Add R600 backend
A new backend supporting AMD GPUs: Radeon HD2XXX - HD7XXX
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169915 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/R600/SIISelLowering.cpp b/lib/Target/R600/SIISelLowering.cpp
new file mode 100644
index 0000000..292ce85
--- /dev/null
+++ b/lib/Target/R600/SIISelLowering.cpp
@@ -0,0 +1,442 @@
+//===-- SIISelLowering.cpp - SI DAG Lowering Implementation ---------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+/// \file
+/// \brief Custom DAG lowering for SI
+//
+//===----------------------------------------------------------------------===//
+
+#include "SIISelLowering.h"
+#include "AMDIL.h"
+#include "AMDILIntrinsicInfo.h"
+#include "SIInstrInfo.h"
+#include "SIMachineFunctionInfo.h"
+#include "SIRegisterInfo.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/CodeGen/SelectionDAG.h"
+
+using namespace llvm;
+
+SITargetLowering::SITargetLowering(TargetMachine &TM) :
+ AMDGPUTargetLowering(TM),
+ TII(static_cast<const SIInstrInfo*>(TM.getInstrInfo())) {
+ addRegisterClass(MVT::v4f32, &AMDGPU::VReg_128RegClass);
+ addRegisterClass(MVT::f32, &AMDGPU::VReg_32RegClass);
+ addRegisterClass(MVT::i32, &AMDGPU::VReg_32RegClass);
+ addRegisterClass(MVT::i64, &AMDGPU::SReg_64RegClass);
+ addRegisterClass(MVT::i1, &AMDGPU::SCCRegRegClass);
+ addRegisterClass(MVT::i1, &AMDGPU::VCCRegRegClass);
+
+ addRegisterClass(MVT::v4i32, &AMDGPU::SReg_128RegClass);
+ addRegisterClass(MVT::v8i32, &AMDGPU::SReg_256RegClass);
+
+ computeRegisterProperties();
+
+ setOperationAction(ISD::AND, MVT::i1, Custom);
+
+ setOperationAction(ISD::ADD, MVT::i64, Legal);
+ setOperationAction(ISD::ADD, MVT::i32, Legal);
+
+ setOperationAction(ISD::BR_CC, MVT::i32, Custom);
+
+ setOperationAction(ISD::INTRINSIC_WO_CHAIN, MVT::Other, Custom);
+
+ // We need to custom lower loads from the USER_SGPR address space, so we can
+ // add the SGPRs as livein registers.
+ setOperationAction(ISD::LOAD, MVT::i32, Custom);
+ setOperationAction(ISD::LOAD, MVT::i64, Custom);
+
+ setOperationAction(ISD::SELECT_CC, MVT::f32, Custom);
+ setOperationAction(ISD::SELECT_CC, MVT::i32, Custom);
+
+ setOperationAction(ISD::SELECT_CC, MVT::Other, Expand);
+ setTargetDAGCombine(ISD::SELECT_CC);
+
+ setTargetDAGCombine(ISD::SETCC);
+}
+
+MachineBasicBlock * SITargetLowering::EmitInstrWithCustomInserter(
+ MachineInstr * MI, MachineBasicBlock * BB) const {
+ const TargetInstrInfo * TII = getTargetMachine().getInstrInfo();
+ MachineRegisterInfo & MRI = BB->getParent()->getRegInfo();
+ MachineBasicBlock::iterator I = MI;
+
+ if (TII->get(MI->getOpcode()).TSFlags & SIInstrFlags::NEED_WAIT) {
+ AppendS_WAITCNT(MI, *BB, llvm::next(I));
+ return BB;
+ }
+
+ switch (MI->getOpcode()) {
+ default:
+ return AMDGPUTargetLowering::EmitInstrWithCustomInserter(MI, BB);
+ case AMDGPU::BRANCH: return BB;
+ case AMDGPU::CLAMP_SI:
+ BuildMI(*BB, I, BB->findDebugLoc(I), TII->get(AMDGPU::V_MOV_B32_e64))
+ .addOperand(MI->getOperand(0))
+ .addOperand(MI->getOperand(1))
+ // VSRC1-2 are unused, but we still need to fill all the
+ // operand slots, so we just reuse the VSRC0 operand
+ .addOperand(MI->getOperand(1))
+ .addOperand(MI->getOperand(1))
+ .addImm(0) // ABS
+ .addImm(1) // CLAMP
+ .addImm(0) // OMOD
+ .addImm(0); // NEG
+ MI->eraseFromParent();
+ break;
+
+ case AMDGPU::FABS_SI:
+ BuildMI(*BB, I, BB->findDebugLoc(I), TII->get(AMDGPU::V_MOV_B32_e64))
+ .addOperand(MI->getOperand(0))
+ .addOperand(MI->getOperand(1))
+ // VSRC1-2 are unused, but we still need to fill all the
+ // operand slots, so we just reuse the VSRC0 operand
+ .addOperand(MI->getOperand(1))
+ .addOperand(MI->getOperand(1))
+ .addImm(1) // ABS
+ .addImm(0) // CLAMP
+ .addImm(0) // OMOD
+ .addImm(0); // NEG
+ MI->eraseFromParent();
+ break;
+
+ case AMDGPU::FNEG_SI:
+ BuildMI(*BB, I, BB->findDebugLoc(I), TII->get(AMDGPU::V_MOV_B32_e64))
+ .addOperand(MI->getOperand(0))
+ .addOperand(MI->getOperand(1))
+ // VSRC1-2 are unused, but we still need to fill all the
+ // operand slots, so we just reuse the VSRC0 operand
+ .addOperand(MI->getOperand(1))
+ .addOperand(MI->getOperand(1))
+ .addImm(0) // ABS
+ .addImm(0) // CLAMP
+ .addImm(0) // OMOD
+ .addImm(1); // NEG
+ MI->eraseFromParent();
+ break;
+ case AMDGPU::SHADER_TYPE:
+ BB->getParent()->getInfo<SIMachineFunctionInfo>()->ShaderType =
+ MI->getOperand(0).getImm();
+ MI->eraseFromParent();
+ break;
+
+ case AMDGPU::SI_INTERP:
+ LowerSI_INTERP(MI, *BB, I, MRI);
+ break;
+ case AMDGPU::SI_INTERP_CONST:
+ LowerSI_INTERP_CONST(MI, *BB, I, MRI);
+ break;
+ case AMDGPU::SI_KIL:
+ LowerSI_KIL(MI, *BB, I, MRI);
+ break;
+ case AMDGPU::SI_WQM:
+ LowerSI_WQM(MI, *BB, I, MRI);
+ break;
+ case AMDGPU::SI_V_CNDLT:
+ LowerSI_V_CNDLT(MI, *BB, I, MRI);
+ break;
+ }
+ return BB;
+}
+
+void SITargetLowering::AppendS_WAITCNT(MachineInstr *MI, MachineBasicBlock &BB,
+ MachineBasicBlock::iterator I) const {
+ BuildMI(BB, I, BB.findDebugLoc(I), TII->get(AMDGPU::S_WAITCNT))
+ .addImm(0);
+}
+
+
+void SITargetLowering::LowerSI_WQM(MachineInstr *MI, MachineBasicBlock &BB,
+ MachineBasicBlock::iterator I, MachineRegisterInfo & MRI) const {
+ BuildMI(BB, I, BB.findDebugLoc(I), TII->get(AMDGPU::S_WQM_B64), AMDGPU::EXEC)
+ .addReg(AMDGPU::EXEC);
+
+ MI->eraseFromParent();
+}
+
+void SITargetLowering::LowerSI_INTERP(MachineInstr *MI, MachineBasicBlock &BB,
+ MachineBasicBlock::iterator I, MachineRegisterInfo & MRI) const {
+ unsigned tmp = MRI.createVirtualRegister(&AMDGPU::VReg_32RegClass);
+ unsigned M0 = MRI.createVirtualRegister(&AMDGPU::M0RegRegClass);
+ MachineOperand dst = MI->getOperand(0);
+ MachineOperand iReg = MI->getOperand(1);
+ MachineOperand jReg = MI->getOperand(2);
+ MachineOperand attr_chan = MI->getOperand(3);
+ MachineOperand attr = MI->getOperand(4);
+ MachineOperand params = MI->getOperand(5);
+
+ BuildMI(BB, I, BB.findDebugLoc(I), TII->get(AMDGPU::S_MOV_B32), M0)
+ .addOperand(params);
+
+ BuildMI(BB, I, BB.findDebugLoc(I), TII->get(AMDGPU::V_INTERP_P1_F32), tmp)
+ .addOperand(iReg)
+ .addOperand(attr_chan)
+ .addOperand(attr)
+ .addReg(M0);
+
+ BuildMI(BB, I, BB.findDebugLoc(I), TII->get(AMDGPU::V_INTERP_P2_F32))
+ .addOperand(dst)
+ .addReg(tmp)
+ .addOperand(jReg)
+ .addOperand(attr_chan)
+ .addOperand(attr)
+ .addReg(M0);
+
+ MI->eraseFromParent();
+}
+
+void SITargetLowering::LowerSI_INTERP_CONST(MachineInstr *MI,
+ MachineBasicBlock &BB, MachineBasicBlock::iterator I,
+ MachineRegisterInfo &MRI) const {
+ MachineOperand dst = MI->getOperand(0);
+ MachineOperand attr_chan = MI->getOperand(1);
+ MachineOperand attr = MI->getOperand(2);
+ MachineOperand params = MI->getOperand(3);
+ unsigned M0 = MRI.createVirtualRegister(&AMDGPU::M0RegRegClass);
+
+ BuildMI(BB, I, BB.findDebugLoc(I), TII->get(AMDGPU::S_MOV_B32), M0)
+ .addOperand(params);
+
+ BuildMI(BB, I, BB.findDebugLoc(I), TII->get(AMDGPU::V_INTERP_MOV_F32))
+ .addOperand(dst)
+ .addOperand(attr_chan)
+ .addOperand(attr)
+ .addReg(M0);
+
+ MI->eraseFromParent();
+}
+
+void SITargetLowering::LowerSI_KIL(MachineInstr *MI, MachineBasicBlock &BB,
+ MachineBasicBlock::iterator I, MachineRegisterInfo & MRI) const {
+ // Clear this pixel from the exec mask if the operand is negative
+ BuildMI(BB, I, BB.findDebugLoc(I), TII->get(AMDGPU::V_CMPX_LE_F32_e32),
+ AMDGPU::VCC)
+ .addReg(AMDGPU::SREG_LIT_0)
+ .addOperand(MI->getOperand(0));
+
+ MI->eraseFromParent();
+}
+
+void SITargetLowering::LowerSI_V_CNDLT(MachineInstr *MI, MachineBasicBlock &BB,
+ MachineBasicBlock::iterator I, MachineRegisterInfo & MRI) const {
+ unsigned VCC = MRI.createVirtualRegister(&AMDGPU::SReg_64RegClass);
+
+ BuildMI(BB, I, BB.findDebugLoc(I),
+ TII->get(AMDGPU::V_CMP_GT_F32_e32),
+ VCC)
+ .addReg(AMDGPU::SREG_LIT_0)
+ .addOperand(MI->getOperand(1));
+
+ BuildMI(BB, I, BB.findDebugLoc(I), TII->get(AMDGPU::V_CNDMASK_B32_e32))
+ .addOperand(MI->getOperand(0))
+ .addOperand(MI->getOperand(3))
+ .addOperand(MI->getOperand(2))
+ .addReg(VCC);
+
+ MI->eraseFromParent();
+}
+
+EVT SITargetLowering::getSetCCResultType(EVT VT) const {
+ return MVT::i1;
+}
+
+//===----------------------------------------------------------------------===//
+// Custom DAG Lowering Operations
+//===----------------------------------------------------------------------===//
+
+SDValue SITargetLowering::LowerOperation(SDValue Op, SelectionDAG &DAG) const {
+ switch (Op.getOpcode()) {
+ default: return AMDGPUTargetLowering::LowerOperation(Op, DAG);
+ case ISD::BR_CC: return LowerBR_CC(Op, DAG);
+ case ISD::LOAD: return LowerLOAD(Op, DAG);
+ case ISD::SELECT_CC: return LowerSELECT_CC(Op, DAG);
+ case ISD::AND: return Loweri1ContextSwitch(Op, DAG, ISD::AND);
+ case ISD::INTRINSIC_WO_CHAIN: {
+ unsigned IntrinsicID =
+ cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
+ EVT VT = Op.getValueType();
+ switch (IntrinsicID) {
+ case AMDGPUIntrinsic::SI_vs_load_buffer_index:
+ return CreateLiveInRegister(DAG, &AMDGPU::VReg_32RegClass,
+ AMDGPU::VGPR0, VT);
+ default: return AMDGPUTargetLowering::LowerOperation(Op, DAG);
+ }
+ break;
+ }
+ }
+ return SDValue();
+}
+
+/// \brief The function is for lowering i1 operations on the
+/// VCC register.
+///
+/// In the VALU context, VCC is a one bit register, but in the
+/// SALU context the VCC is a 64-bit register (1-bit per thread). Since only
+/// the SALU can perform operations on the VCC register, we need to promote
+/// the operand types from i1 to i64 in order for tablegen to be able to match
+/// this operation to the correct SALU instruction. We do this promotion by
+/// wrapping the operands in a CopyToReg node.
+///
+SDValue SITargetLowering::Loweri1ContextSwitch(SDValue Op,
+ SelectionDAG &DAG,
+ unsigned VCCNode) const {
+ DebugLoc DL = Op.getDebugLoc();
+
+ SDValue OpNode = DAG.getNode(VCCNode, DL, MVT::i64,
+ DAG.getNode(SIISD::VCC_BITCAST, DL, MVT::i64,
+ Op.getOperand(0)),
+ DAG.getNode(SIISD::VCC_BITCAST, DL, MVT::i64,
+ Op.getOperand(1)));
+
+ return DAG.getNode(SIISD::VCC_BITCAST, DL, MVT::i1, OpNode);
+}
+
+SDValue SITargetLowering::LowerBR_CC(SDValue Op, SelectionDAG &DAG) const {
+ SDValue Chain = Op.getOperand(0);
+ SDValue CC = Op.getOperand(1);
+ SDValue LHS = Op.getOperand(2);
+ SDValue RHS = Op.getOperand(3);
+ SDValue JumpT = Op.getOperand(4);
+ SDValue CmpValue;
+ SDValue Result;
+ CmpValue = DAG.getNode(
+ ISD::SETCC,
+ Op.getDebugLoc(),
+ MVT::i1,
+ LHS, RHS,
+ CC);
+
+ Result = DAG.getNode(
+ AMDGPUISD::BRANCH_COND,
+ CmpValue.getDebugLoc(),
+ MVT::Other, Chain,
+ JumpT, CmpValue);
+ return Result;
+}
+
+SDValue SITargetLowering::LowerLOAD(SDValue Op, SelectionDAG &DAG) const {
+ EVT VT = Op.getValueType();
+ LoadSDNode *Ptr = dyn_cast<LoadSDNode>(Op);
+
+ assert(Ptr);
+
+ unsigned AddrSpace = Ptr->getPointerInfo().getAddrSpace();
+
+ // We only need to lower USER_SGPR address space loads
+ if (AddrSpace != AMDGPUAS::USER_SGPR_ADDRESS) {
+ return SDValue();
+ }
+
+ // Loads from the USER_SGPR address space can only have constant value
+ // pointers.
+ ConstantSDNode *BasePtr = dyn_cast<ConstantSDNode>(Ptr->getBasePtr());
+ assert(BasePtr);
+
+ unsigned TypeDwordWidth = VT.getSizeInBits() / 32;
+ const TargetRegisterClass * dstClass;
+ switch (TypeDwordWidth) {
+ default:
+ assert(!"USER_SGPR value size not implemented");
+ return SDValue();
+ case 1:
+ dstClass = &AMDGPU::SReg_32RegClass;
+ break;
+ case 2:
+ dstClass = &AMDGPU::SReg_64RegClass;
+ break;
+ }
+ uint64_t Index = BasePtr->getZExtValue();
+ assert(Index % TypeDwordWidth == 0 && "USER_SGPR not properly aligned");
+ unsigned SGPRIndex = Index / TypeDwordWidth;
+ unsigned Reg = dstClass->getRegister(SGPRIndex);
+
+ DAG.ReplaceAllUsesOfValueWith(Op, CreateLiveInRegister(DAG, dstClass, Reg,
+ VT));
+ return SDValue();
+}
+
+SDValue SITargetLowering::LowerSELECT_CC(SDValue Op, SelectionDAG &DAG) const {
+ SDValue LHS = Op.getOperand(0);
+ SDValue RHS = Op.getOperand(1);
+ SDValue True = Op.getOperand(2);
+ SDValue False = Op.getOperand(3);
+ SDValue CC = Op.getOperand(4);
+ EVT VT = Op.getValueType();
+ DebugLoc DL = Op.getDebugLoc();
+
+ // Possible Min/Max pattern
+ SDValue MinMax = LowerMinMax(Op, DAG);
+ if (MinMax.getNode()) {
+ return MinMax;
+ }
+
+ SDValue Cond = DAG.getNode(ISD::SETCC, DL, MVT::i1, LHS, RHS, CC);
+ return DAG.getNode(ISD::SELECT, DL, VT, Cond, True, False);
+}
+
+//===----------------------------------------------------------------------===//
+// Custom DAG optimizations
+//===----------------------------------------------------------------------===//
+
+SDValue SITargetLowering::PerformDAGCombine(SDNode *N,
+ DAGCombinerInfo &DCI) const {
+ SelectionDAG &DAG = DCI.DAG;
+ DebugLoc DL = N->getDebugLoc();
+ EVT VT = N->getValueType(0);
+
+ switch (N->getOpcode()) {
+ default: break;
+ case ISD::SELECT_CC: {
+ N->dump();
+ ConstantSDNode *True, *False;
+ // i1 selectcc(l, r, -1, 0, cc) -> i1 setcc(l, r, cc)
+ if ((True = dyn_cast<ConstantSDNode>(N->getOperand(2)))
+ && (False = dyn_cast<ConstantSDNode>(N->getOperand(3)))
+ && True->isAllOnesValue()
+ && False->isNullValue()
+ && VT == MVT::i1) {
+ return DAG.getNode(ISD::SETCC, DL, VT, N->getOperand(0),
+ N->getOperand(1), N->getOperand(4));
+
+ }
+ break;
+ }
+ case ISD::SETCC: {
+ SDValue Arg0 = N->getOperand(0);
+ SDValue Arg1 = N->getOperand(1);
+ SDValue CC = N->getOperand(2);
+ ConstantSDNode * C = NULL;
+ ISD::CondCode CCOp = dyn_cast<CondCodeSDNode>(CC)->get();
+
+ // i1 setcc (sext(i1), 0, setne) -> i1 setcc(i1, 0, setne)
+ if (VT == MVT::i1
+ && Arg0.getOpcode() == ISD::SIGN_EXTEND
+ && Arg0.getOperand(0).getValueType() == MVT::i1
+ && (C = dyn_cast<ConstantSDNode>(Arg1))
+ && C->isNullValue()
+ && CCOp == ISD::SETNE) {
+ return SimplifySetCC(VT, Arg0.getOperand(0),
+ DAG.getConstant(0, MVT::i1), CCOp, true, DCI, DL);
+ }
+ break;
+ }
+ }
+ return SDValue();
+}
+
+#define NODE_NAME_CASE(node) case SIISD::node: return #node;
+
+const char* SITargetLowering::getTargetNodeName(unsigned Opcode) const {
+ switch (Opcode) {
+ default: return AMDGPUTargetLowering::getTargetNodeName(Opcode);
+ NODE_NAME_CASE(VCC_AND)
+ NODE_NAME_CASE(VCC_BITCAST)
+ }
+}