commit 43a1dc799f068daaf5487e92ace90ad65d0560bf
author shreyax <shreyax@google.com> Sat Jun 02 15:08:51 2018 -0700
committer Copybara-Service <copybara-piper@google.com> Sat Jun 02 15:09:58 2018 -0700
tree d8a965f43f61c869aa9dee452a36024bc3a05086
parent ff008f445905bf6f4601a368782b620f7899d322

Fast-path Label#equals by first comparing the interned PackageIdentifier.

PiperOrigin-RevId: 199007753

src/main/java/com/google/devtools/build/lib/cmdline/Label.java

diff --git a/src/main/java/com/google/devtools/build/lib/cmdline/Label.java b/src/main/java/com/google/devtools/build/lib/cmdline/Label.java
index f271ea6..61805ca 100644
--- a/src/main/java/com/google/devtools/build/lib/cmdline/Label.java
+++ b/src/main/java/com/google/devtools/build/lib/cmdline/Label.java
@@ -539,9 +539,8 @@
       return false;
     }
     Label otherLabel = (Label) other;
-    // Perform the equality comparisons in order from least likely to most likely.
-    return name.equals(otherLabel.name)
-        && packageIdentifier.equals(otherLabel.packageIdentifier);
+    // Package identifiers are interned so we compare them first.
+    return packageIdentifier.equals(otherLabel.packageIdentifier) && name.equals(otherLabel.name);
   }
 
   /**

src/main/java/com/google/devtools/build/lib/cmdline/PackageIdentifier.java

diff --git a/src/main/java/com/google/devtools/build/lib/cmdline/PackageIdentifier.java b/src/main/java/com/google/devtools/build/lib/cmdline/PackageIdentifier.java
index d8bf3bf..8d7ad19 100644
--- a/src/main/java/com/google/devtools/build/lib/cmdline/PackageIdentifier.java
+++ b/src/main/java/com/google/devtools/build/lib/cmdline/PackageIdentifier.java
@@ -46,6 +46,7 @@
 
   @AutoCodec.Instantiator
   public static PackageIdentifier create(RepositoryName repository, PathFragment pkgName) {
+    // Note: We rely on these being interned to fast-path Label#equals.
     return INTERNER.intern(new PackageIdentifier(repository, pkgName));
   }