SparcISelDAGToDAG.cpp revision 7a4d2913ea04b708c191595ad6f1841abd36b077 
1//===-- SparcV8ISelDAGToDAG.cpp - A dag to dag inst selector for SparcV8 --===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file was developed by Chris Lattner and is distributed under
6// the University of Illinois Open Source License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file defines an instruction selector for the V8 target
11//
12//===----------------------------------------------------------------------===//
13
14#include "SparcV8.h"
15#include "SparcV8TargetMachine.h"
16#include "llvm/DerivedTypes.h"
17#include "llvm/Function.h"
18#include "llvm/CodeGen/MachineFrameInfo.h"
19#include "llvm/CodeGen/MachineFunction.h"
20#include "llvm/CodeGen/MachineInstrBuilder.h"
21#include "llvm/CodeGen/SelectionDAG.h"
22#include "llvm/CodeGen/SelectionDAGISel.h"
23#include "llvm/CodeGen/SSARegMap.h"
24#include "llvm/Target/TargetLowering.h"
25#include "llvm/Support/Debug.h"
26#include <iostream>
27using namespace llvm;
28
29//===----------------------------------------------------------------------===//
30// TargetLowering Implementation
31//===----------------------------------------------------------------------===//
32
33namespace V8ISD {
34  enum {
35    FIRST_NUMBER = ISD::BUILTIN_OP_END+V8::INSTRUCTION_LIST_END,
36    CMPICC,      // Compare two GPR operands, set icc.
37    CMPFCC,      // Compare two FP operands, set fcc.
38    BRICC,       // Branch to dest on icc condition
39    BRFCC,       // Branch to dest on fcc condition
40    SELECT_ICC,  // Select between two values using the current ICC flags.
41    SELECT_FCC,  // Select between two values using the current FCC flags.
42
43    Hi, Lo,      // Hi/Lo operations, typically on a global address.
44
45    FTOI,        // FP to Int within a FP register.
46    ITOF,        // Int to FP within a FP register.
47
48    CALL,        // A V8 call instruction.
49    RET_FLAG,    // Return with a flag operand.
50  };
51}
52
53/// IntCondCCodeToICC - Convert a DAG integer condition code to a SPARC ICC
54/// condition.
55static V8CC::CondCodes IntCondCCodeToICC(ISD::CondCode CC) {
56  switch (CC) {
57  default: assert(0 && "Unknown integer condition code!");
58  case ISD::SETEQ:  return V8CC::ICC_E;
59  case ISD::SETNE:  return V8CC::ICC_NE;
60  case ISD::SETLT:  return V8CC::ICC_L;
61  case ISD::SETGT:  return V8CC::ICC_G;
62  case ISD::SETLE:  return V8CC::ICC_LE;
63  case ISD::SETGE:  return V8CC::ICC_GE;
64  case ISD::SETULT: return V8CC::ICC_CS;
65  case ISD::SETULE: return V8CC::ICC_LEU;
66  case ISD::SETUGT: return V8CC::ICC_GU;
67  case ISD::SETUGE: return V8CC::ICC_CC;
68  }
69}
70
71/// FPCondCCodeToFCC - Convert a DAG floatingp oint condition code to a SPARC
72/// FCC condition.
73static V8CC::CondCodes FPCondCCodeToFCC(ISD::CondCode CC) {
74  switch (CC) {
75  default: assert(0 && "Unknown fp condition code!");
76  case ISD::SETEQ:  return V8CC::FCC_E;
77  case ISD::SETNE:  return V8CC::FCC_NE;
78  case ISD::SETLT:  return V8CC::FCC_L;
79  case ISD::SETGT:  return V8CC::FCC_G;
80  case ISD::SETLE:  return V8CC::FCC_LE;
81  case ISD::SETGE:  return V8CC::FCC_GE;
82  case ISD::SETULT: return V8CC::FCC_UL;
83  case ISD::SETULE: return V8CC::FCC_ULE;
84  case ISD::SETUGT: return V8CC::FCC_UG;
85  case ISD::SETUGE: return V8CC::FCC_UGE;
86  case ISD::SETUO:  return V8CC::FCC_U;
87  case ISD::SETO:   return V8CC::FCC_O;
88  case ISD::SETONE: return V8CC::FCC_LG;
89  case ISD::SETUEQ: return V8CC::FCC_UE;
90  }
91}
92
93namespace {
94  class SparcV8TargetLowering : public TargetLowering {
95    int VarArgsFrameOffset;   // Frame offset to start of varargs area.
96  public:
97    SparcV8TargetLowering(TargetMachine &TM);
98    virtual SDOperand LowerOperation(SDOperand Op, SelectionDAG &DAG);
99
100    /// isMaskedValueZeroForTargetNode - Return true if 'Op & Mask' is known to
101    /// be zero. Op is expected to be a target specific node. Used by DAG
102    /// combiner.
103    virtual bool isMaskedValueZeroForTargetNode(const SDOperand &Op,
104                                                uint64_t Mask) const;
105
106    virtual std::vector<SDOperand>
107      LowerArguments(Function &F, SelectionDAG &DAG);
108    virtual std::pair<SDOperand, SDOperand>
109      LowerCallTo(SDOperand Chain, const Type *RetTy, bool isVarArg,
110                  unsigned CC,
111                  bool isTailCall, SDOperand Callee, ArgListTy &Args,
112                  SelectionDAG &DAG);
113    virtual std::pair<SDOperand, SDOperand>
114      LowerFrameReturnAddress(bool isFrameAddr, SDOperand Chain, unsigned Depth,
115                              SelectionDAG &DAG);
116    virtual MachineBasicBlock *InsertAtEndOfBasicBlock(MachineInstr *MI,
117                                                       MachineBasicBlock *MBB);
118
119    virtual const char *getTargetNodeName(unsigned Opcode) const;
120  };
121}
122
123SparcV8TargetLowering::SparcV8TargetLowering(TargetMachine &TM)
124  : TargetLowering(TM) {
125
126  // Set up the register classes.
127  addRegisterClass(MVT::i32, V8::IntRegsRegisterClass);
128  addRegisterClass(MVT::f32, V8::FPRegsRegisterClass);
129  addRegisterClass(MVT::f64, V8::DFPRegsRegisterClass);
130
131  // Custom legalize GlobalAddress nodes into LO/HI parts.
132  setOperationAction(ISD::GlobalAddress, MVT::i32, Custom);
133  setOperationAction(ISD::ConstantPool , MVT::i32, Custom);
134
135  // Sparc doesn't have sext_inreg, replace them with shl/sra
136  setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i16, Expand);
137  setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i8 , Expand);
138  setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i1 , Expand);
139
140  // Sparc has no REM operation.
141  setOperationAction(ISD::UREM, MVT::i32, Expand);
142  setOperationAction(ISD::SREM, MVT::i32, Expand);
143
144  // Custom expand fp<->sint
145  setOperationAction(ISD::FP_TO_SINT, MVT::i32, Custom);
146  setOperationAction(ISD::SINT_TO_FP, MVT::i32, Custom);
147
148  // Expand fp<->uint
149  setOperationAction(ISD::FP_TO_UINT, MVT::i32, Expand);
150  setOperationAction(ISD::UINT_TO_FP, MVT::i32, Expand);
151
152  setOperationAction(ISD::BIT_CONVERT, MVT::f32, Expand);
153  setOperationAction(ISD::BIT_CONVERT, MVT::i32, Expand);
154
155  // Turn FP extload into load/fextend
156  setOperationAction(ISD::EXTLOAD, MVT::f32, Expand);
157
158  // Sparc has no select or setcc: expand to SELECT_CC.
159  setOperationAction(ISD::SELECT, MVT::i32, Expand);
160  setOperationAction(ISD::SELECT, MVT::f32, Expand);
161  setOperationAction(ISD::SELECT, MVT::f64, Expand);
162  setOperationAction(ISD::SETCC, MVT::i32, Expand);
163  setOperationAction(ISD::SETCC, MVT::f32, Expand);
164  setOperationAction(ISD::SETCC, MVT::f64, Expand);
165
166  // Sparc doesn't have BRCOND either, it has BR_CC.
167  setOperationAction(ISD::BRCOND, MVT::Other, Expand);
168  setOperationAction(ISD::BRCONDTWOWAY, MVT::Other, Expand);
169  setOperationAction(ISD::BRTWOWAY_CC, MVT::Other, Expand);
170  setOperationAction(ISD::BR_CC, MVT::i32, Custom);
171  setOperationAction(ISD::BR_CC, MVT::f32, Custom);
172  setOperationAction(ISD::BR_CC, MVT::f64, Custom);
173
174  setOperationAction(ISD::SELECT_CC, MVT::i32, Custom);
175  setOperationAction(ISD::SELECT_CC, MVT::f32, Custom);
176  setOperationAction(ISD::SELECT_CC, MVT::f64, Custom);
177
178  // V8 has no intrinsics for these particular operations.
179  setOperationAction(ISD::MEMMOVE, MVT::Other, Expand);
180  setOperationAction(ISD::MEMSET, MVT::Other, Expand);
181  setOperationAction(ISD::MEMCPY, MVT::Other, Expand);
182
183  setOperationAction(ISD::FSIN , MVT::f64, Expand);
184  setOperationAction(ISD::FCOS , MVT::f64, Expand);
185  setOperationAction(ISD::FSIN , MVT::f32, Expand);
186  setOperationAction(ISD::FCOS , MVT::f32, Expand);
187  setOperationAction(ISD::CTPOP, MVT::i32, Expand);
188  setOperationAction(ISD::CTTZ , MVT::i32, Expand);
189  setOperationAction(ISD::CTLZ , MVT::i32, Expand);
190  setOperationAction(ISD::ROTL , MVT::i32, Expand);
191  setOperationAction(ISD::ROTR , MVT::i32, Expand);
192  setOperationAction(ISD::BSWAP, MVT::i32, Expand);
193
194  setOperationAction(ISD::SHL_PARTS, MVT::i32, Expand);
195  setOperationAction(ISD::SRA_PARTS, MVT::i32, Expand);
196  setOperationAction(ISD::SRL_PARTS, MVT::i32, Expand);
197
198  // We don't have line number support yet.
199  setOperationAction(ISD::LOCATION, MVT::Other, Expand);
200  setOperationAction(ISD::DEBUG_LOC, MVT::Other, Expand);
201  setOperationAction(ISD::DEBUG_LABEL, MVT::Other, Expand);
202
203  // RET must be custom lowered, to meet ABI requirements
204  setOperationAction(ISD::RET               , MVT::Other, Custom);
205
206  // VASTART needs to be custom lowered to use the VarArgsFrameIndex
207  setOperationAction(ISD::VASTART           , MVT::Other, Custom);
208
209  // Use the default implementation.
210  setOperationAction(ISD::VAARG             , MVT::Other, Expand);
211  setOperationAction(ISD::VACOPY            , MVT::Other, Expand);
212  setOperationAction(ISD::VAEND             , MVT::Other, Expand);
213  setOperationAction(ISD::STACKSAVE         , MVT::Other, Expand);
214  setOperationAction(ISD::STACKRESTORE      , MVT::Other, Expand);
215  setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32  , Expand);
216
217  setOperationAction(ISD::ConstantFP, MVT::f64, Expand);
218  setOperationAction(ISD::ConstantFP, MVT::f32, Expand);
219
220  setStackPointerRegisterToSaveRestore(V8::O6);
221
222  if (TM.getSubtarget<SparcV8Subtarget>().isV9()) {
223    setOperationAction(ISD::CTPOP, MVT::i32, Legal);
224  }
225
226  computeRegisterProperties();
227}
228
229const char *SparcV8TargetLowering::getTargetNodeName(unsigned Opcode) const {
230  switch (Opcode) {
231  default: return 0;
232  case V8ISD::CMPICC:     return "V8ISD::CMPICC";
233  case V8ISD::CMPFCC:     return "V8ISD::CMPFCC";
234  case V8ISD::BRICC:      return "V8ISD::BRICC";
235  case V8ISD::BRFCC:      return "V8ISD::BRFCC";
236  case V8ISD::SELECT_ICC: return "V8ISD::SELECT_ICC";
237  case V8ISD::SELECT_FCC: return "V8ISD::SELECT_FCC";
238  case V8ISD::Hi:         return "V8ISD::Hi";
239  case V8ISD::Lo:         return "V8ISD::Lo";
240  case V8ISD::FTOI:       return "V8ISD::FTOI";
241  case V8ISD::ITOF:       return "V8ISD::ITOF";
242  case V8ISD::CALL:       return "V8ISD::CALL";
243  case V8ISD::RET_FLAG:   return "V8ISD::RET_FLAG";
244  }
245}
246
247/// isMaskedValueZeroForTargetNode - Return true if 'Op & Mask' is known to
248/// be zero. Op is expected to be a target specific node. Used by DAG
249/// combiner.
250bool SparcV8TargetLowering::
251isMaskedValueZeroForTargetNode(const SDOperand &Op, uint64_t Mask) const {
252  switch (Op.getOpcode()) {
253  default: return false;
254  case V8ISD::SELECT_ICC:
255  case V8ISD::SELECT_FCC:
256    assert(MVT::isInteger(Op.getValueType()) && "Not an integer select!");
257    // These operations are masked zero if both the left and the right are zero.
258    return MaskedValueIsZero(Op.getOperand(0), Mask) &&
259           MaskedValueIsZero(Op.getOperand(1), Mask);
260  }
261}
262
263
264/// LowerArguments - V8 uses a very simple ABI, where all values are passed in
265/// either one or two GPRs, including FP values.  TODO: we should pass FP values
266/// in FP registers for fastcc functions.
267std::vector<SDOperand>
268SparcV8TargetLowering::LowerArguments(Function &F, SelectionDAG &DAG) {
269  MachineFunction &MF = DAG.getMachineFunction();
270  SSARegMap *RegMap = MF.getSSARegMap();
271  std::vector<SDOperand> ArgValues;
272
273  static const unsigned ArgRegs[] = {
274    V8::I0, V8::I1, V8::I2, V8::I3, V8::I4, V8::I5
275  };
276
277  const unsigned *CurArgReg = ArgRegs, *ArgRegEnd = ArgRegs+6;
278  unsigned ArgOffset = 68;
279
280  SDOperand Root = DAG.getRoot();
281  std::vector<SDOperand> OutChains;
282
283  for (Function::arg_iterator I = F.arg_begin(), E = F.arg_end(); I != E; ++I) {
284    MVT::ValueType ObjectVT = getValueType(I->getType());
285
286    switch (ObjectVT) {
287    default: assert(0 && "Unhandled argument type!");
288    case MVT::i1:
289    case MVT::i8:
290    case MVT::i16:
291    case MVT::i32:
292      if (I->use_empty()) {                // Argument is dead.
293        if (CurArgReg < ArgRegEnd) ++CurArgReg;
294        ArgValues.push_back(DAG.getNode(ISD::UNDEF, ObjectVT));
295      } else if (CurArgReg < ArgRegEnd) {  // Lives in an incoming GPR
296        unsigned VReg = RegMap->createVirtualRegister(&V8::IntRegsRegClass);
297        MF.addLiveIn(*CurArgReg++, VReg);
298        SDOperand Arg = DAG.getCopyFromReg(Root, VReg, MVT::i32);
299        if (ObjectVT != MVT::i32) {
300          unsigned AssertOp = I->getType()->isSigned() ? ISD::AssertSext
301                                                       : ISD::AssertZext;
302          Arg = DAG.getNode(AssertOp, MVT::i32, Arg,
303                            DAG.getValueType(ObjectVT));
304          Arg = DAG.getNode(ISD::TRUNCATE, ObjectVT, Arg);
305        }
306        ArgValues.push_back(Arg);
307      } else {
308        int FrameIdx = MF.getFrameInfo()->CreateFixedObject(4, ArgOffset);
309        SDOperand FIPtr = DAG.getFrameIndex(FrameIdx, MVT::i32);
310        SDOperand Load;
311        if (ObjectVT == MVT::i32) {
312          Load = DAG.getLoad(MVT::i32, Root, FIPtr, DAG.getSrcValue(0));
313        } else {
314          unsigned LoadOp =
315            I->getType()->isSigned() ? ISD::SEXTLOAD : ISD::ZEXTLOAD;
316
317          // Sparc is big endian, so add an offset based on the ObjectVT.
318          unsigned Offset = 4-std::max(1U, MVT::getSizeInBits(ObjectVT)/8);
319          FIPtr = DAG.getNode(ISD::ADD, MVT::i32, FIPtr,
320                              DAG.getConstant(Offset, MVT::i32));
321          Load = DAG.getExtLoad(LoadOp, MVT::i32, Root, FIPtr,
322                                DAG.getSrcValue(0), ObjectVT);
323          Load = DAG.getNode(ISD::TRUNCATE, ObjectVT, Load);
324        }
325        ArgValues.push_back(Load);
326      }
327
328      ArgOffset += 4;
329      break;
330    case MVT::f32:
331      if (I->use_empty()) {                // Argument is dead.
332        if (CurArgReg < ArgRegEnd) ++CurArgReg;
333        ArgValues.push_back(DAG.getNode(ISD::UNDEF, ObjectVT));
334      } else if (CurArgReg < ArgRegEnd) {  // Lives in an incoming GPR
335        // FP value is passed in an integer register.
336        unsigned VReg = RegMap->createVirtualRegister(&V8::IntRegsRegClass);
337        MF.addLiveIn(*CurArgReg++, VReg);
338        SDOperand Arg = DAG.getCopyFromReg(Root, VReg, MVT::i32);
339
340        Arg = DAG.getNode(ISD::BIT_CONVERT, MVT::f32, Arg);
341        ArgValues.push_back(Arg);
342      } else {
343        int FrameIdx = MF.getFrameInfo()->CreateFixedObject(4, ArgOffset);
344        SDOperand FIPtr = DAG.getFrameIndex(FrameIdx, MVT::i32);
345        SDOperand Load = DAG.getLoad(MVT::f32, Root, FIPtr, DAG.getSrcValue(0));
346        ArgValues.push_back(Load);
347      }
348      ArgOffset += 4;
349      break;
350
351    case MVT::i64:
352    case MVT::f64:
353      if (I->use_empty()) {                // Argument is dead.
354        if (CurArgReg < ArgRegEnd) ++CurArgReg;
355        if (CurArgReg < ArgRegEnd) ++CurArgReg;
356        ArgValues.push_back(DAG.getNode(ISD::UNDEF, ObjectVT));
357      } else if (/* FIXME: Apparently this isn't safe?? */
358                 0 && CurArgReg == ArgRegEnd && ObjectVT == MVT::f64 &&
359                 ((CurArgReg-ArgRegs) & 1) == 0) {
360        // If this is a double argument and the whole thing lives on the stack,
361        // and the argument is aligned, load the double straight from the stack.
362        // We can't do a load in cases like void foo([6ints], int,double),
363        // because the double wouldn't be aligned!
364        int FrameIdx = MF.getFrameInfo()->CreateFixedObject(8, ArgOffset);
365        SDOperand FIPtr = DAG.getFrameIndex(FrameIdx, MVT::i32);
366        ArgValues.push_back(DAG.getLoad(MVT::f64, Root, FIPtr,
367                                        DAG.getSrcValue(0)));
368      } else {
369        SDOperand HiVal;
370        if (CurArgReg < ArgRegEnd) {  // Lives in an incoming GPR
371          unsigned VRegHi = RegMap->createVirtualRegister(&V8::IntRegsRegClass);
372          MF.addLiveIn(*CurArgReg++, VRegHi);
373          HiVal = DAG.getCopyFromReg(Root, VRegHi, MVT::i32);
374        } else {
375          int FrameIdx = MF.getFrameInfo()->CreateFixedObject(4, ArgOffset);
376          SDOperand FIPtr = DAG.getFrameIndex(FrameIdx, MVT::i32);
377          HiVal = DAG.getLoad(MVT::i32, Root, FIPtr, DAG.getSrcValue(0));
378        }
379
380        SDOperand LoVal;
381        if (CurArgReg < ArgRegEnd) {  // Lives in an incoming GPR
382          unsigned VRegLo = RegMap->createVirtualRegister(&V8::IntRegsRegClass);
383          MF.addLiveIn(*CurArgReg++, VRegLo);
384          LoVal = DAG.getCopyFromReg(Root, VRegLo, MVT::i32);
385        } else {
386          int FrameIdx = MF.getFrameInfo()->CreateFixedObject(4, ArgOffset+4);
387          SDOperand FIPtr = DAG.getFrameIndex(FrameIdx, MVT::i32);
388          LoVal = DAG.getLoad(MVT::i32, Root, FIPtr, DAG.getSrcValue(0));
389        }
390
391        // Compose the two halves together into an i64 unit.
392        SDOperand WholeValue =
393          DAG.getNode(ISD::BUILD_PAIR, MVT::i64, LoVal, HiVal);
394
395        // If we want a double, do a bit convert.
396        if (ObjectVT == MVT::f64)
397          WholeValue = DAG.getNode(ISD::BIT_CONVERT, MVT::f64, WholeValue);
398
399        ArgValues.push_back(WholeValue);
400      }
401      ArgOffset += 8;
402      break;
403    }
404  }
405
406  // Store remaining ArgRegs to the stack if this is a varargs function.
407  if (F.getFunctionType()->isVarArg()) {
408    // Remember the vararg offset for the va_start implementation.
409    VarArgsFrameOffset = ArgOffset;
410
411    for (; CurArgReg != ArgRegEnd; ++CurArgReg) {
412      unsigned VReg = RegMap->createVirtualRegister(&V8::IntRegsRegClass);
413      MF.addLiveIn(*CurArgReg, VReg);
414      SDOperand Arg = DAG.getCopyFromReg(DAG.getRoot(), VReg, MVT::i32);
415
416      int FrameIdx = MF.getFrameInfo()->CreateFixedObject(4, ArgOffset);
417      SDOperand FIPtr = DAG.getFrameIndex(FrameIdx, MVT::i32);
418
419      OutChains.push_back(DAG.getNode(ISD::STORE, MVT::Other, DAG.getRoot(),
420                                      Arg, FIPtr, DAG.getSrcValue(0)));
421      ArgOffset += 4;
422    }
423  }
424
425  if (!OutChains.empty())
426    DAG.setRoot(DAG.getNode(ISD::TokenFactor, MVT::Other, OutChains));
427
428  // Finally, inform the code generator which regs we return values in.
429  switch (getValueType(F.getReturnType())) {
430  default: assert(0 && "Unknown type!");
431  case MVT::isVoid: break;
432  case MVT::i1:
433  case MVT::i8:
434  case MVT::i16:
435  case MVT::i32:
436    MF.addLiveOut(V8::I0);
437    break;
438  case MVT::i64:
439    MF.addLiveOut(V8::I0);
440    MF.addLiveOut(V8::I1);
441    break;
442  case MVT::f32:
443    MF.addLiveOut(V8::F0);
444    break;
445  case MVT::f64:
446    MF.addLiveOut(V8::D0);
447    break;
448  }
449
450  return ArgValues;
451}
452
453std::pair<SDOperand, SDOperand>
454SparcV8TargetLowering::LowerCallTo(SDOperand Chain, const Type *RetTy,
455                                   bool isVarArg, unsigned CC,
456                                   bool isTailCall, SDOperand Callee,
457                                   ArgListTy &Args, SelectionDAG &DAG) {
458  MachineFunction &MF = DAG.getMachineFunction();
459  // Count the size of the outgoing arguments.
460  unsigned ArgsSize = 0;
461  for (unsigned i = 0, e = Args.size(); i != e; ++i) {
462    switch (getValueType(Args[i].second)) {
463    default: assert(0 && "Unknown value type!");
464    case MVT::i1:
465    case MVT::i8:
466    case MVT::i16:
467    case MVT::i32:
468    case MVT::f32:
469      ArgsSize += 4;
470      break;
471    case MVT::i64:
472    case MVT::f64:
473      ArgsSize += 8;
474      break;
475    }
476  }
477  if (ArgsSize > 4*6)
478    ArgsSize -= 4*6;    // Space for first 6 arguments is prereserved.
479  else
480    ArgsSize = 0;
481
482  // Keep stack frames 8-byte aligned.
483  ArgsSize = (ArgsSize+7) & ~7;
484
485  Chain = DAG.getNode(ISD::CALLSEQ_START, MVT::Other, Chain,
486                      DAG.getConstant(ArgsSize, getPointerTy()));
487
488  SDOperand StackPtr, NullSV;
489  std::vector<SDOperand> Stores;
490  std::vector<SDOperand> RegValuesToPass;
491  unsigned ArgOffset = 68;
492  for (unsigned i = 0, e = Args.size(); i != e; ++i) {
493    SDOperand Val = Args[i].first;
494    MVT::ValueType ObjectVT = Val.getValueType();
495    SDOperand ValToStore(0, 0);
496    unsigned ObjSize;
497    switch (ObjectVT) {
498    default: assert(0 && "Unhandled argument type!");
499    case MVT::i1:
500    case MVT::i8:
501    case MVT::i16:
502      // Promote the integer to 32-bits.  If the input type is signed, use a
503      // sign extend, otherwise use a zero extend.
504      if (Args[i].second->isSigned())
505        Val = DAG.getNode(ISD::SIGN_EXTEND, MVT::i32, Val);
506      else
507        Val = DAG.getNode(ISD::ZERO_EXTEND, MVT::i32, Val);
508      // FALL THROUGH
509    case MVT::i32:
510      ObjSize = 4;
511
512      if (RegValuesToPass.size() >= 6) {
513        ValToStore = Val;
514      } else {
515        RegValuesToPass.push_back(Val);
516      }
517      break;
518    case MVT::f32:
519      ObjSize = 4;
520      if (RegValuesToPass.size() >= 6) {
521        ValToStore = Val;
522      } else {
523        // Convert this to a FP value in an int reg.
524        Val = DAG.getNode(ISD::BIT_CONVERT, MVT::i32, Val);
525        RegValuesToPass.push_back(Val);
526      }
527      break;
528    case MVT::f64:
529      ObjSize = 8;
530      // If we can store this directly into the outgoing slot, do so.  We can
531      // do this when all ArgRegs are used and if the outgoing slot is aligned.
532      // FIXME: McGill/misr fails with this.
533      if (0 && RegValuesToPass.size() >= 6 && ((ArgOffset-68) & 7) == 0) {
534        ValToStore = Val;
535        break;
536      }
537
538      // Otherwise, convert this to a FP value in int regs.
539      Val = DAG.getNode(ISD::BIT_CONVERT, MVT::i64, Val);
540      // FALL THROUGH
541    case MVT::i64:
542      ObjSize = 8;
543      if (RegValuesToPass.size() >= 6) {
544        ValToStore = Val;    // Whole thing is passed in memory.
545        break;
546      }
547
548      // Split the value into top and bottom part.  Top part goes in a reg.
549      SDOperand Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, MVT::i32, Val,
550                                 DAG.getConstant(1, MVT::i32));
551      SDOperand Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, MVT::i32, Val,
552                                 DAG.getConstant(0, MVT::i32));
553      RegValuesToPass.push_back(Hi);
554
555      if (RegValuesToPass.size() >= 6) {
556        ValToStore = Lo;
557        ArgOffset += 4;
558        ObjSize = 4;
559      } else {
560        RegValuesToPass.push_back(Lo);
561      }
562      break;
563    }
564
565    if (ValToStore.Val) {
566      if (!StackPtr.Val) {
567        StackPtr = DAG.getRegister(V8::O6, MVT::i32);
568        NullSV = DAG.getSrcValue(NULL);
569      }
570      SDOperand PtrOff = DAG.getConstant(ArgOffset, getPointerTy());
571      PtrOff = DAG.getNode(ISD::ADD, MVT::i32, StackPtr, PtrOff);
572      Stores.push_back(DAG.getNode(ISD::STORE, MVT::Other, Chain,
573                                   ValToStore, PtrOff, NullSV));
574    }
575    ArgOffset += ObjSize;
576  }
577
578  // Emit all stores, make sure the occur before any copies into physregs.
579  if (!Stores.empty())
580    Chain = DAG.getNode(ISD::TokenFactor, MVT::Other, Stores);
581
582  static const unsigned ArgRegs[] = {
583    V8::O0, V8::O1, V8::O2, V8::O3, V8::O4, V8::O5
584  };
585
586  // Build a sequence of copy-to-reg nodes chained together with token chain
587  // and flag operands which copy the outgoing args into O[0-5].
588  SDOperand InFlag;
589  for (unsigned i = 0, e = RegValuesToPass.size(); i != e; ++i) {
590    Chain = DAG.getCopyToReg(Chain, ArgRegs[i], RegValuesToPass[i], InFlag);
591    InFlag = Chain.getValue(1);
592  }
593
594  // If the callee is a GlobalAddress node (quite common, every direct call is)
595  // turn it into a TargetGlobalAddress node so that legalize doesn't hack it.
596  if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee))
597    Callee = DAG.getTargetGlobalAddress(G->getGlobal(), MVT::i32);
598
599  std::vector<MVT::ValueType> NodeTys;
600  NodeTys.push_back(MVT::Other);   // Returns a chain
601  NodeTys.push_back(MVT::Flag);    // Returns a flag for retval copy to use.
602  std::vector<SDOperand> Ops;
603  Ops.push_back(Chain);
604  Ops.push_back(Callee);
605  if (InFlag.Val)
606    Ops.push_back(InFlag);
607  Chain = DAG.getNode(V8ISD::CALL, NodeTys, Ops);
608  InFlag = Chain.getValue(1);
609
610  MVT::ValueType RetTyVT = getValueType(RetTy);
611  SDOperand RetVal;
612  if (RetTyVT != MVT::isVoid) {
613    switch (RetTyVT) {
614    default: assert(0 && "Unknown value type to return!");
615    case MVT::i1:
616    case MVT::i8:
617    case MVT::i16:
618      RetVal = DAG.getCopyFromReg(Chain, V8::O0, MVT::i32, InFlag);
619      Chain = RetVal.getValue(1);
620
621      // Add a note to keep track of whether it is sign or zero extended.
622      RetVal = DAG.getNode(RetTy->isSigned() ? ISD::AssertSext :ISD::AssertZext,
623                           MVT::i32, RetVal, DAG.getValueType(RetTyVT));
624      RetVal = DAG.getNode(ISD::TRUNCATE, RetTyVT, RetVal);
625      break;
626    case MVT::i32:
627      RetVal = DAG.getCopyFromReg(Chain, V8::O0, MVT::i32, InFlag);
628      Chain = RetVal.getValue(1);
629      break;
630    case MVT::f32:
631      RetVal = DAG.getCopyFromReg(Chain, V8::F0, MVT::f32, InFlag);
632      Chain = RetVal.getValue(1);
633      break;
634    case MVT::f64:
635      RetVal = DAG.getCopyFromReg(Chain, V8::D0, MVT::f64, InFlag);
636      Chain = RetVal.getValue(1);
637      break;
638    case MVT::i64:
639      SDOperand Lo = DAG.getCopyFromReg(Chain, V8::O1, MVT::i32, InFlag);
640      SDOperand Hi = DAG.getCopyFromReg(Lo.getValue(1), V8::O0, MVT::i32,
641                                        Lo.getValue(2));
642      RetVal = DAG.getNode(ISD::BUILD_PAIR, MVT::i64, Lo, Hi);
643      Chain = Hi.getValue(1);
644      break;
645    }
646  }
647
648  Chain = DAG.getNode(ISD::CALLSEQ_END, MVT::Other, Chain,
649                      DAG.getConstant(ArgsSize, getPointerTy()));
650
651  return std::make_pair(RetVal, Chain);
652}
653
654std::pair<SDOperand, SDOperand> SparcV8TargetLowering::
655LowerFrameReturnAddress(bool isFrameAddr, SDOperand Chain, unsigned Depth,
656                        SelectionDAG &DAG) {
657  assert(0 && "Unimp");
658  abort();
659}
660
661// Look at LHS/RHS/CC and see if they are a lowered V8 setcc instruction.  If so
662// set LHS/RHS and V8CC to the LHS/RHS of the setcc and V8CC to the condition.
663static void LookThroughSetCC(SDOperand &LHS, SDOperand &RHS,
664                             ISD::CondCode CC, unsigned &V8CC) {
665  if (isa<ConstantSDNode>(RHS) && cast<ConstantSDNode>(RHS)->getValue() == 0 &&
666      CC == ISD::SETNE &&
667      ((LHS.getOpcode() == V8ISD::SELECT_ICC &&
668        LHS.getOperand(3).getOpcode() == V8ISD::CMPICC) ||
669       (LHS.getOpcode() == V8ISD::SELECT_FCC &&
670        LHS.getOperand(3).getOpcode() == V8ISD::CMPFCC)) &&
671      isa<ConstantSDNode>(LHS.getOperand(0)) &&
672      isa<ConstantSDNode>(LHS.getOperand(1)) &&
673      cast<ConstantSDNode>(LHS.getOperand(0))->getValue() == 1 &&
674      cast<ConstantSDNode>(LHS.getOperand(1))->getValue() == 0) {
675    SDOperand CMPCC = LHS.getOperand(3);
676    V8CC = cast<ConstantSDNode>(LHS.getOperand(2))->getValue();
677    LHS = CMPCC.getOperand(0);
678    RHS = CMPCC.getOperand(1);
679  }
680}
681
682
683SDOperand SparcV8TargetLowering::
684LowerOperation(SDOperand Op, SelectionDAG &DAG) {
685  switch (Op.getOpcode()) {
686  default: assert(0 && "Should not custom lower this!");
687  case ISD::GlobalAddress: {
688    GlobalValue *GV = cast<GlobalAddressSDNode>(Op)->getGlobal();
689    SDOperand GA = DAG.getTargetGlobalAddress(GV, MVT::i32);
690    SDOperand Hi = DAG.getNode(V8ISD::Hi, MVT::i32, GA);
691    SDOperand Lo = DAG.getNode(V8ISD::Lo, MVT::i32, GA);
692    return DAG.getNode(ISD::ADD, MVT::i32, Lo, Hi);
693  }
694  case ISD::ConstantPool: {
695    Constant *C = cast<ConstantPoolSDNode>(Op)->get();
696    SDOperand CP = DAG.getTargetConstantPool(C, MVT::i32);
697    SDOperand Hi = DAG.getNode(V8ISD::Hi, MVT::i32, CP);
698    SDOperand Lo = DAG.getNode(V8ISD::Lo, MVT::i32, CP);
699    return DAG.getNode(ISD::ADD, MVT::i32, Lo, Hi);
700  }
701  case ISD::FP_TO_SINT:
702    // Convert the fp value to integer in an FP register.
703    assert(Op.getValueType() == MVT::i32);
704    Op = DAG.getNode(V8ISD::FTOI, MVT::f32, Op.getOperand(0));
705    return DAG.getNode(ISD::BIT_CONVERT, MVT::i32, Op);
706  case ISD::SINT_TO_FP: {
707    assert(Op.getOperand(0).getValueType() == MVT::i32);
708    SDOperand Tmp = DAG.getNode(ISD::BIT_CONVERT, MVT::f32, Op.getOperand(0));
709    // Convert the int value to FP in an FP register.
710    return DAG.getNode(V8ISD::ITOF, Op.getValueType(), Tmp);
711  }
712  case ISD::BR_CC: {
713    SDOperand Chain = Op.getOperand(0);
714    ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(1))->get();
715    SDOperand LHS = Op.getOperand(2);
716    SDOperand RHS = Op.getOperand(3);
717    SDOperand Dest = Op.getOperand(4);
718    unsigned Opc, V8CC = ~0U;
719
720    // If this is a br_cc of a "setcc", and if the setcc got lowered into
721    // an CMP[IF]CC/SELECT_[IF]CC pair, find the original compared values.
722    LookThroughSetCC(LHS, RHS, CC, V8CC);
723
724    // Get the condition flag.
725    SDOperand CompareFlag;
726    if (LHS.getValueType() == MVT::i32) {
727      std::vector<MVT::ValueType> VTs;
728      VTs.push_back(MVT::i32);
729      VTs.push_back(MVT::Flag);
730      std::vector<SDOperand> Ops;
731      Ops.push_back(LHS);
732      Ops.push_back(RHS);
733      CompareFlag = DAG.getNode(V8ISD::CMPICC, VTs, Ops).getValue(1);
734      if (V8CC == ~0U) V8CC = IntCondCCodeToICC(CC);
735      Opc = V8ISD::BRICC;
736    } else {
737      CompareFlag = DAG.getNode(V8ISD::CMPFCC, MVT::Flag, LHS, RHS);
738      if (V8CC == ~0U) V8CC = FPCondCCodeToFCC(CC);
739      Opc = V8ISD::BRFCC;
740    }
741    return DAG.getNode(Opc, MVT::Other, Chain, Dest,
742                       DAG.getConstant(V8CC, MVT::i32), CompareFlag);
743  }
744  case ISD::SELECT_CC: {
745    SDOperand LHS = Op.getOperand(0);
746    SDOperand RHS = Op.getOperand(1);
747    ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(4))->get();
748    SDOperand TrueVal = Op.getOperand(2);
749    SDOperand FalseVal = Op.getOperand(3);
750    unsigned Opc, V8CC = ~0U;
751
752    // If this is a select_cc of a "setcc", and if the setcc got lowered into
753    // an CMP[IF]CC/SELECT_[IF]CC pair, find the original compared values.
754    LookThroughSetCC(LHS, RHS, CC, V8CC);
755
756    SDOperand CompareFlag;
757    if (LHS.getValueType() == MVT::i32) {
758      std::vector<MVT::ValueType> VTs;
759      VTs.push_back(LHS.getValueType());   // subcc returns a value
760      VTs.push_back(MVT::Flag);
761      std::vector<SDOperand> Ops;
762      Ops.push_back(LHS);
763      Ops.push_back(RHS);
764      CompareFlag = DAG.getNode(V8ISD::CMPICC, VTs, Ops).getValue(1);
765      Opc = V8ISD::SELECT_ICC;
766      if (V8CC == ~0U) V8CC = IntCondCCodeToICC(CC);
767    } else {
768      CompareFlag = DAG.getNode(V8ISD::CMPFCC, MVT::Flag, LHS, RHS);
769      Opc = V8ISD::SELECT_FCC;
770      if (V8CC == ~0U) V8CC = FPCondCCodeToFCC(CC);
771    }
772    return DAG.getNode(Opc, TrueVal.getValueType(), TrueVal, FalseVal,
773                       DAG.getConstant(V8CC, MVT::i32), CompareFlag);
774  }
775  case ISD::VASTART: {
776    // vastart just stores the address of the VarArgsFrameIndex slot into the
777    // memory location argument.
778    SDOperand Offset = DAG.getNode(ISD::ADD, MVT::i32,
779                                   DAG.getRegister(V8::I6, MVT::i32),
780                                   DAG.getConstant(VarArgsFrameOffset, MVT::i32));
781    return DAG.getNode(ISD::STORE, MVT::Other, Op.getOperand(0), Offset,
782                       Op.getOperand(1), Op.getOperand(2));
783  }
784  case ISD::RET: {
785    SDOperand Copy;
786
787    switch(Op.getNumOperands()) {
788    default:
789      assert(0 && "Do not know how to return this many arguments!");
790      abort();
791    case 1:
792      return SDOperand(); // ret void is legal
793    case 2: {
794      unsigned ArgReg;
795      switch(Op.getOperand(1).getValueType()) {
796      default: assert(0 && "Unknown type to return!");
797      case MVT::i32: ArgReg = V8::I0; break;
798      case MVT::f32: ArgReg = V8::F0; break;
799      case MVT::f64: ArgReg = V8::D0; break;
800      }
801      Copy = DAG.getCopyToReg(Op.getOperand(0), ArgReg, Op.getOperand(1),
802                              SDOperand());
803      break;
804    }
805    case 3:
806      Copy = DAG.getCopyToReg(Op.getOperand(0), V8::I0, Op.getOperand(2),
807                              SDOperand());
808      Copy = DAG.getCopyToReg(Copy, V8::I1, Op.getOperand(1), Copy.getValue(1));
809      break;
810    }
811    return DAG.getNode(V8ISD::RET_FLAG, MVT::Other, Copy, Copy.getValue(1));
812  }
813  }
814}
815
816MachineBasicBlock *
817SparcV8TargetLowering::InsertAtEndOfBasicBlock(MachineInstr *MI,
818                                               MachineBasicBlock *BB) {
819  unsigned BROpcode;
820  unsigned CC;
821  // Figure out the conditional branch opcode to use for this select_cc.
822  switch (MI->getOpcode()) {
823  default: assert(0 && "Unknown SELECT_CC!");
824  case V8::SELECT_CC_Int_ICC:
825  case V8::SELECT_CC_FP_ICC:
826  case V8::SELECT_CC_DFP_ICC:
827    BROpcode = V8::BCOND;
828  case V8::SELECT_CC_Int_FCC:
829  case V8::SELECT_CC_FP_FCC:
830  case V8::SELECT_CC_DFP_FCC:
831    BROpcode = V8::FBCOND;
832    break;
833  }
834
835  CC = (V8CC::CondCodes)MI->getOperand(3).getImmedValue();
836
837  // To "insert" a SELECT_CC instruction, we actually have to insert the diamond
838  // control-flow pattern.  The incoming instruction knows the destination vreg
839  // to set, the condition code register to branch on, the true/false values to
840  // select between, and a branch opcode to use.
841  const BasicBlock *LLVM_BB = BB->getBasicBlock();
842  ilist<MachineBasicBlock>::iterator It = BB;
843  ++It;
844
845  //  thisMBB:
846  //  ...
847  //   TrueVal = ...
848  //   [f]bCC copy1MBB
849  //   fallthrough --> copy0MBB
850  MachineBasicBlock *thisMBB = BB;
851  MachineBasicBlock *copy0MBB = new MachineBasicBlock(LLVM_BB);
852  MachineBasicBlock *sinkMBB = new MachineBasicBlock(LLVM_BB);
853  BuildMI(BB, BROpcode, 2).addMBB(sinkMBB).addImm(CC);
854  MachineFunction *F = BB->getParent();
855  F->getBasicBlockList().insert(It, copy0MBB);
856  F->getBasicBlockList().insert(It, sinkMBB);
857  // Update machine-CFG edges
858  BB->addSuccessor(copy0MBB);
859  BB->addSuccessor(sinkMBB);
860
861  //  copy0MBB:
862  //   %FalseValue = ...
863  //   # fallthrough to sinkMBB
864  BB = copy0MBB;
865
866  // Update machine-CFG edges
867  BB->addSuccessor(sinkMBB);
868
869  //  sinkMBB:
870  //   %Result = phi [ %FalseValue, copy0MBB ], [ %TrueValue, thisMBB ]
871  //  ...
872  BB = sinkMBB;
873  BuildMI(BB, V8::PHI, 4, MI->getOperand(0).getReg())
874    .addReg(MI->getOperand(2).getReg()).addMBB(copy0MBB)
875    .addReg(MI->getOperand(1).getReg()).addMBB(thisMBB);
876
877  delete MI;   // The pseudo instruction is gone now.
878  return BB;
879}
880
881//===----------------------------------------------------------------------===//
882// Instruction Selector Implementation
883//===----------------------------------------------------------------------===//
884
885//===--------------------------------------------------------------------===//
886/// SparcV8DAGToDAGISel - SPARC specific code to select Sparc V8 machine
887/// instructions for SelectionDAG operations.
888///
889namespace {
890class SparcV8DAGToDAGISel : public SelectionDAGISel {
891  SparcV8TargetLowering V8Lowering;
892
893  /// Subtarget - Keep a pointer to the Sparc Subtarget around so that we can
894  /// make the right decision when generating code for different targets.
895  const SparcV8Subtarget &Subtarget;
896public:
897  SparcV8DAGToDAGISel(TargetMachine &TM)
898    : SelectionDAGISel(V8Lowering), V8Lowering(TM),
899      Subtarget(TM.getSubtarget<SparcV8Subtarget>()) {
900  }
901
902  SDOperand Select(SDOperand Op);
903
904  // Complex Pattern Selectors.
905  bool SelectADDRrr(SDOperand N, SDOperand &R1, SDOperand &R2);
906  bool SelectADDRri(SDOperand N, SDOperand &Base, SDOperand &Offset);
907
908  /// InstructionSelectBasicBlock - This callback is invoked by
909  /// SelectionDAGISel when it has created a SelectionDAG for us to codegen.
910  virtual void InstructionSelectBasicBlock(SelectionDAG &DAG);
911
912  virtual const char *getPassName() const {
913    return "SparcV8 DAG->DAG Pattern Instruction Selection";
914  }
915
916  // Include the pieces autogenerated from the target description.
917#include "SparcV8GenDAGISel.inc"
918};
919}  // end anonymous namespace
920
921/// InstructionSelectBasicBlock - This callback is invoked by
922/// SelectionDAGISel when it has created a SelectionDAG for us to codegen.
923void SparcV8DAGToDAGISel::InstructionSelectBasicBlock(SelectionDAG &DAG) {
924  DEBUG(BB->dump());
925
926  // Select target instructions for the DAG.
927  DAG.setRoot(Select(DAG.getRoot()));
928  CodeGenMap.clear();
929  DAG.RemoveDeadNodes();
930
931  // Emit machine code to BB.
932  ScheduleAndEmitDAG(DAG);
933}
934
935bool SparcV8DAGToDAGISel::SelectADDRri(SDOperand Addr, SDOperand &Base,
936                                       SDOperand &Offset) {
937  if (FrameIndexSDNode *FIN = dyn_cast<FrameIndexSDNode>(Addr)) {
938    Base = CurDAG->getTargetFrameIndex(FIN->getIndex(), MVT::i32);
939    Offset = CurDAG->getTargetConstant(0, MVT::i32);
940    return true;
941  }
942
943  if (Addr.getOpcode() == ISD::ADD) {
944    if (ConstantSDNode *CN = dyn_cast<ConstantSDNode>(Addr.getOperand(1))) {
945      if (Predicate_simm13(CN)) {
946        if (FrameIndexSDNode *FIN =
947                dyn_cast<FrameIndexSDNode>(Addr.getOperand(0))) {
948          // Constant offset from frame ref.
949          Base = CurDAG->getTargetFrameIndex(FIN->getIndex(), MVT::i32);
950        } else {
951          Base = Select(Addr.getOperand(0));
952        }
953        Offset = CurDAG->getTargetConstant(CN->getValue(), MVT::i32);
954        return true;
955      }
956    }
957    if (Addr.getOperand(0).getOpcode() == V8ISD::Lo) {
958      Base = Select(Addr.getOperand(1));
959      Offset = Addr.getOperand(0).getOperand(0);
960      return true;
961    }
962    if (Addr.getOperand(1).getOpcode() == V8ISD::Lo) {
963      Base = Select(Addr.getOperand(0));
964      Offset = Addr.getOperand(1).getOperand(0);
965      return true;
966    }
967  }
968  Base = Select(Addr);
969  Offset = CurDAG->getTargetConstant(0, MVT::i32);
970  return true;
971}
972
973bool SparcV8DAGToDAGISel::SelectADDRrr(SDOperand Addr, SDOperand &R1,
974                                       SDOperand &R2) {
975  if (Addr.getOpcode() == ISD::FrameIndex) return false;
976  if (Addr.getOpcode() == ISD::ADD) {
977    if (isa<ConstantSDNode>(Addr.getOperand(1)) &&
978        Predicate_simm13(Addr.getOperand(1).Val))
979      return false;  // Let the reg+imm pattern catch this!
980    if (Addr.getOperand(0).getOpcode() == V8ISD::Lo ||
981        Addr.getOperand(1).getOpcode() == V8ISD::Lo)
982      return false;  // Let the reg+imm pattern catch this!
983    R1 = Select(Addr.getOperand(0));
984    R2 = Select(Addr.getOperand(1));
985    return true;
986  }
987
988  R1 = Select(Addr);
989  R2 = CurDAG->getRegister(V8::G0, MVT::i32);
990  return true;
991}
992
993SDOperand SparcV8DAGToDAGISel::Select(SDOperand Op) {
994  SDNode *N = Op.Val;
995  if (N->getOpcode() >= ISD::BUILTIN_OP_END &&
996      N->getOpcode() < V8ISD::FIRST_NUMBER)
997    return Op;   // Already selected.
998                 // If this has already been converted, use it.
999  std::map<SDOperand, SDOperand>::iterator CGMI = CodeGenMap.find(Op);
1000  if (CGMI != CodeGenMap.end()) return CGMI->second;
1001
1002  switch (N->getOpcode()) {
1003  default: break;
1004  case ISD::FrameIndex: {
1005    int FI = cast<FrameIndexSDNode>(N)->getIndex();
1006    if (N->hasOneUse())
1007      return CurDAG->SelectNodeTo(N, V8::ADDri, MVT::i32,
1008                                  CurDAG->getTargetFrameIndex(FI, MVT::i32),
1009                                  CurDAG->getTargetConstant(0, MVT::i32));
1010    return CodeGenMap[Op] =
1011      CurDAG->getTargetNode(V8::ADDri, MVT::i32,
1012                            CurDAG->getTargetFrameIndex(FI, MVT::i32),
1013                            CurDAG->getTargetConstant(0, MVT::i32));
1014  }
1015  case ISD::ADD_PARTS: {
1016    SDOperand LHSL = Select(N->getOperand(0));
1017    SDOperand LHSH = Select(N->getOperand(1));
1018    SDOperand RHSL = Select(N->getOperand(2));
1019    SDOperand RHSH = Select(N->getOperand(3));
1020    // FIXME, handle immediate RHS.
1021    SDOperand Low = CurDAG->getTargetNode(V8::ADDCCrr, MVT::i32, MVT::Flag,
1022                                          LHSL, RHSL);
1023    SDOperand Hi  = CurDAG->getTargetNode(V8::ADDXrr, MVT::i32, LHSH, RHSH,
1024                                          Low.getValue(1));
1025    CodeGenMap[SDOperand(N, 0)] = Low;
1026    CodeGenMap[SDOperand(N, 1)] = Hi;
1027    return Op.ResNo ? Hi : Low;
1028  }
1029  case ISD::SUB_PARTS: {
1030    SDOperand LHSL = Select(N->getOperand(0));
1031    SDOperand LHSH = Select(N->getOperand(1));
1032    SDOperand RHSL = Select(N->getOperand(2));
1033    SDOperand RHSH = Select(N->getOperand(3));
1034    // FIXME, handle immediate RHS.
1035    SDOperand Low = CurDAG->getTargetNode(V8::SUBCCrr, MVT::i32, MVT::Flag,
1036                                          LHSL, RHSL);
1037    SDOperand Hi  = CurDAG->getTargetNode(V8::SUBXrr, MVT::i32, LHSH, RHSH,
1038                                          Low.getValue(1));
1039    CodeGenMap[SDOperand(N, 0)] = Low;
1040    CodeGenMap[SDOperand(N, 1)] = Hi;
1041    return Op.ResNo ? Hi : Low;
1042  }
1043  case ISD::SDIV:
1044  case ISD::UDIV: {
1045    // FIXME: should use a custom expander to expose the SRA to the dag.
1046    SDOperand DivLHS = Select(N->getOperand(0));
1047    SDOperand DivRHS = Select(N->getOperand(1));
1048
1049    // Set the Y register to the high-part.
1050    SDOperand TopPart;
1051    if (N->getOpcode() == ISD::SDIV) {
1052      TopPart = CurDAG->getTargetNode(V8::SRAri, MVT::i32, DivLHS,
1053                                      CurDAG->getTargetConstant(31, MVT::i32));
1054    } else {
1055      TopPart = CurDAG->getRegister(V8::G0, MVT::i32);
1056    }
1057    TopPart = CurDAG->getTargetNode(V8::WRYrr, MVT::Flag, TopPart,
1058                                    CurDAG->getRegister(V8::G0, MVT::i32));
1059
1060    // FIXME: Handle div by immediate.
1061    unsigned Opcode = N->getOpcode() == ISD::SDIV ? V8::SDIVrr : V8::UDIVrr;
1062    return CurDAG->SelectNodeTo(N, Opcode, MVT::i32, DivLHS, DivRHS, TopPart);
1063  }
1064  case ISD::MULHU:
1065  case ISD::MULHS: {
1066    // FIXME: Handle mul by immediate.
1067    SDOperand MulLHS = Select(N->getOperand(0));
1068    SDOperand MulRHS = Select(N->getOperand(1));
1069    unsigned Opcode = N->getOpcode() == ISD::MULHU ? V8::UMULrr : V8::SMULrr;
1070    SDOperand Mul = CurDAG->getTargetNode(Opcode, MVT::i32, MVT::Flag,
1071                                          MulLHS, MulRHS);
1072    // The high part is in the Y register.
1073    return CurDAG->SelectNodeTo(N, V8::RDY, MVT::i32, Mul.getValue(1));
1074  }
1075  case V8ISD::CALL:
1076    // FIXME: This is a workaround for a bug in tblgen.
1077  { // Pattern #47: (call:Flag (tglobaladdr:i32):$dst, ICC:Flag)
1078    // Emits: (CALL:void (tglobaladdr:i32):$dst)
1079    // Pattern complexity = 2  cost = 1
1080    SDOperand N1 = N->getOperand(1);
1081    if (N1.getOpcode() != ISD::TargetGlobalAddress &&
1082        N1.getOpcode() != ISD::ExternalSymbol) goto P47Fail;
1083    SDOperand InFlag = SDOperand(0, 0);
1084    SDOperand Chain = N->getOperand(0);
1085    SDOperand Tmp0 = N1;
1086    Chain = Select(Chain);
1087    SDOperand Result;
1088    if (N->getNumOperands() == 3) {
1089      InFlag = Select(N->getOperand(2));
1090      Result = CurDAG->getTargetNode(V8::CALL, MVT::Other, MVT::Flag, Tmp0,
1091                                     Chain, InFlag);
1092    } else {
1093      Result = CurDAG->getTargetNode(V8::CALL, MVT::Other, MVT::Flag, Tmp0,
1094                                     Chain);
1095    }
1096    Chain = CodeGenMap[SDOperand(N, 0)] = Result.getValue(0);
1097     CodeGenMap[SDOperand(N, 1)] = Result.getValue(1);
1098    return Result.getValue(Op.ResNo);
1099  }
1100    P47Fail:;
1101
1102  }
1103
1104  return SelectCode(Op);
1105}
1106
1107
1108/// createSparcV8ISelDag - This pass converts a legalized DAG into a
1109/// SPARC-specific DAG, ready for instruction scheduling.
1110///
1111FunctionPass *llvm::createSparcV8ISelDag(TargetMachine &TM) {
1112  return new SparcV8DAGToDAGISel(TM);
1113}
1114