateParameter AST nodes.
+ *
+ * Params:
+ *      tp = element of `parameters` to be semantically analyzed
+ *      sc = context
+ *      parameters = array of `TemplateParameters` supplied to the `TemplateDeclaration`
+ * Returns:
+ *      `true` if no errors
+ */
+bool tpsemantic(TemplateParameter *tp, Scope *sc, TemplateParameters *parameters)
+{
+    TemplateParameterSemanticVisitor v(sc, parameters);
+    tp->accept(&v);
+    return v.result;
+}
+
+/***********************************************
+ * Support function for performing semantic analysis on `TemplateAliasParameter`.
+ *
+ * Params:
+ *      loc = location (for error messages)
+ *      sc = context
+ *      o = object to run semantic() on, the `TemplateAliasParameter`s `specAlias` or `defaultAlias`
+ *      parameters = array of `TemplateParameters` supplied to the `TemplateDeclaration`
+ * Returns:
+ *      object resulting from running `semantic` on `o`
+ */
+RootObject *aliasParameterSemantic(Loc loc, Scope *sc, RootObject *o, TemplateParameters *parameters)
+{
+    if (o)
+    {
+        Expression *ea = isExpression(o);
+        Type *ta = isType(o);
+        if (ta && (!parameters || !reliesOnTident(ta, parameters)))
+        {
+            Dsymbol *s = ta->toDsymbol(sc);
+            if (s)
+                o = s;
+            else
+                o = typeSemantic(ta, loc, sc);
+        }
+        else if (ea)
+        {
+            sc = sc->startCTFE();
+            ea = expressionSemantic(ea, sc);
+            sc = sc->endCTFE();
+            o = ea->ctfeInterpret();
+        }
+    }
+    return o;
+}