Merge pull request #26084 from DougGregor/request-evaluator-cross-file-vis

[Request-evaluator] Graphviz visualization of cross-file dependencies

Author: DougGregor

include/swift/AST/AnyRequest.h

@@ -17,6 +17,7 @@
 #ifndef SWIFT_AST_ANYREQUEST_H
 #define SWIFT_AST_ANYREQUEST_H
 
+#include "swift/Basic/SourceLoc.h"
 #include "swift/Basic/TypeID.h"
 #include "llvm/ADT/DenseMapInfo.h"
 #include "llvm/ADT/Hashing.h"
@@ -85,6 +86,9 @@ class AnyRequest {
 
     /// Note that this request is part of a cycle.
     virtual void noteCycleStep(DiagnosticEngine &diags) const = 0;
+
+    /// Retrieve the nearest source location to which this request applies.
+    virtual SourceLoc getNearestLoc() const = 0;
   };
 
   /// Holds a value that can be used as a request input/output.
@@ -125,6 +129,11 @@ class AnyRequest {
     virtual void noteCycleStep(DiagnosticEngine &diags) const override {
       request.noteCycleStep(diags);
     }
+
+    /// Retrieve the nearest source location to which this request applies.
+    virtual SourceLoc getNearestLoc() const override {
+      return request.getNearestLoc();
+    }
   };
 
   /// FIXME: Inefficient. Use the low bits.
@@ -202,6 +211,11 @@ class AnyRequest {
     stored->noteCycleStep(diags);
   }
 
+  /// Retrieve the nearest source location to which this request applies.
+  SourceLoc getNearestLoc() const {
+    return stored->getNearestLoc();
+  }
+
   /// Compare two instances for equality.
   friend bool operator==(const AnyRequest &lhs, const AnyRequest &rhs) {
     if (lhs.storageKind != rhs.storageKind) {

include/swift/AST/DiagnosticEngine.h

@@ -540,10 +540,12 @@ namespace swift {
   /// Class responsible for formatting diagnostics and presenting them
   /// to the user.
   class DiagnosticEngine {
+  public:
     /// The source manager used to interpret source locations and
     /// display diagnostics.
     SourceManager &SourceMgr;
 
+  private:
     /// The diagnostic consumer(s) that will be responsible for actually
     /// emitting diagnostics.
     SmallVector<DiagnosticConsumer *, 2> Consumers;

include/swift/AST/TypeCheckRequests.h

@@ -689,6 +689,28 @@ class LazyStoragePropertyRequest :
   bool isCached() const { return true; }
 };
 
+/// Request to type check the body of the given function.
+///
+/// Produces true if an error occurred, false otherwise.
+/// FIXME: it would be far better to return the type-checked body.
+class TypeCheckFunctionBodyRequest :
+    public SimpleRequest<TypeCheckFunctionBodyRequest,
+                         bool(AbstractFunctionDecl *),
+                         CacheKind::Cached> {
+public:
+  using SimpleRequest::SimpleRequest;
+
+private:
+  friend SimpleRequest;
+
+  // Evaluation.
+  llvm::Expected<bool>
+  evaluate(Evaluator &evaluator, AbstractFunctionDecl *func) const;
+
+public:
+  bool isCached() const { return true; }
+};
+
 // Allow AnyValue to compare two Type values, even though Type doesn't
 // support ==.
 template<>

include/swift/AST/TypeCheckerTypeIDZone.def

@@ -39,4 +39,5 @@ SWIFT_TYPEID(SelfAccessKindRequest)
 SWIFT_TYPEID(IsGetterMutatingRequest)
 SWIFT_TYPEID(IsSetterMutatingRequest)
 SWIFT_TYPEID(OpaqueReadOwnershipRequest)
-SWIFT_TYPEID(LazyStoragePropertyRequest)
+SWIFT_TYPEID(LazyStoragePropertyRequest)
+SWIFT_TYPEID(TypeCheckFunctionBodyRequest)

lib/AST/Evaluator.cpp

@@ -15,7 +15,9 @@
 //
 //===----------------------------------------------------------------------===//
 #include "swift/AST/Evaluator.h"
+#include "swift/AST/DiagnosticEngine.h"
 #include "swift/Basic/Range.h"
+#include "swift/Basic/SourceManager.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/FileSystem.h"
@@ -248,17 +250,47 @@ void Evaluator::printDependenciesGraphviz(llvm::raw_ostream &out) const {
   out << "digraph Dependencies {\n";
 
   // Emit the edges.
+  llvm::DenseMap<AnyRequest, unsigned> inDegree;
   for (const auto &source : allRequests) {
     auto known = dependencies.find(source);
     assert(known != dependencies.end());
     for (const auto &target : known->second) {
       out << "  " << getNodeName(source) << " -> " << getNodeName(target)
           << ";\n";
+      ++inDegree[target];
     }
   }
 
   out << "\n";
 
+  static const char *colorNames[] = {
+    "aquamarine",
+    "blueviolet",
+    "brown",
+    "burlywood",
+    "cadetblue",
+    "chartreuse",
+    "chocolate",
+    "coral",
+    "cornflowerblue",
+    "crimson"
+  };
+  const unsigned numColorNames = sizeof(colorNames) / sizeof(const char *);
+
+  llvm::DenseMap<unsigned, unsigned> knownBuffers;
+  auto getColor = [&](const AnyRequest &request) -> Optional<const char *> {
+    SourceLoc loc = request.getNearestLoc();
+    if (loc.isInvalid())
+      return None;
+
+    unsigned bufferID = diags.SourceMgr.findBufferContainingLoc(loc);
+    auto knownId = knownBuffers.find(bufferID);
+    if (knownId == knownBuffers.end()) {
+      knownId = knownBuffers.insert({bufferID, knownBuffers.size()}).first;
+    }
+    return colorNames[knownId->second % numColorNames];
+  };
+
   // Emit the nodes.
   for (unsigned i : indices(allRequests)) {
     const auto &request = allRequests[i];
@@ -271,7 +303,48 @@ void Evaluator::printDependenciesGraphviz(llvm::raw_ostream &out) const {
       out << " -> ";
       printEscapedString(cachedValue->second.getAsString(), out);
     }
-    out << "\"];\n";
+    out << "\"";
+
+    if (auto color = getColor(request)) {
+      out << ", fillcolor=\"" << *color << "\"";
+    }
+
+    out << "];\n";
+  }
+
+  // Emit "fake" nodes for each of the source buffers we encountered, so
+  // we know which file we're working from.
+  // FIXME: This approximates a "top level" request for, e.g., type checking
+  // an entire source file.
+  std::vector<unsigned> sourceBufferIDs;
+  for (const auto &element : knownBuffers) {
+    sourceBufferIDs.push_back(element.first);
+  }
+  std::sort(sourceBufferIDs.begin(), sourceBufferIDs.end());
+  for (unsigned bufferID : sourceBufferIDs) {
+    out << "  buffer_" << bufferID << "[label=\"";
+    printEscapedString(diags.SourceMgr.getIdentifierForBuffer(bufferID), out);
+    out << "\"";
+
+    out << ", shape=\"box\"";
+    out << ", fillcolor=\""
+        << colorNames[knownBuffers[bufferID] % numColorNames] << "\"";
+    out << "];\n";
+  }
+
+  // Emit "false" dependencies from source buffer IDs to any requests that (1)
+  // have no other incomining edges and (2) can be associated with a source
+  // buffer.
+  for (const auto &request : allRequests) {
+    if (inDegree[request] > 0)
+      continue;
+
+    SourceLoc loc = request.getNearestLoc();
+    if (loc.isInvalid())
+      continue;
+
+    unsigned bufferID = diags.SourceMgr.findBufferContainingLoc(loc);
+    out << "  buffer_" << bufferID << " -> " << getNodeName(request) << ";\n";
   }
 
   // Done!

lib/Sema/TypeCheckStmt.cpp

@@ -29,6 +29,7 @@
 #include "swift/AST/NameLookup.h"
 #include "swift/AST/ParameterList.h"
 #include "swift/AST/PrettyStackTrace.h"
+#include "swift/AST/TypeCheckRequests.h"
 #include "swift/Basic/Range.h"
 #include "swift/Basic/STLExtras.h"
 #include "swift/Basic/SourceManager.h"
@@ -1920,35 +1921,47 @@ bool TypeChecker::typeCheckAbstractFunctionBodyUntil(AbstractFunctionDecl *AFD,
 }
 
 bool TypeChecker::typeCheckAbstractFunctionBody(AbstractFunctionDecl *AFD) {
-  // HACK: don't type-check the same function body twice.  This is
-  // supposed to be handled by just not enqueuing things twice,
-  // but that gets tricky with synthesized function bodies.
-  validateDecl(AFD);
-  (void) AFD->getBody();
+  return evaluateOrDefault(Context.evaluator,
+                           TypeCheckFunctionBodyRequest{AFD},
+                           true);
+}
 
-  if (AFD->isBodyTypeChecked())
+llvm::Expected<bool>
+TypeCheckFunctionBodyRequest::evaluate(Evaluator &evaluator,
+                                       AbstractFunctionDecl *func) const {
+  ASTContext &ctx = func->getASTContext();
+  if (!func->hasInterfaceType()) {
+    TypeChecker &tc = *static_cast<TypeChecker *>(ctx.getLazyResolver());
+    tc.validateDecl(func);
+  }
+
+  // HACK: don't type-check the same function body twice. This will eventually
+  // be handled by the request-evaluator's caching mechanism.
+  (void)func->getBody();
+  if (func->isBodyTypeChecked())
     return false;
 
-  FrontendStatsTracer StatsTracer(Context.Stats, "typecheck-fn", AFD);
-  PrettyStackTraceDecl StackEntry("type-checking", AFD);
+  FrontendStatsTracer StatsTracer(ctx.Stats, "typecheck-fn", func);
+  PrettyStackTraceDecl StackEntry("type-checking", func);
 
-  if (Context.Stats)
-    Context.Stats->getFrontendCounters().NumFunctionsTypechecked++;
+  if (ctx.Stats)
+    ctx.Stats->getFrontendCounters().NumFunctionsTypechecked++;
 
   Optional<FunctionBodyTimer> timer;
-  if (DebugTimeFunctionBodies || WarnLongFunctionBodies)
-    timer.emplace(AFD, DebugTimeFunctionBodies, WarnLongFunctionBodies);
+  TypeChecker &tc = *static_cast<TypeChecker *>(ctx.getLazyResolver());
+  if (tc.DebugTimeFunctionBodies || tc.WarnLongFunctionBodies)
+    timer.emplace(func, tc.DebugTimeFunctionBodies, tc.WarnLongFunctionBodies);
 
-  requestRequiredNominalTypeLayoutForParameters(AFD->getParameters());
+  tc.requestRequiredNominalTypeLayoutForParameters(func->getParameters());
 
-  bool error = typeCheckAbstractFunctionBodyUntil(AFD, SourceLoc());
-  AFD->setBodyTypeCheckedIfPresent();
+  bool error = tc.typeCheckAbstractFunctionBodyUntil(func, SourceLoc());
+  func->setBodyTypeCheckedIfPresent();
 
   if (error)
     return true;
 
-  if (AFD->getBody())
-    performAbstractFuncDeclDiagnostics(*this, AFD);
+  if (func->getBody())
+    performAbstractFuncDeclDiagnostics(tc, func);
 
   return false;
 }

lib/Sema/TypeChecker.h

@@ -631,7 +631,8 @@ class TypeChecker final : public LazyResolver {
   TypeChecker(ASTContext &Ctx);
   friend class ASTContext;
   friend class constraints::ConstraintSystem;
-
+  friend class TypeCheckFunctionBodyRequest;
+  
 public:
   /// Create a new type checker instance for the given ASTContext, if it
   /// doesn't already have one.

test/SourceKit/CursorInfo/cursor_info_property_wrappers.swift

@@ -1,7 +1,7 @@
 @propertyWrapper
 struct Wrapper<T> {
   var wrappedValue: T
-  init(initialValue: T) {
+  init(wrappedValue initialValue: T) {
     wrappedValue = initialValue
   }
   var projectedValue: Projection<T> {
@@ -26,7 +26,7 @@ struct Projection<T> {
 
 // Split between custom attr and initializer
 extension Wrapper {
-    init(initialValue: T, fieldNumber: Int, special: Bool = false) {
+    init(wrappedValue initialValue: T, fieldNumber: Int, special: Bool = false) {
         wrappedValue = initialValue
     }
 }

unittests/AST/ArithmeticEvaluator.cpp

@@ -117,8 +117,7 @@ struct EvaluationRule
     }
   }
 
-  void diagnoseCycle(DiagnosticEngine &diags) const { }
-  void noteCycleStep(DiagnosticEngine &diags) const { }
+  SourceLoc getNearestLoc() const { return SourceLoc(); }
 };
 
 struct InternallyCachedEvaluationRule :