Update debug info when live-in reg is copied into a vreg.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104732 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
index fc830ac..3f3d4c9 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -250,6 +250,13 @@
MachineBasicBlock *EntryMBB = MF->begin();
RegInfo->EmitLiveInCopies(EntryMBB, TRI, TII);
+ DenseMap<unsigned, unsigned> LiveInMap;
+ if (!FuncInfo->ArgDbgValues.empty())
+ for (MachineRegisterInfo::livein_iterator LI = RegInfo->livein_begin(),
+ E = RegInfo->livein_end(); LI != E; ++LI)
+ if (LI->second)
+ LiveInMap.insert(std::make_pair(LI->first, LI->second));
+
// Insert DBG_VALUE instructions for function arguments to the entry block.
for (unsigned i = 0, e = FuncInfo->ArgDbgValues.size(); i != e; ++i) {
MachineInstr *MI = FuncInfo->ArgDbgValues[e-i-1];
@@ -262,6 +269,21 @@
// FIXME: VR def may not be in entry block.
Def->getParent()->insert(llvm::next(InsertPos), MI);
}
+
+ // If Reg is live-in then update debug info to track its copy in a vreg.
+ DenseMap<unsigned, unsigned>::iterator LDI = LiveInMap.find(Reg);
+ if (LDI != LiveInMap.end()) {
+ MachineInstr *Def = RegInfo->getVRegDef(LDI->second);
+ MachineBasicBlock::iterator InsertPos = Def;
+ const MDNode *Variable =
+ MI->getOperand(MI->getNumOperands()-1).getMetadata();
+ unsigned Offset = MI->getOperand(1).getImm();
+ // Def is never a terminator here, so it is ok to increment InsertPos.
+ BuildMI(*EntryMBB, ++InsertPos, MI->getDebugLoc(),
+ TII.get(TargetOpcode::DBG_VALUE))
+ .addReg(LDI->second, RegState::Debug)
+ .addImm(Offset).addMetadata(Variable);
+ }
}
// Determine if there are any calls in this machine function.