1 //===-- MSP430ISelLowering.cpp - MSP430 DAG Lowering Implementation ------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements the MSP430TargetLowering class.
12 //===----------------------------------------------------------------------===//
14 #define DEBUG_TYPE "msp430-lower"
16 #include "MSP430ISelLowering.h"
18 #include "MSP430MachineFunctionInfo.h"
19 #include "MSP430TargetMachine.h"
20 #include "MSP430Subtarget.h"
21 #include "llvm/DerivedTypes.h"
22 #include "llvm/Function.h"
23 #include "llvm/Intrinsics.h"
24 #include "llvm/CallingConv.h"
25 #include "llvm/GlobalVariable.h"
26 #include "llvm/GlobalAlias.h"
27 #include "llvm/CodeGen/CallingConvLower.h"
28 #include "llvm/CodeGen/MachineFrameInfo.h"
29 #include "llvm/CodeGen/MachineFunction.h"
30 #include "llvm/CodeGen/MachineInstrBuilder.h"
31 #include "llvm/CodeGen/MachineRegisterInfo.h"
32 #include "llvm/CodeGen/PseudoSourceValue.h"
33 #include "llvm/CodeGen/SelectionDAGISel.h"
34 #include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
35 #include "llvm/CodeGen/ValueTypes.h"
36 #include "llvm/Support/CommandLine.h"
37 #include "llvm/Support/Debug.h"
38 #include "llvm/Support/ErrorHandling.h"
39 #include "llvm/Support/raw_ostream.h"
40 #include "llvm/ADT/VectorExtras.h"
49 static cl::opt<HWMultUseMode>
50 HWMultMode("msp430-hwmult-mode",
51 cl::desc("Hardware multiplier use mode"),
52 cl::init(HWMultNoIntr),
54 clEnumValN(NoHWMult, "no",
55 "Do not use hardware multiplier"),
56 clEnumValN(HWMultIntr, "interrupts",
57 "Assume hardware multiplier can be used inside interrupts"),
58 clEnumValN(HWMultNoIntr, "use",
59 "Assume hardware multiplier cannot be used inside interrupts"),
62 MSP430TargetLowering::MSP430TargetLowering(MSP430TargetMachine &tm) :
63 TargetLowering(tm, new TargetLoweringObjectFileELF()),
64 Subtarget(*tm.getSubtargetImpl()), TM(tm) {
68 // Set up the register classes.
69 addRegisterClass(MVT::i8, MSP430::GR8RegisterClass);
70 addRegisterClass(MVT::i16, MSP430::GR16RegisterClass);
72 // Compute derived properties from the register classes
73 computeRegisterProperties();
75 // Provide all sorts of operation actions
77 // Division is expensive
78 setIntDivIsCheap(false);
80 setStackPointerRegisterToSaveRestore(MSP430::SPW);
81 setBooleanContents(ZeroOrOneBooleanContent);
82 setBooleanVectorContents(ZeroOrOneBooleanContent); // FIXME: Is this correct?
83 setSchedulingPreference(Sched::Latency);
85 // We have post-incremented loads / stores.
86 setIndexedLoadAction(ISD::POST_INC, MVT::i8, Legal);
87 setIndexedLoadAction(ISD::POST_INC, MVT::i16, Legal);
89 setLoadExtAction(ISD::EXTLOAD, MVT::i1, Promote);
90 setLoadExtAction(ISD::SEXTLOAD, MVT::i1, Promote);
91 setLoadExtAction(ISD::ZEXTLOAD, MVT::i1, Promote);
92 setLoadExtAction(ISD::SEXTLOAD, MVT::i8, Expand);
93 setLoadExtAction(ISD::SEXTLOAD, MVT::i16, Expand);
95 // We don't have any truncstores
96 setTruncStoreAction(MVT::i16, MVT::i8, Expand);
98 setOperationAction(ISD::SRA, MVT::i8, Custom);
99 setOperationAction(ISD::SHL, MVT::i8, Custom);
100 setOperationAction(ISD::SRL, MVT::i8, Custom);
101 setOperationAction(ISD::SRA, MVT::i16, Custom);
102 setOperationAction(ISD::SHL, MVT::i16, Custom);
103 setOperationAction(ISD::SRL, MVT::i16, Custom);
104 setOperationAction(ISD::ROTL, MVT::i8, Expand);
105 setOperationAction(ISD::ROTR, MVT::i8, Expand);
106 setOperationAction(ISD::ROTL, MVT::i16, Expand);
107 setOperationAction(ISD::ROTR, MVT::i16, Expand);
108 setOperationAction(ISD::GlobalAddress, MVT::i16, Custom);
109 setOperationAction(ISD::ExternalSymbol, MVT::i16, Custom);
110 setOperationAction(ISD::BlockAddress, MVT::i16, Custom);
111 setOperationAction(ISD::BR_JT, MVT::Other, Expand);
112 setOperationAction(ISD::BR_CC, MVT::i8, Custom);
113 setOperationAction(ISD::BR_CC, MVT::i16, Custom);
114 setOperationAction(ISD::BRCOND, MVT::Other, Expand);
115 setOperationAction(ISD::SETCC, MVT::i8, Custom);
116 setOperationAction(ISD::SETCC, MVT::i16, Custom);
117 setOperationAction(ISD::SELECT, MVT::i8, Expand);
118 setOperationAction(ISD::SELECT, MVT::i16, Expand);
119 setOperationAction(ISD::SELECT_CC, MVT::i8, Custom);
120 setOperationAction(ISD::SELECT_CC, MVT::i16, Custom);
121 setOperationAction(ISD::SIGN_EXTEND, MVT::i16, Custom);
122 setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i8, Expand);
123 setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i16, Expand);
125 setOperationAction(ISD::CTTZ, MVT::i8, Expand);
126 setOperationAction(ISD::CTTZ, MVT::i16, Expand);
127 setOperationAction(ISD::CTLZ, MVT::i8, Expand);
128 setOperationAction(ISD::CTLZ, MVT::i16, Expand);
129 setOperationAction(ISD::CTPOP, MVT::i8, Expand);
130 setOperationAction(ISD::CTPOP, MVT::i16, Expand);
132 setOperationAction(ISD::SHL_PARTS, MVT::i8, Expand);
133 setOperationAction(ISD::SHL_PARTS, MVT::i16, Expand);
134 setOperationAction(ISD::SRL_PARTS, MVT::i8, Expand);
135 setOperationAction(ISD::SRL_PARTS, MVT::i16, Expand);
136 setOperationAction(ISD::SRA_PARTS, MVT::i8, Expand);
137 setOperationAction(ISD::SRA_PARTS, MVT::i16, Expand);
139 setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i1, Expand);
141 // FIXME: Implement efficiently multiplication by a constant
142 setOperationAction(ISD::MUL, MVT::i8, Expand);
143 setOperationAction(ISD::MULHS, MVT::i8, Expand);
144 setOperationAction(ISD::MULHU, MVT::i8, Expand);
145 setOperationAction(ISD::SMUL_LOHI, MVT::i8, Expand);
146 setOperationAction(ISD::UMUL_LOHI, MVT::i8, Expand);
147 setOperationAction(ISD::MUL, MVT::i16, Expand);
148 setOperationAction(ISD::MULHS, MVT::i16, Expand);
149 setOperationAction(ISD::MULHU, MVT::i16, Expand);
150 setOperationAction(ISD::SMUL_LOHI, MVT::i16, Expand);
151 setOperationAction(ISD::UMUL_LOHI, MVT::i16, Expand);
153 setOperationAction(ISD::UDIV, MVT::i8, Expand);
154 setOperationAction(ISD::UDIVREM, MVT::i8, Expand);
155 setOperationAction(ISD::UREM, MVT::i8, Expand);
156 setOperationAction(ISD::SDIV, MVT::i8, Expand);
157 setOperationAction(ISD::SDIVREM, MVT::i8, Expand);
158 setOperationAction(ISD::SREM, MVT::i8, Expand);
159 setOperationAction(ISD::UDIV, MVT::i16, Expand);
160 setOperationAction(ISD::UDIVREM, MVT::i16, Expand);
161 setOperationAction(ISD::UREM, MVT::i16, Expand);
162 setOperationAction(ISD::SDIV, MVT::i16, Expand);
163 setOperationAction(ISD::SDIVREM, MVT::i16, Expand);
164 setOperationAction(ISD::SREM, MVT::i16, Expand);
167 if (HWMultMode == HWMultIntr) {
168 setLibcallName(RTLIB::MUL_I8, "__mulqi3hw");
169 setLibcallName(RTLIB::MUL_I16, "__mulhi3hw");
170 } else if (HWMultMode == HWMultNoIntr) {
171 setLibcallName(RTLIB::MUL_I8, "__mulqi3hw_noint");
172 setLibcallName(RTLIB::MUL_I16, "__mulhi3hw_noint");
175 setMinFunctionAlignment(1);
176 setPrefFunctionAlignment(2);
179 SDValue MSP430TargetLowering::LowerOperation(SDValue Op,
180 SelectionDAG &DAG) const {
181 switch (Op.getOpcode()) {
182 case ISD::SHL: // FALLTHROUGH
184 case ISD::SRA: return LowerShifts(Op, DAG);
185 case ISD::GlobalAddress: return LowerGlobalAddress(Op, DAG);
186 case ISD::BlockAddress: return LowerBlockAddress(Op, DAG);
187 case ISD::ExternalSymbol: return LowerExternalSymbol(Op, DAG);
188 case ISD::SETCC: return LowerSETCC(Op, DAG);
189 case ISD::BR_CC: return LowerBR_CC(Op, DAG);
190 case ISD::SELECT_CC: return LowerSELECT_CC(Op, DAG);
191 case ISD::SIGN_EXTEND: return LowerSIGN_EXTEND(Op, DAG);
192 case ISD::RETURNADDR: return LowerRETURNADDR(Op, DAG);
193 case ISD::FRAMEADDR: return LowerFRAMEADDR(Op, DAG);
195 llvm_unreachable("unimplemented operand");
200 //===----------------------------------------------------------------------===//
201 // MSP430 Inline Assembly Support
202 //===----------------------------------------------------------------------===//
204 /// getConstraintType - Given a constraint letter, return the type of
205 /// constraint it is for this target.
206 TargetLowering::ConstraintType
207 MSP430TargetLowering::getConstraintType(const std::string &Constraint) const {
208 if (Constraint.size() == 1) {
209 switch (Constraint[0]) {
211 return C_RegisterClass;
216 return TargetLowering::getConstraintType(Constraint);
219 std::pair<unsigned, const TargetRegisterClass*>
220 MSP430TargetLowering::
221 getRegForInlineAsmConstraint(const std::string &Constraint,
223 if (Constraint.size() == 1) {
224 // GCC Constraint Letters
225 switch (Constraint[0]) {
227 case 'r': // GENERAL_REGS
229 return std::make_pair(0U, MSP430::GR8RegisterClass);
231 return std::make_pair(0U, MSP430::GR16RegisterClass);
235 return TargetLowering::getRegForInlineAsmConstraint(Constraint, VT);
238 //===----------------------------------------------------------------------===//
239 // Calling Convention Implementation
240 //===----------------------------------------------------------------------===//
242 #include "MSP430GenCallingConv.inc"
245 MSP430TargetLowering::LowerFormalArguments(SDValue Chain,
246 CallingConv::ID CallConv,
248 const SmallVectorImpl<ISD::InputArg>
252 SmallVectorImpl<SDValue> &InVals)
257 llvm_unreachable("Unsupported calling convention");
259 case CallingConv::Fast:
260 return LowerCCCArguments(Chain, CallConv, isVarArg, Ins, dl, DAG, InVals);
261 case CallingConv::MSP430_INTR:
265 report_fatal_error("ISRs cannot have arguments");
272 MSP430TargetLowering::LowerCall(SDValue Chain, SDValue Callee,
273 CallingConv::ID CallConv, bool isVarArg,
275 const SmallVectorImpl<ISD::OutputArg> &Outs,
276 const SmallVectorImpl<SDValue> &OutVals,
277 const SmallVectorImpl<ISD::InputArg> &Ins,
278 DebugLoc dl, SelectionDAG &DAG,
279 SmallVectorImpl<SDValue> &InVals) const {
280 // MSP430 target does not yet support tail call optimization.
285 llvm_unreachable("Unsupported calling convention");
286 case CallingConv::Fast:
288 return LowerCCCCallTo(Chain, Callee, CallConv, isVarArg, isTailCall,
289 Outs, OutVals, Ins, dl, DAG, InVals);
290 case CallingConv::MSP430_INTR:
291 report_fatal_error("ISRs cannot be called directly");
296 /// LowerCCCArguments - transform physical registers into virtual registers and
297 /// generate load operations for arguments places on the stack.
298 // FIXME: struct return stuff
301 MSP430TargetLowering::LowerCCCArguments(SDValue Chain,
302 CallingConv::ID CallConv,
304 const SmallVectorImpl<ISD::InputArg>
308 SmallVectorImpl<SDValue> &InVals)
310 MachineFunction &MF = DAG.getMachineFunction();
311 MachineFrameInfo *MFI = MF.getFrameInfo();
312 MachineRegisterInfo &RegInfo = MF.getRegInfo();
314 // Assign locations to all of the incoming arguments.
315 SmallVector<CCValAssign, 16> ArgLocs;
316 CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(),
317 getTargetMachine(), ArgLocs, *DAG.getContext());
318 CCInfo.AnalyzeFormalArguments(Ins, CC_MSP430);
320 assert(!isVarArg && "Varargs not supported yet");
322 for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
323 CCValAssign &VA = ArgLocs[i];
325 // Arguments passed in registers
326 EVT RegVT = VA.getLocVT();
327 switch (RegVT.getSimpleVT().SimpleTy) {
331 errs() << "LowerFormalArguments Unhandled argument type: "
332 << RegVT.getSimpleVT().SimpleTy << "\n";
338 RegInfo.createVirtualRegister(MSP430::GR16RegisterClass);
339 RegInfo.addLiveIn(VA.getLocReg(), VReg);
340 SDValue ArgValue = DAG.getCopyFromReg(Chain, dl, VReg, RegVT);
342 // If this is an 8-bit value, it is really passed promoted to 16
343 // bits. Insert an assert[sz]ext to capture this, then truncate to the
345 if (VA.getLocInfo() == CCValAssign::SExt)
346 ArgValue = DAG.getNode(ISD::AssertSext, dl, RegVT, ArgValue,
347 DAG.getValueType(VA.getValVT()));
348 else if (VA.getLocInfo() == CCValAssign::ZExt)
349 ArgValue = DAG.getNode(ISD::AssertZext, dl, RegVT, ArgValue,
350 DAG.getValueType(VA.getValVT()));
352 if (VA.getLocInfo() != CCValAssign::Full)
353 ArgValue = DAG.getNode(ISD::TRUNCATE, dl, VA.getValVT(), ArgValue);
355 InVals.push_back(ArgValue);
359 assert(VA.isMemLoc());
360 // Load the argument to a virtual register
361 unsigned ObjSize = VA.getLocVT().getSizeInBits()/8;
363 errs() << "LowerFormalArguments Unhandled argument type: "
364 << EVT(VA.getLocVT()).getEVTString()
367 // Create the frame index object for this incoming parameter...
368 int FI = MFI->CreateFixedObject(ObjSize, VA.getLocMemOffset(), true);
370 // Create the SelectionDAG nodes corresponding to a load
371 //from this parameter
372 SDValue FIN = DAG.getFrameIndex(FI, MVT::i16);
373 InVals.push_back(DAG.getLoad(VA.getLocVT(), dl, Chain, FIN,
374 MachinePointerInfo::getFixedStack(FI),
383 MSP430TargetLowering::LowerReturn(SDValue Chain,
384 CallingConv::ID CallConv, bool isVarArg,
385 const SmallVectorImpl<ISD::OutputArg> &Outs,
386 const SmallVectorImpl<SDValue> &OutVals,
387 DebugLoc dl, SelectionDAG &DAG) const {
389 // CCValAssign - represent the assignment of the return value to a location
390 SmallVector<CCValAssign, 16> RVLocs;
392 // ISRs cannot return any value.
393 if (CallConv == CallingConv::MSP430_INTR && !Outs.empty()) {
394 report_fatal_error("ISRs cannot return any value");
398 // CCState - Info about the registers and stack slot.
399 CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(),
400 getTargetMachine(), RVLocs, *DAG.getContext());
402 // Analize return values.
403 CCInfo.AnalyzeReturn(Outs, RetCC_MSP430);
405 // If this is the first return lowered for this function, add the regs to the
406 // liveout set for the function.
407 if (DAG.getMachineFunction().getRegInfo().liveout_empty()) {
408 for (unsigned i = 0; i != RVLocs.size(); ++i)
409 if (RVLocs[i].isRegLoc())
410 DAG.getMachineFunction().getRegInfo().addLiveOut(RVLocs[i].getLocReg());
415 // Copy the result values into the output registers.
416 for (unsigned i = 0; i != RVLocs.size(); ++i) {
417 CCValAssign &VA = RVLocs[i];
418 assert(VA.isRegLoc() && "Can only return in registers!");
420 Chain = DAG.getCopyToReg(Chain, dl, VA.getLocReg(),
423 // Guarantee that all emitted copies are stuck together,
424 // avoiding something bad.
425 Flag = Chain.getValue(1);
428 unsigned Opc = (CallConv == CallingConv::MSP430_INTR ?
429 MSP430ISD::RETI_FLAG : MSP430ISD::RET_FLAG);
432 return DAG.getNode(Opc, dl, MVT::Other, Chain, Flag);
435 return DAG.getNode(Opc, dl, MVT::Other, Chain);
438 /// LowerCCCCallTo - functions arguments are copied from virtual regs to
439 /// (physical regs)/(stack frame), CALLSEQ_START and CALLSEQ_END are emitted.
442 MSP430TargetLowering::LowerCCCCallTo(SDValue Chain, SDValue Callee,
443 CallingConv::ID CallConv, bool isVarArg,
445 const SmallVectorImpl<ISD::OutputArg>
447 const SmallVectorImpl<SDValue> &OutVals,
448 const SmallVectorImpl<ISD::InputArg> &Ins,
449 DebugLoc dl, SelectionDAG &DAG,
450 SmallVectorImpl<SDValue> &InVals) const {
451 // Analyze operands of the call, assigning locations to each operand.
452 SmallVector<CCValAssign, 16> ArgLocs;
453 CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(),
454 getTargetMachine(), ArgLocs, *DAG.getContext());
456 CCInfo.AnalyzeCallOperands(Outs, CC_MSP430);
458 // Get a count of how many bytes are to be pushed on the stack.
459 unsigned NumBytes = CCInfo.getNextStackOffset();
461 Chain = DAG.getCALLSEQ_START(Chain ,DAG.getConstant(NumBytes,
462 getPointerTy(), true));
464 SmallVector<std::pair<unsigned, SDValue>, 4> RegsToPass;
465 SmallVector<SDValue, 12> MemOpChains;
468 // Walk the register/memloc assignments, inserting copies/loads.
469 for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
470 CCValAssign &VA = ArgLocs[i];
472 SDValue Arg = OutVals[i];
474 // Promote the value if needed.
475 switch (VA.getLocInfo()) {
476 default: llvm_unreachable("Unknown loc info!");
477 case CCValAssign::Full: break;
478 case CCValAssign::SExt:
479 Arg = DAG.getNode(ISD::SIGN_EXTEND, dl, VA.getLocVT(), Arg);
481 case CCValAssign::ZExt:
482 Arg = DAG.getNode(ISD::ZERO_EXTEND, dl, VA.getLocVT(), Arg);
484 case CCValAssign::AExt:
485 Arg = DAG.getNode(ISD::ANY_EXTEND, dl, VA.getLocVT(), Arg);
489 // Arguments that can be passed on register must be kept at RegsToPass
492 RegsToPass.push_back(std::make_pair(VA.getLocReg(), Arg));
494 assert(VA.isMemLoc());
496 if (StackPtr.getNode() == 0)
497 StackPtr = DAG.getCopyFromReg(Chain, dl, MSP430::SPW, getPointerTy());
499 SDValue PtrOff = DAG.getNode(ISD::ADD, dl, getPointerTy(),
501 DAG.getIntPtrConstant(VA.getLocMemOffset()));
504 MemOpChains.push_back(DAG.getStore(Chain, dl, Arg, PtrOff,
505 MachinePointerInfo(),false, false, 0));
509 // Transform all store nodes into one single node because all store nodes are
510 // independent of each other.
511 if (!MemOpChains.empty())
512 Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
513 &MemOpChains[0], MemOpChains.size());
515 // Build a sequence of copy-to-reg nodes chained together with token chain and
516 // flag operands which copy the outgoing args into registers. The InFlag in
517 // necessary since all emitted instructions must be stuck together.
519 for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i) {
520 Chain = DAG.getCopyToReg(Chain, dl, RegsToPass[i].first,
521 RegsToPass[i].second, InFlag);
522 InFlag = Chain.getValue(1);
525 // If the callee is a GlobalAddress node (quite common, every direct call is)
526 // turn it into a TargetGlobalAddress node so that legalize doesn't hack it.
527 // Likewise ExternalSymbol -> TargetExternalSymbol.
528 if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee))
529 Callee = DAG.getTargetGlobalAddress(G->getGlobal(), dl, MVT::i16);
530 else if (ExternalSymbolSDNode *E = dyn_cast<ExternalSymbolSDNode>(Callee))
531 Callee = DAG.getTargetExternalSymbol(E->getSymbol(), MVT::i16);
533 // Returns a chain & a flag for retval copy to use.
534 SDVTList NodeTys = DAG.getVTList(MVT::Other, MVT::Glue);
535 SmallVector<SDValue, 8> Ops;
536 Ops.push_back(Chain);
537 Ops.push_back(Callee);
539 // Add argument registers to the end of the list so that they are
540 // known live into the call.
541 for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i)
542 Ops.push_back(DAG.getRegister(RegsToPass[i].first,
543 RegsToPass[i].second.getValueType()));
545 if (InFlag.getNode())
546 Ops.push_back(InFlag);
548 Chain = DAG.getNode(MSP430ISD::CALL, dl, NodeTys, &Ops[0], Ops.size());
549 InFlag = Chain.getValue(1);
551 // Create the CALLSEQ_END node.
552 Chain = DAG.getCALLSEQ_END(Chain,
553 DAG.getConstant(NumBytes, getPointerTy(), true),
554 DAG.getConstant(0, getPointerTy(), true),
556 InFlag = Chain.getValue(1);
558 // Handle result values, copying them out of physregs into vregs that we
560 return LowerCallResult(Chain, InFlag, CallConv, isVarArg, Ins, dl,
564 /// LowerCallResult - Lower the result values of a call into the
565 /// appropriate copies out of appropriate physical registers.
568 MSP430TargetLowering::LowerCallResult(SDValue Chain, SDValue InFlag,
569 CallingConv::ID CallConv, bool isVarArg,
570 const SmallVectorImpl<ISD::InputArg> &Ins,
571 DebugLoc dl, SelectionDAG &DAG,
572 SmallVectorImpl<SDValue> &InVals) const {
574 // Assign locations to each value returned by this call.
575 SmallVector<CCValAssign, 16> RVLocs;
576 CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(),
577 getTargetMachine(), RVLocs, *DAG.getContext());
579 CCInfo.AnalyzeCallResult(Ins, RetCC_MSP430);
581 // Copy all of the result registers out of their specified physreg.
582 for (unsigned i = 0; i != RVLocs.size(); ++i) {
583 Chain = DAG.getCopyFromReg(Chain, dl, RVLocs[i].getLocReg(),
584 RVLocs[i].getValVT(), InFlag).getValue(1);
585 InFlag = Chain.getValue(2);
586 InVals.push_back(Chain.getValue(0));
592 SDValue MSP430TargetLowering::LowerShifts(SDValue Op,
593 SelectionDAG &DAG) const {
594 unsigned Opc = Op.getOpcode();
595 SDNode* N = Op.getNode();
596 EVT VT = Op.getValueType();
597 DebugLoc dl = N->getDebugLoc();
599 // Expand non-constant shifts to loops:
600 if (!isa<ConstantSDNode>(N->getOperand(1)))
603 assert(0 && "Invalid shift opcode!");
605 return DAG.getNode(MSP430ISD::SHL, dl,
606 VT, N->getOperand(0), N->getOperand(1));
608 return DAG.getNode(MSP430ISD::SRA, dl,
609 VT, N->getOperand(0), N->getOperand(1));
611 return DAG.getNode(MSP430ISD::SRL, dl,
612 VT, N->getOperand(0), N->getOperand(1));
615 uint64_t ShiftAmount = cast<ConstantSDNode>(N->getOperand(1))->getZExtValue();
617 // Expand the stuff into sequence of shifts.
618 // FIXME: for some shift amounts this might be done better!
619 // E.g.: foo >> (8 + N) => sxt(swpb(foo)) >> N
620 SDValue Victim = N->getOperand(0);
622 if (Opc == ISD::SRL && ShiftAmount) {
623 // Emit a special goodness here:
624 // srl A, 1 => clrc; rrc A
625 Victim = DAG.getNode(MSP430ISD::RRC, dl, VT, Victim);
629 while (ShiftAmount--)
630 Victim = DAG.getNode((Opc == ISD::SHL ? MSP430ISD::RLA : MSP430ISD::RRA),
636 SDValue MSP430TargetLowering::LowerGlobalAddress(SDValue Op,
637 SelectionDAG &DAG) const {
638 const GlobalValue *GV = cast<GlobalAddressSDNode>(Op)->getGlobal();
639 int64_t Offset = cast<GlobalAddressSDNode>(Op)->getOffset();
641 // Create the TargetGlobalAddress node, folding in the constant offset.
642 SDValue Result = DAG.getTargetGlobalAddress(GV, Op.getDebugLoc(),
643 getPointerTy(), Offset);
644 return DAG.getNode(MSP430ISD::Wrapper, Op.getDebugLoc(),
645 getPointerTy(), Result);
648 SDValue MSP430TargetLowering::LowerExternalSymbol(SDValue Op,
649 SelectionDAG &DAG) const {
650 DebugLoc dl = Op.getDebugLoc();
651 const char *Sym = cast<ExternalSymbolSDNode>(Op)->getSymbol();
652 SDValue Result = DAG.getTargetExternalSymbol(Sym, getPointerTy());
654 return DAG.getNode(MSP430ISD::Wrapper, dl, getPointerTy(), Result);;
657 SDValue MSP430TargetLowering::LowerBlockAddress(SDValue Op,
658 SelectionDAG &DAG) const {
659 DebugLoc dl = Op.getDebugLoc();
660 const BlockAddress *BA = cast<BlockAddressSDNode>(Op)->getBlockAddress();
661 SDValue Result = DAG.getBlockAddress(BA, getPointerTy(), /*isTarget=*/true);
663 return DAG.getNode(MSP430ISD::Wrapper, dl, getPointerTy(), Result);;
666 static SDValue EmitCMP(SDValue &LHS, SDValue &RHS, SDValue &TargetCC,
668 DebugLoc dl, SelectionDAG &DAG) {
669 // FIXME: Handle bittests someday
670 assert(!LHS.getValueType().isFloatingPoint() && "We don't handle FP yet");
672 // FIXME: Handle jump negative someday
673 MSP430CC::CondCodes TCC = MSP430CC::COND_INVALID;
675 default: llvm_unreachable("Invalid integer condition!");
677 TCC = MSP430CC::COND_E; // aka COND_Z
678 // Minor optimization: if LHS is a constant, swap operands, then the
679 // constant can be folded into comparison.
680 if (LHS.getOpcode() == ISD::Constant)
684 TCC = MSP430CC::COND_NE; // aka COND_NZ
685 // Minor optimization: if LHS is a constant, swap operands, then the
686 // constant can be folded into comparison.
687 if (LHS.getOpcode() == ISD::Constant)
691 std::swap(LHS, RHS); // FALLTHROUGH
693 // Turn lhs u>= rhs with lhs constant into rhs u< lhs+1, this allows us to
694 // fold constant into instruction.
695 if (const ConstantSDNode * C = dyn_cast<ConstantSDNode>(LHS)) {
697 RHS = DAG.getConstant(C->getSExtValue() + 1, C->getValueType(0));
698 TCC = MSP430CC::COND_LO;
701 TCC = MSP430CC::COND_HS; // aka COND_C
704 std::swap(LHS, RHS); // FALLTHROUGH
706 // Turn lhs u< rhs with lhs constant into rhs u>= lhs+1, this allows us to
707 // fold constant into instruction.
708 if (const ConstantSDNode * C = dyn_cast<ConstantSDNode>(LHS)) {
710 RHS = DAG.getConstant(C->getSExtValue() + 1, C->getValueType(0));
711 TCC = MSP430CC::COND_HS;
714 TCC = MSP430CC::COND_LO; // aka COND_NC
717 std::swap(LHS, RHS); // FALLTHROUGH
719 // Turn lhs >= rhs with lhs constant into rhs < lhs+1, this allows us to
720 // fold constant into instruction.
721 if (const ConstantSDNode * C = dyn_cast<ConstantSDNode>(LHS)) {
723 RHS = DAG.getConstant(C->getSExtValue() + 1, C->getValueType(0));
724 TCC = MSP430CC::COND_L;
727 TCC = MSP430CC::COND_GE;
730 std::swap(LHS, RHS); // FALLTHROUGH
732 // Turn lhs < rhs with lhs constant into rhs >= lhs+1, this allows us to
733 // fold constant into instruction.
734 if (const ConstantSDNode * C = dyn_cast<ConstantSDNode>(LHS)) {
736 RHS = DAG.getConstant(C->getSExtValue() + 1, C->getValueType(0));
737 TCC = MSP430CC::COND_GE;
740 TCC = MSP430CC::COND_L;
744 TargetCC = DAG.getConstant(TCC, MVT::i8);
745 return DAG.getNode(MSP430ISD::CMP, dl, MVT::Glue, LHS, RHS);
749 SDValue MSP430TargetLowering::LowerBR_CC(SDValue Op, SelectionDAG &DAG) const {
750 SDValue Chain = Op.getOperand(0);
751 ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(1))->get();
752 SDValue LHS = Op.getOperand(2);
753 SDValue RHS = Op.getOperand(3);
754 SDValue Dest = Op.getOperand(4);
755 DebugLoc dl = Op.getDebugLoc();
758 SDValue Flag = EmitCMP(LHS, RHS, TargetCC, CC, dl, DAG);
760 return DAG.getNode(MSP430ISD::BR_CC, dl, Op.getValueType(),
761 Chain, Dest, TargetCC, Flag);
764 SDValue MSP430TargetLowering::LowerSETCC(SDValue Op, SelectionDAG &DAG) const {
765 SDValue LHS = Op.getOperand(0);
766 SDValue RHS = Op.getOperand(1);
767 DebugLoc dl = Op.getDebugLoc();
769 // If we are doing an AND and testing against zero, then the CMP
770 // will not be generated. The AND (or BIT) will generate the condition codes,
771 // but they are different from CMP.
772 // FIXME: since we're doing a post-processing, use a pseudoinstr here, so
773 // lowering & isel wouldn't diverge.
775 if (ConstantSDNode *RHSC = dyn_cast<ConstantSDNode>(RHS)) {
776 if (RHSC->isNullValue() && LHS.hasOneUse() &&
777 (LHS.getOpcode() == ISD::AND ||
778 (LHS.getOpcode() == ISD::TRUNCATE &&
779 LHS.getOperand(0).getOpcode() == ISD::AND))) {
783 ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(2))->get();
785 SDValue Flag = EmitCMP(LHS, RHS, TargetCC, CC, dl, DAG);
787 // Get the condition codes directly from the status register, if its easy.
788 // Otherwise a branch will be generated. Note that the AND and BIT
789 // instructions generate different flags than CMP, the carry bit can be used
794 switch (cast<ConstantSDNode>(TargetCC)->getZExtValue()) {
798 case MSP430CC::COND_HS:
799 // Res = SRW & 1, no processing is required
801 case MSP430CC::COND_LO:
805 case MSP430CC::COND_NE:
807 // C = ~Z, thus Res = SRW & 1, no processing is required
809 // Res = ~((SRW >> 1) & 1)
814 case MSP430CC::COND_E:
816 // C = ~Z for AND instruction, thus we can put Res = ~(SRW & 1), however,
817 // Res = (SRW >> 1) & 1 is 1 word shorter.
820 EVT VT = Op.getValueType();
821 SDValue One = DAG.getConstant(1, VT);
823 SDValue SR = DAG.getCopyFromReg(DAG.getEntryNode(), dl, MSP430::SRW,
826 // FIXME: somewhere this is turned into a SRL, lower it MSP specific?
827 SR = DAG.getNode(ISD::SRA, dl, MVT::i16, SR, One);
828 SR = DAG.getNode(ISD::AND, dl, MVT::i16, SR, One);
830 SR = DAG.getNode(ISD::XOR, dl, MVT::i16, SR, One);
833 SDValue Zero = DAG.getConstant(0, VT);
834 SDVTList VTs = DAG.getVTList(Op.getValueType(), MVT::Glue);
835 SmallVector<SDValue, 4> Ops;
838 Ops.push_back(TargetCC);
840 return DAG.getNode(MSP430ISD::SELECT_CC, dl, VTs, &Ops[0], Ops.size());
844 SDValue MSP430TargetLowering::LowerSELECT_CC(SDValue Op,
845 SelectionDAG &DAG) const {
846 SDValue LHS = Op.getOperand(0);
847 SDValue RHS = Op.getOperand(1);
848 SDValue TrueV = Op.getOperand(2);
849 SDValue FalseV = Op.getOperand(3);
850 ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(4))->get();
851 DebugLoc dl = Op.getDebugLoc();
854 SDValue Flag = EmitCMP(LHS, RHS, TargetCC, CC, dl, DAG);
856 SDVTList VTs = DAG.getVTList(Op.getValueType(), MVT::Glue);
857 SmallVector<SDValue, 4> Ops;
858 Ops.push_back(TrueV);
859 Ops.push_back(FalseV);
860 Ops.push_back(TargetCC);
863 return DAG.getNode(MSP430ISD::SELECT_CC, dl, VTs, &Ops[0], Ops.size());
866 SDValue MSP430TargetLowering::LowerSIGN_EXTEND(SDValue Op,
867 SelectionDAG &DAG) const {
868 SDValue Val = Op.getOperand(0);
869 EVT VT = Op.getValueType();
870 DebugLoc dl = Op.getDebugLoc();
872 assert(VT == MVT::i16 && "Only support i16 for now!");
874 return DAG.getNode(ISD::SIGN_EXTEND_INREG, dl, VT,
875 DAG.getNode(ISD::ANY_EXTEND, dl, VT, Val),
876 DAG.getValueType(Val.getValueType()));
880 MSP430TargetLowering::getReturnAddressFrameIndex(SelectionDAG &DAG) const {
881 MachineFunction &MF = DAG.getMachineFunction();
882 MSP430MachineFunctionInfo *FuncInfo = MF.getInfo<MSP430MachineFunctionInfo>();
883 int ReturnAddrIndex = FuncInfo->getRAIndex();
885 if (ReturnAddrIndex == 0) {
886 // Set up a frame object for the return address.
887 uint64_t SlotSize = TD->getPointerSize();
888 ReturnAddrIndex = MF.getFrameInfo()->CreateFixedObject(SlotSize, -SlotSize,
890 FuncInfo->setRAIndex(ReturnAddrIndex);
893 return DAG.getFrameIndex(ReturnAddrIndex, getPointerTy());
896 SDValue MSP430TargetLowering::LowerRETURNADDR(SDValue Op,
897 SelectionDAG &DAG) const {
898 MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo();
899 MFI->setReturnAddressIsTaken(true);
901 unsigned Depth = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
902 DebugLoc dl = Op.getDebugLoc();
905 SDValue FrameAddr = LowerFRAMEADDR(Op, DAG);
907 DAG.getConstant(TD->getPointerSize(), MVT::i16);
908 return DAG.getLoad(getPointerTy(), dl, DAG.getEntryNode(),
909 DAG.getNode(ISD::ADD, dl, getPointerTy(),
911 MachinePointerInfo(), false, false, 0);
914 // Just load the return address.
915 SDValue RetAddrFI = getReturnAddressFrameIndex(DAG);
916 return DAG.getLoad(getPointerTy(), dl, DAG.getEntryNode(),
917 RetAddrFI, MachinePointerInfo(), false, false, 0);
920 SDValue MSP430TargetLowering::LowerFRAMEADDR(SDValue Op,
921 SelectionDAG &DAG) const {
922 MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo();
923 MFI->setFrameAddressIsTaken(true);
925 EVT VT = Op.getValueType();
926 DebugLoc dl = Op.getDebugLoc(); // FIXME probably not meaningful
927 unsigned Depth = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
928 SDValue FrameAddr = DAG.getCopyFromReg(DAG.getEntryNode(), dl,
931 FrameAddr = DAG.getLoad(VT, dl, DAG.getEntryNode(), FrameAddr,
932 MachinePointerInfo(),
937 /// getPostIndexedAddressParts - returns true by value, base pointer and
938 /// offset pointer and addressing mode by reference if this node can be
939 /// combined with a load / store to form a post-indexed load / store.
940 bool MSP430TargetLowering::getPostIndexedAddressParts(SDNode *N, SDNode *Op,
943 ISD::MemIndexedMode &AM,
944 SelectionDAG &DAG) const {
946 LoadSDNode *LD = cast<LoadSDNode>(N);
947 if (LD->getExtensionType() != ISD::NON_EXTLOAD)
950 EVT VT = LD->getMemoryVT();
951 if (VT != MVT::i8 && VT != MVT::i16)
954 if (Op->getOpcode() != ISD::ADD)
957 if (ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(Op->getOperand(1))) {
958 uint64_t RHSC = RHS->getZExtValue();
959 if ((VT == MVT::i16 && RHSC != 2) ||
960 (VT == MVT::i8 && RHSC != 1))
963 Base = Op->getOperand(0);
964 Offset = DAG.getConstant(RHSC, VT);
973 const char *MSP430TargetLowering::getTargetNodeName(unsigned Opcode) const {
975 default: return NULL;
976 case MSP430ISD::RET_FLAG: return "MSP430ISD::RET_FLAG";
977 case MSP430ISD::RETI_FLAG: return "MSP430ISD::RETI_FLAG";
978 case MSP430ISD::RRA: return "MSP430ISD::RRA";
979 case MSP430ISD::RLA: return "MSP430ISD::RLA";
980 case MSP430ISD::RRC: return "MSP430ISD::RRC";
981 case MSP430ISD::CALL: return "MSP430ISD::CALL";
982 case MSP430ISD::Wrapper: return "MSP430ISD::Wrapper";
983 case MSP430ISD::BR_CC: return "MSP430ISD::BR_CC";
984 case MSP430ISD::CMP: return "MSP430ISD::CMP";
985 case MSP430ISD::SELECT_CC: return "MSP430ISD::SELECT_CC";
986 case MSP430ISD::SHL: return "MSP430ISD::SHL";
987 case MSP430ISD::SRA: return "MSP430ISD::SRA";
991 bool MSP430TargetLowering::isTruncateFree(Type *Ty1,
993 if (!Ty1->isIntegerTy() || !Ty2->isIntegerTy())
996 return (Ty1->getPrimitiveSizeInBits() > Ty2->getPrimitiveSizeInBits());
999 bool MSP430TargetLowering::isTruncateFree(EVT VT1, EVT VT2) const {
1000 if (!VT1.isInteger() || !VT2.isInteger())
1003 return (VT1.getSizeInBits() > VT2.getSizeInBits());
1006 bool MSP430TargetLowering::isZExtFree(Type *Ty1, Type *Ty2) const {
1007 // MSP430 implicitly zero-extends 8-bit results in 16-bit registers.
1008 return 0 && Ty1->isIntegerTy(8) && Ty2->isIntegerTy(16);
1011 bool MSP430TargetLowering::isZExtFree(EVT VT1, EVT VT2) const {
1012 // MSP430 implicitly zero-extends 8-bit results in 16-bit registers.
1013 return 0 && VT1 == MVT::i8 && VT2 == MVT::i16;
1016 //===----------------------------------------------------------------------===//
1017 // Other Lowering Code
1018 //===----------------------------------------------------------------------===//
1021 MSP430TargetLowering::EmitShiftInstr(MachineInstr *MI,
1022 MachineBasicBlock *BB) const {
1023 MachineFunction *F = BB->getParent();
1024 MachineRegisterInfo &RI = F->getRegInfo();
1025 DebugLoc dl = MI->getDebugLoc();
1026 const TargetInstrInfo &TII = *getTargetMachine().getInstrInfo();
1029 const TargetRegisterClass * RC;
1030 switch (MI->getOpcode()) {
1032 assert(0 && "Invalid shift opcode!");
1034 Opc = MSP430::SHL8r1;
1035 RC = MSP430::GR8RegisterClass;
1038 Opc = MSP430::SHL16r1;
1039 RC = MSP430::GR16RegisterClass;
1042 Opc = MSP430::SAR8r1;
1043 RC = MSP430::GR8RegisterClass;
1046 Opc = MSP430::SAR16r1;
1047 RC = MSP430::GR16RegisterClass;
1050 Opc = MSP430::SAR8r1c;
1051 RC = MSP430::GR8RegisterClass;
1054 Opc = MSP430::SAR16r1c;
1055 RC = MSP430::GR16RegisterClass;
1059 const BasicBlock *LLVM_BB = BB->getBasicBlock();
1060 MachineFunction::iterator I = BB;
1063 // Create loop block
1064 MachineBasicBlock *LoopBB = F->CreateMachineBasicBlock(LLVM_BB);
1065 MachineBasicBlock *RemBB = F->CreateMachineBasicBlock(LLVM_BB);
1067 F->insert(I, LoopBB);
1068 F->insert(I, RemBB);
1070 // Update machine-CFG edges by transferring all successors of the current
1071 // block to the block containing instructions after shift.
1072 RemBB->splice(RemBB->begin(), BB,
1073 llvm::next(MachineBasicBlock::iterator(MI)),
1075 RemBB->transferSuccessorsAndUpdatePHIs(BB);
1077 // Add adges BB => LoopBB => RemBB, BB => RemBB, LoopBB => LoopBB
1078 BB->addSuccessor(LoopBB);
1079 BB->addSuccessor(RemBB);
1080 LoopBB->addSuccessor(RemBB);
1081 LoopBB->addSuccessor(LoopBB);
1083 unsigned ShiftAmtReg = RI.createVirtualRegister(MSP430::GR8RegisterClass);
1084 unsigned ShiftAmtReg2 = RI.createVirtualRegister(MSP430::GR8RegisterClass);
1085 unsigned ShiftReg = RI.createVirtualRegister(RC);
1086 unsigned ShiftReg2 = RI.createVirtualRegister(RC);
1087 unsigned ShiftAmtSrcReg = MI->getOperand(2).getReg();
1088 unsigned SrcReg = MI->getOperand(1).getReg();
1089 unsigned DstReg = MI->getOperand(0).getReg();
1094 BuildMI(BB, dl, TII.get(MSP430::CMP8ri))
1095 .addReg(ShiftAmtSrcReg).addImm(0);
1096 BuildMI(BB, dl, TII.get(MSP430::JCC))
1098 .addImm(MSP430CC::COND_E);
1101 // ShiftReg = phi [%SrcReg, BB], [%ShiftReg2, LoopBB]
1102 // ShiftAmt = phi [%N, BB], [%ShiftAmt2, LoopBB]
1103 // ShiftReg2 = shift ShiftReg
1104 // ShiftAmt2 = ShiftAmt - 1;
1105 BuildMI(LoopBB, dl, TII.get(MSP430::PHI), ShiftReg)
1106 .addReg(SrcReg).addMBB(BB)
1107 .addReg(ShiftReg2).addMBB(LoopBB);
1108 BuildMI(LoopBB, dl, TII.get(MSP430::PHI), ShiftAmtReg)
1109 .addReg(ShiftAmtSrcReg).addMBB(BB)
1110 .addReg(ShiftAmtReg2).addMBB(LoopBB);
1111 BuildMI(LoopBB, dl, TII.get(Opc), ShiftReg2)
1113 BuildMI(LoopBB, dl, TII.get(MSP430::SUB8ri), ShiftAmtReg2)
1114 .addReg(ShiftAmtReg).addImm(1);
1115 BuildMI(LoopBB, dl, TII.get(MSP430::JCC))
1117 .addImm(MSP430CC::COND_NE);
1120 // DestReg = phi [%SrcReg, BB], [%ShiftReg, LoopBB]
1121 BuildMI(*RemBB, RemBB->begin(), dl, TII.get(MSP430::PHI), DstReg)
1122 .addReg(SrcReg).addMBB(BB)
1123 .addReg(ShiftReg2).addMBB(LoopBB);
1125 MI->eraseFromParent(); // The pseudo instruction is gone now.
1130 MSP430TargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
1131 MachineBasicBlock *BB) const {
1132 unsigned Opc = MI->getOpcode();
1134 if (Opc == MSP430::Shl8 || Opc == MSP430::Shl16 ||
1135 Opc == MSP430::Sra8 || Opc == MSP430::Sra16 ||
1136 Opc == MSP430::Srl8 || Opc == MSP430::Srl16)
1137 return EmitShiftInstr(MI, BB);
1139 const TargetInstrInfo &TII = *getTargetMachine().getInstrInfo();
1140 DebugLoc dl = MI->getDebugLoc();
1142 assert((Opc == MSP430::Select16 || Opc == MSP430::Select8) &&
1143 "Unexpected instr type to insert");
1145 // To "insert" a SELECT instruction, we actually have to insert the diamond
1146 // control-flow pattern. The incoming instruction knows the destination vreg
1147 // to set, the condition code register to branch on, the true/false values to
1148 // select between, and a branch opcode to use.
1149 const BasicBlock *LLVM_BB = BB->getBasicBlock();
1150 MachineFunction::iterator I = BB;
1156 // cmpTY ccX, r1, r2
1158 // fallthrough --> copy0MBB
1159 MachineBasicBlock *thisMBB = BB;
1160 MachineFunction *F = BB->getParent();
1161 MachineBasicBlock *copy0MBB = F->CreateMachineBasicBlock(LLVM_BB);
1162 MachineBasicBlock *copy1MBB = F->CreateMachineBasicBlock(LLVM_BB);
1163 F->insert(I, copy0MBB);
1164 F->insert(I, copy1MBB);
1165 // Update machine-CFG edges by transferring all successors of the current
1166 // block to the new block which will contain the Phi node for the select.
1167 copy1MBB->splice(copy1MBB->begin(), BB,
1168 llvm::next(MachineBasicBlock::iterator(MI)),
1170 copy1MBB->transferSuccessorsAndUpdatePHIs(BB);
1171 // Next, add the true and fallthrough blocks as its successors.
1172 BB->addSuccessor(copy0MBB);
1173 BB->addSuccessor(copy1MBB);
1175 BuildMI(BB, dl, TII.get(MSP430::JCC))
1177 .addImm(MI->getOperand(3).getImm());
1180 // %FalseValue = ...
1181 // # fallthrough to copy1MBB
1184 // Update machine-CFG edges
1185 BB->addSuccessor(copy1MBB);
1188 // %Result = phi [ %FalseValue, copy0MBB ], [ %TrueValue, thisMBB ]
1191 BuildMI(*BB, BB->begin(), dl, TII.get(MSP430::PHI),
1192 MI->getOperand(0).getReg())
1193 .addReg(MI->getOperand(2).getReg()).addMBB(copy0MBB)
1194 .addReg(MI->getOperand(1).getReg()).addMBB(thisMBB);
1196 MI->eraseFromParent(); // The pseudo instruction is gone now.