[mtype.d] Devirtualise Type.equals (#21785)

thewilsonator · web-flow · commit 50346ab4db1d · 2025-08-27T10:21:56.000+08:00
diff --git a/compiler/src/dmd/frontend.h b/compiler/src/dmd/frontend.h
@@ -2079,7 +2079,7 @@ class Type : public ASTNode
     virtual const char* kind() const;
     Type* copy() const;
     virtual Type* syntaxCopy();
-    virtual bool equals(const Type* const t) const;
+    bool equals(const Type* const t) const;
     DYNCAST dyncast() const final override;
     size_t getUniqueID() const;
     const char* toChars() const final override;
@@ -4876,7 +4876,6 @@ class TypeTuple final : public Type
     static TypeTuple* create(Type* t1, Type* t2);
     const char* kind() const override;
     TypeTuple* syntaxCopy() override;
-    bool equals(const Type* const t) const override;
     void accept(Visitor* v) override;
 };
 
diff --git a/compiler/src/dmd/mtype.d b/compiler/src/dmd/mtype.d
@@ -424,12 +424,31 @@ extern (C++) abstract class Type : ASTNode
         assert(0);
     }
 
-    bool equals(const Type t) const
+    final bool equals(const Type t) const
     {
         //printf("Type::equals(%s, %s)\n", toChars(), t.toChars());
+        if (this == t)
+            return true;
+        if (ty == Ttuple)
+        {
+            if (t.ty != Ttuple)
+                return false;
+            auto t1 = this.isTypeTuple();
+            auto t2 = t.isTypeTuple();
+            if (t1.arguments.length != t2.arguments.length)
+                return false;
+            for (size_t i = 0; i < t1.arguments.length; i++)
+            {
+                const Parameter arg1 = (*t1.arguments)[i];
+                const Parameter arg2 = (*t2.arguments)[i];
+                if (!arg1.type.equals(arg2.type))
+                    return false;
+            }
+            return true;
+        }
         // deco strings are unique
         // and semantic() has been run
-        if (this == t || ((t && deco == t.deco) && deco !is null))
+        if ((t && deco == t.deco) && deco !is null)
         {
             //printf("deco = '%s', t.deco = '%s'\n", deco, t.deco);
             return true;
@@ -3330,28 +3349,6 @@ extern (C++) final class TypeTuple : Type
         return t;
     }
 
-    override bool equals(const Type t) const
-    {
-        //printf("TypeTuple::equals(%s, %s)\n", toChars(), t.toChars());
-        if (this == t)
-            return true;
-        if (auto tt = t.isTypeTuple())
-        {
-            if (arguments.length == tt.arguments.length)
-            {
-                for (size_t i = 0; i < tt.arguments.length; i++)
-                {
-                    const Parameter arg1 = (*arguments)[i];
-                    const Parameter arg2 = (*tt.arguments)[i];
-                    if (!arg1.type.equals(arg2.type))
-                        return false;
-                }
-                return true;
-            }
-        }
-        return false;
-    }
-
     override void accept(Visitor v)
     {
         v.visit(this);
diff --git a/compiler/src/dmd/mtype.h b/compiler/src/dmd/mtype.h
@@ -218,7 +218,7 @@ class Type : public ASTNode
     virtual const char *kind();
     Type *copy() const;
     virtual Type *syntaxCopy();
-    virtual bool equals(const Type * const t) const;
+    bool equals(const Type * const t) const;
     // kludge for template.isType()
     DYNCAST dyncast() const override final { return DYNCAST_TYPE; }
     size_t getUniqueID() const;
@@ -759,7 +759,6 @@ class TypeTuple final : public Type
     static TypeTuple *create(Type *t1, Type *t2);
     const char *kind() override;
     TypeTuple *syntaxCopy() override;
-    bool equals(const Type * const t) const override;
     void accept(Visitor *v) override { v->visit(this); }
 };
 
