Teach typo correction to properly handle mapping declarations to their

underlying decls. Preserve the found declaration throughout, and only map to
the underlying declaration when we want to check whether it's the right kind.
This allows us to provide the right source location for the found declaration,
and prepares for the possibility of underlying decls with a different name
from the found decl.

llvm-svn: 256575

7 files changed, 27 insertions, 29 deletions

diff --git a/clang/lib/Sema/SemaCXXScopeSpec.cpp b/clang/lib/Sema/SemaCXXScopeSpec.cpp
index 68a1d7368e2..f943a10deb4 100644
--- a/clang/lib/Sema/SemaCXXScopeSpec.cpp
+++ b/clang/lib/Sema/SemaCXXScopeSpec.cpp
@@ -607,7 +607,7 @@ bool Sema::BuildCXXNestedNameSpecifier(Scope *S,
         diagnoseTypo(Corrected, PDiag(diag::err_undeclared_var_use_suggest)
                                   << Name);
 
-      if (NamedDecl *ND = Corrected.getCorrectionDecl())
+      if (NamedDecl *ND = Corrected.getFoundDecl())
         Found.addDecl(ND);
       Found.setLookupName(Corrected.getCorrection());
     } else {
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index 203adeab8d4..aa44f6628de 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -813,9 +813,8 @@ Corrected:
         unsigned UnqualifiedDiag = diag::err_undeclared_var_use_suggest;
         unsigned QualifiedDiag = diag::err_no_member_suggest;
 
-        NamedDecl *FirstDecl = Corrected.getCorrectionDecl();
-        NamedDecl *UnderlyingFirstDecl
-          = FirstDecl? FirstDecl->getUnderlyingDecl() : nullptr;
+        NamedDecl *FirstDecl = Corrected.getFoundDecl();
+        NamedDecl *UnderlyingFirstDecl = Corrected.getCorrectionDecl();
         if (getLangOpts().CPlusPlus && NextToken.is(tok::less) &&
             UnderlyingFirstDecl && isa<TemplateDecl>(UnderlyingFirstDecl)) {
           UnqualifiedDiag = diag::err_no_template_suggest;
diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp
index 9cd3002dd8d..634e699056e 100644
--- a/clang/lib/Sema/SemaDeclCXX.cpp
+++ b/clang/lib/Sema/SemaDeclCXX.cpp
@@ -7531,7 +7531,7 @@ static bool TryNamespaceTypoCorrection(Sema &S, LookupResult &R, Scope *Sc,
                      S.PDiag(diag::err_using_directive_suggest) << Ident,
                      S.PDiag(diag::note_namespace_defined_here));
     }
-    R.addDecl(Corrected.getCorrectionDecl());
+    R.addDecl(Corrected.getFoundDecl());
     return true;
   }
   return false;
diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
index 434b421afb6..888319b395c 100644
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -1776,10 +1776,9 @@ static void emitEmptyLookupTypoDiagnostic(
   std::string CorrectedStr = TC.getAsString(SemaRef.getLangOpts());
   bool DroppedSpecifier =
       TC.WillReplaceSpecifier() && Typo.getAsString() == CorrectedStr;
-  unsigned NoteID =
-      (TC.getCorrectionDecl() && isa<ImplicitParamDecl>(TC.getCorrectionDecl()))
-          ? diag::note_implicit_param_decl
-          : diag::note_previous_decl;
+  unsigned NoteID = TC.getCorrectionDeclAs<ImplicitParamDecl>()
+                        ? diag::note_implicit_param_decl
+                        : diag::note_previous_decl;
   if (!Ctx)
     SemaRef.diagnoseTypo(TC, SemaRef.PDiag(DiagnosticSuggestID) << Typo,
                          SemaRef.PDiag(NoteID));
@@ -1903,7 +1902,7 @@ Sema::DiagnoseEmptyLookup(Scope *S, CXXScopeSpec &SS, LookupResult &R,
 
     bool AcceptableWithRecovery = false;
     bool AcceptableWithoutRecovery = false;
-    NamedDecl *ND = Corrected.getCorrectionDecl();
+    NamedDecl *ND = Corrected.getFoundDecl();
     if (ND) {
       if (Corrected.isOverloaded()) {
         OverloadCandidateSet OCS(R.getNameLoc(),
@@ -1922,7 +1921,7 @@ Sema::DiagnoseEmptyLookup(Scope *S, CXXScopeSpec &SS, LookupResult &R,
         }
         switch (OCS.BestViableFunction(*this, R.getNameLoc(), Best)) {
         case OR_Success:
-          ND = Best->Function;
+          ND = Best->FoundDecl;
           Corrected.setCorrectionDecl(ND);
           break;
         default:
@@ -1944,15 +1943,16 @@ Sema::DiagnoseEmptyLookup(Scope *S, CXXScopeSpec &SS, LookupResult &R,
         R.setNamingClass(Record);
       }
 
-      AcceptableWithRecovery =
-          isa<ValueDecl>(ND) || isa<FunctionTemplateDecl>(ND);
+      auto *UnderlyingND = ND->getUnderlyingDecl();
+      AcceptableWithRecovery = isa<ValueDecl>(UnderlyingND) ||
+                               isa<FunctionTemplateDecl>(UnderlyingND);
       // FIXME: If we ended up with a typo for a type name or
       // Objective-C class name, we're in trouble because the parser
       // is in the wrong place to recover. Suggest the typo
       // correction, but don't make it a fix-it since we're not going
       // to recover well anyway.
       AcceptableWithoutRecovery =
-          isa<TypeDecl>(ND) || isa<ObjCInterfaceDecl>(ND);
+          isa<TypeDecl>(UnderlyingND) || isa<ObjCInterfaceDecl>(UnderlyingND);
     } else {
       // FIXME: We found a keyword. Suggest it, but don't provide a fix-it
       // because we aren't able to recover.
@@ -1960,8 +1960,7 @@ Sema::DiagnoseEmptyLookup(Scope *S, CXXScopeSpec &SS, LookupResult &R,
     }
 
     if (AcceptableWithRecovery || AcceptableWithoutRecovery) {
-      unsigned NoteID = (Corrected.getCorrectionDecl() &&
-                         isa<ImplicitParamDecl>(Corrected.getCorrectionDecl()))
+      unsigned NoteID = Corrected.getCorrectionDeclAs<ImplicitParamDecl>()
                             ? diag::note_implicit_param_decl
                             : diag::note_previous_decl;
       if (SS.isEmpty())
@@ -4402,7 +4401,7 @@ static TypoCorrection TryTypoCorrectionForCall(Sema &S, Expr *Fn,
           llvm::make_unique<FunctionCallCCC>(S, FuncName.getAsIdentifierInfo(),
                                              Args.size(), ME),
           Sema::CTK_ErrorRecovery)) {
-    if (NamedDecl *ND = Corrected.getCorrectionDecl()) {
+    if (NamedDecl *ND = Corrected.getFoundDecl()) {
       if (Corrected.isOverloaded()) {
         OverloadCandidateSet OCS(NameLoc, OverloadCandidateSet::CSK_Normal);
         OverloadCandidateSet::iterator Best;
@@ -4413,16 +4412,16 @@ static TypoCorrection TryTypoCorrectionForCall(Sema &S, Expr *Fn,
         }
         switch (OCS.BestViableFunction(S, NameLoc, Best)) {
         case OR_Success:
-          ND = Best->Function;
+          ND = Best->FoundDecl;
           Corrected.setCorrectionDecl(ND);
           break;
         default:
           break;
         }
       }
-      if (isa<ValueDecl>(ND) || isa<FunctionTemplateDecl>(ND)) {
+      ND = ND->getUnderlyingDecl();
+      if (isa<ValueDecl>(ND) || isa<FunctionTemplateDecl>(ND))
         return Corrected;
-      }
     }
   }
   return TypoCorrection();
diff --git a/clang/lib/Sema/SemaExprCXX.cpp b/clang/lib/Sema/SemaExprCXX.cpp
index 47d15c363c9..2ad595f3a81 100644
--- a/clang/lib/Sema/SemaExprCXX.cpp
+++ b/clang/lib/Sema/SemaExprCXX.cpp
@@ -6409,7 +6409,7 @@ static ExprResult attemptRecovery(Sema &SemaRef,
   else if (SS && !TC.WillReplaceSpecifier())
     NewSS = *SS;
 
-  if (auto *ND = TC.getCorrectionDecl()) {
+  if (auto *ND = TC.getFoundDecl()) {
     R.setLookupName(ND->getDeclName());
     R.addDecl(ND);
     if (ND->isCXXClassMember()) {
@@ -6530,9 +6530,9 @@ class TransformTypos : public TreeTransform<TransformTypos> {
     if (!E)
       return nullptr;
     if (auto *DRE = dyn_cast<DeclRefExpr>(E))
-      return DRE->getDecl();
+      return DRE->getFoundDecl();
     if (auto *ME = dyn_cast<MemberExpr>(E))
-      return ME->getMemberDecl();
+      return ME->getFoundDecl();
     // FIXME: Add any other expr types that could be be seen by the delayed typo
     // correction TreeTransform for which the corresponding TypoCorrection could
     // contain multiple decls.
@@ -6637,7 +6637,7 @@ public:
     // For the first TypoExpr and an uncached TypoExpr, find the next likely
     // typo correction and return it.
     while (TypoCorrection TC = State.Consumer->getNextCorrection()) {
-      if (InitDecl && TC.getCorrectionDecl() == InitDecl)
+      if (InitDecl && TC.getFoundDecl() == InitDecl)
         continue;
       ExprResult NE = State.RecoveryHandler ?
           State.RecoveryHandler(SemaRef, E, TC) :
diff --git a/clang/lib/Sema/SemaLookup.cpp b/clang/lib/Sema/SemaLookup.cpp
index 2aeffd82b76..481ae6cd55b 100644
--- a/clang/lib/Sema/SemaLookup.cpp
+++ b/clang/lib/Sema/SemaLookup.cpp
@@ -4719,7 +4719,7 @@ void TypoCorrection::addCorrectionDecl(NamedDecl *CDecl) {
   if (isKeyword())
     CorrectionDecls.clear();
 
-  CorrectionDecls.push_back(CDecl->getUnderlyingDecl());
+  CorrectionDecls.push_back(CDecl);
 
   if (!CorrectionName)
     CorrectionName = CDecl->getDeclName();
@@ -4948,7 +4948,7 @@ void Sema::diagnoseTypo(const TypoCorrection &Correction,
 
   // Maybe we're just missing a module import.
   if (Correction.requiresImport()) {
-    NamedDecl *Decl = Correction.getCorrectionDecl();
+    NamedDecl *Decl = Correction.getFoundDecl();
     assert(Decl && "import required but no declaration to import");
 
     diagnoseMissingImport(Correction.getCorrectionRange().getBegin(), Decl,
@@ -4960,7 +4960,7 @@ void Sema::diagnoseTypo(const TypoCorrection &Correction,
     << CorrectedQuotedStr << (ErrorRecovery ? FixTypo : FixItHint());
 
   NamedDecl *ChosenDecl =
-      Correction.isKeyword() ? nullptr : Correction.getCorrectionDecl();
+      Correction.isKeyword() ? nullptr : Correction.getFoundDecl();
   if (PrevNote.getDiagID() && ChosenDecl)
     Diag(ChosenDecl->getLocation(), PrevNote)
       << CorrectedQuotedStr << (ErrorRecovery ? FixItHint() : FixTypo);
diff --git a/clang/lib/Sema/SemaTemplate.cpp b/clang/lib/Sema/SemaTemplate.cpp
index 4b130229b6c..6cc85883345 100644
--- a/clang/lib/Sema/SemaTemplate.cpp
+++ b/clang/lib/Sema/SemaTemplate.cpp
@@ -329,8 +329,8 @@ void Sema::LookupTemplateName(LookupResult &Found,
             Found.getLookupNameInfo(), Found.getLookupKind(), S, &SS,
             std::move(FilterCCC), CTK_ErrorRecovery, LookupCtx)) {
       Found.setLookupName(Corrected.getCorrection());
-      if (Corrected.getCorrectionDecl())
-        Found.addDecl(Corrected.getCorrectionDecl());
+      if (auto *ND = Corrected.getFoundDecl())
+        Found.addDecl(ND);
       FilterAcceptableTemplateNames(Found);
       if (!Found.empty()) {
         if (LookupCtx) {