Fix an assertion failure when optimising a shufflevector incorrectly into concat_vectors, and a followup bug with SelectionDAG::getNode() creating nodes with invalid types.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163511 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 22 insertions, 10 deletions

diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 4caafa5..d7fa009 100644
--- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -8095,6 +8095,12 @@ SDValue DAGCombiner::visitBUILD_VECTOR(SDNode *N) {
       if (VecIn1.getValueType().getSizeInBits()*2 != VT.getSizeInBits())
         return SDValue();
 
+      // If the input vector type has a different base type to the output
+      // vector type, bail out.
+      if (VecIn1.getValueType().getVectorElementType() !=
+          VT.getVectorElementType())
+        return SDValue();
+
       // Widen the input vector by adding undef values.
       VecIn1 = DAG.getNode(ISD::CONCAT_VECTORS, N->getDebugLoc(), VT,
                            VecIn1, DAG.getUNDEF(VecIn1.getValueType()));
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index 928385a..a2265c2 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -2934,17 +2934,13 @@ SDValue SelectionDAG::getNode(unsigned Opcode, DebugLoc DL, EVT VT,
     // expanding large vector constants.
     if (N2C && N1.getOpcode() == ISD::BUILD_VECTOR) {
       SDValue Elt = N1.getOperand(N2C->getZExtValue());
-      EVT VEltTy = N1.getValueType().getVectorElementType();
-      if (Elt.getValueType() != VEltTy) {
+
+      if (VT != Elt.getValueType())
         // If the vector element type is not legal, the BUILD_VECTOR operands
-        // are promoted and implicitly truncated.  Make that explicit here.
-        Elt = getNode(ISD::TRUNCATE, DL, VEltTy, Elt);
-      }
-      if (VT != VEltTy) {
-        // If the vector element type is not legal, the EXTRACT_VECTOR_ELT
-        // result is implicitly extended.
-        Elt = getNode(ISD::ANY_EXTEND, DL, VT, Elt);
-      }
+        // are promoted and implicitly truncated, and the result implicitly
+        // extended. Make that explicit here.
+        Elt = getAnyExtOrTrunc(Elt, DL, VT);
+      
       return Elt;
     }
 
diff --git a/test/CodeGen/ARM/crash-shufflevector.ll b/test/CodeGen/ARM/crash-shufflevector.ll
new file mode 100644
index 0000000..bdc0e0e
--- /dev/null
+++ b/test/CodeGen/ARM/crash-shufflevector.ll
@@ -0,0 +1,10 @@
+; RUN: llc < %s -mtriple=armv7
+
+declare void @g(<16 x i8>)
+define void @f(<4 x i8> %param1, <4 x i8> %param2) {
+   %y1 = shufflevector <4 x i8> %param1, <4 x i8> undef, <16 x i32> <i32 0, i32 1, i32 2, i32 3, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef>
+   %y2 = shufflevector <4 x i8> %param2, <4 x i8> undef, <16 x i32> <i32 0, i32 1, i32 2, i32 3, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef, i32 undef>
+   %z = shufflevector <16 x i8> %y1, <16 x i8> %y2, <16 x i32> <i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7, i32 8, i32 9, i32 10, i32 11, i32 16, i32 17, i32 18, i32 19>
+   call void @g(<16 x i8> %z)
+   ret void
+}
\ No newline at end of file