[SILGen] Add flag to skip typechecking and SIL gen for all function bodies

include/swift/AST/Decl.h

@@ -2,7 +2,7 @@
 //
 // This source file is part of the Swift.org open source project
 //
-// Copyright (c) 2014 - 2018 Apple Inc. and the Swift project authors
+// Copyright (c) 2014 - 2020 Apple Inc. and the Swift project authors
 // Licensed under Apache License v2.0 with Runtime Library Exception
 //
 // See https://swift.org/LICENSE.txt for license information
@@ -5659,13 +5659,14 @@ class AbstractFunctionDecl : public GenericContext, public ValueDecl {
   /// Set a new body for the function.
   void setBody(BraceStmt *S, BodyKind NewBodyKind);
 
-  /// Note that the body was skipped for this function.  Function body
+  /// Note that the body was skipped for this function. Function body
   /// cannot be attached after this call.
   void setBodySkipped(SourceRange bodyRange) {
-    // FIXME: Remove 'Parsed' from this once we can delay parsing function
-    //        bodies. Right now -experimental-skip-non-inlinable-function-bodies
-    //        requires being able to change the state from Parsed to Skipped,
-    //        because we're still eagerly parsing function bodies.
+    // FIXME: Remove 'Parsed' from this list once we can always delay
+    //        parsing bodies. The -experimental-skip-*-function-bodies options
+    //        do currently skip parsing, unless disabled through other means in
+    //        SourceFile::hasDelayedBodyParsing (eg. needing to build the full
+    //        syntax tree due to -verify-syntax-tree).
     assert(getBodyKind() == BodyKind::None ||
            getBodyKind() == BodyKind::Unparsed ||
            getBodyKind() == BodyKind::Parsed);

include/swift/AST/DiagnosticsFrontend.def

@@ -2,7 +2,7 @@
 //
 // This source file is part of the Swift.org open source project
 //
-// Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
+// Copyright (c) 2014 - 2020 Apple Inc. and the Swift project authors
 // Licensed under Apache License v2.0 with Runtime Library Exception
 //
 // See https://swift.org/LICENSE.txt for license information
@@ -128,8 +128,7 @@ ERROR(error_mode_cannot_emit_interface,none,
 ERROR(error_mode_cannot_emit_module_summary,none,
       "this mode does not support emitting module summary files", ())
 ERROR(cannot_emit_ir_skipping_function_bodies,none,
-      "-experimental-skip-non-inlinable-function-bodies does not support "
-      "emitting IR", ())
+      "-experimental-skip-*-function-bodies do not support emitting IR", ())
 
 WARNING(emit_reference_dependencies_without_primary_file,none,
   "ignoring -emit-reference-dependencies (requires -primary-file)", ())
@@ -416,7 +415,7 @@ ERROR(expectation_missing_opening_braces,none,
 ERROR(expectation_missing_closing_braces,none,
       "didn't find '}}' to match '{{' in expectation", ())
 
-WARNING(module_incompatible_with_skip_function_bodies,none,
+WARNING(module_incompatible_with_skip_non_inlinable_function_bodies,none,
         "module '%0' cannot be built with "
         "-experimental-skip-non-inlinable-function-bodies; this option has "
         "been automatically disabled", (StringRef))

include/swift/AST/SILOptions.h

@@ -2,7 +2,7 @@
 //
 // This source file is part of the Swift.org open source project
 //
-// Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
+// Copyright (c) 2014 - 2020 Apple Inc. and the Swift project authors
 // Licensed under Apache License v2.0 with Runtime Library Exception
 //
 // See https://swift.org/LICENSE.txt for license information
@@ -18,14 +18,15 @@
 #ifndef SWIFT_AST_SILOPTIONS_H
 #define SWIFT_AST_SILOPTIONS_H
 
-#include "swift/Basic/Sanitizers.h"
-#include "swift/Basic/OptionSet.h"
+#include "swift/Basic/FunctionBodySkipping.h"
 #include "swift/Basic/OptimizationMode.h"
+#include "swift/Basic/OptionSet.h"
+#include "swift/Basic/Sanitizers.h"
 #include "llvm/ADT/Hashing.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Remarks/RemarkFormat.h"
-#include <string>
 #include <climits>
+#include <string>
 
 namespace swift {
 
@@ -88,8 +89,8 @@ class SILOptions {
   /// and go from OSSA to non-ownership SIL.
   bool StopOptimizationBeforeLoweringOwnership = false;
 
-  /// Whether to skip emitting non-inlinable function bodies.
-  bool SkipNonInlinableFunctionBodies = false;
+  // The kind of function bodies to skip emitting.
+  FunctionBodySkipping SkipFunctionBodies = FunctionBodySkipping::None;
 
   /// Optimization mode being used.
   OptimizationMode OptMode = OptimizationMode::NotSet;

include/swift/Basic/FunctionBodySkipping.h

@@ -0,0 +1,33 @@
+//===------------------- FunctionBodySkipping.h -----------------*- C++ -*-===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2014 - 2020 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef SWIFT_BASIC_FUNCTIONBODYSKIPPING_H
+#define SWIFT_BASIC_FUNCTIONBODYSKIPPING_H
+
+#include "llvm/Support/DataTypes.h"
+
+namespace swift {
+
+/// Describes the function bodies that can be skipped in type-checking.
+enum class FunctionBodySkipping : uint8_t {
+  /// Do not skip type-checking for any function bodies.
+  None,
+  /// Only non-inlinable function bodies should be skipped.
+  NonInlinable,
+  /// All function bodies should be skipped, where not otherwise required
+  /// for type inference.
+  All
+};
+
+} // end namespace swift
+
+#endif // SWIFT_BASIC_FUNCTIONBODYSKIPPING_H

include/swift/Basic/LangOptions.h

@@ -2,7 +2,7 @@
 //
 // This source file is part of the Swift.org open source project
 //
-// Copyright (c) 2014 - 2018 Apple Inc. and the Swift project authors
+// Copyright (c) 2014 - 2020 Apple Inc. and the Swift project authors
 // Licensed under Apache License v2.0 with Runtime Library Exception
 //
 // See https://swift.org/LICENSE.txt for license information
@@ -18,18 +18,19 @@
 #ifndef SWIFT_BASIC_LANGOPTIONS_H
 #define SWIFT_BASIC_LANGOPTIONS_H
 
-#include "swift/Config.h"
+#include "swift/Basic/FunctionBodySkipping.h"
 #include "swift/Basic/LLVM.h"
 #include "swift/Basic/Version.h"
+#include "swift/Config.h"
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/Hashing.h"
+#include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringRef.h"
-#include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/Triple.h"
 #include "llvm/Support/Regex.h"
-#include "llvm/Support/raw_ostream.h"
 #include "llvm/Support/VersionTuple.h"
+#include "llvm/Support/raw_ostream.h"
 #include <string>
 #include <vector>
 
@@ -489,9 +490,8 @@ namespace swift {
     /// dumped to llvm::errs().
     bool DebugTimeExpressions = false;
 
-    /// Indicate that the type checker should skip type-checking non-inlinable
-    /// function bodies.
-    bool SkipNonInlinableFunctionBodies = false;
+    /// Controls the function bodies to skip during type-checking.
+    FunctionBodySkipping SkipFunctionBodies = FunctionBodySkipping::None;
 
     ///
     /// Flags for developers

include/swift/Option/FrontendOptions.td

@@ -762,4 +762,9 @@ def use_static_resource_dir
 def disable_building_interface
   : Flag<["-"], "disable-building-interface">,
     HelpText<"Disallow building binary module from textual interface">;
+
+def experimental_skip_all_function_bodies:
+  Flag<["-"], "experimental-skip-all-function-bodies">,
+  HelpText<"Skip type-checking function bodies and all SIL generation">;
+
 } // end let Flags = [FrontendOption, NoDriverOption, HelpHidden]

include/swift/Option/Options.td

@@ -2,7 +2,7 @@
 //
 // This source file is part of the Swift.org open source project
 //
-// Copyright (c) 2014 - 2018 Apple Inc. and the Swift project authors
+// Copyright (c) 2014 - 2020 Apple Inc. and the Swift project authors
 // Licensed under Apache License v2.0 with Runtime Library Exception
 //
 // See https://swift.org/LICENSE.txt for license information

include/swift/SILOptimizer/PassManager/Passes.def

@@ -2,7 +2,7 @@
 //
 // This source file is part of the Swift.org open source project
 //
-// Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
+// Copyright (c) 2014 - 2020 Apple Inc. and the Swift project authors
 // Licensed under Apache License v2.0 with Runtime Library Exception
 //
 // See https://swift.org/LICENSE.txt for license information
@@ -191,6 +191,9 @@ PASS(GenericSpecializer, "generic-specializer",
      "Generic Function Specialization on Static Types")
 PASS(ExistentialSpecializer, "existential-specializer",
      "Existential Specializer")
+PASS(SILSkippingChecker, "check-sil-skipping",
+     "Utility pass to ensure -experimental-skip-*-function-bodies skip "
+     "SIL generation of not-to-be-serialized functions entirely")
 PASS(GlobalOpt, "global-opt",
      "SIL Global Optimization")
 PASS(GlobalPropertyOpt, "global-property-opt",
@@ -345,9 +348,6 @@ PASS(SerializeSILPass, "serialize-sil",
      "Utility pass. Serializes the current SILModule")
 PASS(CMOSerializeSILPass, "cmo-serialize-sil",
      "Utility pass. Serializes the current SILModule for cross-module-optimization")
-PASS(NonInlinableFunctionSkippingChecker, "check-non-inlinable-function-skipping",
-     "Utility pass to ensure -experimental-skip-non-inlinable-function-bodies "
-     "skips everything it should")
 PASS(YieldOnceCheck, "yield-once-check",
     "Check correct usage of yields in yield-once coroutines")
 PASS(OSLogOptimization, "os-log-optimization", "Optimize os log calls")

lib/Frontend/ArgsToFrontendInputsConverter.cpp

@@ -2,7 +2,7 @@
 //
 // This source file is part of the Swift.org open source project
 //
-// Copyright (c) 2014 - 2018 Apple Inc. and the Swift project authors
+// Copyright (c) 2014 - 2020 Apple Inc. and the Swift project authors
 // Licensed under Apache License v2.0 with Runtime Library Exception
 //
 // See https://swift.org/LICENSE.txt for license information

lib/Frontend/ArgsToFrontendOptionsConverter.cpp

@@ -193,8 +193,9 @@ bool ArgsToFrontendOptionsConverter::convert(
   if (checkUnusedSupplementaryOutputPaths())
     return true;
 
-  if (FrontendOptions::doesActionGenerateIR(Opts.RequestedAction)
-      && Args.hasArg(OPT_experimental_skip_non_inlinable_function_bodies)) {
+  if (FrontendOptions::doesActionGenerateIR(Opts.RequestedAction) &&
+      (Args.hasArg(OPT_experimental_skip_non_inlinable_function_bodies) ||
+       Args.hasArg(OPT_experimental_skip_all_function_bodies))) {
     Diags.diagnose(SourceLoc(), diag::cannot_emit_ir_skipping_function_bodies);
     return true;
   }

lib/Frontend/CompilerInvocation.cpp

@@ -2,7 +2,7 @@
 //
 // This source file is part of the Swift.org open source project
 //
-// Copyright (c) 2014 - 2019 Apple Inc. and the Swift project authors
+// Copyright (c) 2014 - 2020 Apple Inc. and the Swift project authors
 // Licensed under Apache License v2.0 with Runtime Library Exception
 //
 // See https://swift.org/LICENSE.txt for license information
@@ -715,22 +715,26 @@ static bool ParseTypeCheckerArgs(TypeCheckerOptions &Opts, ArgList &Args,
   Opts.DebugTimeFunctionBodies |= Args.hasArg(OPT_debug_time_function_bodies);
   Opts.DebugTimeExpressions |=
       Args.hasArg(OPT_debug_time_expression_type_checking);
-  Opts.SkipNonInlinableFunctionBodies |=
-      Args.hasArg(OPT_experimental_skip_non_inlinable_function_bodies);
 
   // If asked to perform InstallAPI, go ahead and enable non-inlinable function
   // body skipping.
-  Opts.SkipNonInlinableFunctionBodies |= Args.hasArg(OPT_tbd_is_installapi);
+  if (Args.hasArg(OPT_experimental_skip_non_inlinable_function_bodies) ||
+      Args.hasArg(OPT_tbd_is_installapi))
+    Opts.SkipFunctionBodies = FunctionBodySkipping::NonInlinable;
 
-  if (Opts.SkipNonInlinableFunctionBodies &&
+  if (Args.hasArg(OPT_experimental_skip_all_function_bodies))
+    Opts.SkipFunctionBodies = FunctionBodySkipping::All;
+
+  if (Opts.SkipFunctionBodies == FunctionBodySkipping::NonInlinable &&
       FrontendOpts.ModuleName == SWIFT_ONONE_SUPPORT) {
     // Disable this optimization if we're compiling SwiftOnoneSupport, because
     // we _definitely_ need to look inside every declaration to figure out
     // what gets prespecialized.
-    Opts.SkipNonInlinableFunctionBodies = false;
-    Diags.diagnose(SourceLoc(),
-                   diag::module_incompatible_with_skip_function_bodies,
-                   SWIFT_ONONE_SUPPORT);
+    Opts.SkipFunctionBodies = FunctionBodySkipping::None;
+    Diags.diagnose(
+        SourceLoc(),
+        diag::module_incompatible_with_skip_non_inlinable_function_bodies,
+        SWIFT_ONONE_SUPPORT);
   }
 
   Opts.DisableConstraintSolverPerformanceHacks |=
@@ -1060,8 +1064,8 @@ static bool ParseSILArgs(SILOptions &Opts, ArgList &Args,
     Opts.StopOptimizationAfterSerialization = true;
 
   // Propagate the typechecker's understanding of
-  // -experimental-skip-non-inlinable-function-bodies to SIL.
-  Opts.SkipNonInlinableFunctionBodies = TCOpts.SkipNonInlinableFunctionBodies;
+  // -experimental-skip-*-function-bodies to SIL.
+  Opts.SkipFunctionBodies = TCOpts.SkipFunctionBodies;
 
   // Parse the optimization level.
   // Default to Onone settings if no option is passed.

lib/Frontend/Frontend.cpp

@@ -2,7 +2,7 @@
 //
 // This source file is part of the Swift.org open source project
 //
-// Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
+// Copyright (c) 2014 - 2020 Apple Inc. and the Swift project authors
 // Licensed under Apache License v2.0 with Runtime Library Exception
 //
 // See https://swift.org/LICENSE.txt for license information
@@ -1039,8 +1039,11 @@ CompilerInstance::getSourceFileParsingOptions(bool forPrimary) const {
   }
 
   if (forPrimary || isWholeModuleCompilation()) {
-    // Disable delayed body parsing for primaries and in WMO.
-    opts |= SourceFile::ParsingFlags::DisableDelayedBodies;
+    // Disable delayed body parsing for primaries and in WMO, unless
+    // forcefully skipping function bodies
+    auto typeOpts = getASTContext().TypeCheckerOpts;
+    if (typeOpts.SkipFunctionBodies == FunctionBodySkipping::None)
+      opts |= SourceFile::ParsingFlags::DisableDelayedBodies;
   } else {
     // Suppress parse warnings for non-primaries, as they'll get parsed multiple
     // times.

lib/SILGen/SILGen.cpp

@@ -2,7 +2,7 @@
 //
 // This source file is part of the Swift.org open source project
 //
-// Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
+// Copyright (c) 2014 - 2020 Apple Inc. and the Swift project authors
 // Licensed under Apache License v2.0 with Runtime Library Exception
 //
 // See https://swift.org/LICENSE.txt for license information
@@ -1946,6 +1946,12 @@ ASTLoweringRequest::evaluate(Evaluator &evaluator,
 
   auto silMod = SILModule::createEmptyModule(desc.context, desc.conv,
                                              desc.opts);
+
+  // If all function bodies are being skipped there's no reason to do any
+  // SIL generation.
+  if (desc.opts.SkipFunctionBodies == FunctionBodySkipping::All)
+    return silMod;
+
   SILGenModuleRAII scope(*silMod);
 
   // Emit a specific set of SILDeclRefs if needed.

lib/SILOptimizer/PassManager/PassPipeline.cpp

@@ -2,7 +2,7 @@
 //
 // This source file is part of the Swift.org open source project
 //
-// Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
+// Copyright (c) 2014 - 2020 Apple Inc. and the Swift project authors
 // Licensed under Apache License v2.0 with Runtime Library Exception
 //
 // See https://swift.org/LICENSE.txt for license information
@@ -116,10 +116,10 @@ static void addMandatoryDiagnosticOptPipeline(SILPassPipelinePlan &P) {
   P.addClosureLifetimeFixup();
 
 #ifndef NDEBUG
-  // Add a verification pass to check our work when skipping non-inlinable
+  // Add a verification pass to check our work when skipping
   // function bodies.
-  if (Options.SkipNonInlinableFunctionBodies)
-    P.addNonInlinableFunctionSkippingChecker();
+  if (Options.SkipFunctionBodies != FunctionBodySkipping::None)
+    P.addSILSkippingChecker();
 #endif
 
   if (Options.shouldOptimize()) {

lib/SILOptimizer/UtilityPasses/CMakeLists.txt

@@ -9,7 +9,6 @@ target_sources(swiftSILOptimizer PRIVATE
   BugReducerTester.cpp
   CFGPrinter.cpp
   CallerAnalysisPrinter.cpp
-  NonInlinableFunctionSkippingChecker.cpp
   ComputeDominanceInfo.cpp
   ComputeLoopInfo.cpp
   ConstantEvaluatorTester.cpp
@@ -29,6 +28,7 @@ target_sources(swiftSILOptimizer PRIVATE
   RCIdentityDumper.cpp
   SerializeSILPass.cpp
   SILDebugInfoGenerator.cpp
+  SILSkippingChecker.cpp
   SideEffectsDumper.cpp
   SimplifyUnreachableContainingBlocks.cpp
   StripDebugInfo.cpp