Fix PromoteIntRes_BUILD_VECTOR crash with i1 vectors

This fixes a bug (found by llvm-stress) in
DAGTypeLegalizer::PromoteIntRes_BUILD_VECTOR where it assumed that the result
type would always be larger than the original operands. This is not always
true, however, with boolean vectors. For example, promoting a node of type v8i1
(where the operands will be of type i32, the type to which i1 is promoted) will
yield a node with a result vector element type of i16 (and operands of type
i32). As a result, we cannot blindly assume that we can ANY_EXTEND the operands
to the result type.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185794 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 7 insertions, 1 deletions

diff --git a/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp b/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp
index b3ec9bc..df38898 100644
--- a/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp
+++ b/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp
@@ -2930,7 +2930,13 @@ SDValue DAGTypeLegalizer::PromoteIntRes_BUILD_VECTOR(SDNode *N) {
   SmallVector<SDValue, 8> Ops;
   Ops.reserve(NumElems);
   for (unsigned i = 0; i != NumElems; ++i) {
-    SDValue Op = DAG.getNode(ISD::ANY_EXTEND, dl, NOutVTElem, N->getOperand(i));
+    SDValue Op;
+    // It is possible for the operands to be larger than the result, for example,
+    // when the operands are promoted booleans and the result was an i1 vector.
+    if (N->getOperand(i).getValueType().bitsLT(NOutVTElem))
+      Op = DAG.getNode(ISD::ANY_EXTEND, dl, NOutVTElem, N->getOperand(i));
+    else
+      Op = N->getOperand(i);
     Ops.push_back(Op);
   }