Revert r128045 and r128051, debug info enhancements.

[oota-llvm.git] / lib / CodeGen / LiveDebugVariables.cpp

diff --git a/lib/CodeGen/LiveDebugVariables.cpp b/lib/CodeGen/LiveDebugVariables.cpp
index 900dc0132783764c0a9c6f127479af8f4559a98c..20e997ae377bdb6935959cf3c206548e40686ffa 100644 (file)
--- a/lib/CodeGen/LiveDebugVariables.cpp
+++ b/lib/CodeGen/LiveDebugVariables.cpp
@@ -101,6 +101,10 @@ class UserValue {
   void insertDebugValue(MachineBasicBlock *MBB, SlotIndex Idx, unsigned LocNo,
                         LiveIntervals &LIS, const TargetInstrInfo &TII);
 
+  /// insertDebugKill - Insert an undef DBG_VALUE into MBB at Idx.
+  void insertDebugKill(MachineBasicBlock *MBB, SlotIndex Idx,
+                       LiveIntervals &LIS, const TargetInstrInfo &TII);
+
 public:
   /// UserValue - Create a new UserValue.
   UserValue(const MDNode *var, unsigned o, DebugLoc L, 
@@ -748,6 +752,13 @@ void UserValue::insertDebugValue(MachineBasicBlock *MBB, SlotIndex Idx,
     .addOperand(Loc).addImm(offset).addMetadata(variable);
 }
 
+void UserValue::insertDebugKill(MachineBasicBlock *MBB, SlotIndex Idx,
+                               LiveIntervals &LIS, const TargetInstrInfo &TII) {
+  MachineBasicBlock::iterator I = findInsertLocation(MBB, Idx, LIS);
+  BuildMI(*MBB, I, findDebugLoc(), TII.get(TargetOpcode::DBG_VALUE)).addReg(0)
+    .addImm(offset).addMetadata(variable);
+}
+
 void UserValue::emitDebugValues(VirtRegMap *VRM, LiveIntervals &LIS,
                                 const TargetInstrInfo &TII) {
   MachineFunction::iterator MFEnd = VRM->getMachineFunction().end();
@@ -779,6 +790,12 @@ void UserValue::emitDebugValues(VirtRegMap *VRM, LiveIntervals &LIS,
       break;
 
     ++I;
+    if (Stop == MBBEnd)
+      continue;
+    // The current interval ends before MBB.
+    // Insert a kill if there is a gap.
+    if (!I.valid() || I.start() > Stop)
+      insertDebugKill(MBB, Stop, LIS, TII);
   }
 }