MipsISelLowering.cpp revision 70a07c7fc437045a2421d279a99b19981f08acc2
1//===-- MipsISelLowering.cpp - Mips 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 defines the interfaces that Mips uses to lower LLVM code into a
11// selection DAG.
12//
13//===----------------------------------------------------------------------===//
14
15#define DEBUG_TYPE "mips-lower"
16#include "MipsISelLowering.h"
17#include "MipsMachineFunction.h"
18#include "MipsTargetMachine.h"
19#include "MipsTargetObjectFile.h"
20#include "MipsSubtarget.h"
21#include "InstPrinter/MipsInstPrinter.h"
22#include "MCTargetDesc/MipsBaseInfo.h"
23#include "llvm/DerivedTypes.h"
24#include "llvm/Function.h"
25#include "llvm/GlobalVariable.h"
26#include "llvm/Intrinsics.h"
27#include "llvm/CallingConv.h"
28#include "llvm/CodeGen/CallingConvLower.h"
29#include "llvm/CodeGen/MachineFrameInfo.h"
30#include "llvm/CodeGen/MachineFunction.h"
31#include "llvm/CodeGen/MachineInstrBuilder.h"
32#include "llvm/CodeGen/MachineRegisterInfo.h"
33#include "llvm/CodeGen/SelectionDAGISel.h"
34#include "llvm/CodeGen/ValueTypes.h"
35#include "llvm/Support/Debug.h"
36#include "llvm/Support/ErrorHandling.h"
37#include "llvm/Support/raw_ostream.h"
38
39using namespace llvm;
40
41// If I is a shifted mask, set the size (Size) and the first bit of the
42// mask (Pos), and return true.
43// For example, if I is 0x003ff800, (Pos, Size) = (11, 11).
44static bool IsShiftedMask(uint64_t I, uint64_t &Pos, uint64_t &Size) {
45  if (!isShiftedMask_64(I))
46     return false;
47
48  Size = CountPopulation_64(I);
49  Pos = CountTrailingZeros_64(I);
50  return true;
51}
52
53static SDValue GetGlobalReg(SelectionDAG &DAG, EVT Ty) {
54  MipsFunctionInfo *FI = DAG.getMachineFunction().getInfo<MipsFunctionInfo>();
55  return DAG.getRegister(FI->getGlobalBaseReg(), Ty);
56}
57
58const char *MipsTargetLowering::getTargetNodeName(unsigned Opcode) const {
59  switch (Opcode) {
60  case MipsISD::JmpLink:           return "MipsISD::JmpLink";
61  case MipsISD::Hi:                return "MipsISD::Hi";
62  case MipsISD::Lo:                return "MipsISD::Lo";
63  case MipsISD::GPRel:             return "MipsISD::GPRel";
64  case MipsISD::ThreadPointer:     return "MipsISD::ThreadPointer";
65  case MipsISD::Ret:               return "MipsISD::Ret";
66  case MipsISD::FPBrcond:          return "MipsISD::FPBrcond";
67  case MipsISD::FPCmp:             return "MipsISD::FPCmp";
68  case MipsISD::CMovFP_T:          return "MipsISD::CMovFP_T";
69  case MipsISD::CMovFP_F:          return "MipsISD::CMovFP_F";
70  case MipsISD::FPRound:           return "MipsISD::FPRound";
71  case MipsISD::MAdd:              return "MipsISD::MAdd";
72  case MipsISD::MAddu:             return "MipsISD::MAddu";
73  case MipsISD::MSub:              return "MipsISD::MSub";
74  case MipsISD::MSubu:             return "MipsISD::MSubu";
75  case MipsISD::DivRem:            return "MipsISD::DivRem";
76  case MipsISD::DivRemU:           return "MipsISD::DivRemU";
77  case MipsISD::BuildPairF64:      return "MipsISD::BuildPairF64";
78  case MipsISD::ExtractElementF64: return "MipsISD::ExtractElementF64";
79  case MipsISD::Wrapper:           return "MipsISD::Wrapper";
80  case MipsISD::DynAlloc:          return "MipsISD::DynAlloc";
81  case MipsISD::Sync:              return "MipsISD::Sync";
82  case MipsISD::Ext:               return "MipsISD::Ext";
83  case MipsISD::Ins:               return "MipsISD::Ins";
84  case MipsISD::LWL:               return "MipsISD::LWL";
85  case MipsISD::LWR:               return "MipsISD::LWR";
86  case MipsISD::SWL:               return "MipsISD::SWL";
87  case MipsISD::SWR:               return "MipsISD::SWR";
88  case MipsISD::LDL:               return "MipsISD::LDL";
89  case MipsISD::LDR:               return "MipsISD::LDR";
90  case MipsISD::SDL:               return "MipsISD::SDL";
91  case MipsISD::SDR:               return "MipsISD::SDR";
92  default:                         return NULL;
93  }
94}
95
96MipsTargetLowering::
97MipsTargetLowering(MipsTargetMachine &TM)
98  : TargetLowering(TM, new MipsTargetObjectFile()),
99    Subtarget(&TM.getSubtarget<MipsSubtarget>()),
100    HasMips64(Subtarget->hasMips64()), IsN64(Subtarget->isABI_N64()),
101    IsO32(Subtarget->isABI_O32()) {
102
103  // Mips does not have i1 type, so use i32 for
104  // setcc operations results (slt, sgt, ...).
105  setBooleanContents(ZeroOrOneBooleanContent);
106  setBooleanVectorContents(ZeroOrOneBooleanContent); // FIXME: Is this correct?
107
108  // Set up the register classes
109  addRegisterClass(MVT::i32, &Mips::CPURegsRegClass);
110
111  if (HasMips64)
112    addRegisterClass(MVT::i64, &Mips::CPU64RegsRegClass);
113
114  if (Subtarget->inMips16Mode()) {
115    addRegisterClass(MVT::i32, &Mips::CPU16RegsRegClass);
116    addRegisterClass(MVT::i32, &Mips::CPURARegRegClass);
117  }
118
119  if (!TM.Options.UseSoftFloat) {
120    addRegisterClass(MVT::f32, &Mips::FGR32RegClass);
121
122    // When dealing with single precision only, use libcalls
123    if (!Subtarget->isSingleFloat()) {
124      if (HasMips64)
125        addRegisterClass(MVT::f64, &Mips::FGR64RegClass);
126      else
127        addRegisterClass(MVT::f64, &Mips::AFGR64RegClass);
128    }
129  }
130
131  // Load extented operations for i1 types must be promoted
132  setLoadExtAction(ISD::EXTLOAD,  MVT::i1,  Promote);
133  setLoadExtAction(ISD::ZEXTLOAD, MVT::i1,  Promote);
134  setLoadExtAction(ISD::SEXTLOAD, MVT::i1,  Promote);
135
136  // MIPS doesn't have extending float->double load/store
137  setLoadExtAction(ISD::EXTLOAD, MVT::f32, Expand);
138  setTruncStoreAction(MVT::f64, MVT::f32, Expand);
139
140  // Used by legalize types to correctly generate the setcc result.
141  // Without this, every float setcc comes with a AND/OR with the result,
142  // we don't want this, since the fpcmp result goes to a flag register,
143  // which is used implicitly by brcond and select operations.
144  AddPromotedToType(ISD::SETCC, MVT::i1, MVT::i32);
145
146  // Mips Custom Operations
147  setOperationAction(ISD::GlobalAddress,      MVT::i32,   Custom);
148  setOperationAction(ISD::BlockAddress,       MVT::i32,   Custom);
149  setOperationAction(ISD::GlobalTLSAddress,   MVT::i32,   Custom);
150  setOperationAction(ISD::JumpTable,          MVT::i32,   Custom);
151  setOperationAction(ISD::ConstantPool,       MVT::i32,   Custom);
152  setOperationAction(ISD::SELECT,             MVT::f32,   Custom);
153  setOperationAction(ISD::SELECT,             MVT::f64,   Custom);
154  setOperationAction(ISD::SELECT,             MVT::i32,   Custom);
155  setOperationAction(ISD::SETCC,              MVT::f32,   Custom);
156  setOperationAction(ISD::SETCC,              MVT::f64,   Custom);
157  setOperationAction(ISD::BRCOND,             MVT::Other, Custom);
158  setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32,   Custom);
159  setOperationAction(ISD::VASTART,            MVT::Other, Custom);
160  setOperationAction(ISD::FCOPYSIGN,          MVT::f32,   Custom);
161  setOperationAction(ISD::FCOPYSIGN,          MVT::f64,   Custom);
162  setOperationAction(ISD::MEMBARRIER,         MVT::Other, Custom);
163  setOperationAction(ISD::ATOMIC_FENCE,       MVT::Other, Custom);
164  setOperationAction(ISD::LOAD,               MVT::i32, Custom);
165  setOperationAction(ISD::STORE,              MVT::i32, Custom);
166
167  if (!TM.Options.NoNaNsFPMath) {
168    setOperationAction(ISD::FABS,             MVT::f32,   Custom);
169    setOperationAction(ISD::FABS,             MVT::f64,   Custom);
170  }
171
172  if (HasMips64) {
173    setOperationAction(ISD::GlobalAddress,      MVT::i64,   Custom);
174    setOperationAction(ISD::BlockAddress,       MVT::i64,   Custom);
175    setOperationAction(ISD::GlobalTLSAddress,   MVT::i64,   Custom);
176    setOperationAction(ISD::JumpTable,          MVT::i64,   Custom);
177    setOperationAction(ISD::ConstantPool,       MVT::i64,   Custom);
178    setOperationAction(ISD::SELECT,             MVT::i64,   Custom);
179    setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i64,   Custom);
180    setOperationAction(ISD::LOAD,               MVT::i64,   Custom);
181    setOperationAction(ISD::STORE,              MVT::i64,   Custom);
182  }
183
184  if (!HasMips64) {
185    setOperationAction(ISD::SHL_PARTS,          MVT::i32,   Custom);
186    setOperationAction(ISD::SRA_PARTS,          MVT::i32,   Custom);
187    setOperationAction(ISD::SRL_PARTS,          MVT::i32,   Custom);
188  }
189
190  setOperationAction(ISD::SDIV, MVT::i32, Expand);
191  setOperationAction(ISD::SREM, MVT::i32, Expand);
192  setOperationAction(ISD::UDIV, MVT::i32, Expand);
193  setOperationAction(ISD::UREM, MVT::i32, Expand);
194  setOperationAction(ISD::SDIV, MVT::i64, Expand);
195  setOperationAction(ISD::SREM, MVT::i64, Expand);
196  setOperationAction(ISD::UDIV, MVT::i64, Expand);
197  setOperationAction(ISD::UREM, MVT::i64, Expand);
198
199  // Operations not directly supported by Mips.
200  setOperationAction(ISD::BR_JT,             MVT::Other, Expand);
201  setOperationAction(ISD::BR_CC,             MVT::Other, Expand);
202  setOperationAction(ISD::SELECT_CC,         MVT::Other, Expand);
203  setOperationAction(ISD::UINT_TO_FP,        MVT::i32,   Expand);
204  setOperationAction(ISD::UINT_TO_FP,        MVT::i64,   Expand);
205  setOperationAction(ISD::FP_TO_UINT,        MVT::i32,   Expand);
206  setOperationAction(ISD::FP_TO_UINT,        MVT::i64,   Expand);
207  setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i1,    Expand);
208  setOperationAction(ISD::CTPOP,             MVT::i32,   Expand);
209  setOperationAction(ISD::CTPOP,             MVT::i64,   Expand);
210  setOperationAction(ISD::CTTZ,              MVT::i32,   Expand);
211  setOperationAction(ISD::CTTZ,              MVT::i64,   Expand);
212  setOperationAction(ISD::CTTZ_ZERO_UNDEF,   MVT::i32,   Expand);
213  setOperationAction(ISD::CTTZ_ZERO_UNDEF,   MVT::i64,   Expand);
214  setOperationAction(ISD::CTLZ_ZERO_UNDEF,   MVT::i32,   Expand);
215  setOperationAction(ISD::CTLZ_ZERO_UNDEF,   MVT::i64,   Expand);
216  setOperationAction(ISD::ROTL,              MVT::i32,   Expand);
217  setOperationAction(ISD::ROTL,              MVT::i64,   Expand);
218
219  if (!Subtarget->hasMips32r2())
220    setOperationAction(ISD::ROTR, MVT::i32,   Expand);
221
222  if (!Subtarget->hasMips64r2())
223    setOperationAction(ISD::ROTR, MVT::i64,   Expand);
224
225  setOperationAction(ISD::FSIN,              MVT::f32,   Expand);
226  setOperationAction(ISD::FSIN,              MVT::f64,   Expand);
227  setOperationAction(ISD::FCOS,              MVT::f32,   Expand);
228  setOperationAction(ISD::FCOS,              MVT::f64,   Expand);
229  setOperationAction(ISD::FPOWI,             MVT::f32,   Expand);
230  setOperationAction(ISD::FPOW,              MVT::f32,   Expand);
231  setOperationAction(ISD::FPOW,              MVT::f64,   Expand);
232  setOperationAction(ISD::FLOG,              MVT::f32,   Expand);
233  setOperationAction(ISD::FLOG2,             MVT::f32,   Expand);
234  setOperationAction(ISD::FLOG10,            MVT::f32,   Expand);
235  setOperationAction(ISD::FEXP,              MVT::f32,   Expand);
236  setOperationAction(ISD::FMA,               MVT::f32,   Expand);
237  setOperationAction(ISD::FMA,               MVT::f64,   Expand);
238  setOperationAction(ISD::FREM,              MVT::f32,   Expand);
239  setOperationAction(ISD::FREM,              MVT::f64,   Expand);
240
241  if (!TM.Options.NoNaNsFPMath) {
242    setOperationAction(ISD::FNEG,             MVT::f32,   Expand);
243    setOperationAction(ISD::FNEG,             MVT::f64,   Expand);
244  }
245
246  setOperationAction(ISD::EXCEPTIONADDR,     MVT::i32, Expand);
247  setOperationAction(ISD::EXCEPTIONADDR,     MVT::i64, Expand);
248  setOperationAction(ISD::EHSELECTION,       MVT::i32, Expand);
249  setOperationAction(ISD::EHSELECTION,       MVT::i64, Expand);
250
251  setOperationAction(ISD::VAARG,             MVT::Other, Expand);
252  setOperationAction(ISD::VACOPY,            MVT::Other, Expand);
253  setOperationAction(ISD::VAEND,             MVT::Other, Expand);
254
255  // Use the default for now
256  setOperationAction(ISD::STACKSAVE,         MVT::Other, Expand);
257  setOperationAction(ISD::STACKRESTORE,      MVT::Other, Expand);
258
259  setOperationAction(ISD::ATOMIC_LOAD,       MVT::i32,    Expand);
260  setOperationAction(ISD::ATOMIC_LOAD,       MVT::i64,    Expand);
261  setOperationAction(ISD::ATOMIC_STORE,      MVT::i32,    Expand);
262  setOperationAction(ISD::ATOMIC_STORE,      MVT::i64,    Expand);
263
264  setInsertFencesForAtomic(true);
265
266  if (Subtarget->isSingleFloat())
267    setOperationAction(ISD::SELECT_CC, MVT::f64, Expand);
268
269  if (!Subtarget->hasSEInReg()) {
270    setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i8,  Expand);
271    setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i16, Expand);
272  }
273
274  if (!Subtarget->hasBitCount()) {
275    setOperationAction(ISD::CTLZ, MVT::i32, Expand);
276    setOperationAction(ISD::CTLZ, MVT::i64, Expand);
277  }
278
279  if (!Subtarget->hasSwap()) {
280    setOperationAction(ISD::BSWAP, MVT::i32, Expand);
281    setOperationAction(ISD::BSWAP, MVT::i64, Expand);
282  }
283
284  if (HasMips64) {
285    setLoadExtAction(ISD::SEXTLOAD, MVT::i32, Custom);
286    setLoadExtAction(ISD::ZEXTLOAD, MVT::i32, Custom);
287    setLoadExtAction(ISD::EXTLOAD, MVT::i32, Custom);
288    setTruncStoreAction(MVT::i64, MVT::i32, Custom);
289  }
290
291  setTargetDAGCombine(ISD::ADDE);
292  setTargetDAGCombine(ISD::SUBE);
293  setTargetDAGCombine(ISD::SDIVREM);
294  setTargetDAGCombine(ISD::UDIVREM);
295  setTargetDAGCombine(ISD::SELECT);
296  setTargetDAGCombine(ISD::AND);
297  setTargetDAGCombine(ISD::OR);
298
299  setMinFunctionAlignment(HasMips64 ? 3 : 2);
300
301  setStackPointerRegisterToSaveRestore(IsN64 ? Mips::SP_64 : Mips::SP);
302  computeRegisterProperties();
303
304  setExceptionPointerRegister(IsN64 ? Mips::A0_64 : Mips::A0);
305  setExceptionSelectorRegister(IsN64 ? Mips::A1_64 : Mips::A1);
306}
307
308bool MipsTargetLowering::allowsUnalignedMemoryAccesses(EVT VT) const {
309  MVT::SimpleValueType SVT = VT.getSimpleVT().SimpleTy;
310
311  switch (SVT) {
312  case MVT::i64:
313  case MVT::i32:
314    return true;
315  case MVT::f32:
316    return Subtarget->hasMips32r2Or64();
317  default:
318    return false;
319  }
320}
321
322EVT MipsTargetLowering::getSetCCResultType(EVT VT) const {
323  return MVT::i32;
324}
325
326// SelectMadd -
327// Transforms a subgraph in CurDAG if the following pattern is found:
328//  (addc multLo, Lo0), (adde multHi, Hi0),
329// where,
330//  multHi/Lo: product of multiplication
331//  Lo0: initial value of Lo register
332//  Hi0: initial value of Hi register
333// Return true if pattern matching was successful.
334static bool SelectMadd(SDNode* ADDENode, SelectionDAG* CurDAG) {
335  // ADDENode's second operand must be a flag output of an ADDC node in order
336  // for the matching to be successful.
337  SDNode* ADDCNode = ADDENode->getOperand(2).getNode();
338
339  if (ADDCNode->getOpcode() != ISD::ADDC)
340    return false;
341
342  SDValue MultHi = ADDENode->getOperand(0);
343  SDValue MultLo = ADDCNode->getOperand(0);
344  SDNode* MultNode = MultHi.getNode();
345  unsigned MultOpc = MultHi.getOpcode();
346
347  // MultHi and MultLo must be generated by the same node,
348  if (MultLo.getNode() != MultNode)
349    return false;
350
351  // and it must be a multiplication.
352  if (MultOpc != ISD::SMUL_LOHI && MultOpc != ISD::UMUL_LOHI)
353    return false;
354
355  // MultLo amd MultHi must be the first and second output of MultNode
356  // respectively.
357  if (MultHi.getResNo() != 1 || MultLo.getResNo() != 0)
358    return false;
359
360  // Transform this to a MADD only if ADDENode and ADDCNode are the only users
361  // of the values of MultNode, in which case MultNode will be removed in later
362  // phases.
363  // If there exist users other than ADDENode or ADDCNode, this function returns
364  // here, which will result in MultNode being mapped to a single MULT
365  // instruction node rather than a pair of MULT and MADD instructions being
366  // produced.
367  if (!MultHi.hasOneUse() || !MultLo.hasOneUse())
368    return false;
369
370  SDValue Chain = CurDAG->getEntryNode();
371  DebugLoc dl = ADDENode->getDebugLoc();
372
373  // create MipsMAdd(u) node
374  MultOpc = MultOpc == ISD::UMUL_LOHI ? MipsISD::MAddu : MipsISD::MAdd;
375
376  SDValue MAdd = CurDAG->getNode(MultOpc, dl, MVT::Glue,
377                                 MultNode->getOperand(0),// Factor 0
378                                 MultNode->getOperand(1),// Factor 1
379                                 ADDCNode->getOperand(1),// Lo0
380                                 ADDENode->getOperand(1));// Hi0
381
382  // create CopyFromReg nodes
383  SDValue CopyFromLo = CurDAG->getCopyFromReg(Chain, dl, Mips::LO, MVT::i32,
384                                              MAdd);
385  SDValue CopyFromHi = CurDAG->getCopyFromReg(CopyFromLo.getValue(1), dl,
386                                              Mips::HI, MVT::i32,
387                                              CopyFromLo.getValue(2));
388
389  // replace uses of adde and addc here
390  if (!SDValue(ADDCNode, 0).use_empty())
391    CurDAG->ReplaceAllUsesOfValueWith(SDValue(ADDCNode, 0), CopyFromLo);
392
393  if (!SDValue(ADDENode, 0).use_empty())
394    CurDAG->ReplaceAllUsesOfValueWith(SDValue(ADDENode, 0), CopyFromHi);
395
396  return true;
397}
398
399// SelectMsub -
400// Transforms a subgraph in CurDAG if the following pattern is found:
401//  (addc Lo0, multLo), (sube Hi0, multHi),
402// where,
403//  multHi/Lo: product of multiplication
404//  Lo0: initial value of Lo register
405//  Hi0: initial value of Hi register
406// Return true if pattern matching was successful.
407static bool SelectMsub(SDNode* SUBENode, SelectionDAG* CurDAG) {
408  // SUBENode's second operand must be a flag output of an SUBC node in order
409  // for the matching to be successful.
410  SDNode* SUBCNode = SUBENode->getOperand(2).getNode();
411
412  if (SUBCNode->getOpcode() != ISD::SUBC)
413    return false;
414
415  SDValue MultHi = SUBENode->getOperand(1);
416  SDValue MultLo = SUBCNode->getOperand(1);
417  SDNode* MultNode = MultHi.getNode();
418  unsigned MultOpc = MultHi.getOpcode();
419
420  // MultHi and MultLo must be generated by the same node,
421  if (MultLo.getNode() != MultNode)
422    return false;
423
424  // and it must be a multiplication.
425  if (MultOpc != ISD::SMUL_LOHI && MultOpc != ISD::UMUL_LOHI)
426    return false;
427
428  // MultLo amd MultHi must be the first and second output of MultNode
429  // respectively.
430  if (MultHi.getResNo() != 1 || MultLo.getResNo() != 0)
431    return false;
432
433  // Transform this to a MSUB only if SUBENode and SUBCNode are the only users
434  // of the values of MultNode, in which case MultNode will be removed in later
435  // phases.
436  // If there exist users other than SUBENode or SUBCNode, this function returns
437  // here, which will result in MultNode being mapped to a single MULT
438  // instruction node rather than a pair of MULT and MSUB instructions being
439  // produced.
440  if (!MultHi.hasOneUse() || !MultLo.hasOneUse())
441    return false;
442
443  SDValue Chain = CurDAG->getEntryNode();
444  DebugLoc dl = SUBENode->getDebugLoc();
445
446  // create MipsSub(u) node
447  MultOpc = MultOpc == ISD::UMUL_LOHI ? MipsISD::MSubu : MipsISD::MSub;
448
449  SDValue MSub = CurDAG->getNode(MultOpc, dl, MVT::Glue,
450                                 MultNode->getOperand(0),// Factor 0
451                                 MultNode->getOperand(1),// Factor 1
452                                 SUBCNode->getOperand(0),// Lo0
453                                 SUBENode->getOperand(0));// Hi0
454
455  // create CopyFromReg nodes
456  SDValue CopyFromLo = CurDAG->getCopyFromReg(Chain, dl, Mips::LO, MVT::i32,
457                                              MSub);
458  SDValue CopyFromHi = CurDAG->getCopyFromReg(CopyFromLo.getValue(1), dl,
459                                              Mips::HI, MVT::i32,
460                                              CopyFromLo.getValue(2));
461
462  // replace uses of sube and subc here
463  if (!SDValue(SUBCNode, 0).use_empty())
464    CurDAG->ReplaceAllUsesOfValueWith(SDValue(SUBCNode, 0), CopyFromLo);
465
466  if (!SDValue(SUBENode, 0).use_empty())
467    CurDAG->ReplaceAllUsesOfValueWith(SDValue(SUBENode, 0), CopyFromHi);
468
469  return true;
470}
471
472static SDValue PerformADDECombine(SDNode *N, SelectionDAG& DAG,
473                                  TargetLowering::DAGCombinerInfo &DCI,
474                                  const MipsSubtarget* Subtarget) {
475  if (DCI.isBeforeLegalize())
476    return SDValue();
477
478  if (Subtarget->hasMips32() && N->getValueType(0) == MVT::i32 &&
479      SelectMadd(N, &DAG))
480    return SDValue(N, 0);
481
482  return SDValue();
483}
484
485static SDValue PerformSUBECombine(SDNode *N, SelectionDAG& DAG,
486                                  TargetLowering::DAGCombinerInfo &DCI,
487                                  const MipsSubtarget* Subtarget) {
488  if (DCI.isBeforeLegalize())
489    return SDValue();
490
491  if (Subtarget->hasMips32() && N->getValueType(0) == MVT::i32 &&
492      SelectMsub(N, &DAG))
493    return SDValue(N, 0);
494
495  return SDValue();
496}
497
498static SDValue PerformDivRemCombine(SDNode *N, SelectionDAG& DAG,
499                                    TargetLowering::DAGCombinerInfo &DCI,
500                                    const MipsSubtarget* Subtarget) {
501  if (DCI.isBeforeLegalizeOps())
502    return SDValue();
503
504  EVT Ty = N->getValueType(0);
505  unsigned LO = (Ty == MVT::i32) ? Mips::LO : Mips::LO64;
506  unsigned HI = (Ty == MVT::i32) ? Mips::HI : Mips::HI64;
507  unsigned opc = N->getOpcode() == ISD::SDIVREM ? MipsISD::DivRem :
508                                                  MipsISD::DivRemU;
509  DebugLoc dl = N->getDebugLoc();
510
511  SDValue DivRem = DAG.getNode(opc, dl, MVT::Glue,
512                               N->getOperand(0), N->getOperand(1));
513  SDValue InChain = DAG.getEntryNode();
514  SDValue InGlue = DivRem;
515
516  // insert MFLO
517  if (N->hasAnyUseOfValue(0)) {
518    SDValue CopyFromLo = DAG.getCopyFromReg(InChain, dl, LO, Ty,
519                                            InGlue);
520    DAG.ReplaceAllUsesOfValueWith(SDValue(N, 0), CopyFromLo);
521    InChain = CopyFromLo.getValue(1);
522    InGlue = CopyFromLo.getValue(2);
523  }
524
525  // insert MFHI
526  if (N->hasAnyUseOfValue(1)) {
527    SDValue CopyFromHi = DAG.getCopyFromReg(InChain, dl,
528                                            HI, Ty, InGlue);
529    DAG.ReplaceAllUsesOfValueWith(SDValue(N, 1), CopyFromHi);
530  }
531
532  return SDValue();
533}
534
535static Mips::CondCode FPCondCCodeToFCC(ISD::CondCode CC) {
536  switch (CC) {
537  default: llvm_unreachable("Unknown fp condition code!");
538  case ISD::SETEQ:
539  case ISD::SETOEQ: return Mips::FCOND_OEQ;
540  case ISD::SETUNE: return Mips::FCOND_UNE;
541  case ISD::SETLT:
542  case ISD::SETOLT: return Mips::FCOND_OLT;
543  case ISD::SETGT:
544  case ISD::SETOGT: return Mips::FCOND_OGT;
545  case ISD::SETLE:
546  case ISD::SETOLE: return Mips::FCOND_OLE;
547  case ISD::SETGE:
548  case ISD::SETOGE: return Mips::FCOND_OGE;
549  case ISD::SETULT: return Mips::FCOND_ULT;
550  case ISD::SETULE: return Mips::FCOND_ULE;
551  case ISD::SETUGT: return Mips::FCOND_UGT;
552  case ISD::SETUGE: return Mips::FCOND_UGE;
553  case ISD::SETUO:  return Mips::FCOND_UN;
554  case ISD::SETO:   return Mips::FCOND_OR;
555  case ISD::SETNE:
556  case ISD::SETONE: return Mips::FCOND_ONE;
557  case ISD::SETUEQ: return Mips::FCOND_UEQ;
558  }
559}
560
561
562// Returns true if condition code has to be inverted.
563static bool InvertFPCondCode(Mips::CondCode CC) {
564  if (CC >= Mips::FCOND_F && CC <= Mips::FCOND_NGT)
565    return false;
566
567  assert((CC >= Mips::FCOND_T && CC <= Mips::FCOND_GT) &&
568         "Illegal Condition Code");
569
570  return true;
571}
572
573// Creates and returns an FPCmp node from a setcc node.
574// Returns Op if setcc is not a floating point comparison.
575static SDValue CreateFPCmp(SelectionDAG& DAG, const SDValue& Op) {
576  // must be a SETCC node
577  if (Op.getOpcode() != ISD::SETCC)
578    return Op;
579
580  SDValue LHS = Op.getOperand(0);
581
582  if (!LHS.getValueType().isFloatingPoint())
583    return Op;
584
585  SDValue RHS = Op.getOperand(1);
586  DebugLoc dl = Op.getDebugLoc();
587
588  // Assume the 3rd operand is a CondCodeSDNode. Add code to check the type of
589  // node if necessary.
590  ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(2))->get();
591
592  return DAG.getNode(MipsISD::FPCmp, dl, MVT::Glue, LHS, RHS,
593                     DAG.getConstant(FPCondCCodeToFCC(CC), MVT::i32));
594}
595
596// Creates and returns a CMovFPT/F node.
597static SDValue CreateCMovFP(SelectionDAG& DAG, SDValue Cond, SDValue True,
598                            SDValue False, DebugLoc DL) {
599  bool invert = InvertFPCondCode((Mips::CondCode)
600                                 cast<ConstantSDNode>(Cond.getOperand(2))
601                                 ->getSExtValue());
602
603  return DAG.getNode((invert ? MipsISD::CMovFP_F : MipsISD::CMovFP_T), DL,
604                     True.getValueType(), True, False, Cond);
605}
606
607static SDValue PerformSELECTCombine(SDNode *N, SelectionDAG& DAG,
608                                    TargetLowering::DAGCombinerInfo &DCI,
609                                    const MipsSubtarget* Subtarget) {
610  if (DCI.isBeforeLegalizeOps())
611    return SDValue();
612
613  SDValue SetCC = N->getOperand(0);
614
615  if ((SetCC.getOpcode() != ISD::SETCC) ||
616      !SetCC.getOperand(0).getValueType().isInteger())
617    return SDValue();
618
619  SDValue False = N->getOperand(2);
620  EVT FalseTy = False.getValueType();
621
622  if (!FalseTy.isInteger())
623    return SDValue();
624
625  ConstantSDNode *CN = dyn_cast<ConstantSDNode>(False);
626
627  if (!CN || CN->getZExtValue())
628    return SDValue();
629
630  const DebugLoc DL = N->getDebugLoc();
631  ISD::CondCode CC = cast<CondCodeSDNode>(SetCC.getOperand(2))->get();
632  SDValue True = N->getOperand(1);
633
634  SetCC = DAG.getSetCC(DL, SetCC.getValueType(), SetCC.getOperand(0),
635                       SetCC.getOperand(1), ISD::getSetCCInverse(CC, true));
636
637  return DAG.getNode(ISD::SELECT, DL, FalseTy, SetCC, False, True);
638}
639
640static SDValue PerformANDCombine(SDNode *N, SelectionDAG& DAG,
641                                 TargetLowering::DAGCombinerInfo &DCI,
642                                 const MipsSubtarget* Subtarget) {
643  // Pattern match EXT.
644  //  $dst = and ((sra or srl) $src , pos), (2**size - 1)
645  //  => ext $dst, $src, size, pos
646  if (DCI.isBeforeLegalizeOps() || !Subtarget->hasMips32r2())
647    return SDValue();
648
649  SDValue ShiftRight = N->getOperand(0), Mask = N->getOperand(1);
650  unsigned ShiftRightOpc = ShiftRight.getOpcode();
651
652  // Op's first operand must be a shift right.
653  if (ShiftRightOpc != ISD::SRA && ShiftRightOpc != ISD::SRL)
654    return SDValue();
655
656  // The second operand of the shift must be an immediate.
657  ConstantSDNode *CN;
658  if (!(CN = dyn_cast<ConstantSDNode>(ShiftRight.getOperand(1))))
659    return SDValue();
660
661  uint64_t Pos = CN->getZExtValue();
662  uint64_t SMPos, SMSize;
663
664  // Op's second operand must be a shifted mask.
665  if (!(CN = dyn_cast<ConstantSDNode>(Mask)) ||
666      !IsShiftedMask(CN->getZExtValue(), SMPos, SMSize))
667    return SDValue();
668
669  // Return if the shifted mask does not start at bit 0 or the sum of its size
670  // and Pos exceeds the word's size.
671  EVT ValTy = N->getValueType(0);
672  if (SMPos != 0 || Pos + SMSize > ValTy.getSizeInBits())
673    return SDValue();
674
675  return DAG.getNode(MipsISD::Ext, N->getDebugLoc(), ValTy,
676                     ShiftRight.getOperand(0), DAG.getConstant(Pos, MVT::i32),
677                     DAG.getConstant(SMSize, MVT::i32));
678}
679
680static SDValue PerformORCombine(SDNode *N, SelectionDAG& DAG,
681                                TargetLowering::DAGCombinerInfo &DCI,
682                                const MipsSubtarget* Subtarget) {
683  // Pattern match INS.
684  //  $dst = or (and $src1 , mask0), (and (shl $src, pos), mask1),
685  //  where mask1 = (2**size - 1) << pos, mask0 = ~mask1
686  //  => ins $dst, $src, size, pos, $src1
687  if (DCI.isBeforeLegalizeOps() || !Subtarget->hasMips32r2())
688    return SDValue();
689
690  SDValue And0 = N->getOperand(0), And1 = N->getOperand(1);
691  uint64_t SMPos0, SMSize0, SMPos1, SMSize1;
692  ConstantSDNode *CN;
693
694  // See if Op's first operand matches (and $src1 , mask0).
695  if (And0.getOpcode() != ISD::AND)
696    return SDValue();
697
698  if (!(CN = dyn_cast<ConstantSDNode>(And0.getOperand(1))) ||
699      !IsShiftedMask(~CN->getSExtValue(), SMPos0, SMSize0))
700    return SDValue();
701
702  // See if Op's second operand matches (and (shl $src, pos), mask1).
703  if (And1.getOpcode() != ISD::AND)
704    return SDValue();
705
706  if (!(CN = dyn_cast<ConstantSDNode>(And1.getOperand(1))) ||
707      !IsShiftedMask(CN->getZExtValue(), SMPos1, SMSize1))
708    return SDValue();
709
710  // The shift masks must have the same position and size.
711  if (SMPos0 != SMPos1 || SMSize0 != SMSize1)
712    return SDValue();
713
714  SDValue Shl = And1.getOperand(0);
715  if (Shl.getOpcode() != ISD::SHL)
716    return SDValue();
717
718  if (!(CN = dyn_cast<ConstantSDNode>(Shl.getOperand(1))))
719    return SDValue();
720
721  unsigned Shamt = CN->getZExtValue();
722
723  // Return if the shift amount and the first bit position of mask are not the
724  // same.
725  EVT ValTy = N->getValueType(0);
726  if ((Shamt != SMPos0) || (SMPos0 + SMSize0 > ValTy.getSizeInBits()))
727    return SDValue();
728
729  return DAG.getNode(MipsISD::Ins, N->getDebugLoc(), ValTy, Shl.getOperand(0),
730                     DAG.getConstant(SMPos0, MVT::i32),
731                     DAG.getConstant(SMSize0, MVT::i32), And0.getOperand(0));
732}
733
734SDValue  MipsTargetLowering::PerformDAGCombine(SDNode *N, DAGCombinerInfo &DCI)
735  const {
736  SelectionDAG &DAG = DCI.DAG;
737  unsigned opc = N->getOpcode();
738
739  switch (opc) {
740  default: break;
741  case ISD::ADDE:
742    return PerformADDECombine(N, DAG, DCI, Subtarget);
743  case ISD::SUBE:
744    return PerformSUBECombine(N, DAG, DCI, Subtarget);
745  case ISD::SDIVREM:
746  case ISD::UDIVREM:
747    return PerformDivRemCombine(N, DAG, DCI, Subtarget);
748  case ISD::SELECT:
749    return PerformSELECTCombine(N, DAG, DCI, Subtarget);
750  case ISD::AND:
751    return PerformANDCombine(N, DAG, DCI, Subtarget);
752  case ISD::OR:
753    return PerformORCombine(N, DAG, DCI, Subtarget);
754  }
755
756  return SDValue();
757}
758
759SDValue MipsTargetLowering::
760LowerOperation(SDValue Op, SelectionDAG &DAG) const
761{
762  switch (Op.getOpcode())
763  {
764    case ISD::BRCOND:             return LowerBRCOND(Op, DAG);
765    case ISD::ConstantPool:       return LowerConstantPool(Op, DAG);
766    case ISD::DYNAMIC_STACKALLOC: return LowerDYNAMIC_STACKALLOC(Op, DAG);
767    case ISD::GlobalAddress:      return LowerGlobalAddress(Op, DAG);
768    case ISD::BlockAddress:       return LowerBlockAddress(Op, DAG);
769    case ISD::GlobalTLSAddress:   return LowerGlobalTLSAddress(Op, DAG);
770    case ISD::JumpTable:          return LowerJumpTable(Op, DAG);
771    case ISD::SELECT:             return LowerSELECT(Op, DAG);
772    case ISD::SETCC:              return LowerSETCC(Op, DAG);
773    case ISD::VASTART:            return LowerVASTART(Op, DAG);
774    case ISD::FCOPYSIGN:          return LowerFCOPYSIGN(Op, DAG);
775    case ISD::FABS:               return LowerFABS(Op, DAG);
776    case ISD::FRAMEADDR:          return LowerFRAMEADDR(Op, DAG);
777    case ISD::MEMBARRIER:         return LowerMEMBARRIER(Op, DAG);
778    case ISD::ATOMIC_FENCE:       return LowerATOMIC_FENCE(Op, DAG);
779    case ISD::SHL_PARTS:          return LowerShiftLeftParts(Op, DAG);
780    case ISD::SRA_PARTS:          return LowerShiftRightParts(Op, DAG, true);
781    case ISD::SRL_PARTS:          return LowerShiftRightParts(Op, DAG, false);
782    case ISD::LOAD:               return LowerLOAD(Op, DAG);
783    case ISD::STORE:              return LowerSTORE(Op, DAG);
784  }
785  return SDValue();
786}
787
788//===----------------------------------------------------------------------===//
789//  Lower helper functions
790//===----------------------------------------------------------------------===//
791
792// AddLiveIn - This helper function adds the specified physical register to the
793// MachineFunction as a live in value.  It also creates a corresponding
794// virtual register for it.
795static unsigned
796AddLiveIn(MachineFunction &MF, unsigned PReg, const TargetRegisterClass *RC)
797{
798  assert(RC->contains(PReg) && "Not the correct regclass!");
799  unsigned VReg = MF.getRegInfo().createVirtualRegister(RC);
800  MF.getRegInfo().addLiveIn(PReg, VReg);
801  return VReg;
802}
803
804// Get fp branch code (not opcode) from condition code.
805static Mips::FPBranchCode GetFPBranchCodeFromCond(Mips::CondCode CC) {
806  if (CC >= Mips::FCOND_F && CC <= Mips::FCOND_NGT)
807    return Mips::BRANCH_T;
808
809  assert((CC >= Mips::FCOND_T && CC <= Mips::FCOND_GT) &&
810         "Invalid CondCode.");
811
812  return Mips::BRANCH_F;
813}
814
815/*
816static MachineBasicBlock* ExpandCondMov(MachineInstr *MI, MachineBasicBlock *BB,
817                                        DebugLoc dl,
818                                        const MipsSubtarget* Subtarget,
819                                        const TargetInstrInfo *TII,
820                                        bool isFPCmp, unsigned Opc) {
821  // There is no need to expand CMov instructions if target has
822  // conditional moves.
823  if (Subtarget->hasCondMov())
824    return BB;
825
826  // To "insert" a SELECT_CC instruction, we actually have to insert the
827  // diamond control-flow pattern.  The incoming instruction knows the
828  // destination vreg to set, the condition code register to branch on, the
829  // true/false values to select between, and a branch opcode to use.
830  const BasicBlock *LLVM_BB = BB->getBasicBlock();
831  MachineFunction::iterator It = BB;
832  ++It;
833
834  //  thisMBB:
835  //  ...
836  //   TrueVal = ...
837  //   setcc r1, r2, r3
838  //   bNE   r1, r0, copy1MBB
839  //   fallthrough --> copy0MBB
840  MachineBasicBlock *thisMBB  = BB;
841  MachineFunction *F = BB->getParent();
842  MachineBasicBlock *copy0MBB = F->CreateMachineBasicBlock(LLVM_BB);
843  MachineBasicBlock *sinkMBB  = F->CreateMachineBasicBlock(LLVM_BB);
844  F->insert(It, copy0MBB);
845  F->insert(It, sinkMBB);
846
847  // Transfer the remainder of BB and its successor edges to sinkMBB.
848  sinkMBB->splice(sinkMBB->begin(), BB,
849                  llvm::next(MachineBasicBlock::iterator(MI)),
850                  BB->end());
851  sinkMBB->transferSuccessorsAndUpdatePHIs(BB);
852
853  // Next, add the true and fallthrough blocks as its successors.
854  BB->addSuccessor(copy0MBB);
855  BB->addSuccessor(sinkMBB);
856
857  // Emit the right instruction according to the type of the operands compared
858  if (isFPCmp)
859    BuildMI(BB, dl, TII->get(Opc)).addMBB(sinkMBB);
860  else
861    BuildMI(BB, dl, TII->get(Opc)).addReg(MI->getOperand(2).getReg())
862      .addReg(Mips::ZERO).addMBB(sinkMBB);
863
864  //  copy0MBB:
865  //   %FalseValue = ...
866  //   # fallthrough to sinkMBB
867  BB = copy0MBB;
868
869  // Update machine-CFG edges
870  BB->addSuccessor(sinkMBB);
871
872  //  sinkMBB:
873  //   %Result = phi [ %TrueValue, thisMBB ], [ %FalseValue, copy0MBB ]
874  //  ...
875  BB = sinkMBB;
876
877  if (isFPCmp)
878    BuildMI(*BB, BB->begin(), dl,
879            TII->get(Mips::PHI), MI->getOperand(0).getReg())
880      .addReg(MI->getOperand(2).getReg()).addMBB(thisMBB)
881      .addReg(MI->getOperand(1).getReg()).addMBB(copy0MBB);
882  else
883    BuildMI(*BB, BB->begin(), dl,
884            TII->get(Mips::PHI), MI->getOperand(0).getReg())
885      .addReg(MI->getOperand(3).getReg()).addMBB(thisMBB)
886      .addReg(MI->getOperand(1).getReg()).addMBB(copy0MBB);
887
888  MI->eraseFromParent();   // The pseudo instruction is gone now.
889  return BB;
890}
891*/
892MachineBasicBlock *
893MipsTargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
894                                                MachineBasicBlock *BB) const {
895  switch (MI->getOpcode()) {
896  default: llvm_unreachable("Unexpected instr type to insert");
897  case Mips::ATOMIC_LOAD_ADD_I8:
898  case Mips::ATOMIC_LOAD_ADD_I8_P8:
899    return EmitAtomicBinaryPartword(MI, BB, 1, Mips::ADDu);
900  case Mips::ATOMIC_LOAD_ADD_I16:
901  case Mips::ATOMIC_LOAD_ADD_I16_P8:
902    return EmitAtomicBinaryPartword(MI, BB, 2, Mips::ADDu);
903  case Mips::ATOMIC_LOAD_ADD_I32:
904  case Mips::ATOMIC_LOAD_ADD_I32_P8:
905    return EmitAtomicBinary(MI, BB, 4, Mips::ADDu);
906  case Mips::ATOMIC_LOAD_ADD_I64:
907  case Mips::ATOMIC_LOAD_ADD_I64_P8:
908    return EmitAtomicBinary(MI, BB, 8, Mips::DADDu);
909
910  case Mips::ATOMIC_LOAD_AND_I8:
911  case Mips::ATOMIC_LOAD_AND_I8_P8:
912    return EmitAtomicBinaryPartword(MI, BB, 1, Mips::AND);
913  case Mips::ATOMIC_LOAD_AND_I16:
914  case Mips::ATOMIC_LOAD_AND_I16_P8:
915    return EmitAtomicBinaryPartword(MI, BB, 2, Mips::AND);
916  case Mips::ATOMIC_LOAD_AND_I32:
917  case Mips::ATOMIC_LOAD_AND_I32_P8:
918    return EmitAtomicBinary(MI, BB, 4, Mips::AND);
919  case Mips::ATOMIC_LOAD_AND_I64:
920  case Mips::ATOMIC_LOAD_AND_I64_P8:
921    return EmitAtomicBinary(MI, BB, 8, Mips::AND64);
922
923  case Mips::ATOMIC_LOAD_OR_I8:
924  case Mips::ATOMIC_LOAD_OR_I8_P8:
925    return EmitAtomicBinaryPartword(MI, BB, 1, Mips::OR);
926  case Mips::ATOMIC_LOAD_OR_I16:
927  case Mips::ATOMIC_LOAD_OR_I16_P8:
928    return EmitAtomicBinaryPartword(MI, BB, 2, Mips::OR);
929  case Mips::ATOMIC_LOAD_OR_I32:
930  case Mips::ATOMIC_LOAD_OR_I32_P8:
931    return EmitAtomicBinary(MI, BB, 4, Mips::OR);
932  case Mips::ATOMIC_LOAD_OR_I64:
933  case Mips::ATOMIC_LOAD_OR_I64_P8:
934    return EmitAtomicBinary(MI, BB, 8, Mips::OR64);
935
936  case Mips::ATOMIC_LOAD_XOR_I8:
937  case Mips::ATOMIC_LOAD_XOR_I8_P8:
938    return EmitAtomicBinaryPartword(MI, BB, 1, Mips::XOR);
939  case Mips::ATOMIC_LOAD_XOR_I16:
940  case Mips::ATOMIC_LOAD_XOR_I16_P8:
941    return EmitAtomicBinaryPartword(MI, BB, 2, Mips::XOR);
942  case Mips::ATOMIC_LOAD_XOR_I32:
943  case Mips::ATOMIC_LOAD_XOR_I32_P8:
944    return EmitAtomicBinary(MI, BB, 4, Mips::XOR);
945  case Mips::ATOMIC_LOAD_XOR_I64:
946  case Mips::ATOMIC_LOAD_XOR_I64_P8:
947    return EmitAtomicBinary(MI, BB, 8, Mips::XOR64);
948
949  case Mips::ATOMIC_LOAD_NAND_I8:
950  case Mips::ATOMIC_LOAD_NAND_I8_P8:
951    return EmitAtomicBinaryPartword(MI, BB, 1, 0, true);
952  case Mips::ATOMIC_LOAD_NAND_I16:
953  case Mips::ATOMIC_LOAD_NAND_I16_P8:
954    return EmitAtomicBinaryPartword(MI, BB, 2, 0, true);
955  case Mips::ATOMIC_LOAD_NAND_I32:
956  case Mips::ATOMIC_LOAD_NAND_I32_P8:
957    return EmitAtomicBinary(MI, BB, 4, 0, true);
958  case Mips::ATOMIC_LOAD_NAND_I64:
959  case Mips::ATOMIC_LOAD_NAND_I64_P8:
960    return EmitAtomicBinary(MI, BB, 8, 0, true);
961
962  case Mips::ATOMIC_LOAD_SUB_I8:
963  case Mips::ATOMIC_LOAD_SUB_I8_P8:
964    return EmitAtomicBinaryPartword(MI, BB, 1, Mips::SUBu);
965  case Mips::ATOMIC_LOAD_SUB_I16:
966  case Mips::ATOMIC_LOAD_SUB_I16_P8:
967    return EmitAtomicBinaryPartword(MI, BB, 2, Mips::SUBu);
968  case Mips::ATOMIC_LOAD_SUB_I32:
969  case Mips::ATOMIC_LOAD_SUB_I32_P8:
970    return EmitAtomicBinary(MI, BB, 4, Mips::SUBu);
971  case Mips::ATOMIC_LOAD_SUB_I64:
972  case Mips::ATOMIC_LOAD_SUB_I64_P8:
973    return EmitAtomicBinary(MI, BB, 8, Mips::DSUBu);
974
975  case Mips::ATOMIC_SWAP_I8:
976  case Mips::ATOMIC_SWAP_I8_P8:
977    return EmitAtomicBinaryPartword(MI, BB, 1, 0);
978  case Mips::ATOMIC_SWAP_I16:
979  case Mips::ATOMIC_SWAP_I16_P8:
980    return EmitAtomicBinaryPartword(MI, BB, 2, 0);
981  case Mips::ATOMIC_SWAP_I32:
982  case Mips::ATOMIC_SWAP_I32_P8:
983    return EmitAtomicBinary(MI, BB, 4, 0);
984  case Mips::ATOMIC_SWAP_I64:
985  case Mips::ATOMIC_SWAP_I64_P8:
986    return EmitAtomicBinary(MI, BB, 8, 0);
987
988  case Mips::ATOMIC_CMP_SWAP_I8:
989  case Mips::ATOMIC_CMP_SWAP_I8_P8:
990    return EmitAtomicCmpSwapPartword(MI, BB, 1);
991  case Mips::ATOMIC_CMP_SWAP_I16:
992  case Mips::ATOMIC_CMP_SWAP_I16_P8:
993    return EmitAtomicCmpSwapPartword(MI, BB, 2);
994  case Mips::ATOMIC_CMP_SWAP_I32:
995  case Mips::ATOMIC_CMP_SWAP_I32_P8:
996    return EmitAtomicCmpSwap(MI, BB, 4);
997  case Mips::ATOMIC_CMP_SWAP_I64:
998  case Mips::ATOMIC_CMP_SWAP_I64_P8:
999    return EmitAtomicCmpSwap(MI, BB, 8);
1000  }
1001}
1002
1003// This function also handles Mips::ATOMIC_SWAP_I32 (when BinOpcode == 0), and
1004// Mips::ATOMIC_LOAD_NAND_I32 (when Nand == true)
1005MachineBasicBlock *
1006MipsTargetLowering::EmitAtomicBinary(MachineInstr *MI, MachineBasicBlock *BB,
1007                                     unsigned Size, unsigned BinOpcode,
1008                                     bool Nand) const {
1009  assert((Size == 4 || Size == 8) && "Unsupported size for EmitAtomicBinary.");
1010
1011  MachineFunction *MF = BB->getParent();
1012  MachineRegisterInfo &RegInfo = MF->getRegInfo();
1013  const TargetRegisterClass *RC = getRegClassFor(MVT::getIntegerVT(Size * 8));
1014  const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
1015  DebugLoc dl = MI->getDebugLoc();
1016  unsigned LL, SC, AND, NOR, ZERO, BEQ;
1017
1018  if (Size == 4) {
1019    LL = IsN64 ? Mips::LL_P8 : Mips::LL;
1020    SC = IsN64 ? Mips::SC_P8 : Mips::SC;
1021    AND = Mips::AND;
1022    NOR = Mips::NOR;
1023    ZERO = Mips::ZERO;
1024    BEQ = Mips::BEQ;
1025  }
1026  else {
1027    LL = IsN64 ? Mips::LLD_P8 : Mips::LLD;
1028    SC = IsN64 ? Mips::SCD_P8 : Mips::SCD;
1029    AND = Mips::AND64;
1030    NOR = Mips::NOR64;
1031    ZERO = Mips::ZERO_64;
1032    BEQ = Mips::BEQ64;
1033  }
1034
1035  unsigned OldVal = MI->getOperand(0).getReg();
1036  unsigned Ptr = MI->getOperand(1).getReg();
1037  unsigned Incr = MI->getOperand(2).getReg();
1038
1039  unsigned StoreVal = RegInfo.createVirtualRegister(RC);
1040  unsigned AndRes = RegInfo.createVirtualRegister(RC);
1041  unsigned Success = RegInfo.createVirtualRegister(RC);
1042
1043  // insert new blocks after the current block
1044  const BasicBlock *LLVM_BB = BB->getBasicBlock();
1045  MachineBasicBlock *loopMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1046  MachineBasicBlock *exitMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1047  MachineFunction::iterator It = BB;
1048  ++It;
1049  MF->insert(It, loopMBB);
1050  MF->insert(It, exitMBB);
1051
1052  // Transfer the remainder of BB and its successor edges to exitMBB.
1053  exitMBB->splice(exitMBB->begin(), BB,
1054                  llvm::next(MachineBasicBlock::iterator(MI)),
1055                  BB->end());
1056  exitMBB->transferSuccessorsAndUpdatePHIs(BB);
1057
1058  //  thisMBB:
1059  //    ...
1060  //    fallthrough --> loopMBB
1061  BB->addSuccessor(loopMBB);
1062  loopMBB->addSuccessor(loopMBB);
1063  loopMBB->addSuccessor(exitMBB);
1064
1065  //  loopMBB:
1066  //    ll oldval, 0(ptr)
1067  //    <binop> storeval, oldval, incr
1068  //    sc success, storeval, 0(ptr)
1069  //    beq success, $0, loopMBB
1070  BB = loopMBB;
1071  BuildMI(BB, dl, TII->get(LL), OldVal).addReg(Ptr).addImm(0);
1072  if (Nand) {
1073    //  and andres, oldval, incr
1074    //  nor storeval, $0, andres
1075    BuildMI(BB, dl, TII->get(AND), AndRes).addReg(OldVal).addReg(Incr);
1076    BuildMI(BB, dl, TII->get(NOR), StoreVal).addReg(ZERO).addReg(AndRes);
1077  } else if (BinOpcode) {
1078    //  <binop> storeval, oldval, incr
1079    BuildMI(BB, dl, TII->get(BinOpcode), StoreVal).addReg(OldVal).addReg(Incr);
1080  } else {
1081    StoreVal = Incr;
1082  }
1083  BuildMI(BB, dl, TII->get(SC), Success).addReg(StoreVal).addReg(Ptr).addImm(0);
1084  BuildMI(BB, dl, TII->get(BEQ)).addReg(Success).addReg(ZERO).addMBB(loopMBB);
1085
1086  MI->eraseFromParent();   // The instruction is gone now.
1087
1088  return exitMBB;
1089}
1090
1091MachineBasicBlock *
1092MipsTargetLowering::EmitAtomicBinaryPartword(MachineInstr *MI,
1093                                             MachineBasicBlock *BB,
1094                                             unsigned Size, unsigned BinOpcode,
1095                                             bool Nand) const {
1096  assert((Size == 1 || Size == 2) &&
1097      "Unsupported size for EmitAtomicBinaryPartial.");
1098
1099  MachineFunction *MF = BB->getParent();
1100  MachineRegisterInfo &RegInfo = MF->getRegInfo();
1101  const TargetRegisterClass *RC = getRegClassFor(MVT::i32);
1102  const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
1103  DebugLoc dl = MI->getDebugLoc();
1104  unsigned LL = IsN64 ? Mips::LL_P8 : Mips::LL;
1105  unsigned SC = IsN64 ? Mips::SC_P8 : Mips::SC;
1106
1107  unsigned Dest = MI->getOperand(0).getReg();
1108  unsigned Ptr = MI->getOperand(1).getReg();
1109  unsigned Incr = MI->getOperand(2).getReg();
1110
1111  unsigned AlignedAddr = RegInfo.createVirtualRegister(RC);
1112  unsigned ShiftAmt = RegInfo.createVirtualRegister(RC);
1113  unsigned Mask = RegInfo.createVirtualRegister(RC);
1114  unsigned Mask2 = RegInfo.createVirtualRegister(RC);
1115  unsigned NewVal = RegInfo.createVirtualRegister(RC);
1116  unsigned OldVal = RegInfo.createVirtualRegister(RC);
1117  unsigned Incr2 = RegInfo.createVirtualRegister(RC);
1118  unsigned MaskLSB2 = RegInfo.createVirtualRegister(RC);
1119  unsigned PtrLSB2 = RegInfo.createVirtualRegister(RC);
1120  unsigned MaskUpper = RegInfo.createVirtualRegister(RC);
1121  unsigned AndRes = RegInfo.createVirtualRegister(RC);
1122  unsigned BinOpRes = RegInfo.createVirtualRegister(RC);
1123  unsigned MaskedOldVal0 = RegInfo.createVirtualRegister(RC);
1124  unsigned StoreVal = RegInfo.createVirtualRegister(RC);
1125  unsigned MaskedOldVal1 = RegInfo.createVirtualRegister(RC);
1126  unsigned SrlRes = RegInfo.createVirtualRegister(RC);
1127  unsigned SllRes = RegInfo.createVirtualRegister(RC);
1128  unsigned Success = RegInfo.createVirtualRegister(RC);
1129
1130  // insert new blocks after the current block
1131  const BasicBlock *LLVM_BB = BB->getBasicBlock();
1132  MachineBasicBlock *loopMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1133  MachineBasicBlock *sinkMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1134  MachineBasicBlock *exitMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1135  MachineFunction::iterator It = BB;
1136  ++It;
1137  MF->insert(It, loopMBB);
1138  MF->insert(It, sinkMBB);
1139  MF->insert(It, exitMBB);
1140
1141  // Transfer the remainder of BB and its successor edges to exitMBB.
1142  exitMBB->splice(exitMBB->begin(), BB,
1143                  llvm::next(MachineBasicBlock::iterator(MI)), BB->end());
1144  exitMBB->transferSuccessorsAndUpdatePHIs(BB);
1145
1146  BB->addSuccessor(loopMBB);
1147  loopMBB->addSuccessor(loopMBB);
1148  loopMBB->addSuccessor(sinkMBB);
1149  sinkMBB->addSuccessor(exitMBB);
1150
1151  //  thisMBB:
1152  //    addiu   masklsb2,$0,-4                # 0xfffffffc
1153  //    and     alignedaddr,ptr,masklsb2
1154  //    andi    ptrlsb2,ptr,3
1155  //    sll     shiftamt,ptrlsb2,3
1156  //    ori     maskupper,$0,255               # 0xff
1157  //    sll     mask,maskupper,shiftamt
1158  //    nor     mask2,$0,mask
1159  //    sll     incr2,incr,shiftamt
1160
1161  int64_t MaskImm = (Size == 1) ? 255 : 65535;
1162  BuildMI(BB, dl, TII->get(Mips::ADDiu), MaskLSB2)
1163    .addReg(Mips::ZERO).addImm(-4);
1164  BuildMI(BB, dl, TII->get(Mips::AND), AlignedAddr)
1165    .addReg(Ptr).addReg(MaskLSB2);
1166  BuildMI(BB, dl, TII->get(Mips::ANDi), PtrLSB2).addReg(Ptr).addImm(3);
1167  BuildMI(BB, dl, TII->get(Mips::SLL), ShiftAmt).addReg(PtrLSB2).addImm(3);
1168  BuildMI(BB, dl, TII->get(Mips::ORi), MaskUpper)
1169    .addReg(Mips::ZERO).addImm(MaskImm);
1170  BuildMI(BB, dl, TII->get(Mips::SLLV), Mask)
1171    .addReg(ShiftAmt).addReg(MaskUpper);
1172  BuildMI(BB, dl, TII->get(Mips::NOR), Mask2).addReg(Mips::ZERO).addReg(Mask);
1173  BuildMI(BB, dl, TII->get(Mips::SLLV), Incr2).addReg(ShiftAmt).addReg(Incr);
1174
1175  // atomic.load.binop
1176  // loopMBB:
1177  //   ll      oldval,0(alignedaddr)
1178  //   binop   binopres,oldval,incr2
1179  //   and     newval,binopres,mask
1180  //   and     maskedoldval0,oldval,mask2
1181  //   or      storeval,maskedoldval0,newval
1182  //   sc      success,storeval,0(alignedaddr)
1183  //   beq     success,$0,loopMBB
1184
1185  // atomic.swap
1186  // loopMBB:
1187  //   ll      oldval,0(alignedaddr)
1188  //   and     newval,incr2,mask
1189  //   and     maskedoldval0,oldval,mask2
1190  //   or      storeval,maskedoldval0,newval
1191  //   sc      success,storeval,0(alignedaddr)
1192  //   beq     success,$0,loopMBB
1193
1194  BB = loopMBB;
1195  BuildMI(BB, dl, TII->get(LL), OldVal).addReg(AlignedAddr).addImm(0);
1196  if (Nand) {
1197    //  and andres, oldval, incr2
1198    //  nor binopres, $0, andres
1199    //  and newval, binopres, mask
1200    BuildMI(BB, dl, TII->get(Mips::AND), AndRes).addReg(OldVal).addReg(Incr2);
1201    BuildMI(BB, dl, TII->get(Mips::NOR), BinOpRes)
1202      .addReg(Mips::ZERO).addReg(AndRes);
1203    BuildMI(BB, dl, TII->get(Mips::AND), NewVal).addReg(BinOpRes).addReg(Mask);
1204  } else if (BinOpcode) {
1205    //  <binop> binopres, oldval, incr2
1206    //  and newval, binopres, mask
1207    BuildMI(BB, dl, TII->get(BinOpcode), BinOpRes).addReg(OldVal).addReg(Incr2);
1208    BuildMI(BB, dl, TII->get(Mips::AND), NewVal).addReg(BinOpRes).addReg(Mask);
1209  } else {// atomic.swap
1210    //  and newval, incr2, mask
1211    BuildMI(BB, dl, TII->get(Mips::AND), NewVal).addReg(Incr2).addReg(Mask);
1212  }
1213
1214  BuildMI(BB, dl, TII->get(Mips::AND), MaskedOldVal0)
1215    .addReg(OldVal).addReg(Mask2);
1216  BuildMI(BB, dl, TII->get(Mips::OR), StoreVal)
1217    .addReg(MaskedOldVal0).addReg(NewVal);
1218  BuildMI(BB, dl, TII->get(SC), Success)
1219    .addReg(StoreVal).addReg(AlignedAddr).addImm(0);
1220  BuildMI(BB, dl, TII->get(Mips::BEQ))
1221    .addReg(Success).addReg(Mips::ZERO).addMBB(loopMBB);
1222
1223  //  sinkMBB:
1224  //    and     maskedoldval1,oldval,mask
1225  //    srl     srlres,maskedoldval1,shiftamt
1226  //    sll     sllres,srlres,24
1227  //    sra     dest,sllres,24
1228  BB = sinkMBB;
1229  int64_t ShiftImm = (Size == 1) ? 24 : 16;
1230
1231  BuildMI(BB, dl, TII->get(Mips::AND), MaskedOldVal1)
1232    .addReg(OldVal).addReg(Mask);
1233  BuildMI(BB, dl, TII->get(Mips::SRLV), SrlRes)
1234      .addReg(ShiftAmt).addReg(MaskedOldVal1);
1235  BuildMI(BB, dl, TII->get(Mips::SLL), SllRes)
1236      .addReg(SrlRes).addImm(ShiftImm);
1237  BuildMI(BB, dl, TII->get(Mips::SRA), Dest)
1238      .addReg(SllRes).addImm(ShiftImm);
1239
1240  MI->eraseFromParent();   // The instruction is gone now.
1241
1242  return exitMBB;
1243}
1244
1245MachineBasicBlock *
1246MipsTargetLowering::EmitAtomicCmpSwap(MachineInstr *MI,
1247                                      MachineBasicBlock *BB,
1248                                      unsigned Size) const {
1249  assert((Size == 4 || Size == 8) && "Unsupported size for EmitAtomicCmpSwap.");
1250
1251  MachineFunction *MF = BB->getParent();
1252  MachineRegisterInfo &RegInfo = MF->getRegInfo();
1253  const TargetRegisterClass *RC = getRegClassFor(MVT::getIntegerVT(Size * 8));
1254  const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
1255  DebugLoc dl = MI->getDebugLoc();
1256  unsigned LL, SC, ZERO, BNE, BEQ;
1257
1258  if (Size == 4) {
1259    LL = IsN64 ? Mips::LL_P8 : Mips::LL;
1260    SC = IsN64 ? Mips::SC_P8 : Mips::SC;
1261    ZERO = Mips::ZERO;
1262    BNE = Mips::BNE;
1263    BEQ = Mips::BEQ;
1264  }
1265  else {
1266    LL = IsN64 ? Mips::LLD_P8 : Mips::LLD;
1267    SC = IsN64 ? Mips::SCD_P8 : Mips::SCD;
1268    ZERO = Mips::ZERO_64;
1269    BNE = Mips::BNE64;
1270    BEQ = Mips::BEQ64;
1271  }
1272
1273  unsigned Dest    = MI->getOperand(0).getReg();
1274  unsigned Ptr     = MI->getOperand(1).getReg();
1275  unsigned OldVal  = MI->getOperand(2).getReg();
1276  unsigned NewVal  = MI->getOperand(3).getReg();
1277
1278  unsigned Success = RegInfo.createVirtualRegister(RC);
1279
1280  // insert new blocks after the current block
1281  const BasicBlock *LLVM_BB = BB->getBasicBlock();
1282  MachineBasicBlock *loop1MBB = MF->CreateMachineBasicBlock(LLVM_BB);
1283  MachineBasicBlock *loop2MBB = MF->CreateMachineBasicBlock(LLVM_BB);
1284  MachineBasicBlock *exitMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1285  MachineFunction::iterator It = BB;
1286  ++It;
1287  MF->insert(It, loop1MBB);
1288  MF->insert(It, loop2MBB);
1289  MF->insert(It, exitMBB);
1290
1291  // Transfer the remainder of BB and its successor edges to exitMBB.
1292  exitMBB->splice(exitMBB->begin(), BB,
1293                  llvm::next(MachineBasicBlock::iterator(MI)), BB->end());
1294  exitMBB->transferSuccessorsAndUpdatePHIs(BB);
1295
1296  //  thisMBB:
1297  //    ...
1298  //    fallthrough --> loop1MBB
1299  BB->addSuccessor(loop1MBB);
1300  loop1MBB->addSuccessor(exitMBB);
1301  loop1MBB->addSuccessor(loop2MBB);
1302  loop2MBB->addSuccessor(loop1MBB);
1303  loop2MBB->addSuccessor(exitMBB);
1304
1305  // loop1MBB:
1306  //   ll dest, 0(ptr)
1307  //   bne dest, oldval, exitMBB
1308  BB = loop1MBB;
1309  BuildMI(BB, dl, TII->get(LL), Dest).addReg(Ptr).addImm(0);
1310  BuildMI(BB, dl, TII->get(BNE))
1311    .addReg(Dest).addReg(OldVal).addMBB(exitMBB);
1312
1313  // loop2MBB:
1314  //   sc success, newval, 0(ptr)
1315  //   beq success, $0, loop1MBB
1316  BB = loop2MBB;
1317  BuildMI(BB, dl, TII->get(SC), Success)
1318    .addReg(NewVal).addReg(Ptr).addImm(0);
1319  BuildMI(BB, dl, TII->get(BEQ))
1320    .addReg(Success).addReg(ZERO).addMBB(loop1MBB);
1321
1322  MI->eraseFromParent();   // The instruction is gone now.
1323
1324  return exitMBB;
1325}
1326
1327MachineBasicBlock *
1328MipsTargetLowering::EmitAtomicCmpSwapPartword(MachineInstr *MI,
1329                                              MachineBasicBlock *BB,
1330                                              unsigned Size) const {
1331  assert((Size == 1 || Size == 2) &&
1332      "Unsupported size for EmitAtomicCmpSwapPartial.");
1333
1334  MachineFunction *MF = BB->getParent();
1335  MachineRegisterInfo &RegInfo = MF->getRegInfo();
1336  const TargetRegisterClass *RC = getRegClassFor(MVT::i32);
1337  const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
1338  DebugLoc dl = MI->getDebugLoc();
1339  unsigned LL = IsN64 ? Mips::LL_P8 : Mips::LL;
1340  unsigned SC = IsN64 ? Mips::SC_P8 : Mips::SC;
1341
1342  unsigned Dest    = MI->getOperand(0).getReg();
1343  unsigned Ptr     = MI->getOperand(1).getReg();
1344  unsigned CmpVal  = MI->getOperand(2).getReg();
1345  unsigned NewVal  = MI->getOperand(3).getReg();
1346
1347  unsigned AlignedAddr = RegInfo.createVirtualRegister(RC);
1348  unsigned ShiftAmt = RegInfo.createVirtualRegister(RC);
1349  unsigned Mask = RegInfo.createVirtualRegister(RC);
1350  unsigned Mask2 = RegInfo.createVirtualRegister(RC);
1351  unsigned ShiftedCmpVal = RegInfo.createVirtualRegister(RC);
1352  unsigned OldVal = RegInfo.createVirtualRegister(RC);
1353  unsigned MaskedOldVal0 = RegInfo.createVirtualRegister(RC);
1354  unsigned ShiftedNewVal = RegInfo.createVirtualRegister(RC);
1355  unsigned MaskLSB2 = RegInfo.createVirtualRegister(RC);
1356  unsigned PtrLSB2 = RegInfo.createVirtualRegister(RC);
1357  unsigned MaskUpper = RegInfo.createVirtualRegister(RC);
1358  unsigned MaskedCmpVal = RegInfo.createVirtualRegister(RC);
1359  unsigned MaskedNewVal = RegInfo.createVirtualRegister(RC);
1360  unsigned MaskedOldVal1 = RegInfo.createVirtualRegister(RC);
1361  unsigned StoreVal = RegInfo.createVirtualRegister(RC);
1362  unsigned SrlRes = RegInfo.createVirtualRegister(RC);
1363  unsigned SllRes = RegInfo.createVirtualRegister(RC);
1364  unsigned Success = RegInfo.createVirtualRegister(RC);
1365
1366  // insert new blocks after the current block
1367  const BasicBlock *LLVM_BB = BB->getBasicBlock();
1368  MachineBasicBlock *loop1MBB = MF->CreateMachineBasicBlock(LLVM_BB);
1369  MachineBasicBlock *loop2MBB = MF->CreateMachineBasicBlock(LLVM_BB);
1370  MachineBasicBlock *sinkMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1371  MachineBasicBlock *exitMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1372  MachineFunction::iterator It = BB;
1373  ++It;
1374  MF->insert(It, loop1MBB);
1375  MF->insert(It, loop2MBB);
1376  MF->insert(It, sinkMBB);
1377  MF->insert(It, exitMBB);
1378
1379  // Transfer the remainder of BB and its successor edges to exitMBB.
1380  exitMBB->splice(exitMBB->begin(), BB,
1381                  llvm::next(MachineBasicBlock::iterator(MI)), BB->end());
1382  exitMBB->transferSuccessorsAndUpdatePHIs(BB);
1383
1384  BB->addSuccessor(loop1MBB);
1385  loop1MBB->addSuccessor(sinkMBB);
1386  loop1MBB->addSuccessor(loop2MBB);
1387  loop2MBB->addSuccessor(loop1MBB);
1388  loop2MBB->addSuccessor(sinkMBB);
1389  sinkMBB->addSuccessor(exitMBB);
1390
1391  // FIXME: computation of newval2 can be moved to loop2MBB.
1392  //  thisMBB:
1393  //    addiu   masklsb2,$0,-4                # 0xfffffffc
1394  //    and     alignedaddr,ptr,masklsb2
1395  //    andi    ptrlsb2,ptr,3
1396  //    sll     shiftamt,ptrlsb2,3
1397  //    ori     maskupper,$0,255               # 0xff
1398  //    sll     mask,maskupper,shiftamt
1399  //    nor     mask2,$0,mask
1400  //    andi    maskedcmpval,cmpval,255
1401  //    sll     shiftedcmpval,maskedcmpval,shiftamt
1402  //    andi    maskednewval,newval,255
1403  //    sll     shiftednewval,maskednewval,shiftamt
1404  int64_t MaskImm = (Size == 1) ? 255 : 65535;
1405  BuildMI(BB, dl, TII->get(Mips::ADDiu), MaskLSB2)
1406    .addReg(Mips::ZERO).addImm(-4);
1407  BuildMI(BB, dl, TII->get(Mips::AND), AlignedAddr)
1408    .addReg(Ptr).addReg(MaskLSB2);
1409  BuildMI(BB, dl, TII->get(Mips::ANDi), PtrLSB2).addReg(Ptr).addImm(3);
1410  BuildMI(BB, dl, TII->get(Mips::SLL), ShiftAmt).addReg(PtrLSB2).addImm(3);
1411  BuildMI(BB, dl, TII->get(Mips::ORi), MaskUpper)
1412    .addReg(Mips::ZERO).addImm(MaskImm);
1413  BuildMI(BB, dl, TII->get(Mips::SLLV), Mask)
1414    .addReg(ShiftAmt).addReg(MaskUpper);
1415  BuildMI(BB, dl, TII->get(Mips::NOR), Mask2).addReg(Mips::ZERO).addReg(Mask);
1416  BuildMI(BB, dl, TII->get(Mips::ANDi), MaskedCmpVal)
1417    .addReg(CmpVal).addImm(MaskImm);
1418  BuildMI(BB, dl, TII->get(Mips::SLLV), ShiftedCmpVal)
1419    .addReg(ShiftAmt).addReg(MaskedCmpVal);
1420  BuildMI(BB, dl, TII->get(Mips::ANDi), MaskedNewVal)
1421    .addReg(NewVal).addImm(MaskImm);
1422  BuildMI(BB, dl, TII->get(Mips::SLLV), ShiftedNewVal)
1423    .addReg(ShiftAmt).addReg(MaskedNewVal);
1424
1425  //  loop1MBB:
1426  //    ll      oldval,0(alginedaddr)
1427  //    and     maskedoldval0,oldval,mask
1428  //    bne     maskedoldval0,shiftedcmpval,sinkMBB
1429  BB = loop1MBB;
1430  BuildMI(BB, dl, TII->get(LL), OldVal).addReg(AlignedAddr).addImm(0);
1431  BuildMI(BB, dl, TII->get(Mips::AND), MaskedOldVal0)
1432    .addReg(OldVal).addReg(Mask);
1433  BuildMI(BB, dl, TII->get(Mips::BNE))
1434    .addReg(MaskedOldVal0).addReg(ShiftedCmpVal).addMBB(sinkMBB);
1435
1436  //  loop2MBB:
1437  //    and     maskedoldval1,oldval,mask2
1438  //    or      storeval,maskedoldval1,shiftednewval
1439  //    sc      success,storeval,0(alignedaddr)
1440  //    beq     success,$0,loop1MBB
1441  BB = loop2MBB;
1442  BuildMI(BB, dl, TII->get(Mips::AND), MaskedOldVal1)
1443    .addReg(OldVal).addReg(Mask2);
1444  BuildMI(BB, dl, TII->get(Mips::OR), StoreVal)
1445    .addReg(MaskedOldVal1).addReg(ShiftedNewVal);
1446  BuildMI(BB, dl, TII->get(SC), Success)
1447      .addReg(StoreVal).addReg(AlignedAddr).addImm(0);
1448  BuildMI(BB, dl, TII->get(Mips::BEQ))
1449      .addReg(Success).addReg(Mips::ZERO).addMBB(loop1MBB);
1450
1451  //  sinkMBB:
1452  //    srl     srlres,maskedoldval0,shiftamt
1453  //    sll     sllres,srlres,24
1454  //    sra     dest,sllres,24
1455  BB = sinkMBB;
1456  int64_t ShiftImm = (Size == 1) ? 24 : 16;
1457
1458  BuildMI(BB, dl, TII->get(Mips::SRLV), SrlRes)
1459      .addReg(ShiftAmt).addReg(MaskedOldVal0);
1460  BuildMI(BB, dl, TII->get(Mips::SLL), SllRes)
1461      .addReg(SrlRes).addImm(ShiftImm);
1462  BuildMI(BB, dl, TII->get(Mips::SRA), Dest)
1463      .addReg(SllRes).addImm(ShiftImm);
1464
1465  MI->eraseFromParent();   // The instruction is gone now.
1466
1467  return exitMBB;
1468}
1469
1470//===----------------------------------------------------------------------===//
1471//  Misc Lower Operation implementation
1472//===----------------------------------------------------------------------===//
1473SDValue MipsTargetLowering::
1474LowerDYNAMIC_STACKALLOC(SDValue Op, SelectionDAG &DAG) const
1475{
1476  MachineFunction &MF = DAG.getMachineFunction();
1477  MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
1478  unsigned SP = IsN64 ? Mips::SP_64 : Mips::SP;
1479
1480  assert(getTargetMachine().getFrameLowering()->getStackAlignment() >=
1481         cast<ConstantSDNode>(Op.getOperand(2).getNode())->getZExtValue() &&
1482         "Cannot lower if the alignment of the allocated space is larger than \
1483          that of the stack.");
1484
1485  SDValue Chain = Op.getOperand(0);
1486  SDValue Size = Op.getOperand(1);
1487  DebugLoc dl = Op.getDebugLoc();
1488
1489  // Get a reference from Mips stack pointer
1490  SDValue StackPointer = DAG.getCopyFromReg(Chain, dl, SP, getPointerTy());
1491
1492  // Subtract the dynamic size from the actual stack size to
1493  // obtain the new stack size.
1494  SDValue Sub = DAG.getNode(ISD::SUB, dl, getPointerTy(), StackPointer, Size);
1495
1496  // The Sub result contains the new stack start address, so it
1497  // must be placed in the stack pointer register.
1498  Chain = DAG.getCopyToReg(StackPointer.getValue(1), dl, SP, Sub, SDValue());
1499
1500  // This node always has two return values: a new stack pointer
1501  // value and a chain
1502  SDVTList VTLs = DAG.getVTList(getPointerTy(), MVT::Other);
1503  SDValue Ptr = DAG.getFrameIndex(MipsFI->getDynAllocFI(), getPointerTy());
1504  SDValue Ops[] = { Chain, Ptr, Chain.getValue(1) };
1505
1506  return DAG.getNode(MipsISD::DynAlloc, dl, VTLs, Ops, 3);
1507}
1508
1509SDValue MipsTargetLowering::
1510LowerBRCOND(SDValue Op, SelectionDAG &DAG) const
1511{
1512  // The first operand is the chain, the second is the condition, the third is
1513  // the block to branch to if the condition is true.
1514  SDValue Chain = Op.getOperand(0);
1515  SDValue Dest = Op.getOperand(2);
1516  DebugLoc dl = Op.getDebugLoc();
1517
1518  SDValue CondRes = CreateFPCmp(DAG, Op.getOperand(1));
1519
1520  // Return if flag is not set by a floating point comparison.
1521  if (CondRes.getOpcode() != MipsISD::FPCmp)
1522    return Op;
1523
1524  SDValue CCNode  = CondRes.getOperand(2);
1525  Mips::CondCode CC =
1526    (Mips::CondCode)cast<ConstantSDNode>(CCNode)->getZExtValue();
1527  SDValue BrCode = DAG.getConstant(GetFPBranchCodeFromCond(CC), MVT::i32);
1528
1529  return DAG.getNode(MipsISD::FPBrcond, dl, Op.getValueType(), Chain, BrCode,
1530                     Dest, CondRes);
1531}
1532
1533SDValue MipsTargetLowering::
1534LowerSELECT(SDValue Op, SelectionDAG &DAG) const
1535{
1536  SDValue Cond = CreateFPCmp(DAG, Op.getOperand(0));
1537
1538  // Return if flag is not set by a floating point comparison.
1539  if (Cond.getOpcode() != MipsISD::FPCmp)
1540    return Op;
1541
1542  return CreateCMovFP(DAG, Cond, Op.getOperand(1), Op.getOperand(2),
1543                      Op.getDebugLoc());
1544}
1545
1546SDValue MipsTargetLowering::LowerSETCC(SDValue Op, SelectionDAG &DAG) const {
1547  SDValue Cond = CreateFPCmp(DAG, Op);
1548
1549  assert(Cond.getOpcode() == MipsISD::FPCmp &&
1550         "Floating point operand expected.");
1551
1552  SDValue True  = DAG.getConstant(1, MVT::i32);
1553  SDValue False = DAG.getConstant(0, MVT::i32);
1554
1555  return CreateCMovFP(DAG, Cond, True, False, Op.getDebugLoc());
1556}
1557
1558SDValue MipsTargetLowering::LowerGlobalAddress(SDValue Op,
1559                                               SelectionDAG &DAG) const {
1560  // FIXME there isn't actually debug info here
1561  DebugLoc dl = Op.getDebugLoc();
1562  const GlobalValue *GV = cast<GlobalAddressSDNode>(Op)->getGlobal();
1563
1564  if (getTargetMachine().getRelocationModel() != Reloc::PIC_ && !IsN64) {
1565    SDVTList VTs = DAG.getVTList(MVT::i32);
1566
1567    MipsTargetObjectFile &TLOF = (MipsTargetObjectFile&)getObjFileLowering();
1568
1569    // %gp_rel relocation
1570    if (TLOF.IsGlobalInSmallSection(GV, getTargetMachine())) {
1571      SDValue GA = DAG.getTargetGlobalAddress(GV, dl, MVT::i32, 0,
1572                                              MipsII::MO_GPREL);
1573      SDValue GPRelNode = DAG.getNode(MipsISD::GPRel, dl, VTs, &GA, 1);
1574      SDValue GOT = DAG.getGLOBAL_OFFSET_TABLE(MVT::i32);
1575      return DAG.getNode(ISD::ADD, dl, MVT::i32, GOT, GPRelNode);
1576    }
1577    // %hi/%lo relocation
1578    SDValue GAHi = DAG.getTargetGlobalAddress(GV, dl, MVT::i32, 0,
1579                                              MipsII::MO_ABS_HI);
1580    SDValue GALo = DAG.getTargetGlobalAddress(GV, dl, MVT::i32, 0,
1581                                              MipsII::MO_ABS_LO);
1582    SDValue HiPart = DAG.getNode(MipsISD::Hi, dl, VTs, &GAHi, 1);
1583    SDValue Lo = DAG.getNode(MipsISD::Lo, dl, MVT::i32, GALo);
1584    return DAG.getNode(ISD::ADD, dl, MVT::i32, HiPart, Lo);
1585  }
1586
1587  EVT ValTy = Op.getValueType();
1588  bool HasGotOfst = (GV->hasInternalLinkage() ||
1589                     (GV->hasLocalLinkage() && !isa<Function>(GV)));
1590  unsigned GotFlag = HasMips64 ?
1591                     (HasGotOfst ? MipsII::MO_GOT_PAGE : MipsII::MO_GOT_DISP) :
1592                     (HasGotOfst ? MipsII::MO_GOT : MipsII::MO_GOT16);
1593  SDValue GA = DAG.getTargetGlobalAddress(GV, dl, ValTy, 0, GotFlag);
1594  GA = DAG.getNode(MipsISD::Wrapper, dl, ValTy, GetGlobalReg(DAG, ValTy), GA);
1595  SDValue ResNode = DAG.getLoad(ValTy, dl, DAG.getEntryNode(), GA,
1596                                MachinePointerInfo(), false, false, false, 0);
1597  // On functions and global targets not internal linked only
1598  // a load from got/GP is necessary for PIC to work.
1599  if (!HasGotOfst)
1600    return ResNode;
1601  SDValue GALo = DAG.getTargetGlobalAddress(GV, dl, ValTy, 0,
1602                                            HasMips64 ? MipsII::MO_GOT_OFST :
1603                                                        MipsII::MO_ABS_LO);
1604  SDValue Lo = DAG.getNode(MipsISD::Lo, dl, ValTy, GALo);
1605  return DAG.getNode(ISD::ADD, dl, ValTy, ResNode, Lo);
1606}
1607
1608SDValue MipsTargetLowering::LowerBlockAddress(SDValue Op,
1609                                              SelectionDAG &DAG) const {
1610  const BlockAddress *BA = cast<BlockAddressSDNode>(Op)->getBlockAddress();
1611  // FIXME there isn't actually debug info here
1612  DebugLoc dl = Op.getDebugLoc();
1613
1614  if (getTargetMachine().getRelocationModel() != Reloc::PIC_ && !IsN64) {
1615    // %hi/%lo relocation
1616    SDValue BAHi = DAG.getBlockAddress(BA, MVT::i32, true, MipsII::MO_ABS_HI);
1617    SDValue BALo = DAG.getBlockAddress(BA, MVT::i32, true, MipsII::MO_ABS_LO);
1618    SDValue Hi = DAG.getNode(MipsISD::Hi, dl, MVT::i32, BAHi);
1619    SDValue Lo = DAG.getNode(MipsISD::Lo, dl, MVT::i32, BALo);
1620    return DAG.getNode(ISD::ADD, dl, MVT::i32, Hi, Lo);
1621  }
1622
1623  EVT ValTy = Op.getValueType();
1624  unsigned GOTFlag = HasMips64 ? MipsII::MO_GOT_PAGE : MipsII::MO_GOT;
1625  unsigned OFSTFlag = HasMips64 ? MipsII::MO_GOT_OFST : MipsII::MO_ABS_LO;
1626  SDValue BAGOTOffset = DAG.getBlockAddress(BA, ValTy, true, GOTFlag);
1627  BAGOTOffset = DAG.getNode(MipsISD::Wrapper, dl, ValTy,
1628                            GetGlobalReg(DAG, ValTy), BAGOTOffset);
1629  SDValue BALOOffset = DAG.getBlockAddress(BA, ValTy, true, OFSTFlag);
1630  SDValue Load = DAG.getLoad(ValTy, dl, DAG.getEntryNode(), BAGOTOffset,
1631                             MachinePointerInfo(), false, false, false, 0);
1632  SDValue Lo = DAG.getNode(MipsISD::Lo, dl, ValTy, BALOOffset);
1633  return DAG.getNode(ISD::ADD, dl, ValTy, Load, Lo);
1634}
1635
1636SDValue MipsTargetLowering::
1637LowerGlobalTLSAddress(SDValue Op, SelectionDAG &DAG) const
1638{
1639  // If the relocation model is PIC, use the General Dynamic TLS Model or
1640  // Local Dynamic TLS model, otherwise use the Initial Exec or
1641  // Local Exec TLS Model.
1642
1643  GlobalAddressSDNode *GA = cast<GlobalAddressSDNode>(Op);
1644  DebugLoc dl = GA->getDebugLoc();
1645  const GlobalValue *GV = GA->getGlobal();
1646  EVT PtrVT = getPointerTy();
1647
1648  TLSModel::Model model = getTargetMachine().getTLSModel(GV);
1649
1650  if (model == TLSModel::GeneralDynamic || model == TLSModel::LocalDynamic) {
1651    // General Dynamic and Local Dynamic TLS Model.
1652    unsigned Flag = (model == TLSModel::LocalDynamic) ? MipsII::MO_TLSLDM
1653                                                      : MipsII::MO_TLSGD;
1654
1655    SDValue TGA = DAG.getTargetGlobalAddress(GV, dl, PtrVT, 0, Flag);
1656    SDValue Argument = DAG.getNode(MipsISD::Wrapper, dl, PtrVT,
1657                                   GetGlobalReg(DAG, PtrVT), TGA);
1658    unsigned PtrSize = PtrVT.getSizeInBits();
1659    IntegerType *PtrTy = Type::getIntNTy(*DAG.getContext(), PtrSize);
1660
1661    SDValue TlsGetAddr = DAG.getExternalSymbol("__tls_get_addr", PtrVT);
1662
1663    ArgListTy Args;
1664    ArgListEntry Entry;
1665    Entry.Node = Argument;
1666    Entry.Ty = PtrTy;
1667    Args.push_back(Entry);
1668
1669    TargetLowering::CallLoweringInfo CLI(DAG.getEntryNode(), PtrTy,
1670                  false, false, false, false, 0, CallingConv::C,
1671                  /*isTailCall=*/false, /*doesNotRet=*/false,
1672                  /*isReturnValueUsed=*/true,
1673                  TlsGetAddr, Args, DAG, dl);
1674    std::pair<SDValue, SDValue> CallResult = LowerCallTo(CLI);
1675
1676    SDValue Ret = CallResult.first;
1677
1678    if (model != TLSModel::LocalDynamic)
1679      return Ret;
1680
1681    SDValue TGAHi = DAG.getTargetGlobalAddress(GV, dl, PtrVT, 0,
1682                                               MipsII::MO_DTPREL_HI);
1683    SDValue Hi = DAG.getNode(MipsISD::Hi, dl, PtrVT, TGAHi);
1684    SDValue TGALo = DAG.getTargetGlobalAddress(GV, dl, PtrVT, 0,
1685                                               MipsII::MO_DTPREL_LO);
1686    SDValue Lo = DAG.getNode(MipsISD::Lo, dl, PtrVT, TGALo);
1687    SDValue Add = DAG.getNode(ISD::ADD, dl, PtrVT, Hi, Ret);
1688    return DAG.getNode(ISD::ADD, dl, PtrVT, Add, Lo);
1689  }
1690
1691  SDValue Offset;
1692  if (model == TLSModel::InitialExec) {
1693    // Initial Exec TLS Model
1694    SDValue TGA = DAG.getTargetGlobalAddress(GV, dl, PtrVT, 0,
1695                                             MipsII::MO_GOTTPREL);
1696    TGA = DAG.getNode(MipsISD::Wrapper, dl, PtrVT, GetGlobalReg(DAG, PtrVT),
1697                      TGA);
1698    Offset = DAG.getLoad(PtrVT, dl,
1699                         DAG.getEntryNode(), TGA, MachinePointerInfo(),
1700                         false, false, false, 0);
1701  } else {
1702    // Local Exec TLS Model
1703    assert(model == TLSModel::LocalExec);
1704    SDValue TGAHi = DAG.getTargetGlobalAddress(GV, dl, PtrVT, 0,
1705                                               MipsII::MO_TPREL_HI);
1706    SDValue TGALo = DAG.getTargetGlobalAddress(GV, dl, PtrVT, 0,
1707                                               MipsII::MO_TPREL_LO);
1708    SDValue Hi = DAG.getNode(MipsISD::Hi, dl, PtrVT, TGAHi);
1709    SDValue Lo = DAG.getNode(MipsISD::Lo, dl, PtrVT, TGALo);
1710    Offset = DAG.getNode(ISD::ADD, dl, PtrVT, Hi, Lo);
1711  }
1712
1713  SDValue ThreadPointer = DAG.getNode(MipsISD::ThreadPointer, dl, PtrVT);
1714  return DAG.getNode(ISD::ADD, dl, PtrVT, ThreadPointer, Offset);
1715}
1716
1717SDValue MipsTargetLowering::
1718LowerJumpTable(SDValue Op, SelectionDAG &DAG) const
1719{
1720  SDValue HiPart, JTI, JTILo;
1721  // FIXME there isn't actually debug info here
1722  DebugLoc dl = Op.getDebugLoc();
1723  bool IsPIC = getTargetMachine().getRelocationModel() == Reloc::PIC_;
1724  EVT PtrVT = Op.getValueType();
1725  JumpTableSDNode *JT = cast<JumpTableSDNode>(Op);
1726
1727  if (!IsPIC && !IsN64) {
1728    JTI = DAG.getTargetJumpTable(JT->getIndex(), PtrVT, MipsII::MO_ABS_HI);
1729    HiPart = DAG.getNode(MipsISD::Hi, dl, PtrVT, JTI);
1730    JTILo = DAG.getTargetJumpTable(JT->getIndex(), PtrVT, MipsII::MO_ABS_LO);
1731  } else {// Emit Load from Global Pointer
1732    unsigned GOTFlag = HasMips64 ? MipsII::MO_GOT_PAGE : MipsII::MO_GOT;
1733    unsigned OfstFlag = HasMips64 ? MipsII::MO_GOT_OFST : MipsII::MO_ABS_LO;
1734    JTI = DAG.getTargetJumpTable(JT->getIndex(), PtrVT, GOTFlag);
1735    JTI = DAG.getNode(MipsISD::Wrapper, dl, PtrVT, GetGlobalReg(DAG, PtrVT),
1736                      JTI);
1737    HiPart = DAG.getLoad(PtrVT, dl, DAG.getEntryNode(), JTI,
1738                         MachinePointerInfo(), false, false, false, 0);
1739    JTILo = DAG.getTargetJumpTable(JT->getIndex(), PtrVT, OfstFlag);
1740  }
1741
1742  SDValue Lo = DAG.getNode(MipsISD::Lo, dl, PtrVT, JTILo);
1743  return DAG.getNode(ISD::ADD, dl, PtrVT, HiPart, Lo);
1744}
1745
1746SDValue MipsTargetLowering::
1747LowerConstantPool(SDValue Op, SelectionDAG &DAG) const
1748{
1749  SDValue ResNode;
1750  ConstantPoolSDNode *N = cast<ConstantPoolSDNode>(Op);
1751  const Constant *C = N->getConstVal();
1752  // FIXME there isn't actually debug info here
1753  DebugLoc dl = Op.getDebugLoc();
1754
1755  // gp_rel relocation
1756  // FIXME: we should reference the constant pool using small data sections,
1757  // but the asm printer currently doesn't support this feature without
1758  // hacking it. This feature should come soon so we can uncomment the
1759  // stuff below.
1760  //if (IsInSmallSection(C->getType())) {
1761  //  SDValue GPRelNode = DAG.getNode(MipsISD::GPRel, MVT::i32, CP);
1762  //  SDValue GOT = DAG.getGLOBAL_OFFSET_TABLE(MVT::i32);
1763  //  ResNode = DAG.getNode(ISD::ADD, MVT::i32, GOT, GPRelNode);
1764
1765  if (getTargetMachine().getRelocationModel() != Reloc::PIC_ && !IsN64) {
1766    SDValue CPHi = DAG.getTargetConstantPool(C, MVT::i32, N->getAlignment(),
1767                                             N->getOffset(), MipsII::MO_ABS_HI);
1768    SDValue CPLo = DAG.getTargetConstantPool(C, MVT::i32, N->getAlignment(),
1769                                             N->getOffset(), MipsII::MO_ABS_LO);
1770    SDValue HiPart = DAG.getNode(MipsISD::Hi, dl, MVT::i32, CPHi);
1771    SDValue Lo = DAG.getNode(MipsISD::Lo, dl, MVT::i32, CPLo);
1772    ResNode = DAG.getNode(ISD::ADD, dl, MVT::i32, HiPart, Lo);
1773  } else {
1774    EVT ValTy = Op.getValueType();
1775    unsigned GOTFlag = HasMips64 ? MipsII::MO_GOT_PAGE : MipsII::MO_GOT;
1776    unsigned OFSTFlag = HasMips64 ? MipsII::MO_GOT_OFST : MipsII::MO_ABS_LO;
1777    SDValue CP = DAG.getTargetConstantPool(C, ValTy, N->getAlignment(),
1778                                           N->getOffset(), GOTFlag);
1779    CP = DAG.getNode(MipsISD::Wrapper, dl, ValTy, GetGlobalReg(DAG, ValTy), CP);
1780    SDValue Load = DAG.getLoad(ValTy, dl, DAG.getEntryNode(), CP,
1781                               MachinePointerInfo::getConstantPool(), false,
1782                               false, false, 0);
1783    SDValue CPLo = DAG.getTargetConstantPool(C, ValTy, N->getAlignment(),
1784                                             N->getOffset(), OFSTFlag);
1785    SDValue Lo = DAG.getNode(MipsISD::Lo, dl, ValTy, CPLo);
1786    ResNode = DAG.getNode(ISD::ADD, dl, ValTy, Load, Lo);
1787  }
1788
1789  return ResNode;
1790}
1791
1792SDValue MipsTargetLowering::LowerVASTART(SDValue Op, SelectionDAG &DAG) const {
1793  MachineFunction &MF = DAG.getMachineFunction();
1794  MipsFunctionInfo *FuncInfo = MF.getInfo<MipsFunctionInfo>();
1795
1796  DebugLoc dl = Op.getDebugLoc();
1797  SDValue FI = DAG.getFrameIndex(FuncInfo->getVarArgsFrameIndex(),
1798                                 getPointerTy());
1799
1800  // vastart just stores the address of the VarArgsFrameIndex slot into the
1801  // memory location argument.
1802  const Value *SV = cast<SrcValueSDNode>(Op.getOperand(2))->getValue();
1803  return DAG.getStore(Op.getOperand(0), dl, FI, Op.getOperand(1),
1804                      MachinePointerInfo(SV), false, false, 0);
1805}
1806
1807static SDValue LowerFCOPYSIGN32(SDValue Op, SelectionDAG &DAG, bool HasR2) {
1808  EVT TyX = Op.getOperand(0).getValueType();
1809  EVT TyY = Op.getOperand(1).getValueType();
1810  SDValue Const1 = DAG.getConstant(1, MVT::i32);
1811  SDValue Const31 = DAG.getConstant(31, MVT::i32);
1812  DebugLoc DL = Op.getDebugLoc();
1813  SDValue Res;
1814
1815  // If operand is of type f64, extract the upper 32-bit. Otherwise, bitcast it
1816  // to i32.
1817  SDValue X = (TyX == MVT::f32) ?
1818    DAG.getNode(ISD::BITCAST, DL, MVT::i32, Op.getOperand(0)) :
1819    DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32, Op.getOperand(0),
1820                Const1);
1821  SDValue Y = (TyY == MVT::f32) ?
1822    DAG.getNode(ISD::BITCAST, DL, MVT::i32, Op.getOperand(1)) :
1823    DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32, Op.getOperand(1),
1824                Const1);
1825
1826  if (HasR2) {
1827    // ext  E, Y, 31, 1  ; extract bit31 of Y
1828    // ins  X, E, 31, 1  ; insert extracted bit at bit31 of X
1829    SDValue E = DAG.getNode(MipsISD::Ext, DL, MVT::i32, Y, Const31, Const1);
1830    Res = DAG.getNode(MipsISD::Ins, DL, MVT::i32, E, Const31, Const1, X);
1831  } else {
1832    // sll SllX, X, 1
1833    // srl SrlX, SllX, 1
1834    // srl SrlY, Y, 31
1835    // sll SllY, SrlX, 31
1836    // or  Or, SrlX, SllY
1837    SDValue SllX = DAG.getNode(ISD::SHL, DL, MVT::i32, X, Const1);
1838    SDValue SrlX = DAG.getNode(ISD::SRL, DL, MVT::i32, SllX, Const1);
1839    SDValue SrlY = DAG.getNode(ISD::SRL, DL, MVT::i32, Y, Const31);
1840    SDValue SllY = DAG.getNode(ISD::SHL, DL, MVT::i32, SrlY, Const31);
1841    Res = DAG.getNode(ISD::OR, DL, MVT::i32, SrlX, SllY);
1842  }
1843
1844  if (TyX == MVT::f32)
1845    return DAG.getNode(ISD::BITCAST, DL, Op.getOperand(0).getValueType(), Res);
1846
1847  SDValue LowX = DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32,
1848                             Op.getOperand(0), DAG.getConstant(0, MVT::i32));
1849  return DAG.getNode(MipsISD::BuildPairF64, DL, MVT::f64, LowX, Res);
1850}
1851
1852static SDValue LowerFCOPYSIGN64(SDValue Op, SelectionDAG &DAG, bool HasR2) {
1853  unsigned WidthX = Op.getOperand(0).getValueSizeInBits();
1854  unsigned WidthY = Op.getOperand(1).getValueSizeInBits();
1855  EVT TyX = MVT::getIntegerVT(WidthX), TyY = MVT::getIntegerVT(WidthY);
1856  SDValue Const1 = DAG.getConstant(1, MVT::i32);
1857  DebugLoc DL = Op.getDebugLoc();
1858
1859  // Bitcast to integer nodes.
1860  SDValue X = DAG.getNode(ISD::BITCAST, DL, TyX, Op.getOperand(0));
1861  SDValue Y = DAG.getNode(ISD::BITCAST, DL, TyY, Op.getOperand(1));
1862
1863  if (HasR2) {
1864    // ext  E, Y, width(Y) - 1, 1  ; extract bit width(Y)-1 of Y
1865    // ins  X, E, width(X) - 1, 1  ; insert extracted bit at bit width(X)-1 of X
1866    SDValue E = DAG.getNode(MipsISD::Ext, DL, TyY, Y,
1867                            DAG.getConstant(WidthY - 1, MVT::i32), Const1);
1868
1869    if (WidthX > WidthY)
1870      E = DAG.getNode(ISD::ZERO_EXTEND, DL, TyX, E);
1871    else if (WidthY > WidthX)
1872      E = DAG.getNode(ISD::TRUNCATE, DL, TyX, E);
1873
1874    SDValue I = DAG.getNode(MipsISD::Ins, DL, TyX, E,
1875                            DAG.getConstant(WidthX - 1, MVT::i32), Const1, X);
1876    return DAG.getNode(ISD::BITCAST, DL, Op.getOperand(0).getValueType(), I);
1877  }
1878
1879  // (d)sll SllX, X, 1
1880  // (d)srl SrlX, SllX, 1
1881  // (d)srl SrlY, Y, width(Y)-1
1882  // (d)sll SllY, SrlX, width(Y)-1
1883  // or     Or, SrlX, SllY
1884  SDValue SllX = DAG.getNode(ISD::SHL, DL, TyX, X, Const1);
1885  SDValue SrlX = DAG.getNode(ISD::SRL, DL, TyX, SllX, Const1);
1886  SDValue SrlY = DAG.getNode(ISD::SRL, DL, TyY, Y,
1887                             DAG.getConstant(WidthY - 1, MVT::i32));
1888
1889  if (WidthX > WidthY)
1890    SrlY = DAG.getNode(ISD::ZERO_EXTEND, DL, TyX, SrlY);
1891  else if (WidthY > WidthX)
1892    SrlY = DAG.getNode(ISD::TRUNCATE, DL, TyX, SrlY);
1893
1894  SDValue SllY = DAG.getNode(ISD::SHL, DL, TyX, SrlY,
1895                             DAG.getConstant(WidthX - 1, MVT::i32));
1896  SDValue Or = DAG.getNode(ISD::OR, DL, TyX, SrlX, SllY);
1897  return DAG.getNode(ISD::BITCAST, DL, Op.getOperand(0).getValueType(), Or);
1898}
1899
1900SDValue
1901MipsTargetLowering::LowerFCOPYSIGN(SDValue Op, SelectionDAG &DAG) const {
1902  if (Subtarget->hasMips64())
1903    return LowerFCOPYSIGN64(Op, DAG, Subtarget->hasMips32r2());
1904
1905  return LowerFCOPYSIGN32(Op, DAG, Subtarget->hasMips32r2());
1906}
1907
1908static SDValue LowerFABS32(SDValue Op, SelectionDAG &DAG, bool HasR2) {
1909  SDValue Res, Const1 = DAG.getConstant(1, MVT::i32);
1910  DebugLoc DL = Op.getDebugLoc();
1911
1912  // If operand is of type f64, extract the upper 32-bit. Otherwise, bitcast it
1913  // to i32.
1914  SDValue X = (Op.getValueType() == MVT::f32) ?
1915    DAG.getNode(ISD::BITCAST, DL, MVT::i32, Op.getOperand(0)) :
1916    DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32, Op.getOperand(0),
1917                Const1);
1918
1919  // Clear MSB.
1920  if (HasR2)
1921    Res = DAG.getNode(MipsISD::Ins, DL, MVT::i32,
1922                      DAG.getRegister(Mips::ZERO, MVT::i32),
1923                      DAG.getConstant(31, MVT::i32), Const1, X);
1924  else {
1925    SDValue SllX = DAG.getNode(ISD::SHL, DL, MVT::i32, X, Const1);
1926    Res = DAG.getNode(ISD::SRL, DL, MVT::i32, SllX, Const1);
1927  }
1928
1929  if (Op.getValueType() == MVT::f32)
1930    return DAG.getNode(ISD::BITCAST, DL, MVT::f32, Res);
1931
1932  SDValue LowX = DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32,
1933                             Op.getOperand(0), DAG.getConstant(0, MVT::i32));
1934  return DAG.getNode(MipsISD::BuildPairF64, DL, MVT::f64, LowX, Res);
1935}
1936
1937static SDValue LowerFABS64(SDValue Op, SelectionDAG &DAG, bool HasR2) {
1938  SDValue Res, Const1 = DAG.getConstant(1, MVT::i32);
1939  DebugLoc DL = Op.getDebugLoc();
1940
1941  // Bitcast to integer node.
1942  SDValue X = DAG.getNode(ISD::BITCAST, DL, MVT::i64, Op.getOperand(0));
1943
1944  // Clear MSB.
1945  if (HasR2)
1946    Res = DAG.getNode(MipsISD::Ins, DL, MVT::i64,
1947                      DAG.getRegister(Mips::ZERO_64, MVT::i64),
1948                      DAG.getConstant(63, MVT::i32), Const1, X);
1949  else {
1950    SDValue SllX = DAG.getNode(ISD::SHL, DL, MVT::i64, X, Const1);
1951    Res = DAG.getNode(ISD::SRL, DL, MVT::i64, SllX, Const1);
1952  }
1953
1954  return DAG.getNode(ISD::BITCAST, DL, MVT::f64, Res);
1955}
1956
1957SDValue
1958MipsTargetLowering::LowerFABS(SDValue Op, SelectionDAG &DAG) const {
1959  if (Subtarget->hasMips64() && (Op.getValueType() == MVT::f64))
1960    return LowerFABS64(Op, DAG, Subtarget->hasMips32r2());
1961
1962  return LowerFABS32(Op, DAG, Subtarget->hasMips32r2());
1963}
1964
1965SDValue MipsTargetLowering::
1966LowerFRAMEADDR(SDValue Op, SelectionDAG &DAG) const {
1967  // check the depth
1968  assert((cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue() == 0) &&
1969         "Frame address can only be determined for current frame.");
1970
1971  MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo();
1972  MFI->setFrameAddressIsTaken(true);
1973  EVT VT = Op.getValueType();
1974  DebugLoc dl = Op.getDebugLoc();
1975  SDValue FrameAddr = DAG.getCopyFromReg(DAG.getEntryNode(), dl,
1976                                         IsN64 ? Mips::FP_64 : Mips::FP, VT);
1977  return FrameAddr;
1978}
1979
1980// TODO: set SType according to the desired memory barrier behavior.
1981SDValue
1982MipsTargetLowering::LowerMEMBARRIER(SDValue Op, SelectionDAG& DAG) const {
1983  unsigned SType = 0;
1984  DebugLoc dl = Op.getDebugLoc();
1985  return DAG.getNode(MipsISD::Sync, dl, MVT::Other, Op.getOperand(0),
1986                     DAG.getConstant(SType, MVT::i32));
1987}
1988
1989SDValue MipsTargetLowering::LowerATOMIC_FENCE(SDValue Op,
1990                                              SelectionDAG& DAG) const {
1991  // FIXME: Need pseudo-fence for 'singlethread' fences
1992  // FIXME: Set SType for weaker fences where supported/appropriate.
1993  unsigned SType = 0;
1994  DebugLoc dl = Op.getDebugLoc();
1995  return DAG.getNode(MipsISD::Sync, dl, MVT::Other, Op.getOperand(0),
1996                     DAG.getConstant(SType, MVT::i32));
1997}
1998
1999SDValue MipsTargetLowering::LowerShiftLeftParts(SDValue Op,
2000                                                SelectionDAG& DAG) const {
2001  DebugLoc DL = Op.getDebugLoc();
2002  SDValue Lo = Op.getOperand(0), Hi = Op.getOperand(1);
2003  SDValue Shamt = Op.getOperand(2);
2004
2005  // if shamt < 32:
2006  //  lo = (shl lo, shamt)
2007  //  hi = (or (shl hi, shamt) (srl (srl lo, 1), ~shamt))
2008  // else:
2009  //  lo = 0
2010  //  hi = (shl lo, shamt[4:0])
2011  SDValue Not = DAG.getNode(ISD::XOR, DL, MVT::i32, Shamt,
2012                            DAG.getConstant(-1, MVT::i32));
2013  SDValue ShiftRight1Lo = DAG.getNode(ISD::SRL, DL, MVT::i32, Lo,
2014                                      DAG.getConstant(1, MVT::i32));
2015  SDValue ShiftRightLo = DAG.getNode(ISD::SRL, DL, MVT::i32, ShiftRight1Lo,
2016                                     Not);
2017  SDValue ShiftLeftHi = DAG.getNode(ISD::SHL, DL, MVT::i32, Hi, Shamt);
2018  SDValue Or = DAG.getNode(ISD::OR, DL, MVT::i32, ShiftLeftHi, ShiftRightLo);
2019  SDValue ShiftLeftLo = DAG.getNode(ISD::SHL, DL, MVT::i32, Lo, Shamt);
2020  SDValue Cond = DAG.getNode(ISD::AND, DL, MVT::i32, Shamt,
2021                             DAG.getConstant(0x20, MVT::i32));
2022  Lo = DAG.getNode(ISD::SELECT, DL, MVT::i32, Cond, DAG.getConstant(0, MVT::i32),
2023                   ShiftLeftLo);
2024  Hi = DAG.getNode(ISD::SELECT, DL, MVT::i32, Cond, ShiftLeftLo, Or);
2025
2026  SDValue Ops[2] = {Lo, Hi};
2027  return DAG.getMergeValues(Ops, 2, DL);
2028}
2029
2030SDValue MipsTargetLowering::LowerShiftRightParts(SDValue Op, SelectionDAG& DAG,
2031                                                 bool IsSRA) const {
2032  DebugLoc DL = Op.getDebugLoc();
2033  SDValue Lo = Op.getOperand(0), Hi = Op.getOperand(1);
2034  SDValue Shamt = Op.getOperand(2);
2035
2036  // if shamt < 32:
2037  //  lo = (or (shl (shl hi, 1), ~shamt) (srl lo, shamt))
2038  //  if isSRA:
2039  //    hi = (sra hi, shamt)
2040  //  else:
2041  //    hi = (srl hi, shamt)
2042  // else:
2043  //  if isSRA:
2044  //   lo = (sra hi, shamt[4:0])
2045  //   hi = (sra hi, 31)
2046  //  else:
2047  //   lo = (srl hi, shamt[4:0])
2048  //   hi = 0
2049  SDValue Not = DAG.getNode(ISD::XOR, DL, MVT::i32, Shamt,
2050                            DAG.getConstant(-1, MVT::i32));
2051  SDValue ShiftLeft1Hi = DAG.getNode(ISD::SHL, DL, MVT::i32, Hi,
2052                                     DAG.getConstant(1, MVT::i32));
2053  SDValue ShiftLeftHi = DAG.getNode(ISD::SHL, DL, MVT::i32, ShiftLeft1Hi, Not);
2054  SDValue ShiftRightLo = DAG.getNode(ISD::SRL, DL, MVT::i32, Lo, Shamt);
2055  SDValue Or = DAG.getNode(ISD::OR, DL, MVT::i32, ShiftLeftHi, ShiftRightLo);
2056  SDValue ShiftRightHi = DAG.getNode(IsSRA ? ISD::SRA : ISD::SRL, DL, MVT::i32,
2057                                     Hi, Shamt);
2058  SDValue Cond = DAG.getNode(ISD::AND, DL, MVT::i32, Shamt,
2059                             DAG.getConstant(0x20, MVT::i32));
2060  SDValue Shift31 = DAG.getNode(ISD::SRA, DL, MVT::i32, Hi,
2061                                DAG.getConstant(31, MVT::i32));
2062  Lo = DAG.getNode(ISD::SELECT, DL, MVT::i32, Cond, ShiftRightHi, Or);
2063  Hi = DAG.getNode(ISD::SELECT, DL, MVT::i32, Cond,
2064                   IsSRA ? Shift31 : DAG.getConstant(0, MVT::i32),
2065                   ShiftRightHi);
2066
2067  SDValue Ops[2] = {Lo, Hi};
2068  return DAG.getMergeValues(Ops, 2, DL);
2069}
2070
2071static SDValue CreateLoadLR(unsigned Opc, SelectionDAG &DAG, LoadSDNode *LD,
2072                            SDValue Chain, SDValue Src, unsigned Offset) {
2073  SDValue BasePtr = LD->getBasePtr(), Ptr;
2074  EVT VT = LD->getValueType(0), MemVT = LD->getMemoryVT();
2075  EVT BasePtrVT = BasePtr.getValueType();
2076  DebugLoc DL = LD->getDebugLoc();
2077  SDVTList VTList = DAG.getVTList(VT, MVT::Other);
2078
2079  if (Offset)
2080    Ptr = DAG.getNode(ISD::ADD, DL, BasePtrVT, BasePtr,
2081                      DAG.getConstant(Offset, BasePtrVT));
2082  else
2083    Ptr = BasePtr;
2084
2085  SDValue Ops[] = { Chain, Ptr, Src };
2086  return DAG.getMemIntrinsicNode(Opc, DL, VTList, Ops, 3, MemVT,
2087                                 LD->getMemOperand());
2088}
2089
2090// Expand an unaligned 32 or 64-bit integer load node.
2091SDValue MipsTargetLowering::LowerLOAD(SDValue Op, SelectionDAG &DAG) const {
2092  LoadSDNode *LD = cast<LoadSDNode>(Op);
2093  EVT MemVT = LD->getMemoryVT();
2094
2095  // Return if load is aligned or if MemVT is neither i32 nor i64.
2096  if ((LD->getAlignment() >= MemVT.getSizeInBits() / 8) ||
2097      ((MemVT != MVT::i32) && (MemVT != MVT::i64)))
2098    return SDValue();
2099
2100  bool IsLittle = Subtarget->isLittle();
2101  EVT VT = Op.getValueType();
2102  ISD::LoadExtType ExtType = LD->getExtensionType();
2103  SDValue Chain = LD->getChain(), Undef = DAG.getUNDEF(VT);
2104
2105  assert((VT == MVT::i32) || (VT == MVT::i64));
2106
2107  // Expand
2108  //  (set dst, (i64 (load baseptr)))
2109  // to
2110  //  (set tmp, (ldl (add baseptr, 7), undef))
2111  //  (set dst, (ldr baseptr, tmp))
2112  if ((VT == MVT::i64) && (ExtType == ISD::NON_EXTLOAD)) {
2113    SDValue LDL = CreateLoadLR(MipsISD::LDL, DAG, LD, Chain, Undef,
2114                               IsLittle ? 7 : 0);
2115    return CreateLoadLR(MipsISD::LDR, DAG, LD, LDL.getValue(1), LDL,
2116                        IsLittle ? 0 : 7);
2117  }
2118
2119  SDValue LWL = CreateLoadLR(MipsISD::LWL, DAG, LD, Chain, Undef,
2120                             IsLittle ? 3 : 0);
2121  SDValue LWR = CreateLoadLR(MipsISD::LWR, DAG, LD, LWL.getValue(1), LWL,
2122                             IsLittle ? 0 : 3);
2123
2124  // Expand
2125  //  (set dst, (i32 (load baseptr))) or
2126  //  (set dst, (i64 (sextload baseptr))) or
2127  //  (set dst, (i64 (extload baseptr)))
2128  // to
2129  //  (set tmp, (lwl (add baseptr, 3), undef))
2130  //  (set dst, (lwr baseptr, tmp))
2131  if ((VT == MVT::i32) || (ExtType == ISD::SEXTLOAD) ||
2132      (ExtType == ISD::EXTLOAD))
2133    return LWR;
2134
2135  assert((VT == MVT::i64) && (ExtType == ISD::ZEXTLOAD));
2136
2137  // Expand
2138  //  (set dst, (i64 (zextload baseptr)))
2139  // to
2140  //  (set tmp0, (lwl (add baseptr, 3), undef))
2141  //  (set tmp1, (lwr baseptr, tmp0))
2142  //  (set tmp2, (shl tmp1, 32))
2143  //  (set dst, (srl tmp2, 32))
2144  DebugLoc DL = LD->getDebugLoc();
2145  SDValue Const32 = DAG.getConstant(32, MVT::i32);
2146  SDValue SLL = DAG.getNode(ISD::SHL, DL, MVT::i64, LWR, Const32);
2147  SDValue Ops[] = { SLL, LWR.getValue(1) };
2148  return DAG.getMergeValues(Ops, 2, DL);
2149}
2150
2151static SDValue CreateStoreLR(unsigned Opc, SelectionDAG &DAG, StoreSDNode *SD,
2152                             SDValue Chain, unsigned Offset) {
2153  SDValue BasePtr = SD->getBasePtr(), Ptr, Value = SD->getValue();
2154  EVT MemVT = SD->getMemoryVT();
2155  EVT BasePtrVT = BasePtr.getValueType();
2156  DebugLoc DL = SD->getDebugLoc();
2157  SDVTList VTList = DAG.getVTList(MVT::Other);
2158
2159  if (Offset)
2160    Ptr = DAG.getNode(ISD::ADD, DL, BasePtrVT, BasePtr,
2161                      DAG.getConstant(Offset, BasePtrVT));
2162  else
2163    Ptr = BasePtr;
2164
2165  SDValue Ops[] = { Chain, Value, Ptr };
2166  return DAG.getMemIntrinsicNode(Opc, DL, VTList, Ops, 3, MemVT,
2167                                 SD->getMemOperand());
2168}
2169
2170// Expand an unaligned 32 or 64-bit integer store node.
2171SDValue MipsTargetLowering::LowerSTORE(SDValue Op, SelectionDAG &DAG) const {
2172  StoreSDNode *SD = cast<StoreSDNode>(Op);
2173  EVT MemVT = SD->getMemoryVT();
2174
2175  // Return if store is aligned or if MemVT is neither i32 nor i64.
2176  if ((SD->getAlignment() >= MemVT.getSizeInBits() / 8) ||
2177      ((MemVT != MVT::i32) && (MemVT != MVT::i64)))
2178    return SDValue();
2179
2180  bool IsLittle = Subtarget->isLittle();
2181  SDValue Value = SD->getValue(), Chain = SD->getChain();
2182  EVT VT = Value.getValueType();
2183
2184  // Expand
2185  //  (store val, baseptr) or
2186  //  (truncstore val, baseptr)
2187  // to
2188  //  (swl val, (add baseptr, 3))
2189  //  (swr val, baseptr)
2190  if ((VT == MVT::i32) || SD->isTruncatingStore()) {
2191    SDValue SWL = CreateStoreLR(MipsISD::SWL, DAG, SD, Chain,
2192                                IsLittle ? 3 : 0);
2193    return CreateStoreLR(MipsISD::SWR, DAG, SD, SWL, IsLittle ? 0 : 3);
2194  }
2195
2196  assert(VT == MVT::i64);
2197
2198  // Expand
2199  //  (store val, baseptr)
2200  // to
2201  //  (sdl val, (add baseptr, 7))
2202  //  (sdr val, baseptr)
2203  SDValue SDL = CreateStoreLR(MipsISD::SDL, DAG, SD, Chain, IsLittle ? 7 : 0);
2204  return CreateStoreLR(MipsISD::SDR, DAG, SD, SDL, IsLittle ? 0 : 7);
2205}
2206
2207//===----------------------------------------------------------------------===//
2208//                      Calling Convention Implementation
2209//===----------------------------------------------------------------------===//
2210
2211//===----------------------------------------------------------------------===//
2212// TODO: Implement a generic logic using tblgen that can support this.
2213// Mips O32 ABI rules:
2214// ---
2215// i32 - Passed in A0, A1, A2, A3 and stack
2216// f32 - Only passed in f32 registers if no int reg has been used yet to hold
2217//       an argument. Otherwise, passed in A1, A2, A3 and stack.
2218// f64 - Only passed in two aliased f32 registers if no int reg has been used
2219//       yet to hold an argument. Otherwise, use A2, A3 and stack. If A1 is
2220//       not used, it must be shadowed. If only A3 is avaiable, shadow it and
2221//       go to stack.
2222//
2223//  For vararg functions, all arguments are passed in A0, A1, A2, A3 and stack.
2224//===----------------------------------------------------------------------===//
2225
2226static bool CC_MipsO32(unsigned ValNo, MVT ValVT,
2227                       MVT LocVT, CCValAssign::LocInfo LocInfo,
2228                       ISD::ArgFlagsTy ArgFlags, CCState &State) {
2229
2230  static const unsigned IntRegsSize=4, FloatRegsSize=2;
2231
2232  static const uint16_t IntRegs[] = {
2233      Mips::A0, Mips::A1, Mips::A2, Mips::A3
2234  };
2235  static const uint16_t F32Regs[] = {
2236      Mips::F12, Mips::F14
2237  };
2238  static const uint16_t F64Regs[] = {
2239      Mips::D6, Mips::D7
2240  };
2241
2242  // ByVal Args
2243  if (ArgFlags.isByVal()) {
2244    State.HandleByVal(ValNo, ValVT, LocVT, LocInfo,
2245                      1 /*MinSize*/, 4 /*MinAlign*/, ArgFlags);
2246    unsigned NextReg = (State.getNextStackOffset() + 3) / 4;
2247    for (unsigned r = State.getFirstUnallocated(IntRegs, IntRegsSize);
2248         r < std::min(IntRegsSize, NextReg); ++r)
2249      State.AllocateReg(IntRegs[r]);
2250    return false;
2251  }
2252
2253  // Promote i8 and i16
2254  if (LocVT == MVT::i8 || LocVT == MVT::i16) {
2255    LocVT = MVT::i32;
2256    if (ArgFlags.isSExt())
2257      LocInfo = CCValAssign::SExt;
2258    else if (ArgFlags.isZExt())
2259      LocInfo = CCValAssign::ZExt;
2260    else
2261      LocInfo = CCValAssign::AExt;
2262  }
2263
2264  unsigned Reg;
2265
2266  // f32 and f64 are allocated in A0, A1, A2, A3 when either of the following
2267  // is true: function is vararg, argument is 3rd or higher, there is previous
2268  // argument which is not f32 or f64.
2269  bool AllocateFloatsInIntReg = State.isVarArg() || ValNo > 1
2270      || State.getFirstUnallocated(F32Regs, FloatRegsSize) != ValNo;
2271  unsigned OrigAlign = ArgFlags.getOrigAlign();
2272  bool isI64 = (ValVT == MVT::i32 && OrigAlign == 8);
2273
2274  if (ValVT == MVT::i32 || (ValVT == MVT::f32 && AllocateFloatsInIntReg)) {
2275    Reg = State.AllocateReg(IntRegs, IntRegsSize);
2276    // If this is the first part of an i64 arg,
2277    // the allocated register must be either A0 or A2.
2278    if (isI64 && (Reg == Mips::A1 || Reg == Mips::A3))
2279      Reg = State.AllocateReg(IntRegs, IntRegsSize);
2280    LocVT = MVT::i32;
2281  } else if (ValVT == MVT::f64 && AllocateFloatsInIntReg) {
2282    // Allocate int register and shadow next int register. If first
2283    // available register is Mips::A1 or Mips::A3, shadow it too.
2284    Reg = State.AllocateReg(IntRegs, IntRegsSize);
2285    if (Reg == Mips::A1 || Reg == Mips::A3)
2286      Reg = State.AllocateReg(IntRegs, IntRegsSize);
2287    State.AllocateReg(IntRegs, IntRegsSize);
2288    LocVT = MVT::i32;
2289  } else if (ValVT.isFloatingPoint() && !AllocateFloatsInIntReg) {
2290    // we are guaranteed to find an available float register
2291    if (ValVT == MVT::f32) {
2292      Reg = State.AllocateReg(F32Regs, FloatRegsSize);
2293      // Shadow int register
2294      State.AllocateReg(IntRegs, IntRegsSize);
2295    } else {
2296      Reg = State.AllocateReg(F64Regs, FloatRegsSize);
2297      // Shadow int registers
2298      unsigned Reg2 = State.AllocateReg(IntRegs, IntRegsSize);
2299      if (Reg2 == Mips::A1 || Reg2 == Mips::A3)
2300        State.AllocateReg(IntRegs, IntRegsSize);
2301      State.AllocateReg(IntRegs, IntRegsSize);
2302    }
2303  } else
2304    llvm_unreachable("Cannot handle this ValVT.");
2305
2306  unsigned SizeInBytes = ValVT.getSizeInBits() >> 3;
2307  unsigned Offset = State.AllocateStack(SizeInBytes, OrigAlign);
2308
2309  if (!Reg)
2310    State.addLoc(CCValAssign::getMem(ValNo, ValVT, Offset, LocVT, LocInfo));
2311  else
2312    State.addLoc(CCValAssign::getReg(ValNo, ValVT, Reg, LocVT, LocInfo));
2313
2314  return false; // CC must always match
2315}
2316
2317static const uint16_t Mips64IntRegs[8] =
2318  {Mips::A0_64, Mips::A1_64, Mips::A2_64, Mips::A3_64,
2319   Mips::T0_64, Mips::T1_64, Mips::T2_64, Mips::T3_64};
2320static const uint16_t Mips64DPRegs[8] =
2321  {Mips::D12_64, Mips::D13_64, Mips::D14_64, Mips::D15_64,
2322   Mips::D16_64, Mips::D17_64, Mips::D18_64, Mips::D19_64};
2323
2324static bool CC_Mips64Byval(unsigned ValNo, MVT ValVT, MVT LocVT,
2325                           CCValAssign::LocInfo LocInfo,
2326                           ISD::ArgFlagsTy ArgFlags, CCState &State) {
2327  unsigned Align = std::max(ArgFlags.getByValAlign(), (unsigned)8);
2328  unsigned Size  = (ArgFlags.getByValSize() + 7) / 8 * 8;
2329  unsigned FirstIdx = State.getFirstUnallocated(Mips64IntRegs, 8);
2330
2331  assert(Align <= 16 && "Cannot handle alignments larger than 16.");
2332
2333  // If byval is 16-byte aligned, the first arg register must be even.
2334  if ((Align == 16) && (FirstIdx % 2)) {
2335    State.AllocateReg(Mips64IntRegs[FirstIdx], Mips64DPRegs[FirstIdx]);
2336    ++FirstIdx;
2337  }
2338
2339  // Mark the registers allocated.
2340  for (unsigned I = FirstIdx; Size && (I < 8); Size -= 8, ++I)
2341    State.AllocateReg(Mips64IntRegs[I], Mips64DPRegs[I]);
2342
2343  // Allocate space on caller's stack.
2344  unsigned Offset = State.AllocateStack(Size, Align);
2345
2346  if (FirstIdx < 8)
2347    State.addLoc(CCValAssign::getReg(ValNo, ValVT, Mips64IntRegs[FirstIdx],
2348                                     LocVT, LocInfo));
2349  else
2350    State.addLoc(CCValAssign::getMem(ValNo, ValVT, Offset, LocVT, LocInfo));
2351
2352  return true;
2353}
2354
2355#include "MipsGenCallingConv.inc"
2356
2357static void
2358AnalyzeMips64CallOperands(CCState &CCInfo,
2359                          const SmallVectorImpl<ISD::OutputArg> &Outs) {
2360  unsigned NumOps = Outs.size();
2361  for (unsigned i = 0; i != NumOps; ++i) {
2362    MVT ArgVT = Outs[i].VT;
2363    ISD::ArgFlagsTy ArgFlags = Outs[i].Flags;
2364    bool R;
2365
2366    if (Outs[i].IsFixed)
2367      R = CC_MipsN(i, ArgVT, ArgVT, CCValAssign::Full, ArgFlags, CCInfo);
2368    else
2369      R = CC_MipsN_VarArg(i, ArgVT, ArgVT, CCValAssign::Full, ArgFlags, CCInfo);
2370
2371    if (R) {
2372#ifndef NDEBUG
2373      dbgs() << "Call operand #" << i << " has unhandled type "
2374             << EVT(ArgVT).getEVTString();
2375#endif
2376      llvm_unreachable(0);
2377    }
2378  }
2379}
2380
2381//===----------------------------------------------------------------------===//
2382//                  Call Calling Convention Implementation
2383//===----------------------------------------------------------------------===//
2384
2385static const unsigned O32IntRegsSize = 4;
2386
2387static const uint16_t O32IntRegs[] = {
2388  Mips::A0, Mips::A1, Mips::A2, Mips::A3
2389};
2390
2391// Return next O32 integer argument register.
2392static unsigned getNextIntArgReg(unsigned Reg) {
2393  assert((Reg == Mips::A0) || (Reg == Mips::A2));
2394  return (Reg == Mips::A0) ? Mips::A1 : Mips::A3;
2395}
2396
2397// Write ByVal Arg to arg registers and stack.
2398static void
2399WriteByValArg(SDValue& ByValChain, SDValue Chain, DebugLoc dl,
2400              SmallVector<std::pair<unsigned, SDValue>, 16>& RegsToPass,
2401              SmallVector<SDValue, 8>& MemOpChains, int& LastFI,
2402              MachineFrameInfo *MFI, SelectionDAG &DAG, SDValue Arg,
2403              const CCValAssign &VA, const ISD::ArgFlagsTy& Flags,
2404              MVT PtrType, bool isLittle) {
2405  unsigned LocMemOffset = VA.getLocMemOffset();
2406  unsigned Offset = 0;
2407  uint32_t RemainingSize = Flags.getByValSize();
2408  unsigned ByValAlign = Flags.getByValAlign();
2409
2410  // Copy the first 4 words of byval arg to registers A0 - A3.
2411  // FIXME: Use a stricter alignment if it enables better optimization in passes
2412  //        run later.
2413  for (; RemainingSize >= 4 && LocMemOffset < 4 * 4;
2414       Offset += 4, RemainingSize -= 4, LocMemOffset += 4) {
2415    SDValue LoadPtr = DAG.getNode(ISD::ADD, dl, MVT::i32, Arg,
2416                                  DAG.getConstant(Offset, MVT::i32));
2417    SDValue LoadVal = DAG.getLoad(MVT::i32, dl, Chain, LoadPtr,
2418                                  MachinePointerInfo(), false, false, false,
2419                                  std::min(ByValAlign, (unsigned )4));
2420    MemOpChains.push_back(LoadVal.getValue(1));
2421    unsigned DstReg = O32IntRegs[LocMemOffset / 4];
2422    RegsToPass.push_back(std::make_pair(DstReg, LoadVal));
2423  }
2424
2425  if (RemainingSize == 0)
2426    return;
2427
2428  // If there still is a register available for argument passing, write the
2429  // remaining part of the structure to it using subword loads and shifts.
2430  if (LocMemOffset < 4 * 4) {
2431    assert(RemainingSize <= 3 && RemainingSize >= 1 &&
2432           "There must be one to three bytes remaining.");
2433    unsigned LoadSize = (RemainingSize == 3 ? 2 : RemainingSize);
2434    SDValue LoadPtr = DAG.getNode(ISD::ADD, dl, MVT::i32, Arg,
2435                                  DAG.getConstant(Offset, MVT::i32));
2436    unsigned Alignment = std::min(ByValAlign, (unsigned )4);
2437    SDValue LoadVal = DAG.getExtLoad(ISD::ZEXTLOAD, dl, MVT::i32, Chain,
2438                                     LoadPtr, MachinePointerInfo(),
2439                                     MVT::getIntegerVT(LoadSize * 8), false,
2440                                     false, Alignment);
2441    MemOpChains.push_back(LoadVal.getValue(1));
2442
2443    // If target is big endian, shift it to the most significant half-word or
2444    // byte.
2445    if (!isLittle)
2446      LoadVal = DAG.getNode(ISD::SHL, dl, MVT::i32, LoadVal,
2447                            DAG.getConstant(32 - LoadSize * 8, MVT::i32));
2448
2449    Offset += LoadSize;
2450    RemainingSize -= LoadSize;
2451
2452    // Read second subword if necessary.
2453    if (RemainingSize != 0)  {
2454      assert(RemainingSize == 1 && "There must be one byte remaining.");
2455      LoadPtr = DAG.getNode(ISD::ADD, dl, MVT::i32, Arg,
2456                            DAG.getConstant(Offset, MVT::i32));
2457      unsigned Alignment = std::min(ByValAlign, (unsigned )2);
2458      SDValue Subword = DAG.getExtLoad(ISD::ZEXTLOAD, dl, MVT::i32, Chain,
2459                                       LoadPtr, MachinePointerInfo(),
2460                                       MVT::i8, false, false, Alignment);
2461      MemOpChains.push_back(Subword.getValue(1));
2462      // Insert the loaded byte to LoadVal.
2463      // FIXME: Use INS if supported by target.
2464      unsigned ShiftAmt = isLittle ? 16 : 8;
2465      SDValue Shift = DAG.getNode(ISD::SHL, dl, MVT::i32, Subword,
2466                                  DAG.getConstant(ShiftAmt, MVT::i32));
2467      LoadVal = DAG.getNode(ISD::OR, dl, MVT::i32, LoadVal, Shift);
2468    }
2469
2470    unsigned DstReg = O32IntRegs[LocMemOffset / 4];
2471    RegsToPass.push_back(std::make_pair(DstReg, LoadVal));
2472    return;
2473  }
2474
2475  // Create a fixed object on stack at offset LocMemOffset and copy
2476  // remaining part of byval arg to it using memcpy.
2477  SDValue Src = DAG.getNode(ISD::ADD, dl, MVT::i32, Arg,
2478                            DAG.getConstant(Offset, MVT::i32));
2479  LastFI = MFI->CreateFixedObject(RemainingSize, LocMemOffset, true);
2480  SDValue Dst = DAG.getFrameIndex(LastFI, PtrType);
2481  ByValChain = DAG.getMemcpy(ByValChain, dl, Dst, Src,
2482                             DAG.getConstant(RemainingSize, MVT::i32),
2483                             std::min(ByValAlign, (unsigned)4),
2484                             /*isVolatile=*/false, /*AlwaysInline=*/false,
2485                             MachinePointerInfo(0), MachinePointerInfo(0));
2486}
2487
2488// Copy Mips64 byVal arg to registers and stack.
2489void static
2490PassByValArg64(SDValue& ByValChain, SDValue Chain, DebugLoc dl,
2491               SmallVector<std::pair<unsigned, SDValue>, 16>& RegsToPass,
2492               SmallVector<SDValue, 8>& MemOpChains, int& LastFI,
2493               MachineFrameInfo *MFI, SelectionDAG &DAG, SDValue Arg,
2494               const CCValAssign &VA, const ISD::ArgFlagsTy& Flags,
2495               EVT PtrTy, bool isLittle) {
2496  unsigned ByValSize = Flags.getByValSize();
2497  unsigned Alignment = std::min(Flags.getByValAlign(), (unsigned)8);
2498  bool IsRegLoc = VA.isRegLoc();
2499  unsigned Offset = 0; // Offset in # of bytes from the beginning of struct.
2500  unsigned LocMemOffset = 0;
2501  unsigned MemCpySize = ByValSize;
2502
2503  if (!IsRegLoc)
2504    LocMemOffset = VA.getLocMemOffset();
2505  else {
2506    const uint16_t *Reg = std::find(Mips64IntRegs, Mips64IntRegs + 8,
2507                                    VA.getLocReg());
2508    const uint16_t *RegEnd = Mips64IntRegs + 8;
2509
2510    // Copy double words to registers.
2511    for (; (Reg != RegEnd) && (ByValSize >= Offset + 8); ++Reg, Offset += 8) {
2512      SDValue LoadPtr = DAG.getNode(ISD::ADD, dl, PtrTy, Arg,
2513                                    DAG.getConstant(Offset, PtrTy));
2514      SDValue LoadVal = DAG.getLoad(MVT::i64, dl, Chain, LoadPtr,
2515                                    MachinePointerInfo(), false, false, false,
2516                                    Alignment);
2517      MemOpChains.push_back(LoadVal.getValue(1));
2518      RegsToPass.push_back(std::make_pair(*Reg, LoadVal));
2519    }
2520
2521    // Return if the struct has been fully copied.
2522    if (!(MemCpySize = ByValSize - Offset))
2523      return;
2524
2525    // If there is an argument register available, copy the remainder of the
2526    // byval argument with sub-doubleword loads and shifts.
2527    if (Reg != RegEnd) {
2528      assert((ByValSize < Offset + 8) &&
2529             "Size of the remainder should be smaller than 8-byte.");
2530      SDValue Val;
2531      for (unsigned LoadSize = 4; Offset < ByValSize; LoadSize /= 2) {
2532        unsigned RemSize = ByValSize - Offset;
2533
2534        if (RemSize < LoadSize)
2535          continue;
2536
2537        SDValue LoadPtr = DAG.getNode(ISD::ADD, dl, PtrTy, Arg,
2538                                      DAG.getConstant(Offset, PtrTy));
2539        SDValue LoadVal =
2540          DAG.getExtLoad(ISD::ZEXTLOAD, dl, MVT::i64, Chain, LoadPtr,
2541                         MachinePointerInfo(), MVT::getIntegerVT(LoadSize * 8),
2542                         false, false, Alignment);
2543        MemOpChains.push_back(LoadVal.getValue(1));
2544
2545        // Offset in number of bits from double word boundary.
2546        unsigned OffsetDW = (Offset % 8) * 8;
2547        unsigned Shamt = isLittle ? OffsetDW : 64 - (OffsetDW + LoadSize * 8);
2548        SDValue Shift = DAG.getNode(ISD::SHL, dl, MVT::i64, LoadVal,
2549                                    DAG.getConstant(Shamt, MVT::i32));
2550
2551        Val = Val.getNode() ? DAG.getNode(ISD::OR, dl, MVT::i64, Val, Shift) :
2552                              Shift;
2553        Offset += LoadSize;
2554        Alignment = std::min(Alignment, LoadSize);
2555      }
2556
2557      RegsToPass.push_back(std::make_pair(*Reg, Val));
2558      return;
2559    }
2560  }
2561
2562  assert(MemCpySize && "MemCpySize must not be zero.");
2563
2564  // Create a fixed object on stack at offset LocMemOffset and copy
2565  // remainder of byval arg to it with memcpy.
2566  SDValue Src = DAG.getNode(ISD::ADD, dl, PtrTy, Arg,
2567                            DAG.getConstant(Offset, PtrTy));
2568  LastFI = MFI->CreateFixedObject(MemCpySize, LocMemOffset, true);
2569  SDValue Dst = DAG.getFrameIndex(LastFI, PtrTy);
2570  ByValChain = DAG.getMemcpy(ByValChain, dl, Dst, Src,
2571                             DAG.getConstant(MemCpySize, PtrTy), Alignment,
2572                             /*isVolatile=*/false, /*AlwaysInline=*/false,
2573                             MachinePointerInfo(0), MachinePointerInfo(0));
2574}
2575
2576/// LowerCall - functions arguments are copied from virtual regs to
2577/// (physical regs)/(stack frame), CALLSEQ_START and CALLSEQ_END are emitted.
2578/// TODO: isTailCall.
2579SDValue
2580MipsTargetLowering::LowerCall(TargetLowering::CallLoweringInfo &CLI,
2581                              SmallVectorImpl<SDValue> &InVals) const {
2582  SelectionDAG &DAG                     = CLI.DAG;
2583  DebugLoc &dl                          = CLI.DL;
2584  SmallVector<ISD::OutputArg, 32> &Outs = CLI.Outs;
2585  SmallVector<SDValue, 32> &OutVals     = CLI.OutVals;
2586  SmallVector<ISD::InputArg, 32> &Ins   = CLI.Ins;
2587  SDValue InChain                       = CLI.Chain;
2588  SDValue Callee                        = CLI.Callee;
2589  bool &isTailCall                      = CLI.IsTailCall;
2590  CallingConv::ID CallConv              = CLI.CallConv;
2591  bool isVarArg                         = CLI.IsVarArg;
2592
2593  // MIPs target does not yet support tail call optimization.
2594  isTailCall = false;
2595
2596  MachineFunction &MF = DAG.getMachineFunction();
2597  MachineFrameInfo *MFI = MF.getFrameInfo();
2598  const TargetFrameLowering *TFL = MF.getTarget().getFrameLowering();
2599  bool IsPIC = getTargetMachine().getRelocationModel() == Reloc::PIC_;
2600  MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
2601
2602  // Analyze operands of the call, assigning locations to each operand.
2603  SmallVector<CCValAssign, 16> ArgLocs;
2604  CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(),
2605                 getTargetMachine(), ArgLocs, *DAG.getContext());
2606
2607  if (IsO32)
2608    CCInfo.AnalyzeCallOperands(Outs, CC_MipsO32);
2609  else if (HasMips64)
2610    AnalyzeMips64CallOperands(CCInfo, Outs);
2611  else
2612    CCInfo.AnalyzeCallOperands(Outs, CC_Mips);
2613
2614  // Get a count of how many bytes are to be pushed on the stack.
2615  unsigned NextStackOffset = CCInfo.getNextStackOffset();
2616
2617  // Chain is the output chain of the last Load/Store or CopyToReg node.
2618  // ByValChain is the output chain of the last Memcpy node created for copying
2619  // byval arguments to the stack.
2620  SDValue Chain, CallSeqStart, ByValChain;
2621  SDValue NextStackOffsetVal = DAG.getIntPtrConstant(NextStackOffset, true);
2622  Chain = CallSeqStart = DAG.getCALLSEQ_START(InChain, NextStackOffsetVal);
2623  ByValChain = InChain;
2624
2625  // Get the frame index of the stack frame object that points to the location
2626  // of dynamically allocated area on the stack.
2627  int DynAllocFI = MipsFI->getDynAllocFI();
2628
2629  // Update size of the maximum argument space.
2630  // For O32, a minimum of four words (16 bytes) of argument space is
2631  // allocated.
2632  if (IsO32)
2633    NextStackOffset = std::max(NextStackOffset, (unsigned)16);
2634
2635  unsigned MaxCallFrameSize = MipsFI->getMaxCallFrameSize();
2636
2637  if (MaxCallFrameSize < NextStackOffset) {
2638    MipsFI->setMaxCallFrameSize(NextStackOffset);
2639
2640    // Set the offsets relative to $sp of the $gp restore slot and dynamically
2641    // allocated stack space. These offsets must be aligned to a boundary
2642    // determined by the stack alignment of the ABI.
2643    unsigned StackAlignment = TFL->getStackAlignment();
2644    NextStackOffset = (NextStackOffset + StackAlignment - 1) /
2645                      StackAlignment * StackAlignment;
2646
2647    MFI->setObjectOffset(DynAllocFI, NextStackOffset);
2648  }
2649
2650  // With EABI is it possible to have 16 args on registers.
2651  SmallVector<std::pair<unsigned, SDValue>, 16> RegsToPass;
2652  SmallVector<SDValue, 8> MemOpChains;
2653
2654  int FirstFI = -MFI->getNumFixedObjects() - 1, LastFI = 0;
2655
2656  // Walk the register/memloc assignments, inserting copies/loads.
2657  for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
2658    SDValue Arg = OutVals[i];
2659    CCValAssign &VA = ArgLocs[i];
2660    MVT ValVT = VA.getValVT(), LocVT = VA.getLocVT();
2661    ISD::ArgFlagsTy Flags = Outs[i].Flags;
2662
2663    // ByVal Arg.
2664    if (Flags.isByVal()) {
2665      assert(Flags.getByValSize() &&
2666             "ByVal args of size 0 should have been ignored by front-end.");
2667      if (IsO32)
2668        WriteByValArg(ByValChain, Chain, dl, RegsToPass, MemOpChains, LastFI,
2669                      MFI, DAG, Arg, VA, Flags, getPointerTy(),
2670                      Subtarget->isLittle());
2671      else
2672        PassByValArg64(ByValChain, Chain, dl, RegsToPass, MemOpChains, LastFI,
2673                       MFI, DAG, Arg, VA, Flags, getPointerTy(),
2674                       Subtarget->isLittle());
2675      continue;
2676    }
2677
2678    // Promote the value if needed.
2679    switch (VA.getLocInfo()) {
2680    default: llvm_unreachable("Unknown loc info!");
2681    case CCValAssign::Full:
2682      if (VA.isRegLoc()) {
2683        if ((ValVT == MVT::f32 && LocVT == MVT::i32) ||
2684            (ValVT == MVT::f64 && LocVT == MVT::i64))
2685          Arg = DAG.getNode(ISD::BITCAST, dl, LocVT, Arg);
2686        else if (ValVT == MVT::f64 && LocVT == MVT::i32) {
2687          SDValue Lo = DAG.getNode(MipsISD::ExtractElementF64, dl, MVT::i32,
2688                                   Arg, DAG.getConstant(0, MVT::i32));
2689          SDValue Hi = DAG.getNode(MipsISD::ExtractElementF64, dl, MVT::i32,
2690                                   Arg, DAG.getConstant(1, MVT::i32));
2691          if (!Subtarget->isLittle())
2692            std::swap(Lo, Hi);
2693          unsigned LocRegLo = VA.getLocReg();
2694          unsigned LocRegHigh = getNextIntArgReg(LocRegLo);
2695          RegsToPass.push_back(std::make_pair(LocRegLo, Lo));
2696          RegsToPass.push_back(std::make_pair(LocRegHigh, Hi));
2697          continue;
2698        }
2699      }
2700      break;
2701    case CCValAssign::SExt:
2702      Arg = DAG.getNode(ISD::SIGN_EXTEND, dl, LocVT, Arg);
2703      break;
2704    case CCValAssign::ZExt:
2705      Arg = DAG.getNode(ISD::ZERO_EXTEND, dl, LocVT, Arg);
2706      break;
2707    case CCValAssign::AExt:
2708      Arg = DAG.getNode(ISD::ANY_EXTEND, dl, LocVT, Arg);
2709      break;
2710    }
2711
2712    // Arguments that can be passed on register must be kept at
2713    // RegsToPass vector
2714    if (VA.isRegLoc()) {
2715      RegsToPass.push_back(std::make_pair(VA.getLocReg(), Arg));
2716      continue;
2717    }
2718
2719    // Register can't get to this point...
2720    assert(VA.isMemLoc());
2721
2722    // Create the frame index object for this incoming parameter
2723    LastFI = MFI->CreateFixedObject(ValVT.getSizeInBits()/8,
2724                                    VA.getLocMemOffset(), true);
2725    SDValue PtrOff = DAG.getFrameIndex(LastFI, getPointerTy());
2726
2727    // emit ISD::STORE whichs stores the
2728    // parameter value to a stack Location
2729    MemOpChains.push_back(DAG.getStore(Chain, dl, Arg, PtrOff,
2730                                       MachinePointerInfo(), false, false, 0));
2731  }
2732
2733  // Extend range of indices of frame objects for outgoing arguments that were
2734  // created during this function call. Skip this step if no such objects were
2735  // created.
2736  if (LastFI)
2737    MipsFI->extendOutArgFIRange(FirstFI, LastFI);
2738
2739  // If a memcpy has been created to copy a byval arg to a stack, replace the
2740  // chain input of CallSeqStart with ByValChain.
2741  if (InChain != ByValChain)
2742    DAG.UpdateNodeOperands(CallSeqStart.getNode(), ByValChain,
2743                           NextStackOffsetVal);
2744
2745  // Transform all store nodes into one single node because all store
2746  // nodes are independent of each other.
2747  if (!MemOpChains.empty())
2748    Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
2749                        &MemOpChains[0], MemOpChains.size());
2750
2751  // If the callee is a GlobalAddress/ExternalSymbol node (quite common, every
2752  // direct call is) turn it into a TargetGlobalAddress/TargetExternalSymbol
2753  // node so that legalize doesn't hack it.
2754  unsigned char OpFlag;
2755  bool IsPICCall = (IsN64 || IsPIC); // true if calls are translated to jalr $25
2756  bool GlobalOrExternal = false;
2757  SDValue CalleeLo;
2758
2759  if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee)) {
2760    if (IsPICCall && G->getGlobal()->hasInternalLinkage()) {
2761      OpFlag = IsO32 ? MipsII::MO_GOT : MipsII::MO_GOT_PAGE;
2762      unsigned char LoFlag = IsO32 ? MipsII::MO_ABS_LO : MipsII::MO_GOT_OFST;
2763      Callee = DAG.getTargetGlobalAddress(G->getGlobal(), dl, getPointerTy(), 0,
2764                                          OpFlag);
2765      CalleeLo = DAG.getTargetGlobalAddress(G->getGlobal(), dl, getPointerTy(),
2766                                            0, LoFlag);
2767    } else {
2768      OpFlag = IsPICCall ? MipsII::MO_GOT_CALL : MipsII::MO_NO_FLAG;
2769      Callee = DAG.getTargetGlobalAddress(G->getGlobal(), dl,
2770                                          getPointerTy(), 0, OpFlag);
2771    }
2772
2773    GlobalOrExternal = true;
2774  }
2775  else if (ExternalSymbolSDNode *S = dyn_cast<ExternalSymbolSDNode>(Callee)) {
2776    if (IsN64 || (!IsO32 && IsPIC))
2777      OpFlag = MipsII::MO_GOT_DISP;
2778    else if (!IsPIC) // !N64 && static
2779      OpFlag = MipsII::MO_NO_FLAG;
2780    else // O32 & PIC
2781      OpFlag = MipsII::MO_GOT_CALL;
2782    Callee = DAG.getTargetExternalSymbol(S->getSymbol(), getPointerTy(),
2783                                         OpFlag);
2784    GlobalOrExternal = true;
2785  }
2786
2787  SDValue InFlag;
2788
2789  // Create nodes that load address of callee and copy it to T9
2790  if (IsPICCall) {
2791    if (GlobalOrExternal) {
2792      // Load callee address
2793      Callee = DAG.getNode(MipsISD::Wrapper, dl, getPointerTy(),
2794                           GetGlobalReg(DAG, getPointerTy()), Callee);
2795      SDValue LoadValue = DAG.getLoad(getPointerTy(), dl, DAG.getEntryNode(),
2796                                      Callee, MachinePointerInfo::getGOT(),
2797                                      false, false, false, 0);
2798
2799      // Use GOT+LO if callee has internal linkage.
2800      if (CalleeLo.getNode()) {
2801        SDValue Lo = DAG.getNode(MipsISD::Lo, dl, getPointerTy(), CalleeLo);
2802        Callee = DAG.getNode(ISD::ADD, dl, getPointerTy(), LoadValue, Lo);
2803      } else
2804        Callee = LoadValue;
2805    }
2806  }
2807
2808  // T9 should contain the address of the callee function if
2809  // -reloction-model=pic or it is an indirect call.
2810  if (IsPICCall || !GlobalOrExternal) {
2811    // copy to T9
2812    unsigned T9Reg = IsN64 ? Mips::T9_64 : Mips::T9;
2813    Chain = DAG.getCopyToReg(Chain, dl, T9Reg, Callee, SDValue(0, 0));
2814    InFlag = Chain.getValue(1);
2815    Callee = DAG.getRegister(T9Reg, getPointerTy());
2816  }
2817
2818  // Insert node "GP copy globalreg" before call to function.
2819  // Lazy-binding stubs require GP to point to the GOT.
2820  if (IsPICCall) {
2821    unsigned GPReg = IsN64 ? Mips::GP_64 : Mips::GP;
2822    EVT Ty = IsN64 ? MVT::i64 : MVT::i32;
2823    RegsToPass.push_back(std::make_pair(GPReg, GetGlobalReg(DAG, Ty)));
2824  }
2825
2826  // Build a sequence of copy-to-reg nodes chained together with token
2827  // chain and flag operands which copy the outgoing args into registers.
2828  // The InFlag in necessary since all emitted instructions must be
2829  // stuck together.
2830  for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i) {
2831    Chain = DAG.getCopyToReg(Chain, dl, RegsToPass[i].first,
2832                             RegsToPass[i].second, InFlag);
2833    InFlag = Chain.getValue(1);
2834  }
2835
2836  // MipsJmpLink = #chain, #target_address, #opt_in_flags...
2837  //             = Chain, Callee, Reg#1, Reg#2, ...
2838  //
2839  // Returns a chain & a flag for retval copy to use.
2840  SDVTList NodeTys = DAG.getVTList(MVT::Other, MVT::Glue);
2841  SmallVector<SDValue, 8> Ops;
2842  Ops.push_back(Chain);
2843  Ops.push_back(Callee);
2844
2845  // Add argument registers to the end of the list so that they are
2846  // known live into the call.
2847  for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i)
2848    Ops.push_back(DAG.getRegister(RegsToPass[i].first,
2849                                  RegsToPass[i].second.getValueType()));
2850
2851  // Add a register mask operand representing the call-preserved registers.
2852  const TargetRegisterInfo *TRI = getTargetMachine().getRegisterInfo();
2853  const uint32_t *Mask = TRI->getCallPreservedMask(CallConv);
2854  assert(Mask && "Missing call preserved mask for calling convention");
2855  Ops.push_back(DAG.getRegisterMask(Mask));
2856
2857  if (InFlag.getNode())
2858    Ops.push_back(InFlag);
2859
2860  Chain  = DAG.getNode(MipsISD::JmpLink, dl, NodeTys, &Ops[0], Ops.size());
2861  InFlag = Chain.getValue(1);
2862
2863  // Create the CALLSEQ_END node.
2864  Chain = DAG.getCALLSEQ_END(Chain,
2865                             DAG.getIntPtrConstant(NextStackOffset, true),
2866                             DAG.getIntPtrConstant(0, true), InFlag);
2867  InFlag = Chain.getValue(1);
2868
2869  // Handle result values, copying them out of physregs into vregs that we
2870  // return.
2871  return LowerCallResult(Chain, InFlag, CallConv, isVarArg,
2872                         Ins, dl, DAG, InVals);
2873}
2874
2875/// LowerCallResult - Lower the result values of a call into the
2876/// appropriate copies out of appropriate physical registers.
2877SDValue
2878MipsTargetLowering::LowerCallResult(SDValue Chain, SDValue InFlag,
2879                                    CallingConv::ID CallConv, bool isVarArg,
2880                                    const SmallVectorImpl<ISD::InputArg> &Ins,
2881                                    DebugLoc dl, SelectionDAG &DAG,
2882                                    SmallVectorImpl<SDValue> &InVals) const {
2883  // Assign locations to each value returned by this call.
2884  SmallVector<CCValAssign, 16> RVLocs;
2885  CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(),
2886		 getTargetMachine(), RVLocs, *DAG.getContext());
2887
2888  CCInfo.AnalyzeCallResult(Ins, RetCC_Mips);
2889
2890  // Copy all of the result registers out of their specified physreg.
2891  for (unsigned i = 0; i != RVLocs.size(); ++i) {
2892    Chain = DAG.getCopyFromReg(Chain, dl, RVLocs[i].getLocReg(),
2893                               RVLocs[i].getValVT(), InFlag).getValue(1);
2894    InFlag = Chain.getValue(2);
2895    InVals.push_back(Chain.getValue(0));
2896  }
2897
2898  return Chain;
2899}
2900
2901//===----------------------------------------------------------------------===//
2902//             Formal Arguments Calling Convention Implementation
2903//===----------------------------------------------------------------------===//
2904static void ReadByValArg(MachineFunction &MF, SDValue Chain, DebugLoc dl,
2905                         std::vector<SDValue>& OutChains,
2906                         SelectionDAG &DAG, unsigned NumWords, SDValue FIN,
2907                         const CCValAssign &VA, const ISD::ArgFlagsTy& Flags,
2908                         const Argument *FuncArg) {
2909  unsigned LocMem = VA.getLocMemOffset();
2910  unsigned FirstWord = LocMem / 4;
2911
2912  // copy register A0 - A3 to frame object
2913  for (unsigned i = 0; i < NumWords; ++i) {
2914    unsigned CurWord = FirstWord + i;
2915    if (CurWord >= O32IntRegsSize)
2916      break;
2917
2918    unsigned SrcReg = O32IntRegs[CurWord];
2919    unsigned Reg = AddLiveIn(MF, SrcReg, &Mips::CPURegsRegClass);
2920    SDValue StorePtr = DAG.getNode(ISD::ADD, dl, MVT::i32, FIN,
2921                                   DAG.getConstant(i * 4, MVT::i32));
2922    SDValue Store = DAG.getStore(Chain, dl, DAG.getRegister(Reg, MVT::i32),
2923                                 StorePtr, MachinePointerInfo(FuncArg, i * 4),
2924                                 false, false, 0);
2925    OutChains.push_back(Store);
2926  }
2927}
2928
2929// Create frame object on stack and copy registers used for byval passing to it.
2930static unsigned
2931CopyMips64ByValRegs(MachineFunction &MF, SDValue Chain, DebugLoc dl,
2932                    std::vector<SDValue>& OutChains, SelectionDAG &DAG,
2933                    const CCValAssign &VA, const ISD::ArgFlagsTy& Flags,
2934                    MachineFrameInfo *MFI, bool IsRegLoc,
2935                    SmallVectorImpl<SDValue> &InVals, MipsFunctionInfo *MipsFI,
2936                    EVT PtrTy, const Argument *FuncArg) {
2937  const uint16_t *Reg = Mips64IntRegs + 8;
2938  int FOOffset; // Frame object offset from virtual frame pointer.
2939
2940  if (IsRegLoc) {
2941    Reg = std::find(Mips64IntRegs, Mips64IntRegs + 8, VA.getLocReg());
2942    FOOffset = (Reg - Mips64IntRegs) * 8 - 8 * 8;
2943  }
2944  else
2945    FOOffset = VA.getLocMemOffset();
2946
2947  // Create frame object.
2948  unsigned NumRegs = (Flags.getByValSize() + 7) / 8;
2949  unsigned LastFI = MFI->CreateFixedObject(NumRegs * 8, FOOffset, true);
2950  SDValue FIN = DAG.getFrameIndex(LastFI, PtrTy);
2951  InVals.push_back(FIN);
2952
2953  // Copy arg registers.
2954  for (unsigned I = 0; (Reg != Mips64IntRegs + 8) && (I < NumRegs);
2955       ++Reg, ++I) {
2956    unsigned VReg = AddLiveIn(MF, *Reg, &Mips::CPU64RegsRegClass);
2957    SDValue StorePtr = DAG.getNode(ISD::ADD, dl, PtrTy, FIN,
2958                                   DAG.getConstant(I * 8, PtrTy));
2959    SDValue Store = DAG.getStore(Chain, dl, DAG.getRegister(VReg, MVT::i64),
2960                                 StorePtr, MachinePointerInfo(FuncArg, I * 8),
2961                                 false, false, 0);
2962    OutChains.push_back(Store);
2963  }
2964
2965  return LastFI;
2966}
2967
2968/// LowerFormalArguments - transform physical registers into virtual registers
2969/// and generate load operations for arguments places on the stack.
2970SDValue
2971MipsTargetLowering::LowerFormalArguments(SDValue Chain,
2972                                         CallingConv::ID CallConv,
2973                                         bool isVarArg,
2974                                      const SmallVectorImpl<ISD::InputArg> &Ins,
2975                                         DebugLoc dl, SelectionDAG &DAG,
2976                                         SmallVectorImpl<SDValue> &InVals)
2977                                          const {
2978  MachineFunction &MF = DAG.getMachineFunction();
2979  MachineFrameInfo *MFI = MF.getFrameInfo();
2980  MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
2981
2982  MipsFI->setVarArgsFrameIndex(0);
2983
2984  // Used with vargs to acumulate store chains.
2985  std::vector<SDValue> OutChains;
2986
2987  // Assign locations to all of the incoming arguments.
2988  SmallVector<CCValAssign, 16> ArgLocs;
2989  CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(),
2990                 getTargetMachine(), ArgLocs, *DAG.getContext());
2991
2992  if (IsO32)
2993    CCInfo.AnalyzeFormalArguments(Ins, CC_MipsO32);
2994  else
2995    CCInfo.AnalyzeFormalArguments(Ins, CC_Mips);
2996
2997  Function::const_arg_iterator FuncArg =
2998    DAG.getMachineFunction().getFunction()->arg_begin();
2999  int LastFI = 0;// MipsFI->LastInArgFI is 0 at the entry of this function.
3000
3001  for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i, ++FuncArg) {
3002    CCValAssign &VA = ArgLocs[i];
3003    EVT ValVT = VA.getValVT();
3004    ISD::ArgFlagsTy Flags = Ins[i].Flags;
3005    bool IsRegLoc = VA.isRegLoc();
3006
3007    if (Flags.isByVal()) {
3008      assert(Flags.getByValSize() &&
3009             "ByVal args of size 0 should have been ignored by front-end.");
3010      if (IsO32) {
3011        unsigned NumWords = (Flags.getByValSize() + 3) / 4;
3012        LastFI = MFI->CreateFixedObject(NumWords * 4, VA.getLocMemOffset(),
3013                                        true);
3014        SDValue FIN = DAG.getFrameIndex(LastFI, getPointerTy());
3015        InVals.push_back(FIN);
3016        ReadByValArg(MF, Chain, dl, OutChains, DAG, NumWords, FIN, VA, Flags,
3017                     &*FuncArg);
3018      } else // N32/64
3019        LastFI = CopyMips64ByValRegs(MF, Chain, dl, OutChains, DAG, VA, Flags,
3020                                     MFI, IsRegLoc, InVals, MipsFI,
3021                                     getPointerTy(), &*FuncArg);
3022      continue;
3023    }
3024
3025    // Arguments stored on registers
3026    if (IsRegLoc) {
3027      EVT RegVT = VA.getLocVT();
3028      unsigned ArgReg = VA.getLocReg();
3029      const TargetRegisterClass *RC;
3030
3031      if (RegVT == MVT::i32)
3032        RC = &Mips::CPURegsRegClass;
3033      else if (RegVT == MVT::i64)
3034        RC = &Mips::CPU64RegsRegClass;
3035      else if (RegVT == MVT::f32)
3036        RC = &Mips::FGR32RegClass;
3037      else if (RegVT == MVT::f64)
3038        RC = HasMips64 ? &Mips::FGR64RegClass : &Mips::AFGR64RegClass;
3039      else
3040        llvm_unreachable("RegVT not supported by FormalArguments Lowering");
3041
3042      // Transform the arguments stored on
3043      // physical registers into virtual ones
3044      unsigned Reg = AddLiveIn(DAG.getMachineFunction(), ArgReg, RC);
3045      SDValue ArgValue = DAG.getCopyFromReg(Chain, dl, Reg, RegVT);
3046
3047      // If this is an 8 or 16-bit value, it has been passed promoted
3048      // to 32 bits.  Insert an assert[sz]ext to capture this, then
3049      // truncate to the right size.
3050      if (VA.getLocInfo() != CCValAssign::Full) {
3051        unsigned Opcode = 0;
3052        if (VA.getLocInfo() == CCValAssign::SExt)
3053          Opcode = ISD::AssertSext;
3054        else if (VA.getLocInfo() == CCValAssign::ZExt)
3055          Opcode = ISD::AssertZext;
3056        if (Opcode)
3057          ArgValue = DAG.getNode(Opcode, dl, RegVT, ArgValue,
3058                                 DAG.getValueType(ValVT));
3059        ArgValue = DAG.getNode(ISD::TRUNCATE, dl, ValVT, ArgValue);
3060      }
3061
3062      // Handle floating point arguments passed in integer registers.
3063      if ((RegVT == MVT::i32 && ValVT == MVT::f32) ||
3064          (RegVT == MVT::i64 && ValVT == MVT::f64))
3065        ArgValue = DAG.getNode(ISD::BITCAST, dl, ValVT, ArgValue);
3066      else if (IsO32 && RegVT == MVT::i32 && ValVT == MVT::f64) {
3067        unsigned Reg2 = AddLiveIn(DAG.getMachineFunction(),
3068                                  getNextIntArgReg(ArgReg), RC);
3069        SDValue ArgValue2 = DAG.getCopyFromReg(Chain, dl, Reg2, RegVT);
3070        if (!Subtarget->isLittle())
3071          std::swap(ArgValue, ArgValue2);
3072        ArgValue = DAG.getNode(MipsISD::BuildPairF64, dl, MVT::f64,
3073                               ArgValue, ArgValue2);
3074      }
3075
3076      InVals.push_back(ArgValue);
3077    } else { // VA.isRegLoc()
3078
3079      // sanity check
3080      assert(VA.isMemLoc());
3081
3082      // The stack pointer offset is relative to the caller stack frame.
3083      LastFI = MFI->CreateFixedObject(ValVT.getSizeInBits()/8,
3084                                      VA.getLocMemOffset(), true);
3085
3086      // Create load nodes to retrieve arguments from the stack
3087      SDValue FIN = DAG.getFrameIndex(LastFI, getPointerTy());
3088      InVals.push_back(DAG.getLoad(ValVT, dl, Chain, FIN,
3089                                   MachinePointerInfo::getFixedStack(LastFI),
3090                                   false, false, false, 0));
3091    }
3092  }
3093
3094  // The mips ABIs for returning structs by value requires that we copy
3095  // the sret argument into $v0 for the return. Save the argument into
3096  // a virtual register so that we can access it from the return points.
3097  if (DAG.getMachineFunction().getFunction()->hasStructRetAttr()) {
3098    unsigned Reg = MipsFI->getSRetReturnReg();
3099    if (!Reg) {
3100      Reg = MF.getRegInfo().createVirtualRegister(getRegClassFor(MVT::i32));
3101      MipsFI->setSRetReturnReg(Reg);
3102    }
3103    SDValue Copy = DAG.getCopyToReg(DAG.getEntryNode(), dl, Reg, InVals[0]);
3104    Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Copy, Chain);
3105  }
3106
3107  if (isVarArg) {
3108    unsigned NumOfRegs = IsO32 ? 4 : 8;
3109    const uint16_t *ArgRegs = IsO32 ? O32IntRegs : Mips64IntRegs;
3110    unsigned Idx = CCInfo.getFirstUnallocated(ArgRegs, NumOfRegs);
3111    int FirstRegSlotOffset = IsO32 ? 0 : -64 ; // offset of $a0's slot.
3112    const TargetRegisterClass *RC = IsO32 ?
3113      (const TargetRegisterClass*)&Mips::CPURegsRegClass :
3114      (const TargetRegisterClass*)&Mips::CPU64RegsRegClass;
3115    unsigned RegSize = RC->getSize();
3116    int RegSlotOffset = FirstRegSlotOffset + Idx * RegSize;
3117
3118    // Offset of the first variable argument from stack pointer.
3119    int FirstVaArgOffset;
3120
3121    if (IsO32 || (Idx == NumOfRegs)) {
3122      FirstVaArgOffset =
3123        (CCInfo.getNextStackOffset() + RegSize - 1) / RegSize * RegSize;
3124    } else
3125      FirstVaArgOffset = RegSlotOffset;
3126
3127    // Record the frame index of the first variable argument
3128    // which is a value necessary to VASTART.
3129    LastFI = MFI->CreateFixedObject(RegSize, FirstVaArgOffset, true);
3130    MipsFI->setVarArgsFrameIndex(LastFI);
3131
3132    // Copy the integer registers that have not been used for argument passing
3133    // to the argument register save area. For O32, the save area is allocated
3134    // in the caller's stack frame, while for N32/64, it is allocated in the
3135    // callee's stack frame.
3136    for (int StackOffset = RegSlotOffset;
3137         Idx < NumOfRegs; ++Idx, StackOffset += RegSize) {
3138      unsigned Reg = AddLiveIn(DAG.getMachineFunction(), ArgRegs[Idx], RC);
3139      SDValue ArgValue = DAG.getCopyFromReg(Chain, dl, Reg,
3140                                            MVT::getIntegerVT(RegSize * 8));
3141      LastFI = MFI->CreateFixedObject(RegSize, StackOffset, true);
3142      SDValue PtrOff = DAG.getFrameIndex(LastFI, getPointerTy());
3143      OutChains.push_back(DAG.getStore(Chain, dl, ArgValue, PtrOff,
3144                                       MachinePointerInfo(), false, false, 0));
3145    }
3146  }
3147
3148  MipsFI->setLastInArgFI(LastFI);
3149
3150  // All stores are grouped in one node to allow the matching between
3151  // the size of Ins and InVals. This only happens when on varg functions
3152  if (!OutChains.empty()) {
3153    OutChains.push_back(Chain);
3154    Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
3155                        &OutChains[0], OutChains.size());
3156  }
3157
3158  return Chain;
3159}
3160
3161//===----------------------------------------------------------------------===//
3162//               Return Value Calling Convention Implementation
3163//===----------------------------------------------------------------------===//
3164
3165SDValue
3166MipsTargetLowering::LowerReturn(SDValue Chain,
3167                                CallingConv::ID CallConv, bool isVarArg,
3168                                const SmallVectorImpl<ISD::OutputArg> &Outs,
3169                                const SmallVectorImpl<SDValue> &OutVals,
3170                                DebugLoc dl, SelectionDAG &DAG) const {
3171
3172  // CCValAssign - represent the assignment of
3173  // the return value to a location
3174  SmallVector<CCValAssign, 16> RVLocs;
3175
3176  // CCState - Info about the registers and stack slot.
3177  CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(),
3178		 getTargetMachine(), RVLocs, *DAG.getContext());
3179
3180  // Analize return values.
3181  CCInfo.AnalyzeReturn(Outs, RetCC_Mips);
3182
3183  // If this is the first return lowered for this function, add
3184  // the regs to the liveout set for the function.
3185  if (DAG.getMachineFunction().getRegInfo().liveout_empty()) {
3186    for (unsigned i = 0; i != RVLocs.size(); ++i)
3187      if (RVLocs[i].isRegLoc())
3188        DAG.getMachineFunction().getRegInfo().addLiveOut(RVLocs[i].getLocReg());
3189  }
3190
3191  SDValue Flag;
3192
3193  // Copy the result values into the output registers.
3194  for (unsigned i = 0; i != RVLocs.size(); ++i) {
3195    CCValAssign &VA = RVLocs[i];
3196    assert(VA.isRegLoc() && "Can only return in registers!");
3197
3198    Chain = DAG.getCopyToReg(Chain, dl, VA.getLocReg(), OutVals[i], Flag);
3199
3200    // guarantee that all emitted copies are
3201    // stuck together, avoiding something bad
3202    Flag = Chain.getValue(1);
3203  }
3204
3205  // The mips ABIs for returning structs by value requires that we copy
3206  // the sret argument into $v0 for the return. We saved the argument into
3207  // a virtual register in the entry block, so now we copy the value out
3208  // and into $v0.
3209  if (DAG.getMachineFunction().getFunction()->hasStructRetAttr()) {
3210    MachineFunction &MF      = DAG.getMachineFunction();
3211    MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
3212    unsigned Reg = MipsFI->getSRetReturnReg();
3213
3214    if (!Reg)
3215      llvm_unreachable("sret virtual register not created in the entry block");
3216    SDValue Val = DAG.getCopyFromReg(Chain, dl, Reg, getPointerTy());
3217
3218    Chain = DAG.getCopyToReg(Chain, dl, Mips::V0, Val, Flag);
3219    Flag = Chain.getValue(1);
3220  }
3221
3222  // Return on Mips is always a "jr $ra"
3223  if (Flag.getNode())
3224    return DAG.getNode(MipsISD::Ret, dl, MVT::Other,
3225                       Chain, DAG.getRegister(Mips::RA, MVT::i32), Flag);
3226  else // Return Void
3227    return DAG.getNode(MipsISD::Ret, dl, MVT::Other,
3228                       Chain, DAG.getRegister(Mips::RA, MVT::i32));
3229}
3230
3231//===----------------------------------------------------------------------===//
3232//                           Mips Inline Assembly Support
3233//===----------------------------------------------------------------------===//
3234
3235/// getConstraintType - Given a constraint letter, return the type of
3236/// constraint it is for this target.
3237MipsTargetLowering::ConstraintType MipsTargetLowering::
3238getConstraintType(const std::string &Constraint) const
3239{
3240  // Mips specific constrainy
3241  // GCC config/mips/constraints.md
3242  //
3243  // 'd' : An address register. Equivalent to r
3244  //       unless generating MIPS16 code.
3245  // 'y' : Equivalent to r; retained for
3246  //       backwards compatibility.
3247  // 'c' : A register suitable for use in an indirect
3248  //       jump. This will always be $25 for -mabicalls.
3249  // 'l' : The lo register. 1 word storage.
3250  // 'x' : The hilo register pair. Double word storage.
3251  if (Constraint.size() == 1) {
3252    switch (Constraint[0]) {
3253      default : break;
3254      case 'd':
3255      case 'y':
3256      case 'f':
3257      case 'c':
3258      case 'l':
3259      case 'x':
3260        return C_RegisterClass;
3261    }
3262  }
3263  return TargetLowering::getConstraintType(Constraint);
3264}
3265
3266/// Examine constraint type and operand type and determine a weight value.
3267/// This object must already have been set up with the operand type
3268/// and the current alternative constraint selected.
3269TargetLowering::ConstraintWeight
3270MipsTargetLowering::getSingleConstraintMatchWeight(
3271    AsmOperandInfo &info, const char *constraint) const {
3272  ConstraintWeight weight = CW_Invalid;
3273  Value *CallOperandVal = info.CallOperandVal;
3274    // If we don't have a value, we can't do a match,
3275    // but allow it at the lowest weight.
3276  if (CallOperandVal == NULL)
3277    return CW_Default;
3278  Type *type = CallOperandVal->getType();
3279  // Look at the constraint type.
3280  switch (*constraint) {
3281  default:
3282    weight = TargetLowering::getSingleConstraintMatchWeight(info, constraint);
3283    break;
3284  case 'd':
3285  case 'y':
3286    if (type->isIntegerTy())
3287      weight = CW_Register;
3288    break;
3289  case 'f':
3290    if (type->isFloatTy())
3291      weight = CW_Register;
3292    break;
3293  case 'c': // $25 for indirect jumps
3294  case 'l': // lo register
3295  case 'x': // hilo register pair
3296      if (type->isIntegerTy())
3297      weight = CW_SpecificReg;
3298      break;
3299  case 'I': // signed 16 bit immediate
3300  case 'J': // integer zero
3301  case 'K': // unsigned 16 bit immediate
3302  case 'L': // signed 32 bit immediate where lower 16 bits are 0
3303  case 'N': // immediate in the range of -65535 to -1 (inclusive)
3304  case 'O': // signed 15 bit immediate (+- 16383)
3305  case 'P': // immediate in the range of 65535 to 1 (inclusive)
3306    if (isa<ConstantInt>(CallOperandVal))
3307      weight = CW_Constant;
3308    break;
3309  }
3310  return weight;
3311}
3312
3313/// Given a register class constraint, like 'r', if this corresponds directly
3314/// to an LLVM register class, return a register of 0 and the register class
3315/// pointer.
3316std::pair<unsigned, const TargetRegisterClass*> MipsTargetLowering::
3317getRegForInlineAsmConstraint(const std::string &Constraint, EVT VT) const
3318{
3319  if (Constraint.size() == 1) {
3320    switch (Constraint[0]) {
3321    case 'd': // Address register. Same as 'r' unless generating MIPS16 code.
3322    case 'y': // Same as 'r'. Exists for compatibility.
3323    case 'r':
3324      if (VT == MVT::i32 || VT == MVT::i16 || VT == MVT::i8)
3325        return std::make_pair(0U, &Mips::CPURegsRegClass);
3326      if (VT == MVT::i64 && HasMips64)
3327        return std::make_pair(0U, &Mips::CPU64RegsRegClass);
3328      // This will generate an error message
3329      return std::make_pair(0u, static_cast<const TargetRegisterClass*>(0));
3330    case 'f':
3331      if (VT == MVT::f32)
3332        return std::make_pair(0U, &Mips::FGR32RegClass);
3333      if ((VT == MVT::f64) && (!Subtarget->isSingleFloat())) {
3334        if (Subtarget->isFP64bit())
3335          return std::make_pair(0U, &Mips::FGR64RegClass);
3336        return std::make_pair(0U, &Mips::AFGR64RegClass);
3337      }
3338      break;
3339    case 'c': // register suitable for indirect jump
3340      if (VT == MVT::i32)
3341        return std::make_pair((unsigned)Mips::T9, &Mips::CPURegsRegClass);
3342      assert(VT == MVT::i64 && "Unexpected type.");
3343      return std::make_pair((unsigned)Mips::T9_64, &Mips::CPU64RegsRegClass);
3344    case 'l': // register suitable for indirect jump
3345      if (VT == MVT::i32)
3346        return std::make_pair((unsigned)Mips::LO, &Mips::HILORegClass);
3347      return std::make_pair((unsigned)Mips::LO64, &Mips::HILO64RegClass);
3348    case 'x': // register suitable for indirect jump
3349      // Fixme: Not triggering the use of both hi and low
3350      // This will generate an error message
3351      return std::make_pair(0u, static_cast<const TargetRegisterClass*>(0));
3352    }
3353  }
3354  return TargetLowering::getRegForInlineAsmConstraint(Constraint, VT);
3355}
3356
3357/// LowerAsmOperandForConstraint - Lower the specified operand into the Ops
3358/// vector.  If it is invalid, don't add anything to Ops.
3359void MipsTargetLowering::LowerAsmOperandForConstraint(SDValue Op,
3360                                                     std::string &Constraint,
3361                                                     std::vector<SDValue>&Ops,
3362                                                     SelectionDAG &DAG) const {
3363  SDValue Result(0, 0);
3364
3365  // Only support length 1 constraints for now.
3366  if (Constraint.length() > 1) return;
3367
3368  char ConstraintLetter = Constraint[0];
3369  switch (ConstraintLetter) {
3370  default: break; // This will fall through to the generic implementation
3371  case 'I': // Signed 16 bit constant
3372    // If this fails, the parent routine will give an error
3373    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
3374      EVT Type = Op.getValueType();
3375      int64_t Val = C->getSExtValue();
3376      if (isInt<16>(Val)) {
3377        Result = DAG.getTargetConstant(Val, Type);
3378        break;
3379      }
3380    }
3381    return;
3382  case 'J': // integer zero
3383    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
3384      EVT Type = Op.getValueType();
3385      int64_t Val = C->getZExtValue();
3386      if (Val == 0) {
3387        Result = DAG.getTargetConstant(0, Type);
3388        break;
3389      }
3390    }
3391    return;
3392  case 'K': // unsigned 16 bit immediate
3393    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
3394      EVT Type = Op.getValueType();
3395      uint64_t Val = (uint64_t)C->getZExtValue();
3396      if (isUInt<16>(Val)) {
3397        Result = DAG.getTargetConstant(Val, Type);
3398        break;
3399      }
3400    }
3401    return;
3402  case 'L': // signed 32 bit immediate where lower 16 bits are 0
3403    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
3404      EVT Type = Op.getValueType();
3405      int64_t Val = C->getSExtValue();
3406      if ((isInt<32>(Val)) && ((Val & 0xffff) == 0)){
3407        Result = DAG.getTargetConstant(Val, Type);
3408        break;
3409      }
3410    }
3411    return;
3412  case 'N': // immediate in the range of -65535 to -1 (inclusive)
3413    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
3414      EVT Type = Op.getValueType();
3415      int64_t Val = C->getSExtValue();
3416      if ((Val >= -65535) && (Val <= -1)) {
3417        Result = DAG.getTargetConstant(Val, Type);
3418        break;
3419      }
3420    }
3421    return;
3422  case 'O': // signed 15 bit immediate
3423    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
3424      EVT Type = Op.getValueType();
3425      int64_t Val = C->getSExtValue();
3426      if ((isInt<15>(Val))) {
3427        Result = DAG.getTargetConstant(Val, Type);
3428        break;
3429      }
3430    }
3431    return;
3432  case 'P': // immediate in the range of 1 to 65535 (inclusive)
3433    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
3434      EVT Type = Op.getValueType();
3435      int64_t Val = C->getSExtValue();
3436      if ((Val <= 65535) && (Val >= 1)) {
3437        Result = DAG.getTargetConstant(Val, Type);
3438        break;
3439      }
3440    }
3441    return;
3442  }
3443
3444  if (Result.getNode()) {
3445    Ops.push_back(Result);
3446    return;
3447  }
3448
3449  TargetLowering::LowerAsmOperandForConstraint(Op, Constraint, Ops, DAG);
3450}
3451
3452bool
3453MipsTargetLowering::isOffsetFoldingLegal(const GlobalAddressSDNode *GA) const {
3454  // The Mips target isn't yet aware of offsets.
3455  return false;
3456}
3457
3458bool MipsTargetLowering::isFPImmLegal(const APFloat &Imm, EVT VT) const {
3459  if (VT != MVT::f32 && VT != MVT::f64)
3460    return false;
3461  if (Imm.isNegZero())
3462    return false;
3463  return Imm.isZero();
3464}
3465
3466unsigned MipsTargetLowering::getJumpTableEncoding() const {
3467  if (IsN64)
3468    return MachineJumpTableInfo::EK_GPRel64BlockAddress;
3469
3470  return TargetLowering::getJumpTableEncoding();
3471}
3472