From deafa792eb3805f69ecc652a7901056ce2edb4bc Mon Sep 17 00:00:00 2001
From: Zhi Dou <zhidou@google.com>
Date: Tue, 5 Sep 2023 18:22:46 +0000
Subject: [PATCH] aconfig: flag java lib enable optimization

This change adds annotation in the generated code. If the flag is read
only, annotations @com.android.aconfig.annotations.AssumeTrueForR8 or
@com.android.aconfig.annotations.AssumeFalseForR8 will be added in to
the corresponding methods in the interface FeatureFlags, and class
Flags.

Test: atest aconfig aconfig.test.java
Bug: 295328116
Change-Id: Ic1b62a86f0945a5e72ae2c4987cce77fe3f172e9
---
 tools/aconfig/src/codegen_java.rs                  | 6 ++++++
 tools/aconfig/templates/FeatureFlags.java.template | 7 +++++++
 tools/aconfig/templates/Flags.java.template        | 9 ++++++++-
 3 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/tools/aconfig/src/codegen_java.rs b/tools/aconfig/src/codegen_java.rs
index 7cdf4869b2..c31d715867 100644
--- a/tools/aconfig/src/codegen_java.rs
+++ b/tools/aconfig/src/codegen_java.rs
@@ -119,9 +119,12 @@ mod tests {
     const EXPECTED_FEATUREFLAGS_COMMON_CONTENT: &str = r#"
     package com.android.aconfig.test;
     public interface FeatureFlags {
+        @com.android.aconfig.annotations.AssumeFalseForR8
         boolean disabledRo();
         boolean disabledRw();
+        @com.android.aconfig.annotations.AssumeTrueForR8
         boolean enabledFixedRo();
+        @com.android.aconfig.annotations.AssumeTrueForR8
         boolean enabledRo();
         boolean enabledRw();
     }
@@ -136,15 +139,18 @@ mod tests {
         public static final String FLAG_ENABLED_RO = "com.android.aconfig.test.enabled_ro";
         public static final String FLAG_ENABLED_RW = "com.android.aconfig.test.enabled_rw";
 
+        @com.android.aconfig.annotations.AssumeFalseForR8
         public static boolean disabledRo() {
             return FEATURE_FLAGS.disabledRo();
         }
         public static boolean disabledRw() {
             return FEATURE_FLAGS.disabledRw();
         }
+        @com.android.aconfig.annotations.AssumeTrueForR8
         public static boolean enabledFixedRo() {
             return FEATURE_FLAGS.enabledFixedRo();
         }
+        @com.android.aconfig.annotations.AssumeTrueForR8
         public static boolean enabledRo() {
             return FEATURE_FLAGS.enabledRo();
         }
diff --git a/tools/aconfig/templates/FeatureFlags.java.template b/tools/aconfig/templates/FeatureFlags.java.template
index e0f201fc88..31cfdfce8d 100644
--- a/tools/aconfig/templates/FeatureFlags.java.template
+++ b/tools/aconfig/templates/FeatureFlags.java.template
@@ -2,6 +2,13 @@ package {package_name};
 
 public interface FeatureFlags \{
 {{ for item in class_elements}}
+{{ -if not item.is_read_write }}
+{{ -if item.default_value }}
+    @com.android.aconfig.annotations.AssumeTrueForR8
+{{ -else }}
+    @com.android.aconfig.annotations.AssumeFalseForR8
+{{ -endif- }}
+{{ endif }}
     boolean {item.method_name}();
 {{ endfor }}
 }
diff --git a/tools/aconfig/templates/Flags.java.template b/tools/aconfig/templates/Flags.java.template
index 012eba6660..7f047001d2 100644
--- a/tools/aconfig/templates/Flags.java.template
+++ b/tools/aconfig/templates/Flags.java.template
@@ -5,6 +5,13 @@ public final class Flags \{
     public static final String FLAG_{item.flag_name_constant_suffix} = "{item.device_config_flag}";
 {{- endfor }}
 {{ for item in class_elements}}
+{{ -if not item.is_read_write }}
+{{ -if item.default_value }}
+    @com.android.aconfig.annotations.AssumeTrueForR8
+{{ -else }}
+    @com.android.aconfig.annotations.AssumeFalseForR8
+{{ -endif- }}
+{{ endif }}
     public static boolean {item.method_name}() \{
         return FEATURE_FLAGS.{item.method_name}();
     }
@@ -17,7 +24,7 @@ public final class Flags \{
     public static void unsetFeatureFlags() \{
         Flags.FEATURE_FLAGS = null;
     }
-{{ endif}}
+{{ endif }}
     private static FeatureFlags FEATURE_FLAGS{{ -if not is_test_mode }} = new FeatureFlagsImpl(){{ -endif- }};
 
 }