From 36c826ad958f74e1078cbe2ecfd07ae0a7170543 Mon Sep 17 00:00:00 2001 From: Anton Korobeynikov Date: Mon, 26 Jan 2009 19:26:01 +0000 Subject: [PATCH] During bittest switch lowering emit shift in the test block, which should (theoretically) allow us to generate more efficient code. We don't do this now though :) git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63027 91177308-0d34-0410-b5e6-96231b3b80d8 --- .../SelectionDAG/SelectionDAGBuild.cpp | 20 +++++++++---------- 1 file changed, 9 insertions(+), 11 deletions(-) diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp index f971069e82f..c467d9c3cb4 100644 --- a/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp +++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp @@ -1416,14 +1416,8 @@ void SelectionDAGLowering::visitBitTestHeader(BitTestBlock &B) { else ShiftOp = DAG.getNode(ISD::ZERO_EXTEND, TLI.getShiftAmountTy(), SUB); - // Make desired shift - SDValue SwitchVal = DAG.getNode(ISD::SHL, TLI.getPointerTy(), - DAG.getConstant(1, TLI.getPointerTy()), - ShiftOp); - - unsigned SwitchReg = FuncInfo.MakeReg(TLI.getPointerTy()); - SDValue CopyTo = DAG.getCopyToReg(getControlRoot(), SwitchReg, SwitchVal); - B.Reg = SwitchReg; + B.Reg = FuncInfo.MakeReg(TLI.getShiftAmountTy()); + SDValue CopyTo = DAG.getCopyToReg(getControlRoot(), B.Reg, ShiftOp); // Set NextBlock to be the MBB immediately after the current one, if any. // This is used to avoid emitting unnecessary branches to the next block. @@ -1453,10 +1447,14 @@ void SelectionDAGLowering::visitBitTestHeader(BitTestBlock &B) { void SelectionDAGLowering::visitBitTestCase(MachineBasicBlock* NextMBB, unsigned Reg, BitTestCase &B) { - // Emit bit tests and jumps - SDValue SwitchVal = DAG.getCopyFromReg(getControlRoot(), Reg, - TLI.getPointerTy()); + // Make desired shift + SDValue ShiftOp = DAG.getCopyFromReg(getControlRoot(), Reg, + TLI.getShiftAmountTy()); + SDValue SwitchVal = DAG.getNode(ISD::SHL, TLI.getPointerTy(), + DAG.getConstant(1, TLI.getPointerTy()), + ShiftOp); + // Emit bit tests and jumps SDValue AndOp = DAG.getNode(ISD::AND, TLI.getPointerTy(), SwitchVal, DAG.getConstant(B.Mask, TLI.getPointerTy())); SDValue AndCmp = DAG.getSetCC(TLI.getSetCCResultType(AndOp.getValueType()),