SparcISelLowering.cpp revision 98ca4f2a325f72374a477f9deba7d09e8999c29b
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/Target/TargetLoweringObjectFile.h"
25#include "llvm/ADT/VectorExtras.h"
26#include "llvm/Support/ErrorHandling.h"
27using namespace llvm;
28
29
30//===----------------------------------------------------------------------===//
31// Calling Convention Implementation
32//===----------------------------------------------------------------------===//
33
34#include "SparcGenCallingConv.inc"
35
36SDValue
37SparcTargetLowering::LowerReturn(SDValue Chain,
38                                 unsigned CallConv, bool isVarArg,
39                                 const SmallVectorImpl<ISD::OutputArg> &Outs,
40                                 DebugLoc dl, SelectionDAG &DAG) {
41
42  // CCValAssign - represent the assignment of the return value to locations.
43  SmallVector<CCValAssign, 16> RVLocs;
44
45  // CCState - Info about the registers and stack slot.
46  CCState CCInfo(CallConv, isVarArg, DAG.getTarget(),
47                 RVLocs, *DAG.getContext());
48
49  // Analize return values.
50  CCInfo.AnalyzeReturn(Outs, RetCC_Sparc32);
51
52  // If this is the first return lowered for this function, add the regs to the
53  // liveout set for the function.
54  if (DAG.getMachineFunction().getRegInfo().liveout_empty()) {
55    for (unsigned i = 0; i != RVLocs.size(); ++i)
56      if (RVLocs[i].isRegLoc())
57        DAG.getMachineFunction().getRegInfo().addLiveOut(RVLocs[i].getLocReg());
58  }
59
60  SDValue Flag;
61
62  // Copy the result values into the output registers.
63  for (unsigned i = 0; i != RVLocs.size(); ++i) {
64    CCValAssign &VA = RVLocs[i];
65    assert(VA.isRegLoc() && "Can only return in registers!");
66
67    Chain = DAG.getCopyToReg(Chain, dl, VA.getLocReg(),
68                             Outs[i].Val, Flag);
69
70    // Guarantee that all emitted copies are stuck together with flags.
71    Flag = Chain.getValue(1);
72  }
73
74  if (Flag.getNode())
75    return DAG.getNode(SPISD::RET_FLAG, dl, MVT::Other, Chain, Flag);
76  return DAG.getNode(SPISD::RET_FLAG, dl, MVT::Other, Chain);
77}
78
79/// LowerFormalArguments - V8 uses a very simple ABI, where all values are
80/// passed in either one or two GPRs, including FP values.  TODO: we should
81/// pass FP values in FP registers for fastcc functions.
82SDValue
83SparcTargetLowering::LowerFormalArguments(SDValue Chain,
84                                          unsigned CallConv, bool isVarArg,
85                                          const SmallVectorImpl<ISD::InputArg>
86                                            &Ins,
87                                          DebugLoc dl, SelectionDAG &DAG,
88                                          SmallVectorImpl<SDValue> &InVals) {
89
90  MachineFunction &MF = DAG.getMachineFunction();
91  MachineRegisterInfo &RegInfo = MF.getRegInfo();
92
93  // Assign locations to all of the incoming arguments.
94  SmallVector<CCValAssign, 16> ArgLocs;
95  CCState CCInfo(CallConv, isVarArg, getTargetMachine(),
96                 ArgLocs, *DAG.getContext());
97  CCInfo.AnalyzeFormalArguments(Ins, CC_Sparc32);
98
99  static const unsigned ArgRegs[] = {
100    SP::I0, SP::I1, SP::I2, SP::I3, SP::I4, SP::I5
101  };
102  const unsigned *CurArgReg = ArgRegs, *ArgRegEnd = ArgRegs+6;
103  unsigned ArgOffset = 68;
104
105  for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
106    SDValue ArgValue;
107    CCValAssign &VA = ArgLocs[i];
108    // FIXME: We ignore the register assignments of AnalyzeFormalArguments
109    // because it doesn't know how to split a double into two i32 registers.
110    MVT ObjectVT = VA.getValVT();
111    switch (ObjectVT.getSimpleVT()) {
112    default: llvm_unreachable("Unhandled argument type!");
113    case MVT::i1:
114    case MVT::i8:
115    case MVT::i16:
116    case MVT::i32:
117      if (!Ins[i].Used) {                  // Argument is dead.
118        if (CurArgReg < ArgRegEnd) ++CurArgReg;
119        InVals.push_back(DAG.getUNDEF(ObjectVT));
120      } else if (CurArgReg < ArgRegEnd) {  // Lives in an incoming GPR
121        unsigned VReg = RegInfo.createVirtualRegister(&SP::IntRegsRegClass);
122        MF.getRegInfo().addLiveIn(*CurArgReg++, VReg);
123        SDValue Arg = DAG.getCopyFromReg(Chain, dl, VReg, MVT::i32);
124        if (ObjectVT != MVT::i32) {
125          unsigned AssertOp = ISD::AssertSext;
126          Arg = DAG.getNode(AssertOp, dl, MVT::i32, Arg,
127                            DAG.getValueType(ObjectVT));
128          Arg = DAG.getNode(ISD::TRUNCATE, dl, ObjectVT, Arg);
129        }
130        InVals.push_back(Arg);
131      } else {
132        int FrameIdx = MF.getFrameInfo()->CreateFixedObject(4, ArgOffset);
133        SDValue FIPtr = DAG.getFrameIndex(FrameIdx, MVT::i32);
134        SDValue Load;
135        if (ObjectVT == MVT::i32) {
136          Load = DAG.getLoad(MVT::i32, dl, Chain, FIPtr, NULL, 0);
137        } else {
138          ISD::LoadExtType LoadOp = ISD::SEXTLOAD;
139
140          // Sparc is big endian, so add an offset based on the ObjectVT.
141          unsigned Offset = 4-std::max(1U, ObjectVT.getSizeInBits()/8);
142          FIPtr = DAG.getNode(ISD::ADD, dl, MVT::i32, FIPtr,
143                              DAG.getConstant(Offset, MVT::i32));
144          Load = DAG.getExtLoad(LoadOp, dl, MVT::i32, Chain, FIPtr,
145                                NULL, 0, ObjectVT);
146          Load = DAG.getNode(ISD::TRUNCATE, dl, ObjectVT, Load);
147        }
148        InVals.push_back(Load);
149      }
150
151      ArgOffset += 4;
152      break;
153    case MVT::f32:
154      if (!Ins[i].Used) {                  // Argument is dead.
155        if (CurArgReg < ArgRegEnd) ++CurArgReg;
156        InVals.push_back(DAG.getUNDEF(ObjectVT));
157      } else if (CurArgReg < ArgRegEnd) {  // Lives in an incoming GPR
158        // FP value is passed in an integer register.
159        unsigned VReg = RegInfo.createVirtualRegister(&SP::IntRegsRegClass);
160        MF.getRegInfo().addLiveIn(*CurArgReg++, VReg);
161        SDValue Arg = DAG.getCopyFromReg(Chain, dl, VReg, MVT::i32);
162
163        Arg = DAG.getNode(ISD::BIT_CONVERT, dl, MVT::f32, Arg);
164        InVals.push_back(Arg);
165      } else {
166        int FrameIdx = MF.getFrameInfo()->CreateFixedObject(4, ArgOffset);
167        SDValue FIPtr = DAG.getFrameIndex(FrameIdx, MVT::i32);
168        SDValue Load = DAG.getLoad(MVT::f32, dl, Chain, FIPtr, NULL, 0);
169        InVals.push_back(Load);
170      }
171      ArgOffset += 4;
172      break;
173
174    case MVT::i64:
175    case MVT::f64:
176      if (!Ins[i].Used) {                // Argument is dead.
177        if (CurArgReg < ArgRegEnd) ++CurArgReg;
178        if (CurArgReg < ArgRegEnd) ++CurArgReg;
179        InVals.push_back(DAG.getUNDEF(ObjectVT));
180      } else {
181        SDValue HiVal;
182        if (CurArgReg < ArgRegEnd) {  // Lives in an incoming GPR
183          unsigned VRegHi = RegInfo.createVirtualRegister(&SP::IntRegsRegClass);
184          MF.getRegInfo().addLiveIn(*CurArgReg++, VRegHi);
185          HiVal = DAG.getCopyFromReg(Chain, dl, VRegHi, MVT::i32);
186        } else {
187          int FrameIdx = MF.getFrameInfo()->CreateFixedObject(4, ArgOffset);
188          SDValue FIPtr = DAG.getFrameIndex(FrameIdx, MVT::i32);
189          HiVal = DAG.getLoad(MVT::i32, dl, Chain, FIPtr, NULL, 0);
190        }
191
192        SDValue LoVal;
193        if (CurArgReg < ArgRegEnd) {  // Lives in an incoming GPR
194          unsigned VRegLo = RegInfo.createVirtualRegister(&SP::IntRegsRegClass);
195          MF.getRegInfo().addLiveIn(*CurArgReg++, VRegLo);
196          LoVal = DAG.getCopyFromReg(Chain, dl, VRegLo, MVT::i32);
197        } else {
198          int FrameIdx = MF.getFrameInfo()->CreateFixedObject(4, ArgOffset+4);
199          SDValue FIPtr = DAG.getFrameIndex(FrameIdx, MVT::i32);
200          LoVal = DAG.getLoad(MVT::i32, dl, Chain, FIPtr, NULL, 0);
201        }
202
203        // Compose the two halves together into an i64 unit.
204        SDValue WholeValue =
205          DAG.getNode(ISD::BUILD_PAIR, dl, MVT::i64, LoVal, HiVal);
206
207        // If we want a double, do a bit convert.
208        if (ObjectVT == MVT::f64)
209          WholeValue = DAG.getNode(ISD::BIT_CONVERT, dl, MVT::f64, WholeValue);
210
211        InVals.push_back(WholeValue);
212      }
213      ArgOffset += 8;
214      break;
215    }
216  }
217
218  // Store remaining ArgRegs to the stack if this is a varargs function.
219  if (isVarArg) {
220    // Remember the vararg offset for the va_start implementation.
221    VarArgsFrameOffset = ArgOffset;
222
223    std::vector<SDValue> OutChains;
224
225    for (; CurArgReg != ArgRegEnd; ++CurArgReg) {
226      unsigned VReg = RegInfo.createVirtualRegister(&SP::IntRegsRegClass);
227      MF.getRegInfo().addLiveIn(*CurArgReg, VReg);
228      SDValue Arg = DAG.getCopyFromReg(DAG.getRoot(), dl, VReg, MVT::i32);
229
230      int FrameIdx = MF.getFrameInfo()->CreateFixedObject(4, ArgOffset);
231      SDValue FIPtr = DAG.getFrameIndex(FrameIdx, MVT::i32);
232
233      OutChains.push_back(DAG.getStore(DAG.getRoot(), dl, Arg, FIPtr, NULL, 0));
234      ArgOffset += 4;
235    }
236
237    if (!OutChains.empty()) {
238      OutChains.push_back(Chain);
239      Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
240                          &OutChains[0], OutChains.size());
241    }
242  }
243
244  return Chain;
245}
246
247SDValue
248SparcTargetLowering::LowerCall(SDValue Chain, SDValue Callee,
249                               unsigned CallConv, bool isVarArg,
250                               bool isTailCall,
251                               const SmallVectorImpl<ISD::OutputArg> &Outs,
252                               const SmallVectorImpl<ISD::InputArg> &Ins,
253                               DebugLoc dl, SelectionDAG &DAG,
254                               SmallVectorImpl<SDValue> &InVals) {
255
256#if 0
257  // Analyze operands of the call, assigning locations to each operand.
258  SmallVector<CCValAssign, 16> ArgLocs;
259  CCState CCInfo(CallConv, isVarArg, DAG.getTarget(), ArgLocs);
260  CCInfo.AnalyzeCallOperands(Outs, CC_Sparc32);
261
262  // Get the size of the outgoing arguments stack space requirement.
263  unsigned ArgsSize = CCInfo.getNextStackOffset();
264  // FIXME: We can't use this until f64 is known to take two GPRs.
265#else
266  (void)CC_Sparc32;
267
268  // Count the size of the outgoing arguments.
269  unsigned ArgsSize = 0;
270  for (unsigned i = 0, e = Outs.size(); i != e; ++i) {
271    switch (Outs[i].Val.getValueType().getSimpleVT()) {
272      default: llvm_unreachable("Unknown value type!");
273      case MVT::i1:
274      case MVT::i8:
275      case MVT::i16:
276      case MVT::i32:
277      case MVT::f32:
278        ArgsSize += 4;
279        break;
280      case MVT::i64:
281      case MVT::f64:
282        ArgsSize += 8;
283        break;
284    }
285  }
286  if (ArgsSize > 4*6)
287    ArgsSize -= 4*6;    // Space for first 6 arguments is prereserved.
288  else
289    ArgsSize = 0;
290#endif
291
292  // Keep stack frames 8-byte aligned.
293  ArgsSize = (ArgsSize+7) & ~7;
294
295  Chain = DAG.getCALLSEQ_START(Chain, DAG.getIntPtrConstant(ArgsSize, true));
296
297  SmallVector<std::pair<unsigned, SDValue>, 8> RegsToPass;
298  SmallVector<SDValue, 8> MemOpChains;
299
300#if 0
301  // Walk the register/memloc assignments, inserting copies/loads.
302  for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
303    CCValAssign &VA = ArgLocs[i];
304    SDValue Arg = Outs[i].Val;
305
306    // Promote the value if needed.
307    switch (VA.getLocInfo()) {
308    default: llvm_unreachable("Unknown loc info!");
309    case CCValAssign::Full: break;
310    case CCValAssign::SExt:
311      Arg = DAG.getNode(ISD::SIGN_EXTEND, VA.getLocVT(), Arg);
312      break;
313    case CCValAssign::ZExt:
314      Arg = DAG.getNode(ISD::ZERO_EXTEND, VA.getLocVT(), Arg);
315      break;
316    case CCValAssign::AExt:
317      Arg = DAG.getNode(ISD::ANY_EXTEND, VA.getLocVT(), Arg);
318      break;
319    }
320
321    // Arguments that can be passed on register must be kept at
322    // RegsToPass vector
323    if (VA.isRegLoc()) {
324      RegsToPass.push_back(std::make_pair(VA.getLocReg(), Arg));
325      continue;
326    }
327
328    assert(VA.isMemLoc());
329
330    // Create a store off the stack pointer for this argument.
331    SDValue StackPtr = DAG.getRegister(SP::O6, MVT::i32);
332    // FIXME: VERIFY THAT 68 IS RIGHT.
333    SDValue PtrOff = DAG.getIntPtrConstant(VA.getLocMemOffset()+68);
334    PtrOff = DAG.getNode(ISD::ADD, MVT::i32, StackPtr, PtrOff);
335    MemOpChains.push_back(DAG.getStore(Chain, Arg, PtrOff, NULL, 0));
336  }
337
338#else
339  static const unsigned ArgRegs[] = {
340    SP::I0, SP::I1, SP::I2, SP::I3, SP::I4, SP::I5
341  };
342  unsigned ArgOffset = 68;
343
344  for (unsigned i = 0, e = Outs.size(); i != e; ++i) {
345    SDValue Val = Outs[i].Val;
346    MVT ObjectVT = Val.getValueType();
347    SDValue ValToStore(0, 0);
348    unsigned ObjSize;
349    switch (ObjectVT.getSimpleVT()) {
350    default: llvm_unreachable("Unhandled argument type!");
351    case MVT::i32:
352      ObjSize = 4;
353
354      if (RegsToPass.size() >= 6) {
355        ValToStore = Val;
356      } else {
357        RegsToPass.push_back(std::make_pair(ArgRegs[RegsToPass.size()], Val));
358      }
359      break;
360    case MVT::f32:
361      ObjSize = 4;
362      if (RegsToPass.size() >= 6) {
363        ValToStore = Val;
364      } else {
365        // Convert this to a FP value in an int reg.
366        Val = DAG.getNode(ISD::BIT_CONVERT, dl, MVT::i32, Val);
367        RegsToPass.push_back(std::make_pair(ArgRegs[RegsToPass.size()], Val));
368      }
369      break;
370    case MVT::f64: {
371      ObjSize = 8;
372      if (RegsToPass.size() >= 6) {
373        ValToStore = Val;    // Whole thing is passed in memory.
374        break;
375      }
376
377      // Break into top and bottom parts by storing to the stack and loading
378      // out the parts as integers.  Top part goes in a reg.
379      SDValue StackPtr = DAG.CreateStackTemporary(MVT::f64, MVT::i32);
380      SDValue Store = DAG.getStore(DAG.getEntryNode(), dl,
381                                   Val, StackPtr, NULL, 0);
382      // Sparc is big-endian, so the high part comes first.
383      SDValue Hi = DAG.getLoad(MVT::i32, dl, Store, StackPtr, NULL, 0, 0);
384      // Increment the pointer to the other half.
385      StackPtr = DAG.getNode(ISD::ADD, dl, StackPtr.getValueType(), StackPtr,
386                             DAG.getIntPtrConstant(4));
387      // Load the low part.
388      SDValue Lo = DAG.getLoad(MVT::i32, dl, Store, StackPtr, NULL, 0, 0);
389
390      RegsToPass.push_back(std::make_pair(ArgRegs[RegsToPass.size()], Hi));
391
392      if (RegsToPass.size() >= 6) {
393        ValToStore = Lo;
394        ArgOffset += 4;
395        ObjSize = 4;
396      } else {
397        RegsToPass.push_back(std::make_pair(ArgRegs[RegsToPass.size()], Lo));
398      }
399      break;
400    }
401    case MVT::i64: {
402      ObjSize = 8;
403      if (RegsToPass.size() >= 6) {
404        ValToStore = Val;    // Whole thing is passed in memory.
405        break;
406      }
407
408      // Split the value into top and bottom part.  Top part goes in a reg.
409      SDValue Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32, Val,
410                                 DAG.getConstant(1, MVT::i32));
411      SDValue Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32, Val,
412                                 DAG.getConstant(0, MVT::i32));
413      RegsToPass.push_back(std::make_pair(ArgRegs[RegsToPass.size()], Hi));
414
415      if (RegsToPass.size() >= 6) {
416        ValToStore = Lo;
417        ArgOffset += 4;
418        ObjSize = 4;
419      } else {
420        RegsToPass.push_back(std::make_pair(ArgRegs[RegsToPass.size()], Lo));
421      }
422      break;
423    }
424    }
425
426    if (ValToStore.getNode()) {
427      SDValue StackPtr = DAG.getRegister(SP::O6, MVT::i32);
428      SDValue PtrOff = DAG.getConstant(ArgOffset, MVT::i32);
429      PtrOff = DAG.getNode(ISD::ADD, dl, MVT::i32, StackPtr, PtrOff);
430      MemOpChains.push_back(DAG.getStore(Chain, dl, ValToStore,
431                                         PtrOff, NULL, 0));
432    }
433    ArgOffset += ObjSize;
434  }
435#endif
436
437  // Emit all stores, make sure the occur before any copies into physregs.
438  if (!MemOpChains.empty())
439    Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
440                        &MemOpChains[0], MemOpChains.size());
441
442  // Build a sequence of copy-to-reg nodes chained together with token
443  // chain and flag operands which copy the outgoing args into registers.
444  // The InFlag in necessary since all emited instructions must be
445  // stuck together.
446  SDValue InFlag;
447  for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i) {
448    unsigned Reg = RegsToPass[i].first;
449    // Remap I0->I7 -> O0->O7.
450    if (Reg >= SP::I0 && Reg <= SP::I7)
451      Reg = Reg-SP::I0+SP::O0;
452
453    Chain = DAG.getCopyToReg(Chain, dl, Reg, RegsToPass[i].second, InFlag);
454    InFlag = Chain.getValue(1);
455  }
456
457  // If the callee is a GlobalAddress node (quite common, every direct call is)
458  // turn it into a TargetGlobalAddress node so that legalize doesn't hack it.
459  // Likewise ExternalSymbol -> TargetExternalSymbol.
460  if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee))
461    Callee = DAG.getTargetGlobalAddress(G->getGlobal(), MVT::i32);
462  else if (ExternalSymbolSDNode *E = dyn_cast<ExternalSymbolSDNode>(Callee))
463    Callee = DAG.getTargetExternalSymbol(E->getSymbol(), MVT::i32);
464
465  std::vector<MVT> NodeTys;
466  NodeTys.push_back(MVT::Other);   // Returns a chain
467  NodeTys.push_back(MVT::Flag);    // Returns a flag for retval copy to use.
468  SDValue Ops[] = { Chain, Callee, InFlag };
469  Chain = DAG.getNode(SPISD::CALL, dl, NodeTys, Ops, InFlag.getNode() ? 3 : 2);
470  InFlag = Chain.getValue(1);
471
472  Chain = DAG.getCALLSEQ_END(Chain, DAG.getIntPtrConstant(ArgsSize, true),
473                             DAG.getIntPtrConstant(0, true), InFlag);
474  InFlag = Chain.getValue(1);
475
476  // Assign locations to each value returned by this call.
477  SmallVector<CCValAssign, 16> RVLocs;
478  CCState RVInfo(CallConv, isVarArg, DAG.getTarget(),
479                 RVLocs, *DAG.getContext());
480
481  RVInfo.AnalyzeCallResult(Ins, RetCC_Sparc32);
482
483  // Copy all of the result registers out of their specified physreg.
484  for (unsigned i = 0; i != RVLocs.size(); ++i) {
485    unsigned Reg = RVLocs[i].getLocReg();
486
487    // Remap I0->I7 -> O0->O7.
488    if (Reg >= SP::I0 && Reg <= SP::I7)
489      Reg = Reg-SP::I0+SP::O0;
490
491    Chain = DAG.getCopyFromReg(Chain, dl, Reg,
492                               RVLocs[i].getValVT(), InFlag).getValue(1);
493    InFlag = Chain.getValue(2);
494    InVals.push_back(Chain.getValue(0));
495  }
496
497  return Chain;
498}
499
500
501
502//===----------------------------------------------------------------------===//
503// TargetLowering Implementation
504//===----------------------------------------------------------------------===//
505
506/// IntCondCCodeToICC - Convert a DAG integer condition code to a SPARC ICC
507/// condition.
508static SPCC::CondCodes IntCondCCodeToICC(ISD::CondCode CC) {
509  switch (CC) {
510  default: llvm_unreachable("Unknown integer condition code!");
511  case ISD::SETEQ:  return SPCC::ICC_E;
512  case ISD::SETNE:  return SPCC::ICC_NE;
513  case ISD::SETLT:  return SPCC::ICC_L;
514  case ISD::SETGT:  return SPCC::ICC_G;
515  case ISD::SETLE:  return SPCC::ICC_LE;
516  case ISD::SETGE:  return SPCC::ICC_GE;
517  case ISD::SETULT: return SPCC::ICC_CS;
518  case ISD::SETULE: return SPCC::ICC_LEU;
519  case ISD::SETUGT: return SPCC::ICC_GU;
520  case ISD::SETUGE: return SPCC::ICC_CC;
521  }
522}
523
524/// FPCondCCodeToFCC - Convert a DAG floatingp oint condition code to a SPARC
525/// FCC condition.
526static SPCC::CondCodes FPCondCCodeToFCC(ISD::CondCode CC) {
527  switch (CC) {
528  default: llvm_unreachable("Unknown fp condition code!");
529  case ISD::SETEQ:
530  case ISD::SETOEQ: return SPCC::FCC_E;
531  case ISD::SETNE:
532  case ISD::SETUNE: return SPCC::FCC_NE;
533  case ISD::SETLT:
534  case ISD::SETOLT: return SPCC::FCC_L;
535  case ISD::SETGT:
536  case ISD::SETOGT: return SPCC::FCC_G;
537  case ISD::SETLE:
538  case ISD::SETOLE: return SPCC::FCC_LE;
539  case ISD::SETGE:
540  case ISD::SETOGE: return SPCC::FCC_GE;
541  case ISD::SETULT: return SPCC::FCC_UL;
542  case ISD::SETULE: return SPCC::FCC_ULE;
543  case ISD::SETUGT: return SPCC::FCC_UG;
544  case ISD::SETUGE: return SPCC::FCC_UGE;
545  case ISD::SETUO:  return SPCC::FCC_U;
546  case ISD::SETO:   return SPCC::FCC_O;
547  case ISD::SETONE: return SPCC::FCC_LG;
548  case ISD::SETUEQ: return SPCC::FCC_UE;
549  }
550}
551
552class TargetLoweringObjectFileSparc : public TargetLoweringObjectFileELF {
553public:
554  void getSectionFlagsAsString(SectionKind Kind,
555                               SmallVectorImpl<char> &Str) const {
556    if (Kind.isMergeableConst() || Kind.isMergeableCString())
557      return TargetLoweringObjectFileELF::getSectionFlagsAsString(Kind, Str);
558
559    // FIXME: Inefficient.
560    std::string Res;
561    if (!Kind.isMetadata())
562      Res += ",#alloc";
563    if (Kind.isText())
564      Res += ",#execinstr";
565    if (Kind.isWriteable())
566      Res += ",#write";
567    if (Kind.isThreadLocal())
568      Res += ",#tls";
569
570    Str.append(Res.begin(), Res.end());
571  }
572};
573
574
575SparcTargetLowering::SparcTargetLowering(TargetMachine &TM)
576  : TargetLowering(TM, new TargetLoweringObjectFileSparc()) {
577
578  // Set up the register classes.
579  addRegisterClass(MVT::i32, SP::IntRegsRegisterClass);
580  addRegisterClass(MVT::f32, SP::FPRegsRegisterClass);
581  addRegisterClass(MVT::f64, SP::DFPRegsRegisterClass);
582
583  // Turn FP extload into load/fextend
584  setLoadExtAction(ISD::EXTLOAD, MVT::f32, Expand);
585  // Sparc doesn't have i1 sign extending load
586  setLoadExtAction(ISD::SEXTLOAD, MVT::i1, Promote);
587  // Turn FP truncstore into trunc + store.
588  setTruncStoreAction(MVT::f64, MVT::f32, Expand);
589
590  // Custom legalize GlobalAddress nodes into LO/HI parts.
591  setOperationAction(ISD::GlobalAddress, MVT::i32, Custom);
592  setOperationAction(ISD::GlobalTLSAddress, MVT::i32, Custom);
593  setOperationAction(ISD::ConstantPool , MVT::i32, Custom);
594
595  // Sparc doesn't have sext_inreg, replace them with shl/sra
596  setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i16, Expand);
597  setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i8 , Expand);
598  setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i1 , Expand);
599
600  // Sparc has no REM or DIVREM operations.
601  setOperationAction(ISD::UREM, MVT::i32, Expand);
602  setOperationAction(ISD::SREM, MVT::i32, Expand);
603  setOperationAction(ISD::SDIVREM, MVT::i32, Expand);
604  setOperationAction(ISD::UDIVREM, MVT::i32, Expand);
605
606  // Custom expand fp<->sint
607  setOperationAction(ISD::FP_TO_SINT, MVT::i32, Custom);
608  setOperationAction(ISD::SINT_TO_FP, MVT::i32, Custom);
609
610  // Expand fp<->uint
611  setOperationAction(ISD::FP_TO_UINT, MVT::i32, Expand);
612  setOperationAction(ISD::UINT_TO_FP, MVT::i32, Expand);
613
614  setOperationAction(ISD::BIT_CONVERT, MVT::f32, Expand);
615  setOperationAction(ISD::BIT_CONVERT, MVT::i32, Expand);
616
617  // Sparc has no select or setcc: expand to SELECT_CC.
618  setOperationAction(ISD::SELECT, MVT::i32, Expand);
619  setOperationAction(ISD::SELECT, MVT::f32, Expand);
620  setOperationAction(ISD::SELECT, MVT::f64, Expand);
621  setOperationAction(ISD::SETCC, MVT::i32, Expand);
622  setOperationAction(ISD::SETCC, MVT::f32, Expand);
623  setOperationAction(ISD::SETCC, MVT::f64, Expand);
624
625  // Sparc doesn't have BRCOND either, it has BR_CC.
626  setOperationAction(ISD::BRCOND, MVT::Other, Expand);
627  setOperationAction(ISD::BRIND, MVT::Other, Expand);
628  setOperationAction(ISD::BR_JT, MVT::Other, Expand);
629  setOperationAction(ISD::BR_CC, MVT::i32, Custom);
630  setOperationAction(ISD::BR_CC, MVT::f32, Custom);
631  setOperationAction(ISD::BR_CC, MVT::f64, Custom);
632
633  setOperationAction(ISD::SELECT_CC, MVT::i32, Custom);
634  setOperationAction(ISD::SELECT_CC, MVT::f32, Custom);
635  setOperationAction(ISD::SELECT_CC, MVT::f64, Custom);
636
637  // SPARC has no intrinsics for these particular operations.
638  setOperationAction(ISD::MEMBARRIER, MVT::Other, Expand);
639
640  setOperationAction(ISD::FSIN , MVT::f64, Expand);
641  setOperationAction(ISD::FCOS , MVT::f64, Expand);
642  setOperationAction(ISD::FREM , MVT::f64, Expand);
643  setOperationAction(ISD::FSIN , MVT::f32, Expand);
644  setOperationAction(ISD::FCOS , MVT::f32, Expand);
645  setOperationAction(ISD::FREM , MVT::f32, Expand);
646  setOperationAction(ISD::CTPOP, MVT::i32, Expand);
647  setOperationAction(ISD::CTTZ , MVT::i32, Expand);
648  setOperationAction(ISD::CTLZ , MVT::i32, Expand);
649  setOperationAction(ISD::ROTL , MVT::i32, Expand);
650  setOperationAction(ISD::ROTR , MVT::i32, Expand);
651  setOperationAction(ISD::BSWAP, MVT::i32, Expand);
652  setOperationAction(ISD::FCOPYSIGN, MVT::f64, Expand);
653  setOperationAction(ISD::FCOPYSIGN, MVT::f32, Expand);
654  setOperationAction(ISD::FPOW , MVT::f64, Expand);
655  setOperationAction(ISD::FPOW , MVT::f32, Expand);
656
657  setOperationAction(ISD::SHL_PARTS, MVT::i32, Expand);
658  setOperationAction(ISD::SRA_PARTS, MVT::i32, Expand);
659  setOperationAction(ISD::SRL_PARTS, MVT::i32, Expand);
660
661  // FIXME: Sparc provides these multiplies, but we don't have them yet.
662  setOperationAction(ISD::UMUL_LOHI, MVT::i32, Expand);
663  setOperationAction(ISD::SMUL_LOHI, MVT::i32, Expand);
664
665  // We don't have line number support yet.
666  setOperationAction(ISD::DBG_STOPPOINT, MVT::Other, Expand);
667  setOperationAction(ISD::DEBUG_LOC, MVT::Other, Expand);
668  setOperationAction(ISD::DBG_LABEL, MVT::Other, Expand);
669  setOperationAction(ISD::EH_LABEL, MVT::Other, Expand);
670
671  // VASTART needs to be custom lowered to use the VarArgsFrameIndex.
672  setOperationAction(ISD::VASTART           , MVT::Other, Custom);
673  // VAARG needs to be lowered to not do unaligned accesses for doubles.
674  setOperationAction(ISD::VAARG             , MVT::Other, Custom);
675
676  // Use the default implementation.
677  setOperationAction(ISD::VACOPY            , MVT::Other, Expand);
678  setOperationAction(ISD::VAEND             , MVT::Other, Expand);
679  setOperationAction(ISD::STACKSAVE         , MVT::Other, Expand);
680  setOperationAction(ISD::STACKRESTORE      , MVT::Other, Expand);
681  setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32  , Custom);
682
683  // No debug info support yet.
684  setOperationAction(ISD::DBG_STOPPOINT, MVT::Other, Expand);
685  setOperationAction(ISD::DBG_LABEL, MVT::Other, Expand);
686  setOperationAction(ISD::EH_LABEL, MVT::Other, Expand);
687  setOperationAction(ISD::DECLARE, MVT::Other, Expand);
688
689  setStackPointerRegisterToSaveRestore(SP::O6);
690
691  if (TM.getSubtarget<SparcSubtarget>().isV9())
692    setOperationAction(ISD::CTPOP, MVT::i32, Legal);
693
694  computeRegisterProperties();
695}
696
697const char *SparcTargetLowering::getTargetNodeName(unsigned Opcode) const {
698  switch (Opcode) {
699  default: return 0;
700  case SPISD::CMPICC:     return "SPISD::CMPICC";
701  case SPISD::CMPFCC:     return "SPISD::CMPFCC";
702  case SPISD::BRICC:      return "SPISD::BRICC";
703  case SPISD::BRFCC:      return "SPISD::BRFCC";
704  case SPISD::SELECT_ICC: return "SPISD::SELECT_ICC";
705  case SPISD::SELECT_FCC: return "SPISD::SELECT_FCC";
706  case SPISD::Hi:         return "SPISD::Hi";
707  case SPISD::Lo:         return "SPISD::Lo";
708  case SPISD::FTOI:       return "SPISD::FTOI";
709  case SPISD::ITOF:       return "SPISD::ITOF";
710  case SPISD::CALL:       return "SPISD::CALL";
711  case SPISD::RET_FLAG:   return "SPISD::RET_FLAG";
712  }
713}
714
715/// isMaskedValueZeroForTargetNode - Return true if 'Op & Mask' is known to
716/// be zero. Op is expected to be a target specific node. Used by DAG
717/// combiner.
718void SparcTargetLowering::computeMaskedBitsForTargetNode(const SDValue Op,
719                                                         const APInt &Mask,
720                                                         APInt &KnownZero,
721                                                         APInt &KnownOne,
722                                                         const SelectionDAG &DAG,
723                                                         unsigned Depth) const {
724  APInt KnownZero2, KnownOne2;
725  KnownZero = KnownOne = APInt(Mask.getBitWidth(), 0);   // Don't know anything.
726
727  switch (Op.getOpcode()) {
728  default: break;
729  case SPISD::SELECT_ICC:
730  case SPISD::SELECT_FCC:
731    DAG.ComputeMaskedBits(Op.getOperand(1), Mask, KnownZero, KnownOne,
732                          Depth+1);
733    DAG.ComputeMaskedBits(Op.getOperand(0), Mask, KnownZero2, KnownOne2,
734                          Depth+1);
735    assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
736    assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?");
737
738    // Only known if known in both the LHS and RHS.
739    KnownOne &= KnownOne2;
740    KnownZero &= KnownZero2;
741    break;
742  }
743}
744
745// Look at LHS/RHS/CC and see if they are a lowered setcc instruction.  If so
746// set LHS/RHS and SPCC to the LHS/RHS of the setcc and SPCC to the condition.
747static void LookThroughSetCC(SDValue &LHS, SDValue &RHS,
748                             ISD::CondCode CC, unsigned &SPCC) {
749  if (isa<ConstantSDNode>(RHS) &&
750      cast<ConstantSDNode>(RHS)->getZExtValue() == 0 &&
751      CC == ISD::SETNE &&
752      ((LHS.getOpcode() == SPISD::SELECT_ICC &&
753        LHS.getOperand(3).getOpcode() == SPISD::CMPICC) ||
754       (LHS.getOpcode() == SPISD::SELECT_FCC &&
755        LHS.getOperand(3).getOpcode() == SPISD::CMPFCC)) &&
756      isa<ConstantSDNode>(LHS.getOperand(0)) &&
757      isa<ConstantSDNode>(LHS.getOperand(1)) &&
758      cast<ConstantSDNode>(LHS.getOperand(0))->getZExtValue() == 1 &&
759      cast<ConstantSDNode>(LHS.getOperand(1))->getZExtValue() == 0) {
760    SDValue CMPCC = LHS.getOperand(3);
761    SPCC = cast<ConstantSDNode>(LHS.getOperand(2))->getZExtValue();
762    LHS = CMPCC.getOperand(0);
763    RHS = CMPCC.getOperand(1);
764  }
765}
766
767static SDValue LowerGLOBALADDRESS(SDValue Op, SelectionDAG &DAG) {
768  GlobalValue *GV = cast<GlobalAddressSDNode>(Op)->getGlobal();
769  // FIXME there isn't really any debug info here
770  DebugLoc dl = Op.getDebugLoc();
771  SDValue GA = DAG.getTargetGlobalAddress(GV, MVT::i32);
772  SDValue Hi = DAG.getNode(SPISD::Hi, dl, MVT::i32, GA);
773  SDValue Lo = DAG.getNode(SPISD::Lo, dl, MVT::i32, GA);
774  return DAG.getNode(ISD::ADD, dl, MVT::i32, Lo, Hi);
775}
776
777static SDValue LowerCONSTANTPOOL(SDValue Op, SelectionDAG &DAG) {
778  ConstantPoolSDNode *N = cast<ConstantPoolSDNode>(Op);
779  // FIXME there isn't really any debug info here
780  DebugLoc dl = Op.getDebugLoc();
781  Constant *C = N->getConstVal();
782  SDValue CP = DAG.getTargetConstantPool(C, MVT::i32, N->getAlignment());
783  SDValue Hi = DAG.getNode(SPISD::Hi, dl, MVT::i32, CP);
784  SDValue Lo = DAG.getNode(SPISD::Lo, dl, MVT::i32, CP);
785  return DAG.getNode(ISD::ADD, dl, MVT::i32, Lo, Hi);
786}
787
788static SDValue LowerFP_TO_SINT(SDValue Op, SelectionDAG &DAG) {
789  DebugLoc dl = Op.getDebugLoc();
790  // Convert the fp value to integer in an FP register.
791  assert(Op.getValueType() == MVT::i32);
792  Op = DAG.getNode(SPISD::FTOI, dl, MVT::f32, Op.getOperand(0));
793  return DAG.getNode(ISD::BIT_CONVERT, dl, MVT::i32, Op);
794}
795
796static SDValue LowerSINT_TO_FP(SDValue Op, SelectionDAG &DAG) {
797  DebugLoc dl = Op.getDebugLoc();
798  assert(Op.getOperand(0).getValueType() == MVT::i32);
799  SDValue Tmp = DAG.getNode(ISD::BIT_CONVERT, dl, MVT::f32, Op.getOperand(0));
800  // Convert the int value to FP in an FP register.
801  return DAG.getNode(SPISD::ITOF, dl, Op.getValueType(), Tmp);
802}
803
804static SDValue LowerBR_CC(SDValue Op, SelectionDAG &DAG) {
805  SDValue Chain = Op.getOperand(0);
806  ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(1))->get();
807  SDValue LHS = Op.getOperand(2);
808  SDValue RHS = Op.getOperand(3);
809  SDValue Dest = Op.getOperand(4);
810  DebugLoc dl = Op.getDebugLoc();
811  unsigned Opc, SPCC = ~0U;
812
813  // If this is a br_cc of a "setcc", and if the setcc got lowered into
814  // an CMP[IF]CC/SELECT_[IF]CC pair, find the original compared values.
815  LookThroughSetCC(LHS, RHS, CC, SPCC);
816
817  // Get the condition flag.
818  SDValue CompareFlag;
819  if (LHS.getValueType() == MVT::i32) {
820    std::vector<MVT> VTs;
821    VTs.push_back(MVT::i32);
822    VTs.push_back(MVT::Flag);
823    SDValue Ops[2] = { LHS, RHS };
824    CompareFlag = DAG.getNode(SPISD::CMPICC, dl, VTs, Ops, 2).getValue(1);
825    if (SPCC == ~0U) SPCC = IntCondCCodeToICC(CC);
826    Opc = SPISD::BRICC;
827  } else {
828    CompareFlag = DAG.getNode(SPISD::CMPFCC, dl, MVT::Flag, LHS, RHS);
829    if (SPCC == ~0U) SPCC = FPCondCCodeToFCC(CC);
830    Opc = SPISD::BRFCC;
831  }
832  return DAG.getNode(Opc, dl, MVT::Other, Chain, Dest,
833                     DAG.getConstant(SPCC, MVT::i32), CompareFlag);
834}
835
836static SDValue LowerSELECT_CC(SDValue Op, SelectionDAG &DAG) {
837  SDValue LHS = Op.getOperand(0);
838  SDValue RHS = Op.getOperand(1);
839  ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(4))->get();
840  SDValue TrueVal = Op.getOperand(2);
841  SDValue FalseVal = Op.getOperand(3);
842  DebugLoc dl = Op.getDebugLoc();
843  unsigned Opc, SPCC = ~0U;
844
845  // If this is a select_cc of a "setcc", and if the setcc got lowered into
846  // an CMP[IF]CC/SELECT_[IF]CC pair, find the original compared values.
847  LookThroughSetCC(LHS, RHS, CC, SPCC);
848
849  SDValue CompareFlag;
850  if (LHS.getValueType() == MVT::i32) {
851    std::vector<MVT> VTs;
852    VTs.push_back(LHS.getValueType());   // subcc returns a value
853    VTs.push_back(MVT::Flag);
854    SDValue Ops[2] = { LHS, RHS };
855    CompareFlag = DAG.getNode(SPISD::CMPICC, dl, VTs, Ops, 2).getValue(1);
856    Opc = SPISD::SELECT_ICC;
857    if (SPCC == ~0U) SPCC = IntCondCCodeToICC(CC);
858  } else {
859    CompareFlag = DAG.getNode(SPISD::CMPFCC, dl, MVT::Flag, LHS, RHS);
860    Opc = SPISD::SELECT_FCC;
861    if (SPCC == ~0U) SPCC = FPCondCCodeToFCC(CC);
862  }
863  return DAG.getNode(Opc, dl, TrueVal.getValueType(), TrueVal, FalseVal,
864                     DAG.getConstant(SPCC, MVT::i32), CompareFlag);
865}
866
867static SDValue LowerVASTART(SDValue Op, SelectionDAG &DAG,
868                              SparcTargetLowering &TLI) {
869  // vastart just stores the address of the VarArgsFrameIndex slot into the
870  // memory location argument.
871  DebugLoc dl = Op.getDebugLoc();
872  SDValue Offset = DAG.getNode(ISD::ADD, dl, MVT::i32,
873                                 DAG.getRegister(SP::I6, MVT::i32),
874                                 DAG.getConstant(TLI.getVarArgsFrameOffset(),
875                                                 MVT::i32));
876  const Value *SV = cast<SrcValueSDNode>(Op.getOperand(2))->getValue();
877  return DAG.getStore(Op.getOperand(0), dl, Offset, Op.getOperand(1), SV, 0);
878}
879
880static SDValue LowerVAARG(SDValue Op, SelectionDAG &DAG) {
881  SDNode *Node = Op.getNode();
882  MVT VT = Node->getValueType(0);
883  SDValue InChain = Node->getOperand(0);
884  SDValue VAListPtr = Node->getOperand(1);
885  const Value *SV = cast<SrcValueSDNode>(Node->getOperand(2))->getValue();
886  DebugLoc dl = Node->getDebugLoc();
887  SDValue VAList = DAG.getLoad(MVT::i32, dl, InChain, VAListPtr, SV, 0);
888  // Increment the pointer, VAList, to the next vaarg
889  SDValue NextPtr = DAG.getNode(ISD::ADD, dl, MVT::i32, VAList,
890                                  DAG.getConstant(VT.getSizeInBits()/8,
891                                                  MVT::i32));
892  // Store the incremented VAList to the legalized pointer
893  InChain = DAG.getStore(VAList.getValue(1), dl, NextPtr,
894                         VAListPtr, SV, 0);
895  // Load the actual argument out of the pointer VAList, unless this is an
896  // f64 load.
897  if (VT != MVT::f64)
898    return DAG.getLoad(VT, dl, InChain, VAList, NULL, 0);
899
900  // Otherwise, load it as i64, then do a bitconvert.
901  SDValue V = DAG.getLoad(MVT::i64, dl, InChain, VAList, NULL, 0);
902
903  // Bit-Convert the value to f64.
904  SDValue Ops[2] = {
905    DAG.getNode(ISD::BIT_CONVERT, dl, MVT::f64, V),
906    V.getValue(1)
907  };
908  return DAG.getMergeValues(Ops, 2, dl);
909}
910
911static SDValue LowerDYNAMIC_STACKALLOC(SDValue Op, SelectionDAG &DAG) {
912  SDValue Chain = Op.getOperand(0);  // Legalize the chain.
913  SDValue Size  = Op.getOperand(1);  // Legalize the size.
914  DebugLoc dl = Op.getDebugLoc();
915
916  unsigned SPReg = SP::O6;
917  SDValue SP = DAG.getCopyFromReg(Chain, dl, SPReg, MVT::i32);
918  SDValue NewSP = DAG.getNode(ISD::SUB, dl, MVT::i32, SP, Size); // Value
919  Chain = DAG.getCopyToReg(SP.getValue(1), dl, SPReg, NewSP);    // Output chain
920
921  // The resultant pointer is actually 16 words from the bottom of the stack,
922  // to provide a register spill area.
923  SDValue NewVal = DAG.getNode(ISD::ADD, dl, MVT::i32, NewSP,
924                                 DAG.getConstant(96, MVT::i32));
925  SDValue Ops[2] = { NewVal, Chain };
926  return DAG.getMergeValues(Ops, 2, dl);
927}
928
929
930SDValue SparcTargetLowering::
931LowerOperation(SDValue Op, SelectionDAG &DAG) {
932  switch (Op.getOpcode()) {
933  default: llvm_unreachable("Should not custom lower this!");
934  // Frame & Return address.  Currently unimplemented
935  case ISD::RETURNADDR: return SDValue();
936  case ISD::FRAMEADDR:  return SDValue();
937  case ISD::GlobalTLSAddress:
938    llvm_unreachable("TLS not implemented for Sparc.");
939  case ISD::GlobalAddress:      return LowerGLOBALADDRESS(Op, DAG);
940  case ISD::ConstantPool:       return LowerCONSTANTPOOL(Op, DAG);
941  case ISD::FP_TO_SINT:         return LowerFP_TO_SINT(Op, DAG);
942  case ISD::SINT_TO_FP:         return LowerSINT_TO_FP(Op, DAG);
943  case ISD::BR_CC:              return LowerBR_CC(Op, DAG);
944  case ISD::SELECT_CC:          return LowerSELECT_CC(Op, DAG);
945  case ISD::VASTART:            return LowerVASTART(Op, DAG, *this);
946  case ISD::VAARG:              return LowerVAARG(Op, DAG);
947  case ISD::DYNAMIC_STACKALLOC: return LowerDYNAMIC_STACKALLOC(Op, DAG);
948  }
949}
950
951MachineBasicBlock *
952SparcTargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
953                                                 MachineBasicBlock *BB) const {
954  const TargetInstrInfo &TII = *getTargetMachine().getInstrInfo();
955  unsigned BROpcode;
956  unsigned CC;
957  DebugLoc dl = MI->getDebugLoc();
958  // Figure out the conditional branch opcode to use for this select_cc.
959  switch (MI->getOpcode()) {
960  default: llvm_unreachable("Unknown SELECT_CC!");
961  case SP::SELECT_CC_Int_ICC:
962  case SP::SELECT_CC_FP_ICC:
963  case SP::SELECT_CC_DFP_ICC:
964    BROpcode = SP::BCOND;
965    break;
966  case SP::SELECT_CC_Int_FCC:
967  case SP::SELECT_CC_FP_FCC:
968  case SP::SELECT_CC_DFP_FCC:
969    BROpcode = SP::FBCOND;
970    break;
971  }
972
973  CC = (SPCC::CondCodes)MI->getOperand(3).getImm();
974
975  // To "insert" a SELECT_CC instruction, we actually have to insert the diamond
976  // control-flow pattern.  The incoming instruction knows the destination vreg
977  // to set, the condition code register to branch on, the true/false values to
978  // select between, and a branch opcode to use.
979  const BasicBlock *LLVM_BB = BB->getBasicBlock();
980  MachineFunction::iterator It = BB;
981  ++It;
982
983  //  thisMBB:
984  //  ...
985  //   TrueVal = ...
986  //   [f]bCC copy1MBB
987  //   fallthrough --> copy0MBB
988  MachineBasicBlock *thisMBB = BB;
989  MachineFunction *F = BB->getParent();
990  MachineBasicBlock *copy0MBB = F->CreateMachineBasicBlock(LLVM_BB);
991  MachineBasicBlock *sinkMBB = F->CreateMachineBasicBlock(LLVM_BB);
992  BuildMI(BB, dl, TII.get(BROpcode)).addMBB(sinkMBB).addImm(CC);
993  F->insert(It, copy0MBB);
994  F->insert(It, sinkMBB);
995  // Update machine-CFG edges by transferring all successors of the current
996  // block to the new block which will contain the Phi node for the select.
997  sinkMBB->transferSuccessors(BB);
998  // Next, add the true and fallthrough blocks as its successors.
999  BB->addSuccessor(copy0MBB);
1000  BB->addSuccessor(sinkMBB);
1001
1002  //  copy0MBB:
1003  //   %FalseValue = ...
1004  //   # fallthrough to sinkMBB
1005  BB = copy0MBB;
1006
1007  // Update machine-CFG edges
1008  BB->addSuccessor(sinkMBB);
1009
1010  //  sinkMBB:
1011  //   %Result = phi [ %FalseValue, copy0MBB ], [ %TrueValue, thisMBB ]
1012  //  ...
1013  BB = sinkMBB;
1014  BuildMI(BB, dl, TII.get(SP::PHI), MI->getOperand(0).getReg())
1015    .addReg(MI->getOperand(2).getReg()).addMBB(copy0MBB)
1016    .addReg(MI->getOperand(1).getReg()).addMBB(thisMBB);
1017
1018  F->DeleteMachineInstr(MI);   // The pseudo instruction is gone now.
1019  return BB;
1020}
1021
1022//===----------------------------------------------------------------------===//
1023//                         Sparc Inline Assembly Support
1024//===----------------------------------------------------------------------===//
1025
1026/// getConstraintType - Given a constraint letter, return the type of
1027/// constraint it is for this target.
1028SparcTargetLowering::ConstraintType
1029SparcTargetLowering::getConstraintType(const std::string &Constraint) const {
1030  if (Constraint.size() == 1) {
1031    switch (Constraint[0]) {
1032    default:  break;
1033    case 'r': return C_RegisterClass;
1034    }
1035  }
1036
1037  return TargetLowering::getConstraintType(Constraint);
1038}
1039
1040std::pair<unsigned, const TargetRegisterClass*>
1041SparcTargetLowering::getRegForInlineAsmConstraint(const std::string &Constraint,
1042                                                  MVT VT) const {
1043  if (Constraint.size() == 1) {
1044    switch (Constraint[0]) {
1045    case 'r':
1046      return std::make_pair(0U, SP::IntRegsRegisterClass);
1047    }
1048  }
1049
1050  return TargetLowering::getRegForInlineAsmConstraint(Constraint, VT);
1051}
1052
1053std::vector<unsigned> SparcTargetLowering::
1054getRegClassForInlineAsmConstraint(const std::string &Constraint,
1055                                  MVT VT) const {
1056  if (Constraint.size() != 1)
1057    return std::vector<unsigned>();
1058
1059  switch (Constraint[0]) {
1060  default: break;
1061  case 'r':
1062    return make_vector<unsigned>(SP::L0, SP::L1, SP::L2, SP::L3,
1063                                 SP::L4, SP::L5, SP::L6, SP::L7,
1064                                 SP::I0, SP::I1, SP::I2, SP::I3,
1065                                 SP::I4, SP::I5,
1066                                 SP::O0, SP::O1, SP::O2, SP::O3,
1067                                 SP::O4, SP::O5, SP::O7, 0);
1068  }
1069
1070  return std::vector<unsigned>();
1071}
1072
1073bool
1074SparcTargetLowering::isOffsetFoldingLegal(const GlobalAddressSDNode *GA) const {
1075  // The Sparc target isn't yet aware of offsets.
1076  return false;
1077}
1078
1079/// getFunctionAlignment - Return the Log2 alignment of this function.
1080unsigned SparcTargetLowering::getFunctionAlignment(const Function *) const {
1081  return 4;
1082}
1083