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 8b110e3..9935626 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 102c71b..7e6aaf3 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 9e1782e..5e88e95 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 54ca2c9..491ccc4 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 1566c09..cd3cb0d 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 968e536..9847692 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 d4378c2..b0dfca3 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 aed0fbb..3140e53 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 ba75a44..1d28b77 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 a709685..0afdd1a 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 d436ba9..442f0c4 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 968b358..6fe6bd8 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.
   }