4 files changed, 14 insertions, 10 deletions
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index 97d975e..ee8f272 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -5273,11 +5273,6 @@ void SelectionDAGBuilder::LowerCallTo(ImmutableCallSite CS, SDValue Callee,
       !isInTailCallPosition(CS, CS.getAttributes().getRetAttributes(), TLI))
     isTailCall = false;
 
-  // If there's a possibility that fast-isel has already selected some amount
-  // of the current basic block, don't emit a tail call.
-  if (isTailCall && TM.Options.EnableFastISel)
-    isTailCall = false;
-
   TargetLowering::
   CallLoweringInfo CLI(getRoot(), RetTy, FTy, isTailCall, Callee, Args, DAG,
                        getCurDebugLoc(), CS);
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
index ca25274..c755d72 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -1113,19 +1113,21 @@ void SelectionDAGISel::SelectAllBasicBlocks(const Function &Fn) {
           }
 
           bool HadTailCall = false;
+          MachineBasicBlock::iterator SavedInsertPt = FuncInfo->InsertPt;
           SelectBasicBlock(Inst, BI, HadTailCall);
 
-          // Recompute NumFastIselRemaining as Selection DAG instruction
-          // selection may have handled the call, input args, etc.
-          unsigned RemainingNow = std::distance(Begin, BI);
-          NumFastIselFailures += NumFastIselRemaining - RemainingNow;
-
           // If the call was emitted as a tail call, we're done with the block.
+          // We also need to delete any previously emitted instructions.
           if (HadTailCall) {
+            FastIS->removeDeadCode(SavedInsertPt, FuncInfo->MBB->end());
             --BI;
             break;
           }
 
+          // Recompute NumFastIselRemaining as Selection DAG instruction
+          // selection may have handled the call, input args, etc.
+          unsigned RemainingNow = std::distance(Begin, BI);
+          NumFastIselFailures += NumFastIselRemaining - RemainingNow;
           NumFastIselRemaining = RemainingNow;
           continue;
         }
diff --git a/lib/Target/ARM/ARMFastISel.cpp b/lib/Target/ARM/ARMFastISel.cpp
index 21bb147..c3a5e64 100644
--- a/lib/Target/ARM/ARMFastISel.cpp
+++ b/lib/Target/ARM/ARMFastISel.cpp
@@ -2284,6 +2284,9 @@ bool ARMFastISel::SelectCall(const Instruction *I,
   // Can't handle inline asm.
   if (isa<InlineAsm>(Callee)) return false;
 
+  // Allow SelectionDAG isel to handle tail calls.
+  if (CI->isTailCall()) return false;
+
   // Check the calling convention.
   ImmutableCallSite CS(CI);
   CallingConv::ID CC = CS.getCallingConv();
diff --git a/lib/Target/X86/X86FastISel.cpp b/lib/Target/X86/X86FastISel.cpp
index b26b9d7..3e78b4c 100644
--- a/lib/Target/X86/X86FastISel.cpp
+++ b/lib/Target/X86/X86FastISel.cpp
@@ -1529,6 +1529,10 @@ bool X86FastISel::X86SelectCall(const Instruction *I) {
   if (const IntrinsicInst *II = dyn_cast<IntrinsicInst>(CI))
     return X86VisitIntrinsicCall(*II);
 
+  // Allow SelectionDAG isel to handle tail calls.
+  if (cast<CallInst>(I)->isTailCall())
+    return false;
+
   return DoSelectCall(I, 0);
 }