src/gallium/drivers/radeon/AMDGPUISelLowering.cpp

   1 //===-- AMDGPUISelLowering.cpp - AMDGPU Common DAG lowering functions -----===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This is the parent TargetLowering class for hardware code gen targets.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "AMDGPUISelLowering.h"
  15 #include "AMDILIntrinsicInfo.h"
  16 #include "AMDGPUUtil.h"
  17 #include "llvm/CodeGen/MachineRegisterInfo.h"
  18
  19 using namespace llvm;
  20
  21 AMDGPUTargetLowering::AMDGPUTargetLowering(TargetMachine &TM) :
  22   AMDILTargetLowering(TM)
  23 {
  24   // We need to custom lower some of the intrinsics
  25   setOperationAction(ISD::INTRINSIC_WO_CHAIN, MVT::Other, Custom);
  26 }
  27
  28 SDValue AMDGPUTargetLowering::LowerOperation(SDValue Op, SelectionDAG &DAG)
  29     const
  30 {
  31   switch (Op.getOpcode()) {
  32   default: return AMDILTargetLowering::LowerOperation(Op, DAG);
  33   case ISD::INTRINSIC_WO_CHAIN: return LowerINTRINSIC_WO_CHAIN(Op, DAG);
  34   }
  35 }
  36
  37 SDValue AMDGPUTargetLowering::LowerINTRINSIC_WO_CHAIN(SDValue Op,
  38     SelectionDAG &DAG) const
  39 {
  40   unsigned IntrinsicID = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
  41   DebugLoc DL = Op.getDebugLoc();
  42   EVT VT = Op.getValueType();
  43
  44   switch (IntrinsicID) {
  45     default: return Op;
  46     case AMDGPUIntrinsic::AMDIL_abs:
  47       return LowerIntrinsicIABS(Op, DAG);
  48     case AMDGPUIntrinsic::AMDIL_max:
  49       return DAG.getNode(AMDGPUISD::FMAX, DL, VT, Op.getOperand(1),
  50                                                   Op.getOperand(2));
  51     case AMDGPUIntrinsic::AMDGPU_imax:
  52       return DAG.getNode(AMDGPUISD::SMAX, DL, VT, Op.getOperand(1),
  53                                                   Op.getOperand(2));
  54     case AMDGPUIntrinsic::AMDGPU_umax:
  55       return DAG.getNode(AMDGPUISD::UMAX, DL, VT, Op.getOperand(1),
  56                                                   Op.getOperand(2));
  57   }
  58 }
  59
  60 ///IABS(a) = SMAX(sub(0, a), a)
  61 SDValue AMDGPUTargetLowering::LowerIntrinsicIABS(SDValue Op,
  62     SelectionDAG &DAG) const
  63 {
  64
  65   DebugLoc DL = Op.getDebugLoc();
  66   EVT VT = Op.getValueType();
  67   SDValue Neg = DAG.getNode(ISD::SUB, DL, VT, DAG.getConstant(0, VT),
  68                                               Op.getOperand(1));
  69
  70   return DAG.getNode(AMDGPUISD::SMAX, DL, VT, Neg, Op.getOperand(1));
  71 }
  72
  73 void AMDGPUTargetLowering::addLiveIn(MachineInstr * MI,
  74     MachineFunction * MF, MachineRegisterInfo & MRI,
  75     const TargetInstrInfo * TII, unsigned reg) const
  76 {
  77   AMDGPU::utilAddLiveIn(MF, MRI, TII, reg, MI->getOperand(0).getReg());
  78 }
  79
  80 #define NODE_NAME_CASE(node) case AMDGPUISD::node: return #node;
  81
  82 const char* AMDGPUTargetLowering::getTargetNodeName(unsigned Opcode) const
  83 {
  84   switch (Opcode) {
  85   default: return AMDILTargetLowering::getTargetNodeName(Opcode);
  86
  87   NODE_NAME_CASE(FMAX)
  88   NODE_NAME_CASE(SMAX)
  89   NODE_NAME_CASE(UMAX)
  90   }
  91 }