IDE: cache resolved cursor info in the request evaluator

Resolving cursor info is a necessary step both when checking the availability
of a refactoring kind and performing the refactoring action. These
two steps are two high-level sourcekitd requests issued from IDE.
By caching the result of the resolved cursor info in the evaluator of
the ASTContext, we can reuse the cursor info result across these separate
IDE requests.

Author: nkcsgexi

include/swift/IDE/IDERequests.h

@@ -20,6 +20,7 @@
 #include "swift/AST/Evaluator.h"
 #include "swift/AST/SimpleRequest.h"
 #include "swift/IDE/Utils.h"
+#include "swift/IDE/IDETypeIDs.h"
 
 namespace swift {
 
@@ -56,7 +57,7 @@ void simple_display(llvm::raw_ostream &out, const CursorInfoOwner &owner);
 class CursorInfoRequest:
     public SimpleRequest<CursorInfoRequest,
                          ide::ResolvedCursorInfo(CursorInfoOwner),
-                         CacheKind::Uncached> // FIXME: cache these
+                         CacheKind::Cached>
 {
 public:
   using SimpleRequest::SimpleRequest;

include/swift/IDE/IDETypeIDZone.def

@@ -0,0 +1,17 @@
+//===---------- IDETypeIDZone.def ------------------------------*- C++ -*-===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2014 - 2019 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
+//
+//===----------------------------------------------------------------------===//
+//
+//  This definition file describes the types in the IDE type
+//  TypeID zone, for use with the TypeID template.
+//
+//===----------------------------------------------------------------------===//
+SWIFT_TYPEID_NAMED(ide::ResolvedCursorInfo, ResolvedCursorInfo)

include/swift/IDE/IDETypeIDs.h

@@ -0,0 +1,30 @@
+//===--- IDETypeIDs.h - IDE Type Ids ----------------------------*- C++ -*-===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2019 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
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file defines TypeID support for IDE types.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef SWIFT_IDE_IDETYPEIDS_H
+#define SWIFT_IDE_IDETYPEIDS_H
+
+#include "swift/Basic/TypeID.h"
+namespace swift {
+
+#define SWIFT_IDE_TYPEID_ZONE 136
+#define SWIFT_TYPEID_ZONE SWIFT_IDE_TYPEID_ZONE
+#define SWIFT_TYPEID_HEADER "swift/IDE/IDETypeIDZone.def"
+#include "swift/Basic/DefineTypeIDZone.h"
+
+} // end namespace swift
+
+#endif // SWIFT_IDE_IDETYPEIDS_H

include/swift/IDE/Utils.h

@@ -163,7 +163,13 @@ struct ResolvedCursorInfo {
 
   ResolvedCursorInfo() = default;
   ResolvedCursorInfo(SourceFile *SF) : SF(SF) {}
-  
+
+  friend bool operator==(const ResolvedCursorInfo &lhs,
+                         const ResolvedCursorInfo &rhs) {
+    return lhs.SF == rhs.SF &&
+      lhs.Loc.getOpaquePointerValue() == rhs.Loc.getOpaquePointerValue();
+  }
+
   void setValueRef(ValueDecl *ValueD,
                    TypeDecl *CtorTyRef,
                    ExtensionDecl *ExtTyRef,
@@ -196,6 +202,8 @@ struct ResolvedCursorInfo {
   bool isInvalid() const { return Kind == CursorInfoKind::Invalid; }
 };
 
+void simple_display(llvm::raw_ostream &out, const ResolvedCursorInfo &info);
+
 struct UnresolvedLoc {
   SourceLoc Loc;
   bool ResolveArgLocs;

lib/IDE/IDERequests.cpp

@@ -303,6 +303,17 @@ void swift::simple_display(llvm::raw_ostream &out, const CursorInfoOwner &owner)
   out << ":" << LC.first << ":" << LC.second;
 }
 
+void swift::ide::simple_display(llvm::raw_ostream &out,
+                                const ide::ResolvedCursorInfo &info) {
+  if (info.isInvalid())
+    return;
+  out << "Resolved cursor info at ";
+  auto &SM = info.SF->getASTContext().SourceMgr;
+  out << SM.getIdentifierForBuffer(*info.SF->getBufferID());
+  auto LC = SM.getLineAndColumn(info.Loc);
+  out << ":" << LC.first << ":" << LC.second;
+}
+
 // Define request evaluation functions for each of the IDE requests.
 static AbstractRequestFunction *ideRequestFunctions[] = {
 #define SWIFT_TYPEID(Name)                                    \