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

This reverts commit r267866.

llvm-svn: 267870

1 files changed, 24 insertions, 8 deletions

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)