Add a “typecheck module interface” mode

Author: beccadax

include/swift/Frontend/FrontendOptions.h

@@ -116,6 +116,8 @@ class FrontendOptions {
 
     /// Build from a swiftinterface, as close to `import` as possible
     CompileModuleFromInterface,
+    /// Same as CompileModuleFromInterface, but stopping after typechecking
+    TypecheckModuleFromInterface,
 
     EmitSIBGen, ///< Emit serialized AST + raw SIL
     EmitSIB,    ///< Emit serialized AST + canonical SIL

include/swift/Frontend/ModuleInterfaceLoader.h

@@ -263,6 +263,8 @@ class ExplicitModuleMapParser {
 };
 
 struct ModuleInterfaceLoaderOptions {
+  FrontendOptions::ActionType requestedAction =
+      FrontendOptions::ActionType::EmitModuleOnly;
   bool remarkOnRebuildFromInterface = false;
   bool disableInterfaceLock = false;
   bool disableImplicitSwiftModule = false;
@@ -271,7 +273,17 @@ struct ModuleInterfaceLoaderOptions {
     remarkOnRebuildFromInterface(Opts.RemarkOnRebuildFromModuleInterface),
     disableInterfaceLock(Opts.DisableInterfaceFileLock),
     disableImplicitSwiftModule(Opts.DisableImplicitModules),
-    mainExecutablePath(Opts.MainExecutablePath) {}
+    mainExecutablePath(Opts.MainExecutablePath)
+  {
+    switch (Opts.RequestedAction) {
+    case FrontendOptions::ActionType::TypecheckModuleFromInterface:
+      requestedAction = FrontendOptions::ActionType::Typecheck;
+      break;
+    default:
+      requestedAction = FrontendOptions::ActionType::EmitModuleOnly;
+      break;
+    }
+  }
   ModuleInterfaceLoaderOptions() = default;
 };
 

include/swift/Option/FrontendOptions.td

@@ -641,6 +641,11 @@ def build_module_from_parseable_interface :
   Alias<compile_module_from_interface>,
   ModeOpt;
 
+def typecheck_module_from_interface :
+  Flag<["-"], "typecheck-module-from-interface">,
+  HelpText<"Treat the (single) input as a swiftinterface and typecheck it">,
+  ModeOpt;
+
 def module_interface_preserve_types_as_written :
   Flag<["-"], "module-interface-preserve-types-as-written">,
   HelpText<"When emitting a module interface, preserve types as they were "

lib/Frontend/ArgsToFrontendOptionsConverter.cpp

@@ -147,7 +147,8 @@ bool ArgsToFrontendOptionsConverter::convert(
     Opts.RequestedAction = determineRequestedAction(Args);
   }
 
-  if (Opts.RequestedAction == FrontendOptions::ActionType::CompileModuleFromInterface) {
+  if (Opts.RequestedAction == FrontendOptions::ActionType::CompileModuleFromInterface ||
+      Opts.RequestedAction == FrontendOptions::ActionType::TypecheckModuleFromInterface) {
     // The situations where we use this action, e.g. explicit module building and
     // generating prebuilt module cache, don't need synchronization. We should avoid
     // using lock files for them.
@@ -389,6 +390,8 @@ ArgsToFrontendOptionsConverter::determineRequestedAction(const ArgList &args) {
     return FrontendOptions::ActionType::Immediate;
   if (Opt.matches(OPT_compile_module_from_interface))
     return FrontendOptions::ActionType::CompileModuleFromInterface;
+  if (Opt.matches(OPT_typecheck_module_from_interface))
+    return FrontendOptions::ActionType::TypecheckModuleFromInterface;
 
   llvm_unreachable("Unhandled mode option");
 }

lib/Frontend/Frontend.cpp

@@ -192,7 +192,9 @@ void CompilerInstance::recordPrimaryInputBuffer(unsigned BufID) {
 
 bool CompilerInstance::setUpASTContextIfNeeded() {
   if (Invocation.getFrontendOptions().RequestedAction ==
-      FrontendOptions::ActionType::CompileModuleFromInterface) {
+          FrontendOptions::ActionType::CompileModuleFromInterface ||
+      Invocation.getFrontendOptions().RequestedAction ==
+          FrontendOptions::ActionType::TypecheckModuleFromInterface) {
     // Compiling a module interface from source uses its own CompilerInstance
     // with options read from the input file. Don't bother setting up an
     // ASTContext at this level.

lib/Frontend/FrontendOptions.cpp

@@ -51,6 +51,7 @@ bool FrontendOptions::needsProperModuleName(ActionType action) {
   case ActionType::EmitModuleOnly:
   case ActionType::MergeModules:
   case ActionType::CompileModuleFromInterface:
+  case ActionType::TypecheckModuleFromInterface:
     return true;
   case ActionType::Immediate:
   case ActionType::REPL:
@@ -118,6 +119,7 @@ FrontendOptions::formatForPrincipalOutputFileForAction(ActionType action) {
   case ActionType::Parse:
   case ActionType::ResolveImports:
   case ActionType::Typecheck:
+  case ActionType::TypecheckModuleFromInterface:
   case ActionType::DumpParse:
   case ActionType::DumpInterfaceHash:
   case ActionType::DumpAST:
@@ -192,6 +194,7 @@ bool FrontendOptions::canActionEmitDependencies(ActionType action) {
   case ActionType::DumpTypeRefinementContexts:
   case ActionType::DumpTypeInfo:
   case ActionType::CompileModuleFromInterface:
+  case ActionType::TypecheckModuleFromInterface:
   case ActionType::Immediate:
   case ActionType::REPL:
   case ActionType::DumpPCM:
@@ -232,6 +235,7 @@ bool FrontendOptions::canActionEmitReferenceDependencies(ActionType action) {
   case ActionType::DumpTypeRefinementContexts:
   case ActionType::DumpTypeInfo:
   case ActionType::CompileModuleFromInterface:
+  case ActionType::TypecheckModuleFromInterface:
   case ActionType::Immediate:
   case ActionType::REPL:
   case ActionType::EmitPCM:
@@ -280,6 +284,7 @@ bool FrontendOptions::canActionEmitObjCHeader(ActionType action) {
   case ActionType::DumpTypeRefinementContexts:
   case ActionType::DumpTypeInfo:
   case ActionType::CompileModuleFromInterface:
+  case ActionType::TypecheckModuleFromInterface:
   case ActionType::Immediate:
   case ActionType::REPL:
   case ActionType::EmitPCM:
@@ -317,6 +322,7 @@ bool FrontendOptions::canActionEmitLoadedModuleTrace(ActionType action) {
   case ActionType::DumpTypeRefinementContexts:
   case ActionType::DumpTypeInfo:
   case ActionType::CompileModuleFromInterface:
+  case ActionType::TypecheckModuleFromInterface:
   case ActionType::Immediate:
   case ActionType::REPL:
   case ActionType::EmitPCM:
@@ -360,6 +366,7 @@ bool FrontendOptions::canActionEmitModule(ActionType action) {
   case ActionType::DumpTypeInfo:
   case ActionType::EmitSILGen:
   case ActionType::CompileModuleFromInterface:
+  case ActionType::TypecheckModuleFromInterface:
   case ActionType::Immediate:
   case ActionType::REPL:
   case ActionType::EmitPCM:
@@ -404,6 +411,7 @@ bool FrontendOptions::canActionEmitInterface(ActionType action) {
   case ActionType::EmitSILGen:
   case ActionType::EmitSIBGen:
   case ActionType::CompileModuleFromInterface:
+  case ActionType::TypecheckModuleFromInterface:
   case ActionType::Immediate:
   case ActionType::REPL:
   case ActionType::EmitPCM:
@@ -450,6 +458,7 @@ bool FrontendOptions::doesActionProduceOutput(ActionType action) {
   case ActionType::EmitImportedModules:
   case ActionType::MergeModules:
   case ActionType::CompileModuleFromInterface:
+  case ActionType::TypecheckModuleFromInterface:
   case ActionType::DumpTypeInfo:
   case ActionType::EmitPCM:
   case ActionType::DumpPCM:
@@ -484,6 +493,7 @@ bool FrontendOptions::doesActionProduceTextualOutput(ActionType action) {
   case ActionType::Parse:
   case ActionType::ResolveImports:
   case ActionType::Typecheck:
+  case ActionType::TypecheckModuleFromInterface:
   case ActionType::DumpParse:
   case ActionType::DumpInterfaceHash:
   case ActionType::DumpAST:
@@ -521,6 +531,7 @@ bool FrontendOptions::doesActionGenerateSIL(ActionType action) {
   case ActionType::EmitImportedModules:
   case ActionType::EmitPCH:
   case ActionType::CompileModuleFromInterface:
+  case ActionType::TypecheckModuleFromInterface:
   case ActionType::EmitPCM:
   case ActionType::DumpPCM:
   case ActionType::ScanDependencies:
@@ -557,6 +568,7 @@ bool FrontendOptions::doesActionGenerateIR(ActionType action) {
   case ActionType::DumpTypeRefinementContexts:
   case ActionType::DumpTypeInfo:
   case ActionType::CompileModuleFromInterface:
+  case ActionType::TypecheckModuleFromInterface:
   case ActionType::Typecheck:
   case ActionType::ResolveImports:
   case ActionType::MergeModules:

lib/Frontend/ModuleInterfaceBuilder.cpp

@@ -176,6 +176,8 @@ bool ModuleInterfaceBuilder::buildSwiftModuleInternal(
       return false;
     }
     FrontendOptions &FEOpts = subInvocation.getFrontendOptions();
+    bool isTypeChecking =
+        (FEOpts.RequestedAction == FrontendOptions::ActionType::Typecheck);
     const auto &InputInfo = FEOpts.InputsAndOutputs.firstInput();
     StringRef InPath = InputInfo.file();
     const auto &OutputInfo =
@@ -242,6 +244,9 @@ bool ModuleInterfaceBuilder::buildSwiftModuleInternal(
     if (ShouldSerializeDeps)
       SerializationOpts.Dependencies = Deps;
     SILMod->setSerializeSILAction([&]() {
+      if (isTypeChecking)
+        return;
+
       // We don't want to serialize module docs in the cache -- they
       // will be serialized beside the interface file.
       serializeToBuffers(Mod, SerializationOpts, ModuleBuffer,

lib/Frontend/ModuleInterfaceLoader.cpp

@@ -1259,7 +1259,7 @@ InterfaceSubContextDelegateImpl::InterfaceSubContextDelegateImpl(
   inheritOptionsForBuildingInterface(searchPathOpts, langOpts);
   // Configure front-end input.
   auto &SubFEOpts = genericSubInvocation.getFrontendOptions();
-  SubFEOpts.RequestedAction = FrontendOptions::ActionType::EmitModuleOnly;
+  SubFEOpts.RequestedAction = LoaderOpts.requestedAction;
   if (!moduleCachePath.empty()) {
     genericSubInvocation.setClangModuleCachePath(moduleCachePath);
   }
@@ -1442,7 +1442,10 @@ bool InterfaceSubContextDelegateImpl::runInSubCompilerInstance(StringRef moduleN
   std::vector<std::string> outputFiles{"/<unused>"};
   std::vector<SupplementaryOutputPaths> ModuleOutputPaths;
   ModuleOutputPaths.emplace_back();
-  ModuleOutputPaths.back().ModuleOutputPath = outputPath.str();
+  if (subInvocation.getFrontendOptions().RequestedAction ==
+          FrontendOptions::ActionType::EmitModuleOnly) {
+    ModuleOutputPaths.back().ModuleOutputPath = outputPath.str();
+  }
   assert(subInvocation.getFrontendOptions().InputsAndOutputs.isWholeModule());
   subInvocation.getFrontendOptions().InputsAndOutputs
     .setMainAndSupplementaryOutputs(outputFiles, ModuleOutputPaths);

lib/FrontendTool/FrontendTool.cpp

@@ -1711,7 +1711,8 @@ static bool performCompile(CompilerInstance &Instance,
       << Invocation.getLangOptions().Target.str() << '\n';
     return false;
   }
-  if (Action == FrontendOptions::ActionType::CompileModuleFromInterface)
+  if (Action == FrontendOptions::ActionType::CompileModuleFromInterface ||
+      Action == FrontendOptions::ActionType::TypecheckModuleFromInterface)
     return buildModuleFromInterface(Instance);
 
   if (Invocation.getInputKind() == InputFileKind::LLVM)

test/ModuleInterface/unbuildable.swift

@@ -14,8 +14,15 @@
 //
 // And finally, test:
 //
-// RUN: not %target-swift-frontend -typecheck %s -I %t -DCURRENT 2>&1 | %FileCheck -check-prefix=CURRENT %s
-// RUN: not %target-swift-frontend -typecheck %s -I %t -DFUTURE 2>&1 | %FileCheck -check-prefix=FUTURE %s
+// RUN: not %target-swift-frontend -typecheck %s -I %t -DCURRENT 2>&1 | %FileCheck -check-prefixes=ALL,CURRENT %s
+// RUN: not %target-swift-frontend -typecheck %s -I %t -DFUTURE 2>&1 | %FileCheck -check-prefixes=ALL,FUTURE %s
+//
+// Test that we get the same results when typechecking the interface:
+//
+// RUN: not %target-swift-frontend -typecheck-module-from-interface %t/UnbuildableCurrent.swiftinterface 2>&1 | %FileCheck -check-prefixes=ALL,CURRENT-PREBUILD %s
+// RUN: not %target-swift-frontend -typecheck-module-from-interface %t/UnbuildableFuture.swiftinterface 2>&1 | %FileCheck -check-prefixes=ALL,FUTURE-PREBUILD %s
+
+// ALL: Unbuildable{{[^.]+}}.swiftinterface:{{[0-9]+}}:{{[0-9]+}}: error: use of unknown directive '#somethingYouveNeverHeardOf'
 
 #if CURRENT
 import UnbuildableCurrent
@@ -25,3 +32,5 @@ import UnbuildableFuture
 // FUTURE: unbuildable.swift:[[@LINE-1]]:8: error: failed to build module 'UnbuildableFuture' from its module interface; the compiler that produced it, 'NeoTokyoSwift 2000.42', may have used features that aren't supported by this compiler, '{{.*Swift version.*}}'
 #endif
 
+// CURRENT-PREBUILD: UnbuildableCurrent.swiftinterface:1:1: error: failed to build module 'UnbuildableCurrent' from its module interface; it may have been damaged or it may have triggered a bug in the Swift compiler when it was produced
+// FUTURE-PREBUILD: UnbuildableFuture.swiftinterface:1:1: error: failed to build module 'UnbuildableFuture' from its module interface; the compiler that produced it, 'NeoTokyoSwift 2000.42', may have used features that aren't supported by this compiler, '{{.*Swift version.*}}'