| //===-- PPC32ISelLowering.cpp - PPC32 DAG Lowering Implementation ---------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file was developed by Chris Lattner and is distributed under |
| // the University of Illinois Open Source License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements the PPC32ISelLowering class. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "PPC32ISelLowering.h" |
| #include "PPC32TargetMachine.h" |
| #include "llvm/CodeGen/MachineFrameInfo.h" |
| #include "llvm/CodeGen/MachineFunction.h" |
| #include "llvm/CodeGen/SelectionDAG.h" |
| #include "llvm/Function.h" |
| using namespace llvm; |
| |
| PPC32TargetLowering::PPC32TargetLowering(TargetMachine &TM) |
| : TargetLowering(TM) { |
| |
| // Fold away setcc operations if possible. |
| setSetCCIsExpensive(); |
| |
| // Set up the register classes. |
| addRegisterClass(MVT::i32, PPC32::GPRCRegisterClass); |
| addRegisterClass(MVT::f32, PPC32::FPRCRegisterClass); |
| addRegisterClass(MVT::f64, PPC32::FPRCRegisterClass); |
| |
| // PowerPC has no intrinsics for these particular operations |
| setOperationAction(ISD::MEMMOVE, MVT::Other, Expand); |
| setOperationAction(ISD::MEMSET, MVT::Other, Expand); |
| setOperationAction(ISD::MEMCPY, MVT::Other, Expand); |
| |
| // PowerPC has an i16 but no i8 (or i1) SEXTLOAD |
| setOperationAction(ISD::SEXTLOAD, MVT::i1, Expand); |
| setOperationAction(ISD::SEXTLOAD, MVT::i8, Expand); |
| |
| // PowerPC has no SREM/UREM instructions |
| setOperationAction(ISD::SREM, MVT::i32, Expand); |
| setOperationAction(ISD::UREM, MVT::i32, Expand); |
| |
| // We don't support sin/cos/sqrt/fmod |
| setOperationAction(ISD::FSIN , MVT::f64, Expand); |
| setOperationAction(ISD::FCOS , MVT::f64, Expand); |
| setOperationAction(ISD::SREM , MVT::f64, Expand); |
| setOperationAction(ISD::FSIN , MVT::f32, Expand); |
| setOperationAction(ISD::FCOS , MVT::f32, Expand); |
| setOperationAction(ISD::SREM , MVT::f32, Expand); |
| |
| // If we're enabling GP optimizations, use hardware square root |
| if (!TM.getSubtarget<PPCSubtarget>().isGigaProcessor()) { |
| setOperationAction(ISD::FSQRT, MVT::f64, Expand); |
| setOperationAction(ISD::FSQRT, MVT::f32, Expand); |
| } |
| |
| // PowerPC does not have CTPOP or CTTZ |
| setOperationAction(ISD::CTPOP, MVT::i32 , Expand); |
| setOperationAction(ISD::CTTZ , MVT::i32 , Expand); |
| |
| // PowerPC does not have Select |
| setOperationAction(ISD::SELECT, MVT::i32, Expand); |
| setOperationAction(ISD::SELECT, MVT::f32, Expand); |
| setOperationAction(ISD::SELECT, MVT::f64, Expand); |
| |
| // PowerPC does not have BRCOND* which requires SetCC |
| setOperationAction(ISD::BRCOND, MVT::Other, Expand); |
| setOperationAction(ISD::BRCONDTWOWAY, MVT::Other, Expand); |
| |
| // PowerPC does not have FP_TO_UINT |
| setOperationAction(ISD::FP_TO_UINT, MVT::i32, Expand); |
| |
| // PowerPC does not have [U|S]INT_TO_FP |
| setOperationAction(ISD::SINT_TO_FP, MVT::i32, Expand); |
| setOperationAction(ISD::UINT_TO_FP, MVT::i32, Expand); |
| |
| setSetCCResultContents(ZeroOrOneSetCCResult); |
| addLegalFPImmediate(+0.0); // Necessary for FSEL |
| addLegalFPImmediate(-0.0); // |
| |
| computeRegisterProperties(); |
| } |
| |
| std::vector<SDOperand> |
| PPC32TargetLowering::LowerArguments(Function &F, SelectionDAG &DAG) { |
| // |
| // add beautiful description of PPC stack frame format, or at least some docs |
| // |
| MachineFunction &MF = DAG.getMachineFunction(); |
| MachineFrameInfo *MFI = MF.getFrameInfo(); |
| MachineBasicBlock& BB = MF.front(); |
| std::vector<SDOperand> ArgValues; |
| |
| // Due to the rather complicated nature of the PowerPC ABI, rather than a |
| // fixed size array of physical args, for the sake of simplicity let the STL |
| // handle tracking them for us. |
| std::vector<unsigned> argVR, argPR, argOp; |
| unsigned ArgOffset = 24; |
| unsigned GPR_remaining = 8; |
| unsigned FPR_remaining = 13; |
| unsigned GPR_idx = 0, FPR_idx = 0; |
| static const unsigned GPR[] = { |
| PPC::R3, PPC::R4, PPC::R5, PPC::R6, |
| PPC::R7, PPC::R8, PPC::R9, PPC::R10, |
| }; |
| static const unsigned FPR[] = { |
| PPC::F1, PPC::F2, PPC::F3, PPC::F4, PPC::F5, PPC::F6, PPC::F7, |
| PPC::F8, PPC::F9, PPC::F10, PPC::F11, PPC::F12, PPC::F13 |
| }; |
| |
| // Add DAG nodes to load the arguments... On entry to a function on PPC, |
| // the arguments start at offset 24, although they are likely to be passed |
| // in registers. |
| for (Function::arg_iterator I = F.arg_begin(), E = F.arg_end(); I != E; ++I) { |
| SDOperand newroot, argt; |
| unsigned ObjSize; |
| bool needsLoad = false; |
| bool ArgLive = !I->use_empty(); |
| MVT::ValueType ObjectVT = getValueType(I->getType()); |
| |
| switch (ObjectVT) { |
| default: assert(0 && "Unhandled argument type!"); |
| case MVT::i1: |
| case MVT::i8: |
| case MVT::i16: |
| case MVT::i32: |
| ObjSize = 4; |
| if (!ArgLive) break; |
| if (GPR_remaining > 0) { |
| MF.addLiveIn(GPR[GPR_idx]); |
| argt = newroot = DAG.getCopyFromReg(DAG.getRoot(), |
| GPR[GPR_idx], MVT::i32); |
| if (ObjectVT != MVT::i32) |
| argt = DAG.getNode(ISD::TRUNCATE, ObjectVT, newroot); |
| } else { |
| needsLoad = true; |
| } |
| break; |
| case MVT::i64: ObjSize = 8; |
| if (!ArgLive) break; |
| if (GPR_remaining > 0) { |
| SDOperand argHi, argLo; |
| MF.addLiveIn(GPR[GPR_idx]); |
| argHi = DAG.getCopyFromReg(DAG.getRoot(), GPR[GPR_idx], MVT::i32); |
| // If we have two or more remaining argument registers, then both halves |
| // of the i64 can be sourced from there. Otherwise, the lower half will |
| // have to come off the stack. This can happen when an i64 is preceded |
| // by 28 bytes of arguments. |
| if (GPR_remaining > 1) { |
| MF.addLiveIn(GPR[GPR_idx+1]); |
| argLo = DAG.getCopyFromReg(argHi, GPR[GPR_idx+1], MVT::i32); |
| } else { |
| int FI = MFI->CreateFixedObject(4, ArgOffset+4); |
| SDOperand FIN = DAG.getFrameIndex(FI, MVT::i32); |
| argLo = DAG.getLoad(MVT::i32, DAG.getEntryNode(), FIN, |
| DAG.getSrcValue(NULL)); |
| } |
| // Build the outgoing arg thingy |
| argt = DAG.getNode(ISD::BUILD_PAIR, MVT::i64, argLo, argHi); |
| newroot = argLo; |
| } else { |
| needsLoad = true; |
| } |
| break; |
| case MVT::f32: |
| case MVT::f64: |
| ObjSize = (ObjectVT == MVT::f64) ? 8 : 4; |
| if (!ArgLive) break; |
| if (FPR_remaining > 0) { |
| MF.addLiveIn(FPR[FPR_idx]); |
| argt = newroot = DAG.getCopyFromReg(DAG.getRoot(), |
| FPR[FPR_idx], ObjectVT); |
| --FPR_remaining; |
| ++FPR_idx; |
| } else { |
| needsLoad = true; |
| } |
| break; |
| } |
| |
| // We need to load the argument to a virtual register if we determined above |
| // that we ran out of physical registers of the appropriate type |
| if (needsLoad) { |
| unsigned SubregOffset = 0; |
| if (ObjectVT == MVT::i8 || ObjectVT == MVT::i1) SubregOffset = 3; |
| if (ObjectVT == MVT::i16) SubregOffset = 2; |
| int FI = MFI->CreateFixedObject(ObjSize, ArgOffset); |
| SDOperand FIN = DAG.getFrameIndex(FI, MVT::i32); |
| FIN = DAG.getNode(ISD::ADD, MVT::i32, FIN, |
| DAG.getConstant(SubregOffset, MVT::i32)); |
| argt = newroot = DAG.getLoad(ObjectVT, DAG.getEntryNode(), FIN, |
| DAG.getSrcValue(NULL)); |
| } |
| |
| // Every 4 bytes of argument space consumes one of the GPRs available for |
| // argument passing. |
| if (GPR_remaining > 0) { |
| unsigned delta = (GPR_remaining > 1 && ObjSize == 8) ? 2 : 1; |
| GPR_remaining -= delta; |
| GPR_idx += delta; |
| } |
| ArgOffset += ObjSize; |
| if (newroot.Val) |
| DAG.setRoot(newroot.getValue(1)); |
| |
| ArgValues.push_back(argt); |
| } |
| |
| // If the function takes variable number of arguments, make a frame index for |
| // the start of the first vararg value... for expansion of llvm.va_start. |
| if (F.isVarArg()) { |
| VarArgsFrameIndex = MFI->CreateFixedObject(4, ArgOffset); |
| SDOperand FIN = DAG.getFrameIndex(VarArgsFrameIndex, MVT::i32); |
| // If this function is vararg, store any remaining integer argument regs |
| // to their spots on the stack so that they may be loaded by deferencing the |
| // result of va_next. |
| std::vector<SDOperand> MemOps; |
| for (; GPR_remaining > 0; --GPR_remaining, ++GPR_idx) { |
| MF.addLiveIn(GPR[GPR_idx]); |
| SDOperand Val = DAG.getCopyFromReg(DAG.getRoot(), GPR[GPR_idx], MVT::i32); |
| SDOperand Store = DAG.getNode(ISD::STORE, MVT::Other, Val.getValue(1), |
| Val, FIN, DAG.getSrcValue(NULL)); |
| MemOps.push_back(Store); |
| // Increment the address by four for the next argument to store |
| SDOperand PtrOff = DAG.getConstant(4, getPointerTy()); |
| FIN = DAG.getNode(ISD::ADD, MVT::i32, FIN, PtrOff); |
| } |
| DAG.setRoot(DAG.getNode(ISD::TokenFactor, MVT::Other, MemOps)); |
| } |
| |
| // Finally, inform the code generator which regs we return values in. |
| switch (getValueType(F.getReturnType())) { |
| default: assert(0 && "Unknown type!"); |
| case MVT::isVoid: break; |
| case MVT::i1: |
| case MVT::i8: |
| case MVT::i16: |
| case MVT::i32: |
| MF.addLiveOut(PPC::R3); |
| break; |
| case MVT::i64: |
| MF.addLiveOut(PPC::R3); |
| MF.addLiveOut(PPC::R4); |
| break; |
| case MVT::f32: |
| case MVT::f64: |
| MF.addLiveOut(PPC::F1); |
| break; |
| } |
| |
| return ArgValues; |
| } |
| |
| std::pair<SDOperand, SDOperand> |
| PPC32TargetLowering::LowerCallTo(SDOperand Chain, |
| const Type *RetTy, bool isVarArg, |
| unsigned CallingConv, bool isTailCall, |
| SDOperand Callee, ArgListTy &Args, |
| SelectionDAG &DAG) { |
| // args_to_use will accumulate outgoing args for the ISD::CALL case in |
| // SelectExpr to use to put the arguments in the appropriate registers. |
| std::vector<SDOperand> args_to_use; |
| |
| // Count how many bytes are to be pushed on the stack, including the linkage |
| // area, and parameter passing area. |
| unsigned NumBytes = 24; |
| |
| if (Args.empty()) { |
| Chain = DAG.getNode(ISD::CALLSEQ_START, MVT::Other, Chain, |
| DAG.getConstant(NumBytes, getPointerTy())); |
| } else { |
| for (unsigned i = 0, e = Args.size(); i != e; ++i) |
| switch (getValueType(Args[i].second)) { |
| default: assert(0 && "Unknown value type!"); |
| case MVT::i1: |
| case MVT::i8: |
| case MVT::i16: |
| case MVT::i32: |
| case MVT::f32: |
| NumBytes += 4; |
| break; |
| case MVT::i64: |
| case MVT::f64: |
| NumBytes += 8; |
| break; |
| } |
| |
| // Just to be safe, we'll always reserve the full 24 bytes of linkage area |
| // plus 32 bytes of argument space in case any called code gets funky on us. |
| // (Required by ABI to support var arg) |
| if (NumBytes < 56) NumBytes = 56; |
| |
| // Adjust the stack pointer for the new arguments... |
| // These operations are automatically eliminated by the prolog/epilog pass |
| Chain = DAG.getNode(ISD::CALLSEQ_START, MVT::Other, Chain, |
| DAG.getConstant(NumBytes, getPointerTy())); |
| |
| // Set up a copy of the stack pointer for use loading and storing any |
| // arguments that may not fit in the registers available for argument |
| // passing. |
| SDOperand StackPtr = DAG.getCopyFromReg(DAG.getEntryNode(), |
| PPC::R1, MVT::i32); |
| |
| // Figure out which arguments are going to go in registers, and which in |
| // memory. Also, if this is a vararg function, floating point operations |
| // must be stored to our stack, and loaded into integer regs as well, if |
| // any integer regs are available for argument passing. |
| unsigned ArgOffset = 24; |
| unsigned GPR_remaining = 8; |
| unsigned FPR_remaining = 13; |
| |
| std::vector<SDOperand> MemOps; |
| for (unsigned i = 0, e = Args.size(); i != e; ++i) { |
| // PtrOff will be used to store the current argument to the stack if a |
| // register cannot be found for it. |
| SDOperand PtrOff = DAG.getConstant(ArgOffset, getPointerTy()); |
| PtrOff = DAG.getNode(ISD::ADD, MVT::i32, StackPtr, PtrOff); |
| MVT::ValueType ArgVT = getValueType(Args[i].second); |
| |
| switch (ArgVT) { |
| default: assert(0 && "Unexpected ValueType for argument!"); |
| case MVT::i1: |
| case MVT::i8: |
| case MVT::i16: |
| // Promote the integer to 32 bits. If the input type is signed use a |
| // sign extend, otherwise use a zero extend. |
| if (Args[i].second->isSigned()) |
| Args[i].first =DAG.getNode(ISD::SIGN_EXTEND, MVT::i32, Args[i].first); |
| else |
| Args[i].first =DAG.getNode(ISD::ZERO_EXTEND, MVT::i32, Args[i].first); |
| // FALL THROUGH |
| case MVT::i32: |
| if (GPR_remaining > 0) { |
| args_to_use.push_back(Args[i].first); |
| --GPR_remaining; |
| } else { |
| MemOps.push_back(DAG.getNode(ISD::STORE, MVT::Other, Chain, |
| Args[i].first, PtrOff, |
| DAG.getSrcValue(NULL))); |
| } |
| ArgOffset += 4; |
| break; |
| case MVT::i64: |
| // If we have one free GPR left, we can place the upper half of the i64 |
| // in it, and store the other half to the stack. If we have two or more |
| // free GPRs, then we can pass both halves of the i64 in registers. |
| if (GPR_remaining > 0) { |
| SDOperand Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, MVT::i32, |
| Args[i].first, DAG.getConstant(1, MVT::i32)); |
| SDOperand Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, MVT::i32, |
| Args[i].first, DAG.getConstant(0, MVT::i32)); |
| args_to_use.push_back(Hi); |
| --GPR_remaining; |
| if (GPR_remaining > 0) { |
| args_to_use.push_back(Lo); |
| --GPR_remaining; |
| } else { |
| SDOperand ConstFour = DAG.getConstant(4, getPointerTy()); |
| PtrOff = DAG.getNode(ISD::ADD, MVT::i32, PtrOff, ConstFour); |
| MemOps.push_back(DAG.getNode(ISD::STORE, MVT::Other, Chain, |
| Lo, PtrOff, DAG.getSrcValue(NULL))); |
| } |
| } else { |
| MemOps.push_back(DAG.getNode(ISD::STORE, MVT::Other, Chain, |
| Args[i].first, PtrOff, |
| DAG.getSrcValue(NULL))); |
| } |
| ArgOffset += 8; |
| break; |
| case MVT::f32: |
| case MVT::f64: |
| if (FPR_remaining > 0) { |
| args_to_use.push_back(Args[i].first); |
| --FPR_remaining; |
| if (isVarArg) { |
| SDOperand Store = DAG.getNode(ISD::STORE, MVT::Other, Chain, |
| Args[i].first, PtrOff, |
| DAG.getSrcValue(NULL)); |
| MemOps.push_back(Store); |
| // Float varargs are always shadowed in available integer registers |
| if (GPR_remaining > 0) { |
| SDOperand Load = DAG.getLoad(MVT::i32, Store, PtrOff, |
| DAG.getSrcValue(NULL)); |
| MemOps.push_back(Load); |
| args_to_use.push_back(Load); |
| --GPR_remaining; |
| } |
| if (GPR_remaining > 0 && MVT::f64 == ArgVT) { |
| SDOperand ConstFour = DAG.getConstant(4, getPointerTy()); |
| PtrOff = DAG.getNode(ISD::ADD, MVT::i32, PtrOff, ConstFour); |
| SDOperand Load = DAG.getLoad(MVT::i32, Store, PtrOff, |
| DAG.getSrcValue(NULL)); |
| MemOps.push_back(Load); |
| args_to_use.push_back(Load); |
| --GPR_remaining; |
| } |
| } else { |
| // If we have any FPRs remaining, we may also have GPRs remaining. |
| // Args passed in FPRs consume either 1 (f32) or 2 (f64) available |
| // GPRs. |
| if (GPR_remaining > 0) { |
| args_to_use.push_back(DAG.getNode(ISD::UNDEF, MVT::i32)); |
| --GPR_remaining; |
| } |
| if (GPR_remaining > 0 && MVT::f64 == ArgVT) { |
| args_to_use.push_back(DAG.getNode(ISD::UNDEF, MVT::i32)); |
| --GPR_remaining; |
| } |
| } |
| } else { |
| MemOps.push_back(DAG.getNode(ISD::STORE, MVT::Other, Chain, |
| Args[i].first, PtrOff, |
| DAG.getSrcValue(NULL))); |
| } |
| ArgOffset += (ArgVT == MVT::f32) ? 4 : 8; |
| break; |
| } |
| } |
| if (!MemOps.empty()) |
| Chain = DAG.getNode(ISD::TokenFactor, MVT::Other, MemOps); |
| } |
| |
| std::vector<MVT::ValueType> RetVals; |
| MVT::ValueType RetTyVT = getValueType(RetTy); |
| if (RetTyVT != MVT::isVoid) |
| RetVals.push_back(RetTyVT); |
| RetVals.push_back(MVT::Other); |
| |
| SDOperand TheCall = SDOperand(DAG.getCall(RetVals, |
| Chain, Callee, args_to_use), 0); |
| Chain = TheCall.getValue(RetTyVT != MVT::isVoid); |
| Chain = DAG.getNode(ISD::CALLSEQ_END, MVT::Other, Chain, |
| DAG.getConstant(NumBytes, getPointerTy())); |
| return std::make_pair(TheCall, Chain); |
| } |
| |
| SDOperand PPC32TargetLowering::LowerVAStart(SDOperand Chain, SDOperand VAListP, |
| Value *VAListV, SelectionDAG &DAG) { |
| // vastart just stores the address of the VarArgsFrameIndex slot into the |
| // memory location argument. |
| SDOperand FR = DAG.getFrameIndex(VarArgsFrameIndex, MVT::i32); |
| return DAG.getNode(ISD::STORE, MVT::Other, Chain, FR, VAListP, |
| DAG.getSrcValue(VAListV)); |
| } |
| |
| std::pair<SDOperand,SDOperand> |
| PPC32TargetLowering::LowerVAArg(SDOperand Chain, |
| SDOperand VAListP, Value *VAListV, |
| const Type *ArgTy, SelectionDAG &DAG) { |
| MVT::ValueType ArgVT = getValueType(ArgTy); |
| |
| SDOperand VAList = |
| DAG.getLoad(MVT::i32, Chain, VAListP, DAG.getSrcValue(VAListV)); |
| SDOperand Result = DAG.getLoad(ArgVT, Chain, VAList, DAG.getSrcValue(NULL)); |
| unsigned Amt; |
| if (ArgVT == MVT::i32 || ArgVT == MVT::f32) |
| Amt = 4; |
| else { |
| assert((ArgVT == MVT::i64 || ArgVT == MVT::f64) && |
| "Other types should have been promoted for varargs!"); |
| Amt = 8; |
| } |
| VAList = DAG.getNode(ISD::ADD, VAList.getValueType(), VAList, |
| DAG.getConstant(Amt, VAList.getValueType())); |
| Chain = DAG.getNode(ISD::STORE, MVT::Other, Chain, |
| VAList, VAListP, DAG.getSrcValue(VAListV)); |
| return std::make_pair(Result, Chain); |
| } |
| |
| |
| std::pair<SDOperand, SDOperand> PPC32TargetLowering:: |
| LowerFrameReturnAddress(bool isFrameAddress, SDOperand Chain, unsigned Depth, |
| SelectionDAG &DAG) { |
| assert(0 && "LowerFrameReturnAddress unimplemented"); |
| abort(); |
| } |