Add VerifyNode, a place to put sanity checks on

generic SDNode's (nodes with their own constructors
should do sanity checking in the constructor).  Add
sanity checks for BUILD_VECTOR and fix all the places
that were producing bogus BUILD_VECTORs, as found by
"make check".  My favorite is the BUILD_VECTOR with
only two operands that was being used to build a
vector with four elements!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53850 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 44 insertions, 6 deletions

diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 14efb446fe..aff3869918 100644
--- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -5011,7 +5011,8 @@ SDOperand DAGCombiner::visitVECTOR_SHUFFLE(SDNode *N) {
       } else {
         unsigned NewIdx = 
           cast<ConstantSDNode>(ShufMask.getOperand(i))->getValue() - NumElts;
-        MappedOps.push_back(DAG.getConstant(NewIdx, MVT::i32));
+        MappedOps.push_back(DAG.getConstant(NewIdx,
+                                        ShufMask.getOperand(i).getValueType()));
       }
     }
     ShufMask = DAG.getNode(ISD::BUILD_VECTOR, ShufMask.getValueType(),
diff --git a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
index 4b02c54a4e..b49fa9be53 100644
--- a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
@@ -186,7 +186,7 @@ private:
   /// scalar (e.g. f32) value.
   SDOperand ScalarizeVectorOp(SDOperand O);
   
-  /// isShuffleLegal - Return true if a vector shuffle is legal with the
+  /// isShuffleLegal - Return non-null if a vector shuffle is legal with the
   /// specified mask and type.  Targets can specify exactly which masks they
   /// support and the code generator is tasked with not creating illegal masks.
   ///
@@ -241,6 +241,7 @@ SDNode *SelectionDAGLegalize::isShuffleLegal(MVT VT, SDOperand Mask) const {
     // If this is promoted to a different type, convert the shuffle mask and
     // ask if it is legal in the promoted type!
     MVT NVT = TLI.getTypeToPromoteTo(ISD::VECTOR_SHUFFLE, VT);
+    MVT EltVT = NVT.getVectorElementType();
 
     // If we changed # elements, change the shuffle mask.
     unsigned NumEltsGrowth =
@@ -253,10 +254,10 @@ SDNode *SelectionDAGLegalize::isShuffleLegal(MVT VT, SDOperand Mask) const {
         SDOperand InOp = Mask.getOperand(i);
         for (unsigned j = 0; j != NumEltsGrowth; ++j) {
           if (InOp.getOpcode() == ISD::UNDEF)
-            Ops.push_back(DAG.getNode(ISD::UNDEF, MVT::i32));
+            Ops.push_back(DAG.getNode(ISD::UNDEF, EltVT));
           else {
             unsigned InEltNo = cast<ConstantSDNode>(InOp)->getValue();
-            Ops.push_back(DAG.getConstant(InEltNo*NumEltsGrowth+j, MVT::i32));
+            Ops.push_back(DAG.getConstant(InEltNo*NumEltsGrowth+j, EltVT));
           }
         }
       }
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index e757133f99..882985f662 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -740,6 +740,25 @@ SDNode *SelectionDAG::FindModifiedNodeSlot(SDNode *N,
   return CSEMap.FindNodeOrInsertPos(ID, InsertPos);
 }
 
+/// VerifyNode - Sanity check the given node.  Aborts if it is invalid.
+void SelectionDAG::VerifyNode(SDNode *N) {
+  switch (N->getOpcode()) {
+  default:
+    break;
+  case ISD::BUILD_VECTOR: {
+    assert(N->getNumValues() == 1 && "Too many results for BUILD_VECTOR!");
+    assert(N->getValueType(0).isVector() && "Wrong BUILD_VECTOR return type!");
+    assert(N->getNumOperands() == N->getValueType(0).getVectorNumElements() &&
+           "Wrong number of BUILD_VECTOR operands!");
+    MVT EltVT = N->getValueType(0).getVectorElementType();
+    for (SDNode::op_iterator I = N->op_begin(), E = N->op_end(); I != E; ++I)
+      assert(I->getSDOperand().getValueType() == EltVT &&
+             "Wrong BUILD_VECTOR operand type!");
+    break;
+  }
+  }
+}
+
 /// getMVTAlignment - Compute the default alignment value for the
 /// given type.
 ///
@@ -1965,6 +1984,9 @@ SDOperand SelectionDAG::getNode(unsigned Opcode, MVT VT) {
   CSEMap.InsertNode(N, IP);
   
   AllNodes.push_back(N);
+#ifndef NDEBUG
+  VerifyNode(N);
+#endif
   return SDOperand(N, 0);
 }
 
@@ -2161,12 +2183,14 @@ SDOperand SelectionDAG::getNode(unsigned Opcode, MVT VT, SDOperand Operand) {
     N = getAllocator().Allocate<UnarySDNode>();
     new (N) UnarySDNode(Opcode, VTs, Operand);
   }
+
   AllNodes.push_back(N);
+#ifndef NDEBUG
+  VerifyNode(N);
+#endif
   return SDOperand(N, 0);
 }
 
-
-
 SDOperand SelectionDAG::getNode(unsigned Opcode, MVT VT,
                                 SDOperand N1, SDOperand N2) {
   ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1.Val);
@@ -2515,6 +2539,9 @@ SDOperand SelectionDAG::getNode(unsigned Opcode, MVT VT,
   }
 
   AllNodes.push_back(N);
+#ifndef NDEBUG
+  VerifyNode(N);
+#endif
   return SDOperand(N, 0);
 }
 
@@ -2580,6 +2607,9 @@ SDOperand SelectionDAG::getNode(unsigned Opcode, MVT VT,
     new (N) TernarySDNode(Opcode, VTs, N1, N2, N3);
   }
   AllNodes.push_back(N);
+#ifndef NDEBUG
+  VerifyNode(N);
+#endif
   return SDOperand(N, 0);
 }
 
@@ -3394,6 +3424,9 @@ SDOperand SelectionDAG::getNode(unsigned Opcode, MVT VT,
     new (N) SDNode(Opcode, VTs, Ops, NumOps);
   }
   AllNodes.push_back(N);
+#ifndef NDEBUG
+  VerifyNode(N);
+#endif
   return SDOperand(N, 0);
 }
 
@@ -3478,6 +3511,9 @@ SDOperand SelectionDAG::getNode(unsigned Opcode, SDVTList VTList,
     }
   }
   AllNodes.push_back(N);
+#ifndef NDEBUG
+  VerifyNode(N);
+#endif
   return SDOperand(N, 0);
 }