From: Michael Liao <michael.hliao@gmail.com>
Date: Thu, 10 Oct 2019 03:14:51 +0000 (+0000)
Subject: [sema] Revise `getCurrentMangleNumberContext` interface. NFC.
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=c9b0a7a79ad699210ce6b375a34963f06ff7e167;p=clang

[sema] Revise `getCurrentMangleNumberContext` interface. NFC.

- Prefer returning mulitple values using a tuple instead of
  additional pointers/references.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@374274 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/clang/Sema/Sema.h b/include/clang/Sema/Sema.h
index 1cc6fc67bc..de7211437e 100644
--- a/include/clang/Sema/Sema.h
+++ b/include/clang/Sema/Sema.h
@@ -57,6 +57,7 @@
 #include <deque>
 #include <memory>
 #include <string>
+#include <tuple>
 #include <vector>
 
 namespace llvm {
@@ -1092,15 +1093,12 @@ public:
   void WarnOnPendingNoDerefs(ExpressionEvaluationContextRecord &Rec);
 
   /// Compute the mangling number context for a lambda expression or
-  /// block literal.
+  /// block literal. Also return the extra mangling decl if any.
   ///
   /// \param DC - The DeclContext containing the lambda expression or
   /// block literal.
-  /// \param[out] ManglingContextDecl - Returns the ManglingContextDecl
-  /// associated with the context, if relevant.
-  MangleNumberingContext *getCurrentMangleNumberContext(
-    const DeclContext *DC,
-    Decl *&ManglingContextDecl);
+  std::tuple<MangleNumberingContext *, Decl *>
+  getCurrentMangleNumberContext(const DeclContext *DC);
 
 
   /// SpecialMemberOverloadResult - The overloading result for a special member
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index a5d95a38a9..7a5edfb945 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -4284,9 +4284,11 @@ void Sema::handleTagNumbering(const TagDecl *Tag, Scope *TagScope) {
   }
 
   // If this tag isn't a direct child of a class, number it if it is local.
+  MangleNumberingContext *MCtx;
   Decl *ManglingContextDecl;
-  if (MangleNumberingContext *MCtx = getCurrentMangleNumberContext(
-          Tag->getDeclContext(), ManglingContextDecl)) {
+  std::tie(MCtx, ManglingContextDecl) =
+      getCurrentMangleNumberContext(Tag->getDeclContext());
+  if (MCtx) {
     Context.setManglingNumber(
         Tag, MCtx->getManglingNumber(
                  Tag, getMSManglingNumber(getLangOpts(), TagScope)));
@@ -5022,9 +5024,11 @@ Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS,
 
   if (VarDecl *NewVD = dyn_cast<VarDecl>(Anon)) {
     if (getLangOpts().CPlusPlus && NewVD->isStaticLocal()) {
+      MangleNumberingContext *MCtx;
       Decl *ManglingContextDecl;
-      if (MangleNumberingContext *MCtx = getCurrentMangleNumberContext(
-              NewVD->getDeclContext(), ManglingContextDecl)) {
+      std::tie(MCtx, ManglingContextDecl) =
+          getCurrentMangleNumberContext(NewVD->getDeclContext());
+      if (MCtx) {
         Context.setManglingNumber(
             NewVD, MCtx->getManglingNumber(
                        NewVD, getMSManglingNumber(getLangOpts(), S)));
@@ -7090,9 +7094,11 @@ NamedDecl *Sema::ActOnVariableDeclarator(
     RegisterLocallyScopedExternCDecl(NewVD, S);
 
   if (getLangOpts().CPlusPlus && NewVD->isStaticLocal()) {
+    MangleNumberingContext *MCtx;
     Decl *ManglingContextDecl;
-    if (MangleNumberingContext *MCtx = getCurrentMangleNumberContext(
-            NewVD->getDeclContext(), ManglingContextDecl)) {
+    std::tie(MCtx, ManglingContextDecl) =
+        getCurrentMangleNumberContext(NewVD->getDeclContext());
+    if (MCtx) {
       Context.setManglingNumber(
           NewVD, MCtx->getManglingNumber(
                      NewVD, getMSManglingNumber(getLangOpts(), S)));
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index 23d3171505..8261ede582 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -14043,10 +14043,11 @@ void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *CurScope) {
   BlockDecl *Block = BlockDecl::Create(Context, CurContext, CaretLoc);
 
   if (LangOpts.CPlusPlus) {
+    MangleNumberingContext *MCtx;
     Decl *ManglingContextDecl;
-    if (MangleNumberingContext *MCtx =
-            getCurrentMangleNumberContext(Block->getDeclContext(),
-                                          ManglingContextDecl)) {
+    std::tie(MCtx, ManglingContextDecl) =
+        getCurrentMangleNumberContext(Block->getDeclContext());
+    if (MCtx) {
       unsigned ManglingNumber = MCtx->getManglingNumber(Block);
       Block->setBlockMangling(ManglingNumber, ManglingContextDecl);
     }
diff --git a/lib/Sema/SemaLambda.cpp b/lib/Sema/SemaLambda.cpp
index b05ed75e87..df4f0ddc6c 100644
--- a/lib/Sema/SemaLambda.cpp
+++ b/lib/Sema/SemaLambda.cpp
@@ -272,12 +272,11 @@ static bool isInInlineFunction(const DeclContext *DC) {
   return false;
 }
 
-MangleNumberingContext *
-Sema::getCurrentMangleNumberContext(const DeclContext *DC,
-                                    Decl *&ManglingContextDecl) {
+std::tuple<MangleNumberingContext *, Decl *>
+Sema::getCurrentMangleNumberContext(const DeclContext *DC) {
   // Compute the context for allocating mangling numbers in the current
   // expression, if the ABI requires them.
-  ManglingContextDecl = ExprEvalContexts.back().ManglingContextDecl;
+  Decl *ManglingContextDecl = ExprEvalContexts.back().ManglingContextDecl;
 
   enum ContextKind {
     Normal,
@@ -325,22 +324,18 @@ Sema::getCurrentMangleNumberContext(const DeclContext *DC,
     if ((IsInNonspecializedTemplate &&
          !(ManglingContextDecl && isa<ParmVarDecl>(ManglingContextDecl))) ||
         isInInlineFunction(CurContext)) {
-      ManglingContextDecl = nullptr;
       while (auto *CD = dyn_cast<CapturedDecl>(DC))
         DC = CD->getParent();
-      return &Context.getManglingNumberContext(DC);
+      return std::make_tuple(&Context.getManglingNumberContext(DC), nullptr);
     }
 
-    ManglingContextDecl = nullptr;
-    return nullptr;
+    return std::make_tuple(nullptr, nullptr);
   }
 
   case StaticDataMember:
     //  -- the initializers of nonspecialized static members of template classes
-    if (!IsInNonspecializedTemplate) {
-      ManglingContextDecl = nullptr;
-      return nullptr;
-    }
+    if (!IsInNonspecializedTemplate)
+      return std::make_tuple(nullptr, nullptr);
     // Fall through to get the current context.
     LLVM_FALLTHROUGH;
 
@@ -352,8 +347,10 @@ Sema::getCurrentMangleNumberContext(const DeclContext *DC,
     //  -- the initializers of inline variables
   case VariableTemplate:
     //  -- the initializers of templated variables
-    return &Context.getManglingNumberContext(ASTContext::NeedExtraManglingDecl,
-                                             ManglingContextDecl);
+    return std::make_tuple(
+        &Context.getManglingNumberContext(ASTContext::NeedExtraManglingDecl,
+                                          ManglingContextDecl),
+        ManglingContextDecl);
   }
 
   llvm_unreachable("unexpected context");
@@ -431,10 +428,11 @@ CXXMethodDecl *Sema::startLambdaDefinition(
   if (Mangling) {
     Class->setLambdaMangling(Mangling->first, Mangling->second);
   } else {
+    MangleNumberingContext *MCtx;
     Decl *ManglingContextDecl;
-    if (MangleNumberingContext *MCtx =
-            getCurrentMangleNumberContext(Class->getDeclContext(),
-                                          ManglingContextDecl)) {
+    std::tie(MCtx, ManglingContextDecl) =
+        getCurrentMangleNumberContext(Class->getDeclContext());
+    if (MCtx) {
       unsigned ManglingNumber = MCtx->getManglingNumber(Method);
       Class->setLambdaMangling(ManglingNumber, ManglingContextDecl);
     }