Support Swift CompileJob Caching

Add swift-driver support for compiler caching.

Sources/CSwiftScan/include/swiftscan_header.h

@@ -18,7 +18,7 @@
 #include <stdint.h>
 
 #define SWIFTSCAN_VERSION_MAJOR 0
-#define SWIFTSCAN_VERSION_MINOR 1
+#define SWIFTSCAN_VERSION_MINOR 4
 
 //=== Public Scanner Data Types -------------------------------------------===//
 
@@ -77,6 +77,18 @@ typedef struct {
 typedef struct swiftscan_scan_invocation_s *swiftscan_scan_invocation_t;
 typedef void *swiftscan_scanner_t;
 
+//=== CAS/Caching Specification -------------------------------------------===//
+typedef struct swiftscan_cas_s *swiftscan_cas_t;
+
+typedef enum {
+ SWIFTSCAN_OUTPUT_TYPE_OBJECT = 0,
+ SWIFTSCAN_OUTPUT_TYPE_SWIFTMODULE = 1,
+ SWIFTSCAN_OUTPUT_TYPE_SWIFTINTERFACE = 2,
+ SWIFTSCAN_OUTPUT_TYPE_SWIFTPRIVATEINTERFACE = 3,
+ SWIFTSCAN_OUTPUT_TYPE_CLANG_MODULE = 4,
+ SWIFTSCAN_OUTPUT_TYPE_CLANG_PCH = 5
+} swiftscan_output_kind_t;
+
 //=== libSwiftScan Functions ------------------------------------------------===//
 
 typedef struct {
@@ -117,13 +129,17 @@ typedef struct {
  swiftscan_string_set_t *
  (*swiftscan_swift_textual_detail_get_command_line)(swiftscan_module_details_t);
  swiftscan_string_set_t *
+ (*swiftscan_swift_textual_detail_get_bridging_pch_command_line)(swiftscan_module_details_t);
+ swiftscan_string_set_t *
  (*swiftscan_swift_textual_detail_get_extra_pcm_args)(swiftscan_module_details_t);
  swiftscan_string_ref_t
  (*swiftscan_swift_textual_detail_get_context_hash)(swiftscan_module_details_t);
  bool
  (*swiftscan_swift_textual_detail_get_is_framework)(swiftscan_module_details_t);
  swiftscan_string_set_t *
  (*swiftscan_swift_textual_detail_get_swift_overlay_dependencies)(swiftscan_module_details_t);
+ swiftscan_string_ref_t
+ (*swiftscan_swift_textual_detail_get_module_cache_key)(swiftscan_module_details_t);
 
  //=== Swift Binary Module Details query APIs ------------------------------===//
  swiftscan_string_ref_t
@@ -136,6 +152,8 @@ typedef struct {
  (*swiftscan_swift_binary_detail_get_header_dependencies)(swiftscan_module_details_t);
  bool
  (*swiftscan_swift_binary_detail_get_is_framework)(swiftscan_module_details_t);
+ swiftscan_string_ref_t
+ (*swiftscan_swift_binary_detail_get_module_cache_key)(swiftscan_module_details_t);
 
  //=== Swift Placeholder Module Details query APIs -------------------------===//
  swiftscan_string_ref_t
@@ -154,6 +172,8 @@ typedef struct {
  (*swiftscan_clang_detail_get_command_line)(swiftscan_module_details_t);
  swiftscan_string_set_t *
  (*swiftscan_clang_detail_get_captured_pcm_args)(swiftscan_module_details_t);
+ swiftscan_string_ref_t
+ (*swiftscan_clang_detail_get_module_cache_key)(swiftscan_module_details_t);
 
  //=== Batch Scan Input Functions ------------------------------------------===//
  swiftscan_batch_scan_input_t *
@@ -253,6 +273,17 @@ typedef struct {
  bool (*swiftscan_scanner_cache_load)(swiftscan_scanner_t scanner, const char * path);
  void (*swiftscan_scanner_cache_reset)(swiftscan_scanner_t scanner);
 
+ //=== Scanner CAS Operations ----------------------------------------------===//
+ swiftscan_cas_t (*swiftscan_cas_create)(const char *path);
+ void (*swiftscan_cas_dispose)(swiftscan_cas_t cas);
+ swiftscan_string_ref_t (*swiftscan_cas_store)(swiftscan_cas_t cas,
+ uint8_t *data, unsigned size);
+ swiftscan_string_ref_t (*swiftscan_compute_cache_key)(swiftscan_cas_t cas,
+ int argc,
+ const char *argv,
+ const char *input,
+ swiftscan_output_kind_t);
+
 } swiftscan_functions_t;
 
 #endif // SWIFT_C_DEPENDENCY_SCAN_H

Sources/SwiftDriver/Driver/Driver.swift

@@ -204,6 +204,9 @@ public struct Driver {
  /// The working directory for the driver, if there is one.
  let workingDirectory: AbsolutePath?
 
+ /// CacheKey for bridging header
+ var bridgingHeaderCacheKey: String? = nil
+
  /// The set of input files
  @_spi(Testing) public let inputFiles: [TypedVirtualPath]
 
@@ -263,6 +266,11 @@ public struct Driver {
  /// Whether to consider incremental compilation.
  let shouldAttemptIncrementalCompilation: Bool
 
+ /// CAS/Caching related options.
+ let enableCaching: Bool
+ let useClangIncludeTree: Bool
+ let casPath: String
+
  /// Code & data for incremental compilation. Nil if not running in incremental mode.
  /// Set during planning because needs the jobs to look at outputs.
  @_spi(Testing) public private(set) var incrementalCompilationState: IncrementalCompilationState? = nil
@@ -571,6 +579,17 @@ public struct Driver {
  diagnosticEngine: diagnosticsEngine,
  compilerMode: compilerMode)
 
+ let cachingEnableOverride = parsedOptions.hasArgument(.driverExplicitModuleBuild) && env.keys.contains("SWIFT_ENABLE_CACHING")
+ self.enableCaching = parsedOptions.hasArgument(.cacheCompileJob) || cachingEnableOverride
+ self.useClangIncludeTree = enableCaching && env.keys.contains("SWIFT_CACHING_USE_INCLUDE_TREE")
+ if let casPathOpt = parsedOptions.getLastArgument(.casPath)?.asSingle {
+ self.casPath = casPathOpt.description
+ } else if let cacheEnv = env["CCHROOT"] {
+ self.casPath = cacheEnv
+ } else {
+ self.casPath = ""
+ }
+
  // Compute the working directory.
  workingDirectory = try parsedOptions.getLastArgument(.workingDirectory).map { workingDirectoryArg in
  let cwd = fileSystem.currentWorkingDirectory

Sources/SwiftDriver/ExplicitModuleBuilds/ExplicitDependencyBuildPlanner.swift

@@ -45,6 +45,8 @@ public typealias ExternalTargetModuleDetailsMap = [ModuleDependencyId: ExternalT
  /// Whether we are using the integrated driver via libSwiftDriver shared lib
  private let integratedDriver: Bool
  private let mainModuleName: String?
+ private let enableCAS: Bool
+ private let swiftScanOracle: InterModuleDependencyOracle
 
  /// Clang PCM names contain a hash of the command-line arguments that were used to build them.
  /// We avoid re-running the hash computation with the use of this cache
@@ -55,14 +57,18 @@ public typealias ExternalTargetModuleDetailsMap = [ModuleDependencyId: ExternalT
 
  public init(dependencyGraph: InterModuleDependencyGraph,
  toolchain: Toolchain,
+ dependencyOracle: InterModuleDependencyOracle,
  integratedDriver: Bool = true,
- supportsExplicitInterfaceBuild: Bool = false) throws {
+ supportsExplicitInterfaceBuild: Bool = false,
+ enableCAS: Bool = false) throws {
  self.dependencyGraph = dependencyGraph
  self.toolchain = toolchain
+ self.swiftScanOracle = dependencyOracle
  self.integratedDriver = integratedDriver
  self.mainModuleName = dependencyGraph.mainModuleName
  self.reachabilityMap = try dependencyGraph.computeTransitiveClosure()
  self.supportsExplicitInterfaceBuild = supportsExplicitInterfaceBuild
+ self.enableCAS = enableCAS
  }
 
  /// Generate build jobs for all dependencies of the main module.
@@ -136,7 +142,8 @@ public typealias ExternalTargetModuleDetailsMap = [ModuleDependencyId: ExternalT
  // Resolve all dependency module inputs for this Swift module
  try resolveExplicitModuleDependencies(moduleId: moduleId,
  inputs: &inputs,
- commandLine: &commandLine)
+ commandLine: &commandLine,
+ isMainModule: false)
 
  // Build the .swiftinterfaces file using a list of command line options specified in the
  // `details` field.
@@ -192,7 +199,8 @@ public typealias ExternalTargetModuleDetailsMap = [ModuleDependencyId: ExternalT
 
  // Resolve all dependency module inputs for this Clang module
  try resolveExplicitModuleDependencies(moduleId: moduleId, inputs: &inputs,
- commandLine: &commandLine)
+ commandLine: &commandLine,
+ isMainModule: false)
 
  let moduleMapPath = moduleDetails.moduleMapPath.path
  let modulePCMPath = moduleInfo.modulePath
@@ -221,7 +229,8 @@ public typealias ExternalTargetModuleDetailsMap = [ModuleDependencyId: ExternalT
  /// to use explicitly-built module dependencies.
  private mutating func resolveExplicitModuleDependencies(moduleId: ModuleDependencyId,
  inputs: inout [TypedVirtualPath],
- commandLine: inout [Job.ArgTemplate]) throws {
+ commandLine: inout [Job.ArgTemplate],
+ isMainModule: Bool) throws {
  // Prohibit the frontend from implicitly building textual modules into binary modules.
  var swiftDependencyArtifacts: [SwiftModuleArtifactInfo] = []
  var clangDependencyArtifacts: [ClangModuleArtifactInfo] = []
@@ -256,15 +265,24 @@ public typealias ExternalTargetModuleDetailsMap = [ModuleDependencyId: ExternalT
 
  // Swift Main Module dependencies are passed encoded in a JSON file as described by
  // SwiftModuleArtifactInfo
- if moduleId.moduleName == mainModuleName {
- let dependencyFile =
- try serializeModuleDependencies(for: moduleId,
- swiftDependencyArtifacts: swiftDependencyArtifacts,
- clangDependencyArtifacts: clangDependencyArtifacts)
- commandLine.appendFlag("-explicit-swift-module-map-file")
- commandLine.appendPath(dependencyFile)
- inputs.append(TypedVirtualPath(file: dependencyFile.intern(),
- type: .jsonSwiftArtifacts))
+ if isMainModule {
+ if enableCAS {
+ let dependencyFile =
+ try serializeModuleDependenciesToCAS(for: moduleId,
+ swiftDependencyArtifacts: swiftDependencyArtifacts,
+ clangDependencyArtifacts: clangDependencyArtifacts)
+ commandLine.appendFlag("-explicit-swift-module-map-file")
+ commandLine.appendFlag(dependencyFile)
+ } else {
+ let dependencyFile =
+ try serializeModuleDependencies(for: moduleId,
+ swiftDependencyArtifacts: swiftDependencyArtifacts,
+ clangDependencyArtifacts: clangDependencyArtifacts)
+ commandLine.appendFlag("-explicit-swift-module-map-file")
+ commandLine.appendPath(dependencyFile)
+ inputs.append(TypedVirtualPath(file: dependencyFile.intern(),
+ type: .jsonSwiftArtifacts))
+ }
  }
  }
 
@@ -280,13 +298,15 @@ public typealias ExternalTargetModuleDetailsMap = [ModuleDependencyId: ExternalT
  let isFramework: Bool
  swiftModulePath = .init(file: dependencyInfo.modulePath.path,
  type: .swiftModule)
- isFramework = try dependencyGraph.swiftModuleDetails(of: dependencyId).isFramework ?? false
+ let swiftModuleDetails = try dependencyGraph.swiftModuleDetails(of: dependencyId)
+ isFramework = swiftModuleDetails.isFramework ?? false
  // Accumulate the required information about this dependency
  // TODO: add .swiftdoc and .swiftsourceinfo for this module.
  swiftDependencyArtifacts.append(
  SwiftModuleArtifactInfo(name: dependencyId.moduleName,
  modulePath: TextualVirtualPath(path: swiftModulePath.fileHandle),
- isFramework: isFramework))
+ isFramework: isFramework,
+ moduleCacheKey: swiftModuleDetails.moduleCacheKey))
  case .clang:
  let dependencyInfo = try dependencyGraph.moduleInfo(of: dependencyId)
  let dependencyClangModuleDetails =
@@ -295,7 +315,8 @@ public typealias ExternalTargetModuleDetailsMap = [ModuleDependencyId: ExternalT
  clangDependencyArtifacts.append(
  ClangModuleArtifactInfo(name: dependencyId.moduleName,
  modulePath: TextualVirtualPath(path: dependencyInfo.modulePath.path),
- moduleMapPath: dependencyClangModuleDetails.moduleMapPath))
+ moduleMapPath: dependencyClangModuleDetails.moduleMapPath,
+ moduleCacheKey: dependencyClangModuleDetails.moduleCacheKey))
  case .swiftPrebuiltExternal:
  let prebuiltModuleDetails = try dependencyGraph.swiftPrebuiltDetails(of: dependencyId)
  let compiledModulePath = prebuiltModuleDetails.compiledModulePath
@@ -308,7 +329,8 @@ public typealias ExternalTargetModuleDetailsMap = [ModuleDependencyId: ExternalT
  SwiftModuleArtifactInfo(name: dependencyId.moduleName,
  modulePath: TextualVirtualPath(path: swiftModulePath.fileHandle),
  headerDependencies: prebuiltModuleDetails.headerDependencyPaths,
- isFramework: isFramework))
+ isFramework: isFramework,
+ moduleCacheKey: prebuiltModuleDetails.moduleCacheKey))
  case .swiftPlaceholder:
  fatalError("Unresolved placeholder dependencies at planning stage: \(dependencyId) of \(moduleId)")
  }
@@ -354,24 +376,25 @@ public typealias ExternalTargetModuleDetailsMap = [ModuleDependencyId: ExternalT
  public mutating func resolveMainModuleDependencies(inputs: inout [TypedVirtualPath],
  commandLine: inout [Job.ArgTemplate]) throws {
  let mainModuleId: ModuleDependencyId = .swift(dependencyGraph.mainModuleName)
+
+ let mainModuleDetails = try dependencyGraph.swiftModuleDetails(of: mainModuleId)
+ if let additionalArgs = mainModuleDetails.commandLine {
+ additionalArgs.forEach { commandLine.appendFlag($0) }
+ }
  commandLine.appendFlags("-disable-implicit-swift-modules",
  "-Xcc", "-fno-implicit-modules",
  "-Xcc", "-fno-implicit-module-maps")
  try resolveExplicitModuleDependencies(moduleId: mainModuleId,
  inputs: &inputs,
- commandLine: &commandLine)
+ commandLine: &commandLine,
+ isMainModule: true)
  }
 
  /// Resolve all module dependencies of the main module and add them to the lists of
  /// inputs and command line flags.
  public mutating func resolveBridgingHeaderDependencies(inputs: inout [TypedVirtualPath],
  commandLine: inout [Job.ArgTemplate]) throws {
  let mainModuleId: ModuleDependencyId = .swift(dependencyGraph.mainModuleName)
- // Prohibit the frontend from implicitly building textual modules into binary modules.
- commandLine.appendFlags("-disable-implicit-swift-modules",
- "-Xcc", "-fno-implicit-modules",
- "-Xcc", "-fno-implicit-module-maps")
-
  var swiftDependencyArtifacts: [SwiftModuleArtifactInfo] = []
  var clangDependencyArtifacts: [ClangModuleArtifactInfo] = []
  let mainModuleDetails = try dependencyGraph.swiftModuleDetails(of: mainModuleId)
@@ -409,14 +432,34 @@ public typealias ExternalTargetModuleDetailsMap = [ModuleDependencyId: ExternalT
  inputs.append(clangModuleMapPath)
  }
 
- let dependencyFile =
- try serializeModuleDependencies(for: mainModuleId,
- swiftDependencyArtifacts: swiftDependencyArtifacts,
- clangDependencyArtifacts: clangDependencyArtifacts)
- commandLine.appendFlag("-explicit-swift-module-map-file")
- commandLine.appendPath(dependencyFile)
- inputs.append(TypedVirtualPath(file: dependencyFile.intern(),
- type: .jsonSwiftArtifacts))
+ // Return if depscanner provided build commands.
+ if enableCAS, let scannerPCHArgs = mainModuleDetails.bridgingPchCommandLine {
+ scannerPCHArgs.forEach { commandLine.appendFlag($0) }
+ return
+ }
+
+ // Prohibit the frontend from implicitly building textual modules into binary modules.
+ commandLine.appendFlags("-disable-implicit-swift-modules",
+ "-Xcc", "-fno-implicit-modules",
+ "-Xcc", "-fno-implicit-module-maps")
+
+ if enableCAS {
+ let dependencyFile =
+ try serializeModuleDependenciesToCAS(for: mainModuleId,
+ swiftDependencyArtifacts: swiftDependencyArtifacts,
+ clangDependencyArtifacts: clangDependencyArtifacts)
+ commandLine.appendFlag("-explicit-swift-module-map-file")
+ commandLine.appendFlag(dependencyFile)
+ } else {
+ let dependencyFile =
+ try serializeModuleDependencies(for: mainModuleId,
+ swiftDependencyArtifacts: swiftDependencyArtifacts,
+ clangDependencyArtifacts: clangDependencyArtifacts)
+ commandLine.appendFlag("-explicit-swift-module-map-file")
+ commandLine.appendPath(dependencyFile)
+ inputs.append(TypedVirtualPath(file: dependencyFile.intern(),
+ type: .jsonSwiftArtifacts))
+ }
  }
 
  /// Store the output file artifacts for a given module in a JSON file, return the file's path.
@@ -433,6 +476,22 @@ public typealias ExternalTargetModuleDetailsMap = [ModuleDependencyId: ExternalT
  return VirtualPath.createUniqueTemporaryFileWithKnownContents(.init("\(moduleId.moduleName)-dependencies.json"), contents)
  }
 
+ private func serializeModuleDependenciesToCAS(for moduleId: ModuleDependencyId,
+ swiftDependencyArtifacts: [SwiftModuleArtifactInfo],
+ clangDependencyArtifacts: [ClangModuleArtifactInfo]
+ ) throws -> String {
+ // The module dependency map in CAS needs to be stable.
+ // Sort the dependencies by name.
+ let allDependencyArtifacts: [ModuleDependencyArtifactInfo] =
+ swiftDependencyArtifacts.sorted().map {ModuleDependencyArtifactInfo.swift($0)} +
+ clangDependencyArtifacts.sorted().map {ModuleDependencyArtifactInfo.clang($0)}
+ let encoder = JSONEncoder()
+ // Use sorted key to ensure the order of the keys is stable.
+ encoder.outputFormatting = [.prettyPrinted, .sortedKeys]
+ let contents = try encoder.encode(allDependencyArtifacts)
+ return try swiftScanOracle.store(data: contents)
+ }
+
  private func getPCMHashParts(pcmArgs: [String], contextHash: String) -> [String] {
  var results: [String] = []
  results.append(contextHash)