From 9f04550d40b2f259adace54b8fc81c9cdee6f96b Mon Sep 17 00:00:00 2001
From: Jordan R Abrahams-Whitehead <ajordanr@google.com>
Date: Sat, 15 Jun 2024 00:11:11 +0000
Subject: [PATCH] [scudo] Add baseline Scudo config for ChromeOS v2

---
 .../lib/scudo/standalone/allocator_config.h   | 51 +++++++++++++++++++
 compiler-rt/lib/scudo/standalone/platform.h   |  6 +++
 2 files changed, 57 insertions(+)

diff --git a/compiler-rt/lib/scudo/standalone/allocator_config.h b/compiler-rt/lib/scudo/standalone/allocator_config.h
index 3c6aa3acb0e4..a2fe943016ef 100644
--- a/compiler-rt/lib/scudo/standalone/allocator_config.h
+++ b/compiler-rt/lib/scudo/standalone/allocator_config.h
@@ -204,6 +204,55 @@ struct AndroidConfig {
   template <typename Config> using SecondaryT = MapAllocator<Config>;
 };
 
+struct ChromeOSConfig {
+  static const bool MaySupportMemoryTagging = false;
+  template <class A>
+  using TSDRegistryT = TSDRegistryExT<A>; // Exclusive
+
+  // TODO: Retune configs with more experimentation.
+  struct Primary {
+    using SizeClassMap = DefaultSizeClassMap;
+#if SCUDO_CAN_USE_PRIMARY64
+    static const uptr RegionSizeLog = 29U;
+    static const uptr GroupSizeLog = 20U;
+    typedef uptr CompactPtrT;
+    static const uptr CompactPtrScale = 0;
+    static const bool EnableRandomOffset = true;
+    static const uptr MapSizeIncrement = 1UL << 18;
+#else
+    static const uptr RegionSizeLog = 19U;
+    static const uptr GroupSizeLog = 19U;
+    typedef uptr CompactPtrT;
+#endif
+    static const s32 MinReleaseToOsIntervalMs = INT32_MIN;
+    static const s32 MaxReleaseToOsIntervalMs = INT32_MAX;
+  };
+
+#if SCUDO_CAN_USE_PRIMARY64
+  template <typename Config>
+  using PrimaryT = SizeClassAllocator64<Config>;
+#else
+  template <typename Config>
+  using PrimaryT = SizeClassAllocator32<Config>;
+#endif
+
+  struct Secondary {
+    struct Cache {
+      static const u32 EntriesArraySize = 32U;
+      static const u32 QuarantineSize = 0U;
+      static const u32 DefaultMaxEntriesCount = 32U;
+      static const uptr DefaultMaxEntrySize = 1UL << 19;
+      static const s32 MinReleaseToOsIntervalMs = INT32_MIN;
+      static const s32 MaxReleaseToOsIntervalMs = INT32_MAX;
+    };
+    template <typename Config>
+    using CacheT = MapAllocatorCache<Config>;
+  };
+
+  template <typename Config>
+  using SecondaryT = MapAllocator<Config>;
+};
+
 #if SCUDO_CAN_USE_PRIMARY64
 struct FuchsiaConfig {
   static const bool MaySupportMemoryTagging = false;
@@ -265,6 +314,8 @@ struct TrustyConfig {
 
 #if SCUDO_ANDROID
 typedef AndroidConfig Config;
+#elif SCUDO_CHROMEOS
+typedef ChromeOSConfig Config;
 #elif SCUDO_FUCHSIA
 typedef FuchsiaConfig Config;
 #elif SCUDO_TRUSTY
diff --git a/compiler-rt/lib/scudo/standalone/platform.h b/compiler-rt/lib/scudo/standalone/platform.h
index b71a86be7669..b8b0287ef0b1 100644
--- a/compiler-rt/lib/scudo/standalone/platform.h
+++ b/compiler-rt/lib/scudo/standalone/platform.h
@@ -25,6 +25,12 @@
 #define SCUDO_ANDROID 0
 #endif
 
+#if defined(USE_CHROMEOS_CONFIG)
+#define SCUDO_CHROMEOS 1
+#else
+#define SCUDO_CHROMEOS 0
+#endif
+
 #if defined(__Fuchsia__)
 #define SCUDO_FUCHSIA 1
 #else
-- 
2.45.2.627.g7a2c4fd464-goog