From 8a82c183b10cc8e9a7fe6ca279c1d85b77434193 Mon Sep 17 00:00:00 2001
From: Steven van Rossum <sjvanrossum@google.com>
Date: Tue, 2 Dec 2025 11:52:09 +0000
Subject: [PATCH 1/3] Replace VarInt.getLength with Protobuf's branchless
 implementation

---
 .../java/org/apache/beam/sdk/util/VarInt.java   | 17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

diff --git a/sdks/java/core/src/main/java/org/apache/beam/sdk/util/VarInt.java b/sdks/java/core/src/main/java/org/apache/beam/sdk/util/VarInt.java
index 5432383f5ad4..ced3c0f1efbc 100644
--- a/sdks/java/core/src/main/java/org/apache/beam/sdk/util/VarInt.java
+++ b/sdks/java/core/src/main/java/org/apache/beam/sdk/util/VarInt.java
@@ -136,16 +136,19 @@ public static long decodeLong(InputStream stream) throws IOException {
 
   /** Returns the length of the encoding of the given value (in bytes). */
   public static int getLength(int v) {
-    return getLength(convertIntToLongNoSignExtend(v));
+    // log2(v) / 7 + 1 rewritten as multiplication by 9/64 instead of a division by 7.
+    // Log2 is performed using a bit counting instruction.
+    // Multiplication by 9 is performed using a 3-bit left shift and add.
+    // Division by 64 is performed using a 6-bit right shift.
+    return ((Integer.SIZE * 9 + (1 << 6)) - (Integer.numberOfLeadingZeros(v) * 9)) >>> 6;
   }
 
   /** Returns the length of the encoding of the given value (in bytes). */
   public static int getLength(long v) {
-    int result = 0;
-    do {
-      result++;
-      v >>>= 7;
-    } while (v != 0);
-    return result;
+    // log2(v) / 7 + 1 rewritten as multiplication by 9/64 instead of a division by 7.
+    // Log2 is performed using a bit counting instruction.
+    // Multiplication by 9 is performed using a 3-bit left shift and add.
+    // Division by 64 is performed using a 6-bit right shift.
+    return ((Long.SIZE * 9 + (1 << 6)) - (Long.numberOfLeadingZeros(v) * 9)) >>> 6;
   }
 }

From 07b1ee1159c351ee19507196a20cec4a035ec84f Mon Sep 17 00:00:00 2001
From: Steven van Rossum <sjvanrossum@google.com>
Date: Tue, 2 Dec 2025 14:28:31 +0000
Subject: [PATCH 2/3] Use CodedOutputStream's computeUInt32SizeNoTag and
 computeUInt64SizeNoTag

---
 .../main/java/org/apache/beam/sdk/util/VarInt.java  | 13 +++----------
 1 file changed, 3 insertions(+), 10 deletions(-)

diff --git a/sdks/java/core/src/main/java/org/apache/beam/sdk/util/VarInt.java b/sdks/java/core/src/main/java/org/apache/beam/sdk/util/VarInt.java
index ced3c0f1efbc..02ac2586d814 100644
--- a/sdks/java/core/src/main/java/org/apache/beam/sdk/util/VarInt.java
+++ b/sdks/java/core/src/main/java/org/apache/beam/sdk/util/VarInt.java
@@ -21,6 +21,7 @@
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
+import com.google.protobuf.CodedOutputStream;
 
 /**
  * Variable-length encoding for integers.
@@ -136,19 +137,11 @@ public static long decodeLong(InputStream stream) throws IOException {
 
   /** Returns the length of the encoding of the given value (in bytes). */
   public static int getLength(int v) {
-    // log2(v) / 7 + 1 rewritten as multiplication by 9/64 instead of a division by 7.
-    // Log2 is performed using a bit counting instruction.
-    // Multiplication by 9 is performed using a 3-bit left shift and add.
-    // Division by 64 is performed using a 6-bit right shift.
-    return ((Integer.SIZE * 9 + (1 << 6)) - (Integer.numberOfLeadingZeros(v) * 9)) >>> 6;
+    return CodedOutputStream.computeUInt32SizeNoTag(v);
   }
 
   /** Returns the length of the encoding of the given value (in bytes). */
   public static int getLength(long v) {
-    // log2(v) / 7 + 1 rewritten as multiplication by 9/64 instead of a division by 7.
-    // Log2 is performed using a bit counting instruction.
-    // Multiplication by 9 is performed using a 3-bit left shift and add.
-    // Division by 64 is performed using a 6-bit right shift.
-    return ((Long.SIZE * 9 + (1 << 6)) - (Long.numberOfLeadingZeros(v) * 9)) >>> 6;
+    return CodedOutputStream.computeUInt64SizeNoTag(v);
   }
 }

From f859813c8065879068f4b3425e19a3b51f5b0696 Mon Sep 17 00:00:00 2001
From: Steven van Rossum <sjvanrossum@google.com>
Date: Wed, 3 Dec 2025 11:33:34 +0000
Subject: [PATCH 3/3] Run spotless

---
 .../core/src/main/java/org/apache/beam/sdk/util/VarInt.java     | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sdks/java/core/src/main/java/org/apache/beam/sdk/util/VarInt.java b/sdks/java/core/src/main/java/org/apache/beam/sdk/util/VarInt.java
index 02ac2586d814..39719d772957 100644
--- a/sdks/java/core/src/main/java/org/apache/beam/sdk/util/VarInt.java
+++ b/sdks/java/core/src/main/java/org/apache/beam/sdk/util/VarInt.java
@@ -17,11 +17,11 @@
  */
 package org.apache.beam.sdk.util;
 
+import com.google.protobuf.CodedOutputStream;
 import java.io.EOFException;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
-import com.google.protobuf.CodedOutputStream;
 
 /**
  * Variable-length encoding for integers.