[CoreCLR] Remove assembly store decompression cache

.github/skills/read-assembly-store/src/AssemblyStore/StoreReader_V2.Classes.cs

@@ -15,18 +15,16 @@ sealed class Header
 
 		// Index size in bytes
 		public readonly uint index_size;
-		public readonly ulong content_id;
 
-		public uint NativeSize => (uint)(5 * sizeof (uint) + ((version & ASSEMBLY_STORE_FORMAT_NUMBER_MASK) >= 4 ? sizeof (ulong) : 0));
+		public const uint NativeSize = 5 * sizeof (uint);
 
-		public Header (uint magic, uint version, uint entry_count, uint index_entry_count, uint index_size, ulong content_id)
+		public Header (uint magic, uint version, uint entry_count, uint index_entry_count, uint index_size)
 		{
 			this.magic = magic;
 			this.version = version;
 			this.entry_count = entry_count;
 			this.index_entry_count = index_entry_count;
 			this.index_size = index_size;
-			this.content_id = content_id;
 		}
 	}
 

.github/skills/read-assembly-store/src/AssemblyStore/StoreReader_V2.cs

@@ -15,10 +15,7 @@ partial class StoreReader_V2 : AssemblyStoreReader
 	const uint ASSEMBLY_STORE_FORMAT_VERSION_32BIT_V2 = 0x00000002;
 	const uint ASSEMBLY_STORE_FORMAT_VERSION_64BIT_V3 = 0x80000003; // Must match the ASSEMBLY_STORE_FORMAT_VERSION native constant
 	const uint ASSEMBLY_STORE_FORMAT_VERSION_32BIT_V3 = 0x00000003;
-	const uint ASSEMBLY_STORE_FORMAT_VERSION_CORECLR_64BIT_V4 = 0x80000004; // Must match the ASSEMBLY_STORE_FORMAT_VERSION native constant
-	const uint ASSEMBLY_STORE_FORMAT_VERSION_CORECLR_32BIT_V4 = 0x00000004;
 	const uint ASSEMBLY_STORE_FORMAT_VERSION_MASK  = 0xF0000000;
-	const uint ASSEMBLY_STORE_FORMAT_NUMBER_MASK   = 0x0000FFFF;
 
 	const uint ASSEMBLY_STORE_ABI_AARCH64          = 0x00010000;
 	const uint ASSEMBLY_STORE_ABI_ARM              = 0x00020000;
@@ -90,10 +87,6 @@ public StoreReader_V2 (Stream store, string path)
 			ASSEMBLY_STORE_FORMAT_VERSION_64BIT_V3 | ASSEMBLY_STORE_ABI_X64,
 			ASSEMBLY_STORE_FORMAT_VERSION_32BIT_V3 | ASSEMBLY_STORE_ABI_ARM,
 			ASSEMBLY_STORE_FORMAT_VERSION_32BIT_V3 | ASSEMBLY_STORE_ABI_X86,
-			ASSEMBLY_STORE_FORMAT_VERSION_CORECLR_64BIT_V4 | ASSEMBLY_STORE_ABI_AARCH64,
-			ASSEMBLY_STORE_FORMAT_VERSION_CORECLR_64BIT_V4 | ASSEMBLY_STORE_ABI_X64,
-			ASSEMBLY_STORE_FORMAT_VERSION_CORECLR_32BIT_V4 | ASSEMBLY_STORE_ABI_ARM,
-			ASSEMBLY_STORE_FORMAT_VERSION_CORECLR_32BIT_V4 | ASSEMBLY_STORE_ABI_X86,
 		};
 	}
 
@@ -140,9 +133,8 @@ protected override bool IsSupported ()
 		uint entry_count       = reader.ReadUInt32 ();
 		uint index_entry_count = reader.ReadUInt32 ();
 		uint index_size        = reader.ReadUInt32 ();
-		ulong content_id        = (version & ASSEMBLY_STORE_FORMAT_NUMBER_MASK) >= 4 ? reader.ReadUInt64 () : 0;
 
-		header = new Header (magic, version, entry_count, index_entry_count, index_size, content_id);
+		header = new Header (magic, version, entry_count, index_entry_count, index_size);
 		return true;
 	}
 
@@ -164,7 +156,7 @@ protected override void Prepare ()
 		AssemblyCount = header.entry_count;
 		IndexEntryCount = header.index_entry_count;
 
-		StoreStream.Seek ((long)elfOffset + header.NativeSize, SeekOrigin.Begin);
+		StoreStream.Seek ((long)elfOffset + Header.NativeSize, SeekOrigin.Begin);
 		using var reader = CreateReader ();
 
 		uint indexEntrySize = GetIndexEntrySize ();

Documentation/building/configuration.md

@@ -118,12 +118,6 @@ Overridable MSBuild properties include:
      assemblies placed in the APK will be compressed in `Release` builds. `Debug`
      builds are not affected.
 
-  * `$(AndroidEnableAssemblyStoreDecompressionCache)`: Defaults to `False`. When
-     enabled for a CoreCLR `Release` build, decompressed assemblies are cached in
-     the app's Android code-cache directory and mapped from there on subsequent
-     launches. The cache consumes additional on-device storage and is rebuilt
-     after app or platform updates.
-
 ## Options suitable for local development
 
 ### Native runtime (`src/native`)

Documentation/project-docs/AssemblyStores.md

@@ -107,11 +107,10 @@ and aligned to a byte boundary.
 The header is a fixed-size structure at the beginning of each assembly store file:
 
 - **MAGIC** (`uint32_t`) - Magic value `0x41424158` ("XABA" in little-endian)
-- **FORMAT_VERSION** (`uint32_t`) - Store format version number (includes ABI and 64-bit flags). Version `3` is used by MonoVM applications and version `4` by CoreCLR applications (see [Hash table format](#hash-table-format))
+- **FORMAT_VERSION** (`uint32_t`) - Store format version number (includes ABI and 64-bit flags). Version `3` is used by MonoVM and CoreCLR applications (see [Hash table format](#hash-table-format))
 - **ENTRY_COUNT** (`uint32_t`) - Number of assemblies in the store
 - **INDEX_ENTRY_COUNT** (`uint32_t`) - Number of entries in the index (typically `ENTRY_COUNT * 2`)
 - **INDEX_SIZE** (`uint32_t`) - Index size in bytes
-- **CONTENT_ID** (`uint64_t`) - Deterministic xxHash3 of everything after the header
 
 ## [INDEX]
 
@@ -169,7 +168,6 @@ All kinds of stores share the following header format:
         uint32_t entry_count;
         uint32_t index_entry_count;
         uint32_t index_size; // index size in bytes
-        uint64_t content_id;
     };
 
 Individual fields have the following meanings:
@@ -181,7 +179,6 @@ Individual fields have the following meanings:
    table, see below)
  - `index_entry_count`: number of entries in the index
  - `index_size`: index size in bytes
- - `content_id`: deterministic xxHash3 of the index, descriptors, names, and assembly data
 
 ## Assembly descriptor table
 
@@ -236,7 +233,7 @@ appending it in order to generate the hash for index lookup.
 
 The hashing algorithm depends on the runtime the application targets:
 
- - **CoreCLR** (store format version `4`): the hash is a 32-bit
+ - **CoreCLR** (store format version `3`): the hash is a 32-bit
    [CRC32](https://en.wikipedia.org/wiki/Cyclic_redundancy_check)
    value, used on both 32-bit and 64-bit platforms.
  - **MonoVM** (store format version `3`): the hash is obtained using the
@@ -287,7 +284,6 @@ struct [[gnu::packed]] AssemblyStoreHeader final
     uint32_t entry_count;
     uint32_t index_entry_count;
     uint32_t index_size; // index size in bytes
-    uint64_t content_id;
 };
 ```
 

src/Xamarin.Android.Build.Tasks/Tasks/GenerateNativeApplicationConfigSources.cs

@@ -66,7 +66,6 @@ public class GenerateNativeApplicationConfigSources : AndroidTask
 		/// </summary>
 		public bool EmitLlvmIrComments { get; set; }
 
-		public bool AndroidEnableAssemblyStoreDecompressionCache { get; set; }
 		public string? RuntimeConfigBinFilePath { get; set; }
 		public string ProjectRuntimeConfigFilePath { get; set; } = String.Empty;
 		public string? ProjectRuntimeConfigDevFilePath { get; set; }
@@ -294,7 +293,6 @@ static bool ShouldSkipAssembly (ITaskItem assembly)
 					MarshalMethodsEnabled = EnableMarshalMethods,
 					IgnoreSplitConfigs = ShouldIgnoreSplitConfigs (),
 					HaveAssemblyStore = UseAssemblyStore,
-					AssemblyStoreDecompressionCacheEnabled = AndroidEnableAssemblyStoreDecompressionCache,
 				};
 			} else {
 				appConfigAsmGen = new ApplicationConfigNativeAssemblyGenerator (envBuilder.EnvironmentVariables, envBuilder.SystemProperties, Log) {

src/Xamarin.Android.Build.Tasks/Tests/Xamarin.Android.Build.Tests/Tasks/CreateAssemblyStoreTests.cs

@@ -1,11 +1,8 @@
 #nullable enable
-using System;
 using System.Collections.Generic;
 using System.IO;
-using System.IO.Hashing;
 using System.Linq;
 
-using Microsoft.Build.Framework;
 using Microsoft.Build.Utilities;
 using NUnit.Framework;
 using Xamarin.Android.Tasks;
@@ -16,14 +13,13 @@ namespace Xamarin.Android.Build.Tests.Tasks;
 public class CreateAssemblyStoreTests : BaseTest
 {
 	[Test]
-	public void ContentIdMatchesStoreContents ()
+	public void CoreCLRStoreUsesVersionThreeHeader ()
 	{
-		string testDirectory = Path.Combine (Root, "temp", nameof (ContentIdMatchesStoreContents));
+		string testDirectory = Path.Combine (Root, "temp", nameof (CoreCLRStoreUsesVersionThreeHeader));
 		Directory.CreateDirectory (testDirectory);
 
 		string assemblyPath = Path.Combine (testDirectory, "Example.dll.zst");
-		byte [] assemblyData = [1, 3, 3, 7, 9, 11, 17, 23];
-		File.WriteAllBytes (assemblyPath, assemblyData);
+		File.WriteAllBytes (assemblyPath, [1, 3, 3, 7, 9, 11, 17, 23]);
 
 		var metadata = new Dictionary<string, string> {
 			["Abi"] = "arm64-v8a",
@@ -41,17 +37,16 @@ public void ContentIdMatchesStoreContents ()
 		Assert.IsTrue (task.Execute (), "CreateAssemblyStore should succeed.");
 
 		string storePath = task.AssembliesToAddToArchive.Single ().ItemSpec;
-		byte [] store = File.ReadAllBytes (storePath);
-		using var reader = new BinaryReader (new MemoryStream (store));
+		using var reader = new BinaryReader (File.OpenRead (storePath));
 		Assert.AreEqual (0x41424158u, reader.ReadUInt32 (), "Unexpected assembly store magic.");
-		Assert.AreEqual (0x80010004u, reader.ReadUInt32 (), "Unexpected arm64 assembly store version.");
-		reader.BaseStream.Seek (3 * sizeof (uint), SeekOrigin.Current);
-		ulong contentId = reader.ReadUInt64 ();
-
-		Assert.AreEqual (
-			XxHash3.HashToUInt64 (store.AsSpan (5 * sizeof (uint) + sizeof (ulong))),
-			contentId,
-			"The content ID should hash everything after the assembly store header."
-		);
+		Assert.AreEqual (0x80010003u, reader.ReadUInt32 (), "Unexpected arm64 assembly store version.");
+		uint assemblyCount = reader.ReadUInt32 ();
+		uint indexEntryCount = reader.ReadUInt32 ();
+		Assert.AreEqual (assemblyCount * 2, indexEntryCount, "Unexpected index entry count.");
+		uint indexSize = reader.ReadUInt32 ();
+		Assert.AreEqual (5 * sizeof (uint), reader.BaseStream.Position, "Unexpected assembly store header size.");
+
+		reader.BaseStream.Seek (indexSize, SeekOrigin.Current);
+		Assert.AreEqual (0u, reader.ReadUInt32 (), "The first descriptor should immediately follow the index.");
 	}
 }

src/Xamarin.Android.Build.Tasks/Tests/Xamarin.Android.Build.Tests/Tasks/GenerateNativeApplicationConfigSourcesTests.cs

@@ -42,37 +42,4 @@ public void HaveAssemblyStoreIsEmittedForCoreCLR (bool haveAssemblyStore)
 		var config = (EnvironmentHelper.ApplicationConfig_CoreCLR)EnvironmentHelper.ReadApplicationConfig (environmentFiles, AndroidRuntime.CoreCLR);
 		Assert.AreEqual (haveAssemblyStore, config.have_assembly_store);
 	}
-
-	[TestCase (false)]
-	[TestCase (true)]
-	public void AssemblyStoreDecompressionCacheSettingIsEmitted (bool enabled)
-	{
-		string outputRoot = Path.Combine (Root, "temp", $"{nameof (AssemblyStoreDecompressionCacheSettingIsEmitted)}-{enabled}");
-		string monoAndroidPath = Path.Combine (TestEnvironment.MonoAndroidFrameworkDirectory, "Mono.Android.dll");
-		FileAssert.Exists (monoAndroidPath);
-
-		var task = new GenerateNativeApplicationConfigSources {
-			BuildEngine = new MockBuildEngine (TestContext.Out),
-			ResolvedAssemblies = [new TaskItem (monoAndroidPath)],
-			EnvironmentOutputDirectory = Path.Combine (outputRoot, "android"),
-			SupportedAbis = ["arm64-v8a"],
-			AndroidPackageName = "com.microsoft.android.cachetest",
-			EnablePreloadAssembliesDefault = false,
-			TargetsCLR = true,
-			AndroidRuntime = "CoreCLR",
-			UseAssemblyStore = true,
-			AndroidEnableAssemblyStoreDecompressionCache = enabled,
-		};
-
-		Assert.IsTrue (task.Execute (), "GenerateNativeApplicationConfigSources should succeed.");
-
-		var environmentFiles = EnvironmentHelper.GatherEnvironmentFiles (
-			outputRoot,
-			"arm64-v8a",
-			required: true,
-			runtime: AndroidRuntime.CoreCLR
-		);
-		var config = (EnvironmentHelper.ApplicationConfig_CoreCLR)EnvironmentHelper.ReadApplicationConfig (environmentFiles, AndroidRuntime.CoreCLR);
-		Assert.AreEqual (enabled, config.assembly_store_decompression_cache_enabled);
-	}
 }

src/Xamarin.Android.Build.Tasks/Tests/Xamarin.Android.Build.Tests/Utilities/EnvironmentHelper.cs

@@ -61,10 +61,9 @@ public sealed class ApplicationConfig_CoreCLR : IApplicationConfig
 			public uint   jni_remapping_replacement_method_index_entry_count;
 			public string android_package_name = String.Empty;
 			public bool   have_assembly_store;
-			public bool   assembly_store_decompression_cache_enabled;
 		}
 
-		const uint ApplicationConfigFieldCount_CoreCLR = 20;
+		const uint ApplicationConfigFieldCount_CoreCLR = 19;
 
 		// This must be identical to the ApplicationConfig structure in src/native/mono/xamarin-app-stub/xamarin-app.hh
 		public sealed class ApplicationConfig_MonoVM : IApplicationConfig
@@ -402,10 +401,6 @@ static IApplicationConfig ReadApplicationConfig_CoreCLR (EnvironmentFile envFile
 						ret.have_assembly_store = ConvertFieldToBool ("have_assembly_store", envFile.Path, parser.SourceFilePath, item.LineNumber, field [1]);
 						break;
 
-					case 19: // assembly_store_decompression_cache_enabled: bool / .byte
-						AssertFieldType (envFile.Path, parser.SourceFilePath, ".byte", field [0], item.LineNumber);
-						ret.assembly_store_decompression_cache_enabled = ConvertFieldToBool ("assembly_store_decompression_cache_enabled", envFile.Path, parser.SourceFilePath, item.LineNumber, field [1]);
-						break;
 				}
 				fieldCount++;
 			}
@@ -766,7 +761,6 @@ static void AssertApplicationConfigIsIdentical (ApplicationConfig_CoreCLR firstA
 			Assert.AreEqual (firstAppConfig.system_property_count, secondAppConfig.system_property_count, $"Field 'system_property_count' has different value in environment file '{secondEnvFile}' than in environment file '{firstEnvFile}'");
 			Assert.AreEqual (firstAppConfig.android_package_name, secondAppConfig.android_package_name, $"Field 'android_package_name' has different value in environment file '{secondEnvFile}' than in environment file '{firstEnvFile}'");
 			Assert.AreEqual (firstAppConfig.have_assembly_store, secondAppConfig.have_assembly_store, $"Field 'have_assembly_store' has different value in environment file '{secondEnvFile}' than in environment file '{firstEnvFile}'");
-			Assert.AreEqual (firstAppConfig.assembly_store_decompression_cache_enabled, secondAppConfig.assembly_store_decompression_cache_enabled, $"Field 'assembly_store_decompression_cache_enabled' has different value in environment file '{secondEnvFile}' than in environment file '{firstEnvFile}'");
 		}
 
 		static void AssertApplicationConfigIsIdentical (ApplicationConfig_MonoVM firstAppConfig, string firstEnvFile, ApplicationConfig_MonoVM secondAppConfig, string secondEnvFile)

src/Xamarin.Android.Build.Tasks/Utilities/ApplicationConfigCLR.cs

@@ -50,5 +50,4 @@ sealed class ApplicationConfigCLR
 	public uint   jni_remapping_replacement_method_index_entry_count;
 	public string android_package_name = String.Empty;
 	public bool   have_assembly_store;
-	public bool   assembly_store_decompression_cache_enabled;
 }

src/Xamarin.Android.Build.Tasks/Utilities/ApplicationConfigNativeAssemblyGeneratorCLR.cs

@@ -199,7 +199,6 @@ sealed class DsoCacheState
 	public bool MarshalMethodsEnabled { get; set; }
 	public bool IgnoreSplitConfigs { get; set; }
 	public bool HaveAssemblyStore { get; set; }
-	public bool AssemblyStoreDecompressionCacheEnabled { get; set; }
 
 	public ApplicationConfigNativeAssemblyGeneratorCLR (IDictionary<string, string> environmentVariables, IDictionary<string, string> systemProperties,
 		IDictionary<string, string>? runtimeProperties, TaskLoggingHelper log)
@@ -287,7 +286,6 @@ protected override void Construct (LlvmIrModule module)
 			jni_remapping_replacement_method_index_entry_count = (uint)JniRemappingReplacementMethodIndexEntryCount,
 			android_package_name = AndroidPackageName,
 			have_assembly_store = HaveAssemblyStore,
-			assembly_store_decompression_cache_enabled = AssemblyStoreDecompressionCacheEnabled,
 		};
 		application_config = new StructureInstance<ApplicationConfigCLR> (applicationConfigStructureInfo, app_cfg);
 		module.AddGlobalVariable ("application_config", application_config);

src/Xamarin.Android.Build.Tasks/Utilities/AssemblyStoreGenerator.Classes.cs

@@ -5,7 +5,7 @@ partial class AssemblyStoreGenerator
 {
 	sealed class AssemblyStoreHeader
 	{
-		public const uint NativeSize = 5 * sizeof (uint) + sizeof (ulong);
+		public const uint NativeSize = 5 * sizeof (uint);
 
 		public readonly uint magic = ASSEMBLY_STORE_MAGIC;
 		public readonly uint version;
@@ -14,19 +14,17 @@ sealed class AssemblyStoreHeader
 
 		// Index size in bytes
 		public readonly uint index_size;
-		public readonly ulong content_id;
 
-		public AssemblyStoreHeader (uint version, uint entry_count, uint index_entry_count, uint index_size, ulong content_id)
+		public AssemblyStoreHeader (uint version, uint entry_count, uint index_entry_count, uint index_size)
 		{
 			this.version = version;
 			this.entry_count = entry_count;
 			this.index_entry_count = index_entry_count;
 			this.index_size = index_size;
-			this.content_id = content_id;
 		}
 #if XABT_TESTS
-		public AssemblyStoreHeader (uint magic, uint version, uint entry_count, uint index_entry_count, uint index_size, ulong content_id)
-			: this (version, entry_count, index_entry_count, index_size, content_id)
+		public AssemblyStoreHeader (uint magic, uint version, uint entry_count, uint index_entry_count, uint index_size)
+			: this (version, entry_count, index_entry_count, index_size)
 		{
 			this.magic = magic;
 		}