commit 55112ca58a5a4c9a1c4c91847921b0b2731ba259
author Martin Stjernholm <mast@google.com> Mon Oct 31 23:23:36 2022 +0000
committer Treehugger Robot <treehugger-gerrit@google.com> Tue Nov 01 20:26:44 2022 +0000
tree 11dde7d849965fc69e1f96c14b404a065199e64c
parent f66ea6c4cbc5d44b2c34960488d66f690dd40f8d

Add a phenotype flag to disable compact dex in dex2oat.

The purpose is in particular to control usage of libart-dexlayout.so to
conduct an experiment on its impact.

Add the flag to odrefresh recompile logic since odex files are
invalidated when it changes.

Test: Gtests and run tests on host and in chroot
  with the flag defaulting to true and dexlayout dependencies
  temporarily commented out from dex2oat/linker/oat_writer.cc.
  Intentional failures in compact dex related gtests in
  art_dex2oat_tests:
    Dex2oatTest.LayoutSections
    Dex2oatTest.GenerateCompactDex
    Dex2oatTest.CompactDexInZip
Bug: 256664509
Change-Id: If518f7d128e99eddbd8f643c2d8b8b4a39efaef4

dex2oat/dex2oat.cc

diff --git a/dex2oat/dex2oat.cc b/dex2oat/dex2oat.cc
index d0e22a5..fa15e53 100644
--- a/dex2oat/dex2oat.cc
+++ b/dex2oat/dex2oat.cc
@@ -39,6 +39,7 @@
 #endif
 
 #include "android-base/parseint.h"
+#include "android-base/properties.h"
 #include "android-base/scopeguard.h"
 #include "android-base/stringprintf.h"
 #include "android-base/strings.h"
@@ -1101,6 +1102,19 @@
     AssignIfExists(args, M::PublicSdk, &public_sdk_);
     AssignIfExists(args, M::ApexVersions, &apex_versions_argument_);
 
+    // Check for phenotype flag to override compact_dex_level_, if it isn't "none" already.
+    // TODO(b/256664509): Clean this up.
+    if (compact_dex_level_ != CompactDexLevel::kCompactDexLevelNone) {
+      std::string ph_disable_compact_dex =
+          android::base::GetProperty(kPhDisableCompactDex, "false");
+      if (ph_disable_compact_dex == "true") {
+        LOG(WARNING)
+            << "Overriding --compact-dex-level due to "
+               "persist.device_config.runtime_native_boot.disable_compact_dex set to `true`";
+        compact_dex_level_ = CompactDexLevel::kCompactDexLevelNone;
+      }
+    }
+
     AssignIfExists(args, M::Backend, &compiler_kind_);
     parser_options->requested_specific_compiler = args.Exists(M::Backend);
 

libartbase/base/globals.h

diff --git a/libartbase/base/globals.h b/libartbase/base/globals.h
index 8d37b8a..f4d44b8 100644
--- a/libartbase/base/globals.h
+++ b/libartbase/base/globals.h
@@ -107,6 +107,12 @@
 static constexpr bool kHostStaticBuildEnabled = false;
 #endif
 
+// System property for phenotype flag to test disabling compact dex and in
+// particular dexlayout.
+// TODO(b/256664509): Clean this up.
+static constexpr char kPhDisableCompactDex[] =
+    "persist.device_config.runtime_native_boot.disable_compact_dex";
+
 }  // namespace art
 
 #endif  // ART_LIBARTBASE_BASE_GLOBALS_H_

odrefresh/odr_config.h

diff --git a/odrefresh/odr_config.h b/odrefresh/odr_config.h
index 420f680..5261fe4 100644
--- a/odrefresh/odr_config.h
+++ b/odrefresh/odr_config.h
@@ -67,7 +67,8 @@
 // requirement (go/platform-experiments-flags#pre-requisites).
 const android::base::NoDestructor<std::vector<SystemPropertyConfig>> kSystemProperties{
     {SystemPropertyConfig{.name = "persist.device_config.runtime_native_boot.enable_uffd_gc",
-                          .default_value = "false"}}};
+                          .default_value = "false"},
+     SystemPropertyConfig{.name = kPhDisableCompactDex, .default_value = "false"}}};
 
 // An enumeration of the possible zygote configurations on Android.
 enum class ZygoteKind : uint8_t {