Disable string interning for label name attribute value

Weak interner inside `StringCanonicalizer` does have some memory overhead. Some strings only have one instance during a blaze build. And thus, interning these strings introduces memory overhead from the additional `Map.entry` inside weak interner's `ConcurrentHashMap`.

One obvious example of these strings is the label name. It is rarely that label name duplicate with each other. So this cl avoids interning label name (attribute `name`'s value) in order to get rid of the additional map entries.

PiperOrigin-RevId: 540018375
Change-Id: I6bcfb4349b6f45927de51537c8cc091228d1012e

src/main/java/com/google/devtools/build/lib/packages/AttributeFormatter.java

@@ -33,6 +33,7 @@
 import static com.google.devtools.build.lib.packages.Type.STRING_DICT;
 import static com.google.devtools.build.lib.packages.Type.STRING_LIST;
 import static com.google.devtools.build.lib.packages.Type.STRING_LIST_DICT;
+import static com.google.devtools.build.lib.packages.Type.STRING_NO_INTERN;
 
 import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableSet;
@@ -59,6 +60,7 @@ public class AttributeFormatter {
   private static final ImmutableSet<Type<?>> depTypes =
       ImmutableSet.of(
           STRING,
+          STRING_NO_INTERN,
           LABEL,
           OUTPUT,
           STRING_LIST,
@@ -196,11 +198,11 @@ private static void writeAttributeValueToBuilder(
     if (type == INTEGER) {
       builder.setIntValue(((StarlarkInt) value).toIntUnchecked());
     } else if (type == STRING
+        || type == STRING_NO_INTERN
         || type == LABEL
         || type == NODEP_LABEL
         || type == OUTPUT
         || type == GENQUERY_SCOPE_TYPE) {
-
       builder.setStringValue(value.toString());
     } else if (type == STRING_LIST
         || type == LABEL_LIST

src/main/java/com/google/devtools/build/lib/packages/ImplicitOutputsFunction.java

@@ -361,6 +361,8 @@ private static ImmutableSet<String> attributeValues(AttributeMap rule, String at
     // String attributes and lists are easy.
     if (Type.STRING == attrType) {
       return ImmutableSet.of(rule.get(attrName, Type.STRING));
+    } else if (Type.STRING_NO_INTERN == attrType) {
+      return ImmutableSet.of(rule.get(attrName, Type.STRING_NO_INTERN));
     } else if (Type.STRING_LIST == attrType) {
       return ImmutableSet.copyOf(rule.get(attrName, Type.STRING_LIST));
     } else if (BuildType.LABEL == attrType) {

src/main/java/com/google/devtools/build/lib/packages/ProtoUtils.java

@@ -34,6 +34,7 @@
 import static com.google.devtools.build.lib.packages.Type.STRING_DICT;
 import static com.google.devtools.build.lib.packages.Type.STRING_LIST;
 import static com.google.devtools.build.lib.packages.Type.STRING_LIST_DICT;
+import static com.google.devtools.build.lib.packages.Type.STRING_NO_INTERN;
 
 import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableMap;
@@ -55,6 +56,7 @@ public class ProtoUtils {
           .put(GENQUERY_SCOPE_TYPE_LIST, Discriminator.LABEL_LIST)
           .put(NODEP_LABEL_LIST, Discriminator.STRING_LIST)
           .put(STRING, Discriminator.STRING)
+          .put(STRING_NO_INTERN, Discriminator.STRING)
           .put(STRING_LIST, Discriminator.STRING_LIST)
           .put(OUTPUT, Discriminator.OUTPUT)
           .put(OUTPUT_LIST, Discriminator.OUTPUT_LIST)

src/main/java/com/google/devtools/build/lib/packages/RuleClass.java

@@ -18,7 +18,7 @@
 import static com.google.devtools.build.lib.packages.Attribute.attr;
 import static com.google.devtools.build.lib.packages.BuildType.LABEL_LIST;
 import static com.google.devtools.build.lib.packages.Type.BOOLEAN;
-import static com.google.devtools.build.lib.packages.Type.STRING;
+import static com.google.devtools.build.lib.packages.Type.STRING_NO_INTERN;
 
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Function;
@@ -124,7 +124,7 @@ public class RuleClass {
 
   /** The name attribute, present for all rules at index 0. */
   static final Attribute NAME_ATTRIBUTE =
-      attr("name", STRING)
+      attr("name", STRING_NO_INTERN)
           .nonconfigurable("All rules have a non-customizable \"name\" attribute")
           .build();
 

src/main/java/com/google/devtools/build/lib/packages/Type.java

@@ -240,8 +240,23 @@ public Set<String> toTagSet(Object value, String name) {
   /** The type of a Starlark integer in the signed 32-bit range. */
   @SerializationConstant public static final Type<StarlarkInt> INTEGER = new IntegerType();
 
-  /** The type of a string. */
-  @SerializationConstant public static final Type<String> STRING = new StringType();
+  /**
+   * The type of a string which interns the string instance in {@link StringCanonicalizer}'s weak
+   * interner.
+   */
+  @SerializationConstant
+  public static final Type<String> STRING = new StringType(/* internString= */ true);
+
+  /**
+   * The type of a string which does not intern the string instance.
+   *
+   * <p>When there is only one string instance created in blaze, interning it introduces memory
+   * overhead of an additional map entry in weak interner's map. So for attribute whose string value
+   * tends to not duplicate (for example rule name), it is preferable not to intern such string
+   * values.
+   */
+  @SerializationConstant
+  public static final Type<String> STRING_NO_INTERN = new StringType(/* internString= */ false);
 
   /** The type of a boolean. */
   @SerializationConstant public static final Type<Boolean> BOOLEAN = new BooleanType();
@@ -438,6 +453,12 @@ public Set<String> toTagSet(Object value, String name) {
   }
 
   private static final class StringType extends Type<String> {
+    private final boolean internString;
+
+    public StringType(boolean internString) {
+      this.internString = internString;
+    }
+
     @Override
     public String cast(Object value) {
       return (String) value;
@@ -462,7 +483,7 @@ public String convert(Object x, Object what, LabelConverter labelConverter)
       if (!(x instanceof String)) {
         throw new ConversionException(this, x, what);
       }
-      return StringCanonicalizer.intern((String) x);
+      return internString ? StringCanonicalizer.intern((String) x) : (String) x;
     }
 
     @Override