Merge pull request #58529 from eeckstein/enable-cmo-flag

Add a flag `-enable-default-cmo` to enable default cross-module-optimization.

Author: eeckstein

include/swift/AST/SILOptions.h

@@ -66,6 +66,12 @@ enum class DestroyHoistingOption : uint8_t {
   On = 1
 };
 
+enum class CrossModuleOptimizationMode : uint8_t {
+  Off = 0,
+  Default = 1,
+  Aggressive = 2
+};
+
 class SILModule;
 
 class SILOptions {
@@ -117,7 +123,7 @@ class SILOptions {
   bool DisableSILPerfOptimizations = false;
 
   /// Controls whether cross module optimization is enabled.
-  bool CrossModuleOptimization = false;
+  CrossModuleOptimizationMode CMOMode = CrossModuleOptimizationMode::Off;
 
   /// Enables experimental performance annotations.
   bool EnablePerformanceAnnotations = false;

include/swift/AST/TBDGenRequests.h

@@ -50,13 +50,8 @@ class TBDGenDescriptor final {
   FileOrModule Input;
   TBDGenOptions Opts;
 
-  /// Symbols (e.g. function names) which are made public by the
-  /// CrossModuleOptimization pass and therefore must be included in the TBD file.
-  TBDSymbolSetPtr publicCMOSymbols;
-
-  TBDGenDescriptor(FileOrModule input, const TBDGenOptions &opts,
-                   TBDSymbolSetPtr publicCMOSymbols)
-      : Input(input), Opts(opts), publicCMOSymbols(publicCMOSymbols) {
+  TBDGenDescriptor(FileOrModule input, const TBDGenOptions &opts)
+      : Input(input), Opts(opts) {
     assert(input);
   }
 
@@ -78,21 +73,17 @@ class TBDGenDescriptor final {
   const StringRef getDataLayoutString() const;
   const llvm::Triple &getTarget() const;
 
-  TBDSymbolSetPtr getPublicCMOSymbols() const { return publicCMOSymbols; }
-
   bool operator==(const TBDGenDescriptor &other) const;
   bool operator!=(const TBDGenDescriptor &other) const {
     return !(*this == other);
   }
 
-  static TBDGenDescriptor forFile(FileUnit *file, const TBDGenOptions &opts,
-                                  TBDSymbolSetPtr publicCMOSymbols) {
-    return TBDGenDescriptor(file, opts, publicCMOSymbols);
+  static TBDGenDescriptor forFile(FileUnit *file, const TBDGenOptions &opts) {
+    return TBDGenDescriptor(file, opts);
   }
 
-  static TBDGenDescriptor forModule(ModuleDecl *M, const TBDGenOptions &opts,
-                                    TBDSymbolSetPtr publicCMOSymbols) {
-    return TBDGenDescriptor(M, opts, publicCMOSymbols);
+  static TBDGenDescriptor forModule(ModuleDecl *M, const TBDGenOptions &opts) {
+    return TBDGenDescriptor(M, opts);
   }
 };
 
@@ -163,9 +154,6 @@ class SymbolSource {
     /// A symbol used to customize linker behavior, introduced by TBDGen.
     LinkerDirective,
 
-    /// A symbol which was made public by the CrossModuleOptimization pass.
-    CrossModuleOptimization,
-
     /// A symbol with an unknown origin.
     // FIXME: This should be eliminated.
     Unknown
@@ -185,8 +173,7 @@ class SymbolSource {
     irEntity = entity;
   }
   explicit SymbolSource(Kind kind) : kind(kind) {
-    assert(kind == Kind::LinkerDirective || kind == Kind::Unknown ||
-           kind == Kind::CrossModuleOptimization);
+    assert(kind == Kind::LinkerDirective || kind == Kind::Unknown);
   }
 
 public:
@@ -199,9 +186,6 @@ class SymbolSource {
   static SymbolSource forLinkerDirective() {
     return SymbolSource{Kind::LinkerDirective};
   }
-  static SymbolSource forCrossModuleOptimization() {
-    return SymbolSource{Kind::CrossModuleOptimization};
-  }
   static SymbolSource forUnknown() {
     return SymbolSource{Kind::Unknown};
   }
@@ -210,10 +194,6 @@ class SymbolSource {
     return kind == Kind::LinkerDirective;
   }
 
-  bool isFromCrossModuleOptimization() const {
-    return kind == Kind::CrossModuleOptimization;
-  }
-
   SILDeclRef getSILDeclRef() const {
     assert(kind == Kind::SIL);
     return silDeclRef;

include/swift/Frontend/Frontend.h

@@ -436,7 +436,6 @@ class CompilerInstance {
   std::unique_ptr<ASTContext> Context;
   std::unique_ptr<Lowering::TypeConverter> TheSILTypes;
   std::unique_ptr<DiagnosticVerifier> DiagVerifier;
-  TBDSymbolSetPtr publicCMOSymbols;
 
   /// A cache describing the set of inter-module dependencies that have been queried.
   /// Null if not present.
@@ -588,10 +587,6 @@ class CompilerInstance {
   /// file.
   SourceFile *getCodeCompletionFile() const;
 
-  /// Return the symbols (e.g. function names) which are made public by the
-  /// CrossModuleOptimization pass and therefore must be included in the TBD file.
-  TBDSymbolSetPtr getPublicCMOSymbols() const { return publicCMOSymbols; }
-
 private:
   /// Set up the file system by loading and validating all VFS overlay YAML
   /// files. If the process of validating VFS files failed, or the overlay

include/swift/Option/Options.td

@@ -812,6 +812,10 @@ def Oplayground : Flag<["-"], "Oplayground">, Group<O_Group>,
   Flags<[HelpHidden, FrontendOption, ModuleInterfaceOption]>,
   HelpText<"Compile with optimizations appropriate for a playground">;
 
+def EnbaleDefaultCMO : Flag<["-"], "enable-default-cmo">,
+  Flags<[HelpHidden, FrontendOption]>,
+  HelpText<"Perform conservative cross-module optimization">;
+
 def CrossModuleOptimization : Flag<["-"], "cross-module-optimization">,
   Flags<[HelpHidden, FrontendOption]>,
   HelpText<"Perform cross-module optimization">;

include/swift/SIL/SILModule.h

@@ -38,7 +38,6 @@
 #include "swift/SIL/SILVTable.h"
 #include "swift/SIL/SILWitnessTable.h"
 #include "swift/SIL/TypeLowering.h"
-#include "swift/TBDGen/TBDGen.h"
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/FoldingSet.h"
 #include "llvm/ADT/MapVector.h"
@@ -387,10 +386,6 @@ class SILModule {
 
   /// Folding set for key path patterns.
   llvm::FoldingSet<KeyPathPattern> KeyPathPatterns;
-  
-  /// Symbols (e.g. function names) which are made public by the
-  /// CrossModuleOptimization pass and therefore must be included in the TBD file.
-  TBDSymbolSetPtr publicCMOSymbols;
 
 public:
   ~SILModule();
@@ -560,12 +555,6 @@ class SILModule {
 
   const SILOptions &getOptions() const { return Options; }
 
-  /// Return the symbols (e.g. function names) which are made public by the
-  /// CrossModuleOptimization pass and therefore must be included in the TBD file.
-  TBDSymbolSetPtr getPublicCMOSymbols() { return publicCMOSymbols; }
-
-  void addPublicCMOSymbol(StringRef symbol);
-
   using iterator = FunctionListType::iterator;
   using const_iterator = FunctionListType::const_iterator;
   FunctionListType &getFunctionList() { return functions; }

include/swift/TBDGen/TBDGen.h

@@ -16,9 +16,6 @@
 #include "llvm/ADT/StringSet.h"
 #include "swift/Basic/Version.h"
 #include <vector>
-#include <set>
-#include <string>
-#include <memory>
 
 namespace llvm {
 class raw_ostream;
@@ -107,26 +104,12 @@ struct TBDGenOptions {
   }
 };
 
-/// Used for symbols which are made public by the CrossModuleOptimization pass
-/// and therefore must be included in the TBD file.
-///
-/// We cannot use llvm::StringSet, because we need deterministic iteration order.
-using TBDSymbolSet = std::set<std::string>;
-
-/// A pointer to TBDSymbolSet.
-///
-/// Do reference counting for memory management.
-/// This set is created in the optimizer and primarily stored in the SILModule.
-/// But then they need to be kept alive beyond the lifetime of the SILModule.
-using TBDSymbolSetPtr = std::shared_ptr<TBDSymbolSet>;
-
 std::vector<std::string> getPublicSymbols(TBDGenDescriptor desc);
 
 void writeTBDFile(ModuleDecl *M, llvm::raw_ostream &os,
-                  const TBDGenOptions &opts, TBDSymbolSetPtr publicCMOSymbols);
+                  const TBDGenOptions &opts);
 
-void writeAPIJSONFile(ModuleDecl *M, llvm::raw_ostream &os, bool PrettyPrint,
-                      TBDSymbolSetPtr publicCMOSymbols);
+void writeAPIJSONFile(ModuleDecl *M, llvm::raw_ostream &os, bool PrettyPrint);
 
 } // end namespace swift
 

lib/DriverTool/swift_api_extract_main.cpp

@@ -215,7 +215,7 @@ class SwiftAPIExtractInvocation {
       return 1;
 
     if (OutputFilename == "-") {
-      writeAPIJSONFile(M, llvm::outs(), PrettyPrint, nullptr);
+      writeAPIJSONFile(M, llvm::outs(), PrettyPrint);
       return 0;
     }
 
@@ -227,7 +227,7 @@ class SwiftAPIExtractInvocation {
       return 1;
     }
 
-    writeAPIJSONFile(M, OS, PrettyPrint, nullptr);
+    writeAPIJSONFile(M, OS, PrettyPrint);
     return 0;
   }
 };

lib/Frontend/CompilerInvocation.cpp

@@ -1745,7 +1745,11 @@ static bool ParseSILArgs(SILOptions &Opts, ArgList &Args,
       OPT_enable_actor_data_race_checks,
       OPT_disable_actor_data_race_checks, /*default=*/false);
   Opts.DisableSILPerfOptimizations |= Args.hasArg(OPT_disable_sil_perf_optzns);
-  Opts.CrossModuleOptimization |= Args.hasArg(OPT_CrossModuleOptimization);
+  if (Args.hasArg(OPT_CrossModuleOptimization)) {
+    Opts.CMOMode = CrossModuleOptimizationMode::Aggressive;
+  } else if (Args.hasArg(OPT_EnbaleDefaultCMO)) {
+    Opts.CMOMode = CrossModuleOptimizationMode::Default;  
+  }
   Opts.EnablePerformanceAnnotations |=
       Args.hasArg(OPT_ExperimentalPerformanceAnnotations);
   Opts.VerifyAll |= Args.hasArg(OPT_sil_verify_all);

lib/Frontend/Frontend.cpp

@@ -1330,8 +1330,6 @@ bool CompilerInstance::performSILProcessing(SILModule *silModule) {
 
   performSILOptimizations(Invocation, silModule);
 
-  publicCMOSymbols = silModule->getPublicCMOSymbols();
-
   if (auto *stats = getStatsReporter())
     countStatsPostSILOpt(*stats, *silModule);
 

lib/FrontendTool/FrontendTool.cpp

@@ -702,10 +702,16 @@ static bool writeTBDIfNeeded(CompilerInstance &Instance) {
     return false;
   }
 
+  if (Invocation.getSILOptions().CMOMode ==
+      CrossModuleOptimizationMode::Aggressive) {
+    Instance.getDiags().diagnose(SourceLoc(),
+                                 diag::tbd_not_supported_with_cmo);
+    return false;
+  }
+
   const std::string &TBDPath = Invocation.getTBDPathForWholeModule();
 
-  return writeTBD(Instance.getMainModule(), TBDPath, tbdOpts,
-                  Instance.getPublicCMOSymbols());
+  return writeTBD(Instance.getMainModule(), TBDPath, tbdOpts);
 }
 
 static bool performCompileStepsPostSILGen(CompilerInstance &Instance,
@@ -1392,19 +1398,19 @@ static bool processCommandLineAndRunImmediately(CompilerInstance &Instance,
 
 static bool validateTBDIfNeeded(const CompilerInvocation &Invocation,
                                 ModuleOrSourceFile MSF,
-                                const llvm::Module &IRModule,
-                                TBDSymbolSetPtr publicCMOSymbols) {
-  auto mode = Invocation.getFrontendOptions().ValidateTBDAgainstIR;
-  if (mode == FrontendOptions::TBDValidationMode::All &&
-      Invocation.getSILOptions().CrossModuleOptimization)
-    mode = FrontendOptions::TBDValidationMode::MissingFromTBD;
-
+                                const llvm::Module &IRModule) {
+  const auto mode = Invocation.getFrontendOptions().ValidateTBDAgainstIR;
   const bool canPerformTBDValidation = [&]() {
     // If the user has requested we skip validation, honor it.
     if (mode == FrontendOptions::TBDValidationMode::None) {
       return false;
     }
 
+    // Cross-module optimization does not support TBD.
+    if (Invocation.getSILOptions().CMOMode == CrossModuleOptimizationMode::Aggressive) {
+      return false;
+    }
+
     // If we can't validate the given input file, bail early. This covers cases
     // like passing raw SIL as a primary file.
     const auto &IO = Invocation.getFrontendOptions().InputsAndOutputs;
@@ -1465,10 +1471,9 @@ static bool validateTBDIfNeeded(const CompilerInvocation &Invocation,
   // noise from e.g. statically-linked libraries.
   Opts.embedSymbolsFromModules.clear();
   if (auto *SF = MSF.dyn_cast<SourceFile *>()) {
-    return validateTBD(SF, IRModule, Opts, publicCMOSymbols,
-                       diagnoseExtraSymbolsInTBD);
+    return validateTBD(SF, IRModule, Opts, diagnoseExtraSymbolsInTBD);
   } else {
-    return validateTBD(MSF.get<ModuleDecl *>(), IRModule, Opts, publicCMOSymbols,
+    return validateTBD(MSF.get<ModuleDecl *>(), IRModule, Opts,
                        diagnoseExtraSymbolsInTBD);
   }
 }
@@ -1681,8 +1686,6 @@ static bool performCompileStepsPostSILGen(CompilerInstance &Instance,
     return processCommandLineAndRunImmediately(
         Instance, std::move(SM), MSF, observer, ReturnValue);
 
-  TBDSymbolSetPtr publicCMOSymbols = SM->getPublicCMOSymbols();
-
   StringRef OutputFilename = PSPs.OutputFilename;
   std::vector<std::string> ParallelOutputFilenames =
       opts.InputsAndOutputs.copyOutputFilenames();
@@ -1701,8 +1704,7 @@ static bool performCompileStepsPostSILGen(CompilerInstance &Instance,
   if (!IRModule)
     return Instance.getDiags().hadAnyError();
 
-  if (validateTBDIfNeeded(Invocation, MSF, *IRModule.getModule(),
-                          publicCMOSymbols))
+  if (validateTBDIfNeeded(Invocation, MSF, *IRModule.getModule()))
     return true;
 
   return generateCode(Instance, OutputFilename, IRModule.getModule(),