MipsISelLowering.cpp revision 2fbe90cf93fcb153ac1d651c764785c9b09887f6
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#define DEBUG_TYPE "mips-lower"
15#include "MipsISelLowering.h"
16#include "InstPrinter/MipsInstPrinter.h"
17#include "MCTargetDesc/MipsBaseInfo.h"
18#include "MipsMachineFunction.h"
19#include "MipsSubtarget.h"
20#include "MipsTargetMachine.h"
21#include "MipsTargetObjectFile.h"
22#include "llvm/ADT/Statistic.h"
23#include "llvm/CodeGen/CallingConvLower.h"
24#include "llvm/CodeGen/MachineFrameInfo.h"
25#include "llvm/CodeGen/MachineFunction.h"
26#include "llvm/CodeGen/MachineInstrBuilder.h"
27#include "llvm/CodeGen/MachineRegisterInfo.h"
28#include "llvm/CodeGen/SelectionDAGISel.h"
29#include "llvm/CodeGen/ValueTypes.h"
30#include "llvm/IR/CallingConv.h"
31#include "llvm/IR/DerivedTypes.h"
32#include "llvm/IR/GlobalVariable.h"
33#include "llvm/Support/CommandLine.h"
34#include "llvm/Support/Debug.h"
35#include "llvm/Support/ErrorHandling.h"
36#include "llvm/Support/raw_ostream.h"
37
38using namespace llvm;
39
40STATISTIC(NumTailCalls, "Number of tail calls");
41
42static cl::opt<bool>
43LargeGOT("mxgot", cl::Hidden,
44         cl::desc("MIPS: Enable GOT larger than 64k."), cl::init(false));
45
46static const uint16_t O32IntRegs[4] = {
47  Mips::A0, Mips::A1, Mips::A2, Mips::A3
48};
49
50static const uint16_t Mips64IntRegs[8] = {
51  Mips::A0_64, Mips::A1_64, Mips::A2_64, Mips::A3_64,
52  Mips::T0_64, Mips::T1_64, Mips::T2_64, Mips::T3_64
53};
54
55static const uint16_t Mips64DPRegs[8] = {
56  Mips::D12_64, Mips::D13_64, Mips::D14_64, Mips::D15_64,
57  Mips::D16_64, Mips::D17_64, Mips::D18_64, Mips::D19_64
58};
59
60// If I is a shifted mask, set the size (Size) and the first bit of the
61// mask (Pos), and return true.
62// For example, if I is 0x003ff800, (Pos, Size) = (11, 11).
63static bool isShiftedMask(uint64_t I, uint64_t &Pos, uint64_t &Size) {
64  if (!isShiftedMask_64(I))
65     return false;
66
67  Size = CountPopulation_64(I);
68  Pos = CountTrailingZeros_64(I);
69  return true;
70}
71
72SDValue MipsTargetLowering::getGlobalReg(SelectionDAG &DAG, EVT Ty) const {
73  MipsFunctionInfo *FI = DAG.getMachineFunction().getInfo<MipsFunctionInfo>();
74  return DAG.getRegister(FI->getGlobalBaseReg(), Ty);
75}
76
77static SDValue getTargetNode(SDValue Op, SelectionDAG &DAG, unsigned Flag) {
78  EVT Ty = Op.getValueType();
79
80  if (GlobalAddressSDNode *N = dyn_cast<GlobalAddressSDNode>(Op))
81    return DAG.getTargetGlobalAddress(N->getGlobal(), Op.getDebugLoc(), Ty, 0,
82                                      Flag);
83  if (ExternalSymbolSDNode *N = dyn_cast<ExternalSymbolSDNode>(Op))
84    return DAG.getTargetExternalSymbol(N->getSymbol(), Ty, Flag);
85  if (BlockAddressSDNode *N = dyn_cast<BlockAddressSDNode>(Op))
86    return DAG.getTargetBlockAddress(N->getBlockAddress(), Ty, 0, Flag);
87  if (JumpTableSDNode *N = dyn_cast<JumpTableSDNode>(Op))
88    return DAG.getTargetJumpTable(N->getIndex(), Ty, Flag);
89  if (ConstantPoolSDNode *N = dyn_cast<ConstantPoolSDNode>(Op))
90    return DAG.getTargetConstantPool(N->getConstVal(), Ty, N->getAlignment(),
91                                     N->getOffset(), Flag);
92
93  llvm_unreachable("Unexpected node type.");
94  return SDValue();
95}
96
97static SDValue getAddrNonPIC(SDValue Op, SelectionDAG &DAG) {
98  DebugLoc DL = Op.getDebugLoc();
99  EVT Ty = Op.getValueType();
100  SDValue Hi = getTargetNode(Op, DAG, MipsII::MO_ABS_HI);
101  SDValue Lo = getTargetNode(Op, DAG, MipsII::MO_ABS_LO);
102  return DAG.getNode(ISD::ADD, DL, Ty,
103                     DAG.getNode(MipsISD::Hi, DL, Ty, Hi),
104                     DAG.getNode(MipsISD::Lo, DL, Ty, Lo));
105}
106
107SDValue MipsTargetLowering::getAddrLocal(SDValue Op, SelectionDAG &DAG,
108                                         bool HasMips64) const {
109  DebugLoc DL = Op.getDebugLoc();
110  EVT Ty = Op.getValueType();
111  unsigned GOTFlag = HasMips64 ? MipsII::MO_GOT_PAGE : MipsII::MO_GOT;
112  SDValue GOT = DAG.getNode(MipsISD::Wrapper, DL, Ty, getGlobalReg(DAG, Ty),
113                            getTargetNode(Op, DAG, GOTFlag));
114  SDValue Load = DAG.getLoad(Ty, DL, DAG.getEntryNode(), GOT,
115                             MachinePointerInfo::getGOT(), false, false, false,
116                             0);
117  unsigned LoFlag = HasMips64 ? MipsII::MO_GOT_OFST : MipsII::MO_ABS_LO;
118  SDValue Lo = DAG.getNode(MipsISD::Lo, DL, Ty, getTargetNode(Op, DAG, LoFlag));
119  return DAG.getNode(ISD::ADD, DL, Ty, Load, Lo);
120}
121
122SDValue MipsTargetLowering::getAddrGlobal(SDValue Op, SelectionDAG &DAG,
123                                          unsigned Flag) const {
124  DebugLoc DL = Op.getDebugLoc();
125  EVT Ty = Op.getValueType();
126  SDValue Tgt = DAG.getNode(MipsISD::Wrapper, DL, Ty, getGlobalReg(DAG, Ty),
127                            getTargetNode(Op, DAG, Flag));
128  return DAG.getLoad(Ty, DL, DAG.getEntryNode(), Tgt,
129                     MachinePointerInfo::getGOT(), false, false, false, 0);
130}
131
132SDValue MipsTargetLowering::getAddrGlobalLargeGOT(SDValue Op, SelectionDAG &DAG,
133                                                  unsigned HiFlag,
134                                                  unsigned LoFlag) const {
135  DebugLoc DL = Op.getDebugLoc();
136  EVT Ty = Op.getValueType();
137  SDValue Hi = DAG.getNode(MipsISD::Hi, DL, Ty, getTargetNode(Op, DAG, HiFlag));
138  Hi = DAG.getNode(ISD::ADD, DL, Ty, Hi, getGlobalReg(DAG, Ty));
139  SDValue Wrapper = DAG.getNode(MipsISD::Wrapper, DL, Ty, Hi,
140                                getTargetNode(Op, DAG, LoFlag));
141  return DAG.getLoad(Ty, DL, DAG.getEntryNode(), Wrapper,
142                     MachinePointerInfo::getGOT(), false, false, false, 0);
143}
144
145const char *MipsTargetLowering::getTargetNodeName(unsigned Opcode) const {
146  switch (Opcode) {
147  case MipsISD::JmpLink:           return "MipsISD::JmpLink";
148  case MipsISD::TailCall:          return "MipsISD::TailCall";
149  case MipsISD::Hi:                return "MipsISD::Hi";
150  case MipsISD::Lo:                return "MipsISD::Lo";
151  case MipsISD::GPRel:             return "MipsISD::GPRel";
152  case MipsISD::ThreadPointer:     return "MipsISD::ThreadPointer";
153  case MipsISD::Ret:               return "MipsISD::Ret";
154  case MipsISD::EH_RETURN:         return "MipsISD::EH_RETURN";
155  case MipsISD::FPBrcond:          return "MipsISD::FPBrcond";
156  case MipsISD::FPCmp:             return "MipsISD::FPCmp";
157  case MipsISD::CMovFP_T:          return "MipsISD::CMovFP_T";
158  case MipsISD::CMovFP_F:          return "MipsISD::CMovFP_F";
159  case MipsISD::FPRound:           return "MipsISD::FPRound";
160  case MipsISD::ExtractLOHI:       return "MipsISD::ExtractLOHI";
161  case MipsISD::InsertLOHI:        return "MipsISD::InsertLOHI";
162  case MipsISD::Mult:              return "MipsISD::Mult";
163  case MipsISD::Multu:             return "MipsISD::Multu";
164  case MipsISD::MAdd:              return "MipsISD::MAdd";
165  case MipsISD::MAddu:             return "MipsISD::MAddu";
166  case MipsISD::MSub:              return "MipsISD::MSub";
167  case MipsISD::MSubu:             return "MipsISD::MSubu";
168  case MipsISD::DivRem:            return "MipsISD::DivRem";
169  case MipsISD::DivRemU:           return "MipsISD::DivRemU";
170  case MipsISD::DivRem16:          return "MipsISD::DivRem16";
171  case MipsISD::DivRemU16:         return "MipsISD::DivRemU16";
172  case MipsISD::BuildPairF64:      return "MipsISD::BuildPairF64";
173  case MipsISD::ExtractElementF64: return "MipsISD::ExtractElementF64";
174  case MipsISD::Wrapper:           return "MipsISD::Wrapper";
175  case MipsISD::Sync:              return "MipsISD::Sync";
176  case MipsISD::Ext:               return "MipsISD::Ext";
177  case MipsISD::Ins:               return "MipsISD::Ins";
178  case MipsISD::LWL:               return "MipsISD::LWL";
179  case MipsISD::LWR:               return "MipsISD::LWR";
180  case MipsISD::SWL:               return "MipsISD::SWL";
181  case MipsISD::SWR:               return "MipsISD::SWR";
182  case MipsISD::LDL:               return "MipsISD::LDL";
183  case MipsISD::LDR:               return "MipsISD::LDR";
184  case MipsISD::SDL:               return "MipsISD::SDL";
185  case MipsISD::SDR:               return "MipsISD::SDR";
186  case MipsISD::EXTP:              return "MipsISD::EXTP";
187  case MipsISD::EXTPDP:            return "MipsISD::EXTPDP";
188  case MipsISD::EXTR_S_H:          return "MipsISD::EXTR_S_H";
189  case MipsISD::EXTR_W:            return "MipsISD::EXTR_W";
190  case MipsISD::EXTR_R_W:          return "MipsISD::EXTR_R_W";
191  case MipsISD::EXTR_RS_W:         return "MipsISD::EXTR_RS_W";
192  case MipsISD::SHILO:             return "MipsISD::SHILO";
193  case MipsISD::MTHLIP:            return "MipsISD::MTHLIP";
194  case MipsISD::MULT:              return "MipsISD::MULT";
195  case MipsISD::MULTU:             return "MipsISD::MULTU";
196  case MipsISD::MADD_DSP:          return "MipsISD::MADD_DSP";
197  case MipsISD::MADDU_DSP:         return "MipsISD::MADDU_DSP";
198  case MipsISD::MSUB_DSP:          return "MipsISD::MSUB_DSP";
199  case MipsISD::MSUBU_DSP:         return "MipsISD::MSUBU_DSP";
200  default:                         return NULL;
201  }
202}
203
204MipsTargetLowering::
205MipsTargetLowering(MipsTargetMachine &TM)
206  : TargetLowering(TM, new MipsTargetObjectFile()),
207    Subtarget(&TM.getSubtarget<MipsSubtarget>()),
208    HasMips64(Subtarget->hasMips64()), IsN64(Subtarget->isABI_N64()),
209    IsO32(Subtarget->isABI_O32()) {
210  // Mips does not have i1 type, so use i32 for
211  // setcc operations results (slt, sgt, ...).
212  setBooleanContents(ZeroOrOneBooleanContent);
213  setBooleanVectorContents(ZeroOrOneBooleanContent); // FIXME: Is this correct?
214
215  // Load extented operations for i1 types must be promoted
216  setLoadExtAction(ISD::EXTLOAD,  MVT::i1,  Promote);
217  setLoadExtAction(ISD::ZEXTLOAD, MVT::i1,  Promote);
218  setLoadExtAction(ISD::SEXTLOAD, MVT::i1,  Promote);
219
220  // MIPS doesn't have extending float->double load/store
221  setLoadExtAction(ISD::EXTLOAD, MVT::f32, Expand);
222  setTruncStoreAction(MVT::f64, MVT::f32, Expand);
223
224  // Used by legalize types to correctly generate the setcc result.
225  // Without this, every float setcc comes with a AND/OR with the result,
226  // we don't want this, since the fpcmp result goes to a flag register,
227  // which is used implicitly by brcond and select operations.
228  AddPromotedToType(ISD::SETCC, MVT::i1, MVT::i32);
229
230  // Mips Custom Operations
231  setOperationAction(ISD::BR_JT,              MVT::Other, Custom);
232  setOperationAction(ISD::GlobalAddress,      MVT::i32,   Custom);
233  setOperationAction(ISD::BlockAddress,       MVT::i32,   Custom);
234  setOperationAction(ISD::GlobalTLSAddress,   MVT::i32,   Custom);
235  setOperationAction(ISD::JumpTable,          MVT::i32,   Custom);
236  setOperationAction(ISD::ConstantPool,       MVT::i32,   Custom);
237  setOperationAction(ISD::SELECT,             MVT::f32,   Custom);
238  setOperationAction(ISD::SELECT,             MVT::f64,   Custom);
239  setOperationAction(ISD::SELECT,             MVT::i32,   Custom);
240  setOperationAction(ISD::SELECT_CC,          MVT::f32,   Custom);
241  setOperationAction(ISD::SELECT_CC,          MVT::f64,   Custom);
242  setOperationAction(ISD::SETCC,              MVT::f32,   Custom);
243  setOperationAction(ISD::SETCC,              MVT::f64,   Custom);
244  setOperationAction(ISD::BRCOND,             MVT::Other, Custom);
245  setOperationAction(ISD::VASTART,            MVT::Other, Custom);
246  setOperationAction(ISD::FCOPYSIGN,          MVT::f32,   Custom);
247  setOperationAction(ISD::FCOPYSIGN,          MVT::f64,   Custom);
248
249  if (!TM.Options.NoNaNsFPMath) {
250    setOperationAction(ISD::FABS,             MVT::f32,   Custom);
251    setOperationAction(ISD::FABS,             MVT::f64,   Custom);
252  }
253
254  if (HasMips64) {
255    setOperationAction(ISD::GlobalAddress,      MVT::i64,   Custom);
256    setOperationAction(ISD::BlockAddress,       MVT::i64,   Custom);
257    setOperationAction(ISD::GlobalTLSAddress,   MVT::i64,   Custom);
258    setOperationAction(ISD::JumpTable,          MVT::i64,   Custom);
259    setOperationAction(ISD::ConstantPool,       MVT::i64,   Custom);
260    setOperationAction(ISD::SELECT,             MVT::i64,   Custom);
261    setOperationAction(ISD::LOAD,               MVT::i64,   Custom);
262    setOperationAction(ISD::STORE,              MVT::i64,   Custom);
263  }
264
265  if (!HasMips64) {
266    setOperationAction(ISD::SHL_PARTS,          MVT::i32,   Custom);
267    setOperationAction(ISD::SRA_PARTS,          MVT::i32,   Custom);
268    setOperationAction(ISD::SRL_PARTS,          MVT::i32,   Custom);
269  }
270
271  setOperationAction(ISD::ADD,                MVT::i32,   Custom);
272  if (HasMips64)
273    setOperationAction(ISD::ADD,                MVT::i64,   Custom);
274
275  setOperationAction(ISD::SDIV, MVT::i32, Expand);
276  setOperationAction(ISD::SREM, MVT::i32, Expand);
277  setOperationAction(ISD::UDIV, MVT::i32, Expand);
278  setOperationAction(ISD::UREM, MVT::i32, Expand);
279  setOperationAction(ISD::SDIV, MVT::i64, Expand);
280  setOperationAction(ISD::SREM, MVT::i64, Expand);
281  setOperationAction(ISD::UDIV, MVT::i64, Expand);
282  setOperationAction(ISD::UREM, MVT::i64, Expand);
283
284  // Operations not directly supported by Mips.
285  setOperationAction(ISD::BR_CC,             MVT::f32,   Expand);
286  setOperationAction(ISD::BR_CC,             MVT::f64,   Expand);
287  setOperationAction(ISD::BR_CC,             MVT::i32,   Expand);
288  setOperationAction(ISD::BR_CC,             MVT::i64,   Expand);
289  setOperationAction(ISD::SELECT_CC,         MVT::Other, Expand);
290  setOperationAction(ISD::UINT_TO_FP,        MVT::i32,   Expand);
291  setOperationAction(ISD::UINT_TO_FP,        MVT::i64,   Expand);
292  setOperationAction(ISD::FP_TO_UINT,        MVT::i32,   Expand);
293  setOperationAction(ISD::FP_TO_UINT,        MVT::i64,   Expand);
294  setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i1,    Expand);
295  setOperationAction(ISD::CTPOP,             MVT::i32,   Expand);
296  setOperationAction(ISD::CTPOP,             MVT::i64,   Expand);
297  setOperationAction(ISD::CTTZ,              MVT::i32,   Expand);
298  setOperationAction(ISD::CTTZ,              MVT::i64,   Expand);
299  setOperationAction(ISD::CTTZ_ZERO_UNDEF,   MVT::i32,   Expand);
300  setOperationAction(ISD::CTTZ_ZERO_UNDEF,   MVT::i64,   Expand);
301  setOperationAction(ISD::CTLZ_ZERO_UNDEF,   MVT::i32,   Expand);
302  setOperationAction(ISD::CTLZ_ZERO_UNDEF,   MVT::i64,   Expand);
303  setOperationAction(ISD::ROTL,              MVT::i32,   Expand);
304  setOperationAction(ISD::ROTL,              MVT::i64,   Expand);
305  setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32,  Expand);
306  setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i64,  Expand);
307
308  if (!Subtarget->hasMips32r2())
309    setOperationAction(ISD::ROTR, MVT::i32,   Expand);
310
311  if (!Subtarget->hasMips64r2())
312    setOperationAction(ISD::ROTR, MVT::i64,   Expand);
313
314  setOperationAction(ISD::FSIN,              MVT::f32,   Expand);
315  setOperationAction(ISD::FSIN,              MVT::f64,   Expand);
316  setOperationAction(ISD::FCOS,              MVT::f32,   Expand);
317  setOperationAction(ISD::FCOS,              MVT::f64,   Expand);
318  setOperationAction(ISD::FSINCOS,           MVT::f32,   Expand);
319  setOperationAction(ISD::FSINCOS,           MVT::f64,   Expand);
320  setOperationAction(ISD::FPOWI,             MVT::f32,   Expand);
321  setOperationAction(ISD::FPOW,              MVT::f32,   Expand);
322  setOperationAction(ISD::FPOW,              MVT::f64,   Expand);
323  setOperationAction(ISD::FLOG,              MVT::f32,   Expand);
324  setOperationAction(ISD::FLOG2,             MVT::f32,   Expand);
325  setOperationAction(ISD::FLOG10,            MVT::f32,   Expand);
326  setOperationAction(ISD::FEXP,              MVT::f32,   Expand);
327  setOperationAction(ISD::FMA,               MVT::f32,   Expand);
328  setOperationAction(ISD::FMA,               MVT::f64,   Expand);
329  setOperationAction(ISD::FREM,              MVT::f32,   Expand);
330  setOperationAction(ISD::FREM,              MVT::f64,   Expand);
331
332  if (!TM.Options.NoNaNsFPMath) {
333    setOperationAction(ISD::FNEG,             MVT::f32,   Expand);
334    setOperationAction(ISD::FNEG,             MVT::f64,   Expand);
335  }
336
337  setOperationAction(ISD::EXCEPTIONADDR,     MVT::i32, Expand);
338  setOperationAction(ISD::EXCEPTIONADDR,     MVT::i64, Expand);
339  setOperationAction(ISD::EHSELECTION,       MVT::i32, Expand);
340  setOperationAction(ISD::EHSELECTION,       MVT::i64, Expand);
341
342  setOperationAction(ISD::EH_RETURN, MVT::Other, Custom);
343
344  setOperationAction(ISD::VAARG,             MVT::Other, Expand);
345  setOperationAction(ISD::VACOPY,            MVT::Other, Expand);
346  setOperationAction(ISD::VAEND,             MVT::Other, Expand);
347
348  // Use the default for now
349  setOperationAction(ISD::STACKSAVE,         MVT::Other, Expand);
350  setOperationAction(ISD::STACKRESTORE,      MVT::Other, Expand);
351
352  setOperationAction(ISD::ATOMIC_LOAD,       MVT::i32,    Expand);
353  setOperationAction(ISD::ATOMIC_LOAD,       MVT::i64,    Expand);
354  setOperationAction(ISD::ATOMIC_STORE,      MVT::i32,    Expand);
355  setOperationAction(ISD::ATOMIC_STORE,      MVT::i64,    Expand);
356
357  setInsertFencesForAtomic(true);
358
359  if (!Subtarget->hasSEInReg()) {
360    setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i8,  Expand);
361    setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i16, Expand);
362  }
363
364  if (!Subtarget->hasBitCount()) {
365    setOperationAction(ISD::CTLZ, MVT::i32, Expand);
366    setOperationAction(ISD::CTLZ, MVT::i64, Expand);
367  }
368
369  if (!Subtarget->hasSwap()) {
370    setOperationAction(ISD::BSWAP, MVT::i32, Expand);
371    setOperationAction(ISD::BSWAP, MVT::i64, Expand);
372  }
373
374  if (HasMips64) {
375    setLoadExtAction(ISD::SEXTLOAD, MVT::i32, Custom);
376    setLoadExtAction(ISD::ZEXTLOAD, MVT::i32, Custom);
377    setLoadExtAction(ISD::EXTLOAD, MVT::i32, Custom);
378    setTruncStoreAction(MVT::i64, MVT::i32, Custom);
379  }
380
381  setTargetDAGCombine(ISD::SDIVREM);
382  setTargetDAGCombine(ISD::UDIVREM);
383  setTargetDAGCombine(ISD::SELECT);
384  setTargetDAGCombine(ISD::AND);
385  setTargetDAGCombine(ISD::OR);
386  setTargetDAGCombine(ISD::ADD);
387
388  setMinFunctionAlignment(HasMips64 ? 3 : 2);
389
390  setStackPointerRegisterToSaveRestore(IsN64 ? Mips::SP_64 : Mips::SP);
391
392  setExceptionPointerRegister(IsN64 ? Mips::A0_64 : Mips::A0);
393  setExceptionSelectorRegister(IsN64 ? Mips::A1_64 : Mips::A1);
394
395  MaxStoresPerMemcpy = 16;
396}
397
398const MipsTargetLowering *MipsTargetLowering::create(MipsTargetMachine &TM) {
399  if (TM.getSubtargetImpl()->inMips16Mode())
400    return llvm::createMips16TargetLowering(TM);
401
402  return llvm::createMipsSETargetLowering(TM);
403}
404
405EVT MipsTargetLowering::getSetCCResultType(EVT VT) const {
406  if (!VT.isVector())
407    return MVT::i32;
408  return VT.changeVectorElementTypeToInteger();
409}
410
411static SDValue performDivRemCombine(SDNode *N, SelectionDAG &DAG,
412                                    TargetLowering::DAGCombinerInfo &DCI,
413                                    const MipsSubtarget *Subtarget) {
414  if (DCI.isBeforeLegalizeOps())
415    return SDValue();
416
417  EVT Ty = N->getValueType(0);
418  unsigned LO = (Ty == MVT::i32) ? Mips::LO : Mips::LO64;
419  unsigned HI = (Ty == MVT::i32) ? Mips::HI : Mips::HI64;
420  unsigned Opc = N->getOpcode() == ISD::SDIVREM ? MipsISD::DivRem16 :
421                                                  MipsISD::DivRemU16;
422  DebugLoc DL = N->getDebugLoc();
423
424  SDValue DivRem = DAG.getNode(Opc, DL, MVT::Glue,
425                               N->getOperand(0), N->getOperand(1));
426  SDValue InChain = DAG.getEntryNode();
427  SDValue InGlue = DivRem;
428
429  // insert MFLO
430  if (N->hasAnyUseOfValue(0)) {
431    SDValue CopyFromLo = DAG.getCopyFromReg(InChain, DL, LO, Ty,
432                                            InGlue);
433    DAG.ReplaceAllUsesOfValueWith(SDValue(N, 0), CopyFromLo);
434    InChain = CopyFromLo.getValue(1);
435    InGlue = CopyFromLo.getValue(2);
436  }
437
438  // insert MFHI
439  if (N->hasAnyUseOfValue(1)) {
440    SDValue CopyFromHi = DAG.getCopyFromReg(InChain, DL,
441                                            HI, Ty, InGlue);
442    DAG.ReplaceAllUsesOfValueWith(SDValue(N, 1), CopyFromHi);
443  }
444
445  return SDValue();
446}
447
448static Mips::CondCode condCodeToFCC(ISD::CondCode CC) {
449  switch (CC) {
450  default: llvm_unreachable("Unknown fp condition code!");
451  case ISD::SETEQ:
452  case ISD::SETOEQ: return Mips::FCOND_OEQ;
453  case ISD::SETUNE: return Mips::FCOND_UNE;
454  case ISD::SETLT:
455  case ISD::SETOLT: return Mips::FCOND_OLT;
456  case ISD::SETGT:
457  case ISD::SETOGT: return Mips::FCOND_OGT;
458  case ISD::SETLE:
459  case ISD::SETOLE: return Mips::FCOND_OLE;
460  case ISD::SETGE:
461  case ISD::SETOGE: return Mips::FCOND_OGE;
462  case ISD::SETULT: return Mips::FCOND_ULT;
463  case ISD::SETULE: return Mips::FCOND_ULE;
464  case ISD::SETUGT: return Mips::FCOND_UGT;
465  case ISD::SETUGE: return Mips::FCOND_UGE;
466  case ISD::SETUO:  return Mips::FCOND_UN;
467  case ISD::SETO:   return Mips::FCOND_OR;
468  case ISD::SETNE:
469  case ISD::SETONE: return Mips::FCOND_ONE;
470  case ISD::SETUEQ: return Mips::FCOND_UEQ;
471  }
472}
473
474
475/// This function returns true if the floating point conditional branches and
476/// conditional moves which use condition code CC should be inverted.
477static bool invertFPCondCodeUser(Mips::CondCode CC) {
478  if (CC >= Mips::FCOND_F && CC <= Mips::FCOND_NGT)
479    return false;
480
481  assert((CC >= Mips::FCOND_T && CC <= Mips::FCOND_GT) &&
482         "Illegal Condition Code");
483
484  return true;
485}
486
487// Creates and returns an FPCmp node from a setcc node.
488// Returns Op if setcc is not a floating point comparison.
489static SDValue createFPCmp(SelectionDAG &DAG, const SDValue &Op) {
490  // must be a SETCC node
491  if (Op.getOpcode() != ISD::SETCC)
492    return Op;
493
494  SDValue LHS = Op.getOperand(0);
495
496  if (!LHS.getValueType().isFloatingPoint())
497    return Op;
498
499  SDValue RHS = Op.getOperand(1);
500  DebugLoc DL = Op.getDebugLoc();
501
502  // Assume the 3rd operand is a CondCodeSDNode. Add code to check the type of
503  // node if necessary.
504  ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(2))->get();
505
506  return DAG.getNode(MipsISD::FPCmp, DL, MVT::Glue, LHS, RHS,
507                     DAG.getConstant(condCodeToFCC(CC), MVT::i32));
508}
509
510// Creates and returns a CMovFPT/F node.
511static SDValue createCMovFP(SelectionDAG &DAG, SDValue Cond, SDValue True,
512                            SDValue False, DebugLoc DL) {
513  ConstantSDNode *CC = cast<ConstantSDNode>(Cond.getOperand(2));
514  bool invert = invertFPCondCodeUser((Mips::CondCode)CC->getSExtValue());
515
516  return DAG.getNode((invert ? MipsISD::CMovFP_F : MipsISD::CMovFP_T), DL,
517                     True.getValueType(), True, False, Cond);
518}
519
520static SDValue performSELECTCombine(SDNode *N, SelectionDAG &DAG,
521                                    TargetLowering::DAGCombinerInfo &DCI,
522                                    const MipsSubtarget *Subtarget) {
523  if (DCI.isBeforeLegalizeOps())
524    return SDValue();
525
526  SDValue SetCC = N->getOperand(0);
527
528  if ((SetCC.getOpcode() != ISD::SETCC) ||
529      !SetCC.getOperand(0).getValueType().isInteger())
530    return SDValue();
531
532  SDValue False = N->getOperand(2);
533  EVT FalseTy = False.getValueType();
534
535  if (!FalseTy.isInteger())
536    return SDValue();
537
538  ConstantSDNode *CN = dyn_cast<ConstantSDNode>(False);
539
540  if (!CN || CN->getZExtValue())
541    return SDValue();
542
543  const DebugLoc DL = N->getDebugLoc();
544  ISD::CondCode CC = cast<CondCodeSDNode>(SetCC.getOperand(2))->get();
545  SDValue True = N->getOperand(1);
546
547  SetCC = DAG.getSetCC(DL, SetCC.getValueType(), SetCC.getOperand(0),
548                       SetCC.getOperand(1), ISD::getSetCCInverse(CC, true));
549
550  return DAG.getNode(ISD::SELECT, DL, FalseTy, SetCC, False, True);
551}
552
553static SDValue performANDCombine(SDNode *N, SelectionDAG &DAG,
554                                 TargetLowering::DAGCombinerInfo &DCI,
555                                 const MipsSubtarget *Subtarget) {
556  // Pattern match EXT.
557  //  $dst = and ((sra or srl) $src , pos), (2**size - 1)
558  //  => ext $dst, $src, size, pos
559  if (DCI.isBeforeLegalizeOps() || !Subtarget->hasMips32r2())
560    return SDValue();
561
562  SDValue ShiftRight = N->getOperand(0), Mask = N->getOperand(1);
563  unsigned ShiftRightOpc = ShiftRight.getOpcode();
564
565  // Op's first operand must be a shift right.
566  if (ShiftRightOpc != ISD::SRA && ShiftRightOpc != ISD::SRL)
567    return SDValue();
568
569  // The second operand of the shift must be an immediate.
570  ConstantSDNode *CN;
571  if (!(CN = dyn_cast<ConstantSDNode>(ShiftRight.getOperand(1))))
572    return SDValue();
573
574  uint64_t Pos = CN->getZExtValue();
575  uint64_t SMPos, SMSize;
576
577  // Op's second operand must be a shifted mask.
578  if (!(CN = dyn_cast<ConstantSDNode>(Mask)) ||
579      !isShiftedMask(CN->getZExtValue(), SMPos, SMSize))
580    return SDValue();
581
582  // Return if the shifted mask does not start at bit 0 or the sum of its size
583  // and Pos exceeds the word's size.
584  EVT ValTy = N->getValueType(0);
585  if (SMPos != 0 || Pos + SMSize > ValTy.getSizeInBits())
586    return SDValue();
587
588  return DAG.getNode(MipsISD::Ext, N->getDebugLoc(), ValTy,
589                     ShiftRight.getOperand(0), DAG.getConstant(Pos, MVT::i32),
590                     DAG.getConstant(SMSize, MVT::i32));
591}
592
593static SDValue performORCombine(SDNode *N, SelectionDAG &DAG,
594                                TargetLowering::DAGCombinerInfo &DCI,
595                                const MipsSubtarget *Subtarget) {
596  // Pattern match INS.
597  //  $dst = or (and $src1 , mask0), (and (shl $src, pos), mask1),
598  //  where mask1 = (2**size - 1) << pos, mask0 = ~mask1
599  //  => ins $dst, $src, size, pos, $src1
600  if (DCI.isBeforeLegalizeOps() || !Subtarget->hasMips32r2())
601    return SDValue();
602
603  SDValue And0 = N->getOperand(0), And1 = N->getOperand(1);
604  uint64_t SMPos0, SMSize0, SMPos1, SMSize1;
605  ConstantSDNode *CN;
606
607  // See if Op's first operand matches (and $src1 , mask0).
608  if (And0.getOpcode() != ISD::AND)
609    return SDValue();
610
611  if (!(CN = dyn_cast<ConstantSDNode>(And0.getOperand(1))) ||
612      !isShiftedMask(~CN->getSExtValue(), SMPos0, SMSize0))
613    return SDValue();
614
615  // See if Op's second operand matches (and (shl $src, pos), mask1).
616  if (And1.getOpcode() != ISD::AND)
617    return SDValue();
618
619  if (!(CN = dyn_cast<ConstantSDNode>(And1.getOperand(1))) ||
620      !isShiftedMask(CN->getZExtValue(), SMPos1, SMSize1))
621    return SDValue();
622
623  // The shift masks must have the same position and size.
624  if (SMPos0 != SMPos1 || SMSize0 != SMSize1)
625    return SDValue();
626
627  SDValue Shl = And1.getOperand(0);
628  if (Shl.getOpcode() != ISD::SHL)
629    return SDValue();
630
631  if (!(CN = dyn_cast<ConstantSDNode>(Shl.getOperand(1))))
632    return SDValue();
633
634  unsigned Shamt = CN->getZExtValue();
635
636  // Return if the shift amount and the first bit position of mask are not the
637  // same.
638  EVT ValTy = N->getValueType(0);
639  if ((Shamt != SMPos0) || (SMPos0 + SMSize0 > ValTy.getSizeInBits()))
640    return SDValue();
641
642  return DAG.getNode(MipsISD::Ins, N->getDebugLoc(), ValTy, Shl.getOperand(0),
643                     DAG.getConstant(SMPos0, MVT::i32),
644                     DAG.getConstant(SMSize0, MVT::i32), And0.getOperand(0));
645}
646
647static SDValue performADDCombine(SDNode *N, SelectionDAG &DAG,
648                                 TargetLowering::DAGCombinerInfo &DCI,
649                                 const MipsSubtarget *Subtarget) {
650  // (add v0, (add v1, abs_lo(tjt))) => (add (add v0, v1), abs_lo(tjt))
651
652  if (DCI.isBeforeLegalizeOps())
653    return SDValue();
654
655  SDValue Add = N->getOperand(1);
656
657  if (Add.getOpcode() != ISD::ADD)
658    return SDValue();
659
660  SDValue Lo = Add.getOperand(1);
661
662  if ((Lo.getOpcode() != MipsISD::Lo) ||
663      (Lo.getOperand(0).getOpcode() != ISD::TargetJumpTable))
664    return SDValue();
665
666  EVT ValTy = N->getValueType(0);
667  DebugLoc DL = N->getDebugLoc();
668
669  SDValue Add1 = DAG.getNode(ISD::ADD, DL, ValTy, N->getOperand(0),
670                             Add.getOperand(0));
671  return DAG.getNode(ISD::ADD, DL, ValTy, Add1, Lo);
672}
673
674SDValue  MipsTargetLowering::PerformDAGCombine(SDNode *N, DAGCombinerInfo &DCI)
675  const {
676  SelectionDAG &DAG = DCI.DAG;
677  unsigned Opc = N->getOpcode();
678
679  switch (Opc) {
680  default: break;
681  case ISD::SDIVREM:
682  case ISD::UDIVREM:
683    return performDivRemCombine(N, DAG, DCI, Subtarget);
684  case ISD::SELECT:
685    return performSELECTCombine(N, DAG, DCI, Subtarget);
686  case ISD::AND:
687    return performANDCombine(N, DAG, DCI, Subtarget);
688  case ISD::OR:
689    return performORCombine(N, DAG, DCI, Subtarget);
690  case ISD::ADD:
691    return performADDCombine(N, DAG, DCI, Subtarget);
692  }
693
694  return SDValue();
695}
696
697void
698MipsTargetLowering::LowerOperationWrapper(SDNode *N,
699                                          SmallVectorImpl<SDValue> &Results,
700                                          SelectionDAG &DAG) const {
701  SDValue Res = LowerOperation(SDValue(N, 0), DAG);
702
703  for (unsigned I = 0, E = Res->getNumValues(); I != E; ++I)
704    Results.push_back(Res.getValue(I));
705}
706
707void
708MipsTargetLowering::ReplaceNodeResults(SDNode *N,
709                                       SmallVectorImpl<SDValue> &Results,
710                                       SelectionDAG &DAG) const {
711  SDValue Res = LowerOperation(SDValue(N, 0), DAG);
712
713  for (unsigned I = 0, E = Res->getNumValues(); I != E; ++I)
714    Results.push_back(Res.getValue(I));
715}
716
717SDValue MipsTargetLowering::
718LowerOperation(SDValue Op, SelectionDAG &DAG) const
719{
720  switch (Op.getOpcode())
721  {
722  case ISD::BR_JT:              return lowerBR_JT(Op, DAG);
723  case ISD::BRCOND:             return lowerBRCOND(Op, DAG);
724  case ISD::ConstantPool:       return lowerConstantPool(Op, DAG);
725  case ISD::GlobalAddress:      return lowerGlobalAddress(Op, DAG);
726  case ISD::BlockAddress:       return lowerBlockAddress(Op, DAG);
727  case ISD::GlobalTLSAddress:   return lowerGlobalTLSAddress(Op, DAG);
728  case ISD::JumpTable:          return lowerJumpTable(Op, DAG);
729  case ISD::SELECT:             return lowerSELECT(Op, DAG);
730  case ISD::SELECT_CC:          return lowerSELECT_CC(Op, DAG);
731  case ISD::SETCC:              return lowerSETCC(Op, DAG);
732  case ISD::VASTART:            return lowerVASTART(Op, DAG);
733  case ISD::FCOPYSIGN:          return lowerFCOPYSIGN(Op, DAG);
734  case ISD::FABS:               return lowerFABS(Op, DAG);
735  case ISD::FRAMEADDR:          return lowerFRAMEADDR(Op, DAG);
736  case ISD::RETURNADDR:         return lowerRETURNADDR(Op, DAG);
737  case ISD::EH_RETURN:          return lowerEH_RETURN(Op, DAG);
738  case ISD::MEMBARRIER:         return lowerMEMBARRIER(Op, DAG);
739  case ISD::ATOMIC_FENCE:       return lowerATOMIC_FENCE(Op, DAG);
740  case ISD::SHL_PARTS:          return lowerShiftLeftParts(Op, DAG);
741  case ISD::SRA_PARTS:          return lowerShiftRightParts(Op, DAG, true);
742  case ISD::SRL_PARTS:          return lowerShiftRightParts(Op, DAG, false);
743  case ISD::LOAD:               return lowerLOAD(Op, DAG);
744  case ISD::STORE:              return lowerSTORE(Op, DAG);
745  case ISD::ADD:                return lowerADD(Op, DAG);
746  }
747  return SDValue();
748}
749
750//===----------------------------------------------------------------------===//
751//  Lower helper functions
752//===----------------------------------------------------------------------===//
753
754// addLiveIn - This helper function adds the specified physical register to the
755// MachineFunction as a live in value.  It also creates a corresponding
756// virtual register for it.
757static unsigned
758addLiveIn(MachineFunction &MF, unsigned PReg, const TargetRegisterClass *RC)
759{
760  unsigned VReg = MF.getRegInfo().createVirtualRegister(RC);
761  MF.getRegInfo().addLiveIn(PReg, VReg);
762  return VReg;
763}
764
765MachineBasicBlock *
766MipsTargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
767                                                MachineBasicBlock *BB) const {
768  switch (MI->getOpcode()) {
769  default:
770    llvm_unreachable("Unexpected instr type to insert");
771  case Mips::ATOMIC_LOAD_ADD_I8:
772  case Mips::ATOMIC_LOAD_ADD_I8_P8:
773    return emitAtomicBinaryPartword(MI, BB, 1, Mips::ADDu);
774  case Mips::ATOMIC_LOAD_ADD_I16:
775  case Mips::ATOMIC_LOAD_ADD_I16_P8:
776    return emitAtomicBinaryPartword(MI, BB, 2, Mips::ADDu);
777  case Mips::ATOMIC_LOAD_ADD_I32:
778  case Mips::ATOMIC_LOAD_ADD_I32_P8:
779    return emitAtomicBinary(MI, BB, 4, Mips::ADDu);
780  case Mips::ATOMIC_LOAD_ADD_I64:
781  case Mips::ATOMIC_LOAD_ADD_I64_P8:
782    return emitAtomicBinary(MI, BB, 8, Mips::DADDu);
783
784  case Mips::ATOMIC_LOAD_AND_I8:
785  case Mips::ATOMIC_LOAD_AND_I8_P8:
786    return emitAtomicBinaryPartword(MI, BB, 1, Mips::AND);
787  case Mips::ATOMIC_LOAD_AND_I16:
788  case Mips::ATOMIC_LOAD_AND_I16_P8:
789    return emitAtomicBinaryPartword(MI, BB, 2, Mips::AND);
790  case Mips::ATOMIC_LOAD_AND_I32:
791  case Mips::ATOMIC_LOAD_AND_I32_P8:
792    return emitAtomicBinary(MI, BB, 4, Mips::AND);
793  case Mips::ATOMIC_LOAD_AND_I64:
794  case Mips::ATOMIC_LOAD_AND_I64_P8:
795    return emitAtomicBinary(MI, BB, 8, Mips::AND64);
796
797  case Mips::ATOMIC_LOAD_OR_I8:
798  case Mips::ATOMIC_LOAD_OR_I8_P8:
799    return emitAtomicBinaryPartword(MI, BB, 1, Mips::OR);
800  case Mips::ATOMIC_LOAD_OR_I16:
801  case Mips::ATOMIC_LOAD_OR_I16_P8:
802    return emitAtomicBinaryPartword(MI, BB, 2, Mips::OR);
803  case Mips::ATOMIC_LOAD_OR_I32:
804  case Mips::ATOMIC_LOAD_OR_I32_P8:
805    return emitAtomicBinary(MI, BB, 4, Mips::OR);
806  case Mips::ATOMIC_LOAD_OR_I64:
807  case Mips::ATOMIC_LOAD_OR_I64_P8:
808    return emitAtomicBinary(MI, BB, 8, Mips::OR64);
809
810  case Mips::ATOMIC_LOAD_XOR_I8:
811  case Mips::ATOMIC_LOAD_XOR_I8_P8:
812    return emitAtomicBinaryPartword(MI, BB, 1, Mips::XOR);
813  case Mips::ATOMIC_LOAD_XOR_I16:
814  case Mips::ATOMIC_LOAD_XOR_I16_P8:
815    return emitAtomicBinaryPartword(MI, BB, 2, Mips::XOR);
816  case Mips::ATOMIC_LOAD_XOR_I32:
817  case Mips::ATOMIC_LOAD_XOR_I32_P8:
818    return emitAtomicBinary(MI, BB, 4, Mips::XOR);
819  case Mips::ATOMIC_LOAD_XOR_I64:
820  case Mips::ATOMIC_LOAD_XOR_I64_P8:
821    return emitAtomicBinary(MI, BB, 8, Mips::XOR64);
822
823  case Mips::ATOMIC_LOAD_NAND_I8:
824  case Mips::ATOMIC_LOAD_NAND_I8_P8:
825    return emitAtomicBinaryPartword(MI, BB, 1, 0, true);
826  case Mips::ATOMIC_LOAD_NAND_I16:
827  case Mips::ATOMIC_LOAD_NAND_I16_P8:
828    return emitAtomicBinaryPartword(MI, BB, 2, 0, true);
829  case Mips::ATOMIC_LOAD_NAND_I32:
830  case Mips::ATOMIC_LOAD_NAND_I32_P8:
831    return emitAtomicBinary(MI, BB, 4, 0, true);
832  case Mips::ATOMIC_LOAD_NAND_I64:
833  case Mips::ATOMIC_LOAD_NAND_I64_P8:
834    return emitAtomicBinary(MI, BB, 8, 0, true);
835
836  case Mips::ATOMIC_LOAD_SUB_I8:
837  case Mips::ATOMIC_LOAD_SUB_I8_P8:
838    return emitAtomicBinaryPartword(MI, BB, 1, Mips::SUBu);
839  case Mips::ATOMIC_LOAD_SUB_I16:
840  case Mips::ATOMIC_LOAD_SUB_I16_P8:
841    return emitAtomicBinaryPartword(MI, BB, 2, Mips::SUBu);
842  case Mips::ATOMIC_LOAD_SUB_I32:
843  case Mips::ATOMIC_LOAD_SUB_I32_P8:
844    return emitAtomicBinary(MI, BB, 4, Mips::SUBu);
845  case Mips::ATOMIC_LOAD_SUB_I64:
846  case Mips::ATOMIC_LOAD_SUB_I64_P8:
847    return emitAtomicBinary(MI, BB, 8, Mips::DSUBu);
848
849  case Mips::ATOMIC_SWAP_I8:
850  case Mips::ATOMIC_SWAP_I8_P8:
851    return emitAtomicBinaryPartword(MI, BB, 1, 0);
852  case Mips::ATOMIC_SWAP_I16:
853  case Mips::ATOMIC_SWAP_I16_P8:
854    return emitAtomicBinaryPartword(MI, BB, 2, 0);
855  case Mips::ATOMIC_SWAP_I32:
856  case Mips::ATOMIC_SWAP_I32_P8:
857    return emitAtomicBinary(MI, BB, 4, 0);
858  case Mips::ATOMIC_SWAP_I64:
859  case Mips::ATOMIC_SWAP_I64_P8:
860    return emitAtomicBinary(MI, BB, 8, 0);
861
862  case Mips::ATOMIC_CMP_SWAP_I8:
863  case Mips::ATOMIC_CMP_SWAP_I8_P8:
864    return emitAtomicCmpSwapPartword(MI, BB, 1);
865  case Mips::ATOMIC_CMP_SWAP_I16:
866  case Mips::ATOMIC_CMP_SWAP_I16_P8:
867    return emitAtomicCmpSwapPartword(MI, BB, 2);
868  case Mips::ATOMIC_CMP_SWAP_I32:
869  case Mips::ATOMIC_CMP_SWAP_I32_P8:
870    return emitAtomicCmpSwap(MI, BB, 4);
871  case Mips::ATOMIC_CMP_SWAP_I64:
872  case Mips::ATOMIC_CMP_SWAP_I64_P8:
873    return emitAtomicCmpSwap(MI, BB, 8);
874  }
875}
876
877// This function also handles Mips::ATOMIC_SWAP_I32 (when BinOpcode == 0), and
878// Mips::ATOMIC_LOAD_NAND_I32 (when Nand == true)
879MachineBasicBlock *
880MipsTargetLowering::emitAtomicBinary(MachineInstr *MI, MachineBasicBlock *BB,
881                                     unsigned Size, unsigned BinOpcode,
882                                     bool Nand) const {
883  assert((Size == 4 || Size == 8) && "Unsupported size for EmitAtomicBinary.");
884
885  MachineFunction *MF = BB->getParent();
886  MachineRegisterInfo &RegInfo = MF->getRegInfo();
887  const TargetRegisterClass *RC = getRegClassFor(MVT::getIntegerVT(Size * 8));
888  const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
889  DebugLoc DL = MI->getDebugLoc();
890  unsigned LL, SC, AND, NOR, ZERO, BEQ;
891
892  if (Size == 4) {
893    LL = IsN64 ? Mips::LL_P8 : Mips::LL;
894    SC = IsN64 ? Mips::SC_P8 : Mips::SC;
895    AND = Mips::AND;
896    NOR = Mips::NOR;
897    ZERO = Mips::ZERO;
898    BEQ = Mips::BEQ;
899  }
900  else {
901    LL = IsN64 ? Mips::LLD_P8 : Mips::LLD;
902    SC = IsN64 ? Mips::SCD_P8 : Mips::SCD;
903    AND = Mips::AND64;
904    NOR = Mips::NOR64;
905    ZERO = Mips::ZERO_64;
906    BEQ = Mips::BEQ64;
907  }
908
909  unsigned OldVal = MI->getOperand(0).getReg();
910  unsigned Ptr = MI->getOperand(1).getReg();
911  unsigned Incr = MI->getOperand(2).getReg();
912
913  unsigned StoreVal = RegInfo.createVirtualRegister(RC);
914  unsigned AndRes = RegInfo.createVirtualRegister(RC);
915  unsigned Success = RegInfo.createVirtualRegister(RC);
916
917  // insert new blocks after the current block
918  const BasicBlock *LLVM_BB = BB->getBasicBlock();
919  MachineBasicBlock *loopMBB = MF->CreateMachineBasicBlock(LLVM_BB);
920  MachineBasicBlock *exitMBB = MF->CreateMachineBasicBlock(LLVM_BB);
921  MachineFunction::iterator It = BB;
922  ++It;
923  MF->insert(It, loopMBB);
924  MF->insert(It, exitMBB);
925
926  // Transfer the remainder of BB and its successor edges to exitMBB.
927  exitMBB->splice(exitMBB->begin(), BB,
928                  llvm::next(MachineBasicBlock::iterator(MI)),
929                  BB->end());
930  exitMBB->transferSuccessorsAndUpdatePHIs(BB);
931
932  //  thisMBB:
933  //    ...
934  //    fallthrough --> loopMBB
935  BB->addSuccessor(loopMBB);
936  loopMBB->addSuccessor(loopMBB);
937  loopMBB->addSuccessor(exitMBB);
938
939  //  loopMBB:
940  //    ll oldval, 0(ptr)
941  //    <binop> storeval, oldval, incr
942  //    sc success, storeval, 0(ptr)
943  //    beq success, $0, loopMBB
944  BB = loopMBB;
945  BuildMI(BB, DL, TII->get(LL), OldVal).addReg(Ptr).addImm(0);
946  if (Nand) {
947    //  and andres, oldval, incr
948    //  nor storeval, $0, andres
949    BuildMI(BB, DL, TII->get(AND), AndRes).addReg(OldVal).addReg(Incr);
950    BuildMI(BB, DL, TII->get(NOR), StoreVal).addReg(ZERO).addReg(AndRes);
951  } else if (BinOpcode) {
952    //  <binop> storeval, oldval, incr
953    BuildMI(BB, DL, TII->get(BinOpcode), StoreVal).addReg(OldVal).addReg(Incr);
954  } else {
955    StoreVal = Incr;
956  }
957  BuildMI(BB, DL, TII->get(SC), Success).addReg(StoreVal).addReg(Ptr).addImm(0);
958  BuildMI(BB, DL, TII->get(BEQ)).addReg(Success).addReg(ZERO).addMBB(loopMBB);
959
960  MI->eraseFromParent();   // The instruction is gone now.
961
962  return exitMBB;
963}
964
965MachineBasicBlock *
966MipsTargetLowering::emitAtomicBinaryPartword(MachineInstr *MI,
967                                             MachineBasicBlock *BB,
968                                             unsigned Size, unsigned BinOpcode,
969                                             bool Nand) const {
970  assert((Size == 1 || Size == 2) &&
971      "Unsupported size for EmitAtomicBinaryPartial.");
972
973  MachineFunction *MF = BB->getParent();
974  MachineRegisterInfo &RegInfo = MF->getRegInfo();
975  const TargetRegisterClass *RC = getRegClassFor(MVT::i32);
976  const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
977  DebugLoc DL = MI->getDebugLoc();
978  unsigned LL = IsN64 ? Mips::LL_P8 : Mips::LL;
979  unsigned SC = IsN64 ? Mips::SC_P8 : Mips::SC;
980
981  unsigned Dest = MI->getOperand(0).getReg();
982  unsigned Ptr = MI->getOperand(1).getReg();
983  unsigned Incr = MI->getOperand(2).getReg();
984
985  unsigned AlignedAddr = RegInfo.createVirtualRegister(RC);
986  unsigned ShiftAmt = RegInfo.createVirtualRegister(RC);
987  unsigned Mask = RegInfo.createVirtualRegister(RC);
988  unsigned Mask2 = RegInfo.createVirtualRegister(RC);
989  unsigned NewVal = RegInfo.createVirtualRegister(RC);
990  unsigned OldVal = RegInfo.createVirtualRegister(RC);
991  unsigned Incr2 = RegInfo.createVirtualRegister(RC);
992  unsigned MaskLSB2 = RegInfo.createVirtualRegister(RC);
993  unsigned PtrLSB2 = RegInfo.createVirtualRegister(RC);
994  unsigned MaskUpper = RegInfo.createVirtualRegister(RC);
995  unsigned AndRes = RegInfo.createVirtualRegister(RC);
996  unsigned BinOpRes = RegInfo.createVirtualRegister(RC);
997  unsigned MaskedOldVal0 = RegInfo.createVirtualRegister(RC);
998  unsigned StoreVal = RegInfo.createVirtualRegister(RC);
999  unsigned MaskedOldVal1 = RegInfo.createVirtualRegister(RC);
1000  unsigned SrlRes = RegInfo.createVirtualRegister(RC);
1001  unsigned SllRes = RegInfo.createVirtualRegister(RC);
1002  unsigned Success = RegInfo.createVirtualRegister(RC);
1003
1004  // insert new blocks after the current block
1005  const BasicBlock *LLVM_BB = BB->getBasicBlock();
1006  MachineBasicBlock *loopMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1007  MachineBasicBlock *sinkMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1008  MachineBasicBlock *exitMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1009  MachineFunction::iterator It = BB;
1010  ++It;
1011  MF->insert(It, loopMBB);
1012  MF->insert(It, sinkMBB);
1013  MF->insert(It, exitMBB);
1014
1015  // Transfer the remainder of BB and its successor edges to exitMBB.
1016  exitMBB->splice(exitMBB->begin(), BB,
1017                  llvm::next(MachineBasicBlock::iterator(MI)), BB->end());
1018  exitMBB->transferSuccessorsAndUpdatePHIs(BB);
1019
1020  BB->addSuccessor(loopMBB);
1021  loopMBB->addSuccessor(loopMBB);
1022  loopMBB->addSuccessor(sinkMBB);
1023  sinkMBB->addSuccessor(exitMBB);
1024
1025  //  thisMBB:
1026  //    addiu   masklsb2,$0,-4                # 0xfffffffc
1027  //    and     alignedaddr,ptr,masklsb2
1028  //    andi    ptrlsb2,ptr,3
1029  //    sll     shiftamt,ptrlsb2,3
1030  //    ori     maskupper,$0,255               # 0xff
1031  //    sll     mask,maskupper,shiftamt
1032  //    nor     mask2,$0,mask
1033  //    sll     incr2,incr,shiftamt
1034
1035  int64_t MaskImm = (Size == 1) ? 255 : 65535;
1036  BuildMI(BB, DL, TII->get(Mips::ADDiu), MaskLSB2)
1037    .addReg(Mips::ZERO).addImm(-4);
1038  BuildMI(BB, DL, TII->get(Mips::AND), AlignedAddr)
1039    .addReg(Ptr).addReg(MaskLSB2);
1040  BuildMI(BB, DL, TII->get(Mips::ANDi), PtrLSB2).addReg(Ptr).addImm(3);
1041  BuildMI(BB, DL, TII->get(Mips::SLL), ShiftAmt).addReg(PtrLSB2).addImm(3);
1042  BuildMI(BB, DL, TII->get(Mips::ORi), MaskUpper)
1043    .addReg(Mips::ZERO).addImm(MaskImm);
1044  BuildMI(BB, DL, TII->get(Mips::SLLV), Mask)
1045    .addReg(ShiftAmt).addReg(MaskUpper);
1046  BuildMI(BB, DL, TII->get(Mips::NOR), Mask2).addReg(Mips::ZERO).addReg(Mask);
1047  BuildMI(BB, DL, TII->get(Mips::SLLV), Incr2).addReg(ShiftAmt).addReg(Incr);
1048
1049  // atomic.load.binop
1050  // loopMBB:
1051  //   ll      oldval,0(alignedaddr)
1052  //   binop   binopres,oldval,incr2
1053  //   and     newval,binopres,mask
1054  //   and     maskedoldval0,oldval,mask2
1055  //   or      storeval,maskedoldval0,newval
1056  //   sc      success,storeval,0(alignedaddr)
1057  //   beq     success,$0,loopMBB
1058
1059  // atomic.swap
1060  // loopMBB:
1061  //   ll      oldval,0(alignedaddr)
1062  //   and     newval,incr2,mask
1063  //   and     maskedoldval0,oldval,mask2
1064  //   or      storeval,maskedoldval0,newval
1065  //   sc      success,storeval,0(alignedaddr)
1066  //   beq     success,$0,loopMBB
1067
1068  BB = loopMBB;
1069  BuildMI(BB, DL, TII->get(LL), OldVal).addReg(AlignedAddr).addImm(0);
1070  if (Nand) {
1071    //  and andres, oldval, incr2
1072    //  nor binopres, $0, andres
1073    //  and newval, binopres, mask
1074    BuildMI(BB, DL, TII->get(Mips::AND), AndRes).addReg(OldVal).addReg(Incr2);
1075    BuildMI(BB, DL, TII->get(Mips::NOR), BinOpRes)
1076      .addReg(Mips::ZERO).addReg(AndRes);
1077    BuildMI(BB, DL, TII->get(Mips::AND), NewVal).addReg(BinOpRes).addReg(Mask);
1078  } else if (BinOpcode) {
1079    //  <binop> binopres, oldval, incr2
1080    //  and newval, binopres, mask
1081    BuildMI(BB, DL, TII->get(BinOpcode), BinOpRes).addReg(OldVal).addReg(Incr2);
1082    BuildMI(BB, DL, TII->get(Mips::AND), NewVal).addReg(BinOpRes).addReg(Mask);
1083  } else {// atomic.swap
1084    //  and newval, incr2, mask
1085    BuildMI(BB, DL, TII->get(Mips::AND), NewVal).addReg(Incr2).addReg(Mask);
1086  }
1087
1088  BuildMI(BB, DL, TII->get(Mips::AND), MaskedOldVal0)
1089    .addReg(OldVal).addReg(Mask2);
1090  BuildMI(BB, DL, TII->get(Mips::OR), StoreVal)
1091    .addReg(MaskedOldVal0).addReg(NewVal);
1092  BuildMI(BB, DL, TII->get(SC), Success)
1093    .addReg(StoreVal).addReg(AlignedAddr).addImm(0);
1094  BuildMI(BB, DL, TII->get(Mips::BEQ))
1095    .addReg(Success).addReg(Mips::ZERO).addMBB(loopMBB);
1096
1097  //  sinkMBB:
1098  //    and     maskedoldval1,oldval,mask
1099  //    srl     srlres,maskedoldval1,shiftamt
1100  //    sll     sllres,srlres,24
1101  //    sra     dest,sllres,24
1102  BB = sinkMBB;
1103  int64_t ShiftImm = (Size == 1) ? 24 : 16;
1104
1105  BuildMI(BB, DL, TII->get(Mips::AND), MaskedOldVal1)
1106    .addReg(OldVal).addReg(Mask);
1107  BuildMI(BB, DL, TII->get(Mips::SRLV), SrlRes)
1108      .addReg(ShiftAmt).addReg(MaskedOldVal1);
1109  BuildMI(BB, DL, TII->get(Mips::SLL), SllRes)
1110      .addReg(SrlRes).addImm(ShiftImm);
1111  BuildMI(BB, DL, TII->get(Mips::SRA), Dest)
1112      .addReg(SllRes).addImm(ShiftImm);
1113
1114  MI->eraseFromParent();   // The instruction is gone now.
1115
1116  return exitMBB;
1117}
1118
1119MachineBasicBlock *
1120MipsTargetLowering::emitAtomicCmpSwap(MachineInstr *MI,
1121                                      MachineBasicBlock *BB,
1122                                      unsigned Size) const {
1123  assert((Size == 4 || Size == 8) && "Unsupported size for EmitAtomicCmpSwap.");
1124
1125  MachineFunction *MF = BB->getParent();
1126  MachineRegisterInfo &RegInfo = MF->getRegInfo();
1127  const TargetRegisterClass *RC = getRegClassFor(MVT::getIntegerVT(Size * 8));
1128  const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
1129  DebugLoc DL = MI->getDebugLoc();
1130  unsigned LL, SC, ZERO, BNE, BEQ;
1131
1132  if (Size == 4) {
1133    LL = IsN64 ? Mips::LL_P8 : Mips::LL;
1134    SC = IsN64 ? Mips::SC_P8 : Mips::SC;
1135    ZERO = Mips::ZERO;
1136    BNE = Mips::BNE;
1137    BEQ = Mips::BEQ;
1138  }
1139  else {
1140    LL = IsN64 ? Mips::LLD_P8 : Mips::LLD;
1141    SC = IsN64 ? Mips::SCD_P8 : Mips::SCD;
1142    ZERO = Mips::ZERO_64;
1143    BNE = Mips::BNE64;
1144    BEQ = Mips::BEQ64;
1145  }
1146
1147  unsigned Dest    = MI->getOperand(0).getReg();
1148  unsigned Ptr     = MI->getOperand(1).getReg();
1149  unsigned OldVal  = MI->getOperand(2).getReg();
1150  unsigned NewVal  = MI->getOperand(3).getReg();
1151
1152  unsigned Success = RegInfo.createVirtualRegister(RC);
1153
1154  // insert new blocks after the current block
1155  const BasicBlock *LLVM_BB = BB->getBasicBlock();
1156  MachineBasicBlock *loop1MBB = MF->CreateMachineBasicBlock(LLVM_BB);
1157  MachineBasicBlock *loop2MBB = MF->CreateMachineBasicBlock(LLVM_BB);
1158  MachineBasicBlock *exitMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1159  MachineFunction::iterator It = BB;
1160  ++It;
1161  MF->insert(It, loop1MBB);
1162  MF->insert(It, loop2MBB);
1163  MF->insert(It, exitMBB);
1164
1165  // Transfer the remainder of BB and its successor edges to exitMBB.
1166  exitMBB->splice(exitMBB->begin(), BB,
1167                  llvm::next(MachineBasicBlock::iterator(MI)), BB->end());
1168  exitMBB->transferSuccessorsAndUpdatePHIs(BB);
1169
1170  //  thisMBB:
1171  //    ...
1172  //    fallthrough --> loop1MBB
1173  BB->addSuccessor(loop1MBB);
1174  loop1MBB->addSuccessor(exitMBB);
1175  loop1MBB->addSuccessor(loop2MBB);
1176  loop2MBB->addSuccessor(loop1MBB);
1177  loop2MBB->addSuccessor(exitMBB);
1178
1179  // loop1MBB:
1180  //   ll dest, 0(ptr)
1181  //   bne dest, oldval, exitMBB
1182  BB = loop1MBB;
1183  BuildMI(BB, DL, TII->get(LL), Dest).addReg(Ptr).addImm(0);
1184  BuildMI(BB, DL, TII->get(BNE))
1185    .addReg(Dest).addReg(OldVal).addMBB(exitMBB);
1186
1187  // loop2MBB:
1188  //   sc success, newval, 0(ptr)
1189  //   beq success, $0, loop1MBB
1190  BB = loop2MBB;
1191  BuildMI(BB, DL, TII->get(SC), Success)
1192    .addReg(NewVal).addReg(Ptr).addImm(0);
1193  BuildMI(BB, DL, TII->get(BEQ))
1194    .addReg(Success).addReg(ZERO).addMBB(loop1MBB);
1195
1196  MI->eraseFromParent();   // The instruction is gone now.
1197
1198  return exitMBB;
1199}
1200
1201MachineBasicBlock *
1202MipsTargetLowering::emitAtomicCmpSwapPartword(MachineInstr *MI,
1203                                              MachineBasicBlock *BB,
1204                                              unsigned Size) const {
1205  assert((Size == 1 || Size == 2) &&
1206      "Unsupported size for EmitAtomicCmpSwapPartial.");
1207
1208  MachineFunction *MF = BB->getParent();
1209  MachineRegisterInfo &RegInfo = MF->getRegInfo();
1210  const TargetRegisterClass *RC = getRegClassFor(MVT::i32);
1211  const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
1212  DebugLoc DL = MI->getDebugLoc();
1213  unsigned LL = IsN64 ? Mips::LL_P8 : Mips::LL;
1214  unsigned SC = IsN64 ? Mips::SC_P8 : Mips::SC;
1215
1216  unsigned Dest    = MI->getOperand(0).getReg();
1217  unsigned Ptr     = MI->getOperand(1).getReg();
1218  unsigned CmpVal  = MI->getOperand(2).getReg();
1219  unsigned NewVal  = MI->getOperand(3).getReg();
1220
1221  unsigned AlignedAddr = RegInfo.createVirtualRegister(RC);
1222  unsigned ShiftAmt = RegInfo.createVirtualRegister(RC);
1223  unsigned Mask = RegInfo.createVirtualRegister(RC);
1224  unsigned Mask2 = RegInfo.createVirtualRegister(RC);
1225  unsigned ShiftedCmpVal = RegInfo.createVirtualRegister(RC);
1226  unsigned OldVal = RegInfo.createVirtualRegister(RC);
1227  unsigned MaskedOldVal0 = RegInfo.createVirtualRegister(RC);
1228  unsigned ShiftedNewVal = RegInfo.createVirtualRegister(RC);
1229  unsigned MaskLSB2 = RegInfo.createVirtualRegister(RC);
1230  unsigned PtrLSB2 = RegInfo.createVirtualRegister(RC);
1231  unsigned MaskUpper = RegInfo.createVirtualRegister(RC);
1232  unsigned MaskedCmpVal = RegInfo.createVirtualRegister(RC);
1233  unsigned MaskedNewVal = RegInfo.createVirtualRegister(RC);
1234  unsigned MaskedOldVal1 = RegInfo.createVirtualRegister(RC);
1235  unsigned StoreVal = RegInfo.createVirtualRegister(RC);
1236  unsigned SrlRes = RegInfo.createVirtualRegister(RC);
1237  unsigned SllRes = RegInfo.createVirtualRegister(RC);
1238  unsigned Success = RegInfo.createVirtualRegister(RC);
1239
1240  // insert new blocks after the current block
1241  const BasicBlock *LLVM_BB = BB->getBasicBlock();
1242  MachineBasicBlock *loop1MBB = MF->CreateMachineBasicBlock(LLVM_BB);
1243  MachineBasicBlock *loop2MBB = MF->CreateMachineBasicBlock(LLVM_BB);
1244  MachineBasicBlock *sinkMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1245  MachineBasicBlock *exitMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1246  MachineFunction::iterator It = BB;
1247  ++It;
1248  MF->insert(It, loop1MBB);
1249  MF->insert(It, loop2MBB);
1250  MF->insert(It, sinkMBB);
1251  MF->insert(It, exitMBB);
1252
1253  // Transfer the remainder of BB and its successor edges to exitMBB.
1254  exitMBB->splice(exitMBB->begin(), BB,
1255                  llvm::next(MachineBasicBlock::iterator(MI)), BB->end());
1256  exitMBB->transferSuccessorsAndUpdatePHIs(BB);
1257
1258  BB->addSuccessor(loop1MBB);
1259  loop1MBB->addSuccessor(sinkMBB);
1260  loop1MBB->addSuccessor(loop2MBB);
1261  loop2MBB->addSuccessor(loop1MBB);
1262  loop2MBB->addSuccessor(sinkMBB);
1263  sinkMBB->addSuccessor(exitMBB);
1264
1265  // FIXME: computation of newval2 can be moved to loop2MBB.
1266  //  thisMBB:
1267  //    addiu   masklsb2,$0,-4                # 0xfffffffc
1268  //    and     alignedaddr,ptr,masklsb2
1269  //    andi    ptrlsb2,ptr,3
1270  //    sll     shiftamt,ptrlsb2,3
1271  //    ori     maskupper,$0,255               # 0xff
1272  //    sll     mask,maskupper,shiftamt
1273  //    nor     mask2,$0,mask
1274  //    andi    maskedcmpval,cmpval,255
1275  //    sll     shiftedcmpval,maskedcmpval,shiftamt
1276  //    andi    maskednewval,newval,255
1277  //    sll     shiftednewval,maskednewval,shiftamt
1278  int64_t MaskImm = (Size == 1) ? 255 : 65535;
1279  BuildMI(BB, DL, TII->get(Mips::ADDiu), MaskLSB2)
1280    .addReg(Mips::ZERO).addImm(-4);
1281  BuildMI(BB, DL, TII->get(Mips::AND), AlignedAddr)
1282    .addReg(Ptr).addReg(MaskLSB2);
1283  BuildMI(BB, DL, TII->get(Mips::ANDi), PtrLSB2).addReg(Ptr).addImm(3);
1284  BuildMI(BB, DL, TII->get(Mips::SLL), ShiftAmt).addReg(PtrLSB2).addImm(3);
1285  BuildMI(BB, DL, TII->get(Mips::ORi), MaskUpper)
1286    .addReg(Mips::ZERO).addImm(MaskImm);
1287  BuildMI(BB, DL, TII->get(Mips::SLLV), Mask)
1288    .addReg(ShiftAmt).addReg(MaskUpper);
1289  BuildMI(BB, DL, TII->get(Mips::NOR), Mask2).addReg(Mips::ZERO).addReg(Mask);
1290  BuildMI(BB, DL, TII->get(Mips::ANDi), MaskedCmpVal)
1291    .addReg(CmpVal).addImm(MaskImm);
1292  BuildMI(BB, DL, TII->get(Mips::SLLV), ShiftedCmpVal)
1293    .addReg(ShiftAmt).addReg(MaskedCmpVal);
1294  BuildMI(BB, DL, TII->get(Mips::ANDi), MaskedNewVal)
1295    .addReg(NewVal).addImm(MaskImm);
1296  BuildMI(BB, DL, TII->get(Mips::SLLV), ShiftedNewVal)
1297    .addReg(ShiftAmt).addReg(MaskedNewVal);
1298
1299  //  loop1MBB:
1300  //    ll      oldval,0(alginedaddr)
1301  //    and     maskedoldval0,oldval,mask
1302  //    bne     maskedoldval0,shiftedcmpval,sinkMBB
1303  BB = loop1MBB;
1304  BuildMI(BB, DL, TII->get(LL), OldVal).addReg(AlignedAddr).addImm(0);
1305  BuildMI(BB, DL, TII->get(Mips::AND), MaskedOldVal0)
1306    .addReg(OldVal).addReg(Mask);
1307  BuildMI(BB, DL, TII->get(Mips::BNE))
1308    .addReg(MaskedOldVal0).addReg(ShiftedCmpVal).addMBB(sinkMBB);
1309
1310  //  loop2MBB:
1311  //    and     maskedoldval1,oldval,mask2
1312  //    or      storeval,maskedoldval1,shiftednewval
1313  //    sc      success,storeval,0(alignedaddr)
1314  //    beq     success,$0,loop1MBB
1315  BB = loop2MBB;
1316  BuildMI(BB, DL, TII->get(Mips::AND), MaskedOldVal1)
1317    .addReg(OldVal).addReg(Mask2);
1318  BuildMI(BB, DL, TII->get(Mips::OR), StoreVal)
1319    .addReg(MaskedOldVal1).addReg(ShiftedNewVal);
1320  BuildMI(BB, DL, TII->get(SC), Success)
1321      .addReg(StoreVal).addReg(AlignedAddr).addImm(0);
1322  BuildMI(BB, DL, TII->get(Mips::BEQ))
1323      .addReg(Success).addReg(Mips::ZERO).addMBB(loop1MBB);
1324
1325  //  sinkMBB:
1326  //    srl     srlres,maskedoldval0,shiftamt
1327  //    sll     sllres,srlres,24
1328  //    sra     dest,sllres,24
1329  BB = sinkMBB;
1330  int64_t ShiftImm = (Size == 1) ? 24 : 16;
1331
1332  BuildMI(BB, DL, TII->get(Mips::SRLV), SrlRes)
1333      .addReg(ShiftAmt).addReg(MaskedOldVal0);
1334  BuildMI(BB, DL, TII->get(Mips::SLL), SllRes)
1335      .addReg(SrlRes).addImm(ShiftImm);
1336  BuildMI(BB, DL, TII->get(Mips::SRA), Dest)
1337      .addReg(SllRes).addImm(ShiftImm);
1338
1339  MI->eraseFromParent();   // The instruction is gone now.
1340
1341  return exitMBB;
1342}
1343
1344//===----------------------------------------------------------------------===//
1345//  Misc Lower Operation implementation
1346//===----------------------------------------------------------------------===//
1347SDValue MipsTargetLowering::lowerBR_JT(SDValue Op, SelectionDAG &DAG) const {
1348  SDValue Chain = Op.getOperand(0);
1349  SDValue Table = Op.getOperand(1);
1350  SDValue Index = Op.getOperand(2);
1351  DebugLoc DL = Op.getDebugLoc();
1352  EVT PTy = getPointerTy();
1353  unsigned EntrySize =
1354    DAG.getMachineFunction().getJumpTableInfo()->getEntrySize(*getDataLayout());
1355
1356  Index = DAG.getNode(ISD::MUL, DL, PTy, Index,
1357                      DAG.getConstant(EntrySize, PTy));
1358  SDValue Addr = DAG.getNode(ISD::ADD, DL, PTy, Index, Table);
1359
1360  EVT MemVT = EVT::getIntegerVT(*DAG.getContext(), EntrySize * 8);
1361  Addr = DAG.getExtLoad(ISD::SEXTLOAD, DL, PTy, Chain, Addr,
1362                        MachinePointerInfo::getJumpTable(), MemVT, false, false,
1363                        0);
1364  Chain = Addr.getValue(1);
1365
1366  if ((getTargetMachine().getRelocationModel() == Reloc::PIC_) || IsN64) {
1367    // For PIC, the sequence is:
1368    // BRIND(load(Jumptable + index) + RelocBase)
1369    // RelocBase can be JumpTable, GOT or some sort of global base.
1370    Addr = DAG.getNode(ISD::ADD, DL, PTy, Addr,
1371                       getPICJumpTableRelocBase(Table, DAG));
1372  }
1373
1374  return DAG.getNode(ISD::BRIND, DL, MVT::Other, Chain, Addr);
1375}
1376
1377SDValue MipsTargetLowering::
1378lowerBRCOND(SDValue Op, SelectionDAG &DAG) const
1379{
1380  // The first operand is the chain, the second is the condition, the third is
1381  // the block to branch to if the condition is true.
1382  SDValue Chain = Op.getOperand(0);
1383  SDValue Dest = Op.getOperand(2);
1384  DebugLoc DL = Op.getDebugLoc();
1385
1386  SDValue CondRes = createFPCmp(DAG, Op.getOperand(1));
1387
1388  // Return if flag is not set by a floating point comparison.
1389  if (CondRes.getOpcode() != MipsISD::FPCmp)
1390    return Op;
1391
1392  SDValue CCNode  = CondRes.getOperand(2);
1393  Mips::CondCode CC =
1394    (Mips::CondCode)cast<ConstantSDNode>(CCNode)->getZExtValue();
1395  unsigned Opc = invertFPCondCodeUser(CC) ? Mips::BRANCH_F : Mips::BRANCH_T;
1396  SDValue BrCode = DAG.getConstant(Opc, MVT::i32);
1397  return DAG.getNode(MipsISD::FPBrcond, DL, Op.getValueType(), Chain, BrCode,
1398                     Dest, CondRes);
1399}
1400
1401SDValue MipsTargetLowering::
1402lowerSELECT(SDValue Op, SelectionDAG &DAG) const
1403{
1404  SDValue Cond = createFPCmp(DAG, Op.getOperand(0));
1405
1406  // Return if flag is not set by a floating point comparison.
1407  if (Cond.getOpcode() != MipsISD::FPCmp)
1408    return Op;
1409
1410  return createCMovFP(DAG, Cond, Op.getOperand(1), Op.getOperand(2),
1411                      Op.getDebugLoc());
1412}
1413
1414SDValue MipsTargetLowering::
1415lowerSELECT_CC(SDValue Op, SelectionDAG &DAG) const
1416{
1417  DebugLoc DL = Op.getDebugLoc();
1418  EVT Ty = Op.getOperand(0).getValueType();
1419  SDValue Cond = DAG.getNode(ISD::SETCC, DL, getSetCCResultType(Ty),
1420                             Op.getOperand(0), Op.getOperand(1),
1421                             Op.getOperand(4));
1422
1423  return DAG.getNode(ISD::SELECT, DL, Op.getValueType(), Cond, Op.getOperand(2),
1424                     Op.getOperand(3));
1425}
1426
1427SDValue MipsTargetLowering::lowerSETCC(SDValue Op, SelectionDAG &DAG) const {
1428  SDValue Cond = createFPCmp(DAG, Op);
1429
1430  assert(Cond.getOpcode() == MipsISD::FPCmp &&
1431         "Floating point operand expected.");
1432
1433  SDValue True  = DAG.getConstant(1, MVT::i32);
1434  SDValue False = DAG.getConstant(0, MVT::i32);
1435
1436  return createCMovFP(DAG, Cond, True, False, Op.getDebugLoc());
1437}
1438
1439SDValue MipsTargetLowering::lowerGlobalAddress(SDValue Op,
1440                                               SelectionDAG &DAG) const {
1441  // FIXME there isn't actually debug info here
1442  DebugLoc DL = Op.getDebugLoc();
1443  const GlobalValue *GV = cast<GlobalAddressSDNode>(Op)->getGlobal();
1444
1445  if (getTargetMachine().getRelocationModel() != Reloc::PIC_ && !IsN64) {
1446    const MipsTargetObjectFile &TLOF =
1447      (const MipsTargetObjectFile&)getObjFileLowering();
1448
1449    // %gp_rel relocation
1450    if (TLOF.IsGlobalInSmallSection(GV, getTargetMachine())) {
1451      SDValue GA = DAG.getTargetGlobalAddress(GV, DL, MVT::i32, 0,
1452                                              MipsII::MO_GPREL);
1453      SDValue GPRelNode = DAG.getNode(MipsISD::GPRel, DL,
1454                                      DAG.getVTList(MVT::i32), &GA, 1);
1455      SDValue GPReg = DAG.getRegister(Mips::GP, MVT::i32);
1456      return DAG.getNode(ISD::ADD, DL, MVT::i32, GPReg, GPRelNode);
1457    }
1458
1459    // %hi/%lo relocation
1460    return getAddrNonPIC(Op, DAG);
1461  }
1462
1463  if (GV->hasInternalLinkage() || (GV->hasLocalLinkage() && !isa<Function>(GV)))
1464    return getAddrLocal(Op, DAG, HasMips64);
1465
1466  if (LargeGOT)
1467    return getAddrGlobalLargeGOT(Op, DAG, MipsII::MO_GOT_HI16,
1468                                 MipsII::MO_GOT_LO16);
1469
1470  return getAddrGlobal(Op, DAG,
1471                       HasMips64 ? MipsII::MO_GOT_DISP : MipsII::MO_GOT16);
1472}
1473
1474SDValue MipsTargetLowering::lowerBlockAddress(SDValue Op,
1475                                              SelectionDAG &DAG) const {
1476  if (getTargetMachine().getRelocationModel() != Reloc::PIC_ && !IsN64)
1477    return getAddrNonPIC(Op, DAG);
1478
1479  return getAddrLocal(Op, DAG, HasMips64);
1480}
1481
1482SDValue MipsTargetLowering::
1483lowerGlobalTLSAddress(SDValue Op, SelectionDAG &DAG) const
1484{
1485  // If the relocation model is PIC, use the General Dynamic TLS Model or
1486  // Local Dynamic TLS model, otherwise use the Initial Exec or
1487  // Local Exec TLS Model.
1488
1489  GlobalAddressSDNode *GA = cast<GlobalAddressSDNode>(Op);
1490  DebugLoc DL = GA->getDebugLoc();
1491  const GlobalValue *GV = GA->getGlobal();
1492  EVT PtrVT = getPointerTy();
1493
1494  TLSModel::Model model = getTargetMachine().getTLSModel(GV);
1495
1496  if (model == TLSModel::GeneralDynamic || model == TLSModel::LocalDynamic) {
1497    // General Dynamic and Local Dynamic TLS Model.
1498    unsigned Flag = (model == TLSModel::LocalDynamic) ? MipsII::MO_TLSLDM
1499                                                      : MipsII::MO_TLSGD;
1500
1501    SDValue TGA = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0, Flag);
1502    SDValue Argument = DAG.getNode(MipsISD::Wrapper, DL, PtrVT,
1503                                   getGlobalReg(DAG, PtrVT), TGA);
1504    unsigned PtrSize = PtrVT.getSizeInBits();
1505    IntegerType *PtrTy = Type::getIntNTy(*DAG.getContext(), PtrSize);
1506
1507    SDValue TlsGetAddr = DAG.getExternalSymbol("__tls_get_addr", PtrVT);
1508
1509    ArgListTy Args;
1510    ArgListEntry Entry;
1511    Entry.Node = Argument;
1512    Entry.Ty = PtrTy;
1513    Args.push_back(Entry);
1514
1515    TargetLowering::CallLoweringInfo CLI(DAG.getEntryNode(), PtrTy,
1516                  false, false, false, false, 0, CallingConv::C,
1517                  /*IsTailCall=*/false, /*doesNotRet=*/false,
1518                  /*isReturnValueUsed=*/true,
1519                  TlsGetAddr, Args, DAG, DL);
1520    std::pair<SDValue, SDValue> CallResult = LowerCallTo(CLI);
1521
1522    SDValue Ret = CallResult.first;
1523
1524    if (model != TLSModel::LocalDynamic)
1525      return Ret;
1526
1527    SDValue TGAHi = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0,
1528                                               MipsII::MO_DTPREL_HI);
1529    SDValue Hi = DAG.getNode(MipsISD::Hi, DL, PtrVT, TGAHi);
1530    SDValue TGALo = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0,
1531                                               MipsII::MO_DTPREL_LO);
1532    SDValue Lo = DAG.getNode(MipsISD::Lo, DL, PtrVT, TGALo);
1533    SDValue Add = DAG.getNode(ISD::ADD, DL, PtrVT, Hi, Ret);
1534    return DAG.getNode(ISD::ADD, DL, PtrVT, Add, Lo);
1535  }
1536
1537  SDValue Offset;
1538  if (model == TLSModel::InitialExec) {
1539    // Initial Exec TLS Model
1540    SDValue TGA = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0,
1541                                             MipsII::MO_GOTTPREL);
1542    TGA = DAG.getNode(MipsISD::Wrapper, DL, PtrVT, getGlobalReg(DAG, PtrVT),
1543                      TGA);
1544    Offset = DAG.getLoad(PtrVT, DL,
1545                         DAG.getEntryNode(), TGA, MachinePointerInfo(),
1546                         false, false, false, 0);
1547  } else {
1548    // Local Exec TLS Model
1549    assert(model == TLSModel::LocalExec);
1550    SDValue TGAHi = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0,
1551                                               MipsII::MO_TPREL_HI);
1552    SDValue TGALo = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0,
1553                                               MipsII::MO_TPREL_LO);
1554    SDValue Hi = DAG.getNode(MipsISD::Hi, DL, PtrVT, TGAHi);
1555    SDValue Lo = DAG.getNode(MipsISD::Lo, DL, PtrVT, TGALo);
1556    Offset = DAG.getNode(ISD::ADD, DL, PtrVT, Hi, Lo);
1557  }
1558
1559  SDValue ThreadPointer = DAG.getNode(MipsISD::ThreadPointer, DL, PtrVT);
1560  return DAG.getNode(ISD::ADD, DL, PtrVT, ThreadPointer, Offset);
1561}
1562
1563SDValue MipsTargetLowering::
1564lowerJumpTable(SDValue Op, SelectionDAG &DAG) const
1565{
1566  if (getTargetMachine().getRelocationModel() != Reloc::PIC_ && !IsN64)
1567    return getAddrNonPIC(Op, DAG);
1568
1569  return getAddrLocal(Op, DAG, HasMips64);
1570}
1571
1572SDValue MipsTargetLowering::
1573lowerConstantPool(SDValue Op, SelectionDAG &DAG) const
1574{
1575  // gp_rel relocation
1576  // FIXME: we should reference the constant pool using small data sections,
1577  // but the asm printer currently doesn't support this feature without
1578  // hacking it. This feature should come soon so we can uncomment the
1579  // stuff below.
1580  //if (IsInSmallSection(C->getType())) {
1581  //  SDValue GPRelNode = DAG.getNode(MipsISD::GPRel, MVT::i32, CP);
1582  //  SDValue GOT = DAG.getGLOBAL_OFFSET_TABLE(MVT::i32);
1583  //  ResNode = DAG.getNode(ISD::ADD, MVT::i32, GOT, GPRelNode);
1584
1585  if (getTargetMachine().getRelocationModel() != Reloc::PIC_ && !IsN64)
1586    return getAddrNonPIC(Op, DAG);
1587
1588  return getAddrLocal(Op, DAG, HasMips64);
1589}
1590
1591SDValue MipsTargetLowering::lowerVASTART(SDValue Op, SelectionDAG &DAG) const {
1592  MachineFunction &MF = DAG.getMachineFunction();
1593  MipsFunctionInfo *FuncInfo = MF.getInfo<MipsFunctionInfo>();
1594
1595  DebugLoc DL = Op.getDebugLoc();
1596  SDValue FI = DAG.getFrameIndex(FuncInfo->getVarArgsFrameIndex(),
1597                                 getPointerTy());
1598
1599  // vastart just stores the address of the VarArgsFrameIndex slot into the
1600  // memory location argument.
1601  const Value *SV = cast<SrcValueSDNode>(Op.getOperand(2))->getValue();
1602  return DAG.getStore(Op.getOperand(0), DL, FI, Op.getOperand(1),
1603                      MachinePointerInfo(SV), false, false, 0);
1604}
1605
1606static SDValue lowerFCOPYSIGN32(SDValue Op, SelectionDAG &DAG, bool HasR2) {
1607  EVT TyX = Op.getOperand(0).getValueType();
1608  EVT TyY = Op.getOperand(1).getValueType();
1609  SDValue Const1 = DAG.getConstant(1, MVT::i32);
1610  SDValue Const31 = DAG.getConstant(31, MVT::i32);
1611  DebugLoc DL = Op.getDebugLoc();
1612  SDValue Res;
1613
1614  // If operand is of type f64, extract the upper 32-bit. Otherwise, bitcast it
1615  // to i32.
1616  SDValue X = (TyX == MVT::f32) ?
1617    DAG.getNode(ISD::BITCAST, DL, MVT::i32, Op.getOperand(0)) :
1618    DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32, Op.getOperand(0),
1619                Const1);
1620  SDValue Y = (TyY == MVT::f32) ?
1621    DAG.getNode(ISD::BITCAST, DL, MVT::i32, Op.getOperand(1)) :
1622    DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32, Op.getOperand(1),
1623                Const1);
1624
1625  if (HasR2) {
1626    // ext  E, Y, 31, 1  ; extract bit31 of Y
1627    // ins  X, E, 31, 1  ; insert extracted bit at bit31 of X
1628    SDValue E = DAG.getNode(MipsISD::Ext, DL, MVT::i32, Y, Const31, Const1);
1629    Res = DAG.getNode(MipsISD::Ins, DL, MVT::i32, E, Const31, Const1, X);
1630  } else {
1631    // sll SllX, X, 1
1632    // srl SrlX, SllX, 1
1633    // srl SrlY, Y, 31
1634    // sll SllY, SrlX, 31
1635    // or  Or, SrlX, SllY
1636    SDValue SllX = DAG.getNode(ISD::SHL, DL, MVT::i32, X, Const1);
1637    SDValue SrlX = DAG.getNode(ISD::SRL, DL, MVT::i32, SllX, Const1);
1638    SDValue SrlY = DAG.getNode(ISD::SRL, DL, MVT::i32, Y, Const31);
1639    SDValue SllY = DAG.getNode(ISD::SHL, DL, MVT::i32, SrlY, Const31);
1640    Res = DAG.getNode(ISD::OR, DL, MVT::i32, SrlX, SllY);
1641  }
1642
1643  if (TyX == MVT::f32)
1644    return DAG.getNode(ISD::BITCAST, DL, Op.getOperand(0).getValueType(), Res);
1645
1646  SDValue LowX = DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32,
1647                             Op.getOperand(0), DAG.getConstant(0, MVT::i32));
1648  return DAG.getNode(MipsISD::BuildPairF64, DL, MVT::f64, LowX, Res);
1649}
1650
1651static SDValue lowerFCOPYSIGN64(SDValue Op, SelectionDAG &DAG, bool HasR2) {
1652  unsigned WidthX = Op.getOperand(0).getValueSizeInBits();
1653  unsigned WidthY = Op.getOperand(1).getValueSizeInBits();
1654  EVT TyX = MVT::getIntegerVT(WidthX), TyY = MVT::getIntegerVT(WidthY);
1655  SDValue Const1 = DAG.getConstant(1, MVT::i32);
1656  DebugLoc DL = Op.getDebugLoc();
1657
1658  // Bitcast to integer nodes.
1659  SDValue X = DAG.getNode(ISD::BITCAST, DL, TyX, Op.getOperand(0));
1660  SDValue Y = DAG.getNode(ISD::BITCAST, DL, TyY, Op.getOperand(1));
1661
1662  if (HasR2) {
1663    // ext  E, Y, width(Y) - 1, 1  ; extract bit width(Y)-1 of Y
1664    // ins  X, E, width(X) - 1, 1  ; insert extracted bit at bit width(X)-1 of X
1665    SDValue E = DAG.getNode(MipsISD::Ext, DL, TyY, Y,
1666                            DAG.getConstant(WidthY - 1, MVT::i32), Const1);
1667
1668    if (WidthX > WidthY)
1669      E = DAG.getNode(ISD::ZERO_EXTEND, DL, TyX, E);
1670    else if (WidthY > WidthX)
1671      E = DAG.getNode(ISD::TRUNCATE, DL, TyX, E);
1672
1673    SDValue I = DAG.getNode(MipsISD::Ins, DL, TyX, E,
1674                            DAG.getConstant(WidthX - 1, MVT::i32), Const1, X);
1675    return DAG.getNode(ISD::BITCAST, DL, Op.getOperand(0).getValueType(), I);
1676  }
1677
1678  // (d)sll SllX, X, 1
1679  // (d)srl SrlX, SllX, 1
1680  // (d)srl SrlY, Y, width(Y)-1
1681  // (d)sll SllY, SrlX, width(Y)-1
1682  // or     Or, SrlX, SllY
1683  SDValue SllX = DAG.getNode(ISD::SHL, DL, TyX, X, Const1);
1684  SDValue SrlX = DAG.getNode(ISD::SRL, DL, TyX, SllX, Const1);
1685  SDValue SrlY = DAG.getNode(ISD::SRL, DL, TyY, Y,
1686                             DAG.getConstant(WidthY - 1, MVT::i32));
1687
1688  if (WidthX > WidthY)
1689    SrlY = DAG.getNode(ISD::ZERO_EXTEND, DL, TyX, SrlY);
1690  else if (WidthY > WidthX)
1691    SrlY = DAG.getNode(ISD::TRUNCATE, DL, TyX, SrlY);
1692
1693  SDValue SllY = DAG.getNode(ISD::SHL, DL, TyX, SrlY,
1694                             DAG.getConstant(WidthX - 1, MVT::i32));
1695  SDValue Or = DAG.getNode(ISD::OR, DL, TyX, SrlX, SllY);
1696  return DAG.getNode(ISD::BITCAST, DL, Op.getOperand(0).getValueType(), Or);
1697}
1698
1699SDValue
1700MipsTargetLowering::lowerFCOPYSIGN(SDValue Op, SelectionDAG &DAG) const {
1701  if (Subtarget->hasMips64())
1702    return lowerFCOPYSIGN64(Op, DAG, Subtarget->hasMips32r2());
1703
1704  return lowerFCOPYSIGN32(Op, DAG, Subtarget->hasMips32r2());
1705}
1706
1707static SDValue lowerFABS32(SDValue Op, SelectionDAG &DAG, bool HasR2) {
1708  SDValue Res, Const1 = DAG.getConstant(1, MVT::i32);
1709  DebugLoc DL = Op.getDebugLoc();
1710
1711  // If operand is of type f64, extract the upper 32-bit. Otherwise, bitcast it
1712  // to i32.
1713  SDValue X = (Op.getValueType() == MVT::f32) ?
1714    DAG.getNode(ISD::BITCAST, DL, MVT::i32, Op.getOperand(0)) :
1715    DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32, Op.getOperand(0),
1716                Const1);
1717
1718  // Clear MSB.
1719  if (HasR2)
1720    Res = DAG.getNode(MipsISD::Ins, DL, MVT::i32,
1721                      DAG.getRegister(Mips::ZERO, MVT::i32),
1722                      DAG.getConstant(31, MVT::i32), Const1, X);
1723  else {
1724    SDValue SllX = DAG.getNode(ISD::SHL, DL, MVT::i32, X, Const1);
1725    Res = DAG.getNode(ISD::SRL, DL, MVT::i32, SllX, Const1);
1726  }
1727
1728  if (Op.getValueType() == MVT::f32)
1729    return DAG.getNode(ISD::BITCAST, DL, MVT::f32, Res);
1730
1731  SDValue LowX = DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32,
1732                             Op.getOperand(0), DAG.getConstant(0, MVT::i32));
1733  return DAG.getNode(MipsISD::BuildPairF64, DL, MVT::f64, LowX, Res);
1734}
1735
1736static SDValue lowerFABS64(SDValue Op, SelectionDAG &DAG, bool HasR2) {
1737  SDValue Res, Const1 = DAG.getConstant(1, MVT::i32);
1738  DebugLoc DL = Op.getDebugLoc();
1739
1740  // Bitcast to integer node.
1741  SDValue X = DAG.getNode(ISD::BITCAST, DL, MVT::i64, Op.getOperand(0));
1742
1743  // Clear MSB.
1744  if (HasR2)
1745    Res = DAG.getNode(MipsISD::Ins, DL, MVT::i64,
1746                      DAG.getRegister(Mips::ZERO_64, MVT::i64),
1747                      DAG.getConstant(63, MVT::i32), Const1, X);
1748  else {
1749    SDValue SllX = DAG.getNode(ISD::SHL, DL, MVT::i64, X, Const1);
1750    Res = DAG.getNode(ISD::SRL, DL, MVT::i64, SllX, Const1);
1751  }
1752
1753  return DAG.getNode(ISD::BITCAST, DL, MVT::f64, Res);
1754}
1755
1756SDValue
1757MipsTargetLowering::lowerFABS(SDValue Op, SelectionDAG &DAG) const {
1758  if (Subtarget->hasMips64() && (Op.getValueType() == MVT::f64))
1759    return lowerFABS64(Op, DAG, Subtarget->hasMips32r2());
1760
1761  return lowerFABS32(Op, DAG, Subtarget->hasMips32r2());
1762}
1763
1764SDValue MipsTargetLowering::
1765lowerFRAMEADDR(SDValue Op, SelectionDAG &DAG) const {
1766  // check the depth
1767  assert((cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue() == 0) &&
1768         "Frame address can only be determined for current frame.");
1769
1770  MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo();
1771  MFI->setFrameAddressIsTaken(true);
1772  EVT VT = Op.getValueType();
1773  DebugLoc DL = Op.getDebugLoc();
1774  SDValue FrameAddr = DAG.getCopyFromReg(DAG.getEntryNode(), DL,
1775                                         IsN64 ? Mips::FP_64 : Mips::FP, VT);
1776  return FrameAddr;
1777}
1778
1779SDValue MipsTargetLowering::lowerRETURNADDR(SDValue Op,
1780                                            SelectionDAG &DAG) const {
1781  // check the depth
1782  assert((cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue() == 0) &&
1783         "Return address can be determined only for current frame.");
1784
1785  MachineFunction &MF = DAG.getMachineFunction();
1786  MachineFrameInfo *MFI = MF.getFrameInfo();
1787  MVT VT = Op.getSimpleValueType();
1788  unsigned RA = IsN64 ? Mips::RA_64 : Mips::RA;
1789  MFI->setReturnAddressIsTaken(true);
1790
1791  // Return RA, which contains the return address. Mark it an implicit live-in.
1792  unsigned Reg = MF.addLiveIn(RA, getRegClassFor(VT));
1793  return DAG.getCopyFromReg(DAG.getEntryNode(), Op.getDebugLoc(), Reg, VT);
1794}
1795
1796// An EH_RETURN is the result of lowering llvm.eh.return which in turn is
1797// generated from __builtin_eh_return (offset, handler)
1798// The effect of this is to adjust the stack pointer by "offset"
1799// and then branch to "handler".
1800SDValue MipsTargetLowering::lowerEH_RETURN(SDValue Op, SelectionDAG &DAG)
1801                                                                     const {
1802  MachineFunction &MF = DAG.getMachineFunction();
1803  MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
1804
1805  MipsFI->setCallsEhReturn();
1806  SDValue Chain     = Op.getOperand(0);
1807  SDValue Offset    = Op.getOperand(1);
1808  SDValue Handler   = Op.getOperand(2);
1809  DebugLoc DL       = Op.getDebugLoc();
1810  EVT Ty = IsN64 ? MVT::i64 : MVT::i32;
1811
1812  // Store stack offset in V1, store jump target in V0. Glue CopyToReg and
1813  // EH_RETURN nodes, so that instructions are emitted back-to-back.
1814  unsigned OffsetReg = IsN64 ? Mips::V1_64 : Mips::V1;
1815  unsigned AddrReg = IsN64 ? Mips::V0_64 : Mips::V0;
1816  Chain = DAG.getCopyToReg(Chain, DL, OffsetReg, Offset, SDValue());
1817  Chain = DAG.getCopyToReg(Chain, DL, AddrReg, Handler, Chain.getValue(1));
1818  return DAG.getNode(MipsISD::EH_RETURN, DL, MVT::Other, Chain,
1819                     DAG.getRegister(OffsetReg, Ty),
1820                     DAG.getRegister(AddrReg, getPointerTy()),
1821                     Chain.getValue(1));
1822}
1823
1824// TODO: set SType according to the desired memory barrier behavior.
1825SDValue
1826MipsTargetLowering::lowerMEMBARRIER(SDValue Op, SelectionDAG &DAG) const {
1827  unsigned SType = 0;
1828  DebugLoc DL = Op.getDebugLoc();
1829  return DAG.getNode(MipsISD::Sync, DL, MVT::Other, Op.getOperand(0),
1830                     DAG.getConstant(SType, MVT::i32));
1831}
1832
1833SDValue MipsTargetLowering::lowerATOMIC_FENCE(SDValue Op,
1834                                              SelectionDAG &DAG) const {
1835  // FIXME: Need pseudo-fence for 'singlethread' fences
1836  // FIXME: Set SType for weaker fences where supported/appropriate.
1837  unsigned SType = 0;
1838  DebugLoc DL = Op.getDebugLoc();
1839  return DAG.getNode(MipsISD::Sync, DL, MVT::Other, Op.getOperand(0),
1840                     DAG.getConstant(SType, MVT::i32));
1841}
1842
1843SDValue MipsTargetLowering::lowerShiftLeftParts(SDValue Op,
1844                                                SelectionDAG &DAG) const {
1845  DebugLoc DL = Op.getDebugLoc();
1846  SDValue Lo = Op.getOperand(0), Hi = Op.getOperand(1);
1847  SDValue Shamt = Op.getOperand(2);
1848
1849  // if shamt < 32:
1850  //  lo = (shl lo, shamt)
1851  //  hi = (or (shl hi, shamt) (srl (srl lo, 1), ~shamt))
1852  // else:
1853  //  lo = 0
1854  //  hi = (shl lo, shamt[4:0])
1855  SDValue Not = DAG.getNode(ISD::XOR, DL, MVT::i32, Shamt,
1856                            DAG.getConstant(-1, MVT::i32));
1857  SDValue ShiftRight1Lo = DAG.getNode(ISD::SRL, DL, MVT::i32, Lo,
1858                                      DAG.getConstant(1, MVT::i32));
1859  SDValue ShiftRightLo = DAG.getNode(ISD::SRL, DL, MVT::i32, ShiftRight1Lo,
1860                                     Not);
1861  SDValue ShiftLeftHi = DAG.getNode(ISD::SHL, DL, MVT::i32, Hi, Shamt);
1862  SDValue Or = DAG.getNode(ISD::OR, DL, MVT::i32, ShiftLeftHi, ShiftRightLo);
1863  SDValue ShiftLeftLo = DAG.getNode(ISD::SHL, DL, MVT::i32, Lo, Shamt);
1864  SDValue Cond = DAG.getNode(ISD::AND, DL, MVT::i32, Shamt,
1865                             DAG.getConstant(0x20, MVT::i32));
1866  Lo = DAG.getNode(ISD::SELECT, DL, MVT::i32, Cond,
1867                   DAG.getConstant(0, MVT::i32), ShiftLeftLo);
1868  Hi = DAG.getNode(ISD::SELECT, DL, MVT::i32, Cond, ShiftLeftLo, Or);
1869
1870  SDValue Ops[2] = {Lo, Hi};
1871  return DAG.getMergeValues(Ops, 2, DL);
1872}
1873
1874SDValue MipsTargetLowering::lowerShiftRightParts(SDValue Op, SelectionDAG &DAG,
1875                                                 bool IsSRA) const {
1876  DebugLoc DL = Op.getDebugLoc();
1877  SDValue Lo = Op.getOperand(0), Hi = Op.getOperand(1);
1878  SDValue Shamt = Op.getOperand(2);
1879
1880  // if shamt < 32:
1881  //  lo = (or (shl (shl hi, 1), ~shamt) (srl lo, shamt))
1882  //  if isSRA:
1883  //    hi = (sra hi, shamt)
1884  //  else:
1885  //    hi = (srl hi, shamt)
1886  // else:
1887  //  if isSRA:
1888  //   lo = (sra hi, shamt[4:0])
1889  //   hi = (sra hi, 31)
1890  //  else:
1891  //   lo = (srl hi, shamt[4:0])
1892  //   hi = 0
1893  SDValue Not = DAG.getNode(ISD::XOR, DL, MVT::i32, Shamt,
1894                            DAG.getConstant(-1, MVT::i32));
1895  SDValue ShiftLeft1Hi = DAG.getNode(ISD::SHL, DL, MVT::i32, Hi,
1896                                     DAG.getConstant(1, MVT::i32));
1897  SDValue ShiftLeftHi = DAG.getNode(ISD::SHL, DL, MVT::i32, ShiftLeft1Hi, Not);
1898  SDValue ShiftRightLo = DAG.getNode(ISD::SRL, DL, MVT::i32, Lo, Shamt);
1899  SDValue Or = DAG.getNode(ISD::OR, DL, MVT::i32, ShiftLeftHi, ShiftRightLo);
1900  SDValue ShiftRightHi = DAG.getNode(IsSRA ? ISD::SRA : ISD::SRL, DL, MVT::i32,
1901                                     Hi, Shamt);
1902  SDValue Cond = DAG.getNode(ISD::AND, DL, MVT::i32, Shamt,
1903                             DAG.getConstant(0x20, MVT::i32));
1904  SDValue Shift31 = DAG.getNode(ISD::SRA, DL, MVT::i32, Hi,
1905                                DAG.getConstant(31, MVT::i32));
1906  Lo = DAG.getNode(ISD::SELECT, DL, MVT::i32, Cond, ShiftRightHi, Or);
1907  Hi = DAG.getNode(ISD::SELECT, DL, MVT::i32, Cond,
1908                   IsSRA ? Shift31 : DAG.getConstant(0, MVT::i32),
1909                   ShiftRightHi);
1910
1911  SDValue Ops[2] = {Lo, Hi};
1912  return DAG.getMergeValues(Ops, 2, DL);
1913}
1914
1915static SDValue createLoadLR(unsigned Opc, SelectionDAG &DAG, LoadSDNode *LD,
1916                            SDValue Chain, SDValue Src, unsigned Offset) {
1917  SDValue Ptr = LD->getBasePtr();
1918  EVT VT = LD->getValueType(0), MemVT = LD->getMemoryVT();
1919  EVT BasePtrVT = Ptr.getValueType();
1920  DebugLoc DL = LD->getDebugLoc();
1921  SDVTList VTList = DAG.getVTList(VT, MVT::Other);
1922
1923  if (Offset)
1924    Ptr = DAG.getNode(ISD::ADD, DL, BasePtrVT, Ptr,
1925                      DAG.getConstant(Offset, BasePtrVT));
1926
1927  SDValue Ops[] = { Chain, Ptr, Src };
1928  return DAG.getMemIntrinsicNode(Opc, DL, VTList, Ops, 3, MemVT,
1929                                 LD->getMemOperand());
1930}
1931
1932// Expand an unaligned 32 or 64-bit integer load node.
1933SDValue MipsTargetLowering::lowerLOAD(SDValue Op, SelectionDAG &DAG) const {
1934  LoadSDNode *LD = cast<LoadSDNode>(Op);
1935  EVT MemVT = LD->getMemoryVT();
1936
1937  // Return if load is aligned or if MemVT is neither i32 nor i64.
1938  if ((LD->getAlignment() >= MemVT.getSizeInBits() / 8) ||
1939      ((MemVT != MVT::i32) && (MemVT != MVT::i64)))
1940    return SDValue();
1941
1942  bool IsLittle = Subtarget->isLittle();
1943  EVT VT = Op.getValueType();
1944  ISD::LoadExtType ExtType = LD->getExtensionType();
1945  SDValue Chain = LD->getChain(), Undef = DAG.getUNDEF(VT);
1946
1947  assert((VT == MVT::i32) || (VT == MVT::i64));
1948
1949  // Expand
1950  //  (set dst, (i64 (load baseptr)))
1951  // to
1952  //  (set tmp, (ldl (add baseptr, 7), undef))
1953  //  (set dst, (ldr baseptr, tmp))
1954  if ((VT == MVT::i64) && (ExtType == ISD::NON_EXTLOAD)) {
1955    SDValue LDL = createLoadLR(MipsISD::LDL, DAG, LD, Chain, Undef,
1956                               IsLittle ? 7 : 0);
1957    return createLoadLR(MipsISD::LDR, DAG, LD, LDL.getValue(1), LDL,
1958                        IsLittle ? 0 : 7);
1959  }
1960
1961  SDValue LWL = createLoadLR(MipsISD::LWL, DAG, LD, Chain, Undef,
1962                             IsLittle ? 3 : 0);
1963  SDValue LWR = createLoadLR(MipsISD::LWR, DAG, LD, LWL.getValue(1), LWL,
1964                             IsLittle ? 0 : 3);
1965
1966  // Expand
1967  //  (set dst, (i32 (load baseptr))) or
1968  //  (set dst, (i64 (sextload baseptr))) or
1969  //  (set dst, (i64 (extload baseptr)))
1970  // to
1971  //  (set tmp, (lwl (add baseptr, 3), undef))
1972  //  (set dst, (lwr baseptr, tmp))
1973  if ((VT == MVT::i32) || (ExtType == ISD::SEXTLOAD) ||
1974      (ExtType == ISD::EXTLOAD))
1975    return LWR;
1976
1977  assert((VT == MVT::i64) && (ExtType == ISD::ZEXTLOAD));
1978
1979  // Expand
1980  //  (set dst, (i64 (zextload baseptr)))
1981  // to
1982  //  (set tmp0, (lwl (add baseptr, 3), undef))
1983  //  (set tmp1, (lwr baseptr, tmp0))
1984  //  (set tmp2, (shl tmp1, 32))
1985  //  (set dst, (srl tmp2, 32))
1986  DebugLoc DL = LD->getDebugLoc();
1987  SDValue Const32 = DAG.getConstant(32, MVT::i32);
1988  SDValue SLL = DAG.getNode(ISD::SHL, DL, MVT::i64, LWR, Const32);
1989  SDValue SRL = DAG.getNode(ISD::SRL, DL, MVT::i64, SLL, Const32);
1990  SDValue Ops[] = { SRL, LWR.getValue(1) };
1991  return DAG.getMergeValues(Ops, 2, DL);
1992}
1993
1994static SDValue createStoreLR(unsigned Opc, SelectionDAG &DAG, StoreSDNode *SD,
1995                             SDValue Chain, unsigned Offset) {
1996  SDValue Ptr = SD->getBasePtr(), Value = SD->getValue();
1997  EVT MemVT = SD->getMemoryVT(), BasePtrVT = Ptr.getValueType();
1998  DebugLoc DL = SD->getDebugLoc();
1999  SDVTList VTList = DAG.getVTList(MVT::Other);
2000
2001  if (Offset)
2002    Ptr = DAG.getNode(ISD::ADD, DL, BasePtrVT, Ptr,
2003                      DAG.getConstant(Offset, BasePtrVT));
2004
2005  SDValue Ops[] = { Chain, Value, Ptr };
2006  return DAG.getMemIntrinsicNode(Opc, DL, VTList, Ops, 3, MemVT,
2007                                 SD->getMemOperand());
2008}
2009
2010// Expand an unaligned 32 or 64-bit integer store node.
2011SDValue MipsTargetLowering::lowerSTORE(SDValue Op, SelectionDAG &DAG) const {
2012  StoreSDNode *SD = cast<StoreSDNode>(Op);
2013  EVT MemVT = SD->getMemoryVT();
2014
2015  // Return if store is aligned or if MemVT is neither i32 nor i64.
2016  if ((SD->getAlignment() >= MemVT.getSizeInBits() / 8) ||
2017      ((MemVT != MVT::i32) && (MemVT != MVT::i64)))
2018    return SDValue();
2019
2020  bool IsLittle = Subtarget->isLittle();
2021  SDValue Value = SD->getValue(), Chain = SD->getChain();
2022  EVT VT = Value.getValueType();
2023
2024  // Expand
2025  //  (store val, baseptr) or
2026  //  (truncstore val, baseptr)
2027  // to
2028  //  (swl val, (add baseptr, 3))
2029  //  (swr val, baseptr)
2030  if ((VT == MVT::i32) || SD->isTruncatingStore()) {
2031    SDValue SWL = createStoreLR(MipsISD::SWL, DAG, SD, Chain,
2032                                IsLittle ? 3 : 0);
2033    return createStoreLR(MipsISD::SWR, DAG, SD, SWL, IsLittle ? 0 : 3);
2034  }
2035
2036  assert(VT == MVT::i64);
2037
2038  // Expand
2039  //  (store val, baseptr)
2040  // to
2041  //  (sdl val, (add baseptr, 7))
2042  //  (sdr val, baseptr)
2043  SDValue SDL = createStoreLR(MipsISD::SDL, DAG, SD, Chain, IsLittle ? 7 : 0);
2044  return createStoreLR(MipsISD::SDR, DAG, SD, SDL, IsLittle ? 0 : 7);
2045}
2046
2047SDValue MipsTargetLowering::lowerADD(SDValue Op, SelectionDAG &DAG) const {
2048  if (Op->getOperand(0).getOpcode() != ISD::FRAMEADDR
2049      || cast<ConstantSDNode>
2050        (Op->getOperand(0).getOperand(0))->getZExtValue() != 0
2051      || Op->getOperand(1).getOpcode() != ISD::FRAME_TO_ARGS_OFFSET)
2052    return SDValue();
2053
2054  // The pattern
2055  //   (add (frameaddr 0), (frame_to_args_offset))
2056  // results from lowering llvm.eh.dwarf.cfa intrinsic. Transform it to
2057  //   (add FrameObject, 0)
2058  // where FrameObject is a fixed StackObject with offset 0 which points to
2059  // the old stack pointer.
2060  MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo();
2061  EVT ValTy = Op->getValueType(0);
2062  int FI = MFI->CreateFixedObject(Op.getValueSizeInBits() / 8, 0, false);
2063  SDValue InArgsAddr = DAG.getFrameIndex(FI, ValTy);
2064  return DAG.getNode(ISD::ADD, Op->getDebugLoc(), ValTy, InArgsAddr,
2065                     DAG.getConstant(0, ValTy));
2066}
2067
2068//===----------------------------------------------------------------------===//
2069//                      Calling Convention Implementation
2070//===----------------------------------------------------------------------===//
2071
2072//===----------------------------------------------------------------------===//
2073// TODO: Implement a generic logic using tblgen that can support this.
2074// Mips O32 ABI rules:
2075// ---
2076// i32 - Passed in A0, A1, A2, A3 and stack
2077// f32 - Only passed in f32 registers if no int reg has been used yet to hold
2078//       an argument. Otherwise, passed in A1, A2, A3 and stack.
2079// f64 - Only passed in two aliased f32 registers if no int reg has been used
2080//       yet to hold an argument. Otherwise, use A2, A3 and stack. If A1 is
2081//       not used, it must be shadowed. If only A3 is avaiable, shadow it and
2082//       go to stack.
2083//
2084//  For vararg functions, all arguments are passed in A0, A1, A2, A3 and stack.
2085//===----------------------------------------------------------------------===//
2086
2087static bool CC_MipsO32(unsigned ValNo, MVT ValVT,
2088                       MVT LocVT, CCValAssign::LocInfo LocInfo,
2089                       ISD::ArgFlagsTy ArgFlags, CCState &State) {
2090
2091  static const unsigned IntRegsSize=4, FloatRegsSize=2;
2092
2093  static const uint16_t IntRegs[] = {
2094      Mips::A0, Mips::A1, Mips::A2, Mips::A3
2095  };
2096  static const uint16_t F32Regs[] = {
2097      Mips::F12, Mips::F14
2098  };
2099  static const uint16_t F64Regs[] = {
2100      Mips::D6, Mips::D7
2101  };
2102
2103  // Do not process byval args here.
2104  if (ArgFlags.isByVal())
2105    return true;
2106
2107  // Promote i8 and i16
2108  if (LocVT == MVT::i8 || LocVT == MVT::i16) {
2109    LocVT = MVT::i32;
2110    if (ArgFlags.isSExt())
2111      LocInfo = CCValAssign::SExt;
2112    else if (ArgFlags.isZExt())
2113      LocInfo = CCValAssign::ZExt;
2114    else
2115      LocInfo = CCValAssign::AExt;
2116  }
2117
2118  unsigned Reg;
2119
2120  // f32 and f64 are allocated in A0, A1, A2, A3 when either of the following
2121  // is true: function is vararg, argument is 3rd or higher, there is previous
2122  // argument which is not f32 or f64.
2123  bool AllocateFloatsInIntReg = State.isVarArg() || ValNo > 1
2124      || State.getFirstUnallocated(F32Regs, FloatRegsSize) != ValNo;
2125  unsigned OrigAlign = ArgFlags.getOrigAlign();
2126  bool isI64 = (ValVT == MVT::i32 && OrigAlign == 8);
2127
2128  if (ValVT == MVT::i32 || (ValVT == MVT::f32 && AllocateFloatsInIntReg)) {
2129    Reg = State.AllocateReg(IntRegs, IntRegsSize);
2130    // If this is the first part of an i64 arg,
2131    // the allocated register must be either A0 or A2.
2132    if (isI64 && (Reg == Mips::A1 || Reg == Mips::A3))
2133      Reg = State.AllocateReg(IntRegs, IntRegsSize);
2134    LocVT = MVT::i32;
2135  } else if (ValVT == MVT::f64 && AllocateFloatsInIntReg) {
2136    // Allocate int register and shadow next int register. If first
2137    // available register is Mips::A1 or Mips::A3, shadow it too.
2138    Reg = State.AllocateReg(IntRegs, IntRegsSize);
2139    if (Reg == Mips::A1 || Reg == Mips::A3)
2140      Reg = State.AllocateReg(IntRegs, IntRegsSize);
2141    State.AllocateReg(IntRegs, IntRegsSize);
2142    LocVT = MVT::i32;
2143  } else if (ValVT.isFloatingPoint() && !AllocateFloatsInIntReg) {
2144    // we are guaranteed to find an available float register
2145    if (ValVT == MVT::f32) {
2146      Reg = State.AllocateReg(F32Regs, FloatRegsSize);
2147      // Shadow int register
2148      State.AllocateReg(IntRegs, IntRegsSize);
2149    } else {
2150      Reg = State.AllocateReg(F64Regs, FloatRegsSize);
2151      // Shadow int registers
2152      unsigned Reg2 = State.AllocateReg(IntRegs, IntRegsSize);
2153      if (Reg2 == Mips::A1 || Reg2 == Mips::A3)
2154        State.AllocateReg(IntRegs, IntRegsSize);
2155      State.AllocateReg(IntRegs, IntRegsSize);
2156    }
2157  } else
2158    llvm_unreachable("Cannot handle this ValVT.");
2159
2160  if (!Reg) {
2161    unsigned Offset = State.AllocateStack(ValVT.getSizeInBits() >> 3,
2162                                          OrigAlign);
2163    State.addLoc(CCValAssign::getMem(ValNo, ValVT, Offset, LocVT, LocInfo));
2164  } else
2165    State.addLoc(CCValAssign::getReg(ValNo, ValVT, Reg, LocVT, LocInfo));
2166
2167  return false;
2168}
2169
2170#include "MipsGenCallingConv.inc"
2171
2172//===----------------------------------------------------------------------===//
2173//                  Call Calling Convention Implementation
2174//===----------------------------------------------------------------------===//
2175
2176static const unsigned O32IntRegsSize = 4;
2177
2178// Return next O32 integer argument register.
2179static unsigned getNextIntArgReg(unsigned Reg) {
2180  assert((Reg == Mips::A0) || (Reg == Mips::A2));
2181  return (Reg == Mips::A0) ? Mips::A1 : Mips::A3;
2182}
2183
2184SDValue
2185MipsTargetLowering::passArgOnStack(SDValue StackPtr, unsigned Offset,
2186                                   SDValue Chain, SDValue Arg, DebugLoc DL,
2187                                   bool IsTailCall, SelectionDAG &DAG) const {
2188  if (!IsTailCall) {
2189    SDValue PtrOff = DAG.getNode(ISD::ADD, DL, getPointerTy(), StackPtr,
2190                                 DAG.getIntPtrConstant(Offset));
2191    return DAG.getStore(Chain, DL, Arg, PtrOff, MachinePointerInfo(), false,
2192                        false, 0);
2193  }
2194
2195  MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo();
2196  int FI = MFI->CreateFixedObject(Arg.getValueSizeInBits() / 8, Offset, false);
2197  SDValue FIN = DAG.getFrameIndex(FI, getPointerTy());
2198  return DAG.getStore(Chain, DL, Arg, FIN, MachinePointerInfo(),
2199                      /*isVolatile=*/ true, false, 0);
2200}
2201
2202void MipsTargetLowering::
2203getOpndList(SmallVectorImpl<SDValue> &Ops,
2204            std::deque< std::pair<unsigned, SDValue> > &RegsToPass,
2205            bool IsPICCall, bool GlobalOrExternal, bool InternalLinkage,
2206            CallLoweringInfo &CLI, SDValue Callee, SDValue Chain) const {
2207  // Insert node "GP copy globalreg" before call to function.
2208  //
2209  // R_MIPS_CALL* operators (emitted when non-internal functions are called
2210  // in PIC mode) allow symbols to be resolved via lazy binding.
2211  // The lazy binding stub requires GP to point to the GOT.
2212  if (IsPICCall && !InternalLinkage) {
2213    unsigned GPReg = IsN64 ? Mips::GP_64 : Mips::GP;
2214    EVT Ty = IsN64 ? MVT::i64 : MVT::i32;
2215    RegsToPass.push_back(std::make_pair(GPReg, getGlobalReg(CLI.DAG, Ty)));
2216  }
2217
2218  // Build a sequence of copy-to-reg nodes chained together with token
2219  // chain and flag operands which copy the outgoing args into registers.
2220  // The InFlag in necessary since all emitted instructions must be
2221  // stuck together.
2222  SDValue InFlag;
2223
2224  for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i) {
2225    Chain = CLI.DAG.getCopyToReg(Chain, CLI.DL, RegsToPass[i].first,
2226                                 RegsToPass[i].second, InFlag);
2227    InFlag = Chain.getValue(1);
2228  }
2229
2230  // Add argument registers to the end of the list so that they are
2231  // known live into the call.
2232  for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i)
2233    Ops.push_back(CLI.DAG.getRegister(RegsToPass[i].first,
2234                                      RegsToPass[i].second.getValueType()));
2235
2236  // Add a register mask operand representing the call-preserved registers.
2237  const TargetRegisterInfo *TRI = getTargetMachine().getRegisterInfo();
2238  const uint32_t *Mask = TRI->getCallPreservedMask(CLI.CallConv);
2239  assert(Mask && "Missing call preserved mask for calling convention");
2240  Ops.push_back(CLI.DAG.getRegisterMask(Mask));
2241
2242  if (InFlag.getNode())
2243    Ops.push_back(InFlag);
2244}
2245
2246/// LowerCall - functions arguments are copied from virtual regs to
2247/// (physical regs)/(stack frame), CALLSEQ_START and CALLSEQ_END are emitted.
2248SDValue
2249MipsTargetLowering::LowerCall(TargetLowering::CallLoweringInfo &CLI,
2250                              SmallVectorImpl<SDValue> &InVals) const {
2251  SelectionDAG &DAG                     = CLI.DAG;
2252  DebugLoc &DL                          = CLI.DL;
2253  SmallVector<ISD::OutputArg, 32> &Outs = CLI.Outs;
2254  SmallVector<SDValue, 32> &OutVals     = CLI.OutVals;
2255  SmallVector<ISD::InputArg, 32> &Ins   = CLI.Ins;
2256  SDValue Chain                         = CLI.Chain;
2257  SDValue Callee                        = CLI.Callee;
2258  bool &IsTailCall                      = CLI.IsTailCall;
2259  CallingConv::ID CallConv              = CLI.CallConv;
2260  bool IsVarArg                         = CLI.IsVarArg;
2261
2262  MachineFunction &MF = DAG.getMachineFunction();
2263  MachineFrameInfo *MFI = MF.getFrameInfo();
2264  const TargetFrameLowering *TFL = MF.getTarget().getFrameLowering();
2265  bool IsPIC = getTargetMachine().getRelocationModel() == Reloc::PIC_;
2266
2267  // Analyze operands of the call, assigning locations to each operand.
2268  SmallVector<CCValAssign, 16> ArgLocs;
2269  CCState CCInfo(CallConv, IsVarArg, DAG.getMachineFunction(),
2270                 getTargetMachine(), ArgLocs, *DAG.getContext());
2271  MipsCC MipsCCInfo(CallConv, IsO32, CCInfo);
2272
2273  MipsCCInfo.analyzeCallOperands(Outs, IsVarArg,
2274                                 getTargetMachine().Options.UseSoftFloat,
2275                                 Callee.getNode(), CLI.Args);
2276
2277  // Get a count of how many bytes are to be pushed on the stack.
2278  unsigned NextStackOffset = CCInfo.getNextStackOffset();
2279
2280  // Check if it's really possible to do a tail call.
2281  if (IsTailCall)
2282    IsTailCall =
2283      isEligibleForTailCallOptimization(MipsCCInfo, NextStackOffset,
2284                                        *MF.getInfo<MipsFunctionInfo>());
2285
2286  if (IsTailCall)
2287    ++NumTailCalls;
2288
2289  // Chain is the output chain of the last Load/Store or CopyToReg node.
2290  // ByValChain is the output chain of the last Memcpy node created for copying
2291  // byval arguments to the stack.
2292  unsigned StackAlignment = TFL->getStackAlignment();
2293  NextStackOffset = RoundUpToAlignment(NextStackOffset, StackAlignment);
2294  SDValue NextStackOffsetVal = DAG.getIntPtrConstant(NextStackOffset, true);
2295
2296  if (!IsTailCall)
2297    Chain = DAG.getCALLSEQ_START(Chain, NextStackOffsetVal);
2298
2299  SDValue StackPtr = DAG.getCopyFromReg(Chain, DL,
2300                                        IsN64 ? Mips::SP_64 : Mips::SP,
2301                                        getPointerTy());
2302
2303  // With EABI is it possible to have 16 args on registers.
2304  std::deque< std::pair<unsigned, SDValue> > RegsToPass;
2305  SmallVector<SDValue, 8> MemOpChains;
2306  MipsCC::byval_iterator ByValArg = MipsCCInfo.byval_begin();
2307
2308  // Walk the register/memloc assignments, inserting copies/loads.
2309  for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
2310    SDValue Arg = OutVals[i];
2311    CCValAssign &VA = ArgLocs[i];
2312    MVT ValVT = VA.getValVT(), LocVT = VA.getLocVT();
2313    ISD::ArgFlagsTy Flags = Outs[i].Flags;
2314
2315    // ByVal Arg.
2316    if (Flags.isByVal()) {
2317      assert(Flags.getByValSize() &&
2318             "ByVal args of size 0 should have been ignored by front-end.");
2319      assert(ByValArg != MipsCCInfo.byval_end());
2320      assert(!IsTailCall &&
2321             "Do not tail-call optimize if there is a byval argument.");
2322      passByValArg(Chain, DL, RegsToPass, MemOpChains, StackPtr, MFI, DAG, Arg,
2323                   MipsCCInfo, *ByValArg, Flags, Subtarget->isLittle());
2324      ++ByValArg;
2325      continue;
2326    }
2327
2328    // Promote the value if needed.
2329    switch (VA.getLocInfo()) {
2330    default: llvm_unreachable("Unknown loc info!");
2331    case CCValAssign::Full:
2332      if (VA.isRegLoc()) {
2333        if ((ValVT == MVT::f32 && LocVT == MVT::i32) ||
2334            (ValVT == MVT::f64 && LocVT == MVT::i64) ||
2335            (ValVT == MVT::i64 && LocVT == MVT::f64))
2336          Arg = DAG.getNode(ISD::BITCAST, DL, LocVT, Arg);
2337        else if (ValVT == MVT::f64 && LocVT == MVT::i32) {
2338          SDValue Lo = DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32,
2339                                   Arg, DAG.getConstant(0, MVT::i32));
2340          SDValue Hi = DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32,
2341                                   Arg, DAG.getConstant(1, MVT::i32));
2342          if (!Subtarget->isLittle())
2343            std::swap(Lo, Hi);
2344          unsigned LocRegLo = VA.getLocReg();
2345          unsigned LocRegHigh = getNextIntArgReg(LocRegLo);
2346          RegsToPass.push_back(std::make_pair(LocRegLo, Lo));
2347          RegsToPass.push_back(std::make_pair(LocRegHigh, Hi));
2348          continue;
2349        }
2350      }
2351      break;
2352    case CCValAssign::SExt:
2353      Arg = DAG.getNode(ISD::SIGN_EXTEND, DL, LocVT, Arg);
2354      break;
2355    case CCValAssign::ZExt:
2356      Arg = DAG.getNode(ISD::ZERO_EXTEND, DL, LocVT, Arg);
2357      break;
2358    case CCValAssign::AExt:
2359      Arg = DAG.getNode(ISD::ANY_EXTEND, DL, LocVT, Arg);
2360      break;
2361    }
2362
2363    // Arguments that can be passed on register must be kept at
2364    // RegsToPass vector
2365    if (VA.isRegLoc()) {
2366      RegsToPass.push_back(std::make_pair(VA.getLocReg(), Arg));
2367      continue;
2368    }
2369
2370    // Register can't get to this point...
2371    assert(VA.isMemLoc());
2372
2373    // emit ISD::STORE whichs stores the
2374    // parameter value to a stack Location
2375    MemOpChains.push_back(passArgOnStack(StackPtr, VA.getLocMemOffset(),
2376                                         Chain, Arg, DL, IsTailCall, DAG));
2377  }
2378
2379  // Transform all store nodes into one single node because all store
2380  // nodes are independent of each other.
2381  if (!MemOpChains.empty())
2382    Chain = DAG.getNode(ISD::TokenFactor, DL, MVT::Other,
2383                        &MemOpChains[0], MemOpChains.size());
2384
2385  // If the callee is a GlobalAddress/ExternalSymbol node (quite common, every
2386  // direct call is) turn it into a TargetGlobalAddress/TargetExternalSymbol
2387  // node so that legalize doesn't hack it.
2388  bool IsPICCall = (IsN64 || IsPIC); // true if calls are translated to jalr $25
2389  bool GlobalOrExternal = false, InternalLinkage = false;
2390  SDValue CalleeLo;
2391
2392  if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee)) {
2393    if (IsPICCall) {
2394      InternalLinkage = G->getGlobal()->hasInternalLinkage();
2395
2396      if (InternalLinkage)
2397        Callee = getAddrLocal(Callee, DAG, HasMips64);
2398      else if (LargeGOT)
2399        Callee = getAddrGlobalLargeGOT(Callee, DAG, MipsII::MO_CALL_HI16,
2400                                       MipsII::MO_CALL_LO16);
2401      else
2402        Callee = getAddrGlobal(Callee, DAG, MipsII::MO_GOT_CALL);
2403    } else
2404      Callee = DAG.getTargetGlobalAddress(G->getGlobal(), DL, getPointerTy(), 0,
2405                                          MipsII::MO_NO_FLAG);
2406    GlobalOrExternal = true;
2407  }
2408  else if (ExternalSymbolSDNode *S = dyn_cast<ExternalSymbolSDNode>(Callee)) {
2409    if (!IsN64 && !IsPIC) // !N64 && static
2410      Callee = DAG.getTargetExternalSymbol(S->getSymbol(), getPointerTy(),
2411                                            MipsII::MO_NO_FLAG);
2412    else if (LargeGOT)
2413      Callee = getAddrGlobalLargeGOT(Callee, DAG, MipsII::MO_CALL_HI16,
2414                                     MipsII::MO_CALL_LO16);
2415    else // N64 || PIC
2416      Callee = getAddrGlobal(Callee, DAG, MipsII::MO_GOT_CALL);
2417
2418    GlobalOrExternal = true;
2419  }
2420
2421  SmallVector<SDValue, 8> Ops(1, Chain);
2422  SDVTList NodeTys = DAG.getVTList(MVT::Other, MVT::Glue);
2423
2424  getOpndList(Ops, RegsToPass, IsPICCall, GlobalOrExternal, InternalLinkage,
2425              CLI, Callee, Chain);
2426
2427  if (IsTailCall)
2428    return DAG.getNode(MipsISD::TailCall, DL, MVT::Other, &Ops[0], Ops.size());
2429
2430  Chain  = DAG.getNode(MipsISD::JmpLink, DL, NodeTys, &Ops[0], Ops.size());
2431  SDValue InFlag = Chain.getValue(1);
2432
2433  // Create the CALLSEQ_END node.
2434  Chain = DAG.getCALLSEQ_END(Chain, NextStackOffsetVal,
2435                             DAG.getIntPtrConstant(0, true), InFlag);
2436  InFlag = Chain.getValue(1);
2437
2438  // Handle result values, copying them out of physregs into vregs that we
2439  // return.
2440  return LowerCallResult(Chain, InFlag, CallConv, IsVarArg,
2441                         Ins, DL, DAG, InVals, CLI.Callee.getNode(), CLI.RetTy);
2442}
2443
2444/// LowerCallResult - Lower the result values of a call into the
2445/// appropriate copies out of appropriate physical registers.
2446SDValue
2447MipsTargetLowering::LowerCallResult(SDValue Chain, SDValue InFlag,
2448                                    CallingConv::ID CallConv, bool IsVarArg,
2449                                    const SmallVectorImpl<ISD::InputArg> &Ins,
2450                                    DebugLoc DL, SelectionDAG &DAG,
2451                                    SmallVectorImpl<SDValue> &InVals,
2452                                    const SDNode *CallNode,
2453                                    const Type *RetTy) const {
2454  // Assign locations to each value returned by this call.
2455  SmallVector<CCValAssign, 16> RVLocs;
2456  CCState CCInfo(CallConv, IsVarArg, DAG.getMachineFunction(),
2457                 getTargetMachine(), RVLocs, *DAG.getContext());
2458  MipsCC MipsCCInfo(CallConv, IsO32, CCInfo);
2459
2460  MipsCCInfo.analyzeCallResult(Ins, getTargetMachine().Options.UseSoftFloat,
2461                               CallNode, RetTy);
2462
2463  // Copy all of the result registers out of their specified physreg.
2464  for (unsigned i = 0; i != RVLocs.size(); ++i) {
2465    SDValue Val = DAG.getCopyFromReg(Chain, DL, RVLocs[i].getLocReg(),
2466                                     RVLocs[i].getLocVT(), InFlag);
2467    Chain = Val.getValue(1);
2468    InFlag = Val.getValue(2);
2469
2470    if (RVLocs[i].getValVT() != RVLocs[i].getLocVT())
2471      Val = DAG.getNode(ISD::BITCAST, DL, RVLocs[i].getValVT(), Val);
2472
2473    InVals.push_back(Val);
2474  }
2475
2476  return Chain;
2477}
2478
2479//===----------------------------------------------------------------------===//
2480//             Formal Arguments Calling Convention Implementation
2481//===----------------------------------------------------------------------===//
2482/// LowerFormalArguments - transform physical registers into virtual registers
2483/// and generate load operations for arguments places on the stack.
2484SDValue
2485MipsTargetLowering::LowerFormalArguments(SDValue Chain,
2486                                         CallingConv::ID CallConv,
2487                                         bool IsVarArg,
2488                                      const SmallVectorImpl<ISD::InputArg> &Ins,
2489                                         DebugLoc DL, SelectionDAG &DAG,
2490                                         SmallVectorImpl<SDValue> &InVals)
2491                                          const {
2492  MachineFunction &MF = DAG.getMachineFunction();
2493  MachineFrameInfo *MFI = MF.getFrameInfo();
2494  MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
2495
2496  MipsFI->setVarArgsFrameIndex(0);
2497
2498  // Used with vargs to acumulate store chains.
2499  std::vector<SDValue> OutChains;
2500
2501  // Assign locations to all of the incoming arguments.
2502  SmallVector<CCValAssign, 16> ArgLocs;
2503  CCState CCInfo(CallConv, IsVarArg, DAG.getMachineFunction(),
2504                 getTargetMachine(), ArgLocs, *DAG.getContext());
2505  MipsCC MipsCCInfo(CallConv, IsO32, CCInfo);
2506  Function::const_arg_iterator FuncArg =
2507    DAG.getMachineFunction().getFunction()->arg_begin();
2508  bool UseSoftFloat = getTargetMachine().Options.UseSoftFloat;
2509
2510  MipsCCInfo.analyzeFormalArguments(Ins, UseSoftFloat, FuncArg);
2511  MipsFI->setFormalArgInfo(CCInfo.getNextStackOffset(),
2512                           MipsCCInfo.hasByValArg());
2513
2514  unsigned CurArgIdx = 0;
2515  MipsCC::byval_iterator ByValArg = MipsCCInfo.byval_begin();
2516
2517  for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
2518    CCValAssign &VA = ArgLocs[i];
2519    std::advance(FuncArg, Ins[i].OrigArgIndex - CurArgIdx);
2520    CurArgIdx = Ins[i].OrigArgIndex;
2521    EVT ValVT = VA.getValVT();
2522    ISD::ArgFlagsTy Flags = Ins[i].Flags;
2523    bool IsRegLoc = VA.isRegLoc();
2524
2525    if (Flags.isByVal()) {
2526      assert(Flags.getByValSize() &&
2527             "ByVal args of size 0 should have been ignored by front-end.");
2528      assert(ByValArg != MipsCCInfo.byval_end());
2529      copyByValRegs(Chain, DL, OutChains, DAG, Flags, InVals, &*FuncArg,
2530                    MipsCCInfo, *ByValArg);
2531      ++ByValArg;
2532      continue;
2533    }
2534
2535    // Arguments stored on registers
2536    if (IsRegLoc) {
2537      EVT RegVT = VA.getLocVT();
2538      unsigned ArgReg = VA.getLocReg();
2539      const TargetRegisterClass *RC;
2540
2541      if (RegVT == MVT::i32)
2542        RC = Subtarget->inMips16Mode()? &Mips::CPU16RegsRegClass :
2543                                        &Mips::CPURegsRegClass;
2544      else if (RegVT == MVT::i64)
2545        RC = &Mips::CPU64RegsRegClass;
2546      else if (RegVT == MVT::f32)
2547        RC = &Mips::FGR32RegClass;
2548      else if (RegVT == MVT::f64)
2549        RC = HasMips64 ? &Mips::FGR64RegClass : &Mips::AFGR64RegClass;
2550      else
2551        llvm_unreachable("RegVT not supported by FormalArguments Lowering");
2552
2553      // Transform the arguments stored on
2554      // physical registers into virtual ones
2555      unsigned Reg = addLiveIn(DAG.getMachineFunction(), ArgReg, RC);
2556      SDValue ArgValue = DAG.getCopyFromReg(Chain, DL, Reg, RegVT);
2557
2558      // If this is an 8 or 16-bit value, it has been passed promoted
2559      // to 32 bits.  Insert an assert[sz]ext to capture this, then
2560      // truncate to the right size.
2561      if (VA.getLocInfo() != CCValAssign::Full) {
2562        unsigned Opcode = 0;
2563        if (VA.getLocInfo() == CCValAssign::SExt)
2564          Opcode = ISD::AssertSext;
2565        else if (VA.getLocInfo() == CCValAssign::ZExt)
2566          Opcode = ISD::AssertZext;
2567        if (Opcode)
2568          ArgValue = DAG.getNode(Opcode, DL, RegVT, ArgValue,
2569                                 DAG.getValueType(ValVT));
2570        ArgValue = DAG.getNode(ISD::TRUNCATE, DL, ValVT, ArgValue);
2571      }
2572
2573      // Handle floating point arguments passed in integer registers and
2574      // long double arguments passed in floating point registers.
2575      if ((RegVT == MVT::i32 && ValVT == MVT::f32) ||
2576          (RegVT == MVT::i64 && ValVT == MVT::f64) ||
2577          (RegVT == MVT::f64 && ValVT == MVT::i64))
2578        ArgValue = DAG.getNode(ISD::BITCAST, DL, ValVT, ArgValue);
2579      else if (IsO32 && RegVT == MVT::i32 && ValVT == MVT::f64) {
2580        unsigned Reg2 = addLiveIn(DAG.getMachineFunction(),
2581                                  getNextIntArgReg(ArgReg), RC);
2582        SDValue ArgValue2 = DAG.getCopyFromReg(Chain, DL, Reg2, RegVT);
2583        if (!Subtarget->isLittle())
2584          std::swap(ArgValue, ArgValue2);
2585        ArgValue = DAG.getNode(MipsISD::BuildPairF64, DL, MVT::f64,
2586                               ArgValue, ArgValue2);
2587      }
2588
2589      InVals.push_back(ArgValue);
2590    } else { // VA.isRegLoc()
2591
2592      // sanity check
2593      assert(VA.isMemLoc());
2594
2595      // The stack pointer offset is relative to the caller stack frame.
2596      int FI = MFI->CreateFixedObject(ValVT.getSizeInBits()/8,
2597                                      VA.getLocMemOffset(), true);
2598
2599      // Create load nodes to retrieve arguments from the stack
2600      SDValue FIN = DAG.getFrameIndex(FI, getPointerTy());
2601      InVals.push_back(DAG.getLoad(ValVT, DL, Chain, FIN,
2602                                   MachinePointerInfo::getFixedStack(FI),
2603                                   false, false, false, 0));
2604    }
2605  }
2606
2607  // The mips ABIs for returning structs by value requires that we copy
2608  // the sret argument into $v0 for the return. Save the argument into
2609  // a virtual register so that we can access it from the return points.
2610  if (DAG.getMachineFunction().getFunction()->hasStructRetAttr()) {
2611    unsigned Reg = MipsFI->getSRetReturnReg();
2612    if (!Reg) {
2613      Reg = MF.getRegInfo().
2614        createVirtualRegister(getRegClassFor(IsN64 ? MVT::i64 : MVT::i32));
2615      MipsFI->setSRetReturnReg(Reg);
2616    }
2617    SDValue Copy = DAG.getCopyToReg(DAG.getEntryNode(), DL, Reg, InVals[0]);
2618    Chain = DAG.getNode(ISD::TokenFactor, DL, MVT::Other, Copy, Chain);
2619  }
2620
2621  if (IsVarArg)
2622    writeVarArgRegs(OutChains, MipsCCInfo, Chain, DL, DAG);
2623
2624  // All stores are grouped in one node to allow the matching between
2625  // the size of Ins and InVals. This only happens when on varg functions
2626  if (!OutChains.empty()) {
2627    OutChains.push_back(Chain);
2628    Chain = DAG.getNode(ISD::TokenFactor, DL, MVT::Other,
2629                        &OutChains[0], OutChains.size());
2630  }
2631
2632  return Chain;
2633}
2634
2635//===----------------------------------------------------------------------===//
2636//               Return Value Calling Convention Implementation
2637//===----------------------------------------------------------------------===//
2638
2639bool
2640MipsTargetLowering::CanLowerReturn(CallingConv::ID CallConv,
2641                                   MachineFunction &MF, bool IsVarArg,
2642                                   const SmallVectorImpl<ISD::OutputArg> &Outs,
2643                                   LLVMContext &Context) const {
2644  SmallVector<CCValAssign, 16> RVLocs;
2645  CCState CCInfo(CallConv, IsVarArg, MF, getTargetMachine(),
2646                 RVLocs, Context);
2647  return CCInfo.CheckReturn(Outs, RetCC_Mips);
2648}
2649
2650SDValue
2651MipsTargetLowering::LowerReturn(SDValue Chain,
2652                                CallingConv::ID CallConv, bool IsVarArg,
2653                                const SmallVectorImpl<ISD::OutputArg> &Outs,
2654                                const SmallVectorImpl<SDValue> &OutVals,
2655                                DebugLoc DL, SelectionDAG &DAG) const {
2656  // CCValAssign - represent the assignment of
2657  // the return value to a location
2658  SmallVector<CCValAssign, 16> RVLocs;
2659  MachineFunction &MF = DAG.getMachineFunction();
2660
2661  // CCState - Info about the registers and stack slot.
2662  CCState CCInfo(CallConv, IsVarArg, MF, getTargetMachine(), RVLocs,
2663                 *DAG.getContext());
2664  MipsCC MipsCCInfo(CallConv, IsO32, CCInfo);
2665
2666  // Analyze return values.
2667  MipsCCInfo.analyzeReturn(Outs, getTargetMachine().Options.UseSoftFloat,
2668                           MF.getFunction()->getReturnType());
2669
2670  SDValue Flag;
2671  SmallVector<SDValue, 4> RetOps(1, Chain);
2672
2673  // Copy the result values into the output registers.
2674  for (unsigned i = 0; i != RVLocs.size(); ++i) {
2675    SDValue Val = OutVals[i];
2676    CCValAssign &VA = RVLocs[i];
2677    assert(VA.isRegLoc() && "Can only return in registers!");
2678
2679    if (RVLocs[i].getValVT() != RVLocs[i].getLocVT())
2680      Val = DAG.getNode(ISD::BITCAST, DL, RVLocs[i].getLocVT(), Val);
2681
2682    Chain = DAG.getCopyToReg(Chain, DL, VA.getLocReg(), Val, Flag);
2683
2684    // Guarantee that all emitted copies are stuck together with flags.
2685    Flag = Chain.getValue(1);
2686    RetOps.push_back(DAG.getRegister(VA.getLocReg(), VA.getLocVT()));
2687  }
2688
2689  // The mips ABIs for returning structs by value requires that we copy
2690  // the sret argument into $v0 for the return. We saved the argument into
2691  // a virtual register in the entry block, so now we copy the value out
2692  // and into $v0.
2693  if (MF.getFunction()->hasStructRetAttr()) {
2694    MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
2695    unsigned Reg = MipsFI->getSRetReturnReg();
2696
2697    if (!Reg)
2698      llvm_unreachable("sret virtual register not created in the entry block");
2699    SDValue Val = DAG.getCopyFromReg(Chain, DL, Reg, getPointerTy());
2700    unsigned V0 = IsN64 ? Mips::V0_64 : Mips::V0;
2701
2702    Chain = DAG.getCopyToReg(Chain, DL, V0, Val, Flag);
2703    Flag = Chain.getValue(1);
2704    RetOps.push_back(DAG.getRegister(V0, getPointerTy()));
2705  }
2706
2707  RetOps[0] = Chain;  // Update chain.
2708
2709  // Add the flag if we have it.
2710  if (Flag.getNode())
2711    RetOps.push_back(Flag);
2712
2713  // Return on Mips is always a "jr $ra"
2714  return DAG.getNode(MipsISD::Ret, DL, MVT::Other, &RetOps[0], RetOps.size());
2715}
2716
2717//===----------------------------------------------------------------------===//
2718//                           Mips Inline Assembly Support
2719//===----------------------------------------------------------------------===//
2720
2721/// getConstraintType - Given a constraint letter, return the type of
2722/// constraint it is for this target.
2723MipsTargetLowering::ConstraintType MipsTargetLowering::
2724getConstraintType(const std::string &Constraint) const
2725{
2726  // Mips specific constrainy
2727  // GCC config/mips/constraints.md
2728  //
2729  // 'd' : An address register. Equivalent to r
2730  //       unless generating MIPS16 code.
2731  // 'y' : Equivalent to r; retained for
2732  //       backwards compatibility.
2733  // 'c' : A register suitable for use in an indirect
2734  //       jump. This will always be $25 for -mabicalls.
2735  // 'l' : The lo register. 1 word storage.
2736  // 'x' : The hilo register pair. Double word storage.
2737  if (Constraint.size() == 1) {
2738    switch (Constraint[0]) {
2739      default : break;
2740      case 'd':
2741      case 'y':
2742      case 'f':
2743      case 'c':
2744      case 'l':
2745      case 'x':
2746        return C_RegisterClass;
2747      case 'R':
2748        return C_Memory;
2749    }
2750  }
2751  return TargetLowering::getConstraintType(Constraint);
2752}
2753
2754/// Examine constraint type and operand type and determine a weight value.
2755/// This object must already have been set up with the operand type
2756/// and the current alternative constraint selected.
2757TargetLowering::ConstraintWeight
2758MipsTargetLowering::getSingleConstraintMatchWeight(
2759    AsmOperandInfo &info, const char *constraint) const {
2760  ConstraintWeight weight = CW_Invalid;
2761  Value *CallOperandVal = info.CallOperandVal;
2762    // If we don't have a value, we can't do a match,
2763    // but allow it at the lowest weight.
2764  if (CallOperandVal == NULL)
2765    return CW_Default;
2766  Type *type = CallOperandVal->getType();
2767  // Look at the constraint type.
2768  switch (*constraint) {
2769  default:
2770    weight = TargetLowering::getSingleConstraintMatchWeight(info, constraint);
2771    break;
2772  case 'd':
2773  case 'y':
2774    if (type->isIntegerTy())
2775      weight = CW_Register;
2776    break;
2777  case 'f':
2778    if (type->isFloatTy())
2779      weight = CW_Register;
2780    break;
2781  case 'c': // $25 for indirect jumps
2782  case 'l': // lo register
2783  case 'x': // hilo register pair
2784      if (type->isIntegerTy())
2785      weight = CW_SpecificReg;
2786      break;
2787  case 'I': // signed 16 bit immediate
2788  case 'J': // integer zero
2789  case 'K': // unsigned 16 bit immediate
2790  case 'L': // signed 32 bit immediate where lower 16 bits are 0
2791  case 'N': // immediate in the range of -65535 to -1 (inclusive)
2792  case 'O': // signed 15 bit immediate (+- 16383)
2793  case 'P': // immediate in the range of 65535 to 1 (inclusive)
2794    if (isa<ConstantInt>(CallOperandVal))
2795      weight = CW_Constant;
2796    break;
2797  case 'R':
2798    weight = CW_Memory;
2799    break;
2800  }
2801  return weight;
2802}
2803
2804/// Given a register class constraint, like 'r', if this corresponds directly
2805/// to an LLVM register class, return a register of 0 and the register class
2806/// pointer.
2807std::pair<unsigned, const TargetRegisterClass*> MipsTargetLowering::
2808getRegForInlineAsmConstraint(const std::string &Constraint, EVT VT) const
2809{
2810  if (Constraint.size() == 1) {
2811    switch (Constraint[0]) {
2812    case 'd': // Address register. Same as 'r' unless generating MIPS16 code.
2813    case 'y': // Same as 'r'. Exists for compatibility.
2814    case 'r':
2815      if (VT == MVT::i32 || VT == MVT::i16 || VT == MVT::i8) {
2816        if (Subtarget->inMips16Mode())
2817          return std::make_pair(0U, &Mips::CPU16RegsRegClass);
2818        return std::make_pair(0U, &Mips::CPURegsRegClass);
2819      }
2820      if (VT == MVT::i64 && !HasMips64)
2821        return std::make_pair(0U, &Mips::CPURegsRegClass);
2822      if (VT == MVT::i64 && HasMips64)
2823        return std::make_pair(0U, &Mips::CPU64RegsRegClass);
2824      // This will generate an error message
2825      return std::make_pair(0u, static_cast<const TargetRegisterClass*>(0));
2826    case 'f':
2827      if (VT == MVT::f32)
2828        return std::make_pair(0U, &Mips::FGR32RegClass);
2829      if ((VT == MVT::f64) && (!Subtarget->isSingleFloat())) {
2830        if (Subtarget->isFP64bit())
2831          return std::make_pair(0U, &Mips::FGR64RegClass);
2832        return std::make_pair(0U, &Mips::AFGR64RegClass);
2833      }
2834      break;
2835    case 'c': // register suitable for indirect jump
2836      if (VT == MVT::i32)
2837        return std::make_pair((unsigned)Mips::T9, &Mips::CPURegsRegClass);
2838      assert(VT == MVT::i64 && "Unexpected type.");
2839      return std::make_pair((unsigned)Mips::T9_64, &Mips::CPU64RegsRegClass);
2840    case 'l': // register suitable for indirect jump
2841      if (VT == MVT::i32)
2842        return std::make_pair((unsigned)Mips::LO, &Mips::HILORegClass);
2843      return std::make_pair((unsigned)Mips::LO64, &Mips::HILO64RegClass);
2844    case 'x': // register suitable for indirect jump
2845      // Fixme: Not triggering the use of both hi and low
2846      // This will generate an error message
2847      return std::make_pair(0u, static_cast<const TargetRegisterClass*>(0));
2848    }
2849  }
2850  return TargetLowering::getRegForInlineAsmConstraint(Constraint, VT);
2851}
2852
2853/// LowerAsmOperandForConstraint - Lower the specified operand into the Ops
2854/// vector.  If it is invalid, don't add anything to Ops.
2855void MipsTargetLowering::LowerAsmOperandForConstraint(SDValue Op,
2856                                                     std::string &Constraint,
2857                                                     std::vector<SDValue>&Ops,
2858                                                     SelectionDAG &DAG) const {
2859  SDValue Result(0, 0);
2860
2861  // Only support length 1 constraints for now.
2862  if (Constraint.length() > 1) return;
2863
2864  char ConstraintLetter = Constraint[0];
2865  switch (ConstraintLetter) {
2866  default: break; // This will fall through to the generic implementation
2867  case 'I': // Signed 16 bit constant
2868    // If this fails, the parent routine will give an error
2869    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
2870      EVT Type = Op.getValueType();
2871      int64_t Val = C->getSExtValue();
2872      if (isInt<16>(Val)) {
2873        Result = DAG.getTargetConstant(Val, Type);
2874        break;
2875      }
2876    }
2877    return;
2878  case 'J': // integer zero
2879    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
2880      EVT Type = Op.getValueType();
2881      int64_t Val = C->getZExtValue();
2882      if (Val == 0) {
2883        Result = DAG.getTargetConstant(0, Type);
2884        break;
2885      }
2886    }
2887    return;
2888  case 'K': // unsigned 16 bit immediate
2889    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
2890      EVT Type = Op.getValueType();
2891      uint64_t Val = (uint64_t)C->getZExtValue();
2892      if (isUInt<16>(Val)) {
2893        Result = DAG.getTargetConstant(Val, Type);
2894        break;
2895      }
2896    }
2897    return;
2898  case 'L': // signed 32 bit immediate where lower 16 bits are 0
2899    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
2900      EVT Type = Op.getValueType();
2901      int64_t Val = C->getSExtValue();
2902      if ((isInt<32>(Val)) && ((Val & 0xffff) == 0)){
2903        Result = DAG.getTargetConstant(Val, Type);
2904        break;
2905      }
2906    }
2907    return;
2908  case 'N': // immediate in the range of -65535 to -1 (inclusive)
2909    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
2910      EVT Type = Op.getValueType();
2911      int64_t Val = C->getSExtValue();
2912      if ((Val >= -65535) && (Val <= -1)) {
2913        Result = DAG.getTargetConstant(Val, Type);
2914        break;
2915      }
2916    }
2917    return;
2918  case 'O': // signed 15 bit immediate
2919    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
2920      EVT Type = Op.getValueType();
2921      int64_t Val = C->getSExtValue();
2922      if ((isInt<15>(Val))) {
2923        Result = DAG.getTargetConstant(Val, Type);
2924        break;
2925      }
2926    }
2927    return;
2928  case 'P': // immediate in the range of 1 to 65535 (inclusive)
2929    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
2930      EVT Type = Op.getValueType();
2931      int64_t Val = C->getSExtValue();
2932      if ((Val <= 65535) && (Val >= 1)) {
2933        Result = DAG.getTargetConstant(Val, Type);
2934        break;
2935      }
2936    }
2937    return;
2938  }
2939
2940  if (Result.getNode()) {
2941    Ops.push_back(Result);
2942    return;
2943  }
2944
2945  TargetLowering::LowerAsmOperandForConstraint(Op, Constraint, Ops, DAG);
2946}
2947
2948bool
2949MipsTargetLowering::isLegalAddressingMode(const AddrMode &AM, Type *Ty) const {
2950  // No global is ever allowed as a base.
2951  if (AM.BaseGV)
2952    return false;
2953
2954  switch (AM.Scale) {
2955  case 0: // "r+i" or just "i", depending on HasBaseReg.
2956    break;
2957  case 1:
2958    if (!AM.HasBaseReg) // allow "r+i".
2959      break;
2960    return false; // disallow "r+r" or "r+r+i".
2961  default:
2962    return false;
2963  }
2964
2965  return true;
2966}
2967
2968bool
2969MipsTargetLowering::isOffsetFoldingLegal(const GlobalAddressSDNode *GA) const {
2970  // The Mips target isn't yet aware of offsets.
2971  return false;
2972}
2973
2974EVT MipsTargetLowering::getOptimalMemOpType(uint64_t Size, unsigned DstAlign,
2975                                            unsigned SrcAlign,
2976                                            bool IsMemset, bool ZeroMemset,
2977                                            bool MemcpyStrSrc,
2978                                            MachineFunction &MF) const {
2979  if (Subtarget->hasMips64())
2980    return MVT::i64;
2981
2982  return MVT::i32;
2983}
2984
2985bool MipsTargetLowering::isFPImmLegal(const APFloat &Imm, EVT VT) const {
2986  if (VT != MVT::f32 && VT != MVT::f64)
2987    return false;
2988  if (Imm.isNegZero())
2989    return false;
2990  return Imm.isZero();
2991}
2992
2993unsigned MipsTargetLowering::getJumpTableEncoding() const {
2994  if (IsN64)
2995    return MachineJumpTableInfo::EK_GPRel64BlockAddress;
2996
2997  return TargetLowering::getJumpTableEncoding();
2998}
2999
3000/// This function returns true if CallSym is a long double emulation routine.
3001static bool isF128SoftLibCall(const char *CallSym) {
3002  const char *const LibCalls[] =
3003    {"__addtf3", "__divtf3", "__eqtf2", "__extenddftf2", "__extendsftf2",
3004     "__fixtfdi", "__fixtfsi", "__fixtfti", "__fixunstfdi", "__fixunstfsi",
3005     "__fixunstfti", "__floatditf", "__floatsitf", "__floattitf",
3006     "__floatunditf", "__floatunsitf", "__floatuntitf", "__getf2", "__gttf2",
3007     "__letf2", "__lttf2", "__multf3", "__netf2", "__powitf2", "__subtf3",
3008     "__trunctfdf2", "__trunctfsf2", "__unordtf2",
3009     "ceill", "copysignl", "cosl", "exp2l", "expl", "floorl", "fmal", "fmodl",
3010     "log10l", "log2l", "logl", "nearbyintl", "powl", "rintl", "sinl", "sqrtl",
3011     "truncl"};
3012
3013  const char * const *End = LibCalls + array_lengthof(LibCalls);
3014
3015  // Check that LibCalls is sorted alphabetically.
3016  MipsTargetLowering::LTStr Comp;
3017
3018#ifndef NDEBUG
3019  for (const char * const *I = LibCalls; I < End - 1; ++I)
3020    assert(Comp(*I, *(I + 1)));
3021#endif
3022
3023  return std::binary_search(LibCalls, End, CallSym, Comp);
3024}
3025
3026/// This function returns true if Ty is fp128 or i128 which was originally a
3027/// fp128.
3028static bool originalTypeIsF128(const Type *Ty, const SDNode *CallNode) {
3029  if (Ty->isFP128Ty())
3030    return true;
3031
3032  const ExternalSymbolSDNode *ES =
3033    dyn_cast_or_null<const ExternalSymbolSDNode>(CallNode);
3034
3035  // If the Ty is i128 and the function being called is a long double emulation
3036  // routine, then the original type is f128.
3037  return (ES && Ty->isIntegerTy(128) && isF128SoftLibCall(ES->getSymbol()));
3038}
3039
3040MipsTargetLowering::MipsCC::MipsCC(CallingConv::ID CC, bool IsO32_,
3041                                   CCState &Info)
3042  : CCInfo(Info), CallConv(CC), IsO32(IsO32_) {
3043  // Pre-allocate reserved argument area.
3044  CCInfo.AllocateStack(reservedArgArea(), 1);
3045}
3046
3047void MipsTargetLowering::MipsCC::
3048analyzeCallOperands(const SmallVectorImpl<ISD::OutputArg> &Args,
3049                    bool IsVarArg, bool IsSoftFloat, const SDNode *CallNode,
3050                    std::vector<ArgListEntry> &FuncArgs) {
3051  assert((CallConv != CallingConv::Fast || !IsVarArg) &&
3052         "CallingConv::Fast shouldn't be used for vararg functions.");
3053
3054  unsigned NumOpnds = Args.size();
3055  llvm::CCAssignFn *FixedFn = fixedArgFn(), *VarFn = varArgFn();
3056
3057  for (unsigned I = 0; I != NumOpnds; ++I) {
3058    MVT ArgVT = Args[I].VT;
3059    ISD::ArgFlagsTy ArgFlags = Args[I].Flags;
3060    bool R;
3061
3062    if (ArgFlags.isByVal()) {
3063      handleByValArg(I, ArgVT, ArgVT, CCValAssign::Full, ArgFlags);
3064      continue;
3065    }
3066
3067    if (IsVarArg && !Args[I].IsFixed)
3068      R = VarFn(I, ArgVT, ArgVT, CCValAssign::Full, ArgFlags, CCInfo);
3069    else {
3070      MVT RegVT = getRegVT(ArgVT, FuncArgs[Args[I].OrigArgIndex].Ty, CallNode,
3071                           IsSoftFloat);
3072      R = FixedFn(I, ArgVT, RegVT, CCValAssign::Full, ArgFlags, CCInfo);
3073    }
3074
3075    if (R) {
3076#ifndef NDEBUG
3077      dbgs() << "Call operand #" << I << " has unhandled type "
3078             << EVT(ArgVT).getEVTString();
3079#endif
3080      llvm_unreachable(0);
3081    }
3082  }
3083}
3084
3085void MipsTargetLowering::MipsCC::
3086analyzeFormalArguments(const SmallVectorImpl<ISD::InputArg> &Args,
3087                       bool IsSoftFloat, Function::const_arg_iterator FuncArg) {
3088  unsigned NumArgs = Args.size();
3089  llvm::CCAssignFn *FixedFn = fixedArgFn();
3090  unsigned CurArgIdx = 0;
3091
3092  for (unsigned I = 0; I != NumArgs; ++I) {
3093    MVT ArgVT = Args[I].VT;
3094    ISD::ArgFlagsTy ArgFlags = Args[I].Flags;
3095    std::advance(FuncArg, Args[I].OrigArgIndex - CurArgIdx);
3096    CurArgIdx = Args[I].OrigArgIndex;
3097
3098    if (ArgFlags.isByVal()) {
3099      handleByValArg(I, ArgVT, ArgVT, CCValAssign::Full, ArgFlags);
3100      continue;
3101    }
3102
3103    MVT RegVT = getRegVT(ArgVT, FuncArg->getType(), 0, IsSoftFloat);
3104
3105    if (!FixedFn(I, ArgVT, RegVT, CCValAssign::Full, ArgFlags, CCInfo))
3106      continue;
3107
3108#ifndef NDEBUG
3109    dbgs() << "Formal Arg #" << I << " has unhandled type "
3110           << EVT(ArgVT).getEVTString();
3111#endif
3112    llvm_unreachable(0);
3113  }
3114}
3115
3116template<typename Ty>
3117void MipsTargetLowering::MipsCC::
3118analyzeReturn(const SmallVectorImpl<Ty> &RetVals, bool IsSoftFloat,
3119              const SDNode *CallNode, const Type *RetTy) const {
3120  CCAssignFn *Fn;
3121
3122  if (IsSoftFloat && originalTypeIsF128(RetTy, CallNode))
3123    Fn = RetCC_F128Soft;
3124  else
3125    Fn = RetCC_Mips;
3126
3127  for (unsigned I = 0, E = RetVals.size(); I < E; ++I) {
3128    MVT VT = RetVals[I].VT;
3129    ISD::ArgFlagsTy Flags = RetVals[I].Flags;
3130    MVT RegVT = this->getRegVT(VT, RetTy, CallNode, IsSoftFloat);
3131
3132    if (Fn(I, VT, RegVT, CCValAssign::Full, Flags, this->CCInfo)) {
3133#ifndef NDEBUG
3134      dbgs() << "Call result #" << I << " has unhandled type "
3135             << EVT(VT).getEVTString() << '\n';
3136#endif
3137      llvm_unreachable(0);
3138    }
3139  }
3140}
3141
3142void MipsTargetLowering::MipsCC::
3143analyzeCallResult(const SmallVectorImpl<ISD::InputArg> &Ins, bool IsSoftFloat,
3144                  const SDNode *CallNode, const Type *RetTy) const {
3145  analyzeReturn(Ins, IsSoftFloat, CallNode, RetTy);
3146}
3147
3148void MipsTargetLowering::MipsCC::
3149analyzeReturn(const SmallVectorImpl<ISD::OutputArg> &Outs, bool IsSoftFloat,
3150              const Type *RetTy) const {
3151  analyzeReturn(Outs, IsSoftFloat, 0, RetTy);
3152}
3153
3154void
3155MipsTargetLowering::MipsCC::handleByValArg(unsigned ValNo, MVT ValVT,
3156                                           MVT LocVT,
3157                                           CCValAssign::LocInfo LocInfo,
3158                                           ISD::ArgFlagsTy ArgFlags) {
3159  assert(ArgFlags.getByValSize() && "Byval argument's size shouldn't be 0.");
3160
3161  struct ByValArgInfo ByVal;
3162  unsigned RegSize = regSize();
3163  unsigned ByValSize = RoundUpToAlignment(ArgFlags.getByValSize(), RegSize);
3164  unsigned Align = std::min(std::max(ArgFlags.getByValAlign(), RegSize),
3165                            RegSize * 2);
3166
3167  if (useRegsForByval())
3168    allocateRegs(ByVal, ByValSize, Align);
3169
3170  // Allocate space on caller's stack.
3171  ByVal.Address = CCInfo.AllocateStack(ByValSize - RegSize * ByVal.NumRegs,
3172                                       Align);
3173  CCInfo.addLoc(CCValAssign::getMem(ValNo, ValVT, ByVal.Address, LocVT,
3174                                    LocInfo));
3175  ByValArgs.push_back(ByVal);
3176}
3177
3178unsigned MipsTargetLowering::MipsCC::numIntArgRegs() const {
3179  return IsO32 ? array_lengthof(O32IntRegs) : array_lengthof(Mips64IntRegs);
3180}
3181
3182unsigned MipsTargetLowering::MipsCC::reservedArgArea() const {
3183  return (IsO32 && (CallConv != CallingConv::Fast)) ? 16 : 0;
3184}
3185
3186const uint16_t *MipsTargetLowering::MipsCC::intArgRegs() const {
3187  return IsO32 ? O32IntRegs : Mips64IntRegs;
3188}
3189
3190llvm::CCAssignFn *MipsTargetLowering::MipsCC::fixedArgFn() const {
3191  if (CallConv == CallingConv::Fast)
3192    return CC_Mips_FastCC;
3193
3194  return IsO32 ? CC_MipsO32 : CC_MipsN;
3195}
3196
3197llvm::CCAssignFn *MipsTargetLowering::MipsCC::varArgFn() const {
3198  return IsO32 ? CC_MipsO32 : CC_MipsN_VarArg;
3199}
3200
3201const uint16_t *MipsTargetLowering::MipsCC::shadowRegs() const {
3202  return IsO32 ? O32IntRegs : Mips64DPRegs;
3203}
3204
3205void MipsTargetLowering::MipsCC::allocateRegs(ByValArgInfo &ByVal,
3206                                              unsigned ByValSize,
3207                                              unsigned Align) {
3208  unsigned RegSize = regSize(), NumIntArgRegs = numIntArgRegs();
3209  const uint16_t *IntArgRegs = intArgRegs(), *ShadowRegs = shadowRegs();
3210  assert(!(ByValSize % RegSize) && !(Align % RegSize) &&
3211         "Byval argument's size and alignment should be a multiple of"
3212         "RegSize.");
3213
3214  ByVal.FirstIdx = CCInfo.getFirstUnallocated(IntArgRegs, NumIntArgRegs);
3215
3216  // If Align > RegSize, the first arg register must be even.
3217  if ((Align > RegSize) && (ByVal.FirstIdx % 2)) {
3218    CCInfo.AllocateReg(IntArgRegs[ByVal.FirstIdx], ShadowRegs[ByVal.FirstIdx]);
3219    ++ByVal.FirstIdx;
3220  }
3221
3222  // Mark the registers allocated.
3223  for (unsigned I = ByVal.FirstIdx; ByValSize && (I < NumIntArgRegs);
3224       ByValSize -= RegSize, ++I, ++ByVal.NumRegs)
3225    CCInfo.AllocateReg(IntArgRegs[I], ShadowRegs[I]);
3226}
3227
3228MVT MipsTargetLowering::MipsCC::getRegVT(MVT VT, const Type *OrigTy,
3229                                         const SDNode *CallNode,
3230                                         bool IsSoftFloat) const {
3231  if (IsSoftFloat || IsO32)
3232    return VT;
3233
3234  // Check if the original type was fp128.
3235  if (originalTypeIsF128(OrigTy, CallNode)) {
3236    assert(VT == MVT::i64);
3237    return MVT::f64;
3238  }
3239
3240  return VT;
3241}
3242
3243void MipsTargetLowering::
3244copyByValRegs(SDValue Chain, DebugLoc DL, std::vector<SDValue> &OutChains,
3245              SelectionDAG &DAG, const ISD::ArgFlagsTy &Flags,
3246              SmallVectorImpl<SDValue> &InVals, const Argument *FuncArg,
3247              const MipsCC &CC, const ByValArgInfo &ByVal) const {
3248  MachineFunction &MF = DAG.getMachineFunction();
3249  MachineFrameInfo *MFI = MF.getFrameInfo();
3250  unsigned RegAreaSize = ByVal.NumRegs * CC.regSize();
3251  unsigned FrameObjSize = std::max(Flags.getByValSize(), RegAreaSize);
3252  int FrameObjOffset;
3253
3254  if (RegAreaSize)
3255    FrameObjOffset = (int)CC.reservedArgArea() -
3256      (int)((CC.numIntArgRegs() - ByVal.FirstIdx) * CC.regSize());
3257  else
3258    FrameObjOffset = ByVal.Address;
3259
3260  // Create frame object.
3261  EVT PtrTy = getPointerTy();
3262  int FI = MFI->CreateFixedObject(FrameObjSize, FrameObjOffset, true);
3263  SDValue FIN = DAG.getFrameIndex(FI, PtrTy);
3264  InVals.push_back(FIN);
3265
3266  if (!ByVal.NumRegs)
3267    return;
3268
3269  // Copy arg registers.
3270  MVT RegTy = MVT::getIntegerVT(CC.regSize() * 8);
3271  const TargetRegisterClass *RC = getRegClassFor(RegTy);
3272
3273  for (unsigned I = 0; I < ByVal.NumRegs; ++I) {
3274    unsigned ArgReg = CC.intArgRegs()[ByVal.FirstIdx + I];
3275    unsigned VReg = addLiveIn(MF, ArgReg, RC);
3276    unsigned Offset = I * CC.regSize();
3277    SDValue StorePtr = DAG.getNode(ISD::ADD, DL, PtrTy, FIN,
3278                                   DAG.getConstant(Offset, PtrTy));
3279    SDValue Store = DAG.getStore(Chain, DL, DAG.getRegister(VReg, RegTy),
3280                                 StorePtr, MachinePointerInfo(FuncArg, Offset),
3281                                 false, false, 0);
3282    OutChains.push_back(Store);
3283  }
3284}
3285
3286// Copy byVal arg to registers and stack.
3287void MipsTargetLowering::
3288passByValArg(SDValue Chain, DebugLoc DL,
3289             std::deque< std::pair<unsigned, SDValue> > &RegsToPass,
3290             SmallVector<SDValue, 8> &MemOpChains, SDValue StackPtr,
3291             MachineFrameInfo *MFI, SelectionDAG &DAG, SDValue Arg,
3292             const MipsCC &CC, const ByValArgInfo &ByVal,
3293             const ISD::ArgFlagsTy &Flags, bool isLittle) const {
3294  unsigned ByValSize = Flags.getByValSize();
3295  unsigned Offset = 0; // Offset in # of bytes from the beginning of struct.
3296  unsigned RegSize = CC.regSize();
3297  unsigned Alignment = std::min(Flags.getByValAlign(), RegSize);
3298  EVT PtrTy = getPointerTy(), RegTy = MVT::getIntegerVT(RegSize * 8);
3299
3300  if (ByVal.NumRegs) {
3301    const uint16_t *ArgRegs = CC.intArgRegs();
3302    bool LeftoverBytes = (ByVal.NumRegs * RegSize > ByValSize);
3303    unsigned I = 0;
3304
3305    // Copy words to registers.
3306    for (; I < ByVal.NumRegs - LeftoverBytes; ++I, Offset += RegSize) {
3307      SDValue LoadPtr = DAG.getNode(ISD::ADD, DL, PtrTy, Arg,
3308                                    DAG.getConstant(Offset, PtrTy));
3309      SDValue LoadVal = DAG.getLoad(RegTy, DL, Chain, LoadPtr,
3310                                    MachinePointerInfo(), false, false, false,
3311                                    Alignment);
3312      MemOpChains.push_back(LoadVal.getValue(1));
3313      unsigned ArgReg = ArgRegs[ByVal.FirstIdx + I];
3314      RegsToPass.push_back(std::make_pair(ArgReg, LoadVal));
3315    }
3316
3317    // Return if the struct has been fully copied.
3318    if (ByValSize == Offset)
3319      return;
3320
3321    // Copy the remainder of the byval argument with sub-word loads and shifts.
3322    if (LeftoverBytes) {
3323      assert((ByValSize > Offset) && (ByValSize < Offset + RegSize) &&
3324             "Size of the remainder should be smaller than RegSize.");
3325      SDValue Val;
3326
3327      for (unsigned LoadSize = RegSize / 2, TotalSizeLoaded = 0;
3328           Offset < ByValSize; LoadSize /= 2) {
3329        unsigned RemSize = ByValSize - Offset;
3330
3331        if (RemSize < LoadSize)
3332          continue;
3333
3334        // Load subword.
3335        SDValue LoadPtr = DAG.getNode(ISD::ADD, DL, PtrTy, Arg,
3336                                      DAG.getConstant(Offset, PtrTy));
3337        SDValue LoadVal =
3338          DAG.getExtLoad(ISD::ZEXTLOAD, DL, RegTy, Chain, LoadPtr,
3339                         MachinePointerInfo(), MVT::getIntegerVT(LoadSize * 8),
3340                         false, false, Alignment);
3341        MemOpChains.push_back(LoadVal.getValue(1));
3342
3343        // Shift the loaded value.
3344        unsigned Shamt;
3345
3346        if (isLittle)
3347          Shamt = TotalSizeLoaded;
3348        else
3349          Shamt = (RegSize - (TotalSizeLoaded + LoadSize)) * 8;
3350
3351        SDValue Shift = DAG.getNode(ISD::SHL, DL, RegTy, LoadVal,
3352                                    DAG.getConstant(Shamt, MVT::i32));
3353
3354        if (Val.getNode())
3355          Val = DAG.getNode(ISD::OR, DL, RegTy, Val, Shift);
3356        else
3357          Val = Shift;
3358
3359        Offset += LoadSize;
3360        TotalSizeLoaded += LoadSize;
3361        Alignment = std::min(Alignment, LoadSize);
3362      }
3363
3364      unsigned ArgReg = ArgRegs[ByVal.FirstIdx + I];
3365      RegsToPass.push_back(std::make_pair(ArgReg, Val));
3366      return;
3367    }
3368  }
3369
3370  // Copy remainder of byval arg to it with memcpy.
3371  unsigned MemCpySize = ByValSize - Offset;
3372  SDValue Src = DAG.getNode(ISD::ADD, DL, PtrTy, Arg,
3373                            DAG.getConstant(Offset, PtrTy));
3374  SDValue Dst = DAG.getNode(ISD::ADD, DL, PtrTy, StackPtr,
3375                            DAG.getIntPtrConstant(ByVal.Address));
3376  Chain = DAG.getMemcpy(Chain, DL, Dst, Src,
3377                        DAG.getConstant(MemCpySize, PtrTy), Alignment,
3378                        /*isVolatile=*/false, /*AlwaysInline=*/false,
3379                        MachinePointerInfo(0), MachinePointerInfo(0));
3380  MemOpChains.push_back(Chain);
3381}
3382
3383void
3384MipsTargetLowering::writeVarArgRegs(std::vector<SDValue> &OutChains,
3385                                    const MipsCC &CC, SDValue Chain,
3386                                    DebugLoc DL, SelectionDAG &DAG) const {
3387  unsigned NumRegs = CC.numIntArgRegs();
3388  const uint16_t *ArgRegs = CC.intArgRegs();
3389  const CCState &CCInfo = CC.getCCInfo();
3390  unsigned Idx = CCInfo.getFirstUnallocated(ArgRegs, NumRegs);
3391  unsigned RegSize = CC.regSize();
3392  MVT RegTy = MVT::getIntegerVT(RegSize * 8);
3393  const TargetRegisterClass *RC = getRegClassFor(RegTy);
3394  MachineFunction &MF = DAG.getMachineFunction();
3395  MachineFrameInfo *MFI = MF.getFrameInfo();
3396  MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
3397
3398  // Offset of the first variable argument from stack pointer.
3399  int VaArgOffset;
3400
3401  if (NumRegs == Idx)
3402    VaArgOffset = RoundUpToAlignment(CCInfo.getNextStackOffset(), RegSize);
3403  else
3404    VaArgOffset =
3405      (int)CC.reservedArgArea() - (int)(RegSize * (NumRegs - Idx));
3406
3407  // Record the frame index of the first variable argument
3408  // which is a value necessary to VASTART.
3409  int FI = MFI->CreateFixedObject(RegSize, VaArgOffset, true);
3410  MipsFI->setVarArgsFrameIndex(FI);
3411
3412  // Copy the integer registers that have not been used for argument passing
3413  // to the argument register save area. For O32, the save area is allocated
3414  // in the caller's stack frame, while for N32/64, it is allocated in the
3415  // callee's stack frame.
3416  for (unsigned I = Idx; I < NumRegs; ++I, VaArgOffset += RegSize) {
3417    unsigned Reg = addLiveIn(MF, ArgRegs[I], RC);
3418    SDValue ArgValue = DAG.getCopyFromReg(Chain, DL, Reg, RegTy);
3419    FI = MFI->CreateFixedObject(RegSize, VaArgOffset, true);
3420    SDValue PtrOff = DAG.getFrameIndex(FI, getPointerTy());
3421    SDValue Store = DAG.getStore(Chain, DL, ArgValue, PtrOff,
3422                                 MachinePointerInfo(), false, false, 0);
3423    cast<StoreSDNode>(Store.getNode())->getMemOperand()->setValue(0);
3424    OutChains.push_back(Store);
3425  }
3426}
3427