1 files changed, 63 insertions, 1 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
index 79109b7b8e6..a3f0fa47dd9 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -19,6 +19,7 @@
 #include "llvm/Analysis/AliasAnalysis.h"
 #include "llvm/Analysis/BranchProbabilityInfo.h"
 #include "llvm/Analysis/CFG.h"
+#include "llvm/CodeGen/Analysis.h"
 #include "llvm/CodeGen/FastISel.h"
 #include "llvm/CodeGen/FunctionLoweringInfo.h"
 #include "llvm/CodeGen/GCMetadata.h"
@@ -40,6 +41,7 @@
 #include "llvm/IR/Intrinsics.h"
 #include "llvm/IR/LLVMContext.h"
 #include "llvm/IR/Module.h"
+#include "llvm/MC/MCAsmInfo.h"
 #include "llvm/Support/Compiler.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/ErrorHandling.h"
@@ -892,6 +894,8 @@ void SelectionDAGISel::DoInstructionSelection() {
 void SelectionDAGISel::PrepareEHLandingPad() {
   MachineBasicBlock *MBB = FuncInfo->MBB;
 
+  const TargetRegisterClass *PtrRC = TLI->getRegClassFor(TLI->getPointerTy());
+
   // Add a label to mark the beginning of the landing pad.  Deletion of the
   // landing pad can thus be detected via the MachineModuleInfo.
   MCSymbol *Label = MF->getMMI().addLandingPad(MBB);
@@ -903,8 +907,66 @@ void SelectionDAGISel::PrepareEHLandingPad() {
   BuildMI(*MBB, FuncInfo->InsertPt, SDB->getCurDebugLoc(), II)
     .addSym(Label);
 
+  if (TM.getMCAsmInfo()->getExceptionHandlingType() ==
+      ExceptionHandling::MSVC) {
+    // Make virtual registers and a series of labels that fill in values for the
+    // clauses.
+    auto &RI = MF->getRegInfo();
+    FuncInfo->ExceptionSelectorVirtReg = RI.createVirtualRegister(PtrRC);
+
+    // Get all invoke BBs that will unwind into the clause BBs.
+    SmallVector<MachineBasicBlock *, 4> InvokeBBs(MBB->pred_begin(),
+                                                  MBB->pred_end());
+
+    // Emit separate machine basic blocks with separate labels for each clause
+    // before the main landing pad block.
+    const BasicBlock *LLVMBB = MBB->getBasicBlock();
+    const LandingPadInst *LPadInst = LLVMBB->getLandingPadInst();
+    MachineInstrBuilder SelectorPHI = BuildMI(
+        *MBB, MBB->begin(), SDB->getCurDebugLoc(), TII->get(TargetOpcode::PHI),
+        FuncInfo->ExceptionSelectorVirtReg);
+    for (unsigned I = 0, E = LPadInst->getNumClauses(); I != E; ++I) {
+      MachineBasicBlock *ClauseBB = MF->CreateMachineBasicBlock(LLVMBB);
+      MF->insert(MBB, ClauseBB);
+
+      // Add the edge from the invoke to the clause.
+      for (MachineBasicBlock *InvokeBB : InvokeBBs)
+        InvokeBB->addSuccessor(ClauseBB);
+
+      // Mark the clause as a landing pad or MI passes will delete it.
+      ClauseBB->setIsLandingPad();
+
+      GlobalValue *ClauseGV = ExtractTypeInfo(LPadInst->getClause(I));
+
+      // Start the BB with a label.
+      MCSymbol *ClauseLabel = MF->getMMI().addClauseForLandingPad(MBB);
+      BuildMI(*ClauseBB, ClauseBB->begin(), SDB->getCurDebugLoc(), II)
+          .addSym(ClauseLabel);
+
+      // Construct a simple BB that defines a register with the typeid constant.
+      FuncInfo->MBB = ClauseBB;
+      FuncInfo->InsertPt = ClauseBB->end();
+      unsigned VReg = SDB->visitLandingPadClauseBB(ClauseGV, MBB);
+      CurDAG->setRoot(SDB->getRoot());
+      SDB->clear();
+      CodeGenAndEmitDAG();
+
+      // Add the typeid virtual register to the phi in the main landing pad.
+      SelectorPHI.addReg(VReg).addMBB(ClauseBB);
+    }
+
+    // Remove the edge from the invoke to the lpad.
+    for (MachineBasicBlock *InvokeBB : InvokeBBs)
+      InvokeBB->removeSuccessor(MBB);
+
+    // Restore FuncInfo back to its previous state and select the main landing
+    // pad block.
+    FuncInfo->MBB = MBB;
+    FuncInfo->InsertPt = MBB->end();
+    return;
+  }
+
   // Mark exception register as live in.
-  const TargetRegisterClass *PtrRC = TLI->getRegClassFor(TLI->getPointerTy());
   if (unsigned Reg = TLI->getExceptionPointerRegister())
     FuncInfo->ExceptionPointerVirtReg = MBB->addLiveIn(Reg, PtrRC);