[GR-45116] Specialize Array#<< and related methods appending elements per call site to have a single array storage strategy in the inline cache for most cases

PullRequest: truffleruby/3969
(cherry picked from commit f541bb2)

Author: eregon

CHANGELOG.md

@@ -48,6 +48,7 @@ Performance:
 
 * Improve `Truffle::FeatureLoader.loaded_feature_path` by removing expensive string ops from a loop. Speeds up feature lookup time (#3010, @itarato).
 * Improve `String#-@` performance by reducing unnecessary data copying and supporting substring lookups (@nirvdrum)
+* Specialize `Array#<<` and related methods appending elements per call site to have a single array storage strategy in the inline cache for most cases (@eregon).
 
 Changes:
 

src/main/java/org/truffleruby/core/array/ArrayAppendOneNode.java

@@ -13,6 +13,7 @@
 import static org.truffleruby.core.array.ArrayHelpers.setStoreAndSize;
 
 import com.oracle.truffle.api.dsl.NeverDefault;
+import com.oracle.truffle.api.dsl.ReportPolymorphism;
 import com.oracle.truffle.api.profiles.CountingConditionProfile;
 import org.truffleruby.core.array.library.ArrayStoreLibrary;
 import org.truffleruby.language.RubyContextSourceNode;
@@ -28,6 +29,7 @@
 @NodeChild(value = "arrayNode", type = RubyNode.class)
 @NodeChild(value = "valueNode", type = RubyNode.class)
 @ImportStatic(ArrayGuards.class)
+@ReportPolymorphism
 public abstract class ArrayAppendOneNode extends RubyContextSourceNode {
 
     @NeverDefault

src/main/ruby/truffleruby/core/gc.rb

@@ -48,13 +48,9 @@ def self.stat_hash(key_or_hash)
         Primitive.gc_stat[3]
       when :unknown_count
         Primitive.gc_stat[4]
-      when :used
+      when :used, :heap_live_slots
         Primitive.gc_stat[5]
-      when :heap_live_slots
-        Primitive.gc_stat[5]
-      when :heap_available_slots
-        Primitive.gc_stat[6]
-      when :committed
+      when :committed, :heap_available_slots
         Primitive.gc_stat[6]
       when :heap_free_slots
         stat = Primitive.gc_stat