From: Chris Lattner Date: Sat, 6 May 2006 22:43:44 +0000 (+0000) Subject: remove cases handled elsewhere X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=541a24f7af685610838b5a89b2feffc2285937db;p=oota-llvm.git remove cases handled elsewhere git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28150 91177308-0d34-0410-b5e6-96231b3b80d8 --- diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index 16ce87a5361..3f9b77467d2 100644 --- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -1938,30 +1938,16 @@ SDOperand DAGCombiner::visitSIGN_EXTEND_INREG(SDNode *N) { return DAG.getNode(ISD::SIGN_EXTEND, VT, Truncate); } - // If the input is already sign extended, just drop the extend. + // If the input is already sign extended, just drop the extension. if (TLI.ComputeNumSignBits(N0) >= MVT::getSizeInBits(VT)-EVTBits+1) return N0; - // fold (sext_in_reg (sext_in_reg x, VT2), VT1) -> (sext_in_reg x, minVT) pt1 - if (N0.getOpcode() == ISD::SIGN_EXTEND_INREG && - cast(N0.getOperand(1))->getVT() <= EVT) { - return N0; - } // fold (sext_in_reg (sext_in_reg x, VT2), VT1) -> (sext_in_reg x, minVT) pt2 if (N0.getOpcode() == ISD::SIGN_EXTEND_INREG && EVT < cast(N0.getOperand(1))->getVT()) { return DAG.getNode(ISD::SIGN_EXTEND_INREG, VT, N0.getOperand(0), N1); } - // fold (sext_in_reg (sextload x)) -> (sextload x) - if (N0.getOpcode() == ISD::SEXTLOAD && - cast(N0.getOperand(3))->getVT() <= EVT) { - return N0; - } - // fold (sext_in_reg (setcc x)) -> setcc x iff (setcc x) == 0 or -1 - if (N0.getOpcode() == ISD::SETCC && - TLI.getSetCCResultContents() == - TargetLowering::ZeroOrNegativeOneSetCCResult) - return N0; + // fold (sext_in_reg x) -> (zext_in_reg x) if the sign bit is zero if (TLI.MaskedValueIsZero(N0, 1ULL << (EVTBits-1))) return DAG.getZeroExtendInReg(N0, EVT);