profile OrAssignConstantNode

Author: Nicolas Laurent

src/main/java/org/truffleruby/language/constants/OrAssignConstantNode.java

@@ -10,7 +10,9 @@
 package org.truffleruby.language.constants;
 
 import com.oracle.truffle.api.CompilerDirectives;
+import com.oracle.truffle.api.CompilerDirectives.CompilationFinal;
 import com.oracle.truffle.api.frame.VirtualFrame;
+import com.oracle.truffle.api.profiles.ConditionProfile;
 import org.truffleruby.core.cast.BooleanCastNode;
 import org.truffleruby.core.cast.BooleanCastNodeGen;
 import org.truffleruby.core.module.RubyModule;
@@ -29,6 +31,26 @@ public class OrAssignConstantNode extends RubyContextSourceNode {
     @Child protected WriteConstantNode writeConstant;
     @Child private BooleanCastNode cast;
 
+    private enum ExecuteCounter {
+        NEVER,
+        ONCE,
+        MANY;
+
+        public ExecuteCounter next() {
+            if (this == NEVER) {
+                return ONCE;
+            } else {
+                return MANY;
+            }
+        }
+
+    }
+
+    @CompilationFinal private ExecuteCounter executeCounter = ExecuteCounter.NEVER;
+    private final ConditionProfile triviallyUndefined = ConditionProfile.create();
+    private final ConditionProfile defined = ConditionProfile.create();
+    private final ConditionProfile truthy = ConditionProfile.create();
+
     public OrAssignConstantNode(ReadConstantNode readConstant, WriteConstantNode writeConstant) {
         this.readConstant = readConstant;
         this.writeConstant = writeConstant;
@@ -37,7 +59,14 @@ public OrAssignConstantNode(ReadConstantNode readConstant, WriteConstantNode wri
     @Override
     public Object execute(VirtualFrame frame) {
 
-        if (readConstant.isModuleTriviallyUndefined(frame, getLanguage(), getContext())) {
+        if (executeCounter != ExecuteCounter.MANY) {
+            // Make sure to reset the profiles after the first execution, as we expect the first execution to write
+            // the constant and subsequent execution to simply read it.
+            CompilerDirectives.transferToInterpreterAndInvalidate();
+            executeCounter = executeCounter.next();
+        }
+
+        if (triviallyUndefined.profile(readConstant.isModuleTriviallyUndefined(frame, getLanguage(), getContext()))) {
             // It might not be defined because of autoloaded constants (maybe other reasons?),
             // simply attempt writing (which will trigger autoloads if required).
             // Since we didn't evaluate the module part yet, no side-effects can occur.
@@ -53,12 +82,12 @@ public Object execute(VirtualFrame frame) {
 
         // Next we check if the constant itself is defined, and if it is, we get its value.
         final RubyConstant constant = readConstant.getConstantIfDefined(module);
-        final Object value = constant == null
-                ? null
-                : readConstant.getConstant(module, constant);
+        final Object value = defined.profile(constant != null)
+                ? readConstant.getConstant(module, constant)
+                : null;
 
         // Write if the constant is undefined or if its value is falsy.
-        if (constant == null || !castToBoolean(value)) {
+        if (!defined.profile(constant != null) || !truthy.profile(castToBoolean(value))) {
             return writeConstant.execute(frame, module);
         } else {
             return value;