SparcISelLowering.cpp revision 0329466b6b4927f4e6f5d144891fef06a027fec5
1//===-- SparcISelLowering.cpp - Sparc DAG Lowering Implementation ---------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file implements the interfaces that Sparc uses to lower LLVM code into a
11// selection DAG.
12//
13//===----------------------------------------------------------------------===//
14
15#include "SparcISelLowering.h"
16#include "SparcTargetMachine.h"
17#include "llvm/Function.h"
18#include "llvm/CodeGen/CallingConvLower.h"
19#include "llvm/CodeGen/MachineFrameInfo.h"
20#include "llvm/CodeGen/MachineFunction.h"
21#include "llvm/CodeGen/MachineInstrBuilder.h"
22#include "llvm/CodeGen/MachineRegisterInfo.h"
23#include "llvm/CodeGen/SelectionDAG.h"
24#include "llvm/ADT/VectorExtras.h"
25using namespace llvm;
26
27
28//===----------------------------------------------------------------------===//
29// Calling Convention Implementation
30//===----------------------------------------------------------------------===//
31
32#include "SparcGenCallingConv.inc"
33
34static SDValue LowerRET(SDValue Op, SelectionDAG &DAG) {
35  // CCValAssign - represent the assignment of the return value to locations.
36  SmallVector<CCValAssign, 16> RVLocs;
37  unsigned CC = DAG.getMachineFunction().getFunction()->getCallingConv();
38  bool isVarArg = DAG.getMachineFunction().getFunction()->isVarArg();
39
40  // CCState - Info about the registers and stack slot.
41  CCState CCInfo(CC, isVarArg, DAG.getTarget(), RVLocs);
42
43  // Analize return values of ISD::RET
44  CCInfo.AnalyzeReturn(Op.getNode(), RetCC_Sparc32);
45
46  // If this is the first return lowered for this function, add the regs to the
47  // liveout set for the function.
48  if (DAG.getMachineFunction().getRegInfo().liveout_empty()) {
49    for (unsigned i = 0; i != RVLocs.size(); ++i)
50      if (RVLocs[i].isRegLoc())
51        DAG.getMachineFunction().getRegInfo().addLiveOut(RVLocs[i].getLocReg());
52  }
53
54  SDValue Chain = Op.getOperand(0);
55  SDValue Flag;
56
57  // Copy the result values into the output registers.
58  for (unsigned i = 0; i != RVLocs.size(); ++i) {
59    CCValAssign &VA = RVLocs[i];
60    assert(VA.isRegLoc() && "Can only return in registers!");
61
62    // ISD::RET => ret chain, (regnum1,val1), ...
63    // So i*2+1 index only the regnums.
64    Chain = DAG.getCopyToReg(Chain, VA.getLocReg(), Op.getOperand(i*2+1), Flag);
65
66    // Guarantee that all emitted copies are stuck together with flags.
67    Flag = Chain.getValue(1);
68  }
69
70  if (Flag.getNode())
71    return DAG.getNode(SPISD::RET_FLAG, MVT::Other, Chain, Flag);
72  return DAG.getNode(SPISD::RET_FLAG, MVT::Other, Chain);
73}
74
75/// LowerArguments - V8 uses a very simple ABI, where all values are passed in
76/// either one or two GPRs, including FP values.  TODO: we should pass FP values
77/// in FP registers for fastcc functions.
78void
79SparcTargetLowering::LowerArguments(Function &F, SelectionDAG &DAG,
80                                    SmallVectorImpl<SDValue> &ArgValues) {
81  MachineFunction &MF = DAG.getMachineFunction();
82  MachineRegisterInfo &RegInfo = MF.getRegInfo();
83
84  static const unsigned ArgRegs[] = {
85    SP::I0, SP::I1, SP::I2, SP::I3, SP::I4, SP::I5
86  };
87
88  const unsigned *CurArgReg = ArgRegs, *ArgRegEnd = ArgRegs+6;
89  unsigned ArgOffset = 68;
90
91  SDValue Root = DAG.getRoot();
92  std::vector<SDValue> OutChains;
93
94  for (Function::arg_iterator I = F.arg_begin(), E = F.arg_end(); I != E; ++I) {
95    MVT ObjectVT = getValueType(I->getType());
96
97    switch (ObjectVT.getSimpleVT()) {
98    default: assert(0 && "Unhandled argument type!");
99    case MVT::i1:
100    case MVT::i8:
101    case MVT::i16:
102    case MVT::i32:
103      if (I->use_empty()) {                // Argument is dead.
104        if (CurArgReg < ArgRegEnd) ++CurArgReg;
105        ArgValues.push_back(DAG.getNode(ISD::UNDEF, ObjectVT));
106      } else if (CurArgReg < ArgRegEnd) {  // Lives in an incoming GPR
107        unsigned VReg = RegInfo.createVirtualRegister(&SP::IntRegsRegClass);
108        MF.getRegInfo().addLiveIn(*CurArgReg++, VReg);
109        SDValue Arg = DAG.getCopyFromReg(Root, VReg, MVT::i32);
110        if (ObjectVT != MVT::i32) {
111          unsigned AssertOp = ISD::AssertSext;
112          Arg = DAG.getNode(AssertOp, MVT::i32, Arg,
113                            DAG.getValueType(ObjectVT));
114          Arg = DAG.getNode(ISD::TRUNCATE, ObjectVT, Arg);
115        }
116        ArgValues.push_back(Arg);
117      } else {
118        int FrameIdx = MF.getFrameInfo()->CreateFixedObject(4, ArgOffset);
119        SDValue FIPtr = DAG.getFrameIndex(FrameIdx, MVT::i32);
120        SDValue Load;
121        if (ObjectVT == MVT::i32) {
122          Load = DAG.getLoad(MVT::i32, Root, FIPtr, NULL, 0);
123        } else {
124          ISD::LoadExtType LoadOp = ISD::SEXTLOAD;
125
126          // Sparc is big endian, so add an offset based on the ObjectVT.
127          unsigned Offset = 4-std::max(1U, ObjectVT.getSizeInBits()/8);
128          FIPtr = DAG.getNode(ISD::ADD, MVT::i32, FIPtr,
129                              DAG.getConstant(Offset, MVT::i32));
130          Load = DAG.getExtLoad(LoadOp, MVT::i32, Root, FIPtr,
131                                NULL, 0, ObjectVT);
132          Load = DAG.getNode(ISD::TRUNCATE, ObjectVT, Load);
133        }
134        ArgValues.push_back(Load);
135      }
136
137      ArgOffset += 4;
138      break;
139    case MVT::f32:
140      if (I->use_empty()) {                // Argument is dead.
141        if (CurArgReg < ArgRegEnd) ++CurArgReg;
142        ArgValues.push_back(DAG.getNode(ISD::UNDEF, ObjectVT));
143      } else if (CurArgReg < ArgRegEnd) {  // Lives in an incoming GPR
144        // FP value is passed in an integer register.
145        unsigned VReg = RegInfo.createVirtualRegister(&SP::IntRegsRegClass);
146        MF.getRegInfo().addLiveIn(*CurArgReg++, VReg);
147        SDValue Arg = DAG.getCopyFromReg(Root, VReg, MVT::i32);
148
149        Arg = DAG.getNode(ISD::BIT_CONVERT, MVT::f32, Arg);
150        ArgValues.push_back(Arg);
151      } else {
152        int FrameIdx = MF.getFrameInfo()->CreateFixedObject(4, ArgOffset);
153        SDValue FIPtr = DAG.getFrameIndex(FrameIdx, MVT::i32);
154        SDValue Load = DAG.getLoad(MVT::f32, Root, FIPtr, NULL, 0);
155        ArgValues.push_back(Load);
156      }
157      ArgOffset += 4;
158      break;
159
160    case MVT::i64:
161    case MVT::f64:
162      if (I->use_empty()) {                // Argument is dead.
163        if (CurArgReg < ArgRegEnd) ++CurArgReg;
164        if (CurArgReg < ArgRegEnd) ++CurArgReg;
165        ArgValues.push_back(DAG.getNode(ISD::UNDEF, ObjectVT));
166      } else {
167        SDValue HiVal;
168        if (CurArgReg < ArgRegEnd) {  // Lives in an incoming GPR
169          unsigned VRegHi = RegInfo.createVirtualRegister(&SP::IntRegsRegClass);
170          MF.getRegInfo().addLiveIn(*CurArgReg++, VRegHi);
171          HiVal = DAG.getCopyFromReg(Root, VRegHi, MVT::i32);
172        } else {
173          int FrameIdx = MF.getFrameInfo()->CreateFixedObject(4, ArgOffset);
174          SDValue FIPtr = DAG.getFrameIndex(FrameIdx, MVT::i32);
175          HiVal = DAG.getLoad(MVT::i32, Root, FIPtr, NULL, 0);
176        }
177
178        SDValue LoVal;
179        if (CurArgReg < ArgRegEnd) {  // Lives in an incoming GPR
180          unsigned VRegLo = RegInfo.createVirtualRegister(&SP::IntRegsRegClass);
181          MF.getRegInfo().addLiveIn(*CurArgReg++, VRegLo);
182          LoVal = DAG.getCopyFromReg(Root, VRegLo, MVT::i32);
183        } else {
184          int FrameIdx = MF.getFrameInfo()->CreateFixedObject(4, ArgOffset+4);
185          SDValue FIPtr = DAG.getFrameIndex(FrameIdx, MVT::i32);
186          LoVal = DAG.getLoad(MVT::i32, Root, FIPtr, NULL, 0);
187        }
188
189        // Compose the two halves together into an i64 unit.
190        SDValue WholeValue =
191          DAG.getNode(ISD::BUILD_PAIR, MVT::i64, LoVal, HiVal);
192
193        // If we want a double, do a bit convert.
194        if (ObjectVT == MVT::f64)
195          WholeValue = DAG.getNode(ISD::BIT_CONVERT, MVT::f64, WholeValue);
196
197        ArgValues.push_back(WholeValue);
198      }
199      ArgOffset += 8;
200      break;
201    }
202  }
203
204  // Store remaining ArgRegs to the stack if this is a varargs function.
205  if (F.isVarArg()) {
206    // Remember the vararg offset for the va_start implementation.
207    VarArgsFrameOffset = ArgOffset;
208
209    for (; CurArgReg != ArgRegEnd; ++CurArgReg) {
210      unsigned VReg = RegInfo.createVirtualRegister(&SP::IntRegsRegClass);
211      MF.getRegInfo().addLiveIn(*CurArgReg, VReg);
212      SDValue Arg = DAG.getCopyFromReg(DAG.getRoot(), VReg, MVT::i32);
213
214      int FrameIdx = MF.getFrameInfo()->CreateFixedObject(4, ArgOffset);
215      SDValue FIPtr = DAG.getFrameIndex(FrameIdx, MVT::i32);
216
217      OutChains.push_back(DAG.getStore(DAG.getRoot(), Arg, FIPtr, NULL, 0));
218      ArgOffset += 4;
219    }
220  }
221
222  if (!OutChains.empty())
223    DAG.setRoot(DAG.getNode(ISD::TokenFactor, MVT::Other,
224                            &OutChains[0], OutChains.size()));
225}
226
227static SDValue LowerCALL(SDValue Op, SelectionDAG &DAG) {
228  CallSDNode *TheCall = cast<CallSDNode>(Op.getNode());
229  unsigned CallingConv = TheCall->getCallingConv();
230  SDValue Chain = TheCall->getChain();
231  SDValue Callee = TheCall->getCallee();
232  bool isVarArg = TheCall->isVarArg();
233
234#if 0
235  // Analyze operands of the call, assigning locations to each operand.
236  SmallVector<CCValAssign, 16> ArgLocs;
237  CCState CCInfo(CallingConv, isVarArg, DAG.getTarget(), ArgLocs);
238  CCInfo.AnalyzeCallOperands(Op.getNode(), CC_Sparc32);
239
240  // Get the size of the outgoing arguments stack space requirement.
241  unsigned ArgsSize = CCInfo.getNextStackOffset();
242  // FIXME: We can't use this until f64 is known to take two GPRs.
243#else
244  (void)CC_Sparc32;
245
246  // Count the size of the outgoing arguments.
247  unsigned ArgsSize = 0;
248  for (unsigned i = 0, e = TheCall->getNumArgs(); i != e; ++i) {
249    switch (TheCall->getArg(i).getValueType().getSimpleVT()) {
250      default: assert(0 && "Unknown value type!");
251      case MVT::i1:
252      case MVT::i8:
253      case MVT::i16:
254      case MVT::i32:
255      case MVT::f32:
256        ArgsSize += 4;
257        break;
258      case MVT::i64:
259      case MVT::f64:
260        ArgsSize += 8;
261        break;
262    }
263  }
264  if (ArgsSize > 4*6)
265    ArgsSize -= 4*6;    // Space for first 6 arguments is prereserved.
266  else
267    ArgsSize = 0;
268#endif
269
270  // Keep stack frames 8-byte aligned.
271  ArgsSize = (ArgsSize+7) & ~7;
272
273  Chain = DAG.getCALLSEQ_START(Chain, DAG.getIntPtrConstant(ArgsSize, true));
274
275  SmallVector<std::pair<unsigned, SDValue>, 8> RegsToPass;
276  SmallVector<SDValue, 8> MemOpChains;
277
278#if 0
279  // Walk the register/memloc assignments, inserting copies/loads.
280  for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
281    CCValAssign &VA = ArgLocs[i];
282
283    // Arguments start after the 5 first operands of ISD::CALL
284    SDValue Arg = TheCall->getArg(i);
285
286    // Promote the value if needed.
287    switch (VA.getLocInfo()) {
288    default: assert(0 && "Unknown loc info!");
289    case CCValAssign::Full: break;
290    case CCValAssign::SExt:
291      Arg = DAG.getNode(ISD::SIGN_EXTEND, VA.getLocVT(), Arg);
292      break;
293    case CCValAssign::ZExt:
294      Arg = DAG.getNode(ISD::ZERO_EXTEND, VA.getLocVT(), Arg);
295      break;
296    case CCValAssign::AExt:
297      Arg = DAG.getNode(ISD::ANY_EXTEND, VA.getLocVT(), Arg);
298      break;
299    }
300
301    // Arguments that can be passed on register must be kept at
302    // RegsToPass vector
303    if (VA.isRegLoc()) {
304      RegsToPass.push_back(std::make_pair(VA.getLocReg(), Arg));
305      continue;
306    }
307
308    assert(VA.isMemLoc());
309
310    // Create a store off the stack pointer for this argument.
311    SDValue StackPtr = DAG.getRegister(SP::O6, MVT::i32);
312    // FIXME: VERIFY THAT 68 IS RIGHT.
313    SDValue PtrOff = DAG.getIntPtrConstant(VA.getLocMemOffset()+68);
314    PtrOff = DAG.getNode(ISD::ADD, MVT::i32, StackPtr, PtrOff);
315    MemOpChains.push_back(DAG.getStore(Chain, Arg, PtrOff, NULL, 0));
316  }
317
318#else
319  static const unsigned ArgRegs[] = {
320    SP::I0, SP::I1, SP::I2, SP::I3, SP::I4, SP::I5
321  };
322  unsigned ArgOffset = 68;
323
324  for (unsigned i = 0, e = TheCall->getNumArgs(); i != e; ++i) {
325    SDValue Val = TheCall->getArg(i);
326    MVT ObjectVT = Val.getValueType();
327    SDValue ValToStore(0, 0);
328    unsigned ObjSize;
329    switch (ObjectVT.getSimpleVT()) {
330    default: assert(0 && "Unhandled argument type!");
331    case MVT::i32:
332      ObjSize = 4;
333
334      if (RegsToPass.size() >= 6) {
335        ValToStore = Val;
336      } else {
337        RegsToPass.push_back(std::make_pair(ArgRegs[RegsToPass.size()], Val));
338      }
339      break;
340    case MVT::f32:
341      ObjSize = 4;
342      if (RegsToPass.size() >= 6) {
343        ValToStore = Val;
344      } else {
345        // Convert this to a FP value in an int reg.
346        Val = DAG.getNode(ISD::BIT_CONVERT, MVT::i32, Val);
347        RegsToPass.push_back(std::make_pair(ArgRegs[RegsToPass.size()], Val));
348      }
349      break;
350    case MVT::f64:
351      ObjSize = 8;
352      // Otherwise, convert this to a FP value in int regs.
353      Val = DAG.getNode(ISD::BIT_CONVERT, MVT::i64, Val);
354      // FALL THROUGH
355    case MVT::i64:
356      ObjSize = 8;
357      if (RegsToPass.size() >= 6) {
358        ValToStore = Val;    // Whole thing is passed in memory.
359        break;
360      }
361
362      // Split the value into top and bottom part.  Top part goes in a reg.
363      SDValue Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, MVT::i32, Val,
364                                 DAG.getConstant(1, MVT::i32));
365      SDValue Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, MVT::i32, Val,
366                                 DAG.getConstant(0, MVT::i32));
367      RegsToPass.push_back(std::make_pair(ArgRegs[RegsToPass.size()], Hi));
368
369      if (RegsToPass.size() >= 6) {
370        ValToStore = Lo;
371        ArgOffset += 4;
372        ObjSize = 4;
373      } else {
374        RegsToPass.push_back(std::make_pair(ArgRegs[RegsToPass.size()], Lo));
375      }
376      break;
377    }
378
379    if (ValToStore.getNode()) {
380      SDValue StackPtr = DAG.getRegister(SP::O6, MVT::i32);
381      SDValue PtrOff = DAG.getConstant(ArgOffset, MVT::i32);
382      PtrOff = DAG.getNode(ISD::ADD, MVT::i32, StackPtr, PtrOff);
383      MemOpChains.push_back(DAG.getStore(Chain, ValToStore, PtrOff, NULL, 0));
384    }
385    ArgOffset += ObjSize;
386  }
387#endif
388
389  // Emit all stores, make sure the occur before any copies into physregs.
390  if (!MemOpChains.empty())
391    Chain = DAG.getNode(ISD::TokenFactor, MVT::Other,
392                        &MemOpChains[0], MemOpChains.size());
393
394  // Build a sequence of copy-to-reg nodes chained together with token
395  // chain and flag operands which copy the outgoing args into registers.
396  // The InFlag in necessary since all emited instructions must be
397  // stuck together.
398  SDValue InFlag;
399  for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i) {
400    unsigned Reg = RegsToPass[i].first;
401    // Remap I0->I7 -> O0->O7.
402    if (Reg >= SP::I0 && Reg <= SP::I7)
403      Reg = Reg-SP::I0+SP::O0;
404
405    Chain = DAG.getCopyToReg(Chain, Reg, RegsToPass[i].second, InFlag);
406    InFlag = Chain.getValue(1);
407  }
408
409  // If the callee is a GlobalAddress node (quite common, every direct call is)
410  // turn it into a TargetGlobalAddress node so that legalize doesn't hack it.
411  // Likewise ExternalSymbol -> TargetExternalSymbol.
412  if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee))
413    Callee = DAG.getTargetGlobalAddress(G->getGlobal(), MVT::i32);
414  else if (ExternalSymbolSDNode *E = dyn_cast<ExternalSymbolSDNode>(Callee))
415    Callee = DAG.getTargetExternalSymbol(E->getSymbol(), MVT::i32);
416
417  std::vector<MVT> NodeTys;
418  NodeTys.push_back(MVT::Other);   // Returns a chain
419  NodeTys.push_back(MVT::Flag);    // Returns a flag for retval copy to use.
420  SDValue Ops[] = { Chain, Callee, InFlag };
421  Chain = DAG.getNode(SPISD::CALL, NodeTys, Ops, InFlag.getNode() ? 3 : 2);
422  InFlag = Chain.getValue(1);
423
424  Chain = DAG.getCALLSEQ_END(Chain, DAG.getIntPtrConstant(ArgsSize, true),
425                             DAG.getIntPtrConstant(0, true), InFlag);
426  InFlag = Chain.getValue(1);
427
428  // Assign locations to each value returned by this call.
429  SmallVector<CCValAssign, 16> RVLocs;
430  CCState RVInfo(CallingConv, isVarArg, DAG.getTarget(), RVLocs);
431
432  RVInfo.AnalyzeCallResult(TheCall, RetCC_Sparc32);
433  SmallVector<SDValue, 8> ResultVals;
434
435  // Copy all of the result registers out of their specified physreg.
436  for (unsigned i = 0; i != RVLocs.size(); ++i) {
437    unsigned Reg = RVLocs[i].getLocReg();
438
439    // Remap I0->I7 -> O0->O7.
440    if (Reg >= SP::I0 && Reg <= SP::I7)
441      Reg = Reg-SP::I0+SP::O0;
442
443    Chain = DAG.getCopyFromReg(Chain, Reg,
444                               RVLocs[i].getValVT(), InFlag).getValue(1);
445    InFlag = Chain.getValue(2);
446    ResultVals.push_back(Chain.getValue(0));
447  }
448
449  ResultVals.push_back(Chain);
450
451  // Merge everything together with a MERGE_VALUES node.
452  return DAG.getMergeValues(TheCall->getVTList(), &ResultVals[0],
453                            ResultVals.size());
454}
455
456
457
458//===----------------------------------------------------------------------===//
459// TargetLowering Implementation
460//===----------------------------------------------------------------------===//
461
462/// IntCondCCodeToICC - Convert a DAG integer condition code to a SPARC ICC
463/// condition.
464static SPCC::CondCodes IntCondCCodeToICC(ISD::CondCode CC) {
465  switch (CC) {
466  default: assert(0 && "Unknown integer condition code!");
467  case ISD::SETEQ:  return SPCC::ICC_E;
468  case ISD::SETNE:  return SPCC::ICC_NE;
469  case ISD::SETLT:  return SPCC::ICC_L;
470  case ISD::SETGT:  return SPCC::ICC_G;
471  case ISD::SETLE:  return SPCC::ICC_LE;
472  case ISD::SETGE:  return SPCC::ICC_GE;
473  case ISD::SETULT: return SPCC::ICC_CS;
474  case ISD::SETULE: return SPCC::ICC_LEU;
475  case ISD::SETUGT: return SPCC::ICC_GU;
476  case ISD::SETUGE: return SPCC::ICC_CC;
477  }
478}
479
480/// FPCondCCodeToFCC - Convert a DAG floatingp oint condition code to a SPARC
481/// FCC condition.
482static SPCC::CondCodes FPCondCCodeToFCC(ISD::CondCode CC) {
483  switch (CC) {
484  default: assert(0 && "Unknown fp condition code!");
485  case ISD::SETEQ:
486  case ISD::SETOEQ: return SPCC::FCC_E;
487  case ISD::SETNE:
488  case ISD::SETUNE: return SPCC::FCC_NE;
489  case ISD::SETLT:
490  case ISD::SETOLT: return SPCC::FCC_L;
491  case ISD::SETGT:
492  case ISD::SETOGT: return SPCC::FCC_G;
493  case ISD::SETLE:
494  case ISD::SETOLE: return SPCC::FCC_LE;
495  case ISD::SETGE:
496  case ISD::SETOGE: return SPCC::FCC_GE;
497  case ISD::SETULT: return SPCC::FCC_UL;
498  case ISD::SETULE: return SPCC::FCC_ULE;
499  case ISD::SETUGT: return SPCC::FCC_UG;
500  case ISD::SETUGE: return SPCC::FCC_UGE;
501  case ISD::SETUO:  return SPCC::FCC_U;
502  case ISD::SETO:   return SPCC::FCC_O;
503  case ISD::SETONE: return SPCC::FCC_LG;
504  case ISD::SETUEQ: return SPCC::FCC_UE;
505  }
506}
507
508
509SparcTargetLowering::SparcTargetLowering(TargetMachine &TM)
510  : TargetLowering(TM) {
511
512  // Set up the register classes.
513  addRegisterClass(MVT::i32, SP::IntRegsRegisterClass);
514  addRegisterClass(MVT::f32, SP::FPRegsRegisterClass);
515  addRegisterClass(MVT::f64, SP::DFPRegsRegisterClass);
516
517  // Turn FP extload into load/fextend
518  setLoadExtAction(ISD::EXTLOAD, MVT::f32, Expand);
519  // Sparc doesn't have i1 sign extending load
520  setLoadExtAction(ISD::SEXTLOAD, MVT::i1, Promote);
521  // Turn FP truncstore into trunc + store.
522  setTruncStoreAction(MVT::f64, MVT::f32, Expand);
523
524  // Custom legalize GlobalAddress nodes into LO/HI parts.
525  setOperationAction(ISD::GlobalAddress, MVT::i32, Custom);
526  setOperationAction(ISD::GlobalTLSAddress, MVT::i32, Custom);
527  setOperationAction(ISD::ConstantPool , MVT::i32, Custom);
528
529  // Sparc doesn't have sext_inreg, replace them with shl/sra
530  setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i16, Expand);
531  setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i8 , Expand);
532  setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i1 , Expand);
533
534  // Sparc has no REM or DIVREM operations.
535  setOperationAction(ISD::UREM, MVT::i32, Expand);
536  setOperationAction(ISD::SREM, MVT::i32, Expand);
537  setOperationAction(ISD::SDIVREM, MVT::i32, Expand);
538  setOperationAction(ISD::UDIVREM, MVT::i32, Expand);
539
540  // Custom expand fp<->sint
541  setOperationAction(ISD::FP_TO_SINT, MVT::i32, Custom);
542  setOperationAction(ISD::SINT_TO_FP, MVT::i32, Custom);
543
544  // Expand fp<->uint
545  setOperationAction(ISD::FP_TO_UINT, MVT::i32, Expand);
546  setOperationAction(ISD::UINT_TO_FP, MVT::i32, Expand);
547
548  setOperationAction(ISD::BIT_CONVERT, MVT::f32, Expand);
549  setOperationAction(ISD::BIT_CONVERT, MVT::i32, Expand);
550
551  // Sparc has no select or setcc: expand to SELECT_CC.
552  setOperationAction(ISD::SELECT, MVT::i32, Expand);
553  setOperationAction(ISD::SELECT, MVT::f32, Expand);
554  setOperationAction(ISD::SELECT, MVT::f64, Expand);
555  setOperationAction(ISD::SETCC, MVT::i32, Expand);
556  setOperationAction(ISD::SETCC, MVT::f32, Expand);
557  setOperationAction(ISD::SETCC, MVT::f64, Expand);
558
559  // Sparc doesn't have BRCOND either, it has BR_CC.
560  setOperationAction(ISD::BRCOND, MVT::Other, Expand);
561  setOperationAction(ISD::BRIND, MVT::Other, Expand);
562  setOperationAction(ISD::BR_JT, MVT::Other, Expand);
563  setOperationAction(ISD::BR_CC, MVT::i32, Custom);
564  setOperationAction(ISD::BR_CC, MVT::f32, Custom);
565  setOperationAction(ISD::BR_CC, MVT::f64, Custom);
566
567  setOperationAction(ISD::SELECT_CC, MVT::i32, Custom);
568  setOperationAction(ISD::SELECT_CC, MVT::f32, Custom);
569  setOperationAction(ISD::SELECT_CC, MVT::f64, Custom);
570
571  // SPARC has no intrinsics for these particular operations.
572  setOperationAction(ISD::MEMBARRIER, MVT::Other, Expand);
573
574  setOperationAction(ISD::FSIN , MVT::f64, Expand);
575  setOperationAction(ISD::FCOS , MVT::f64, Expand);
576  setOperationAction(ISD::FREM , MVT::f64, Expand);
577  setOperationAction(ISD::FSIN , MVT::f32, Expand);
578  setOperationAction(ISD::FCOS , MVT::f32, Expand);
579  setOperationAction(ISD::FREM , MVT::f32, Expand);
580  setOperationAction(ISD::CTPOP, MVT::i32, Expand);
581  setOperationAction(ISD::CTTZ , MVT::i32, Expand);
582  setOperationAction(ISD::CTLZ , MVT::i32, Expand);
583  setOperationAction(ISD::ROTL , MVT::i32, Expand);
584  setOperationAction(ISD::ROTR , MVT::i32, Expand);
585  setOperationAction(ISD::BSWAP, MVT::i32, Expand);
586  setOperationAction(ISD::FCOPYSIGN, MVT::f64, Expand);
587  setOperationAction(ISD::FCOPYSIGN, MVT::f32, Expand);
588  setOperationAction(ISD::FPOW , MVT::f64, Expand);
589  setOperationAction(ISD::FPOW , MVT::f32, Expand);
590
591  setOperationAction(ISD::SHL_PARTS, MVT::i32, Expand);
592  setOperationAction(ISD::SRA_PARTS, MVT::i32, Expand);
593  setOperationAction(ISD::SRL_PARTS, MVT::i32, Expand);
594
595  // FIXME: Sparc provides these multiplies, but we don't have them yet.
596  setOperationAction(ISD::UMUL_LOHI, MVT::i32, Expand);
597  setOperationAction(ISD::SMUL_LOHI, MVT::i32, Expand);
598
599  // We don't have line number support yet.
600  setOperationAction(ISD::DBG_STOPPOINT, MVT::Other, Expand);
601  setOperationAction(ISD::DEBUG_LOC, MVT::Other, Expand);
602  setOperationAction(ISD::DBG_LABEL, MVT::Other, Expand);
603  setOperationAction(ISD::EH_LABEL, MVT::Other, Expand);
604
605  // RET must be custom lowered, to meet ABI requirements
606  setOperationAction(ISD::RET               , MVT::Other, Custom);
607
608  // VASTART needs to be custom lowered to use the VarArgsFrameIndex.
609  setOperationAction(ISD::VASTART           , MVT::Other, Custom);
610  // VAARG needs to be lowered to not do unaligned accesses for doubles.
611  setOperationAction(ISD::VAARG             , MVT::Other, Custom);
612
613  // Use the default implementation.
614  setOperationAction(ISD::VACOPY            , MVT::Other, Expand);
615  setOperationAction(ISD::VAEND             , MVT::Other, Expand);
616  setOperationAction(ISD::STACKSAVE         , MVT::Other, Expand);
617  setOperationAction(ISD::STACKRESTORE      , MVT::Other, Expand);
618  setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32  , Custom);
619
620  // No debug info support yet.
621  setOperationAction(ISD::DBG_STOPPOINT, MVT::Other, Expand);
622  setOperationAction(ISD::DBG_LABEL, MVT::Other, Expand);
623  setOperationAction(ISD::EH_LABEL, MVT::Other, Expand);
624  setOperationAction(ISD::DECLARE, MVT::Other, Expand);
625
626  setStackPointerRegisterToSaveRestore(SP::O6);
627
628  if (TM.getSubtarget<SparcSubtarget>().isV9())
629    setOperationAction(ISD::CTPOP, MVT::i32, Legal);
630
631  computeRegisterProperties();
632}
633
634const char *SparcTargetLowering::getTargetNodeName(unsigned Opcode) const {
635  switch (Opcode) {
636  default: return 0;
637  case SPISD::CMPICC:     return "SPISD::CMPICC";
638  case SPISD::CMPFCC:     return "SPISD::CMPFCC";
639  case SPISD::BRICC:      return "SPISD::BRICC";
640  case SPISD::BRFCC:      return "SPISD::BRFCC";
641  case SPISD::SELECT_ICC: return "SPISD::SELECT_ICC";
642  case SPISD::SELECT_FCC: return "SPISD::SELECT_FCC";
643  case SPISD::Hi:         return "SPISD::Hi";
644  case SPISD::Lo:         return "SPISD::Lo";
645  case SPISD::FTOI:       return "SPISD::FTOI";
646  case SPISD::ITOF:       return "SPISD::ITOF";
647  case SPISD::CALL:       return "SPISD::CALL";
648  case SPISD::RET_FLAG:   return "SPISD::RET_FLAG";
649  }
650}
651
652/// isMaskedValueZeroForTargetNode - Return true if 'Op & Mask' is known to
653/// be zero. Op is expected to be a target specific node. Used by DAG
654/// combiner.
655void SparcTargetLowering::computeMaskedBitsForTargetNode(const SDValue Op,
656                                                         const APInt &Mask,
657                                                         APInt &KnownZero,
658                                                         APInt &KnownOne,
659                                                         const SelectionDAG &DAG,
660                                                         unsigned Depth) const {
661  APInt KnownZero2, KnownOne2;
662  KnownZero = KnownOne = APInt(Mask.getBitWidth(), 0);   // Don't know anything.
663
664  switch (Op.getOpcode()) {
665  default: break;
666  case SPISD::SELECT_ICC:
667  case SPISD::SELECT_FCC:
668    DAG.ComputeMaskedBits(Op.getOperand(1), Mask, KnownZero, KnownOne,
669                          Depth+1);
670    DAG.ComputeMaskedBits(Op.getOperand(0), Mask, KnownZero2, KnownOne2,
671                          Depth+1);
672    assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
673    assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?");
674
675    // Only known if known in both the LHS and RHS.
676    KnownOne &= KnownOne2;
677    KnownZero &= KnownZero2;
678    break;
679  }
680}
681
682// Look at LHS/RHS/CC and see if they are a lowered setcc instruction.  If so
683// set LHS/RHS and SPCC to the LHS/RHS of the setcc and SPCC to the condition.
684static void LookThroughSetCC(SDValue &LHS, SDValue &RHS,
685                             ISD::CondCode CC, unsigned &SPCC) {
686  if (isa<ConstantSDNode>(RHS) &&
687      cast<ConstantSDNode>(RHS)->getZExtValue() == 0 &&
688      CC == ISD::SETNE &&
689      ((LHS.getOpcode() == SPISD::SELECT_ICC &&
690        LHS.getOperand(3).getOpcode() == SPISD::CMPICC) ||
691       (LHS.getOpcode() == SPISD::SELECT_FCC &&
692        LHS.getOperand(3).getOpcode() == SPISD::CMPFCC)) &&
693      isa<ConstantSDNode>(LHS.getOperand(0)) &&
694      isa<ConstantSDNode>(LHS.getOperand(1)) &&
695      cast<ConstantSDNode>(LHS.getOperand(0))->getZExtValue() == 1 &&
696      cast<ConstantSDNode>(LHS.getOperand(1))->getZExtValue() == 0) {
697    SDValue CMPCC = LHS.getOperand(3);
698    SPCC = cast<ConstantSDNode>(LHS.getOperand(2))->getZExtValue();
699    LHS = CMPCC.getOperand(0);
700    RHS = CMPCC.getOperand(1);
701  }
702}
703
704static SDValue LowerGLOBALADDRESS(SDValue Op, SelectionDAG &DAG) {
705  GlobalValue *GV = cast<GlobalAddressSDNode>(Op)->getGlobal();
706  SDValue GA = DAG.getTargetGlobalAddress(GV, MVT::i32);
707  SDValue Hi = DAG.getNode(SPISD::Hi, MVT::i32, GA);
708  SDValue Lo = DAG.getNode(SPISD::Lo, MVT::i32, GA);
709  return DAG.getNode(ISD::ADD, MVT::i32, Lo, Hi);
710}
711
712static SDValue LowerCONSTANTPOOL(SDValue Op, SelectionDAG &DAG) {
713  ConstantPoolSDNode *N = cast<ConstantPoolSDNode>(Op);
714  Constant *C = N->getConstVal();
715  SDValue CP = DAG.getTargetConstantPool(C, MVT::i32, N->getAlignment());
716  SDValue Hi = DAG.getNode(SPISD::Hi, MVT::i32, CP);
717  SDValue Lo = DAG.getNode(SPISD::Lo, MVT::i32, CP);
718  return DAG.getNode(ISD::ADD, MVT::i32, Lo, Hi);
719}
720
721static SDValue LowerFP_TO_SINT(SDValue Op, SelectionDAG &DAG) {
722  // Convert the fp value to integer in an FP register.
723  assert(Op.getValueType() == MVT::i32);
724  Op = DAG.getNode(SPISD::FTOI, MVT::f32, Op.getOperand(0));
725  return DAG.getNode(ISD::BIT_CONVERT, MVT::i32, Op);
726}
727
728static SDValue LowerSINT_TO_FP(SDValue Op, SelectionDAG &DAG) {
729  assert(Op.getOperand(0).getValueType() == MVT::i32);
730  SDValue Tmp = DAG.getNode(ISD::BIT_CONVERT, MVT::f32, Op.getOperand(0));
731  // Convert the int value to FP in an FP register.
732  return DAG.getNode(SPISD::ITOF, Op.getValueType(), Tmp);
733}
734
735static SDValue LowerBR_CC(SDValue Op, SelectionDAG &DAG) {
736  SDValue Chain = Op.getOperand(0);
737  ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(1))->get();
738  SDValue LHS = Op.getOperand(2);
739  SDValue RHS = Op.getOperand(3);
740  SDValue Dest = Op.getOperand(4);
741  unsigned Opc, SPCC = ~0U;
742
743  // If this is a br_cc of a "setcc", and if the setcc got lowered into
744  // an CMP[IF]CC/SELECT_[IF]CC pair, find the original compared values.
745  LookThroughSetCC(LHS, RHS, CC, SPCC);
746
747  // Get the condition flag.
748  SDValue CompareFlag;
749  if (LHS.getValueType() == MVT::i32) {
750    std::vector<MVT> VTs;
751    VTs.push_back(MVT::i32);
752    VTs.push_back(MVT::Flag);
753    SDValue Ops[2] = { LHS, RHS };
754    CompareFlag = DAG.getNode(SPISD::CMPICC, VTs, Ops, 2).getValue(1);
755    if (SPCC == ~0U) SPCC = IntCondCCodeToICC(CC);
756    Opc = SPISD::BRICC;
757  } else {
758    CompareFlag = DAG.getNode(SPISD::CMPFCC, MVT::Flag, LHS, RHS);
759    if (SPCC == ~0U) SPCC = FPCondCCodeToFCC(CC);
760    Opc = SPISD::BRFCC;
761  }
762  return DAG.getNode(Opc, MVT::Other, Chain, Dest,
763                     DAG.getConstant(SPCC, MVT::i32), CompareFlag);
764}
765
766static SDValue LowerSELECT_CC(SDValue Op, SelectionDAG &DAG) {
767  SDValue LHS = Op.getOperand(0);
768  SDValue RHS = Op.getOperand(1);
769  ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(4))->get();
770  SDValue TrueVal = Op.getOperand(2);
771  SDValue FalseVal = Op.getOperand(3);
772  unsigned Opc, SPCC = ~0U;
773
774  // If this is a select_cc of a "setcc", and if the setcc got lowered into
775  // an CMP[IF]CC/SELECT_[IF]CC pair, find the original compared values.
776  LookThroughSetCC(LHS, RHS, CC, SPCC);
777
778  SDValue CompareFlag;
779  if (LHS.getValueType() == MVT::i32) {
780    std::vector<MVT> VTs;
781    VTs.push_back(LHS.getValueType());   // subcc returns a value
782    VTs.push_back(MVT::Flag);
783    SDValue Ops[2] = { LHS, RHS };
784    CompareFlag = DAG.getNode(SPISD::CMPICC, VTs, Ops, 2).getValue(1);
785    Opc = SPISD::SELECT_ICC;
786    if (SPCC == ~0U) SPCC = IntCondCCodeToICC(CC);
787  } else {
788    CompareFlag = DAG.getNode(SPISD::CMPFCC, MVT::Flag, LHS, RHS);
789    Opc = SPISD::SELECT_FCC;
790    if (SPCC == ~0U) SPCC = FPCondCCodeToFCC(CC);
791  }
792  return DAG.getNode(Opc, TrueVal.getValueType(), TrueVal, FalseVal,
793                     DAG.getConstant(SPCC, MVT::i32), CompareFlag);
794}
795
796static SDValue LowerVASTART(SDValue Op, SelectionDAG &DAG,
797                              SparcTargetLowering &TLI) {
798  // vastart just stores the address of the VarArgsFrameIndex slot into the
799  // memory location argument.
800  SDValue Offset = DAG.getNode(ISD::ADD, MVT::i32,
801                                 DAG.getRegister(SP::I6, MVT::i32),
802                                 DAG.getConstant(TLI.getVarArgsFrameOffset(),
803                                                 MVT::i32));
804  const Value *SV = cast<SrcValueSDNode>(Op.getOperand(2))->getValue();
805  return DAG.getStore(Op.getOperand(0), Offset, Op.getOperand(1), SV, 0);
806}
807
808static SDValue LowerVAARG(SDValue Op, SelectionDAG &DAG) {
809  SDNode *Node = Op.getNode();
810  MVT VT = Node->getValueType(0);
811  SDValue InChain = Node->getOperand(0);
812  SDValue VAListPtr = Node->getOperand(1);
813  const Value *SV = cast<SrcValueSDNode>(Node->getOperand(2))->getValue();
814  SDValue VAList = DAG.getLoad(MVT::i32, InChain, VAListPtr, SV, 0);
815  // Increment the pointer, VAList, to the next vaarg
816  SDValue NextPtr = DAG.getNode(ISD::ADD, MVT::i32, VAList,
817                                  DAG.getConstant(VT.getSizeInBits()/8,
818                                                  MVT::i32));
819  // Store the incremented VAList to the legalized pointer
820  InChain = DAG.getStore(VAList.getValue(1), NextPtr,
821                         VAListPtr, SV, 0);
822  // Load the actual argument out of the pointer VAList, unless this is an
823  // f64 load.
824  if (VT != MVT::f64)
825    return DAG.getLoad(VT, InChain, VAList, NULL, 0);
826
827  // Otherwise, load it as i64, then do a bitconvert.
828  SDValue V = DAG.getLoad(MVT::i64, InChain, VAList, NULL, 0);
829
830  // Bit-Convert the value to f64.
831  SDValue Ops[2] = {
832    DAG.getNode(ISD::BIT_CONVERT, MVT::f64, V),
833    V.getValue(1)
834  };
835  return DAG.getMergeValues(Ops, 2);
836}
837
838static SDValue LowerDYNAMIC_STACKALLOC(SDValue Op, SelectionDAG &DAG) {
839  SDValue Chain = Op.getOperand(0);  // Legalize the chain.
840  SDValue Size  = Op.getOperand(1);  // Legalize the size.
841
842  unsigned SPReg = SP::O6;
843  SDValue SP = DAG.getCopyFromReg(Chain, SPReg, MVT::i32);
844  SDValue NewSP = DAG.getNode(ISD::SUB, MVT::i32, SP, Size);    // Value
845  Chain = DAG.getCopyToReg(SP.getValue(1), SPReg, NewSP);      // Output chain
846
847  // The resultant pointer is actually 16 words from the bottom of the stack,
848  // to provide a register spill area.
849  SDValue NewVal = DAG.getNode(ISD::ADD, MVT::i32, NewSP,
850                                 DAG.getConstant(96, MVT::i32));
851  SDValue Ops[2] = { NewVal, Chain };
852  return DAG.getMergeValues(Ops, 2);
853}
854
855
856SDValue SparcTargetLowering::
857LowerOperation(SDValue Op, SelectionDAG &DAG) {
858  switch (Op.getOpcode()) {
859  default: assert(0 && "Should not custom lower this!");
860  // Frame & Return address.  Currently unimplemented
861  case ISD::RETURNADDR: return SDValue();
862  case ISD::FRAMEADDR:  return SDValue();
863  case ISD::GlobalTLSAddress:
864    assert(0 && "TLS not implemented for Sparc.");
865  case ISD::GlobalAddress:      return LowerGLOBALADDRESS(Op, DAG);
866  case ISD::ConstantPool:       return LowerCONSTANTPOOL(Op, DAG);
867  case ISD::FP_TO_SINT:         return LowerFP_TO_SINT(Op, DAG);
868  case ISD::SINT_TO_FP:         return LowerSINT_TO_FP(Op, DAG);
869  case ISD::BR_CC:              return LowerBR_CC(Op, DAG);
870  case ISD::SELECT_CC:          return LowerSELECT_CC(Op, DAG);
871  case ISD::VASTART:            return LowerVASTART(Op, DAG, *this);
872  case ISD::VAARG:              return LowerVAARG(Op, DAG);
873  case ISD::DYNAMIC_STACKALLOC: return LowerDYNAMIC_STACKALLOC(Op, DAG);
874  case ISD::CALL:               return LowerCALL(Op, DAG);
875  case ISD::RET:                return LowerRET(Op, DAG);
876  }
877}
878
879MachineBasicBlock *
880SparcTargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
881                                                 MachineBasicBlock *BB) {
882  const TargetInstrInfo &TII = *getTargetMachine().getInstrInfo();
883  unsigned BROpcode;
884  unsigned CC;
885  // Figure out the conditional branch opcode to use for this select_cc.
886  switch (MI->getOpcode()) {
887  default: assert(0 && "Unknown SELECT_CC!");
888  case SP::SELECT_CC_Int_ICC:
889  case SP::SELECT_CC_FP_ICC:
890  case SP::SELECT_CC_DFP_ICC:
891    BROpcode = SP::BCOND;
892    break;
893  case SP::SELECT_CC_Int_FCC:
894  case SP::SELECT_CC_FP_FCC:
895  case SP::SELECT_CC_DFP_FCC:
896    BROpcode = SP::FBCOND;
897    break;
898  }
899
900  CC = (SPCC::CondCodes)MI->getOperand(3).getImm();
901
902  // To "insert" a SELECT_CC instruction, we actually have to insert the diamond
903  // control-flow pattern.  The incoming instruction knows the destination vreg
904  // to set, the condition code register to branch on, the true/false values to
905  // select between, and a branch opcode to use.
906  const BasicBlock *LLVM_BB = BB->getBasicBlock();
907  MachineFunction::iterator It = BB;
908  ++It;
909
910  //  thisMBB:
911  //  ...
912  //   TrueVal = ...
913  //   [f]bCC copy1MBB
914  //   fallthrough --> copy0MBB
915  MachineBasicBlock *thisMBB = BB;
916  MachineFunction *F = BB->getParent();
917  MachineBasicBlock *copy0MBB = F->CreateMachineBasicBlock(LLVM_BB);
918  MachineBasicBlock *sinkMBB = F->CreateMachineBasicBlock(LLVM_BB);
919  BuildMI(BB, TII.get(BROpcode)).addMBB(sinkMBB).addImm(CC);
920  F->insert(It, copy0MBB);
921  F->insert(It, sinkMBB);
922  // Update machine-CFG edges by transferring all successors of the current
923  // block to the new block which will contain the Phi node for the select.
924  sinkMBB->transferSuccessors(BB);
925  // Next, add the true and fallthrough blocks as its successors.
926  BB->addSuccessor(copy0MBB);
927  BB->addSuccessor(sinkMBB);
928
929  //  copy0MBB:
930  //   %FalseValue = ...
931  //   # fallthrough to sinkMBB
932  BB = copy0MBB;
933
934  // Update machine-CFG edges
935  BB->addSuccessor(sinkMBB);
936
937  //  sinkMBB:
938  //   %Result = phi [ %FalseValue, copy0MBB ], [ %TrueValue, thisMBB ]
939  //  ...
940  BB = sinkMBB;
941  BuildMI(BB, TII.get(SP::PHI), MI->getOperand(0).getReg())
942    .addReg(MI->getOperand(2).getReg()).addMBB(copy0MBB)
943    .addReg(MI->getOperand(1).getReg()).addMBB(thisMBB);
944
945  F->DeleteMachineInstr(MI);   // The pseudo instruction is gone now.
946  return BB;
947}
948
949//===----------------------------------------------------------------------===//
950//                         Sparc Inline Assembly Support
951//===----------------------------------------------------------------------===//
952
953/// getConstraintType - Given a constraint letter, return the type of
954/// constraint it is for this target.
955SparcTargetLowering::ConstraintType
956SparcTargetLowering::getConstraintType(const std::string &Constraint) const {
957  if (Constraint.size() == 1) {
958    switch (Constraint[0]) {
959    default:  break;
960    case 'r': return C_RegisterClass;
961    }
962  }
963
964  return TargetLowering::getConstraintType(Constraint);
965}
966
967std::pair<unsigned, const TargetRegisterClass*>
968SparcTargetLowering::getRegForInlineAsmConstraint(const std::string &Constraint,
969                                                  MVT VT) const {
970  if (Constraint.size() == 1) {
971    switch (Constraint[0]) {
972    case 'r':
973      return std::make_pair(0U, SP::IntRegsRegisterClass);
974    }
975  }
976
977  return TargetLowering::getRegForInlineAsmConstraint(Constraint, VT);
978}
979
980std::vector<unsigned> SparcTargetLowering::
981getRegClassForInlineAsmConstraint(const std::string &Constraint,
982                                  MVT VT) const {
983  if (Constraint.size() != 1)
984    return std::vector<unsigned>();
985
986  switch (Constraint[0]) {
987  default: break;
988  case 'r':
989    return make_vector<unsigned>(SP::L0, SP::L1, SP::L2, SP::L3,
990                                 SP::L4, SP::L5, SP::L6, SP::L7,
991                                 SP::I0, SP::I1, SP::I2, SP::I3,
992                                 SP::I4, SP::I5,
993                                 SP::O0, SP::O1, SP::O2, SP::O3,
994                                 SP::O4, SP::O5, SP::O7, 0);
995  }
996
997  return std::vector<unsigned>();
998}
999