When the legalizer is splitting vector shifts, the result may not have the right shift amount type.

Fix that by adding a cast to the shift expander. This came up with vector shifts
on sse-less X86 CPUs.

   <2 x i64>       = shl <2 x i64> <2 x i64>
-> i64,i64         = shl i64 i64; shl i64 i64
-> i32,i32,i32,i32 = shl_parts i32 i32 i64; shl_parts i32 i32 i64

Now we cast the last two i64s to the right type. Fixes the crash in PR14668.

llvm-svn: 173615

1 files changed, 9 insertions, 2 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp b/llvm/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp
index 5da6d29aab9..e08dd6dcb6d 100644
--- a/llvm/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp
@@ -2095,9 +2095,16 @@ void DAGTypeLegalizer::ExpandIntRes_Shift(SDNode *N,
     // Expand the subcomponents.
     SDValue LHSL, LHSH;
     GetExpandedInteger(N->getOperand(0), LHSL, LHSH);
-
-    SDValue Ops[] = { LHSL, LHSH, N->getOperand(1) };
     EVT VT = LHSL.getValueType();
+
+    // If the shift amount operand is coming from a vector legalization it may
+    // not have the right return type.  Fix that first by casting the operand.
+    SDValue ShiftOp = N->getOperand(1);
+    MVT ShiftTy = TLI.getShiftAmountTy(VT);
+    if (ShiftOp.getValueType() != ShiftTy)
+      ShiftOp = DAG.getZExtOrTrunc(ShiftOp, dl, ShiftTy);
+
+    SDValue Ops[] = { LHSL, LHSH, ShiftOp };
     Lo = DAG.getNode(PartsOpc, dl, DAG.getVTList(VT, VT), Ops, 3);
     Hi = Lo.getValue(1);
     return;