Revert "[MS] Improved implementation of MS stack pragmas (vtordisp, *_seg)"

This reverts commit r267866.

llvm-svn: 267870

4 files changed, 36 insertions, 22 deletions

diff --git a/clang/lib/Parse/ParsePragma.cpp b/clang/lib/Parse/ParsePragma.cpp
index adeac132b00..2352fbe4d8d 100644
--- a/clang/lib/Parse/ParsePragma.cpp
+++ b/clang/lib/Parse/ParsePragma.cpp
@@ -497,11 +497,11 @@ void Parser::HandlePragmaMSPointersToMembers() {
 void Parser::HandlePragmaMSVtorDisp() {
   assert(Tok.is(tok::annot_pragma_ms_vtordisp));
   uintptr_t Value = reinterpret_cast<uintptr_t>(Tok.getAnnotationValue());
-  Sema::PragmaMsStackAction Action =
-      static_cast<Sema::PragmaMsStackAction>((Value >> 16) & 0xFFFF);
+  Sema::PragmaVtorDispKind Kind =
+      static_cast<Sema::PragmaVtorDispKind>((Value >> 16) & 0xFFFF);
   MSVtorDispAttr::Mode Mode = MSVtorDispAttr::Mode(Value & 0xFFFF);
   SourceLocation PragmaLoc = ConsumeToken(); // The annotation token.
-  Actions.ActOnPragmaMSVtorDisp(Action, PragmaLoc, Mode);
+  Actions.ActOnPragmaMSVtorDisp(Kind, PragmaLoc, Mode);
 }
 
 void Parser::HandlePragmaMSPragma() {
@@ -1606,7 +1606,7 @@ void PragmaMSVtorDisp::HandlePragma(Preprocessor &PP,
   }
   PP.Lex(Tok);
 
-  Sema::PragmaMsStackAction Action = Sema::PSK_Set;
+  Sema::PragmaVtorDispKind Kind = Sema::PVDK_Set;
   const IdentifierInfo *II = Tok.getIdentifierInfo();
   if (II) {
     if (II->isStr("push")) {
@@ -1617,24 +1617,24 @@ void PragmaMSVtorDisp::HandlePragma(Preprocessor &PP,
         return;
       }
       PP.Lex(Tok);
-      Action = Sema::PSK_Push_Set;
+      Kind = Sema::PVDK_Push;
       // not push, could be on/off
     } else if (II->isStr("pop")) {
       // #pragma vtordisp(pop)
       PP.Lex(Tok);
-      Action = Sema::PSK_Pop;
+      Kind = Sema::PVDK_Pop;
     }
     // not push or pop, could be on/off
   } else {
     if (Tok.is(tok::r_paren)) {
       // #pragma vtordisp()
-      Action = Sema::PSK_Reset;
+      Kind = Sema::PVDK_Reset;
     }
   }
 
 
   uint64_t Value = 0;
-  if (Action & Sema::PSK_Push || Action & Sema::PSK_Set) {
+  if (Kind == Sema::PVDK_Push || Kind == Sema::PVDK_Set) {
     const IdentifierInfo *II = Tok.getIdentifierInfo();
     if (II && II->isStr("off")) {
       PP.Lex(Tok);
@@ -1676,7 +1676,7 @@ void PragmaMSVtorDisp::HandlePragma(Preprocessor &PP,
   AnnotTok.setLocation(VtorDispLoc);
   AnnotTok.setAnnotationEndLoc(EndLoc);
   AnnotTok.setAnnotationValue(reinterpret_cast<void *>(
-      static_cast<uintptr_t>((Action << 16) | (Value & 0xFFFF))));
+      static_cast<uintptr_t>((Kind << 16) | (Value & 0xFFFF))));
   PP.EnterToken(AnnotTok);
 }
 
diff --git a/clang/lib/Parse/ParseStmt.cpp b/clang/lib/Parse/ParseStmt.cpp
index 69989fe522e..085319f9bdd 100644
--- a/clang/lib/Parse/ParseStmt.cpp
+++ b/clang/lib/Parse/ParseStmt.cpp
@@ -1928,8 +1928,7 @@ Decl *Parser::ParseFunctionStatementBody(Decl *Decl, ParseScope &BodyScope) {
   // Save and reset current vtordisp stack if we have entered a C++ method body.
   bool IsCXXMethod =
       getLangOpts().CPlusPlus && Decl && isa<CXXMethodDecl>(Decl);
-  Sema::PragmaStackSentinelRAII
-    PragmaStackSentinel(Actions, "InternalPragmaState", IsCXXMethod);
+  Sema::VtorDispStackRAII SavedVtorDispStack(Actions, IsCXXMethod);
 
   // Do not enter a scope for the brace, as the arguments are in the same scope
   // (the function body) as the body itself.  Instead, just read the statement
@@ -1973,8 +1972,7 @@ Decl *Parser::ParseFunctionTryBlock(Decl *Decl, ParseScope &BodyScope) {
   // Save and reset current vtordisp stack if we have entered a C++ method body.
   bool IsCXXMethod =
       getLangOpts().CPlusPlus && Decl && isa<CXXMethodDecl>(Decl);
-  Sema::PragmaStackSentinelRAII
-    PragmaStackSentinel(Actions, "InternalPragmaState", IsCXXMethod);
+  Sema::VtorDispStackRAII SavedVtorDispStack(Actions, IsCXXMethod);
 
   SourceLocation LBraceLoc = Tok.getLocation();
   StmtResult FnBody(ParseCXXTryBlockCommon(TryLoc, /*FnTry*/true));
diff --git a/clang/lib/Sema/Sema.cpp b/clang/lib/Sema/Sema.cpp
index 07a2657177d..5a8e5510f75 100644
--- a/clang/lib/Sema/Sema.cpp
+++ b/clang/lib/Sema/Sema.cpp
@@ -82,7 +82,7 @@ Sema::Sema(Preprocessor &pp, ASTContext &ctxt, ASTConsumer &consumer,
     PackContext(nullptr), MSStructPragmaOn(false),
     MSPointerToMemberRepresentationMethod(
         LangOpts.getMSPointerToMemberRepresentationMethod()),
-    VtorDispStack(MSVtorDispAttr::Mode(LangOpts.VtorDispMode)),
+    VtorDispModeStack(1, MSVtorDispAttr::Mode(LangOpts.VtorDispMode)),
     DataSegStack(nullptr), BSSSegStack(nullptr), ConstSegStack(nullptr),
     CodeSegStack(nullptr), CurInitSeg(nullptr), VisContext(nullptr),
     IsBuildingRecoveryCallExpr(false),
diff --git a/clang/lib/Sema/SemaAttr.cpp b/clang/lib/Sema/SemaAttr.cpp
index 8474cf8b7cb..7f523c465af 100644
--- a/clang/lib/Sema/SemaAttr.cpp
+++ b/clang/lib/Sema/SemaAttr.cpp
@@ -136,9 +136,9 @@ void Sema::AddMsStructLayoutForRecord(RecordDecl *RD) {
   // FIXME: We should merge AddAlignmentAttributesForRecord with
   // AddMsStructLayoutForRecord into AddPragmaAttributesForRecord, which takes
   // all active pragmas and applies them as attributes to class definitions.
-  if (VtorDispStack.CurrentValue != getLangOpts().VtorDispMode)
+  if (VtorDispModeStack.back() != getLangOpts().VtorDispMode)
     RD->addAttr(
-        MSVtorDispAttr::CreateImplicit(Context, VtorDispStack.CurrentValue));
+        MSVtorDispAttr::CreateImplicit(Context, VtorDispModeStack.back()));
 }
 
 void Sema::ActOnPragmaOptionsAlign(PragmaOptionsAlignKind Kind,
@@ -292,13 +292,29 @@ void Sema::ActOnPragmaMSPointersToMembers(
   ImplicitMSInheritanceAttrLoc = PragmaLoc;
 }
 
-void Sema::ActOnPragmaMSVtorDisp(PragmaMsStackAction Action,
+void Sema::ActOnPragmaMSVtorDisp(PragmaVtorDispKind Kind,
                                  SourceLocation PragmaLoc,
                                  MSVtorDispAttr::Mode Mode) {
-  if (Action & PSK_Pop && VtorDispStack.Stack.empty())
-    Diag(PragmaLoc, diag::warn_pragma_pop_failed) << "vtordisp"
-                                                  << "stack empty";
-  VtorDispStack.Act(PragmaLoc, Action, StringRef(), Mode);
+  switch (Kind) {
+  case PVDK_Set:
+    VtorDispModeStack.back() = Mode;
+    break;
+  case PVDK_Push:
+    VtorDispModeStack.push_back(Mode);
+    break;
+  case PVDK_Reset:
+    VtorDispModeStack.clear();
+    VtorDispModeStack.push_back(MSVtorDispAttr::Mode(LangOpts.VtorDispMode));
+    break;
+  case PVDK_Pop:
+    VtorDispModeStack.pop_back();
+    if (VtorDispModeStack.empty()) {
+      Diag(PragmaLoc, diag::warn_pragma_pop_failed) << "vtordisp"
+                                                    << "stack empty";
+      VtorDispModeStack.push_back(MSVtorDispAttr::Mode(LangOpts.VtorDispMode));
+    }
+    break;
+  }
 }
 
 template<typename ValueType>
@@ -307,7 +323,7 @@ void Sema::PragmaStack<ValueType>::Act(SourceLocation PragmaLocation,
                                        llvm::StringRef StackSlotLabel,
                                        ValueType Value) {
   if (Action == PSK_Reset) {
-    CurrentValue = DefaultValue;
+    CurrentValue = nullptr;
     return;
   }
   if (Action & PSK_Push)