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Diffstat (limited to 'lib/Target/MBlaze/MBlazeISelLowering.cpp')
| -rw-r--r-- | lib/Target/MBlaze/MBlazeISelLowering.cpp | 975 |
1 files changed, 975 insertions, 0 deletions
diff --git a/lib/Target/MBlaze/MBlazeISelLowering.cpp b/lib/Target/MBlaze/MBlazeISelLowering.cpp new file mode 100644 index 0000000000..f0864d0f49 --- /dev/null +++ b/lib/Target/MBlaze/MBlazeISelLowering.cpp @@ -0,0 +1,975 @@ +//===-- MBlazeISelLowering.cpp - MBlaze DAG Lowering Implementation -------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file defines the interfaces that MBlaze uses to lower LLVM code into a +// selection DAG. +// +//===----------------------------------------------------------------------===// + +#define DEBUG_TYPE "mblaze-lower" +#include "MBlazeISelLowering.h" +#include "MBlazeMachineFunction.h" +#include "MBlazeTargetMachine.h" +#include "MBlazeTargetObjectFile.h" +#include "MBlazeSubtarget.h" +#include "llvm/DerivedTypes.h" +#include "llvm/Function.h" +#include "llvm/GlobalVariable.h" +#include "llvm/Intrinsics.h" +#include "llvm/CallingConv.h" +#include "llvm/CodeGen/CallingConvLower.h" +#include "llvm/CodeGen/MachineFrameInfo.h" +#include "llvm/CodeGen/MachineFunction.h" +#include "llvm/CodeGen/MachineInstrBuilder.h" +#include "llvm/CodeGen/MachineRegisterInfo.h" +#include "llvm/CodeGen/SelectionDAGISel.h" +#include "llvm/CodeGen/ValueTypes.h" +#include "llvm/Support/Debug.h" +#include "llvm/Support/ErrorHandling.h" +#include "llvm/Support/raw_ostream.h" +using namespace llvm; + +const char *MBlazeTargetLowering::getTargetNodeName(unsigned Opcode) const { + switch (Opcode) { + case MBlazeISD::JmpLink : return "MBlazeISD::JmpLink"; + case MBlazeISD::GPRel : return "MBlazeISD::GPRel"; + case MBlazeISD::Wrap : return "MBlazeISD::Wrap"; + case MBlazeISD::ICmp : return "MBlazeISD::ICmp"; + case MBlazeISD::Ret : return "MBlazeISD::Ret"; + case MBlazeISD::Select_CC : return "MBlazeISD::Select_CC"; + default : return NULL; + } +} + +MBlazeTargetLowering::MBlazeTargetLowering(MBlazeTargetMachine &TM) + : TargetLowering(TM, new MBlazeTargetObjectFile()) { + Subtarget = &TM.getSubtarget<MBlazeSubtarget>(); + + // MBlaze does not have i1 type, so use i32 for + // setcc operations results (slt, sgt, ...). + setBooleanContents(ZeroOrOneBooleanContent); + + // Set up the register classes + addRegisterClass(MVT::i32, MBlaze::CPURegsRegisterClass); + if (Subtarget->hasFPU()) { + addRegisterClass(MVT::f32, MBlaze::FGR32RegisterClass); + setOperationAction(ISD::ConstantFP, MVT::f32, Legal); + } + + // Floating point operations which are not supported + setOperationAction(ISD::FREM, MVT::f32, Expand); + setOperationAction(ISD::UINT_TO_FP, MVT::i8, Expand); + setOperationAction(ISD::UINT_TO_FP, MVT::i16, Expand); + setOperationAction(ISD::UINT_TO_FP, MVT::i32, Expand); + setOperationAction(ISD::FP_TO_UINT, MVT::i32, Expand); + setOperationAction(ISD::FP_ROUND, MVT::f32, Expand); + setOperationAction(ISD::FP_ROUND, MVT::f64, Expand); + setOperationAction(ISD::FCOPYSIGN, MVT::f32, Expand); + setOperationAction(ISD::FCOPYSIGN, MVT::f64, Expand); + setOperationAction(ISD::FSIN, MVT::f32, Expand); + setOperationAction(ISD::FCOS, MVT::f32, Expand); + setOperationAction(ISD::FPOWI, MVT::f32, Expand); + setOperationAction(ISD::FPOW, MVT::f32, Expand); + setOperationAction(ISD::FLOG, MVT::f32, Expand); + setOperationAction(ISD::FLOG2, MVT::f32, Expand); + setOperationAction(ISD::FLOG10, MVT::f32, Expand); + setOperationAction(ISD::FEXP, MVT::f32, Expand); + + // Load extented operations for i1 types must be promoted + setLoadExtAction(ISD::EXTLOAD, MVT::i1, Promote); + setLoadExtAction(ISD::ZEXTLOAD, MVT::i1, Promote); + setLoadExtAction(ISD::SEXTLOAD, MVT::i1, Promote); + + // MBlaze has no REM or DIVREM operations. + setOperationAction(ISD::UREM, MVT::i32, Expand); + setOperationAction(ISD::SREM, MVT::i32, Expand); + setOperationAction(ISD::SDIVREM, MVT::i32, Expand); + setOperationAction(ISD::UDIVREM, MVT::i32, Expand); + + // If the processor doesn't support multiply then expand it + if (!Subtarget->hasMul()) { + setOperationAction(ISD::MUL, MVT::i32, Expand); + } + + // If the processor doesn't support 64-bit multiply then expand + if (!Subtarget->hasMul() || !Subtarget->hasMul64()) { + setOperationAction(ISD::MULHS, MVT::i32, Expand); + setOperationAction(ISD::MULHS, MVT::i64, Expand); + setOperationAction(ISD::MULHU, MVT::i32, Expand); + setOperationAction(ISD::MULHU, MVT::i64, Expand); + } + + // If the processor doesn't support division then expand + if (!Subtarget->hasDiv()) { + setOperationAction(ISD::UDIV, MVT::i32, Expand); + setOperationAction(ISD::SDIV, MVT::i32, Expand); + } + + // Expand unsupported conversions + setOperationAction(ISD::BIT_CONVERT, MVT::f32, Expand); + setOperationAction(ISD::BIT_CONVERT, MVT::i32, Expand); + + // Expand SELECT_CC + setOperationAction(ISD::SELECT_CC, MVT::Other, Expand); + + // MBlaze doesn't have MUL_LOHI + setOperationAction(ISD::SMUL_LOHI, MVT::i32, Expand); + setOperationAction(ISD::UMUL_LOHI, MVT::i32, Expand); + setOperationAction(ISD::SMUL_LOHI, MVT::i64, Expand); + setOperationAction(ISD::UMUL_LOHI, MVT::i64, Expand); + + // Used by legalize types to correctly generate the setcc result. + // Without this, every float setcc comes with a AND/OR with the result, + // we don't want this, since the fpcmp result goes to a flag register, + // which is used implicitly by brcond and select operations. + AddPromotedToType(ISD::SETCC, MVT::i1, MVT::i32); + AddPromotedToType(ISD::SELECT, MVT::i1, MVT::i32); + AddPromotedToType(ISD::SELECT_CC, MVT::i1, MVT::i32); + + // MBlaze Custom Operations + setOperationAction(ISD::GlobalAddress, MVT::i32, Custom); + setOperationAction(ISD::GlobalTLSAddress, MVT::i32, Custom); + setOperationAction(ISD::JumpTable, MVT::i32, Custom); + setOperationAction(ISD::ConstantPool, MVT::i32, Custom); + + // Variable Argument support + setOperationAction(ISD::VASTART, MVT::Other, Custom); + setOperationAction(ISD::VAEND, MVT::Other, Expand); + setOperationAction(ISD::VAARG, MVT::Other, Expand); + setOperationAction(ISD::VACOPY, MVT::Other, Expand); + + + // Operations not directly supported by MBlaze. + setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32, Expand); + setOperationAction(ISD::BR_JT, MVT::Other, Expand); + setOperationAction(ISD::BR_CC, MVT::Other, Expand); + setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i1, Expand); + setOperationAction(ISD::ROTL, MVT::i32, Expand); + setOperationAction(ISD::ROTR, MVT::i32, Expand); + setOperationAction(ISD::SHL_PARTS, MVT::i32, Expand); + setOperationAction(ISD::SRA_PARTS, MVT::i32, Expand); + setOperationAction(ISD::SRL_PARTS, MVT::i32, Expand); + setOperationAction(ISD::CTLZ, MVT::i32, Expand); + setOperationAction(ISD::CTTZ, MVT::i32, Expand); + setOperationAction(ISD::CTPOP, MVT::i32, Expand); + setOperationAction(ISD::BSWAP, MVT::i32, Expand); + + // We don't have line number support yet. + setOperationAction(ISD::EH_LABEL, MVT::Other, Expand); + + // Use the default for now + setOperationAction(ISD::STACKSAVE, MVT::Other, Expand); + setOperationAction(ISD::STACKRESTORE, MVT::Other, Expand); + setOperationAction(ISD::MEMBARRIER, MVT::Other, Expand); + + // MBlaze doesn't have extending float->double load/store + setLoadExtAction(ISD::EXTLOAD, MVT::f32, Expand); + setTruncStoreAction(MVT::f64, MVT::f32, Expand); + + setStackPointerRegisterToSaveRestore(MBlaze::R1); + computeRegisterProperties(); +} + +MVT::SimpleValueType MBlazeTargetLowering::getSetCCResultType(EVT VT) const { + return MVT::i32; +} + +/// getFunctionAlignment - Return the Log2 alignment of this function. +unsigned MBlazeTargetLowering::getFunctionAlignment(const Function *) const { + return 2; +} + +SDValue MBlazeTargetLowering::LowerOperation(SDValue Op, SelectionDAG &DAG) { + switch (Op.getOpcode()) + { + case ISD::ConstantPool: return LowerConstantPool(Op, DAG); + case ISD::GlobalAddress: return LowerGlobalAddress(Op, DAG); + case ISD::GlobalTLSAddress: return LowerGlobalTLSAddress(Op, DAG); + case ISD::JumpTable: return LowerJumpTable(Op, DAG); + case ISD::SELECT_CC: return LowerSELECT_CC(Op, DAG); + case ISD::VASTART: return LowerVASTART(Op, DAG); + } + return SDValue(); +} + +//===----------------------------------------------------------------------===// +// Lower helper functions +//===----------------------------------------------------------------------===// +MachineBasicBlock* MBlazeTargetLowering:: +EmitInstrWithCustomInserter(MachineInstr *MI, MachineBasicBlock *BB, + DenseMap<MachineBasicBlock*, + MachineBasicBlock*> *EM) const { + const TargetInstrInfo *TII = getTargetMachine().getInstrInfo(); + DebugLoc dl = MI->getDebugLoc(); + + switch (MI->getOpcode()) { + default: assert(false && "Unexpected instr type to insert"); + case MBlaze::ShiftRL: + case MBlaze::ShiftRA: + case MBlaze::ShiftL: { + // To "insert" a shift left instruction, we actually have to insert a + // simple loop. The incoming instruction knows the destination vreg to + // set, the source vreg to operate over and the shift amount. + const BasicBlock *LLVM_BB = BB->getBasicBlock(); + MachineFunction::iterator It = BB; + ++It; + + // start: + // andi samt, samt, 31 + // beqid samt, finish + // add dst, src, r0 + // loop: + // addik samt, samt, -1 + // sra dst, dst + // bneid samt, loop + // nop + // finish: + MachineFunction *F = BB->getParent(); + MachineRegisterInfo &R = F->getRegInfo(); + MachineBasicBlock *loop = F->CreateMachineBasicBlock(LLVM_BB); + MachineBasicBlock *finish = F->CreateMachineBasicBlock(LLVM_BB); + + unsigned IAMT = R.createVirtualRegister(MBlaze::CPURegsRegisterClass); + BuildMI(BB, dl, TII->get(MBlaze::ANDI), IAMT) + .addReg(MI->getOperand(2).getReg()) + .addImm(31); + + unsigned IVAL = R.createVirtualRegister(MBlaze::CPURegsRegisterClass); + BuildMI(BB, dl, TII->get(MBlaze::ADDI), IVAL) + .addReg(MI->getOperand(1).getReg()) + .addImm(0); + + BuildMI(BB, dl, TII->get(MBlaze::BEQID)) + .addReg(IAMT) + .addMBB(finish); + + F->insert(It, loop); + F->insert(It, finish); + + // Update machine-CFG edges by first adding all successors of the current + // block to the new block which will contain the Phi node for the select. + // Also inform sdisel of the edge changes. + for(MachineBasicBlock::succ_iterator i = BB->succ_begin(), + e = BB->succ_end(); i != e; ++i) { + EM->insert(std::make_pair(*i, finish)); + finish->addSuccessor(*i); + } + + // Next, remove all successors of the current block, and add the true + // and fallthrough blocks as its successors. + while(!BB->succ_empty()) + BB->removeSuccessor(BB->succ_begin()); + BB->addSuccessor(loop); + BB->addSuccessor(finish); + + // Next, add the finish block as a successor of the loop block + loop->addSuccessor(finish); + loop->addSuccessor(loop); + + unsigned DST = R.createVirtualRegister(MBlaze::CPURegsRegisterClass); + unsigned NDST = R.createVirtualRegister(MBlaze::CPURegsRegisterClass); + BuildMI(loop, dl, TII->get(MBlaze::PHI), DST) + .addReg(IVAL).addMBB(BB) + .addReg(NDST).addMBB(loop); + + unsigned SAMT = R.createVirtualRegister(MBlaze::CPURegsRegisterClass); + unsigned NAMT = R.createVirtualRegister(MBlaze::CPURegsRegisterClass); + BuildMI(loop, dl, TII->get(MBlaze::PHI), SAMT) + .addReg(IAMT).addMBB(BB) + .addReg(NAMT).addMBB(loop); + + if (MI->getOpcode() == MBlaze::ShiftL) + BuildMI(loop, dl, TII->get(MBlaze::ADD), NDST).addReg(DST).addReg(DST); + else if (MI->getOpcode() == MBlaze::ShiftRA) + BuildMI(loop, dl, TII->get(MBlaze::SRA), NDST).addReg(DST); + else if (MI->getOpcode() == MBlaze::ShiftRL) + BuildMI(loop, dl, TII->get(MBlaze::SRL), NDST).addReg(DST); + else + llvm_unreachable( "Cannot lower unknown shift instruction" ); + + BuildMI(loop, dl, TII->get(MBlaze::ADDI), NAMT) + .addReg(SAMT) + .addImm(-1); + + BuildMI(loop, dl, TII->get(MBlaze::BNEID)) + .addReg(NAMT) + .addMBB(loop); + + BuildMI(finish, dl, TII->get(MBlaze::PHI), MI->getOperand(0).getReg()) + .addReg(IVAL).addMBB(BB) + .addReg(NDST).addMBB(loop); + + // The pseudo instruction is no longer needed so remove it + F->DeleteMachineInstr(MI); + return finish; + } + + case MBlaze::Select_FCC: + case MBlaze::Select_CC: { + // To "insert" a SELECT_CC instruction, we actually have to insert the + // diamond control-flow pattern. The incoming instruction knows the + // destination vreg to set, the condition code register to branch on, the + // true/false values to select between, and a branch opcode to use. + const BasicBlock *LLVM_BB = BB->getBasicBlock(); + MachineFunction::iterator It = BB; + ++It; + + // thisMBB: + // ... + // TrueVal = ... + // setcc r1, r2, r3 + // bNE r1, r0, copy1MBB + // fallthrough --> copy0MBB + MachineFunction *F = BB->getParent(); + MachineBasicBlock *flsBB = F->CreateMachineBasicBlock(LLVM_BB); + MachineBasicBlock *dneBB = F->CreateMachineBasicBlock(LLVM_BB); + + unsigned Opc; + switch (MI->getOperand(4).getImm()) { + default: llvm_unreachable( "Unknown branch condition" ); + case MBlazeCC::EQ: Opc = MBlaze::BNEID; break; + case MBlazeCC::NE: Opc = MBlaze::BEQID; break; + case MBlazeCC::GT: Opc = MBlaze::BLEID; break; + case MBlazeCC::LT: Opc = MBlaze::BGEID; break; + case MBlazeCC::GE: Opc = MBlaze::BLTID; break; + case MBlazeCC::LE: Opc = MBlaze::BGTID; break; + } + + BuildMI(BB, dl, TII->get(Opc)) + .addReg(MI->getOperand(3).getReg()) + .addMBB(dneBB); + + F->insert(It, flsBB); + F->insert(It, dneBB); + + // Update machine-CFG edges by first adding all successors of the current + // block to the new block which will contain the Phi node for the select. + // Also inform sdisel of the edge changes. + for(MachineBasicBlock::succ_iterator i = BB->succ_begin(), + e = BB->succ_end(); i != e; ++i) { + EM->insert(std::make_pair(*i, dneBB)); + dneBB->addSuccessor(*i); + } + + // Next, remove all successors of the current block, and add the true + // and fallthrough blocks as its successors. + while(!BB->succ_empty()) + BB->removeSuccessor(BB->succ_begin()); + BB->addSuccessor(flsBB); + BB->addSuccessor(dneBB); + flsBB->addSuccessor(dneBB); + + // sinkMBB: + // %Result = phi [ %FalseValue, copy0MBB ], [ %TrueValue, thisMBB ] + // ... + //BuildMI(dneBB, dl, TII->get(MBlaze::PHI), MI->getOperand(0).getReg()) + // .addReg(MI->getOperand(1).getReg()).addMBB(flsBB) + // .addReg(MI->getOperand(2).getReg()).addMBB(BB); + + BuildMI(dneBB, dl, TII->get(MBlaze::PHI), MI->getOperand(0).getReg()) + .addReg(MI->getOperand(2).getReg()).addMBB(flsBB) + .addReg(MI->getOperand(1).getReg()).addMBB(BB); + + F->DeleteMachineInstr(MI); // The pseudo instruction is gone now. + return dneBB; + } + } +} + +//===----------------------------------------------------------------------===// +// Misc Lower Operation implementation +//===----------------------------------------------------------------------===// +// + +SDValue MBlazeTargetLowering::LowerSELECT_CC(SDValue Op, SelectionDAG &DAG) { + SDValue LHS = Op.getOperand(0); + SDValue RHS = Op.getOperand(1); + SDValue TrueVal = Op.getOperand(2); + SDValue FalseVal = Op.getOperand(3); + DebugLoc dl = Op.getDebugLoc(); + unsigned Opc; + + SDValue CompareFlag; + if (LHS.getValueType() == MVT::i32) { + Opc = MBlazeISD::Select_CC; + CompareFlag = DAG.getNode(MBlazeISD::ICmp, dl, MVT::i32, LHS, RHS) + .getValue(1); + } else { + llvm_unreachable( "Cannot lower select_cc with unknown type" ); + } + + return DAG.getNode(Opc, dl, TrueVal.getValueType(), TrueVal, FalseVal, + CompareFlag); +} + +SDValue MBlazeTargetLowering:: +LowerGlobalAddress(SDValue Op, SelectionDAG &DAG) { + // FIXME there isn't actually debug info here + DebugLoc dl = Op.getDebugLoc(); + GlobalValue *GV = cast<GlobalAddressSDNode>(Op)->getGlobal(); + SDValue GA = DAG.getTargetGlobalAddress(GV, MVT::i32); + + return DAG.getNode(MBlazeISD::Wrap, dl, MVT::i32, GA); +} + +SDValue MBlazeTargetLowering:: +LowerGlobalTLSAddress(SDValue Op, SelectionDAG &DAG) { + llvm_unreachable("TLS not implemented for MicroBlaze."); + return SDValue(); // Not reached +} + +SDValue MBlazeTargetLowering:: +LowerJumpTable(SDValue Op, SelectionDAG &DAG) { + SDValue ResNode; + SDValue HiPart; + // FIXME there isn't actually debug info here + DebugLoc dl = Op.getDebugLoc(); + bool IsPIC = getTargetMachine().getRelocationModel() == Reloc::PIC_; + unsigned char OpFlag = IsPIC ? MBlazeII::MO_GOT : MBlazeII::MO_ABS_HILO; + + EVT PtrVT = Op.getValueType(); + JumpTableSDNode *JT = cast<JumpTableSDNode>(Op); + + SDValue JTI = DAG.getTargetJumpTable(JT->getIndex(), PtrVT, OpFlag); + return DAG.getNode(MBlazeISD::Wrap, dl, MVT::i32, JTI); + //return JTI; +} + +SDValue MBlazeTargetLowering:: +LowerConstantPool(SDValue Op, SelectionDAG &DAG) { + SDValue ResNode; + EVT PtrVT = Op.getValueType(); + ConstantPoolSDNode *N = cast<ConstantPoolSDNode>(Op); + Constant *C = N->getConstVal(); + SDValue Zero = DAG.getConstant(0, PtrVT); + DebugLoc dl = Op.getDebugLoc(); + + SDValue CP = DAG.getTargetConstantPool(C, MVT::i32, N->getAlignment(), + N->getOffset(), MBlazeII::MO_ABS_HILO); + return DAG.getNode(MBlazeISD::Wrap, dl, MVT::i32, CP); +} + +SDValue MBlazeTargetLowering::LowerVASTART(SDValue Op, SelectionDAG &DAG) { + DebugLoc dl = Op.getDebugLoc(); + SDValue FI = DAG.getFrameIndex(VarArgsFrameIndex, getPointerTy()); + + // vastart just stores the address of the VarArgsFrameIndex slot into the + // memory location argument. + const Value *SV = cast<SrcValueSDNode>(Op.getOperand(2))->getValue(); + return DAG.getStore(Op.getOperand(0), dl, FI, Op.getOperand(1), SV, 0, + false, false, 0); +} + +//===----------------------------------------------------------------------===// +// Calling Convention Implementation +//===----------------------------------------------------------------------===// + +#include "MBlazeGenCallingConv.inc" + +static bool CC_MBlaze2(unsigned ValNo, EVT ValVT, + EVT LocVT, CCValAssign::LocInfo LocInfo, + ISD::ArgFlagsTy ArgFlags, CCState &State) { + static const unsigned RegsSize=6; + static const unsigned IntRegs[] = { + MBlaze::R5, MBlaze::R6, MBlaze::R7, + MBlaze::R8, MBlaze::R9, MBlaze::R10 + }; + + static const unsigned FltRegs[] = { + MBlaze::F5, MBlaze::F6, MBlaze::F7, + MBlaze::F8, MBlaze::F9, MBlaze::F10 + }; + + unsigned Reg=0; + + // Promote i8 and i16 + if (LocVT == MVT::i8 || LocVT == MVT::i16) { + LocVT = MVT::i32; + if (ArgFlags.isSExt()) + LocInfo = CCValAssign::SExt; + else if (ArgFlags.isZExt()) + LocInfo = CCValAssign::ZExt; + else + LocInfo = CCValAssign::AExt; + } + + if (ValVT == MVT::i32) { + Reg = State.AllocateReg(IntRegs, RegsSize); + LocVT = MVT::i32; + } else if (ValVT == MVT::f32) { + Reg = State.AllocateReg(FltRegs, RegsSize); + LocVT = MVT::f32; + } + + if (!Reg) { + unsigned SizeInBytes = ValVT.getSizeInBits() >> 3; + unsigned Offset = State.AllocateStack(SizeInBytes, SizeInBytes); + State.addLoc(CCValAssign::getMem(ValNo, ValVT, Offset, LocVT, LocInfo)); + } else { + unsigned SizeInBytes = ValVT.getSizeInBits() >> 3; + State.AllocateStack(SizeInBytes, SizeInBytes); + State.addLoc(CCValAssign::getReg(ValNo, ValVT, Reg, LocVT, LocInfo)); + } + + return false; // CC must always match +} + +//===----------------------------------------------------------------------===// +// Call Calling Convention Implementation +//===----------------------------------------------------------------------===// + +/// LowerCall - functions arguments are copied from virtual regs to +/// (physical regs)/(stack frame), CALLSEQ_START and CALLSEQ_END are emitted. +/// TODO: isVarArg, isTailCall. +SDValue MBlazeTargetLowering:: +LowerCall(SDValue Chain, SDValue Callee, CallingConv::ID CallConv, + bool isVarArg, bool &isTailCall, + const SmallVectorImpl<ISD::OutputArg> &Outs, + const SmallVectorImpl<ISD::InputArg> &Ins, + DebugLoc dl, SelectionDAG &DAG, + SmallVectorImpl<SDValue> &InVals) { + // MBlaze does not yet support tail call optimization + isTailCall = false; + + MachineFunction &MF = DAG.getMachineFunction(); + MachineFrameInfo *MFI = MF.getFrameInfo(); + + // Analyze operands of the call, assigning locations to each operand. + SmallVector<CCValAssign, 16> ArgLocs; + CCState CCInfo(CallConv, isVarArg, getTargetMachine(), ArgLocs, + *DAG.getContext()); + CCInfo.AnalyzeCallOperands(Outs, CC_MBlaze2); + + // Get a count of how many bytes are to be pushed on the stack. + unsigned NumBytes = CCInfo.getNextStackOffset(); + Chain = DAG.getCALLSEQ_START(Chain, DAG.getIntPtrConstant(NumBytes, true)); + + SmallVector<std::pair<unsigned, SDValue>, 8> RegsToPass; + SmallVector<SDValue, 8> MemOpChains; + + // First/LastArgStackLoc contains the first/last + // "at stack" argument location. + int LastArgStackLoc = 0; + unsigned FirstStackArgLoc = 0; + + // Walk the register/memloc assignments, inserting copies/loads. + for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) { + CCValAssign &VA = ArgLocs[i]; + EVT RegVT = VA.getLocVT(); + SDValue Arg = Outs[i].Val; + + // Promote the value if needed. + switch (VA.getLocInfo()) { + default: llvm_unreachable("Unknown loc info!"); + case CCValAssign::Full: break; + case CCValAssign::SExt: + Arg = DAG.getNode(ISD::SIGN_EXTEND, dl, RegVT, Arg); + break; + case CCValAssign::ZExt: + Arg = DAG.getNode(ISD::ZERO_EXTEND, dl, RegVT, Arg); + break; + case CCValAssign::AExt: + Arg = DAG.getNode(ISD::ANY_EXTEND, dl, RegVT, Arg); + break; + } + + // Arguments that can be passed on register must be kept at + // RegsToPass vector + if (VA.isRegLoc()) { + RegsToPass.push_back(std::make_pair(VA.getLocReg(), Arg)); + } else { + // Register can't get to this point... + assert(VA.isMemLoc()); + + // Create the frame index object for this incoming parameter + LastArgStackLoc = (FirstStackArgLoc + VA.getLocMemOffset()); + int FI = MFI->CreateFixedObject(VA.getValVT().getSizeInBits()/8, + LastArgStackLoc, true, false); + + SDValue PtrOff = DAG.getFrameIndex(FI,getPointerTy()); + + // emit ISD::STORE whichs stores the + // parameter value to a stack Location + MemOpChains.push_back(DAG.getStore(Chain, dl, Arg, PtrOff, NULL, 0, + false, false, 0)); + } + } + + // Transform all store nodes into one single node because all store + // nodes are independent of each other. + if (!MemOpChains.empty()) + Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, + &MemOpChains[0], MemOpChains.size()); + + // Build a sequence of copy-to-reg nodes chained together with token + // chain and flag operands which copy the outgoing args into registers. + // The InFlag in necessary since all emited instructions must be + // stuck together. + SDValue InFlag; + for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i) { + Chain = DAG.getCopyToReg(Chain, dl, RegsToPass[i].first, + RegsToPass[i].second, InFlag); + InFlag = Chain.getValue(1); + } + + // If the callee is a GlobalAddress/ExternalSymbol node (quite common, every + // direct call is) turn it into a TargetGlobalAddress/TargetExternalSymbol + // node so that legalize doesn't hack it. + unsigned char OpFlag = MBlazeII::MO_NO_FLAG; + if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee)) + Callee = DAG.getTargetGlobalAddress(G->getGlobal(), + getPointerTy(), 0, OpFlag); + else if (ExternalSymbolSDNode *S = dyn_cast<ExternalSymbolSDNode>(Callee)) + Callee = DAG.getTargetExternalSymbol(S->getSymbol(), + getPointerTy(), OpFlag); + + // MBlazeJmpLink = #chain, #target_address, #opt_in_flags... + // = Chain, Callee, Reg#1, Reg#2, ... + // + // Returns a chain & a flag for retval copy to use. + SDVTList NodeTys = DAG.getVTList(MVT::Other, MVT::Flag); + SmallVector<SDValue, 8> Ops; + Ops.push_back(Chain); + Ops.push_back(Callee); + + // Add argument registers to the end of the list so that they are + // known live into the call. + for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i) { + Ops.push_back(DAG.getRegister(RegsToPass[i].first, + RegsToPass[i].second.getValueType())); + } + + if (InFlag.getNode()) + Ops.push_back(InFlag); + + Chain = DAG.getNode(MBlazeISD::JmpLink, dl, NodeTys, &Ops[0], Ops.size()); + InFlag = Chain.getValue(1); + + // Create the CALLSEQ_END node. + Chain = DAG.getCALLSEQ_END(Chain, DAG.getIntPtrConstant(NumBytes, true), + DAG.getIntPtrConstant(0, true), InFlag); + if (!Ins.empty()) + InFlag = Chain.getValue(1); + + // Handle result values, copying them out of physregs into vregs that we + // return. + return LowerCallResult(Chain, InFlag, CallConv, isVarArg, + Ins, dl, DAG, InVals); +} + +/// LowerCallResult - Lower the result values of a call into the +/// appropriate copies out of appropriate physical registers. +SDValue MBlazeTargetLowering:: +LowerCallResult(SDValue Chain, SDValue InFlag, CallingConv::ID CallConv, + bool isVarArg, const SmallVectorImpl<ISD::InputArg> &Ins, + DebugLoc dl, SelectionDAG &DAG, + SmallVectorImpl<SDValue> &InVals) { + // Assign locations to each value returned by this call. + SmallVector<CCValAssign, 16> RVLocs; + CCState CCInfo(CallConv, isVarArg, getTargetMachine(), + RVLocs, *DAG.getContext()); + + CCInfo.AnalyzeCallResult(Ins, RetCC_MBlaze); + + // Copy all of the result registers out of their specified physreg. + for (unsigned i = 0; i != RVLocs.size(); ++i) { + Chain = DAG.getCopyFromReg(Chain, dl, RVLocs[i].getLocReg(), + RVLocs[i].getValVT(), InFlag).getValue(1); + InFlag = Chain.getValue(2); + InVals.push_back(Chain.getValue(0)); + } + + return Chain; +} + +//===----------------------------------------------------------------------===// +// Formal Arguments Calling Convention Implementation +//===----------------------------------------------------------------------===// + +/// LowerFormalArguments - transform physical registers into +/// virtual registers and generate load operations for +/// arguments places on the stack. +SDValue MBlazeTargetLowering:: +LowerFormalArguments(SDValue Chain, CallingConv::ID CallConv, bool isVarArg, + const SmallVectorImpl<ISD::InputArg> &Ins, + DebugLoc dl, SelectionDAG &DAG, + SmallVectorImpl<SDValue> &InVals) { + MachineFunction &MF = DAG.getMachineFunction(); + MachineFrameInfo *MFI = MF.getFrameInfo(); + MBlazeFunctionInfo *MBlazeFI = MF.getInfo<MBlazeFunctionInfo>(); + + unsigned StackReg = MF.getTarget().getRegisterInfo()->getFrameRegister(MF); + VarArgsFrameIndex = 0; + + // Used with vargs to acumulate store chains. + std::vector<SDValue> OutChains; + + // Keep track of the last register used for arguments + unsigned ArgRegEnd = 0; + + // Assign locations to all of the incoming arguments. + SmallVector<CCValAssign, 16> ArgLocs; + CCState CCInfo(CallConv, isVarArg, getTargetMachine(), + ArgLocs, *DAG.getContext()); + + CCInfo.AnalyzeFormalArguments(Ins, CC_MBlaze2); + SDValue StackPtr; + + unsigned FirstStackArgLoc = 0; + + for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) { + CCValAssign &VA = ArgLocs[i]; + + // Arguments stored on registers + if (VA.isRegLoc()) { + EVT RegVT = VA.getLocVT(); + ArgRegEnd = VA.getLocReg(); + TargetRegisterClass *RC = 0; + + if (RegVT == MVT::i32) + RC = MBlaze::CPURegsRegisterClass; + else if (RegVT == MVT::f32) + RC = MBlaze::FGR32RegisterClass; + else + llvm_unreachable("RegVT not supported by LowerFormalArguments"); + + // Transform the arguments stored on + // physical registers into virtual ones + unsigned Reg = MF.addLiveIn(ArgRegEnd, RC); + SDValue ArgValue = DAG.getCopyFromReg(Chain, dl, Reg, RegVT); + + // If this is an 8 or 16-bit value, it has been passed promoted + // to 32 bits. Insert an assert[sz]ext to capture this, then + // truncate to the right size. If if is a floating point value + // then convert to the correct type. + if (VA.getLocInfo() != CCValAssign::Full) { + unsigned Opcode = 0; + if (VA.getLocInfo() == CCValAssign::SExt) + Opcode = ISD::AssertSext; + else if (VA.getLocInfo() == CCValAssign::ZExt) + Opcode = ISD::AssertZext; + if (Opcode) + ArgValue = DAG.getNode(Opcode, dl, RegVT, ArgValue, + DAG.getValueType(VA.getValVT())); + ArgValue = DAG.getNode(ISD::TRUNCATE, dl, VA.getValVT(), ArgValue); + } + + InVals.push_back(ArgValue); + + } else { // VA.isRegLoc() + + // sanity check + assert(VA.isMemLoc()); + + // The last argument is not a register + ArgRegEnd = 0; + + // The stack pointer offset is relative to the caller stack frame. + // Since the real stack size is unknown here, a negative SPOffset + // is used so there's a way to adjust these offsets when the stack + // size get known (on EliminateFrameIndex). A dummy SPOffset is + // used instead of a direct negative address (which is recorded to + // be used on emitPrologue) to avoid mis-calc of the first stack + // offset on PEI::calculateFrameObjectOffsets. + // Arguments are always 32-bit. + unsigned ArgSize = VA.getLocVT().getSizeInBits()/8; + int FI = MFI->CreateFixedObject(ArgSize, 0, true, false); + MBlazeFI->recordLoadArgsFI(FI, -(ArgSize+ + (FirstStackArgLoc + VA.getLocMemOffset()))); + + // Create load nodes to retrieve arguments from the stack + SDValue FIN = DAG.getFrameIndex(FI, getPointerTy()); + InVals.push_back(DAG.getLoad(VA.getValVT(), dl, Chain, FIN, NULL, 0, + false, false, 0)); + } + } + + // To meet ABI, when VARARGS are passed on registers, the registers + // must have their values written to the caller stack frame. If the last + // argument was placed in the stack, there's no need to save any register. + if ((isVarArg) && ArgRegEnd) { + if (StackPtr.getNode() == 0) + StackPtr = DAG.getRegister(StackReg, getPointerTy()); + + // The last register argument that must be saved is MBlaze::R10 + TargetRegisterClass *RC = MBlaze::CPURegsRegisterClass; + + unsigned Begin = MBlazeRegisterInfo::getRegisterNumbering(MBlaze::R5); + unsigned Start = MBlazeRegisterInfo::getRegisterNumbering(ArgRegEnd+1); + unsigned End = MBlazeRegisterInfo::getRegisterNumbering(MBlaze::R10); + unsigned StackLoc = ArgLocs.size()-1 + (Start - Begin); + + for (; Start <= End; ++Start, ++StackLoc) { + unsigned Reg = MBlazeRegisterInfo::getRegisterFromNumbering(Start); + unsigned LiveReg = MF.addLiveIn(Reg, RC); + SDValue ArgValue = DAG.getCopyFromReg(Chain, dl, LiveReg, MVT::i32); + + int FI = MFI->CreateFixedObject(4, 0, true, false); + MBlazeFI->recordStoreVarArgsFI(FI, -(4+(StackLoc*4))); + SDValue PtrOff = DAG.getFrameIndex(FI, getPointerTy()); + OutChains.push_back(DAG.getStore(Chain, dl, ArgValue, PtrOff, NULL, 0, + false, false, 0)); + + // Record the frame index of the first variable argument + // which is a value necessary to VASTART. + if (!VarArgsFrameIndex) + VarArgsFrameIndex = FI; + } + } + + // All stores are grouped in one node to allow the matching between + // the size of Ins and InVals. This only happens when on varg functions + if (!OutChains.empty()) { + OutChains.push_back(Chain); + Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, + &OutChains[0], OutChains.size()); + } + + return Chain; +} + +//===----------------------------------------------------------------------===// +// Return Value Calling Convention Implementation +//===----------------------------------------------------------------------===// + +SDValue MBlazeTargetLowering:: +LowerReturn(SDValue Chain, CallingConv::ID CallConv, bool isVarArg, + const SmallVectorImpl<ISD::OutputArg> &Outs, + DebugLoc dl, SelectionDAG &DAG) { + // CCValAssign - represent the assignment of + // the return value to a location + SmallVector<CCValAssign, 16> RVLocs; + + // CCState - Info about the registers and stack slot. + CCState CCInfo(CallConv, isVarArg, getTargetMachine(), + RVLocs, *DAG.getContext()); + + // Analize return values. + CCInfo.AnalyzeReturn(Outs, RetCC_MBlaze); + + // If this is the first return lowered for this function, add + // the regs to the liveout set for the function. + if (DAG.getMachineFunction().getRegInfo().liveout_empty()) { + for (unsigned i = 0; i != RVLocs.size(); ++i) + if (RVLocs[i].isRegLoc()) + DAG.getMachineFunction().getRegInfo().addLiveOut(RVLocs[i].getLocReg()); + } + + SDValue Flag; + + // Copy the result values into the output registers. + for (unsigned i = 0; i != RVLocs.size(); ++i) { + CCValAssign &VA = RVLocs[i]; + assert(VA.isRegLoc() && "Can only return in registers!"); + + Chain = DAG.getCopyToReg(Chain, dl, VA.getLocReg(), + Outs[i].Val, Flag); + + // guarantee that all emitted copies are + // stuck together, avoiding something bad + Flag = Chain.getValue(1); + } + + // Return on MBlaze is always a "rtsd R15, 8" + if (Flag.getNode()) + return DAG.getNode(MBlazeISD::Ret, dl, MVT::Other, + Chain, DAG.getRegister(MBlaze::R15, MVT::i32), Flag); + else // Return Void + return DAG.getNode(MBlazeISD::Ret, dl, MVT::Other, + Chain, DAG.getRegister(MBlaze::R15, MVT::i32)); +} + +//===----------------------------------------------------------------------===// +// MBlaze Inline Assembly Support +//===----------------------------------------------------------------------===// + +/// getConstraintType - Given a constraint letter, return the type of +/// constraint it is for this target. +MBlazeTargetLowering::ConstraintType MBlazeTargetLowering:: +getConstraintType(const std::string &Constraint) const +{ + // MBlaze specific constrainy + // + // 'd' : An address register. Equivalent to r. + // 'y' : Equivalent to r; retained for + // backwards compatibility. + // 'f' : Floating Point registers. + if (Constraint.size() == 1) { + switch (Constraint[0]) { + default : break; + case 'd': + case 'y': + case 'f': + return C_RegisterClass; + break; + } + } + return TargetLowering::getConstraintType(Constraint); +} + +/// getRegClassForInlineAsmConstraint - Given a constraint letter (e.g. "r"), +/// return a list of registers that can be used to satisfy the constraint. +/// This should only be used for C_RegisterClass constraints. +std::pair<unsigned, const TargetRegisterClass*> MBlazeTargetLowering:: +getRegForInlineAsmConstraint(const std::string &Constraint, EVT VT) const { + if (Constraint.size() == 1) { + switch (Constraint[0]) { + case 'r': + return std::make_pair(0U, MBlaze::CPURegsRegisterClass); + case 'f': + if (VT == MVT::f32) + return std::make_pair(0U, MBlaze::FGR32RegisterClass); + } + } + return TargetLowering::getRegForInlineAsmConstraint(Constraint, VT); +} + +/// Given a register class constraint, like 'r', if this corresponds directly +/// to an LLVM register class, return a register of 0 and the register class +/// pointer. +std::vector<unsigned> MBlazeTargetLowering:: +getRegClassForInlineAsmConstraint(const std::string &Constraint, EVT VT) const { + if (Constraint.size() != 1) + return std::vector<unsigned>(); + + switch (Constraint[0]) { + default : break; + case 'r': + // GCC MBlaze Constraint Letters + case 'd': + case 'y': + return make_vector<unsigned>( + MBlaze::R3, MBlaze::R4, MBlaze::R5, MBlaze::R6, + MBlaze::R7, MBlaze::R9, MBlaze::R10, MBlaze::R11, + MBlaze::R12, MBlaze::R19, MBlaze::R20, MBlaze::R21, + MBlaze::R22, MBlaze::R23, MBlaze::R24, MBlaze::R25, + MBlaze::R26, MBlaze::R27, MBlaze::R28, MBlaze::R29, + MBlaze::R30, MBlaze::R31, 0); + + case 'f': + return make_vector<unsigned>( + MBlaze::F3, MBlaze::F4, MBlaze::F5, MBlaze::F6, + MBlaze::F7, MBlaze::F9, MBlaze::F10, MBlaze::F11, + MBlaze::F12, MBlaze::F19, MBlaze::F20, MBlaze::F21, + MBlaze::F22, MBlaze::F23, MBlaze::F24, MBlaze::F25, + MBlaze::F26, MBlaze::F27, MBlaze::F28, MBlaze::F29, + MBlaze::F30, MBlaze::F31, 0); + } + return std::vector<unsigned>(); +} + +bool MBlazeTargetLowering:: +isOffsetFoldingLegal(const GlobalAddressSDNode *GA) const { + // The MBlaze target isn't yet aware of offsets. + return false; +} + +bool MBlazeTargetLowering::isFPImmLegal(const APFloat &Imm, EVT VT) const { + return VT != MVT::f32; +} |