FastISel support for exception-handling constructs.

 - Move the EH landing-pad code and adjust it so that it works
   with FastISel as well as with SDISel.
 - Add FastISel support for @llvm.eh.exception and
   @llvm.eh.selector.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57539 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 50 insertions, 47 deletions

diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
index 6e9b2885a8..fb5619cc49 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -314,7 +314,7 @@ bool SelectionDAGISel::runOnFunction(Function &Fn) {
       // Mark landing pad.
       FuncInfo->MBBMap[Invoke->getSuccessor(1)]->setIsLandingPad();
 
-  SelectAllBasicBlocks(Fn, MF, MMI);
+  SelectAllBasicBlocks(Fn, MF, MMI, TII);
 
   // If the first basic block in the function has live ins that need to be
   // copied into vregs, emit the copies into the top of the block before
@@ -452,48 +452,6 @@ void SelectionDAGISel::SelectBasicBlock(BasicBlock *LLVMBB,
                                         BasicBlock::iterator End) {
   SDL->setCurrentBasicBlock(BB);
 
-  MachineModuleInfo *MMI = CurDAG->getMachineModuleInfo();
-
-  if (MMI && BB->isLandingPad()) {
-    // Add a label to mark the beginning of the landing pad.  Deletion of the
-    // landing pad can thus be detected via the MachineModuleInfo.
-    unsigned LabelID = MMI->addLandingPad(BB);
-    CurDAG->setRoot(CurDAG->getLabel(ISD::EH_LABEL,
-                                     CurDAG->getEntryNode(), LabelID));
-
-    // Mark exception register as live in.
-    unsigned Reg = TLI.getExceptionAddressRegister();
-    if (Reg) BB->addLiveIn(Reg);
-
-    // Mark exception selector register as live in.
-    Reg = TLI.getExceptionSelectorRegister();
-    if (Reg) BB->addLiveIn(Reg);
-
-    // FIXME: Hack around an exception handling flaw (PR1508): the personality
-    // function and list of typeids logically belong to the invoke (or, if you
-    // like, the basic block containing the invoke), and need to be associated
-    // with it in the dwarf exception handling tables.  Currently however the
-    // information is provided by an intrinsic (eh.selector) that can be moved
-    // to unexpected places by the optimizers: if the unwind edge is critical,
-    // then breaking it can result in the intrinsics being in the successor of
-    // the landing pad, not the landing pad itself.  This results in exceptions
-    // not being caught because no typeids are associated with the invoke.
-    // This may not be the only way things can go wrong, but it is the only way
-    // we try to work around for the moment.
-    BranchInst *Br = dyn_cast<BranchInst>(LLVMBB->getTerminator());
-
-    if (Br && Br->isUnconditional()) { // Critical edge?
-      BasicBlock::iterator I, E;
-      for (I = LLVMBB->begin(), E = --LLVMBB->end(); I != E; ++I)
-        if (isa<EHSelectorInst>(I))
-          break;
-
-      if (I == E)
-        // No catch info found - try to extract some from the successor.
-        copyCatchInfo(Br->getSuccessor(0), LLVMBB, MMI, *FuncInfo);
-    }
-  }
-
   // Lower all of the non-terminator instructions.
   for (BasicBlock::iterator I = Begin; I != End; ++I)
     if (!isa<TerminatorInst>(I))
@@ -708,14 +666,19 @@ void SelectionDAGISel::CodeGenAndEmitDAG() {
 }  
 
 void SelectionDAGISel::SelectAllBasicBlocks(Function &Fn, MachineFunction &MF,
-                                            MachineModuleInfo *MMI) {
+                                            MachineModuleInfo *MMI,
+                                            const TargetInstrInfo &TII) {
   // Initialize the Fast-ISel state, if needed.
   FastISel *FastIS = 0;
   if (EnableFastISel)
     FastIS = TLI.createFastISel(*FuncInfo->MF, MMI,
                                 FuncInfo->ValueMap,
                                 FuncInfo->MBBMap,
-                                FuncInfo->StaticAllocaMap);
+                                FuncInfo->StaticAllocaMap
+#ifndef NDEBUG
+                                , FuncInfo->CatchInfoLost
+#endif
+                                );
 
   // Iterate over all basic blocks in the function.
   for (Function::iterator I = Fn.begin(), E = Fn.end(); I != E; ++I) {
@@ -746,9 +709,49 @@ void SelectionDAGISel::SelectAllBasicBlocks(Function &Fn, MachineFunction &MF,
       }
     }
 
+    if (MMI && BB->isLandingPad()) {
+      // Add a label to mark the beginning of the landing pad.  Deletion of the
+      // landing pad can thus be detected via the MachineModuleInfo.
+      unsigned LabelID = MMI->addLandingPad(BB);
+
+      const TargetInstrDesc &II = TII.get(TargetInstrInfo::EH_LABEL);
+      BuildMI(BB, II).addImm(LabelID);
+
+      // Mark exception register as live in.
+      unsigned Reg = TLI.getExceptionAddressRegister();
+      if (Reg) BB->addLiveIn(Reg);
+
+      // Mark exception selector register as live in.
+      Reg = TLI.getExceptionSelectorRegister();
+      if (Reg) BB->addLiveIn(Reg);
+
+      // FIXME: Hack around an exception handling flaw (PR1508): the personality
+      // function and list of typeids logically belong to the invoke (or, if you
+      // like, the basic block containing the invoke), and need to be associated
+      // with it in the dwarf exception handling tables.  Currently however the
+      // information is provided by an intrinsic (eh.selector) that can be moved
+      // to unexpected places by the optimizers: if the unwind edge is critical,
+      // then breaking it can result in the intrinsics being in the successor of
+      // the landing pad, not the landing pad itself.  This results in exceptions
+      // not being caught because no typeids are associated with the invoke.
+      // This may not be the only way things can go wrong, but it is the only way
+      // we try to work around for the moment.
+      BranchInst *Br = dyn_cast<BranchInst>(LLVMBB->getTerminator());
+
+      if (Br && Br->isUnconditional()) { // Critical edge?
+        BasicBlock::iterator I, E;
+        for (I = LLVMBB->begin(), E = --LLVMBB->end(); I != E; ++I)
+          if (isa<EHSelectorInst>(I))
+            break;
+
+        if (I == E)
+          // No catch info found - try to extract some from the successor.
+          copyCatchInfo(Br->getSuccessor(0), LLVMBB, MMI, *FuncInfo);
+      }
+    }
+
     // Before doing SelectionDAG ISel, see if FastISel has been requested.
-    // FastISel doesn't support EH landing pads, which require special handling.
-    if (FastIS && !SuppressFastISel && !BB->isLandingPad()) {
+    if (FastIS && !SuppressFastISel) {
       // Emit code for any incoming arguments. This must happen before
       // beginning FastISel on the entry block.
       if (LLVMBB == &Fn.getEntryBlock()) {