From d4b841f8f9992f06eb8bd39145bc305a5e84e159 Mon Sep 17 00:00:00 2001 From: Owen Anderson Date: Mon, 9 Jul 2012 20:31:12 +0000 Subject: Teach the DAG combiner to turn sitofp/uitofp from i1 into a conditional move, since there are only two possible values. Previously, this would become an integer extension operation, followed by a real integer->float conversion. llvm-svn: 159957 --- llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 36 +++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) (limited to 'llvm/lib/CodeGen/SelectionDAG') diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index 28c3be9eb60..02877862b49 100644 --- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -5974,6 +5974,30 @@ SDValue DAGCombiner::visitSINT_TO_FP(SDNode *N) { return DAG.getNode(ISD::UINT_TO_FP, N->getDebugLoc(), VT, N0); } + // fold (sint_to_fp (setcc x, y, cc)) -> (select_cc x, y, -1.0, 0.0,, cc) + if (N0.getOpcode() == ISD::SETCC && !VT.isVector() && + (!LegalOperations || + TLI.isOperationLegalOrCustom(llvm::ISD::ConstantFP, VT))) { + SDValue Ops[] = + { N0.getOperand(0), N0.getOperand(1), + DAG.getConstantFP(-1.0, VT) , DAG.getConstantFP(0.0, VT), + N0.getOperand(2) }; + return DAG.getNode(ISD::SELECT_CC, N->getDebugLoc(), VT, Ops, 5); + } + + // fold (sint_to_fp (zext (setcc x, y, cc))) -> + // (select_cc x, y, 1.0, 0.0,, cc) + if (N0.getOpcode() == ISD::ZERO_EXTEND && + N0.getOperand(0).getOpcode() == ISD::SETCC &&!VT.isVector() && + (!LegalOperations || + TLI.isOperationLegalOrCustom(llvm::ISD::ConstantFP, VT))) { + SDValue Ops[] = + { N0.getOperand(0).getOperand(0), N0.getOperand(0).getOperand(1), + DAG.getConstantFP(1.0, VT) , DAG.getConstantFP(0.0, VT), + N0.getOperand(0).getOperand(2) }; + return DAG.getNode(ISD::SELECT_CC, N->getDebugLoc(), VT, Ops, 5); + } + return SDValue(); } @@ -5999,6 +6023,18 @@ SDValue DAGCombiner::visitUINT_TO_FP(SDNode *N) { return DAG.getNode(ISD::SINT_TO_FP, N->getDebugLoc(), VT, N0); } + // fold (uint_to_fp (setcc x, y, cc)) -> (select_cc x, y, -1.0, 0.0,, cc) + if (N0.getOpcode() == ISD::SETCC && !VT.isVector() && + (!LegalOperations || + TLI.isOperationLegalOrCustom(llvm::ISD::ConstantFP, VT))) { + SDValue Ops[] = + { N0.getOperand(0), N0.getOperand(1), + DAG.getConstantFP(1.0, VT), DAG.getConstantFP(0.0, VT), + N0.getOperand(2) }; + return DAG.getNode(ISD::SELECT_CC, N->getDebugLoc(), VT, Ops, 5); + } + + return SDValue(); } -- cgit v1.2.3