DebugInfo: Avoid propagating incorrect debug locations in SelectionDAG via CSE.

Summary:
When SelectionDAG performs CSE it is possible that the context's source
location is different from that of the selected node. This can lead to
incorrect line number records. We update the debug location to the
one that occurs earlier in the instruction sequence.

This fixes PR21006.

Reviewers: echristo, sdmitrouk

Subscribers: jevinskie, asl, llvm-commits

Differential Revision: http://reviews.llvm.org/D12094

llvm-svn: 268323

1 files changed, 37 insertions, 31 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index 5486414bee7..aa6e184cfd4 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -831,7 +831,7 @@ SDNode *SelectionDAG::FindModifiedNodeSlot(SDNode *N, SDValue Op,
   FoldingSetNodeID ID;
   AddNodeIDNode(ID, N->getOpcode(), N->getVTList(), Ops);
   AddNodeIDCustom(ID, N);
-  SDNode *Node = FindNodeOrInsertPos(ID, N->getDebugLoc(), InsertPos);
+  SDNode *Node = FindNodeOrInsertPos(ID, SDLoc(N), InsertPos);
   if (Node)
     if (const SDNodeFlags *Flags = N->getFlags())
       Node->intersectFlagsWith(Flags);
@@ -852,7 +852,7 @@ SDNode *SelectionDAG::FindModifiedNodeSlot(SDNode *N,
   FoldingSetNodeID ID;
   AddNodeIDNode(ID, N->getOpcode(), N->getVTList(), Ops);
   AddNodeIDCustom(ID, N);
-  SDNode *Node = FindNodeOrInsertPos(ID, N->getDebugLoc(), InsertPos);
+  SDNode *Node = FindNodeOrInsertPos(ID, SDLoc(N), InsertPos);
   if (Node)
     if (const SDNodeFlags *Flags = N->getFlags())
       Node->intersectFlagsWith(Flags);
@@ -872,7 +872,7 @@ SDNode *SelectionDAG::FindModifiedNodeSlot(SDNode *N, ArrayRef<SDValue> Ops,
   FoldingSetNodeID ID;
   AddNodeIDNode(ID, N->getOpcode(), N->getVTList(), Ops);
   AddNodeIDCustom(ID, N);
-  SDNode *Node = FindNodeOrInsertPos(ID, N->getDebugLoc(), InsertPos);
+  SDNode *Node = FindNodeOrInsertPos(ID, SDLoc(N), InsertPos);
   if (Node)
     if (const SDNodeFlags *Flags = N->getFlags())
       Node->intersectFlagsWith(Flags);
@@ -963,19 +963,25 @@ SDNode *SelectionDAG::FindNodeOrInsertPos(const FoldingSetNodeID &ID,
 }
 
 SDNode *SelectionDAG::FindNodeOrInsertPos(const FoldingSetNodeID &ID,
-                                          DebugLoc DL, void *&InsertPos) {
+                                          SDLoc DL, void *&InsertPos) {
   SDNode *N = CSEMap.FindNodeOrInsertPos(ID, InsertPos);
   if (N) {
     switch (N->getOpcode()) {
-    default: break; // Process only regular (non-target) constant nodes.
     case ISD::Constant:
     case ISD::ConstantFP:
       // Erase debug location from the node if the node is used at several
       // different places. Do not propagate one location to all uses as it
       // will cause a worse single stepping debugging experience.
-      if (N->getDebugLoc() != DL)
+      if (N->getDebugLoc() != DL.getDebugLoc())
         N->setDebugLoc(DebugLoc());
       break;
+    default:
+      // When the node's point of use is located earlier in the instruction
+      // sequence than its prior point of use, update its debug info to the
+      // earlier location.
+      if (DL.getIROrder() && DL.getIROrder() < N->getIROrder())
+        N->setDebugLoc(DL.getDebugLoc());
+      break;
     }
   }
   return N;
@@ -1184,7 +1190,7 @@ SDValue SelectionDAG::getConstant(const ConstantInt &Val, SDLoc DL, EVT VT,
   ID.AddBoolean(isO);
   void *IP = nullptr;
   SDNode *N = nullptr;
-  if ((N = FindNodeOrInsertPos(ID, DL.getDebugLoc(), IP)))
+  if ((N = FindNodeOrInsertPos(ID, DL, IP)))
     if (!VT.isVector())
       return SDValue(N, 0);
 
@@ -1224,7 +1230,7 @@ SDValue SelectionDAG::getConstantFP(const ConstantFP& V, SDLoc DL, EVT VT,
   ID.AddPointer(&V);
   void *IP = nullptr;
   SDNode *N = nullptr;
-  if ((N = FindNodeOrInsertPos(ID, DL.getDebugLoc(), IP)))
+  if ((N = FindNodeOrInsertPos(ID, DL, IP)))
     if (!VT.isVector())
       return SDValue(N, 0);
 
@@ -1283,7 +1289,7 @@ SDValue SelectionDAG::getGlobalAddress(const GlobalValue *GV, SDLoc DL,
   ID.AddInteger(TargetFlags);
   ID.AddInteger(GV->getType()->getAddressSpace());
   void *IP = nullptr;
-  if (SDNode *E = FindNodeOrInsertPos(ID, DL.getDebugLoc(), IP))
+  if (SDNode *E = FindNodeOrInsertPos(ID, DL, IP))
     return SDValue(E, 0);
 
   auto *N = newSDNode<GlobalAddressSDNode>(
@@ -1622,7 +1628,7 @@ SDValue SelectionDAG::getVectorShuffle(EVT VT, SDLoc dl, SDValue N1,
     ID.AddInteger(MaskVec[i]);
 
   void* IP = nullptr;
-  if (SDNode *E = FindNodeOrInsertPos(ID, dl.getDebugLoc(), IP))
+  if (SDNode *E = FindNodeOrInsertPos(ID, dl, IP))
     return SDValue(E, 0);
 
   // Allocate the mask array for the node out of the BumpPtrAllocator, since
@@ -1664,7 +1670,7 @@ SDValue SelectionDAG::getConvertRndSat(EVT VT, SDLoc dl,
   SDValue Ops[] = { Val, DTy, STy, Rnd, Sat };
   AddNodeIDNode(ID, ISD::CONVERT_RNDSAT, getVTList(VT), Ops);
   void* IP = nullptr;
-  if (SDNode *E = FindNodeOrInsertPos(ID, dl.getDebugLoc(), IP))
+  if (SDNode *E = FindNodeOrInsertPos(ID, dl, IP))
     return SDValue(E, 0);
 
   auto *N =
@@ -1794,7 +1800,7 @@ SDValue SelectionDAG::getAddrSpaceCast(SDLoc dl, EVT VT, SDValue Ptr,
   ID.AddInteger(DestAS);
 
   void *IP = nullptr;
-  if (SDNode *E = FindNodeOrInsertPos(ID, dl.getDebugLoc(), IP))
+  if (SDNode *E = FindNodeOrInsertPos(ID, dl, IP))
     return SDValue(E, 0);
 
   auto *N = newSDNode<AddrSpaceCastSDNode>(dl.getIROrder(), dl.getDebugLoc(),
@@ -2869,7 +2875,7 @@ SDValue SelectionDAG::getNode(unsigned Opcode, SDLoc DL, EVT VT) {
   FoldingSetNodeID ID;
   AddNodeIDNode(ID, Opcode, getVTList(VT), None);
   void *IP = nullptr;
-  if (SDNode *E = FindNodeOrInsertPos(ID, DL.getDebugLoc(), IP))
+  if (SDNode *E = FindNodeOrInsertPos(ID, DL, IP))
     return SDValue(E, 0);
 
   auto *N = newSDNode<SDNode>(Opcode, DL.getIROrder(), DL.getDebugLoc(),
@@ -3189,7 +3195,7 @@ SDValue SelectionDAG::getNode(unsigned Opcode, SDLoc DL,
     FoldingSetNodeID ID;
     AddNodeIDNode(ID, Opcode, VTs, Ops);
     void *IP = nullptr;
-    if (SDNode *E = FindNodeOrInsertPos(ID, DL.getDebugLoc(), IP))
+    if (SDNode *E = FindNodeOrInsertPos(ID, DL, IP))
       return SDValue(E, 0);
 
     N = newSDNode<SDNode>(Opcode, DL.getIROrder(), DL.getDebugLoc(), VTs);
@@ -3892,7 +3898,7 @@ SDValue SelectionDAG::getNode(unsigned Opcode, SDLoc DL, EVT VT, SDValue N1,
     FoldingSetNodeID ID;
     AddNodeIDNode(ID, Opcode, VTs, Ops);
     void *IP = nullptr;
-    if (SDNode *E = FindNodeOrInsertPos(ID, DL.getDebugLoc(), IP)) {
+    if (SDNode *E = FindNodeOrInsertPos(ID, DL, IP)) {
       if (Flags)
         E->intersectFlagsWith(Flags);
       return SDValue(E, 0);
@@ -3994,7 +4000,7 @@ SDValue SelectionDAG::getNode(unsigned Opcode, SDLoc DL, EVT VT,
     FoldingSetNodeID ID;
     AddNodeIDNode(ID, Opcode, VTs, Ops);
     void *IP = nullptr;
-    if (SDNode *E = FindNodeOrInsertPos(ID, DL.getDebugLoc(), IP))
+    if (SDNode *E = FindNodeOrInsertPos(ID, DL, IP))
       return SDValue(E, 0);
 
     N = newSDNode<SDNode>(Opcode, DL.getIROrder(), DL.getDebugLoc(), VTs);
@@ -4786,7 +4792,7 @@ SDValue SelectionDAG::getAtomic(unsigned Opcode, SDLoc dl, EVT MemVT,
   AddNodeIDNode(ID, Opcode, VTList, Ops);
   ID.AddInteger(MMO->getPointerInfo().getAddrSpace());
   void* IP = nullptr;
-  if (SDNode *E = FindNodeOrInsertPos(ID, dl.getDebugLoc(), IP)) {
+  if (SDNode *E = FindNodeOrInsertPos(ID, dl, IP)) {
     cast<AtomicSDNode>(E)->refineAlignment(MMO);
     return SDValue(E, 0);
   }
@@ -4982,7 +4988,7 @@ SelectionDAG::getMemIntrinsicNode(unsigned Opcode, SDLoc dl, SDVTList VTList,
     AddNodeIDNode(ID, Opcode, VTList, Ops);
     ID.AddInteger(MMO->getPointerInfo().getAddrSpace());
     void *IP = nullptr;
-    if (SDNode *E = FindNodeOrInsertPos(ID, dl.getDebugLoc(), IP)) {
+    if (SDNode *E = FindNodeOrInsertPos(ID, dl, IP)) {
       cast<MemIntrinsicSDNode>(E)->refineAlignment(MMO);
       return SDValue(E, 0);
     }
@@ -5108,7 +5114,7 @@ SelectionDAG::getLoad(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType,
                                      MMO->isInvariant()));
   ID.AddInteger(MMO->getPointerInfo().getAddrSpace());
   void *IP = nullptr;
-  if (SDNode *E = FindNodeOrInsertPos(ID, dl.getDebugLoc(), IP)) {
+  if (SDNode *E = FindNodeOrInsertPos(ID, dl, IP)) {
     cast<LoadSDNode>(E)->refineAlignment(MMO);
     return SDValue(E, 0);
   }
@@ -5215,7 +5221,7 @@ SDValue SelectionDAG::getStore(SDValue Chain, SDLoc dl, SDValue Val,
                                      MMO->isNonTemporal(), MMO->isInvariant()));
   ID.AddInteger(MMO->getPointerInfo().getAddrSpace());
   void *IP = nullptr;
-  if (SDNode *E = FindNodeOrInsertPos(ID, dl.getDebugLoc(), IP)) {
+  if (SDNode *E = FindNodeOrInsertPos(ID, dl, IP)) {
     cast<StoreSDNode>(E)->refineAlignment(MMO);
     return SDValue(E, 0);
   }
@@ -5285,7 +5291,7 @@ SDValue SelectionDAG::getTruncStore(SDValue Chain, SDLoc dl, SDValue Val,
                                      MMO->isNonTemporal(), MMO->isInvariant()));
   ID.AddInteger(MMO->getPointerInfo().getAddrSpace());
   void *IP = nullptr;
-  if (SDNode *E = FindNodeOrInsertPos(ID, dl.getDebugLoc(), IP)) {
+  if (SDNode *E = FindNodeOrInsertPos(ID, dl, IP)) {
     cast<StoreSDNode>(E)->refineAlignment(MMO);
     return SDValue(E, 0);
   }
@@ -5311,7 +5317,7 @@ SelectionDAG::getIndexedStore(SDValue OrigStore, SDLoc dl, SDValue Base,
   ID.AddInteger(ST->getRawSubclassData());
   ID.AddInteger(ST->getPointerInfo().getAddrSpace());
   void *IP = nullptr;
-  if (SDNode *E = FindNodeOrInsertPos(ID, dl.getDebugLoc(), IP))
+  if (SDNode *E = FindNodeOrInsertPos(ID, dl, IP))
     return SDValue(E, 0);
 
   auto *N = newSDNode<StoreSDNode>(dl.getIROrder(), dl.getDebugLoc(), VTs, AM,
@@ -5340,7 +5346,7 @@ SelectionDAG::getMaskedLoad(EVT VT, SDLoc dl, SDValue Chain,
                                      MMO->isInvariant()));
   ID.AddInteger(MMO->getPointerInfo().getAddrSpace());
   void *IP = nullptr;
-  if (SDNode *E = FindNodeOrInsertPos(ID, dl.getDebugLoc(), IP)) {
+  if (SDNode *E = FindNodeOrInsertPos(ID, dl, IP)) {
     cast<MaskedLoadSDNode>(E)->refineAlignment(MMO);
     return SDValue(E, 0);
   }
@@ -5368,7 +5374,7 @@ SDValue SelectionDAG::getMaskedStore(SDValue Chain, SDLoc dl, SDValue Val,
                                      MMO->isNonTemporal(), MMO->isInvariant()));
   ID.AddInteger(MMO->getPointerInfo().getAddrSpace());
   void *IP = nullptr;
-  if (SDNode *E = FindNodeOrInsertPos(ID, dl.getDebugLoc(), IP)) {
+  if (SDNode *E = FindNodeOrInsertPos(ID, dl, IP)) {
     cast<MaskedStoreSDNode>(E)->refineAlignment(MMO);
     return SDValue(E, 0);
   }
@@ -5396,7 +5402,7 @@ SelectionDAG::getMaskedGather(SDVTList VTs, EVT VT, SDLoc dl,
                                      MMO->isInvariant()));
   ID.AddInteger(MMO->getPointerInfo().getAddrSpace());
   void *IP = nullptr;
-  if (SDNode *E = FindNodeOrInsertPos(ID, dl.getDebugLoc(), IP)) {
+  if (SDNode *E = FindNodeOrInsertPos(ID, dl, IP)) {
     cast<MaskedGatherSDNode>(E)->refineAlignment(MMO);
     return SDValue(E, 0);
   }
@@ -5432,7 +5438,7 @@ SDValue SelectionDAG::getMaskedScatter(SDVTList VTs, EVT VT, SDLoc dl,
                                      MMO->isInvariant()));
   ID.AddInteger(MMO->getPointerInfo().getAddrSpace());
   void *IP = nullptr;
-  if (SDNode *E = FindNodeOrInsertPos(ID, dl.getDebugLoc(), IP)) {
+  if (SDNode *E = FindNodeOrInsertPos(ID, dl, IP)) {
     cast<MaskedScatterSDNode>(E)->refineAlignment(MMO);
     return SDValue(E, 0);
   }
@@ -5522,7 +5528,7 @@ SDValue SelectionDAG::getNode(unsigned Opcode, SDLoc DL, EVT VT,
     AddNodeIDNode(ID, Opcode, VTs, Ops);
     void *IP = nullptr;
 
-    if (SDNode *E = FindNodeOrInsertPos(ID, DL.getDebugLoc(), IP))
+    if (SDNode *E = FindNodeOrInsertPos(ID, DL, IP))
       return SDValue(E, 0);
 
     N = newSDNode<SDNode>(Opcode, DL.getIROrder(), DL.getDebugLoc(), VTs);
@@ -5577,7 +5583,7 @@ SDValue SelectionDAG::getNode(unsigned Opcode, SDLoc DL, SDVTList VTList,
     FoldingSetNodeID ID;
     AddNodeIDNode(ID, Opcode, VTList, Ops);
     void *IP = nullptr;
-    if (SDNode *E = FindNodeOrInsertPos(ID, DL.getDebugLoc(), IP))
+    if (SDNode *E = FindNodeOrInsertPos(ID, DL, IP))
       return SDValue(E, 0);
 
     N = newSDNode<SDNode>(Opcode, DL.getIROrder(), DL.getDebugLoc(), VTList);
@@ -5976,7 +5982,7 @@ SDNode *SelectionDAG::MorphNodeTo(SDNode *N, unsigned Opc,
   if (VTs.VTs[VTs.NumVTs-1] != MVT::Glue) {
     FoldingSetNodeID ID;
     AddNodeIDNode(ID, Opc, VTs, Ops);
-    if (SDNode *ON = FindNodeOrInsertPos(ID, N->getDebugLoc(), IP))
+    if (SDNode *ON = FindNodeOrInsertPos(ID, SDLoc(N), IP))
       return UpdadeSDLocOnMergedSDNode(ON, SDLoc(N));
   }
 
@@ -6157,7 +6163,7 @@ SelectionDAG::getMachineNode(unsigned Opcode, SDLoc DL, SDVTList VTs,
     FoldingSetNodeID ID;
     AddNodeIDNode(ID, ~Opcode, VTs, Ops);
     IP = nullptr;
-    if (SDNode *E = FindNodeOrInsertPos(ID, DL.getDebugLoc(), IP)) {
+    if (SDNode *E = FindNodeOrInsertPos(ID, DL, IP)) {
       return cast<MachineSDNode>(UpdadeSDLocOnMergedSDNode(E, DL));
     }
   }
@@ -6204,7 +6210,7 @@ SDNode *SelectionDAG::getNodeIfExists(unsigned Opcode, SDVTList VTList,
     FoldingSetNodeID ID;
     AddNodeIDNode(ID, Opcode, VTList, Ops);
     void *IP = nullptr;
-    if (SDNode *E = FindNodeOrInsertPos(ID, DebugLoc(), IP)) {
+    if (SDNode *E = FindNodeOrInsertPos(ID, SDLoc(), IP)) {
       if (Flags)
         E->intersectFlagsWith(Flags);
       return E;