From 022688c260f472b4befcd974a6c907c6830f308e Mon Sep 17 00:00:00 2001 From: Benjamin Kramer Date: Sun, 27 Jan 2013 15:04:43 +0000 Subject: [PATCH] Legalizer: Add an assert and tweak a comment to clarify the assumptions this code makes. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173620 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp b/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp index e08dd6dcb6d..88e72ecd929 100644 --- a/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp +++ b/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp @@ -2098,9 +2098,13 @@ void DAGTypeLegalizer::ExpandIntRes_Shift(SDNode *N, 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. + // have an illegal type. Fix that first by casting the operand. Otherwise + // the new SHL_PARTS operation would need further legalization, and the + // legalizer assumes that illegal SHL_PARTS never occur. SDValue ShiftOp = N->getOperand(1); MVT ShiftTy = TLI.getShiftAmountTy(VT); + assert(ShiftTy.getSizeInBits() >= Log2_32_Ceil(VT.getSizeInBits()) && + "ShiftAmountTy is too small to cover the range of this type!"); if (ShiftOp.getValueType() != ShiftTy) ShiftOp = DAG.getZExtOrTrunc(ShiftOp, dl, ShiftTy);