[llvm-commits] CVS: llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp

[Nate Begeman]

Changes in directory llvm/lib/CodeGen/SelectionDAG:

LegalizeDAG.cpp updated: 1.80 -> 1.81
---
Log message:

Fix libcall code to not pass a NULL Chain to LowerCallTo
Fix libcall code to not crash or assert looking for an ADJCALLSTACKUP node
  when it is known that there is no ADJCALLSTACKDOWN to match.
Expand i64 multiply when ISD::MULHU is legal for the target.


---
Diffs of the changes:  (+30 -5)

 LegalizeDAG.cpp |   35 ++++++++++++++++++++++++++++++-----
 1 files changed, 30 insertions(+), 5 deletions(-)


Index: llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
diff -u llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp:1.80 llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp:1.81
--- llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp:1.80	Sun Apr 10 17:54:25 2005
+++ llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp	Sun Apr 10 22:01:51 2005
@@ -910,6 +910,8 @@
   case ISD::ADD:
   case ISD::SUB:
   case ISD::MUL:
+  case ISD::MULHS:
+  case ISD::MULHU:
   case ISD::UDIV:
   case ISD::SDIV:
   case ISD::AND:
@@ -1678,12 +1680,20 @@
 static SDOperand FindInputOutputChains(SDNode *OpNode, SDNode *&OutChain,
                                        SDOperand Entry) {
   SDNode *LatestAdjCallStackDown = Entry.Val;
+  SDNode *LatestAdjCallStackUp = 0;
   FindLatestAdjCallStackDown(OpNode, LatestAdjCallStackDown);
   //std::cerr << "Found node: "; LatestAdjCallStackDown->dump(); std::cerr <<"\n";
-
-  SDNode *LatestAdjCallStackUp = FindAdjCallStackUp(LatestAdjCallStackDown);
-
-
+  
+  // It is possible that no ISD::ADJCALLSTACKDOWN was found because there is no
+  // previous call in the function.  LatestCallStackDown may in that case be
+  // the entry node itself.  Do not attempt to find a matching ADJCALLSTACKUP
+  // unless LatestCallStackDown is an ADJCALLSTACKDOWN.
+  if (LatestAdjCallStackDown->getOpcode() == ISD::ADJCALLSTACKDOWN)
+    LatestAdjCallStackUp = FindAdjCallStackUp(LatestAdjCallStackDown);
+  else
+    LatestAdjCallStackUp = Entry.Val;
+  assert(LatestAdjCallStackUp && "NULL return from FindAdjCallStackUp");
+  
   SDNode *EarliestAdjCallStackUp = 0;
   FindEarliestAdjCallStackUp(OpNode, EarliestAdjCallStackUp);
 
@@ -2042,7 +2052,22 @@
     ExpandByParts(ISD::SUB_PARTS, Node->getOperand(0), Node->getOperand(1),
                   Lo, Hi);
     break;
-  case ISD::MUL:  Lo = ExpandLibCall("__muldi3" , Node, Hi); break;
+  case ISD::MUL: {
+    if (TLI.getOperationAction(ISD::MULHU, NVT) == TargetLowering::Legal) {
+      SDOperand LL, LH, RL, RH;
+      ExpandOp(Node->getOperand(0), LL, LH);
+      ExpandOp(Node->getOperand(1), RL, RH);
+      Hi = DAG.getNode(ISD::MULHU, NVT, LL, RL);
+      RH = DAG.getNode(ISD::MUL, NVT, LL, RH);
+      LH = DAG.getNode(ISD::MUL, NVT, LH, RL);
+      Hi = DAG.getNode(ISD::ADD, NVT, Hi, RH);
+      Hi = DAG.getNode(ISD::ADD, NVT, Hi, LH);
+      Lo = DAG.getNode(ISD::MUL, NVT, LL, RL);
+    } else {
+      Lo = ExpandLibCall("__muldi3" , Node, Hi); break;
+    }
+    break;
+  }
   case ISD::SDIV: Lo = ExpandLibCall("__divdi3" , Node, Hi); break;
   case ISD::UDIV: Lo = ExpandLibCall("__udivdi3", Node, Hi); break;
   case ISD::SREM: Lo = ExpandLibCall("__moddi3" , Node, Hi); break;