Remap frame variables for native Windows exception handling.

Differential Revision: http://reviews.llvm.org/D7770



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230249 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/Transforms/Utils/Cloning.h

@@ -153,6 +153,9 @@ public:
   virtual CloningAction handleInstruction(ValueToValueMapTy &VMap,
                                           const Instruction *Inst,
                                           BasicBlock *NewBB) = 0;
+
+  virtual ValueMapTypeRemapper *getTypeRemapper() { return nullptr; }
+  virtual ValueMaterializer *getValueMaterializer() { return nullptr; }
 };
 
 void CloneAndPruneIntoFromInst(Function *NewFunc, const Function *OldFunc,

lib/CodeGen/WinEHPrepare.cpp

@@ -15,6 +15,8 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/CodeGen/Passes.h"
+#include "llvm/ADT/MapVector.h"
+#include "llvm/ADT/TinyPtrVector.h"
 #include "llvm/Analysis/LibCallSemantics.h"
 #include "llvm/IR/Function.h"
 #include "llvm/IR/IRBuilder.h"
@@ -33,6 +35,19 @@ using namespace llvm::PatternMatch;
 #define DEBUG_TYPE "winehprepare"
 
 namespace {
+
+struct HandlerAllocas {
+  TinyPtrVector<AllocaInst *> Allocas;
+  int ParentFrameAllocationIndex;
+};
+
+// This map is used to model frame variable usage during outlining, to
+// construct a structure type to hold the frame variables in a frame
+// allocation block, and to remap the frame variable allocas (including
+// spill locations as needed) to GEPs that get the variable from the
+// frame allocation structure.
+typedef MapVector<AllocaInst *, HandlerAllocas> FrameVarInfoMap;
+
 class WinEHPrepare : public FunctionPass {
   std::unique_ptr<FunctionPass> DwarfPrepare;
 
@@ -55,13 +70,30 @@ private:
   bool prepareCPPEHHandlers(Function &F,
                             SmallVectorImpl<LandingPadInst *> &LPads);
   bool outlineCatchHandler(Function *SrcFn, Constant *SelectorType,
-                           LandingPadInst *LPad, StructType *EHDataStructTy);
+                           LandingPadInst *LPad, CallInst *&EHAlloc,
+                           AllocaInst *&EHObjPtr, FrameVarInfoMap &VarInfo);
+};
+
+class WinEHFrameVariableMaterializer : public ValueMaterializer {
+public:
+  WinEHFrameVariableMaterializer(Function *OutlinedFn,
+                                 FrameVarInfoMap &FrameVarInfo);
+  ~WinEHFrameVariableMaterializer() {}
+
+  virtual Value *materializeValueFor(Value *V) override;
+
+private:
+  Function *OutlinedFn;
+  FrameVarInfoMap &FrameVarInfo;
+  IRBuilder<> Builder;
 };
 
 class WinEHCatchDirector : public CloningDirector {
 public:
-  WinEHCatchDirector(LandingPadInst *LPI, Value *Selector, Value *EHObj)
+  WinEHCatchDirector(LandingPadInst *LPI, Function *CatchFn, Value *Selector,
+                     Value *EHObj, FrameVarInfoMap &VarInfo)
       : LPI(LPI), CurrentSelector(Selector->stripPointerCasts()), EHObj(EHObj),
+        Materializer(CatchFn, VarInfo),
         SelectorIDType(Type::getInt32Ty(LPI->getContext())),
         Int8PtrType(Type::getInt8PtrTy(LPI->getContext())) {}
 
@@ -69,10 +101,13 @@ public:
                                   const Instruction *Inst,
                                   BasicBlock *NewBB) override;
 
+  ValueMaterializer *getValueMaterializer() override { return &Materializer; }
+
 private:
   LandingPadInst *LPI;
   Value *CurrentSelector;
   Value *EHObj;
+  WinEHFrameVariableMaterializer Materializer;
   Type *SelectorIDType;
   Type *Int8PtrType;
 
@@ -145,14 +180,13 @@ void WinEHPrepare::getAnalysisUsage(AnalysisUsage &AU) const {
 
 bool WinEHPrepare::prepareCPPEHHandlers(
     Function &F, SmallVectorImpl<LandingPadInst *> &LPads) {
-  // FIXME: Find all frame variable references in the handlers
-  //        to populate the structure elements.
-  SmallVector<Type *, 2> AllocStructTys;
-  AllocStructTys.push_back(Type::getInt32Ty(F.getContext()));   // EH state
-  AllocStructTys.push_back(Type::getInt8PtrTy(F.getContext())); // EH object
-  StructType *EHDataStructTy =
-      StructType::create(F.getContext(), AllocStructTys, 
-                         "struct." + F.getName().str() + ".ehdata");
+  // These containers are used to re-map frame variables that are used in
+  // outlined catch and cleanup handlers.  They will be populated as the
+  // handlers are outlined.
+  FrameVarInfoMap FrameVarInfo;
+  SmallVector<CallInst *, 4> HandlerAllocs;
+  SmallVector<AllocaInst *, 4> HandlerEHObjPtrs;
+
   bool HandlersOutlined = false;
 
   for (LandingPadInst *LPad : LPads) {
@@ -175,18 +209,174 @@ bool WinEHPrepare::prepareCPPEHHandlers(
 
     for (unsigned Idx = 0, NumClauses = LPad->getNumClauses(); Idx < NumClauses;
          ++Idx) {
-      if (LPad->isCatch(Idx))
-        HandlersOutlined =
-            outlineCatchHandler(&F, LPad->getClause(Idx), LPad, EHDataStructTy);
-    } // End for each clause
-  }   // End for each landingpad
+      if (LPad->isCatch(Idx)) {
+        // Create a new instance of the handler data structure in the
+        // HandlerData vector.
+        CallInst *EHAlloc = nullptr;
+        AllocaInst *EHObjPtr = nullptr;
+        bool Outlined = outlineCatchHandler(&F, LPad->getClause(Idx), LPad,
+                                            EHAlloc, EHObjPtr, FrameVarInfo);
+        if (Outlined) {
+          HandlersOutlined = true;
+          // These values must be resolved after all handlers have been
+          // outlined.
+          if (EHAlloc)
+            HandlerAllocs.push_back(EHAlloc);
+          if (EHObjPtr)
+            HandlerEHObjPtrs.push_back(EHObjPtr);
+        }
+      } // End if (isCatch)
+    }   // End for each clause
+  }     // End for each landingpad
+
+  // If nothing got outlined, there is no more processing to be done.
+  if (!HandlersOutlined)
+    return false;
+
+  // FIXME: We will replace the landingpad bodies with llvm.eh.actions
+  //        calls and indirect branches here and then delete blocks
+  //        which are no longer reachable.  That will get rid of the
+  //        handlers that we have outlined.  There is code below
+  //        that looks for allocas with no uses in the parent function.
+  //        That will only happen after the pruning is implemented.
+
+  // Remap the frame variables.
+  SmallVector<Type *, 2> StructTys;
+  StructTys.push_back(Type::getInt32Ty(F.getContext()));   // EH state
+  StructTys.push_back(Type::getInt8PtrTy(F.getContext())); // EH object
+
+  // Start the index at two since we always have the above fields at 0 and 1.
+  int Idx = 2;
+
+  // FIXME: Sort the FrameVarInfo vector by the ParentAlloca size and alignment
+  //        and add padding as necessary to provide the proper alignment.
+
+  // Map the alloca instructions to the corresponding index in the
+  // frame allocation structure.  If any alloca is used only in a single
+  // handler and is not used in the parent frame after outlining, it will
+  // be assigned an index of -1, meaning the handler can keep its
+  // "temporary" alloca and the original alloca can be erased from the
+  // parent function.  If we later encounter this alloca in a second
+  // handler, we will assign it a place in the frame allocation structure
+  // at that time.  Since the instruction replacement doesn't happen until
+  // all the entries in the HandlerData have been processed this isn't a
+  // problem.
+  for (auto &VarInfoEntry : FrameVarInfo) {
+    AllocaInst *ParentAlloca = VarInfoEntry.first;
+    HandlerAllocas &AllocaInfo = VarInfoEntry.second;
+
+    // If the instruction still has uses in the parent function or if it is
+    // referenced by more than one handler, add it to the frame allocation
+    // structure.
+    if (ParentAlloca->getNumUses() != 0 || AllocaInfo.Allocas.size() > 1) {
+      Type *VarTy = ParentAlloca->getAllocatedType();
+      StructTys.push_back(VarTy);
+      AllocaInfo.ParentFrameAllocationIndex = Idx++;
+    } else {
+      // If the variable is not used in the parent frame and it is only used
+      // in one handler, the alloca can be removed from the parent frame
+      // and the handler will keep its "temporary" alloca to define the value.
+      // An element index of -1 is used to indicate this condition.
+      AllocaInfo.ParentFrameAllocationIndex = -1;
+    }
+  }
+
+  // Having filled the StructTys vector and assigned an index to each element,
+  // we can now create the structure.
+  StructType *EHDataStructTy = StructType::create(
+      F.getContext(), StructTys, "struct." + F.getName().str() + ".ehdata");
+  IRBuilder<> Builder(F.getParent()->getContext());
+
+  // Create a frame allocation.
+  Module *M = F.getParent();
+  LLVMContext &Context = M->getContext();
+  BasicBlock *Entry = &F.getEntryBlock();
+  Builder.SetInsertPoint(Entry->getFirstInsertionPt());
+  Function *FrameAllocFn =
+      Intrinsic::getDeclaration(M, Intrinsic::frameallocate);
+  uint64_t EHAllocSize = M->getDataLayout()->getTypeAllocSize(EHDataStructTy);
+  Value *FrameAllocArgs[] = {
+      ConstantInt::get(Type::getInt32Ty(Context), EHAllocSize)};
+  CallInst *FrameAlloc =
+      Builder.CreateCall(FrameAllocFn, FrameAllocArgs, "frame.alloc");
+
+  Value *FrameEHData = Builder.CreateBitCast(
+      FrameAlloc, EHDataStructTy->getPointerTo(), "eh.data");
+
+  // Now visit each handler that is using the structure and bitcast its EHAlloc
+  // value to be a pointer to the frame alloc structure.
+  DenseMap<Function *, Value *> EHDataMap;
+  for (CallInst *EHAlloc : HandlerAllocs) {
+    // The EHAlloc has no uses at this time, so we need to just insert the
+    // cast before the next instruction. There is always a next instruction.
+    BasicBlock::iterator II = EHAlloc;
+    ++II;
+    Builder.SetInsertPoint(cast<Instruction>(II));
+    Value *EHData = Builder.CreateBitCast(
+        EHAlloc, EHDataStructTy->getPointerTo(), "eh.data");
+    EHDataMap[EHAlloc->getParent()->getParent()] = EHData;
+  }
+
+  // Next, replace the place-holder EHObjPtr allocas with GEP instructions
+  // that pull the EHObjPtr from the frame alloc structure
+  for (AllocaInst *EHObjPtr : HandlerEHObjPtrs) {
+    Value *EHData = EHDataMap[EHObjPtr->getParent()->getParent()];
+    Value *ElementPtr = Builder.CreateConstInBoundsGEP2_32(EHData, 0, 1);
+    EHObjPtr->replaceAllUsesWith(ElementPtr);
+    EHObjPtr->removeFromParent();
+    ElementPtr->takeName(EHObjPtr);
+    delete EHObjPtr;
+  }
+
+  // Finally, replace all of the temporary allocas for frame variables used in
+  // the outlined handlers and the original frame allocas with GEP instructions
+  // that get the equivalent pointer from the frame allocation struct.
+  for (auto &VarInfoEntry : FrameVarInfo) {
+    AllocaInst *ParentAlloca = VarInfoEntry.first;
+    HandlerAllocas &AllocaInfo = VarInfoEntry.second;
+    int Idx = AllocaInfo.ParentFrameAllocationIndex;
+
+    // If we have an index of -1 for this instruction, it means it isn't used
+    // outside of this handler.  In that case, we just keep the "temporary"
+    // alloca in the handler and erase the original alloca from the parent.
+    if (Idx == -1) {
+      ParentAlloca->eraseFromParent();
+    } else {
+      // Otherwise, we replace the parent alloca and all outlined allocas
+      // which map to it with GEP instructions.
+
+      // First replace the original alloca.
+      Builder.SetInsertPoint(ParentAlloca);
+      Builder.SetCurrentDebugLocation(ParentAlloca->getDebugLoc());
+      Value *ElementPtr =
+          Builder.CreateConstInBoundsGEP2_32(FrameEHData, 0, Idx);
+      ParentAlloca->replaceAllUsesWith(ElementPtr);
+      ParentAlloca->removeFromParent();
+      ElementPtr->takeName(ParentAlloca);
+      delete ParentAlloca;
+
+      // Next replace all outlined allocas that are mapped to it.
+      for (AllocaInst *TempAlloca : AllocaInfo.Allocas) {
+        Value *EHData = EHDataMap[TempAlloca->getParent()->getParent()];
+        // FIXME: Sink this GEP into the blocks where it is used.
+        Builder.SetInsertPoint(TempAlloca);
+        Builder.SetCurrentDebugLocation(TempAlloca->getDebugLoc());
+        ElementPtr = Builder.CreateConstInBoundsGEP2_32(EHData, 0, Idx);
+        TempAlloca->replaceAllUsesWith(ElementPtr);
+        TempAlloca->removeFromParent();
+        ElementPtr->takeName(TempAlloca);
+        delete TempAlloca;
+      }
+    } // end else of if (Idx == -1)
+  }   // End for each FrameVarInfo entry.
 
   return HandlersOutlined;
 }
 
 bool WinEHPrepare::outlineCatchHandler(Function *SrcFn, Constant *SelectorType,
-                                       LandingPadInst *LPad,
-                                       StructType *EHDataStructTy) {
+                                       LandingPadInst *LPad, CallInst *&EHAlloc,
+                                       AllocaInst *&EHObjPtr,
+                                       FrameVarInfoMap &VarInfo) {
   Module *M = SrcFn->getParent();
   LLVMContext &Context = M->getContext();
 
@@ -221,12 +411,11 @@ bool WinEHPrepare::outlineCatchHandler(Function *SrcFn, Constant *SelectorType,
       Intrinsic::getDeclaration(M, Intrinsic::framerecover);
   Value *RecoverArgs[] = {Builder.CreateBitCast(SrcFn, Int8PtrType, ""),
                           &(CatchHandler->getArgumentList().back())};
-  CallInst *EHAlloc =
-      Builder.CreateCall(RecoverFrameFn, RecoverArgs, "eh.alloc");
-  Value *EHData =
-      Builder.CreateBitCast(EHAlloc, EHDataStructTy->getPointerTo(), "ehdata");
-  Value *EHObjPtr =
-      Builder.CreateConstInBoundsGEP2_32(EHData, 0, 1, "eh.obj.ptr");
+  EHAlloc = Builder.CreateCall(RecoverFrameFn, RecoverArgs, "eh.alloc");
+
+  // This alloca is only temporary.  We'll be replacing it once we know all the
+  // frame variables that need to go in the frame allocation structure.
+  EHObjPtr = Builder.CreateAlloca(Int8PtrType, 0, "eh.obj.ptr");
 
   // This will give us a raw pointer to the exception object, which
   // corresponds to the formal parameter of the catch statement.  If the
@@ -240,7 +429,7 @@ bool WinEHPrepare::outlineCatchHandler(Function *SrcFn, Constant *SelectorType,
 
   // FIXME: Map other values referenced in the filter handler.
 
-  WinEHCatchDirector Director(LPad, SelectorType, EHObj);
+  WinEHCatchDirector Director(LPad, CatchHandler, SelectorType, EHObj, VarInfo);
 
   SmallVector<ReturnInst *, 8> Returns;
   ClonedCodeInfo InlinedFunctionInfo;
@@ -271,9 +460,11 @@ CloningDirector::CloningAction WinEHCatchDirector::handleInstruction(
              "Unexpected operation: extracting an unknown landing pad element");
 
       if (*(Extract->idx_begin()) == 0) {
-        // Element 0 doesn't directly corresponds to anything in the WinEH scheme.
+        // Element 0 doesn't directly corresponds to anything in the WinEH
+        // scheme.
         // It will be stored to a memory location, then later loaded and finally
-        // the loaded value will be used as the argument to an llvm.eh.begincatch
+        // the loaded value will be used as the argument to an
+        // llvm.eh.begincatch
         // call.  We're tracking it here so that we can skip the store and load.
         ExtractedEHPtr = Inst;
       } else {
@@ -362,10 +553,10 @@ CloningDirector::CloningAction WinEHCatchDirector::handleInstruction(
     const BranchInst *Branch = dyn_cast<BranchInst>(Terminator);
     assert(Branch && Branch->isUnconditional());
     assert(std::next(BasicBlock::const_iterator(IntrinCall)) ==
-            BasicBlock::const_iterator(Branch));
+           BasicBlock::const_iterator(Branch));
 
     ReturnInst::Create(NewBB->getContext(),
-                        BlockAddress::get(Branch->getSuccessor(0)), NewBB);
+                       BlockAddress::get(Branch->getSuccessor(0)), NewBB);
 
     // We just added a terminator to the cloned block.
     // Tell the caller to stop processing the current basic block so that
@@ -388,3 +579,49 @@ CloningDirector::CloningAction WinEHCatchDirector::handleInstruction(
   // Continue with the default cloning behavior.
   return CloningDirector::CloneInstruction;
 }
+
+WinEHFrameVariableMaterializer::WinEHFrameVariableMaterializer(
+    Function *OutlinedFn, FrameVarInfoMap &FrameVarInfo)
+    : OutlinedFn(OutlinedFn), FrameVarInfo(FrameVarInfo),
+      Builder(OutlinedFn->getContext()) {
+  Builder.SetInsertPoint(&OutlinedFn->getEntryBlock());
+  // FIXME: Do something with the FrameVarMapped so that it is shared across the
+  // function.
+}
+
+Value *WinEHFrameVariableMaterializer::materializeValueFor(Value *V) {
+  // If we're asked to materialize an alloca variable, we temporarily
+  // create a matching alloca in the outlined function.  When all the
+  // outlining is complete, we'll collect these into a structure and
+  // replace these temporary allocas with GEPs referencing the frame
+  // allocation block.
+  if (auto *AV = dyn_cast<AllocaInst>(V)) {
+    AllocaInst *NewAlloca = Builder.CreateAlloca(
+        AV->getAllocatedType(), AV->getArraySize(), AV->getName());
+    FrameVarInfo[AV].Allocas.push_back(NewAlloca);
+    return NewAlloca;
+  }
+
+// FIXME: Do PHI nodes need special handling?
+
+// FIXME: Are there other cases we can handle better?  GEP, ExtractValue, etc.
+
+// FIXME: This doesn't work during cloning because it finds an instruction
+//        in the use list that isn't yet part of a basic block.
+#if 0
+  // If we're asked to remap some other instruction, we'll need to
+  // spill it to an alloca variable in the parent function and add a
+  // temporary alloca in the outlined function to be processed as
+  // described above.
+  Instruction *Inst = dyn_cast<Instruction>(V);
+  if (Inst) {
+    AllocaInst *Spill = DemoteRegToStack(*Inst, true);
+    AllocaInst *NewAlloca = Builder.CreateAlloca(Spill->getAllocatedType(),
+                                                 Spill->getArraySize());
+    FrameVarMap[AV] = NewAlloca;
+    return NewAlloca;
+  }
+#endif
+
+  return nullptr;
+}

lib/Transforms/Utils/CloneFunction.cpp

@@ -261,6 +261,8 @@ namespace {
     ClonedCodeInfo *CodeInfo;
     const DataLayout *DL;
     CloningDirector *Director;
+    ValueMapTypeRemapper *TypeMapper;
+    ValueMaterializer *Materializer;
 
   public:
     PruningFunctionCloner(Function *newFunc, const Function *oldFunc,
@@ -274,6 +276,14 @@ namespace {
       VMap(valueMap), ModuleLevelChanges(moduleLevelChanges),
       NameSuffix(nameSuffix), CodeInfo(codeInfo), DL(DL),
       Director(Director) {
+      // These are optional components.  The Director may return null.
+      if (Director) {
+        TypeMapper = Director->getTypeRemapper();
+        Materializer = Director->getValueMaterializer();
+      } else {
+        TypeMapper = nullptr;
+        Materializer = nullptr;
+      }
     }
 
     /// CloneBlock - The specified block is found to be reachable, clone it and
@@ -344,7 +354,8 @@ void PruningFunctionCloner::CloneBlock(const BasicBlock *BB,
     // nodes for which we defer processing until we update the CFG.
     if (!isa<PHINode>(NewInst)) {
       RemapInstruction(NewInst, VMap,
-                       ModuleLevelChanges ? RF_None : RF_NoModuleLevelChanges);
+                       ModuleLevelChanges ? RF_None : RF_NoModuleLevelChanges,
+                       TypeMapper, Materializer);
 
       // If we can simplify this instruction to some other value, simply add
       // a mapping to that value rather than inserting a new instruction into
@@ -459,6 +470,14 @@ void llvm::CloneAndPruneIntoFromInst(Function *NewFunc, const Function *OldFunc,
                                      CloningDirector *Director) {
   assert(NameSuffix && "NameSuffix cannot be null!");
 
+  ValueMapTypeRemapper *TypeMapper = nullptr;
+  ValueMaterializer *Materializer = nullptr;
+
+  if (Director) {
+    TypeMapper = Director->getTypeRemapper();
+    Materializer = Director->getValueMaterializer();
+  }
+
 #ifndef NDEBUG
   // If the cloning starts at the begining of the function, verify that
   // the function arguments are mapped.
@@ -513,7 +532,8 @@ void llvm::CloneAndPruneIntoFromInst(Function *NewFunc, const Function *OldFunc,
     // Finally, remap the terminator instructions, as those can't be remapped
     // until all BBs are mapped.
     RemapInstruction(NewBB->getTerminator(), VMap,
-                     ModuleLevelChanges ? RF_None : RF_NoModuleLevelChanges);
+                     ModuleLevelChanges ? RF_None : RF_NoModuleLevelChanges,
+                     TypeMapper, Materializer);
   }
   
   // Defer PHI resolution until rest of function is resolved, PHI resolution

test/CodeGen/X86/cppeh-catch-all.ll

@@ -55,8 +55,8 @@ try.cont:                                         ; preds = %invoke.cont2, %invo
 ; CHECK: define i8* @_Z4testv.catch(i8*, i8*) {
 ; CHECK: catch.entry:
 ; CHECK:   %eh.alloc = call i8* @llvm.framerecover(i8* bitcast (void ()* @_Z4testv to i8*), i8* %1)
-; CHECK:   %ehdata = bitcast i8* %eh.alloc to %struct._Z4testv.ehdata*
-; CHECK:   %eh.obj.ptr = getelementptr inbounds %struct._Z4testv.ehdata* %ehdata, i32 0, i32 1
+; CHECK:   %eh.data = bitcast i8* %eh.alloc to %struct._Z4testv.ehdata*
+; CHECK:   %eh.obj.ptr = getelementptr inbounds %struct._Z4testv.ehdata* %eh.data, i32 0, i32 1
 ; CHECK:   %eh.obj = load i8** %eh.obj.ptr
 ; CHECK:   call void @_Z16handle_exceptionv()
 ; CHECK:   ret i8* blockaddress(@_Z4testv, %try.cont)

test/CodeGen/X86/cppeh-catch-scalar.ll

@@ -6,8 +6,8 @@
 ; {
 ;   try {
 ;     may_throw();
-;   } catch (int) {
-;     handle_int();
+;   } catch (int i) {
+;     handle_int(i);
 ;   }
 ; }
 ;
@@ -18,13 +18,27 @@
 target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
 target triple = "x86_64-pc-windows-msvc"
 
+; This is the structure that will get created for the frame allocation.
+; CHECK: %struct._Z4testv.ehdata = type { i32, i8*, i32 }
+
 @_ZTIi = external constant i8*
 
+; The function entry will be rewritten like this.
+; CHECK: define void @_Z4testv() #0 {
+; CHECK: entry:
+; CHECK:   %frame.alloc = call i8* @llvm.frameallocate(i32 24)
+; CHECK:   %eh.data = bitcast i8* %frame.alloc to %struct._Z4testv.ehdata*
+; CHECK:   %exn.slot = alloca i8*
+; CHECK:   %ehselector.slot = alloca i32
+; CHECK-NOT:  %i = alloca i32, align 4
+; CHECK:  %i = getelementptr inbounds %struct._Z4testv.ehdata* %eh.data, i32 0, i32 2
+
 ; Function Attrs: uwtable
 define void @_Z4testv() #0 {
 entry:
   %exn.slot = alloca i8*
   %ehselector.slot = alloca i32
+  %i = alloca i32, align 4
   invoke void @_Z9may_throwv()
           to label %invoke.cont unwind label %lpad
 
@@ -50,7 +64,10 @@ catch:                                            ; preds = %catch.dispatch
   %exn11 = load i8** %exn.slot
   %4 = call i8* @llvm.eh.begincatch(i8* %exn11) #3
   %5 = bitcast i8* %4 to i32*
-  call void @_Z10handle_intv()
+  %6 = load i32* %5, align 4
+  store i32 %6, i32* %i, align 4
+  %7 = load i32* %i, align 4
+  call void @_Z10handle_inti(i32 %7)
   br label %invoke.cont2
 
 invoke.cont2:                                     ; preds = %catch
@@ -71,11 +88,15 @@ eh.resume:                                        ; preds = %catch.dispatch
 ; CHECK: define i8* @_Z4testv.catch(i8*, i8*) {
 ; CHECK: catch.entry:
 ; CHECK:   %eh.alloc = call i8* @llvm.framerecover(i8* bitcast (void ()* @_Z4testv to i8*), i8* %1)
-; CHECK:   %ehdata = bitcast i8* %eh.alloc to %struct._Z4testv.ehdata*
-; CHECK:   %eh.obj.ptr = getelementptr inbounds %struct._Z4testv.ehdata* %ehdata, i32 0, i32 1
+; CHECK:   %eh.data = bitcast i8* %eh.alloc to %struct._Z4testv.ehdata*
+; CHECK:   %eh.obj.ptr = getelementptr inbounds %struct._Z4testv.ehdata* %eh.data, i32 0, i32 1
 ; CHECK:   %eh.obj = load i8** %eh.obj.ptr
+; CHECK:   %i = getelementptr inbounds %struct._Z4testv.ehdata* %eh.data, i32 0, i32 2
 ; CHECK:   %2 = bitcast i8* %eh.obj to i32*
-; CHECK:   call void @_Z10handle_intv()
+; CHECK:   %3 = load i32* %2, align 4
+; CHECK:   store i32 %3, i32* %i, align 4
+; CHECK:   %4 = load i32* %i, align 4
+; CHECK:   call void @_Z10handle_inti(i32 %4)
 ; CHECK:   ret i8* blockaddress(@_Z4testv, %try.cont)
 ; CHECK: }
 
@@ -90,7 +111,7 @@ declare i8* @llvm.eh.begincatch(i8*)
 
 declare void @llvm.eh.endcatch()
 
-declare void @_Z10handle_intv() #1
+declare void @_Z10handle_inti(i32) #1
 
 attributes #0 = { uwtable "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
 attributes #1 = { "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }