Convert StringAppendNode to DSL inlinable node

Author: horakivo

src/main/java/org/truffleruby/core/string/StringHelperNodes.java

@@ -592,22 +592,18 @@ static int getCodePoint(Node node, AbstractTruffleString string, RubyEncoding en
 
     }
 
+    @GenerateInline
+    @GenerateCached(false)
     public abstract static class StringAppendNode extends RubyBaseNode {
 
-        @NeverDefault
-        public static StringAppendNode create() {
-            return StringHelperNodesFactory.StringAppendNodeGen.create();
-        }
-
-        public abstract RubyString executeStringAppend(Object string, Object other);
+        public abstract RubyString executeStringAppend(Node node, Object string, Object other);
 
         @Specialization(guards = "libOther.isRubyString(other)", limit = "1")
-        static RubyString stringAppend(Object string, Object other,
+        static RubyString stringAppend(Node node, Object string, Object other,
                 @Cached RubyStringLibrary libString,
                 @Cached RubyStringLibrary libOther,
                 @Cached EncodingNodes.CheckStringEncodingNode checkEncodingNode,
-                @Cached TruffleString.ConcatNode concatNode,
-                @Bind("this") Node node) {
+                @Cached(inline = false) TruffleString.ConcatNode concatNode) {
 
             var left = libString.getTString(string);
             var leftEncoding = libString.getEncoding(string);

src/main/java/org/truffleruby/core/string/StringNodes.java

@@ -222,7 +222,7 @@ RubyString add(Object string, Object other,
                 @Cached ToStrNode toStrNode,
                 @Cached StringHelperNodes.StringAppendNode stringAppendNode) {
             final var otherAsString = toStrNode.execute(this, other);
-            return stringAppendNode.executeStringAppend(string, otherAsString);
+            return stringAppendNode.executeStringAppend(this, string, otherAsString);
         }
     }
 
@@ -3105,9 +3105,6 @@ protected boolean isMBCPrintable(Encoding encoding, int codePoint) {
     @Primitive(name = "string_append")
     public abstract static class StringAppendPrimitiveNode extends PrimitiveArrayArgumentsNode {
 
-        @Child private StringHelperNodes.StringAppendNode stringAppendNode = StringHelperNodes.StringAppendNode
-                .create();
-
         @NeverDefault
         public static StringAppendPrimitiveNode create() {
             return StringAppendPrimitiveNodeFactory.create(null);
@@ -3116,8 +3113,9 @@ public static StringAppendPrimitiveNode create() {
         public abstract RubyString executeStringAppend(RubyString string, Object other);
 
         @Specialization
-        RubyString stringAppend(RubyString string, Object other) {
-            final RubyString result = stringAppendNode.executeStringAppend(string, other);
+        RubyString stringAppend(RubyString string, Object other,
+                @Cached StringHelperNodes.StringAppendNode stringAppendNode) {
+            final RubyString result = stringAppendNode.executeStringAppend(this, string, other);
             string.setTString(result.tstring, result.getEncodingUnprofiled());
             return string;
         }