1 files changed, 62 insertions, 25 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
index 0478c7382f2..1e116dddafa 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -911,7 +911,7 @@ void SelectionDAGISel::DoInstructionSelection() {
 
 /// PrepareEHLandingPad - Emit an EH_LABEL, set up live-in registers, and
 /// do other setup for EH landing-pad blocks.
-bool SelectionDAGISel::PrepareEHLandingPad() {
+void SelectionDAGISel::PrepareEHLandingPad() {
   MachineBasicBlock *MBB = FuncInfo->MBB;
 
   const TargetRegisterClass *PtrRC = TLI->getRegClassFor(TLI->getPointerTy());
@@ -937,28 +937,70 @@ bool SelectionDAGISel::PrepareEHLandingPad() {
 
   if (isMSVCEHPersonality(Personality)) {
     SmallVector<MachineBasicBlock *, 4> ClauseBBs;
-    const IntrinsicInst *ActionsCall =
+    const IntrinsicInst *Actions =
         dyn_cast<IntrinsicInst>(LLVMBB->getFirstInsertionPt());
     // Get all invoke BBs that unwind to this landingpad.
     SmallVector<MachineBasicBlock *, 4> InvokeBBs(MBB->pred_begin(),
                                                   MBB->pred_end());
-    if (!ActionsCall || ActionsCall->getIntrinsicID() != Intrinsic::eh_actions) {
-      assert(isa<UnreachableInst>(LLVMBB->getFirstInsertionPt()) &&
-             "found landingpad without unreachable or llvm.eh.actions");
-      return false;
-    }
+    if (Actions && Actions->getIntrinsicID() == Intrinsic::eh_actions) {
+      // If this is a call to llvm.eh.actions followed by indirectbr, then we've
+      // run WinEHPrepare, and we should remove this block from the machine CFG.
+      // Mark the targets of the indirectbr as landingpads instead.
+      for (const BasicBlock *LLVMSucc : successors(LLVMBB)) {
+        MachineBasicBlock *ClauseBB = FuncInfo->MBBMap[LLVMSucc];
+        // Add the edge from the invoke to the clause.
+        for (MachineBasicBlock *InvokeBB : InvokeBBs)
+          InvokeBB->addSuccessor(ClauseBB);
+      }
+    } else {
+      // Otherwise, we haven't done the preparation, and we need to invent some
+      // clause basic blocks that branch into the landingpad.
+      // FIXME: Remove this code once SEH preparation works.
+
+      // Make virtual registers and a series of labels that fill in values for
+      // the clauses.
+      auto &RI = MF->getRegInfo();
+      FuncInfo->ExceptionSelectorVirtReg = RI.createVirtualRegister(PtrRC);
+
+      // Emit separate machine basic blocks with separate labels for each clause
+      // before the main landing pad block.
+      MachineInstrBuilder SelectorPHI = BuildMI(
+          *MBB, MBB->begin(), SDB->getCurDebugLoc(),
+          TII->get(TargetOpcode::PHI), FuncInfo->ExceptionSelectorVirtReg);
+      for (unsigned I = 0, E = LPadInst->getNumClauses(); I != E; ++I) {
+        // Skip filter clauses, we can't implement them.
+        if (LPadInst->isFilter(I))
+          continue;
+
+        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);
 
-    // If this is a call to llvm.eh.actions followed by indirectbr, then we've
-    // run WinEHPrepare, and we should remove this block from the machine CFG.
-    // Mark the targets of the indirectbr as landingpads instead.
-    for (const BasicBlock *LLVMSucc : successors(LLVMBB)) {
-      MachineBasicBlock *ClauseBB = FuncInfo->MBBMap[LLVMSucc];
-      // 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();
+        // 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.
@@ -975,9 +1017,7 @@ bool SelectionDAGISel::PrepareEHLandingPad() {
       WinEHFuncInfo &FI = MF->getMMI().getWinEHFuncInfo(MF->getFunction());
       MF->getMMI().addWinEHState(MBB, FI.LandingPadStateMap[LPadInst]);
     }
-
-    // Don't select instructions for landing pads using llvm.eh.actions.
-    return false;
+    return;
   }
 
   // Mark exception register as live in.
@@ -987,8 +1027,6 @@ bool SelectionDAGISel::PrepareEHLandingPad() {
   // Mark exception selector register as live in.
   if (unsigned Reg = TLI->getExceptionSelectorRegister())
     FuncInfo->ExceptionSelectorVirtReg = MBB->addLiveIn(Reg, PtrRC);
-
-  return true;
 }
 
 /// isFoldedOrDeadInstruction - Return true if the specified instruction is
@@ -1159,8 +1197,7 @@ void SelectionDAGISel::SelectAllBasicBlocks(const Function &Fn) {
     FuncInfo->ExceptionPointerVirtReg = 0;
     FuncInfo->ExceptionSelectorVirtReg = 0;
     if (LLVMBB->isLandingPad())
-      if (!PrepareEHLandingPad())
-        continue;
+      PrepareEHLandingPad();
 
     // Before doing SelectionDAG ISel, see if FastISel has been requested.
     if (FastIS) {