[WinEH] Handle nested landing pads in outlined catch handlers

Differential Revision: http://reviews.llvm.org/D8596



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234041 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/CodeGen/WinEHFuncInfo.h

@@ -23,6 +23,7 @@ class BasicBlock;
 class Constant;
 class Function;
 class GlobalValue;
+class IntrinsicInst;
 class LandingPadInst;
 class MCSymbol;
 class Value;
@@ -58,7 +59,8 @@ class CatchHandler : public ActionHandler {
 public:
   CatchHandler(BasicBlock *BB, Constant *Selector, BasicBlock *NextBB)
       : ActionHandler(BB, ActionType::Catch), Selector(Selector),
-        NextBB(NextBB), ExceptionObjectVar(nullptr) {}
+      NextBB(NextBB), ExceptionObjectVar(nullptr),
+      ExceptionObjectIndex(-1) {}
 
   // Method for support type inquiry through isa, cast, and dyn_cast:
   static inline bool classof(const ActionHandler *H) {
@@ -72,14 +74,24 @@ class CatchHandler : public ActionHandler {
   TinyPtrVector<BasicBlock *> &getReturnTargets() { return ReturnTargets; }
 
   void setExceptionVar(const Value *Val) { ExceptionObjectVar = Val; }
+  void setExceptionVarIndex(int Index) { ExceptionObjectIndex = Index;  }
   void setReturnTargets(TinyPtrVector<BasicBlock *> &Targets) {
     ReturnTargets = Targets;
   }
 
 private:
   Constant *Selector;
   BasicBlock *NextBB;
+  // While catch handlers are being outlined the ExceptionObjectVar field will
+  // be populated with the instruction in the parent frame that corresponds
+  // to the exception object (or nullptr if the catch does not use an
+  // exception object) and the ExceptionObjectIndex field will be -1.
+  // When the parseEHActions function is called to populate a vector of
+  // instances of this class, the ExceptionObjectVar field will be nullptr
+  // and the ExceptionObjectIndex will be the index of the exception object in
+  // the parent function's frameescape block.
   const Value *ExceptionObjectVar;
+  int ExceptionObjectIndex;
   TinyPtrVector<BasicBlock *> ReturnTargets;
 };
 
@@ -93,6 +105,10 @@ class CleanupHandler : public ActionHandler {
   }
 };
 
+void parseEHActions(const IntrinsicInst *II,
+  SmallVectorImpl<ActionHandler *> &Actions);
+
+
 // The following structs respresent the .xdata for functions using C++
 // exceptions on Windows.
 

lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp

@@ -94,8 +94,6 @@ struct WinEHNumbering {
     return HandlerStack.empty() ? -1 : HandlerStack.back()->getEHState();
   }
 
-  void parseEHActions(const IntrinsicInst *II,
-                      SmallVectorImpl<ActionHandler *> &Actions);
   void createUnwindMapEntry(int ToState, ActionHandler *AH);
   void createTryBlockMapEntry(int TryLow, int TryHigh,
                               ArrayRef<CatchHandler *> Handlers);
@@ -287,32 +285,6 @@ void FunctionLoweringInfo::set(const Function &fn, MachineFunction &mf,
   }
 }
 
-void WinEHNumbering::parseEHActions(const IntrinsicInst *II,
-                                    SmallVectorImpl<ActionHandler *> &Actions) {
-  for (unsigned I = 0, E = II->getNumArgOperands(); I != E;) {
-    uint64_t ActionKind =
-        cast<ConstantInt>(II->getArgOperand(I))->getZExtValue();
-    if (ActionKind == /*catch=*/1) {
-      auto *Selector = cast<Constant>(II->getArgOperand(I + 1));
-      Value *CatchObject = II->getArgOperand(I + 2);
-      Constant *Handler = cast<Constant>(II->getArgOperand(I + 3));
-      I += 4;
-      auto *CH = new CatchHandler(/*BB=*/nullptr, Selector, /*NextBB=*/nullptr);
-      CH->setExceptionVar(CatchObject);
-      CH->setHandlerBlockOrFunc(Handler);
-      Actions.push_back(CH);
-    } else {
-      assert(ActionKind == 0 && "expected a cleanup or a catch action!");
-      Constant *Handler = cast<Constant>(II->getArgOperand(I + 1));
-      I += 2;
-      auto *CH = new CleanupHandler(/*BB=*/nullptr);
-      CH->setHandlerBlockOrFunc(Handler);
-      Actions.push_back(CH);
-    }
-  }
-  std::reverse(Actions.begin(), Actions.end());
-}
-
 void WinEHNumbering::createUnwindMapEntry(int ToState, ActionHandler *AH) {
   WinEHUnwindMapEntry UME;
   UME.ToState = ToState;