Inline caching for Encoding#{ascii_compatible?,dummy?} does not seem useful

* It's just two field reads.

Author: eregon

src/main/java/org/truffleruby/core/encoding/EncodingNodes.java

@@ -67,20 +67,8 @@ public abstract class EncodingNodes {
 
     @CoreMethod(names = "ascii_compatible?")
     public abstract static class AsciiCompatibleNode extends CoreMethodArrayArgumentsNode {
-
-        @Specialization(guards = "encoding == cachedEncoding", limit = "getIdentityCacheLimit()")
-        protected boolean isAsciiCompatibleCached(RubyEncoding encoding,
-                @Cached("encoding") RubyEncoding cachedEncoding,
-                @Cached("isAsciiCompatible(cachedEncoding)") boolean isAsciiCompatible) {
-            return isAsciiCompatible;
-        }
-
-        @Specialization(replaces = "isAsciiCompatibleCached")
-        protected boolean isAsciiCompatibleUncached(RubyEncoding encoding) {
-            return isAsciiCompatible(encoding);
-        }
-
-        protected static boolean isAsciiCompatible(RubyEncoding encoding) {
+        @Specialization
+        protected boolean isAsciiCompatible(RubyEncoding encoding) {
             return encoding.encoding.isAsciiCompatible();
         }
     }
@@ -432,29 +420,18 @@ protected ImmutableRubyString localeCharacterMap(
 
     @CoreMethod(names = "dummy?")
     public abstract static class DummyNode extends CoreMethodArrayArgumentsNode {
-
-        @Specialization(guards = "encoding == cachedEncoding", limit = "getIdentityCacheLimit()")
-        protected boolean isDummyCached(RubyEncoding encoding,
-                @Cached("encoding") RubyEncoding cachedEncoding,
-                @Cached("isDummyUncached(cachedEncoding)") boolean isDummy) {
-            return isDummy;
-        }
-
-        @Specialization(replaces = "isDummyCached")
-        protected boolean isDummyUncached(RubyEncoding encoding) {
+        @Specialization
+        protected boolean isDummy(RubyEncoding encoding) {
             return encoding.encoding.isDummy();
         }
-
     }
 
     @CoreMethod(names = { "name", "to_s" })
     public abstract static class ToSNode extends CoreMethodArrayArgumentsNode {
-
         @Specialization
         protected ImmutableRubyString toS(RubyEncoding encoding) {
             return encoding.name;
         }
-
     }
 
     @CoreMethod(names = { "__allocate__", "__layout_allocate__" }, constructor = true, visibility = Visibility.PRIVATE)
@@ -491,12 +468,10 @@ protected Object eachAlias(RubyProc block) {
 
     @Primitive(name = "encoding_is_unicode")
     public abstract static class IsUnicodeNode extends PrimitiveArrayArgumentsNode {
-
         @Specialization
         protected boolean isUnicode(RubyEncoding encoding) {
             return encoding.encoding.isUnicode();
         }
-
     }
 
     @Primitive(name = "get_actual_encoding")
@@ -756,22 +731,18 @@ private RubyEncoding createDummy(String name) {
 
     @Primitive(name = "encoding_get_encoding_by_index", lowerFixnum = 0)
     public static abstract class GetEncodingObjectByIndexNode extends PrimitiveArrayArgumentsNode {
-
         @Specialization
         protected RubyEncoding getEncoding(int index) {
             return getContext().getEncodingManager().getRubyEncoding(index);
         }
-
     }
 
     @Primitive(name = "encoding_get_encoding_index")
     public static abstract class GetEncodingIndexNode extends PrimitiveArrayArgumentsNode {
-
         @Specialization
         protected int getIndex(RubyEncoding encoding) {
             return encoding.encoding.getIndex();
         }
-
     }
 
     public static abstract class CheckRopeEncodingNode extends RubyContextNode {

test/truffle/compiler/pe/core/encoding_pe.rb

@@ -6,12 +6,6 @@
 # GNU General Public License version 2, or
 # GNU Lesser General Public License version 2.1.
 
-example "Encoding::US_ASCII.ascii_compatible?", true
-example "Encoding::UTF_16BE.ascii_compatible?", false
-
-example "Encoding::ISO_2022_JP.dummy?", true
-example "Encoding::UTF_8.dummy?", false
-
 example "Encoding.compatible?('abc', 'def')", Encoding::UTF_8
 example "Encoding.compatible?(Encoding::UTF_8, Encoding::US_ASCII)", Encoding::UTF_8
 example "Encoding.compatible?(Encoding::UTF_8, Encoding::ASCII_8BIT)", nil