Rephrase AbstractAttributeMapper#visitLabels such that we can avoid creating a temporary Type.LabelVisitor instance per Attribute being visited. Instead, we can now create one temporary object per visitation. Getting rid of this dimension of scaling reduces the amount of garbage created.

RELNOTES: None

PiperOrigin-RevId: 152161836

1 files changed, 14 insertions, 10 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/packages/BuildType.java b/src/main/java/com/google/devtools/build/lib/packages/BuildType.java
index 263fe63e79..5df9d83625 100644
--- a/src/main/java/com/google/devtools/build/lib/packages/BuildType.java
+++ b/src/main/java/com/google/devtools/build/lib/packages/BuildType.java
@@ -30,6 +30,7 @@ import com.google.devtools.build.lib.syntax.Type;
 import com.google.devtools.build.lib.syntax.Type.ConversionException;
 import com.google.devtools.build.lib.syntax.Type.DictType;
 import com.google.devtools.build.lib.syntax.Type.LabelClass;
+import com.google.devtools.build.lib.syntax.Type.LabelVisitor;
 import com.google.devtools.build.lib.syntax.Type.ListType;
 import java.util.ArrayList;
 import java.util.Collections;
@@ -103,7 +104,7 @@ public final class BuildType {
     }
 
     @Override
-    public void visitLabels(LabelVisitor visitor, Object value) {
+    public <T> void visitLabels(LabelVisitor<T> visitor, Object value, T context) {
     }
 
     @Override
@@ -200,9 +201,10 @@ public final class BuildType {
     }
 
     @Override
-    public void visitLabels(LabelVisitor visitor, Object value) throws InterruptedException {
+    public <T> void visitLabels(LabelVisitor<T> visitor, Object value, T context)
+        throws InterruptedException {
       for (Label label : cast(value).getLabels()) {
-        visitor.visit(label);
+        visitor.visit(label, context);
       }
     }
   }
@@ -225,8 +227,9 @@ public final class BuildType {
     }
 
     @Override
-    public void visitLabels(LabelVisitor visitor, Object value) throws InterruptedException {
-      visitor.visit(cast(value));
+    public <T> void visitLabels(LabelVisitor<T> visitor, Object value, T context)
+        throws InterruptedException {
+      visitor.visit(cast(value), context);
     }
 
     @Override
@@ -345,7 +348,7 @@ public final class BuildType {
     }
 
     @Override
-    public void visitLabels(LabelVisitor visitor, Object value) {
+    public <T> void visitLabels(LabelVisitor<T> visitor, Object value, T context) {
     }
 
     @Override
@@ -384,7 +387,7 @@ public final class BuildType {
     }
 
     @Override
-    public void visitLabels(LabelVisitor visitor, Object value) {
+    public <T> void visitLabels(LabelVisitor<T> visitor, Object value, T context) {
     }
 
     @Override
@@ -410,8 +413,9 @@ public final class BuildType {
     }
 
     @Override
-    public void visitLabels(LabelVisitor visitor, Object value) throws InterruptedException {
-      visitor.visit(cast(value));
+    public <T> void visitLabels(LabelVisitor<T> visitor, Object value, T context)
+        throws InterruptedException {
+      visitor.visit(cast(value), context);
     }
 
     @Override
@@ -676,7 +680,7 @@ public final class BuildType {
     }
 
     @Override
-    public void visitLabels(LabelVisitor visitor, Object value) {
+    public <T> void visitLabels(LabelVisitor<T> visitor, Object value, T context) {
     }
 
     @Override