Pull in r191165 from upstream llvm trunk:

  ISelDAG: spot chain cycles involving MachineNodes

  Previously, the DAGISel function WalkChainUsers was spotting that it
  had entered already-selected territory by whether a node was a
  MachineNode (amongst other things). Since it's fairly common practice
  to insert MachineNodes during ISelLowering, this was not the correct
  check.

  Looking around, it seems that other nodes get their NodeId set to -1
  upon selection, so this makes sure the same thing happens to all
  MachineNodes and uses that characteristic to determine whether we
  should stop looking for a loop during selection.

  This should fix PR15840.

Specifically, this fixes the long-standing assertion failure when
compiling the multimedia/gstreamer port on i386.  Thanks to Tijl
Coosemans for his help in getting upstream to fix it.

Approved by:	re (marius)

12 files changed, 26 insertions, 10 deletions

diff --git a/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
index 8b110e300317..99356264e903 100644
--- a/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ b/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -1736,15 +1736,15 @@ WalkChainUsers(const SDNode *ChainedNode,
 
     SDNode *User = *UI;
 
+    if (User->getOpcode() == ISD::HANDLENODE)  // Root of the graph.
+      continue;
+
     // If we see an already-selected machine node, then we've gone beyond the
     // pattern that we're selecting down into the already selected chunk of the
     // DAG.
-    if (User->isMachineOpcode() ||
-        User->getOpcode() == ISD::HANDLENODE)  // Root of the graph.
-      continue;
-
     unsigned UserOpcode = User->getOpcode();
-    if (UserOpcode == ISD::CopyToReg ||
+    if (User->isMachineOpcode() ||
+        UserOpcode == ISD::CopyToReg ||
         UserOpcode == ISD::CopyFromReg ||
         UserOpcode == ISD::INLINEASM ||
         UserOpcode == ISD::EH_LABEL ||
diff --git a/contrib/llvm/lib/Target/AArch64/AArch64ISelDAGToDAG.cpp b/contrib/llvm/lib/Target/AArch64/AArch64ISelDAGToDAG.cpp
index 102c71b5d989..7e6aaf38108f 100644
--- a/contrib/llvm/lib/Target/AArch64/AArch64ISelDAGToDAG.cpp
+++ b/contrib/llvm/lib/Target/AArch64/AArch64ISelDAGToDAG.cpp
@@ -395,6 +395,7 @@ SDNode *AArch64DAGToDAGISel::Select(SDNode *Node) {
 
   if (Node->isMachineOpcode()) {
     DEBUG(dbgs() << "== "; Node->dump(CurDAG); dbgs() << "\n");
+    Node->setNodeId(-1);
     return NULL;
   }
 
diff --git a/contrib/llvm/lib/Target/ARM/ARMISelDAGToDAG.cpp b/contrib/llvm/lib/Target/ARM/ARMISelDAGToDAG.cpp
index 9e1782e1191c..5e88e95d6162 100644
--- a/contrib/llvm/lib/Target/ARM/ARMISelDAGToDAG.cpp
+++ b/contrib/llvm/lib/Target/ARM/ARMISelDAGToDAG.cpp
@@ -2546,8 +2546,10 @@ SDNode *ARMDAGToDAGISel::SelectAtomic64(SDNode *Node, unsigned Opc) {
 SDNode *ARMDAGToDAGISel::Select(SDNode *N) {
   DebugLoc dl = N->getDebugLoc();
 
-  if (N->isMachineOpcode())
+  if (N->isMachineOpcode()) {
+    N->setNodeId(-1);
     return NULL;   // Already selected.
+  }
 
   switch (N->getOpcode()) {
   default: break;
diff --git a/contrib/llvm/lib/Target/Hexagon/HexagonISelDAGToDAG.cpp b/contrib/llvm/lib/Target/Hexagon/HexagonISelDAGToDAG.cpp
index 54ca2c97ea02..491ccc4142b3 100644
--- a/contrib/llvm/lib/Target/Hexagon/HexagonISelDAGToDAG.cpp
+++ b/contrib/llvm/lib/Target/Hexagon/HexagonISelDAGToDAG.cpp
@@ -1334,8 +1334,10 @@ SDNode *HexagonDAGToDAGISel::SelectAdd(SDNode *N) {
 
 
 SDNode *HexagonDAGToDAGISel::Select(SDNode *N) {
-  if (N->isMachineOpcode())
+  if (N->isMachineOpcode()) {
+    N->setNodeId(-1);
     return NULL;   // Already selected.
+  }
 
 
   switch (N->getOpcode()) {
diff --git a/contrib/llvm/lib/Target/MSP430/MSP430ISelDAGToDAG.cpp b/contrib/llvm/lib/Target/MSP430/MSP430ISelDAGToDAG.cpp
index 1566c096037e..cd3cb0dd6c3e 100644
--- a/contrib/llvm/lib/Target/MSP430/MSP430ISelDAGToDAG.cpp
+++ b/contrib/llvm/lib/Target/MSP430/MSP430ISelDAGToDAG.cpp
@@ -394,6 +394,7 @@ SDNode *MSP430DAGToDAGISel::Select(SDNode *Node) {
     DEBUG(errs() << "== ";
           Node->dump(CurDAG);
           errs() << "\n");
+    Node->setNodeId(-1);
     return NULL;
   }
 
diff --git a/contrib/llvm/lib/Target/Mips/MipsISelDAGToDAG.cpp b/contrib/llvm/lib/Target/Mips/MipsISelDAGToDAG.cpp
index 968e5364842f..98476929d21f 100644
--- a/contrib/llvm/lib/Target/Mips/MipsISelDAGToDAG.cpp
+++ b/contrib/llvm/lib/Target/Mips/MipsISelDAGToDAG.cpp
@@ -97,6 +97,7 @@ SDNode* MipsDAGToDAGISel::Select(SDNode *Node) {
   // If we have a custom node, we already have selected!
   if (Node->isMachineOpcode()) {
     DEBUG(errs() << "== "; Node->dump(CurDAG); errs() << "\n");
+    Node->setNodeId(-1);
     return NULL;
   }
 
diff --git a/contrib/llvm/lib/Target/NVPTX/NVPTXISelDAGToDAG.cpp b/contrib/llvm/lib/Target/NVPTX/NVPTXISelDAGToDAG.cpp
index d4378c2322d4..b0dfca37630a 100644
--- a/contrib/llvm/lib/Target/NVPTX/NVPTXISelDAGToDAG.cpp
+++ b/contrib/llvm/lib/Target/NVPTX/NVPTXISelDAGToDAG.cpp
@@ -91,8 +91,10 @@ NVPTXDAGToDAGISel::NVPTXDAGToDAGISel(NVPTXTargetMachine &tm,
 /// expanded, promoted and normal instructions.
 SDNode *NVPTXDAGToDAGISel::Select(SDNode *N) {
 
-  if (N->isMachineOpcode())
+  if (N->isMachineOpcode()) {
+    N->setNodeId(-1);
     return NULL; // Already selected.
+  }
 
   SDNode *ResNode = NULL;
   switch (N->getOpcode()) {
diff --git a/contrib/llvm/lib/Target/PowerPC/PPCISelDAGToDAG.cpp b/contrib/llvm/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
index aed0fbb6c84e..3140e53bf94e 100644
--- a/contrib/llvm/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
+++ b/contrib/llvm/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
@@ -895,8 +895,10 @@ SDNode *PPCDAGToDAGISel::SelectSETCC(SDNode *N) {
 // target-specific node if it hasn't already been changed.
 SDNode *PPCDAGToDAGISel::Select(SDNode *N) {
   DebugLoc dl = N->getDebugLoc();
-  if (N->isMachineOpcode())
+  if (N->isMachineOpcode()) {
+    N->setNodeId(-1);
     return NULL;   // Already selected.
+  }
 
   switch (N->getOpcode()) {
   default: break;
diff --git a/contrib/llvm/lib/Target/R600/AMDILISelDAGToDAG.cpp b/contrib/llvm/lib/Target/R600/AMDILISelDAGToDAG.cpp
index ba75a44ea1f1..1d28b773a62a 100644
--- a/contrib/llvm/lib/Target/R600/AMDILISelDAGToDAG.cpp
+++ b/contrib/llvm/lib/Target/R600/AMDILISelDAGToDAG.cpp
@@ -158,6 +158,7 @@ bool AMDGPUDAGToDAGISel::SelectADDR64(SDValue Addr, SDValue& R1, SDValue& R2) {
 SDNode *AMDGPUDAGToDAGISel::Select(SDNode *N) {
   unsigned int Opc = N->getOpcode();
   if (N->isMachineOpcode()) {
+    N->setNodeId(-1);
     return NULL;   // Already selected.
   }
   switch (Opc) {
diff --git a/contrib/llvm/lib/Target/Sparc/SparcISelDAGToDAG.cpp b/contrib/llvm/lib/Target/Sparc/SparcISelDAGToDAG.cpp
index a709685cd08c..0afdd1a67a80 100644
--- a/contrib/llvm/lib/Target/Sparc/SparcISelDAGToDAG.cpp
+++ b/contrib/llvm/lib/Target/Sparc/SparcISelDAGToDAG.cpp
@@ -137,8 +137,10 @@ bool SparcDAGToDAGISel::SelectADDRrr(SDValue Addr, SDValue &R1, SDValue &R2) {
 
 SDNode *SparcDAGToDAGISel::Select(SDNode *N) {
   DebugLoc dl = N->getDebugLoc();
-  if (N->isMachineOpcode())
+  if (N->isMachineOpcode()) {
+    N->setNodeId(-1);
     return NULL;   // Already selected.
+  }
 
   switch (N->getOpcode()) {
   default: break;
diff --git a/contrib/llvm/lib/Target/SystemZ/SystemZISelDAGToDAG.cpp b/contrib/llvm/lib/Target/SystemZ/SystemZISelDAGToDAG.cpp
index d436ba9dd078..442f0c4d1ef2 100644
--- a/contrib/llvm/lib/Target/SystemZ/SystemZISelDAGToDAG.cpp
+++ b/contrib/llvm/lib/Target/SystemZ/SystemZISelDAGToDAG.cpp
@@ -540,6 +540,7 @@ SDNode *SystemZDAGToDAGISel::Select(SDNode *Node) {
   // If we have a custom node, we already have selected!
   if (Node->isMachineOpcode()) {
     DEBUG(errs() << "== "; Node->dump(CurDAG); errs() << "\n");
+    Node->setNodeId(-1);
     return 0;
   }
 
diff --git a/contrib/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp b/contrib/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp
index 968b3583c36d..6fe6bd85bb0e 100644
--- a/contrib/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp
+++ b/contrib/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp
@@ -1988,6 +1988,7 @@ SDNode *X86DAGToDAGISel::Select(SDNode *Node) {
 
   if (Node->isMachineOpcode()) {
     DEBUG(dbgs() << "== ";  Node->dump(CurDAG); dbgs() << '\n');
+    Node->setNodeId(-1);
     return NULL;   // Already selected.
   }