diff options
Diffstat (limited to 'lib/CodeGen')
| -rw-r--r-- | lib/CodeGen/SelectionDAG/LegalizeDAG.cpp | 68 |
1 files changed, 54 insertions, 14 deletions
diff --git a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp index f50e5e7..9061ae9 100644 --- a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp +++ b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp @@ -96,7 +96,7 @@ private: ArrayRef<int> Mask) const; bool LegalizeSetCCCondCode(EVT VT, SDValue &LHS, SDValue &RHS, SDValue &CC, - SDLoc dl); + bool &NeedInvert, SDLoc dl); SDValue ExpandLibCall(RTLIB::Libcall LC, SDNode *Node, bool isSigned); SDValue ExpandLibCall(RTLIB::Libcall LC, EVT RetVT, const SDValue *Ops, @@ -1597,18 +1597,30 @@ void SelectionDAGLegalize::ExpandDYNAMIC_STACKALLOC(SDNode* Node, /// LegalizeSetCCCondCode - Legalize a SETCC with given LHS and RHS and /// condition code CC on the current target. +/// /// If the SETCC has been legalized using AND / OR, then the legalized node -/// will be stored in LHS. RHS and CC will be set to SDValue(). +/// will be stored in LHS. RHS and CC will be set to SDValue(). NeedInvert +/// will be set to false. +/// /// If the SETCC has been legalized by using getSetCCSwappedOperands(), -/// then the values of LHS and RHS will be swapped and CC will be set to the -/// new condition. +/// then the values of LHS and RHS will be swapped, CC will be set to the +/// new condition, and NeedInvert will be set to false. +/// +/// If the SETCC has been legalized using the inverse condcode, then LHS and +/// RHS will be unchanged, CC will set to the inverted condcode, and NeedInvert +/// will be set to true. The caller must invert the result of the SETCC with +/// SelectionDAG::getNOT() or take equivalent action to swap the effect of a +/// true/false result. +/// /// \returns true if the SetCC has been legalized, false if it hasn't. bool SelectionDAGLegalize::LegalizeSetCCCondCode(EVT VT, SDValue &LHS, SDValue &RHS, SDValue &CC, + bool &NeedInvert, SDLoc dl) { MVT OpVT = LHS.getSimpleValueType(); ISD::CondCode CCCode = cast<CondCodeSDNode>(CC)->get(); + NeedInvert = false; switch (TLI.getCondCodeAction(CCCode, OpVT)) { default: llvm_unreachable("Unknown condition code action!"); case TargetLowering::Legal: @@ -1661,11 +1673,21 @@ bool SelectionDAGLegalize::LegalizeSetCCCondCode(EVT VT, case ISD::SETGT: case ISD::SETGE: case ISD::SETLT: - case ISD::SETNE: - case ISD::SETEQ: // We only support using the inverted operation, which is computed above // and not a different manner of supporting expanding these cases. llvm_unreachable("Don't know how to expand this condition!"); + case ISD::SETNE: + case ISD::SETEQ: + // Try inverting the result of the inverse condition. + InvCC = CCCode == ISD::SETEQ ? ISD::SETNE : ISD::SETEQ; + if (TLI.isCondCodeLegal(InvCC, OpVT)) { + CC = DAG.getCondCode(InvCC); + NeedInvert = true; + return true; + } + // If inverting the condition didn't work then we have no means to expand + // the condition. + llvm_unreachable("Don't know how to expand this condition!"); } SDValue SetCC1, SetCC2; @@ -2783,6 +2805,7 @@ void SelectionDAGLegalize::ExpandNode(SDNode *Node) { SmallVector<SDValue, 8> Results; SDLoc dl(Node); SDValue Tmp1, Tmp2, Tmp3, Tmp4; + bool NeedInvert; switch (Node->getOpcode()) { case ISD::CTPOP: case ISD::CTLZ: @@ -3673,15 +3696,20 @@ void SelectionDAGLegalize::ExpandNode(SDNode *Node) { Tmp2 = Node->getOperand(1); Tmp3 = Node->getOperand(2); bool Legalized = LegalizeSetCCCondCode(Node->getValueType(0), Tmp1, Tmp2, - Tmp3, dl); + Tmp3, NeedInvert, dl); if (Legalized) { - // If we exapanded the SETCC by swapping LHS and RHS, create a new SETCC - // node. + // If we expanded the SETCC by swapping LHS and RHS, or by inverting the + // condition code, create a new SETCC node. if (Tmp3.getNode()) Tmp1 = DAG.getNode(ISD::SETCC, dl, Node->getValueType(0), Tmp1, Tmp2, Tmp3); + // If we expanded the SETCC by inverting the condition code, then wrap + // the existing SETCC in a NOT to restore the intended condition. + if (NeedInvert) + Tmp1 = DAG.getNOT(dl, Tmp1, Tmp1->getValueType(0)); + Results.push_back(Tmp1); break; } @@ -3736,11 +3764,18 @@ void SelectionDAGLegalize::ExpandNode(SDNode *Node) { if (!Legalized) { Legalized = LegalizeSetCCCondCode( - getSetCCResultType(Tmp1.getValueType()), Tmp1, Tmp2, CC, dl); + getSetCCResultType(Tmp1.getValueType()), Tmp1, Tmp2, CC, NeedInvert, + dl); assert(Legalized && "Can't legalize SELECT_CC with legal condition!"); - // If we exapanded the SETCC by swapping LHS and RHS, create a new - // SELECT_CC node. + + // If we expanded the SETCC by inverting the condition code, then swap + // the True/False operands to match. + if (NeedInvert) + std::swap(Tmp3, Tmp4); + + // If we expanded the SETCC by swapping LHS and RHS, or by inverting the + // condition code, create a new SELECT_CC node. if (CC.getNode()) { Tmp1 = DAG.getNode(ISD::SELECT_CC, dl, Node->getValueType(0), Tmp1, Tmp2, Tmp3, Tmp4, CC); @@ -3761,11 +3796,16 @@ void SelectionDAGLegalize::ExpandNode(SDNode *Node) { Tmp4 = Node->getOperand(1); // CC bool Legalized = LegalizeSetCCCondCode(getSetCCResultType( - Tmp2.getValueType()), Tmp2, Tmp3, Tmp4, dl); + Tmp2.getValueType()), Tmp2, Tmp3, Tmp4, NeedInvert, dl); (void)Legalized; assert(Legalized && "Can't legalize BR_CC with legal condition!"); - // If we exapanded the SETCC by swapping LHS and RHS, create a new BR_CC + // If we expanded the SETCC by inverting the condition code, then wrap + // the existing SETCC in a NOT to restore the intended condition. + if (NeedInvert) + Tmp4 = DAG.getNOT(dl, Tmp4, Tmp4->getValueType(0)); + + // If we expanded the SETCC by swapping LHS and RHS, create a new BR_CC // node. if (Tmp4.getNode()) { Tmp1 = DAG.getNode(ISD::BR_CC, dl, Node->getValueType(0), Tmp1, |