From 1deef27b0ad538e5017675cf1e085002973bbbb2 Mon Sep 17 00:00:00 2001
From: Evan Cheng <evan.cheng@apple.com>
Date: Thu, 29 Apr 2010 00:59:34 +0000
Subject: [PATCH] Check Reg against zero.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102573 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp | 2 +-
 lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp    | 2 ++
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index 43e6b1bc8a4..254a6543ffd 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -3699,7 +3699,7 @@ SelectionDAGBuilder::EmitFuncArgumentDbgValue(const DbgValueInst &DI,
   unsigned Reg = 0;
   if (N.getOpcode() == ISD::CopyFromReg) {
     Reg = cast<RegisterSDNode>(N.getOperand(1))->getReg();
-    if (TargetRegisterInfo::isVirtualRegister(Reg)) {
+    if (Reg && TargetRegisterInfo::isVirtualRegister(Reg)) {
       MachineRegisterInfo &RegInfo = MF.getRegInfo();
       unsigned PR = RegInfo.getLiveInPhysReg(Reg);
       if (PR)
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
index adb321d929c..88245de0130 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -222,6 +222,8 @@ bool SelectionDAGISel::runOnMachineFunction(MachineFunction &mf) {
   for (unsigned i = 0, e = FuncInfo->ArgDbgValues.size(); i != e; ++i) {
     MachineInstr *MI = FuncInfo->ArgDbgValues[e-i-1];
     unsigned Reg = MI->getOperand(0).getReg();
+    if (!Reg)
+      continue;
     if (TargetRegisterInfo::isPhysicalRegister(Reg))
       EntryMBB->insert(EntryMBB->begin(), MI);
     else {
-- 
2.34.1