MipsISelLowering.cpp revision ed23fa8e55f5a58741c20c601410c2822d00f066
1//===-- MipsISelLowering.cpp - Mips DAG Lowering Implementation -----------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file defines the interfaces that Mips uses to lower LLVM code into a
11// selection DAG.
12//
13//===----------------------------------------------------------------------===//
14
15#define DEBUG_TYPE "mips-lower"
16#include "MipsISelLowering.h"
17#include "InstPrinter/MipsInstPrinter.h"
18#include "MCTargetDesc/MipsBaseInfo.h"
19#include "MipsMachineFunction.h"
20#include "MipsSubtarget.h"
21#include "MipsTargetMachine.h"
22#include "MipsTargetObjectFile.h"
23#include "llvm/ADT/Statistic.h"
24#include "llvm/CallingConv.h"
25#include "llvm/CodeGen/CallingConvLower.h"
26#include "llvm/CodeGen/MachineFrameInfo.h"
27#include "llvm/CodeGen/MachineFunction.h"
28#include "llvm/CodeGen/MachineInstrBuilder.h"
29#include "llvm/CodeGen/MachineRegisterInfo.h"
30#include "llvm/CodeGen/SelectionDAGISel.h"
31#include "llvm/CodeGen/ValueTypes.h"
32#include "llvm/DerivedTypes.h"
33#include "llvm/Function.h"
34#include "llvm/GlobalVariable.h"
35#include "llvm/Intrinsics.h"
36#include "llvm/Support/CommandLine.h"
37#include "llvm/Support/Debug.h"
38#include "llvm/Support/ErrorHandling.h"
39#include "llvm/Support/raw_ostream.h"
40
41using namespace llvm;
42
43STATISTIC(NumTailCalls, "Number of tail calls");
44
45static cl::opt<bool>
46EnableMipsTailCalls("enable-mips-tail-calls", cl::Hidden,
47                    cl::desc("MIPS: Enable tail calls."), cl::init(false));
48
49static cl::opt<bool>
50LargeGOT("mxgot", cl::Hidden,
51         cl::desc("MIPS: Enable GOT larger than 64k."), cl::init(false));
52
53static cl::opt<bool>
54Mips16HardFloat("mips16-hard-float", cl::NotHidden,
55                cl::desc("MIPS: mips16 hard float enable."),
56                cl::init(false));
57
58
59
60static const uint16_t O32IntRegs[4] = {
61  Mips::A0, Mips::A1, Mips::A2, Mips::A3
62};
63
64static const uint16_t Mips64IntRegs[8] = {
65  Mips::A0_64, Mips::A1_64, Mips::A2_64, Mips::A3_64,
66  Mips::T0_64, Mips::T1_64, Mips::T2_64, Mips::T3_64
67};
68
69static const uint16_t Mips64DPRegs[8] = {
70  Mips::D12_64, Mips::D13_64, Mips::D14_64, Mips::D15_64,
71  Mips::D16_64, Mips::D17_64, Mips::D18_64, Mips::D19_64
72};
73
74// If I is a shifted mask, set the size (Size) and the first bit of the
75// mask (Pos), and return true.
76// For example, if I is 0x003ff800, (Pos, Size) = (11, 11).
77static bool IsShiftedMask(uint64_t I, uint64_t &Pos, uint64_t &Size) {
78  if (!isShiftedMask_64(I))
79     return false;
80
81  Size = CountPopulation_64(I);
82  Pos = CountTrailingZeros_64(I);
83  return true;
84}
85
86static SDValue GetGlobalReg(SelectionDAG &DAG, EVT Ty) {
87  MipsFunctionInfo *FI = DAG.getMachineFunction().getInfo<MipsFunctionInfo>();
88  return DAG.getRegister(FI->getGlobalBaseReg(), Ty);
89}
90
91static SDValue getTargetNode(SDValue Op, SelectionDAG &DAG, unsigned Flag) {
92  EVT Ty = Op.getValueType();
93
94  if (GlobalAddressSDNode *N = dyn_cast<GlobalAddressSDNode>(Op))
95    return DAG.getTargetGlobalAddress(N->getGlobal(), Op.getDebugLoc(), Ty, 0,
96                                      Flag);
97  if (ExternalSymbolSDNode *N = dyn_cast<ExternalSymbolSDNode>(Op))
98    return DAG.getTargetExternalSymbol(N->getSymbol(), Ty, Flag);
99  if (BlockAddressSDNode *N = dyn_cast<BlockAddressSDNode>(Op))
100    return DAG.getTargetBlockAddress(N->getBlockAddress(), Ty, 0, Flag);
101  if (JumpTableSDNode *N = dyn_cast<JumpTableSDNode>(Op))
102    return DAG.getTargetJumpTable(N->getIndex(), Ty, Flag);
103  if (ConstantPoolSDNode *N = dyn_cast<ConstantPoolSDNode>(Op))
104    return DAG.getTargetConstantPool(N->getConstVal(), Ty, N->getAlignment(),
105                                     N->getOffset(), Flag);
106
107  llvm_unreachable("Unexpected node type.");
108  return SDValue();
109}
110
111static SDValue getAddrNonPIC(SDValue Op, SelectionDAG &DAG) {
112  DebugLoc DL = Op.getDebugLoc();
113  EVT Ty = Op.getValueType();
114  SDValue Hi = getTargetNode(Op, DAG, MipsII::MO_ABS_HI);
115  SDValue Lo = getTargetNode(Op, DAG, MipsII::MO_ABS_LO);
116  return DAG.getNode(ISD::ADD, DL, Ty,
117                     DAG.getNode(MipsISD::Hi, DL, Ty, Hi),
118                     DAG.getNode(MipsISD::Lo, DL, Ty, Lo));
119}
120
121static SDValue getAddrLocal(SDValue Op, SelectionDAG &DAG, bool HasMips64) {
122  DebugLoc DL = Op.getDebugLoc();
123  EVT Ty = Op.getValueType();
124  unsigned GOTFlag = HasMips64 ? MipsII::MO_GOT_PAGE : MipsII::MO_GOT;
125  SDValue GOT = DAG.getNode(MipsISD::Wrapper, DL, Ty, GetGlobalReg(DAG, Ty),
126                            getTargetNode(Op, DAG, GOTFlag));
127  SDValue Load = DAG.getLoad(Ty, DL, DAG.getEntryNode(), GOT,
128                             MachinePointerInfo::getGOT(), false, false, false,
129                             0);
130  unsigned LoFlag = HasMips64 ? MipsII::MO_GOT_OFST : MipsII::MO_ABS_LO;
131  SDValue Lo = DAG.getNode(MipsISD::Lo, DL, Ty, getTargetNode(Op, DAG, LoFlag));
132  return DAG.getNode(ISD::ADD, DL, Ty, Load, Lo);
133}
134
135static SDValue getAddrGlobal(SDValue Op, SelectionDAG &DAG, unsigned Flag) {
136  DebugLoc DL = Op.getDebugLoc();
137  EVT Ty = Op.getValueType();
138  SDValue Tgt = DAG.getNode(MipsISD::Wrapper, DL, Ty, GetGlobalReg(DAG, Ty),
139                            getTargetNode(Op, DAG, Flag));
140  return DAG.getLoad(Ty, DL, DAG.getEntryNode(), Tgt,
141                     MachinePointerInfo::getGOT(), false, false, false, 0);
142}
143
144static SDValue getAddrGlobalLargeGOT(SDValue Op, SelectionDAG &DAG,
145                                     unsigned HiFlag, unsigned LoFlag) {
146  DebugLoc DL = Op.getDebugLoc();
147  EVT Ty = Op.getValueType();
148  SDValue Hi = DAG.getNode(MipsISD::Hi, DL, Ty, getTargetNode(Op, DAG, HiFlag));
149  Hi = DAG.getNode(ISD::ADD, DL, Ty, Hi, GetGlobalReg(DAG, Ty));
150  SDValue Wrapper = DAG.getNode(MipsISD::Wrapper, DL, Ty, Hi,
151                                getTargetNode(Op, DAG, LoFlag));
152  return DAG.getLoad(Ty, DL, DAG.getEntryNode(), Wrapper,
153                     MachinePointerInfo::getGOT(), false, false, false, 0);
154}
155
156const char *MipsTargetLowering::getTargetNodeName(unsigned Opcode) const {
157  switch (Opcode) {
158  case MipsISD::JmpLink:           return "MipsISD::JmpLink";
159  case MipsISD::TailCall:          return "MipsISD::TailCall";
160  case MipsISD::Hi:                return "MipsISD::Hi";
161  case MipsISD::Lo:                return "MipsISD::Lo";
162  case MipsISD::GPRel:             return "MipsISD::GPRel";
163  case MipsISD::ThreadPointer:     return "MipsISD::ThreadPointer";
164  case MipsISD::Ret:               return "MipsISD::Ret";
165  case MipsISD::FPBrcond:          return "MipsISD::FPBrcond";
166  case MipsISD::FPCmp:             return "MipsISD::FPCmp";
167  case MipsISD::CMovFP_T:          return "MipsISD::CMovFP_T";
168  case MipsISD::CMovFP_F:          return "MipsISD::CMovFP_F";
169  case MipsISD::FPRound:           return "MipsISD::FPRound";
170  case MipsISD::MAdd:              return "MipsISD::MAdd";
171  case MipsISD::MAddu:             return "MipsISD::MAddu";
172  case MipsISD::MSub:              return "MipsISD::MSub";
173  case MipsISD::MSubu:             return "MipsISD::MSubu";
174  case MipsISD::DivRem:            return "MipsISD::DivRem";
175  case MipsISD::DivRemU:           return "MipsISD::DivRemU";
176  case MipsISD::BuildPairF64:      return "MipsISD::BuildPairF64";
177  case MipsISD::ExtractElementF64: return "MipsISD::ExtractElementF64";
178  case MipsISD::Wrapper:           return "MipsISD::Wrapper";
179  case MipsISD::Sync:              return "MipsISD::Sync";
180  case MipsISD::Ext:               return "MipsISD::Ext";
181  case MipsISD::Ins:               return "MipsISD::Ins";
182  case MipsISD::LWL:               return "MipsISD::LWL";
183  case MipsISD::LWR:               return "MipsISD::LWR";
184  case MipsISD::SWL:               return "MipsISD::SWL";
185  case MipsISD::SWR:               return "MipsISD::SWR";
186  case MipsISD::LDL:               return "MipsISD::LDL";
187  case MipsISD::LDR:               return "MipsISD::LDR";
188  case MipsISD::SDL:               return "MipsISD::SDL";
189  case MipsISD::SDR:               return "MipsISD::SDR";
190  case MipsISD::EXTP:              return "MipsISD::EXTP";
191  case MipsISD::EXTPDP:            return "MipsISD::EXTPDP";
192  case MipsISD::EXTR_S_H:          return "MipsISD::EXTR_S_H";
193  case MipsISD::EXTR_W:            return "MipsISD::EXTR_W";
194  case MipsISD::EXTR_R_W:          return "MipsISD::EXTR_R_W";
195  case MipsISD::EXTR_RS_W:         return "MipsISD::EXTR_RS_W";
196  case MipsISD::SHILO:             return "MipsISD::SHILO";
197  case MipsISD::MTHLIP:            return "MipsISD::MTHLIP";
198  case MipsISD::MULT:              return "MipsISD::MULT";
199  case MipsISD::MULTU:             return "MipsISD::MULTU";
200  case MipsISD::MADD_DSP:          return "MipsISD::MADD_DSPDSP";
201  case MipsISD::MADDU_DSP:         return "MipsISD::MADDU_DSP";
202  case MipsISD::MSUB_DSP:          return "MipsISD::MSUB_DSP";
203  case MipsISD::MSUBU_DSP:         return "MipsISD::MSUBU_DSP";
204  default:                         return NULL;
205  }
206}
207
208void MipsTargetLowering::setMips16HardFloatLibCalls() {
209  setLibcallName(RTLIB::ADD_F32, "__mips16_addsf3");
210  setLibcallName(RTLIB::ADD_F64, "__mips16_adddf3");
211  setLibcallName(RTLIB::SUB_F32, "__mips16_subsf3");
212  setLibcallName(RTLIB::SUB_F64, "__mips16_subdf3");
213  setLibcallName(RTLIB::MUL_F32, "__mips16_mulsf3");
214  setLibcallName(RTLIB::MUL_F64, "__mips16_muldf3");
215  setLibcallName(RTLIB::DIV_F32, "__mips16_divsf3");
216  setLibcallName(RTLIB::DIV_F64, "__mips16_divdf3");
217  setLibcallName(RTLIB::FPEXT_F32_F64, "__mips16_extendsfdf2");
218  setLibcallName(RTLIB::FPROUND_F64_F32, "__mips16_truncdfsf2");
219  setLibcallName(RTLIB::FPTOSINT_F32_I32, "__mips16_fix_truncsfsi");
220  setLibcallName(RTLIB::FPTOSINT_F64_I32, "__mips16_fix_truncdfsi");
221  setLibcallName(RTLIB::SINTTOFP_I32_F32, "__mips16_floatsisf");
222  setLibcallName(RTLIB::SINTTOFP_I32_F64, "__mips16_floatsidf");
223  setLibcallName(RTLIB::UINTTOFP_I32_F32, "__mips16_floatunsisf");
224  setLibcallName(RTLIB::UINTTOFP_I32_F64, "__mips16_floatunsidf");
225  setLibcallName(RTLIB::OEQ_F32, "__mips16_eqsf2");
226  setLibcallName(RTLIB::OEQ_F64, "__mips16_eqdf2");
227  setLibcallName(RTLIB::UNE_F32, "__mips16_nesf2");
228  setLibcallName(RTLIB::UNE_F64, "__mips16_nedf2");
229  setLibcallName(RTLIB::OGE_F32, "__mips16_gesf2");
230  setLibcallName(RTLIB::OGE_F64, "__mips16_gedf2");
231  setLibcallName(RTLIB::OLT_F32, "__mips16_ltsf2");
232  setLibcallName(RTLIB::OLT_F64, "__mips16_ltdf2");
233  setLibcallName(RTLIB::OLE_F32, "__mips16_lesf2");
234  setLibcallName(RTLIB::OLE_F64, "__mips16_ledf2");
235  setLibcallName(RTLIB::OGT_F32, "__mips16_gtsf2");
236  setLibcallName(RTLIB::OGT_F64, "__mips16_gtdf2");
237  setLibcallName(RTLIB::UO_F32, "__mips16_unordsf2");
238  setLibcallName(RTLIB::UO_F64, "__mips16_unorddf2");
239  setLibcallName(RTLIB::O_F32, "__mips16_unordsf2");
240  setLibcallName(RTLIB::O_F64, "__mips16_unorddf2");
241}
242
243MipsTargetLowering::
244MipsTargetLowering(MipsTargetMachine &TM)
245  : TargetLowering(TM, new MipsTargetObjectFile()),
246    Subtarget(&TM.getSubtarget<MipsSubtarget>()),
247    HasMips64(Subtarget->hasMips64()), IsN64(Subtarget->isABI_N64()),
248    IsO32(Subtarget->isABI_O32()) {
249
250  // Mips does not have i1 type, so use i32 for
251  // setcc operations results (slt, sgt, ...).
252  setBooleanContents(ZeroOrOneBooleanContent);
253  setBooleanVectorContents(ZeroOrOneBooleanContent); // FIXME: Is this correct?
254
255  // Set up the register classes
256  addRegisterClass(MVT::i32, &Mips::CPURegsRegClass);
257
258  if (HasMips64)
259    addRegisterClass(MVT::i64, &Mips::CPU64RegsRegClass);
260
261  if (Subtarget->inMips16Mode()) {
262    addRegisterClass(MVT::i32, &Mips::CPU16RegsRegClass);
263    if (Mips16HardFloat)
264      setMips16HardFloatLibCalls();
265  }
266
267  if (Subtarget->hasDSP()) {
268    MVT::SimpleValueType VecTys[2] = {MVT::v2i16, MVT::v4i8};
269
270    for (unsigned i = 0; i < array_lengthof(VecTys); ++i) {
271      addRegisterClass(VecTys[i], &Mips::DSPRegsRegClass);
272
273      // Expand all builtin opcodes.
274      for (unsigned Opc = 0; Opc < ISD::BUILTIN_OP_END; ++Opc)
275        setOperationAction(Opc, VecTys[i], Expand);
276
277      setOperationAction(ISD::LOAD, VecTys[i], Legal);
278      setOperationAction(ISD::STORE, VecTys[i], Legal);
279      setOperationAction(ISD::BITCAST, VecTys[i], Legal);
280    }
281  }
282
283  if (!TM.Options.UseSoftFloat) {
284    addRegisterClass(MVT::f32, &Mips::FGR32RegClass);
285
286    // When dealing with single precision only, use libcalls
287    if (!Subtarget->isSingleFloat()) {
288      if (HasMips64)
289        addRegisterClass(MVT::f64, &Mips::FGR64RegClass);
290      else
291        addRegisterClass(MVT::f64, &Mips::AFGR64RegClass);
292    }
293  }
294
295  // Load extented operations for i1 types must be promoted
296  setLoadExtAction(ISD::EXTLOAD,  MVT::i1,  Promote);
297  setLoadExtAction(ISD::ZEXTLOAD, MVT::i1,  Promote);
298  setLoadExtAction(ISD::SEXTLOAD, MVT::i1,  Promote);
299
300  // MIPS doesn't have extending float->double load/store
301  setLoadExtAction(ISD::EXTLOAD, MVT::f32, Expand);
302  setTruncStoreAction(MVT::f64, MVT::f32, Expand);
303
304  // Used by legalize types to correctly generate the setcc result.
305  // Without this, every float setcc comes with a AND/OR with the result,
306  // we don't want this, since the fpcmp result goes to a flag register,
307  // which is used implicitly by brcond and select operations.
308  AddPromotedToType(ISD::SETCC, MVT::i1, MVT::i32);
309
310  // Mips Custom Operations
311  setOperationAction(ISD::GlobalAddress,      MVT::i32,   Custom);
312  setOperationAction(ISD::BlockAddress,       MVT::i32,   Custom);
313  setOperationAction(ISD::GlobalTLSAddress,   MVT::i32,   Custom);
314  setOperationAction(ISD::JumpTable,          MVT::i32,   Custom);
315  setOperationAction(ISD::ConstantPool,       MVT::i32,   Custom);
316  setOperationAction(ISD::SELECT,             MVT::f32,   Custom);
317  setOperationAction(ISD::SELECT,             MVT::f64,   Custom);
318  setOperationAction(ISD::SELECT,             MVT::i32,   Custom);
319  setOperationAction(ISD::SELECT_CC,          MVT::f32,   Custom);
320  setOperationAction(ISD::SELECT_CC,          MVT::f64,   Custom);
321  setOperationAction(ISD::SETCC,              MVT::f32,   Custom);
322  setOperationAction(ISD::SETCC,              MVT::f64,   Custom);
323  setOperationAction(ISD::BRCOND,             MVT::Other, Custom);
324  setOperationAction(ISD::VASTART,            MVT::Other, Custom);
325  setOperationAction(ISD::FCOPYSIGN,          MVT::f32,   Custom);
326  setOperationAction(ISD::FCOPYSIGN,          MVT::f64,   Custom);
327  if (Subtarget->inMips16Mode()) {
328    setOperationAction(ISD::MEMBARRIER,         MVT::Other, Expand);
329    setOperationAction(ISD::ATOMIC_FENCE,       MVT::Other, Expand);
330  }
331  else {
332    setOperationAction(ISD::MEMBARRIER,         MVT::Other, Custom);
333    setOperationAction(ISD::ATOMIC_FENCE,       MVT::Other, Custom);
334  }
335  if (!Subtarget->inMips16Mode()) {
336    setOperationAction(ISD::LOAD,               MVT::i32, Custom);
337    setOperationAction(ISD::STORE,              MVT::i32, Custom);
338  }
339
340  if (!TM.Options.NoNaNsFPMath) {
341    setOperationAction(ISD::FABS,             MVT::f32,   Custom);
342    setOperationAction(ISD::FABS,             MVT::f64,   Custom);
343  }
344
345  if (HasMips64) {
346    setOperationAction(ISD::GlobalAddress,      MVT::i64,   Custom);
347    setOperationAction(ISD::BlockAddress,       MVT::i64,   Custom);
348    setOperationAction(ISD::GlobalTLSAddress,   MVT::i64,   Custom);
349    setOperationAction(ISD::JumpTable,          MVT::i64,   Custom);
350    setOperationAction(ISD::ConstantPool,       MVT::i64,   Custom);
351    setOperationAction(ISD::SELECT,             MVT::i64,   Custom);
352    setOperationAction(ISD::LOAD,               MVT::i64,   Custom);
353    setOperationAction(ISD::STORE,              MVT::i64,   Custom);
354  }
355
356  if (!HasMips64) {
357    setOperationAction(ISD::SHL_PARTS,          MVT::i32,   Custom);
358    setOperationAction(ISD::SRA_PARTS,          MVT::i32,   Custom);
359    setOperationAction(ISD::SRL_PARTS,          MVT::i32,   Custom);
360  }
361
362  setOperationAction(ISD::ADD,                MVT::i32,   Custom);
363  if (HasMips64)
364    setOperationAction(ISD::ADD,                MVT::i64,   Custom);
365
366  setOperationAction(ISD::SDIV, MVT::i32, Expand);
367  setOperationAction(ISD::SREM, MVT::i32, Expand);
368  setOperationAction(ISD::UDIV, MVT::i32, Expand);
369  setOperationAction(ISD::UREM, MVT::i32, Expand);
370  setOperationAction(ISD::SDIV, MVT::i64, Expand);
371  setOperationAction(ISD::SREM, MVT::i64, Expand);
372  setOperationAction(ISD::UDIV, MVT::i64, Expand);
373  setOperationAction(ISD::UREM, MVT::i64, Expand);
374
375  // Operations not directly supported by Mips.
376  setOperationAction(ISD::BR_JT,             MVT::Other, Expand);
377  setOperationAction(ISD::BR_CC,             MVT::Other, Expand);
378  setOperationAction(ISD::SELECT_CC,         MVT::Other, Expand);
379  setOperationAction(ISD::UINT_TO_FP,        MVT::i32,   Expand);
380  setOperationAction(ISD::UINT_TO_FP,        MVT::i64,   Expand);
381  setOperationAction(ISD::FP_TO_UINT,        MVT::i32,   Expand);
382  setOperationAction(ISD::FP_TO_UINT,        MVT::i64,   Expand);
383  setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i1,    Expand);
384  setOperationAction(ISD::CTPOP,             MVT::i32,   Expand);
385  setOperationAction(ISD::CTPOP,             MVT::i64,   Expand);
386  setOperationAction(ISD::CTTZ,              MVT::i32,   Expand);
387  setOperationAction(ISD::CTTZ,              MVT::i64,   Expand);
388  setOperationAction(ISD::CTTZ_ZERO_UNDEF,   MVT::i32,   Expand);
389  setOperationAction(ISD::CTTZ_ZERO_UNDEF,   MVT::i64,   Expand);
390  setOperationAction(ISD::CTLZ_ZERO_UNDEF,   MVT::i32,   Expand);
391  setOperationAction(ISD::CTLZ_ZERO_UNDEF,   MVT::i64,   Expand);
392  setOperationAction(ISD::ROTL,              MVT::i32,   Expand);
393  setOperationAction(ISD::ROTL,              MVT::i64,   Expand);
394  setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32,  Expand);
395  setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i64,  Expand);
396
397  if (!Subtarget->hasMips32r2())
398    setOperationAction(ISD::ROTR, MVT::i32,   Expand);
399
400  if (!Subtarget->hasMips64r2())
401    setOperationAction(ISD::ROTR, MVT::i64,   Expand);
402
403  setOperationAction(ISD::FSIN,              MVT::f32,   Expand);
404  setOperationAction(ISD::FSIN,              MVT::f64,   Expand);
405  setOperationAction(ISD::FCOS,              MVT::f32,   Expand);
406  setOperationAction(ISD::FCOS,              MVT::f64,   Expand);
407  setOperationAction(ISD::FPOWI,             MVT::f32,   Expand);
408  setOperationAction(ISD::FPOW,              MVT::f32,   Expand);
409  setOperationAction(ISD::FPOW,              MVT::f64,   Expand);
410  setOperationAction(ISD::FLOG,              MVT::f32,   Expand);
411  setOperationAction(ISD::FLOG2,             MVT::f32,   Expand);
412  setOperationAction(ISD::FLOG10,            MVT::f32,   Expand);
413  setOperationAction(ISD::FEXP,              MVT::f32,   Expand);
414  setOperationAction(ISD::FMA,               MVT::f32,   Expand);
415  setOperationAction(ISD::FMA,               MVT::f64,   Expand);
416  setOperationAction(ISD::FREM,              MVT::f32,   Expand);
417  setOperationAction(ISD::FREM,              MVT::f64,   Expand);
418
419  if (!TM.Options.NoNaNsFPMath) {
420    setOperationAction(ISD::FNEG,             MVT::f32,   Expand);
421    setOperationAction(ISD::FNEG,             MVT::f64,   Expand);
422  }
423
424  setOperationAction(ISD::EXCEPTIONADDR,     MVT::i32, Expand);
425  setOperationAction(ISD::EXCEPTIONADDR,     MVT::i64, Expand);
426  setOperationAction(ISD::EHSELECTION,       MVT::i32, Expand);
427  setOperationAction(ISD::EHSELECTION,       MVT::i64, Expand);
428
429  setOperationAction(ISD::VAARG,             MVT::Other, Expand);
430  setOperationAction(ISD::VACOPY,            MVT::Other, Expand);
431  setOperationAction(ISD::VAEND,             MVT::Other, Expand);
432
433  setOperationAction(ISD::INTRINSIC_WO_CHAIN, MVT::i64, Custom);
434  setOperationAction(ISD::INTRINSIC_W_CHAIN, MVT::i64, Custom);
435
436  // Use the default for now
437  setOperationAction(ISD::STACKSAVE,         MVT::Other, Expand);
438  setOperationAction(ISD::STACKRESTORE,      MVT::Other, Expand);
439
440  setOperationAction(ISD::ATOMIC_LOAD,       MVT::i32,    Expand);
441  setOperationAction(ISD::ATOMIC_LOAD,       MVT::i64,    Expand);
442  setOperationAction(ISD::ATOMIC_STORE,      MVT::i32,    Expand);
443  setOperationAction(ISD::ATOMIC_STORE,      MVT::i64,    Expand);
444
445  if (Subtarget->inMips16Mode()) {
446    setOperationAction(ISD::ATOMIC_CMP_SWAP,       MVT::i32,    Expand);
447    setOperationAction(ISD::ATOMIC_SWAP,           MVT::i32,    Expand);
448    setOperationAction(ISD::ATOMIC_LOAD_ADD,       MVT::i32,    Expand);
449    setOperationAction(ISD::ATOMIC_LOAD_SUB,       MVT::i32,    Expand);
450    setOperationAction(ISD::ATOMIC_LOAD_AND,       MVT::i32,    Expand);
451    setOperationAction(ISD::ATOMIC_LOAD_OR,        MVT::i32,    Expand);
452    setOperationAction(ISD::ATOMIC_LOAD_XOR,       MVT::i32,    Expand);
453    setOperationAction(ISD::ATOMIC_LOAD_NAND,      MVT::i32,    Expand);
454    setOperationAction(ISD::ATOMIC_LOAD_MIN,       MVT::i32,    Expand);
455    setOperationAction(ISD::ATOMIC_LOAD_MAX,       MVT::i32,    Expand);
456    setOperationAction(ISD::ATOMIC_LOAD_UMIN,      MVT::i32,    Expand);
457    setOperationAction(ISD::ATOMIC_LOAD_UMAX,      MVT::i32,    Expand);
458  }
459
460  setInsertFencesForAtomic(true);
461
462  if (!Subtarget->hasSEInReg()) {
463    setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i8,  Expand);
464    setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i16, Expand);
465  }
466
467  if (!Subtarget->hasBitCount()) {
468    setOperationAction(ISD::CTLZ, MVT::i32, Expand);
469    setOperationAction(ISD::CTLZ, MVT::i64, Expand);
470  }
471
472  if (!Subtarget->hasSwap()) {
473    setOperationAction(ISD::BSWAP, MVT::i32, Expand);
474    setOperationAction(ISD::BSWAP, MVT::i64, Expand);
475  }
476
477  if (HasMips64) {
478    setLoadExtAction(ISD::SEXTLOAD, MVT::i32, Custom);
479    setLoadExtAction(ISD::ZEXTLOAD, MVT::i32, Custom);
480    setLoadExtAction(ISD::EXTLOAD, MVT::i32, Custom);
481    setTruncStoreAction(MVT::i64, MVT::i32, Custom);
482  }
483
484  setTargetDAGCombine(ISD::ADDE);
485  setTargetDAGCombine(ISD::SUBE);
486  setTargetDAGCombine(ISD::SDIVREM);
487  setTargetDAGCombine(ISD::UDIVREM);
488  setTargetDAGCombine(ISD::SELECT);
489  setTargetDAGCombine(ISD::AND);
490  setTargetDAGCombine(ISD::OR);
491  setTargetDAGCombine(ISD::ADD);
492
493  setMinFunctionAlignment(HasMips64 ? 3 : 2);
494
495  setStackPointerRegisterToSaveRestore(IsN64 ? Mips::SP_64 : Mips::SP);
496  computeRegisterProperties();
497
498  setExceptionPointerRegister(IsN64 ? Mips::A0_64 : Mips::A0);
499  setExceptionSelectorRegister(IsN64 ? Mips::A1_64 : Mips::A1);
500
501  maxStoresPerMemcpy = 16;
502}
503
504bool
505MipsTargetLowering::allowsUnalignedMemoryAccesses(EVT VT, bool *Fast) const {
506  MVT::SimpleValueType SVT = VT.getSimpleVT().SimpleTy;
507
508  if (Subtarget->inMips16Mode())
509    return false;
510
511  switch (SVT) {
512  case MVT::i64:
513  case MVT::i32:
514    if (Fast)
515      *Fast = true;
516    return true;
517  default:
518    return false;
519  }
520}
521
522EVT MipsTargetLowering::getSetCCResultType(EVT VT) const {
523  return MVT::i32;
524}
525
526// SelectMadd -
527// Transforms a subgraph in CurDAG if the following pattern is found:
528//  (addc multLo, Lo0), (adde multHi, Hi0),
529// where,
530//  multHi/Lo: product of multiplication
531//  Lo0: initial value of Lo register
532//  Hi0: initial value of Hi register
533// Return true if pattern matching was successful.
534static bool SelectMadd(SDNode *ADDENode, SelectionDAG *CurDAG) {
535  // ADDENode's second operand must be a flag output of an ADDC node in order
536  // for the matching to be successful.
537  SDNode *ADDCNode = ADDENode->getOperand(2).getNode();
538
539  if (ADDCNode->getOpcode() != ISD::ADDC)
540    return false;
541
542  SDValue MultHi = ADDENode->getOperand(0);
543  SDValue MultLo = ADDCNode->getOperand(0);
544  SDNode *MultNode = MultHi.getNode();
545  unsigned MultOpc = MultHi.getOpcode();
546
547  // MultHi and MultLo must be generated by the same node,
548  if (MultLo.getNode() != MultNode)
549    return false;
550
551  // and it must be a multiplication.
552  if (MultOpc != ISD::SMUL_LOHI && MultOpc != ISD::UMUL_LOHI)
553    return false;
554
555  // MultLo amd MultHi must be the first and second output of MultNode
556  // respectively.
557  if (MultHi.getResNo() != 1 || MultLo.getResNo() != 0)
558    return false;
559
560  // Transform this to a MADD only if ADDENode and ADDCNode are the only users
561  // of the values of MultNode, in which case MultNode will be removed in later
562  // phases.
563  // If there exist users other than ADDENode or ADDCNode, this function returns
564  // here, which will result in MultNode being mapped to a single MULT
565  // instruction node rather than a pair of MULT and MADD instructions being
566  // produced.
567  if (!MultHi.hasOneUse() || !MultLo.hasOneUse())
568    return false;
569
570  SDValue Chain = CurDAG->getEntryNode();
571  DebugLoc dl = ADDENode->getDebugLoc();
572
573  // create MipsMAdd(u) node
574  MultOpc = MultOpc == ISD::UMUL_LOHI ? MipsISD::MAddu : MipsISD::MAdd;
575
576  SDValue MAdd = CurDAG->getNode(MultOpc, dl, MVT::Glue,
577                                 MultNode->getOperand(0),// Factor 0
578                                 MultNode->getOperand(1),// Factor 1
579                                 ADDCNode->getOperand(1),// Lo0
580                                 ADDENode->getOperand(1));// Hi0
581
582  // create CopyFromReg nodes
583  SDValue CopyFromLo = CurDAG->getCopyFromReg(Chain, dl, Mips::LO, MVT::i32,
584                                              MAdd);
585  SDValue CopyFromHi = CurDAG->getCopyFromReg(CopyFromLo.getValue(1), dl,
586                                              Mips::HI, MVT::i32,
587                                              CopyFromLo.getValue(2));
588
589  // replace uses of adde and addc here
590  if (!SDValue(ADDCNode, 0).use_empty())
591    CurDAG->ReplaceAllUsesOfValueWith(SDValue(ADDCNode, 0), CopyFromLo);
592
593  if (!SDValue(ADDENode, 0).use_empty())
594    CurDAG->ReplaceAllUsesOfValueWith(SDValue(ADDENode, 0), CopyFromHi);
595
596  return true;
597}
598
599// SelectMsub -
600// Transforms a subgraph in CurDAG if the following pattern is found:
601//  (addc Lo0, multLo), (sube Hi0, multHi),
602// where,
603//  multHi/Lo: product of multiplication
604//  Lo0: initial value of Lo register
605//  Hi0: initial value of Hi register
606// Return true if pattern matching was successful.
607static bool SelectMsub(SDNode *SUBENode, SelectionDAG *CurDAG) {
608  // SUBENode's second operand must be a flag output of an SUBC node in order
609  // for the matching to be successful.
610  SDNode *SUBCNode = SUBENode->getOperand(2).getNode();
611
612  if (SUBCNode->getOpcode() != ISD::SUBC)
613    return false;
614
615  SDValue MultHi = SUBENode->getOperand(1);
616  SDValue MultLo = SUBCNode->getOperand(1);
617  SDNode *MultNode = MultHi.getNode();
618  unsigned MultOpc = MultHi.getOpcode();
619
620  // MultHi and MultLo must be generated by the same node,
621  if (MultLo.getNode() != MultNode)
622    return false;
623
624  // and it must be a multiplication.
625  if (MultOpc != ISD::SMUL_LOHI && MultOpc != ISD::UMUL_LOHI)
626    return false;
627
628  // MultLo amd MultHi must be the first and second output of MultNode
629  // respectively.
630  if (MultHi.getResNo() != 1 || MultLo.getResNo() != 0)
631    return false;
632
633  // Transform this to a MSUB only if SUBENode and SUBCNode are the only users
634  // of the values of MultNode, in which case MultNode will be removed in later
635  // phases.
636  // If there exist users other than SUBENode or SUBCNode, this function returns
637  // here, which will result in MultNode being mapped to a single MULT
638  // instruction node rather than a pair of MULT and MSUB instructions being
639  // produced.
640  if (!MultHi.hasOneUse() || !MultLo.hasOneUse())
641    return false;
642
643  SDValue Chain = CurDAG->getEntryNode();
644  DebugLoc dl = SUBENode->getDebugLoc();
645
646  // create MipsSub(u) node
647  MultOpc = MultOpc == ISD::UMUL_LOHI ? MipsISD::MSubu : MipsISD::MSub;
648
649  SDValue MSub = CurDAG->getNode(MultOpc, dl, MVT::Glue,
650                                 MultNode->getOperand(0),// Factor 0
651                                 MultNode->getOperand(1),// Factor 1
652                                 SUBCNode->getOperand(0),// Lo0
653                                 SUBENode->getOperand(0));// Hi0
654
655  // create CopyFromReg nodes
656  SDValue CopyFromLo = CurDAG->getCopyFromReg(Chain, dl, Mips::LO, MVT::i32,
657                                              MSub);
658  SDValue CopyFromHi = CurDAG->getCopyFromReg(CopyFromLo.getValue(1), dl,
659                                              Mips::HI, MVT::i32,
660                                              CopyFromLo.getValue(2));
661
662  // replace uses of sube and subc here
663  if (!SDValue(SUBCNode, 0).use_empty())
664    CurDAG->ReplaceAllUsesOfValueWith(SDValue(SUBCNode, 0), CopyFromLo);
665
666  if (!SDValue(SUBENode, 0).use_empty())
667    CurDAG->ReplaceAllUsesOfValueWith(SDValue(SUBENode, 0), CopyFromHi);
668
669  return true;
670}
671
672static SDValue PerformADDECombine(SDNode *N, SelectionDAG &DAG,
673                                  TargetLowering::DAGCombinerInfo &DCI,
674                                  const MipsSubtarget *Subtarget) {
675  if (DCI.isBeforeLegalize())
676    return SDValue();
677
678  if (Subtarget->hasMips32() && N->getValueType(0) == MVT::i32 &&
679      SelectMadd(N, &DAG))
680    return SDValue(N, 0);
681
682  return SDValue();
683}
684
685static SDValue PerformSUBECombine(SDNode *N, SelectionDAG &DAG,
686                                  TargetLowering::DAGCombinerInfo &DCI,
687                                  const MipsSubtarget *Subtarget) {
688  if (DCI.isBeforeLegalize())
689    return SDValue();
690
691  if (Subtarget->hasMips32() && N->getValueType(0) == MVT::i32 &&
692      SelectMsub(N, &DAG))
693    return SDValue(N, 0);
694
695  return SDValue();
696}
697
698static SDValue PerformDivRemCombine(SDNode *N, SelectionDAG &DAG,
699                                    TargetLowering::DAGCombinerInfo &DCI,
700                                    const MipsSubtarget *Subtarget) {
701  if (DCI.isBeforeLegalizeOps())
702    return SDValue();
703
704  EVT Ty = N->getValueType(0);
705  unsigned LO = (Ty == MVT::i32) ? Mips::LO : Mips::LO64;
706  unsigned HI = (Ty == MVT::i32) ? Mips::HI : Mips::HI64;
707  unsigned opc = N->getOpcode() == ISD::SDIVREM ? MipsISD::DivRem :
708                                                  MipsISD::DivRemU;
709  DebugLoc dl = N->getDebugLoc();
710
711  SDValue DivRem = DAG.getNode(opc, dl, MVT::Glue,
712                               N->getOperand(0), N->getOperand(1));
713  SDValue InChain = DAG.getEntryNode();
714  SDValue InGlue = DivRem;
715
716  // insert MFLO
717  if (N->hasAnyUseOfValue(0)) {
718    SDValue CopyFromLo = DAG.getCopyFromReg(InChain, dl, LO, Ty,
719                                            InGlue);
720    DAG.ReplaceAllUsesOfValueWith(SDValue(N, 0), CopyFromLo);
721    InChain = CopyFromLo.getValue(1);
722    InGlue = CopyFromLo.getValue(2);
723  }
724
725  // insert MFHI
726  if (N->hasAnyUseOfValue(1)) {
727    SDValue CopyFromHi = DAG.getCopyFromReg(InChain, dl,
728                                            HI, Ty, InGlue);
729    DAG.ReplaceAllUsesOfValueWith(SDValue(N, 1), CopyFromHi);
730  }
731
732  return SDValue();
733}
734
735static Mips::CondCode FPCondCCodeToFCC(ISD::CondCode CC) {
736  switch (CC) {
737  default: llvm_unreachable("Unknown fp condition code!");
738  case ISD::SETEQ:
739  case ISD::SETOEQ: return Mips::FCOND_OEQ;
740  case ISD::SETUNE: return Mips::FCOND_UNE;
741  case ISD::SETLT:
742  case ISD::SETOLT: return Mips::FCOND_OLT;
743  case ISD::SETGT:
744  case ISD::SETOGT: return Mips::FCOND_OGT;
745  case ISD::SETLE:
746  case ISD::SETOLE: return Mips::FCOND_OLE;
747  case ISD::SETGE:
748  case ISD::SETOGE: return Mips::FCOND_OGE;
749  case ISD::SETULT: return Mips::FCOND_ULT;
750  case ISD::SETULE: return Mips::FCOND_ULE;
751  case ISD::SETUGT: return Mips::FCOND_UGT;
752  case ISD::SETUGE: return Mips::FCOND_UGE;
753  case ISD::SETUO:  return Mips::FCOND_UN;
754  case ISD::SETO:   return Mips::FCOND_OR;
755  case ISD::SETNE:
756  case ISD::SETONE: return Mips::FCOND_ONE;
757  case ISD::SETUEQ: return Mips::FCOND_UEQ;
758  }
759}
760
761
762// Returns true if condition code has to be inverted.
763static bool InvertFPCondCode(Mips::CondCode CC) {
764  if (CC >= Mips::FCOND_F && CC <= Mips::FCOND_NGT)
765    return false;
766
767  assert((CC >= Mips::FCOND_T && CC <= Mips::FCOND_GT) &&
768         "Illegal Condition Code");
769
770  return true;
771}
772
773// Creates and returns an FPCmp node from a setcc node.
774// Returns Op if setcc is not a floating point comparison.
775static SDValue CreateFPCmp(SelectionDAG &DAG, const SDValue &Op) {
776  // must be a SETCC node
777  if (Op.getOpcode() != ISD::SETCC)
778    return Op;
779
780  SDValue LHS = Op.getOperand(0);
781
782  if (!LHS.getValueType().isFloatingPoint())
783    return Op;
784
785  SDValue RHS = Op.getOperand(1);
786  DebugLoc dl = Op.getDebugLoc();
787
788  // Assume the 3rd operand is a CondCodeSDNode. Add code to check the type of
789  // node if necessary.
790  ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(2))->get();
791
792  return DAG.getNode(MipsISD::FPCmp, dl, MVT::Glue, LHS, RHS,
793                     DAG.getConstant(FPCondCCodeToFCC(CC), MVT::i32));
794}
795
796// Creates and returns a CMovFPT/F node.
797static SDValue CreateCMovFP(SelectionDAG &DAG, SDValue Cond, SDValue True,
798                            SDValue False, DebugLoc DL) {
799  bool invert = InvertFPCondCode((Mips::CondCode)
800                                 cast<ConstantSDNode>(Cond.getOperand(2))
801                                 ->getSExtValue());
802
803  return DAG.getNode((invert ? MipsISD::CMovFP_F : MipsISD::CMovFP_T), DL,
804                     True.getValueType(), True, False, Cond);
805}
806
807static SDValue PerformSELECTCombine(SDNode *N, SelectionDAG &DAG,
808                                    TargetLowering::DAGCombinerInfo &DCI,
809                                    const MipsSubtarget *Subtarget) {
810  if (DCI.isBeforeLegalizeOps())
811    return SDValue();
812
813  SDValue SetCC = N->getOperand(0);
814
815  if ((SetCC.getOpcode() != ISD::SETCC) ||
816      !SetCC.getOperand(0).getValueType().isInteger())
817    return SDValue();
818
819  SDValue False = N->getOperand(2);
820  EVT FalseTy = False.getValueType();
821
822  if (!FalseTy.isInteger())
823    return SDValue();
824
825  ConstantSDNode *CN = dyn_cast<ConstantSDNode>(False);
826
827  if (!CN || CN->getZExtValue())
828    return SDValue();
829
830  const DebugLoc DL = N->getDebugLoc();
831  ISD::CondCode CC = cast<CondCodeSDNode>(SetCC.getOperand(2))->get();
832  SDValue True = N->getOperand(1);
833
834  SetCC = DAG.getSetCC(DL, SetCC.getValueType(), SetCC.getOperand(0),
835                       SetCC.getOperand(1), ISD::getSetCCInverse(CC, true));
836
837  return DAG.getNode(ISD::SELECT, DL, FalseTy, SetCC, False, True);
838}
839
840static SDValue PerformANDCombine(SDNode *N, SelectionDAG &DAG,
841                                 TargetLowering::DAGCombinerInfo &DCI,
842                                 const MipsSubtarget *Subtarget) {
843  // Pattern match EXT.
844  //  $dst = and ((sra or srl) $src , pos), (2**size - 1)
845  //  => ext $dst, $src, size, pos
846  if (DCI.isBeforeLegalizeOps() || !Subtarget->hasMips32r2())
847    return SDValue();
848
849  SDValue ShiftRight = N->getOperand(0), Mask = N->getOperand(1);
850  unsigned ShiftRightOpc = ShiftRight.getOpcode();
851
852  // Op's first operand must be a shift right.
853  if (ShiftRightOpc != ISD::SRA && ShiftRightOpc != ISD::SRL)
854    return SDValue();
855
856  // The second operand of the shift must be an immediate.
857  ConstantSDNode *CN;
858  if (!(CN = dyn_cast<ConstantSDNode>(ShiftRight.getOperand(1))))
859    return SDValue();
860
861  uint64_t Pos = CN->getZExtValue();
862  uint64_t SMPos, SMSize;
863
864  // Op's second operand must be a shifted mask.
865  if (!(CN = dyn_cast<ConstantSDNode>(Mask)) ||
866      !IsShiftedMask(CN->getZExtValue(), SMPos, SMSize))
867    return SDValue();
868
869  // Return if the shifted mask does not start at bit 0 or the sum of its size
870  // and Pos exceeds the word's size.
871  EVT ValTy = N->getValueType(0);
872  if (SMPos != 0 || Pos + SMSize > ValTy.getSizeInBits())
873    return SDValue();
874
875  return DAG.getNode(MipsISD::Ext, N->getDebugLoc(), ValTy,
876                     ShiftRight.getOperand(0), DAG.getConstant(Pos, MVT::i32),
877                     DAG.getConstant(SMSize, MVT::i32));
878}
879
880static SDValue PerformORCombine(SDNode *N, SelectionDAG &DAG,
881                                TargetLowering::DAGCombinerInfo &DCI,
882                                const MipsSubtarget *Subtarget) {
883  // Pattern match INS.
884  //  $dst = or (and $src1 , mask0), (and (shl $src, pos), mask1),
885  //  where mask1 = (2**size - 1) << pos, mask0 = ~mask1
886  //  => ins $dst, $src, size, pos, $src1
887  if (DCI.isBeforeLegalizeOps() || !Subtarget->hasMips32r2())
888    return SDValue();
889
890  SDValue And0 = N->getOperand(0), And1 = N->getOperand(1);
891  uint64_t SMPos0, SMSize0, SMPos1, SMSize1;
892  ConstantSDNode *CN;
893
894  // See if Op's first operand matches (and $src1 , mask0).
895  if (And0.getOpcode() != ISD::AND)
896    return SDValue();
897
898  if (!(CN = dyn_cast<ConstantSDNode>(And0.getOperand(1))) ||
899      !IsShiftedMask(~CN->getSExtValue(), SMPos0, SMSize0))
900    return SDValue();
901
902  // See if Op's second operand matches (and (shl $src, pos), mask1).
903  if (And1.getOpcode() != ISD::AND)
904    return SDValue();
905
906  if (!(CN = dyn_cast<ConstantSDNode>(And1.getOperand(1))) ||
907      !IsShiftedMask(CN->getZExtValue(), SMPos1, SMSize1))
908    return SDValue();
909
910  // The shift masks must have the same position and size.
911  if (SMPos0 != SMPos1 || SMSize0 != SMSize1)
912    return SDValue();
913
914  SDValue Shl = And1.getOperand(0);
915  if (Shl.getOpcode() != ISD::SHL)
916    return SDValue();
917
918  if (!(CN = dyn_cast<ConstantSDNode>(Shl.getOperand(1))))
919    return SDValue();
920
921  unsigned Shamt = CN->getZExtValue();
922
923  // Return if the shift amount and the first bit position of mask are not the
924  // same.
925  EVT ValTy = N->getValueType(0);
926  if ((Shamt != SMPos0) || (SMPos0 + SMSize0 > ValTy.getSizeInBits()))
927    return SDValue();
928
929  return DAG.getNode(MipsISD::Ins, N->getDebugLoc(), ValTy, Shl.getOperand(0),
930                     DAG.getConstant(SMPos0, MVT::i32),
931                     DAG.getConstant(SMSize0, MVT::i32), And0.getOperand(0));
932}
933
934static SDValue PerformADDCombine(SDNode *N, SelectionDAG &DAG,
935                                 TargetLowering::DAGCombinerInfo &DCI,
936                                 const MipsSubtarget *Subtarget) {
937  // (add v0, (add v1, abs_lo(tjt))) => (add (add v0, v1), abs_lo(tjt))
938
939  if (DCI.isBeforeLegalizeOps())
940    return SDValue();
941
942  SDValue Add = N->getOperand(1);
943
944  if (Add.getOpcode() != ISD::ADD)
945    return SDValue();
946
947  SDValue Lo = Add.getOperand(1);
948
949  if ((Lo.getOpcode() != MipsISD::Lo) ||
950      (Lo.getOperand(0).getOpcode() != ISD::TargetJumpTable))
951    return SDValue();
952
953  EVT ValTy = N->getValueType(0);
954  DebugLoc DL = N->getDebugLoc();
955
956  SDValue Add1 = DAG.getNode(ISD::ADD, DL, ValTy, N->getOperand(0),
957                             Add.getOperand(0));
958  return DAG.getNode(ISD::ADD, DL, ValTy, Add1, Lo);
959}
960
961SDValue  MipsTargetLowering::PerformDAGCombine(SDNode *N, DAGCombinerInfo &DCI)
962  const {
963  SelectionDAG &DAG = DCI.DAG;
964  unsigned opc = N->getOpcode();
965
966  switch (opc) {
967  default: break;
968  case ISD::ADDE:
969    return PerformADDECombine(N, DAG, DCI, Subtarget);
970  case ISD::SUBE:
971    return PerformSUBECombine(N, DAG, DCI, Subtarget);
972  case ISD::SDIVREM:
973  case ISD::UDIVREM:
974    return PerformDivRemCombine(N, DAG, DCI, Subtarget);
975  case ISD::SELECT:
976    return PerformSELECTCombine(N, DAG, DCI, Subtarget);
977  case ISD::AND:
978    return PerformANDCombine(N, DAG, DCI, Subtarget);
979  case ISD::OR:
980    return PerformORCombine(N, DAG, DCI, Subtarget);
981  case ISD::ADD:
982    return PerformADDCombine(N, DAG, DCI, Subtarget);
983  }
984
985  return SDValue();
986}
987
988void
989MipsTargetLowering::LowerOperationWrapper(SDNode *N,
990                                          SmallVectorImpl<SDValue> &Results,
991                                          SelectionDAG &DAG) const {
992  SDValue Res = LowerOperation(SDValue(N, 0), DAG);
993
994  for (unsigned I = 0, E = Res->getNumValues(); I != E; ++I)
995    Results.push_back(Res.getValue(I));
996}
997
998void
999MipsTargetLowering::ReplaceNodeResults(SDNode *N,
1000                                       SmallVectorImpl<SDValue> &Results,
1001                                       SelectionDAG &DAG) const {
1002  SDValue Res = LowerOperation(SDValue(N, 0), DAG);
1003
1004  for (unsigned I = 0, E = Res->getNumValues(); I != E; ++I)
1005    Results.push_back(Res.getValue(I));
1006}
1007
1008SDValue MipsTargetLowering::
1009LowerOperation(SDValue Op, SelectionDAG &DAG) const
1010{
1011  switch (Op.getOpcode())
1012  {
1013    case ISD::BRCOND:             return LowerBRCOND(Op, DAG);
1014    case ISD::ConstantPool:       return LowerConstantPool(Op, DAG);
1015    case ISD::GlobalAddress:      return LowerGlobalAddress(Op, DAG);
1016    case ISD::BlockAddress:       return LowerBlockAddress(Op, DAG);
1017    case ISD::GlobalTLSAddress:   return LowerGlobalTLSAddress(Op, DAG);
1018    case ISD::JumpTable:          return LowerJumpTable(Op, DAG);
1019    case ISD::SELECT:             return LowerSELECT(Op, DAG);
1020    case ISD::SELECT_CC:          return LowerSELECT_CC(Op, DAG);
1021    case ISD::SETCC:              return LowerSETCC(Op, DAG);
1022    case ISD::VASTART:            return LowerVASTART(Op, DAG);
1023    case ISD::FCOPYSIGN:          return LowerFCOPYSIGN(Op, DAG);
1024    case ISD::FABS:               return LowerFABS(Op, DAG);
1025    case ISD::FRAMEADDR:          return LowerFRAMEADDR(Op, DAG);
1026    case ISD::RETURNADDR:         return LowerRETURNADDR(Op, DAG);
1027    case ISD::MEMBARRIER:         return LowerMEMBARRIER(Op, DAG);
1028    case ISD::ATOMIC_FENCE:       return LowerATOMIC_FENCE(Op, DAG);
1029    case ISD::SHL_PARTS:          return LowerShiftLeftParts(Op, DAG);
1030    case ISD::SRA_PARTS:          return LowerShiftRightParts(Op, DAG, true);
1031    case ISD::SRL_PARTS:          return LowerShiftRightParts(Op, DAG, false);
1032    case ISD::LOAD:               return LowerLOAD(Op, DAG);
1033    case ISD::STORE:              return LowerSTORE(Op, DAG);
1034    case ISD::INTRINSIC_WO_CHAIN: return LowerINTRINSIC_WO_CHAIN(Op, DAG);
1035    case ISD::INTRINSIC_W_CHAIN:  return LowerINTRINSIC_W_CHAIN(Op, DAG);
1036    case ISD::ADD:                return LowerADD(Op, DAG);
1037  }
1038  return SDValue();
1039}
1040
1041//===----------------------------------------------------------------------===//
1042//  Lower helper functions
1043//===----------------------------------------------------------------------===//
1044
1045// AddLiveIn - This helper function adds the specified physical register to the
1046// MachineFunction as a live in value.  It also creates a corresponding
1047// virtual register for it.
1048static unsigned
1049AddLiveIn(MachineFunction &MF, unsigned PReg, const TargetRegisterClass *RC)
1050{
1051  assert(RC->contains(PReg) && "Not the correct regclass!");
1052  unsigned VReg = MF.getRegInfo().createVirtualRegister(RC);
1053  MF.getRegInfo().addLiveIn(PReg, VReg);
1054  return VReg;
1055}
1056
1057// Get fp branch code (not opcode) from condition code.
1058static Mips::FPBranchCode GetFPBranchCodeFromCond(Mips::CondCode CC) {
1059  if (CC >= Mips::FCOND_F && CC <= Mips::FCOND_NGT)
1060    return Mips::BRANCH_T;
1061
1062  assert((CC >= Mips::FCOND_T && CC <= Mips::FCOND_GT) &&
1063         "Invalid CondCode.");
1064
1065  return Mips::BRANCH_F;
1066}
1067
1068/*
1069static MachineBasicBlock* ExpandCondMov(MachineInstr *MI, MachineBasicBlock *BB,
1070                                        DebugLoc dl,
1071                                        const MipsSubtarget *Subtarget,
1072                                        const TargetInstrInfo *TII,
1073                                        bool isFPCmp, unsigned Opc) {
1074  // There is no need to expand CMov instructions if target has
1075  // conditional moves.
1076  if (Subtarget->hasCondMov())
1077    return BB;
1078
1079  // To "insert" a SELECT_CC instruction, we actually have to insert the
1080  // diamond control-flow pattern.  The incoming instruction knows the
1081  // destination vreg to set, the condition code register to branch on, the
1082  // true/false values to select between, and a branch opcode to use.
1083  const BasicBlock *LLVM_BB = BB->getBasicBlock();
1084  MachineFunction::iterator It = BB;
1085  ++It;
1086
1087  //  thisMBB:
1088  //  ...
1089  //   TrueVal = ...
1090  //   setcc r1, r2, r3
1091  //   bNE   r1, r0, copy1MBB
1092  //   fallthrough --> copy0MBB
1093  MachineBasicBlock *thisMBB  = BB;
1094  MachineFunction *F = BB->getParent();
1095  MachineBasicBlock *copy0MBB = F->CreateMachineBasicBlock(LLVM_BB);
1096  MachineBasicBlock *sinkMBB  = F->CreateMachineBasicBlock(LLVM_BB);
1097  F->insert(It, copy0MBB);
1098  F->insert(It, sinkMBB);
1099
1100  // Transfer the remainder of BB and its successor edges to sinkMBB.
1101  sinkMBB->splice(sinkMBB->begin(), BB,
1102                  llvm::next(MachineBasicBlock::iterator(MI)),
1103                  BB->end());
1104  sinkMBB->transferSuccessorsAndUpdatePHIs(BB);
1105
1106  // Next, add the true and fallthrough blocks as its successors.
1107  BB->addSuccessor(copy0MBB);
1108  BB->addSuccessor(sinkMBB);
1109
1110  // Emit the right instruction according to the type of the operands compared
1111  if (isFPCmp)
1112    BuildMI(BB, dl, TII->get(Opc)).addMBB(sinkMBB);
1113  else
1114    BuildMI(BB, dl, TII->get(Opc)).addReg(MI->getOperand(2).getReg())
1115      .addReg(Mips::ZERO).addMBB(sinkMBB);
1116
1117  //  copy0MBB:
1118  //   %FalseValue = ...
1119  //   # fallthrough to sinkMBB
1120  BB = copy0MBB;
1121
1122  // Update machine-CFG edges
1123  BB->addSuccessor(sinkMBB);
1124
1125  //  sinkMBB:
1126  //   %Result = phi [ %TrueValue, thisMBB ], [ %FalseValue, copy0MBB ]
1127  //  ...
1128  BB = sinkMBB;
1129
1130  if (isFPCmp)
1131    BuildMI(*BB, BB->begin(), dl,
1132            TII->get(Mips::PHI), MI->getOperand(0).getReg())
1133      .addReg(MI->getOperand(2).getReg()).addMBB(thisMBB)
1134      .addReg(MI->getOperand(1).getReg()).addMBB(copy0MBB);
1135  else
1136    BuildMI(*BB, BB->begin(), dl,
1137            TII->get(Mips::PHI), MI->getOperand(0).getReg())
1138      .addReg(MI->getOperand(3).getReg()).addMBB(thisMBB)
1139      .addReg(MI->getOperand(1).getReg()).addMBB(copy0MBB);
1140
1141  MI->eraseFromParent();   // The pseudo instruction is gone now.
1142  return BB;
1143}
1144*/
1145
1146MachineBasicBlock *
1147MipsTargetLowering::EmitBPOSGE32(MachineInstr *MI, MachineBasicBlock *BB) const{
1148  // $bb:
1149  //  bposge32_pseudo $vr0
1150  //  =>
1151  // $bb:
1152  //  bposge32 $tbb
1153  // $fbb:
1154  //  li $vr2, 0
1155  //  b $sink
1156  // $tbb:
1157  //  li $vr1, 1
1158  // $sink:
1159  //  $vr0 = phi($vr2, $fbb, $vr1, $tbb)
1160
1161  MachineRegisterInfo &RegInfo = BB->getParent()->getRegInfo();
1162  const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
1163  const TargetRegisterClass *RC = &Mips::CPURegsRegClass;
1164  DebugLoc DL = MI->getDebugLoc();
1165  const BasicBlock *LLVM_BB = BB->getBasicBlock();
1166  MachineFunction::iterator It = llvm::next(MachineFunction::iterator(BB));
1167  MachineFunction *F = BB->getParent();
1168  MachineBasicBlock *FBB = F->CreateMachineBasicBlock(LLVM_BB);
1169  MachineBasicBlock *TBB = F->CreateMachineBasicBlock(LLVM_BB);
1170  MachineBasicBlock *Sink  = F->CreateMachineBasicBlock(LLVM_BB);
1171  F->insert(It, FBB);
1172  F->insert(It, TBB);
1173  F->insert(It, Sink);
1174
1175  // Transfer the remainder of BB and its successor edges to Sink.
1176  Sink->splice(Sink->begin(), BB, llvm::next(MachineBasicBlock::iterator(MI)),
1177               BB->end());
1178  Sink->transferSuccessorsAndUpdatePHIs(BB);
1179
1180  // Add successors.
1181  BB->addSuccessor(FBB);
1182  BB->addSuccessor(TBB);
1183  FBB->addSuccessor(Sink);
1184  TBB->addSuccessor(Sink);
1185
1186  // Insert the real bposge32 instruction to $BB.
1187  BuildMI(BB, DL, TII->get(Mips::BPOSGE32)).addMBB(TBB);
1188
1189  // Fill $FBB.
1190  unsigned VR2 = RegInfo.createVirtualRegister(RC);
1191  BuildMI(*FBB, FBB->end(), DL, TII->get(Mips::ADDiu), VR2)
1192    .addReg(Mips::ZERO).addImm(0);
1193  BuildMI(*FBB, FBB->end(), DL, TII->get(Mips::B)).addMBB(Sink);
1194
1195  // Fill $TBB.
1196  unsigned VR1 = RegInfo.createVirtualRegister(RC);
1197  BuildMI(*TBB, TBB->end(), DL, TII->get(Mips::ADDiu), VR1)
1198    .addReg(Mips::ZERO).addImm(1);
1199
1200  // Insert phi function to $Sink.
1201  BuildMI(*Sink, Sink->begin(), DL, TII->get(Mips::PHI),
1202          MI->getOperand(0).getReg())
1203    .addReg(VR2).addMBB(FBB).addReg(VR1).addMBB(TBB);
1204
1205  MI->eraseFromParent();   // The pseudo instruction is gone now.
1206  return Sink;
1207}
1208
1209MachineBasicBlock *
1210MipsTargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
1211                                                MachineBasicBlock *BB) const {
1212  switch (MI->getOpcode()) {
1213  default: llvm_unreachable("Unexpected instr type to insert");
1214  case Mips::ATOMIC_LOAD_ADD_I8:
1215  case Mips::ATOMIC_LOAD_ADD_I8_P8:
1216    return EmitAtomicBinaryPartword(MI, BB, 1, Mips::ADDu);
1217  case Mips::ATOMIC_LOAD_ADD_I16:
1218  case Mips::ATOMIC_LOAD_ADD_I16_P8:
1219    return EmitAtomicBinaryPartword(MI, BB, 2, Mips::ADDu);
1220  case Mips::ATOMIC_LOAD_ADD_I32:
1221  case Mips::ATOMIC_LOAD_ADD_I32_P8:
1222    return EmitAtomicBinary(MI, BB, 4, Mips::ADDu);
1223  case Mips::ATOMIC_LOAD_ADD_I64:
1224  case Mips::ATOMIC_LOAD_ADD_I64_P8:
1225    return EmitAtomicBinary(MI, BB, 8, Mips::DADDu);
1226
1227  case Mips::ATOMIC_LOAD_AND_I8:
1228  case Mips::ATOMIC_LOAD_AND_I8_P8:
1229    return EmitAtomicBinaryPartword(MI, BB, 1, Mips::AND);
1230  case Mips::ATOMIC_LOAD_AND_I16:
1231  case Mips::ATOMIC_LOAD_AND_I16_P8:
1232    return EmitAtomicBinaryPartword(MI, BB, 2, Mips::AND);
1233  case Mips::ATOMIC_LOAD_AND_I32:
1234  case Mips::ATOMIC_LOAD_AND_I32_P8:
1235    return EmitAtomicBinary(MI, BB, 4, Mips::AND);
1236  case Mips::ATOMIC_LOAD_AND_I64:
1237  case Mips::ATOMIC_LOAD_AND_I64_P8:
1238    return EmitAtomicBinary(MI, BB, 8, Mips::AND64);
1239
1240  case Mips::ATOMIC_LOAD_OR_I8:
1241  case Mips::ATOMIC_LOAD_OR_I8_P8:
1242    return EmitAtomicBinaryPartword(MI, BB, 1, Mips::OR);
1243  case Mips::ATOMIC_LOAD_OR_I16:
1244  case Mips::ATOMIC_LOAD_OR_I16_P8:
1245    return EmitAtomicBinaryPartword(MI, BB, 2, Mips::OR);
1246  case Mips::ATOMIC_LOAD_OR_I32:
1247  case Mips::ATOMIC_LOAD_OR_I32_P8:
1248    return EmitAtomicBinary(MI, BB, 4, Mips::OR);
1249  case Mips::ATOMIC_LOAD_OR_I64:
1250  case Mips::ATOMIC_LOAD_OR_I64_P8:
1251    return EmitAtomicBinary(MI, BB, 8, Mips::OR64);
1252
1253  case Mips::ATOMIC_LOAD_XOR_I8:
1254  case Mips::ATOMIC_LOAD_XOR_I8_P8:
1255    return EmitAtomicBinaryPartword(MI, BB, 1, Mips::XOR);
1256  case Mips::ATOMIC_LOAD_XOR_I16:
1257  case Mips::ATOMIC_LOAD_XOR_I16_P8:
1258    return EmitAtomicBinaryPartword(MI, BB, 2, Mips::XOR);
1259  case Mips::ATOMIC_LOAD_XOR_I32:
1260  case Mips::ATOMIC_LOAD_XOR_I32_P8:
1261    return EmitAtomicBinary(MI, BB, 4, Mips::XOR);
1262  case Mips::ATOMIC_LOAD_XOR_I64:
1263  case Mips::ATOMIC_LOAD_XOR_I64_P8:
1264    return EmitAtomicBinary(MI, BB, 8, Mips::XOR64);
1265
1266  case Mips::ATOMIC_LOAD_NAND_I8:
1267  case Mips::ATOMIC_LOAD_NAND_I8_P8:
1268    return EmitAtomicBinaryPartword(MI, BB, 1, 0, true);
1269  case Mips::ATOMIC_LOAD_NAND_I16:
1270  case Mips::ATOMIC_LOAD_NAND_I16_P8:
1271    return EmitAtomicBinaryPartword(MI, BB, 2, 0, true);
1272  case Mips::ATOMIC_LOAD_NAND_I32:
1273  case Mips::ATOMIC_LOAD_NAND_I32_P8:
1274    return EmitAtomicBinary(MI, BB, 4, 0, true);
1275  case Mips::ATOMIC_LOAD_NAND_I64:
1276  case Mips::ATOMIC_LOAD_NAND_I64_P8:
1277    return EmitAtomicBinary(MI, BB, 8, 0, true);
1278
1279  case Mips::ATOMIC_LOAD_SUB_I8:
1280  case Mips::ATOMIC_LOAD_SUB_I8_P8:
1281    return EmitAtomicBinaryPartword(MI, BB, 1, Mips::SUBu);
1282  case Mips::ATOMIC_LOAD_SUB_I16:
1283  case Mips::ATOMIC_LOAD_SUB_I16_P8:
1284    return EmitAtomicBinaryPartword(MI, BB, 2, Mips::SUBu);
1285  case Mips::ATOMIC_LOAD_SUB_I32:
1286  case Mips::ATOMIC_LOAD_SUB_I32_P8:
1287    return EmitAtomicBinary(MI, BB, 4, Mips::SUBu);
1288  case Mips::ATOMIC_LOAD_SUB_I64:
1289  case Mips::ATOMIC_LOAD_SUB_I64_P8:
1290    return EmitAtomicBinary(MI, BB, 8, Mips::DSUBu);
1291
1292  case Mips::ATOMIC_SWAP_I8:
1293  case Mips::ATOMIC_SWAP_I8_P8:
1294    return EmitAtomicBinaryPartword(MI, BB, 1, 0);
1295  case Mips::ATOMIC_SWAP_I16:
1296  case Mips::ATOMIC_SWAP_I16_P8:
1297    return EmitAtomicBinaryPartword(MI, BB, 2, 0);
1298  case Mips::ATOMIC_SWAP_I32:
1299  case Mips::ATOMIC_SWAP_I32_P8:
1300    return EmitAtomicBinary(MI, BB, 4, 0);
1301  case Mips::ATOMIC_SWAP_I64:
1302  case Mips::ATOMIC_SWAP_I64_P8:
1303    return EmitAtomicBinary(MI, BB, 8, 0);
1304
1305  case Mips::ATOMIC_CMP_SWAP_I8:
1306  case Mips::ATOMIC_CMP_SWAP_I8_P8:
1307    return EmitAtomicCmpSwapPartword(MI, BB, 1);
1308  case Mips::ATOMIC_CMP_SWAP_I16:
1309  case Mips::ATOMIC_CMP_SWAP_I16_P8:
1310    return EmitAtomicCmpSwapPartword(MI, BB, 2);
1311  case Mips::ATOMIC_CMP_SWAP_I32:
1312  case Mips::ATOMIC_CMP_SWAP_I32_P8:
1313    return EmitAtomicCmpSwap(MI, BB, 4);
1314  case Mips::ATOMIC_CMP_SWAP_I64:
1315  case Mips::ATOMIC_CMP_SWAP_I64_P8:
1316    return EmitAtomicCmpSwap(MI, BB, 8);
1317  case Mips::BPOSGE32_PSEUDO:
1318    return EmitBPOSGE32(MI, BB);
1319  }
1320}
1321
1322// This function also handles Mips::ATOMIC_SWAP_I32 (when BinOpcode == 0), and
1323// Mips::ATOMIC_LOAD_NAND_I32 (when Nand == true)
1324MachineBasicBlock *
1325MipsTargetLowering::EmitAtomicBinary(MachineInstr *MI, MachineBasicBlock *BB,
1326                                     unsigned Size, unsigned BinOpcode,
1327                                     bool Nand) const {
1328  assert((Size == 4 || Size == 8) && "Unsupported size for EmitAtomicBinary.");
1329
1330  MachineFunction *MF = BB->getParent();
1331  MachineRegisterInfo &RegInfo = MF->getRegInfo();
1332  const TargetRegisterClass *RC = getRegClassFor(MVT::getIntegerVT(Size * 8));
1333  const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
1334  DebugLoc dl = MI->getDebugLoc();
1335  unsigned LL, SC, AND, NOR, ZERO, BEQ;
1336
1337  if (Size == 4) {
1338    LL = IsN64 ? Mips::LL_P8 : Mips::LL;
1339    SC = IsN64 ? Mips::SC_P8 : Mips::SC;
1340    AND = Mips::AND;
1341    NOR = Mips::NOR;
1342    ZERO = Mips::ZERO;
1343    BEQ = Mips::BEQ;
1344  }
1345  else {
1346    LL = IsN64 ? Mips::LLD_P8 : Mips::LLD;
1347    SC = IsN64 ? Mips::SCD_P8 : Mips::SCD;
1348    AND = Mips::AND64;
1349    NOR = Mips::NOR64;
1350    ZERO = Mips::ZERO_64;
1351    BEQ = Mips::BEQ64;
1352  }
1353
1354  unsigned OldVal = MI->getOperand(0).getReg();
1355  unsigned Ptr = MI->getOperand(1).getReg();
1356  unsigned Incr = MI->getOperand(2).getReg();
1357
1358  unsigned StoreVal = RegInfo.createVirtualRegister(RC);
1359  unsigned AndRes = RegInfo.createVirtualRegister(RC);
1360  unsigned Success = RegInfo.createVirtualRegister(RC);
1361
1362  // insert new blocks after the current block
1363  const BasicBlock *LLVM_BB = BB->getBasicBlock();
1364  MachineBasicBlock *loopMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1365  MachineBasicBlock *exitMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1366  MachineFunction::iterator It = BB;
1367  ++It;
1368  MF->insert(It, loopMBB);
1369  MF->insert(It, exitMBB);
1370
1371  // Transfer the remainder of BB and its successor edges to exitMBB.
1372  exitMBB->splice(exitMBB->begin(), BB,
1373                  llvm::next(MachineBasicBlock::iterator(MI)),
1374                  BB->end());
1375  exitMBB->transferSuccessorsAndUpdatePHIs(BB);
1376
1377  //  thisMBB:
1378  //    ...
1379  //    fallthrough --> loopMBB
1380  BB->addSuccessor(loopMBB);
1381  loopMBB->addSuccessor(loopMBB);
1382  loopMBB->addSuccessor(exitMBB);
1383
1384  //  loopMBB:
1385  //    ll oldval, 0(ptr)
1386  //    <binop> storeval, oldval, incr
1387  //    sc success, storeval, 0(ptr)
1388  //    beq success, $0, loopMBB
1389  BB = loopMBB;
1390  BuildMI(BB, dl, TII->get(LL), OldVal).addReg(Ptr).addImm(0);
1391  if (Nand) {
1392    //  and andres, oldval, incr
1393    //  nor storeval, $0, andres
1394    BuildMI(BB, dl, TII->get(AND), AndRes).addReg(OldVal).addReg(Incr);
1395    BuildMI(BB, dl, TII->get(NOR), StoreVal).addReg(ZERO).addReg(AndRes);
1396  } else if (BinOpcode) {
1397    //  <binop> storeval, oldval, incr
1398    BuildMI(BB, dl, TII->get(BinOpcode), StoreVal).addReg(OldVal).addReg(Incr);
1399  } else {
1400    StoreVal = Incr;
1401  }
1402  BuildMI(BB, dl, TII->get(SC), Success).addReg(StoreVal).addReg(Ptr).addImm(0);
1403  BuildMI(BB, dl, TII->get(BEQ)).addReg(Success).addReg(ZERO).addMBB(loopMBB);
1404
1405  MI->eraseFromParent();   // The instruction is gone now.
1406
1407  return exitMBB;
1408}
1409
1410MachineBasicBlock *
1411MipsTargetLowering::EmitAtomicBinaryPartword(MachineInstr *MI,
1412                                             MachineBasicBlock *BB,
1413                                             unsigned Size, unsigned BinOpcode,
1414                                             bool Nand) const {
1415  assert((Size == 1 || Size == 2) &&
1416      "Unsupported size for EmitAtomicBinaryPartial.");
1417
1418  MachineFunction *MF = BB->getParent();
1419  MachineRegisterInfo &RegInfo = MF->getRegInfo();
1420  const TargetRegisterClass *RC = getRegClassFor(MVT::i32);
1421  const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
1422  DebugLoc dl = MI->getDebugLoc();
1423  unsigned LL = IsN64 ? Mips::LL_P8 : Mips::LL;
1424  unsigned SC = IsN64 ? Mips::SC_P8 : Mips::SC;
1425
1426  unsigned Dest = MI->getOperand(0).getReg();
1427  unsigned Ptr = MI->getOperand(1).getReg();
1428  unsigned Incr = MI->getOperand(2).getReg();
1429
1430  unsigned AlignedAddr = RegInfo.createVirtualRegister(RC);
1431  unsigned ShiftAmt = RegInfo.createVirtualRegister(RC);
1432  unsigned Mask = RegInfo.createVirtualRegister(RC);
1433  unsigned Mask2 = RegInfo.createVirtualRegister(RC);
1434  unsigned NewVal = RegInfo.createVirtualRegister(RC);
1435  unsigned OldVal = RegInfo.createVirtualRegister(RC);
1436  unsigned Incr2 = RegInfo.createVirtualRegister(RC);
1437  unsigned MaskLSB2 = RegInfo.createVirtualRegister(RC);
1438  unsigned PtrLSB2 = RegInfo.createVirtualRegister(RC);
1439  unsigned MaskUpper = RegInfo.createVirtualRegister(RC);
1440  unsigned AndRes = RegInfo.createVirtualRegister(RC);
1441  unsigned BinOpRes = RegInfo.createVirtualRegister(RC);
1442  unsigned MaskedOldVal0 = RegInfo.createVirtualRegister(RC);
1443  unsigned StoreVal = RegInfo.createVirtualRegister(RC);
1444  unsigned MaskedOldVal1 = RegInfo.createVirtualRegister(RC);
1445  unsigned SrlRes = RegInfo.createVirtualRegister(RC);
1446  unsigned SllRes = RegInfo.createVirtualRegister(RC);
1447  unsigned Success = RegInfo.createVirtualRegister(RC);
1448
1449  // insert new blocks after the current block
1450  const BasicBlock *LLVM_BB = BB->getBasicBlock();
1451  MachineBasicBlock *loopMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1452  MachineBasicBlock *sinkMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1453  MachineBasicBlock *exitMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1454  MachineFunction::iterator It = BB;
1455  ++It;
1456  MF->insert(It, loopMBB);
1457  MF->insert(It, sinkMBB);
1458  MF->insert(It, exitMBB);
1459
1460  // Transfer the remainder of BB and its successor edges to exitMBB.
1461  exitMBB->splice(exitMBB->begin(), BB,
1462                  llvm::next(MachineBasicBlock::iterator(MI)), BB->end());
1463  exitMBB->transferSuccessorsAndUpdatePHIs(BB);
1464
1465  BB->addSuccessor(loopMBB);
1466  loopMBB->addSuccessor(loopMBB);
1467  loopMBB->addSuccessor(sinkMBB);
1468  sinkMBB->addSuccessor(exitMBB);
1469
1470  //  thisMBB:
1471  //    addiu   masklsb2,$0,-4                # 0xfffffffc
1472  //    and     alignedaddr,ptr,masklsb2
1473  //    andi    ptrlsb2,ptr,3
1474  //    sll     shiftamt,ptrlsb2,3
1475  //    ori     maskupper,$0,255               # 0xff
1476  //    sll     mask,maskupper,shiftamt
1477  //    nor     mask2,$0,mask
1478  //    sll     incr2,incr,shiftamt
1479
1480  int64_t MaskImm = (Size == 1) ? 255 : 65535;
1481  BuildMI(BB, dl, TII->get(Mips::ADDiu), MaskLSB2)
1482    .addReg(Mips::ZERO).addImm(-4);
1483  BuildMI(BB, dl, TII->get(Mips::AND), AlignedAddr)
1484    .addReg(Ptr).addReg(MaskLSB2);
1485  BuildMI(BB, dl, TII->get(Mips::ANDi), PtrLSB2).addReg(Ptr).addImm(3);
1486  BuildMI(BB, dl, TII->get(Mips::SLL), ShiftAmt).addReg(PtrLSB2).addImm(3);
1487  BuildMI(BB, dl, TII->get(Mips::ORi), MaskUpper)
1488    .addReg(Mips::ZERO).addImm(MaskImm);
1489  BuildMI(BB, dl, TII->get(Mips::SLLV), Mask)
1490    .addReg(ShiftAmt).addReg(MaskUpper);
1491  BuildMI(BB, dl, TII->get(Mips::NOR), Mask2).addReg(Mips::ZERO).addReg(Mask);
1492  BuildMI(BB, dl, TII->get(Mips::SLLV), Incr2).addReg(ShiftAmt).addReg(Incr);
1493
1494  // atomic.load.binop
1495  // loopMBB:
1496  //   ll      oldval,0(alignedaddr)
1497  //   binop   binopres,oldval,incr2
1498  //   and     newval,binopres,mask
1499  //   and     maskedoldval0,oldval,mask2
1500  //   or      storeval,maskedoldval0,newval
1501  //   sc      success,storeval,0(alignedaddr)
1502  //   beq     success,$0,loopMBB
1503
1504  // atomic.swap
1505  // loopMBB:
1506  //   ll      oldval,0(alignedaddr)
1507  //   and     newval,incr2,mask
1508  //   and     maskedoldval0,oldval,mask2
1509  //   or      storeval,maskedoldval0,newval
1510  //   sc      success,storeval,0(alignedaddr)
1511  //   beq     success,$0,loopMBB
1512
1513  BB = loopMBB;
1514  BuildMI(BB, dl, TII->get(LL), OldVal).addReg(AlignedAddr).addImm(0);
1515  if (Nand) {
1516    //  and andres, oldval, incr2
1517    //  nor binopres, $0, andres
1518    //  and newval, binopres, mask
1519    BuildMI(BB, dl, TII->get(Mips::AND), AndRes).addReg(OldVal).addReg(Incr2);
1520    BuildMI(BB, dl, TII->get(Mips::NOR), BinOpRes)
1521      .addReg(Mips::ZERO).addReg(AndRes);
1522    BuildMI(BB, dl, TII->get(Mips::AND), NewVal).addReg(BinOpRes).addReg(Mask);
1523  } else if (BinOpcode) {
1524    //  <binop> binopres, oldval, incr2
1525    //  and newval, binopres, mask
1526    BuildMI(BB, dl, TII->get(BinOpcode), BinOpRes).addReg(OldVal).addReg(Incr2);
1527    BuildMI(BB, dl, TII->get(Mips::AND), NewVal).addReg(BinOpRes).addReg(Mask);
1528  } else {// atomic.swap
1529    //  and newval, incr2, mask
1530    BuildMI(BB, dl, TII->get(Mips::AND), NewVal).addReg(Incr2).addReg(Mask);
1531  }
1532
1533  BuildMI(BB, dl, TII->get(Mips::AND), MaskedOldVal0)
1534    .addReg(OldVal).addReg(Mask2);
1535  BuildMI(BB, dl, TII->get(Mips::OR), StoreVal)
1536    .addReg(MaskedOldVal0).addReg(NewVal);
1537  BuildMI(BB, dl, TII->get(SC), Success)
1538    .addReg(StoreVal).addReg(AlignedAddr).addImm(0);
1539  BuildMI(BB, dl, TII->get(Mips::BEQ))
1540    .addReg(Success).addReg(Mips::ZERO).addMBB(loopMBB);
1541
1542  //  sinkMBB:
1543  //    and     maskedoldval1,oldval,mask
1544  //    srl     srlres,maskedoldval1,shiftamt
1545  //    sll     sllres,srlres,24
1546  //    sra     dest,sllres,24
1547  BB = sinkMBB;
1548  int64_t ShiftImm = (Size == 1) ? 24 : 16;
1549
1550  BuildMI(BB, dl, TII->get(Mips::AND), MaskedOldVal1)
1551    .addReg(OldVal).addReg(Mask);
1552  BuildMI(BB, dl, TII->get(Mips::SRLV), SrlRes)
1553      .addReg(ShiftAmt).addReg(MaskedOldVal1);
1554  BuildMI(BB, dl, TII->get(Mips::SLL), SllRes)
1555      .addReg(SrlRes).addImm(ShiftImm);
1556  BuildMI(BB, dl, TII->get(Mips::SRA), Dest)
1557      .addReg(SllRes).addImm(ShiftImm);
1558
1559  MI->eraseFromParent();   // The instruction is gone now.
1560
1561  return exitMBB;
1562}
1563
1564MachineBasicBlock *
1565MipsTargetLowering::EmitAtomicCmpSwap(MachineInstr *MI,
1566                                      MachineBasicBlock *BB,
1567                                      unsigned Size) const {
1568  assert((Size == 4 || Size == 8) && "Unsupported size for EmitAtomicCmpSwap.");
1569
1570  MachineFunction *MF = BB->getParent();
1571  MachineRegisterInfo &RegInfo = MF->getRegInfo();
1572  const TargetRegisterClass *RC = getRegClassFor(MVT::getIntegerVT(Size * 8));
1573  const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
1574  DebugLoc dl = MI->getDebugLoc();
1575  unsigned LL, SC, ZERO, BNE, BEQ;
1576
1577  if (Size == 4) {
1578    LL = IsN64 ? Mips::LL_P8 : Mips::LL;
1579    SC = IsN64 ? Mips::SC_P8 : Mips::SC;
1580    ZERO = Mips::ZERO;
1581    BNE = Mips::BNE;
1582    BEQ = Mips::BEQ;
1583  }
1584  else {
1585    LL = IsN64 ? Mips::LLD_P8 : Mips::LLD;
1586    SC = IsN64 ? Mips::SCD_P8 : Mips::SCD;
1587    ZERO = Mips::ZERO_64;
1588    BNE = Mips::BNE64;
1589    BEQ = Mips::BEQ64;
1590  }
1591
1592  unsigned Dest    = MI->getOperand(0).getReg();
1593  unsigned Ptr     = MI->getOperand(1).getReg();
1594  unsigned OldVal  = MI->getOperand(2).getReg();
1595  unsigned NewVal  = MI->getOperand(3).getReg();
1596
1597  unsigned Success = RegInfo.createVirtualRegister(RC);
1598
1599  // insert new blocks after the current block
1600  const BasicBlock *LLVM_BB = BB->getBasicBlock();
1601  MachineBasicBlock *loop1MBB = MF->CreateMachineBasicBlock(LLVM_BB);
1602  MachineBasicBlock *loop2MBB = MF->CreateMachineBasicBlock(LLVM_BB);
1603  MachineBasicBlock *exitMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1604  MachineFunction::iterator It = BB;
1605  ++It;
1606  MF->insert(It, loop1MBB);
1607  MF->insert(It, loop2MBB);
1608  MF->insert(It, exitMBB);
1609
1610  // Transfer the remainder of BB and its successor edges to exitMBB.
1611  exitMBB->splice(exitMBB->begin(), BB,
1612                  llvm::next(MachineBasicBlock::iterator(MI)), BB->end());
1613  exitMBB->transferSuccessorsAndUpdatePHIs(BB);
1614
1615  //  thisMBB:
1616  //    ...
1617  //    fallthrough --> loop1MBB
1618  BB->addSuccessor(loop1MBB);
1619  loop1MBB->addSuccessor(exitMBB);
1620  loop1MBB->addSuccessor(loop2MBB);
1621  loop2MBB->addSuccessor(loop1MBB);
1622  loop2MBB->addSuccessor(exitMBB);
1623
1624  // loop1MBB:
1625  //   ll dest, 0(ptr)
1626  //   bne dest, oldval, exitMBB
1627  BB = loop1MBB;
1628  BuildMI(BB, dl, TII->get(LL), Dest).addReg(Ptr).addImm(0);
1629  BuildMI(BB, dl, TII->get(BNE))
1630    .addReg(Dest).addReg(OldVal).addMBB(exitMBB);
1631
1632  // loop2MBB:
1633  //   sc success, newval, 0(ptr)
1634  //   beq success, $0, loop1MBB
1635  BB = loop2MBB;
1636  BuildMI(BB, dl, TII->get(SC), Success)
1637    .addReg(NewVal).addReg(Ptr).addImm(0);
1638  BuildMI(BB, dl, TII->get(BEQ))
1639    .addReg(Success).addReg(ZERO).addMBB(loop1MBB);
1640
1641  MI->eraseFromParent();   // The instruction is gone now.
1642
1643  return exitMBB;
1644}
1645
1646MachineBasicBlock *
1647MipsTargetLowering::EmitAtomicCmpSwapPartword(MachineInstr *MI,
1648                                              MachineBasicBlock *BB,
1649                                              unsigned Size) const {
1650  assert((Size == 1 || Size == 2) &&
1651      "Unsupported size for EmitAtomicCmpSwapPartial.");
1652
1653  MachineFunction *MF = BB->getParent();
1654  MachineRegisterInfo &RegInfo = MF->getRegInfo();
1655  const TargetRegisterClass *RC = getRegClassFor(MVT::i32);
1656  const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
1657  DebugLoc dl = MI->getDebugLoc();
1658  unsigned LL = IsN64 ? Mips::LL_P8 : Mips::LL;
1659  unsigned SC = IsN64 ? Mips::SC_P8 : Mips::SC;
1660
1661  unsigned Dest    = MI->getOperand(0).getReg();
1662  unsigned Ptr     = MI->getOperand(1).getReg();
1663  unsigned CmpVal  = MI->getOperand(2).getReg();
1664  unsigned NewVal  = MI->getOperand(3).getReg();
1665
1666  unsigned AlignedAddr = RegInfo.createVirtualRegister(RC);
1667  unsigned ShiftAmt = RegInfo.createVirtualRegister(RC);
1668  unsigned Mask = RegInfo.createVirtualRegister(RC);
1669  unsigned Mask2 = RegInfo.createVirtualRegister(RC);
1670  unsigned ShiftedCmpVal = RegInfo.createVirtualRegister(RC);
1671  unsigned OldVal = RegInfo.createVirtualRegister(RC);
1672  unsigned MaskedOldVal0 = RegInfo.createVirtualRegister(RC);
1673  unsigned ShiftedNewVal = RegInfo.createVirtualRegister(RC);
1674  unsigned MaskLSB2 = RegInfo.createVirtualRegister(RC);
1675  unsigned PtrLSB2 = RegInfo.createVirtualRegister(RC);
1676  unsigned MaskUpper = RegInfo.createVirtualRegister(RC);
1677  unsigned MaskedCmpVal = RegInfo.createVirtualRegister(RC);
1678  unsigned MaskedNewVal = RegInfo.createVirtualRegister(RC);
1679  unsigned MaskedOldVal1 = RegInfo.createVirtualRegister(RC);
1680  unsigned StoreVal = RegInfo.createVirtualRegister(RC);
1681  unsigned SrlRes = RegInfo.createVirtualRegister(RC);
1682  unsigned SllRes = RegInfo.createVirtualRegister(RC);
1683  unsigned Success = RegInfo.createVirtualRegister(RC);
1684
1685  // insert new blocks after the current block
1686  const BasicBlock *LLVM_BB = BB->getBasicBlock();
1687  MachineBasicBlock *loop1MBB = MF->CreateMachineBasicBlock(LLVM_BB);
1688  MachineBasicBlock *loop2MBB = MF->CreateMachineBasicBlock(LLVM_BB);
1689  MachineBasicBlock *sinkMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1690  MachineBasicBlock *exitMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1691  MachineFunction::iterator It = BB;
1692  ++It;
1693  MF->insert(It, loop1MBB);
1694  MF->insert(It, loop2MBB);
1695  MF->insert(It, sinkMBB);
1696  MF->insert(It, exitMBB);
1697
1698  // Transfer the remainder of BB and its successor edges to exitMBB.
1699  exitMBB->splice(exitMBB->begin(), BB,
1700                  llvm::next(MachineBasicBlock::iterator(MI)), BB->end());
1701  exitMBB->transferSuccessorsAndUpdatePHIs(BB);
1702
1703  BB->addSuccessor(loop1MBB);
1704  loop1MBB->addSuccessor(sinkMBB);
1705  loop1MBB->addSuccessor(loop2MBB);
1706  loop2MBB->addSuccessor(loop1MBB);
1707  loop2MBB->addSuccessor(sinkMBB);
1708  sinkMBB->addSuccessor(exitMBB);
1709
1710  // FIXME: computation of newval2 can be moved to loop2MBB.
1711  //  thisMBB:
1712  //    addiu   masklsb2,$0,-4                # 0xfffffffc
1713  //    and     alignedaddr,ptr,masklsb2
1714  //    andi    ptrlsb2,ptr,3
1715  //    sll     shiftamt,ptrlsb2,3
1716  //    ori     maskupper,$0,255               # 0xff
1717  //    sll     mask,maskupper,shiftamt
1718  //    nor     mask2,$0,mask
1719  //    andi    maskedcmpval,cmpval,255
1720  //    sll     shiftedcmpval,maskedcmpval,shiftamt
1721  //    andi    maskednewval,newval,255
1722  //    sll     shiftednewval,maskednewval,shiftamt
1723  int64_t MaskImm = (Size == 1) ? 255 : 65535;
1724  BuildMI(BB, dl, TII->get(Mips::ADDiu), MaskLSB2)
1725    .addReg(Mips::ZERO).addImm(-4);
1726  BuildMI(BB, dl, TII->get(Mips::AND), AlignedAddr)
1727    .addReg(Ptr).addReg(MaskLSB2);
1728  BuildMI(BB, dl, TII->get(Mips::ANDi), PtrLSB2).addReg(Ptr).addImm(3);
1729  BuildMI(BB, dl, TII->get(Mips::SLL), ShiftAmt).addReg(PtrLSB2).addImm(3);
1730  BuildMI(BB, dl, TII->get(Mips::ORi), MaskUpper)
1731    .addReg(Mips::ZERO).addImm(MaskImm);
1732  BuildMI(BB, dl, TII->get(Mips::SLLV), Mask)
1733    .addReg(ShiftAmt).addReg(MaskUpper);
1734  BuildMI(BB, dl, TII->get(Mips::NOR), Mask2).addReg(Mips::ZERO).addReg(Mask);
1735  BuildMI(BB, dl, TII->get(Mips::ANDi), MaskedCmpVal)
1736    .addReg(CmpVal).addImm(MaskImm);
1737  BuildMI(BB, dl, TII->get(Mips::SLLV), ShiftedCmpVal)
1738    .addReg(ShiftAmt).addReg(MaskedCmpVal);
1739  BuildMI(BB, dl, TII->get(Mips::ANDi), MaskedNewVal)
1740    .addReg(NewVal).addImm(MaskImm);
1741  BuildMI(BB, dl, TII->get(Mips::SLLV), ShiftedNewVal)
1742    .addReg(ShiftAmt).addReg(MaskedNewVal);
1743
1744  //  loop1MBB:
1745  //    ll      oldval,0(alginedaddr)
1746  //    and     maskedoldval0,oldval,mask
1747  //    bne     maskedoldval0,shiftedcmpval,sinkMBB
1748  BB = loop1MBB;
1749  BuildMI(BB, dl, TII->get(LL), OldVal).addReg(AlignedAddr).addImm(0);
1750  BuildMI(BB, dl, TII->get(Mips::AND), MaskedOldVal0)
1751    .addReg(OldVal).addReg(Mask);
1752  BuildMI(BB, dl, TII->get(Mips::BNE))
1753    .addReg(MaskedOldVal0).addReg(ShiftedCmpVal).addMBB(sinkMBB);
1754
1755  //  loop2MBB:
1756  //    and     maskedoldval1,oldval,mask2
1757  //    or      storeval,maskedoldval1,shiftednewval
1758  //    sc      success,storeval,0(alignedaddr)
1759  //    beq     success,$0,loop1MBB
1760  BB = loop2MBB;
1761  BuildMI(BB, dl, TII->get(Mips::AND), MaskedOldVal1)
1762    .addReg(OldVal).addReg(Mask2);
1763  BuildMI(BB, dl, TII->get(Mips::OR), StoreVal)
1764    .addReg(MaskedOldVal1).addReg(ShiftedNewVal);
1765  BuildMI(BB, dl, TII->get(SC), Success)
1766      .addReg(StoreVal).addReg(AlignedAddr).addImm(0);
1767  BuildMI(BB, dl, TII->get(Mips::BEQ))
1768      .addReg(Success).addReg(Mips::ZERO).addMBB(loop1MBB);
1769
1770  //  sinkMBB:
1771  //    srl     srlres,maskedoldval0,shiftamt
1772  //    sll     sllres,srlres,24
1773  //    sra     dest,sllres,24
1774  BB = sinkMBB;
1775  int64_t ShiftImm = (Size == 1) ? 24 : 16;
1776
1777  BuildMI(BB, dl, TII->get(Mips::SRLV), SrlRes)
1778      .addReg(ShiftAmt).addReg(MaskedOldVal0);
1779  BuildMI(BB, dl, TII->get(Mips::SLL), SllRes)
1780      .addReg(SrlRes).addImm(ShiftImm);
1781  BuildMI(BB, dl, TII->get(Mips::SRA), Dest)
1782      .addReg(SllRes).addImm(ShiftImm);
1783
1784  MI->eraseFromParent();   // The instruction is gone now.
1785
1786  return exitMBB;
1787}
1788
1789//===----------------------------------------------------------------------===//
1790//  Misc Lower Operation implementation
1791//===----------------------------------------------------------------------===//
1792SDValue MipsTargetLowering::
1793LowerBRCOND(SDValue Op, SelectionDAG &DAG) const
1794{
1795  // The first operand is the chain, the second is the condition, the third is
1796  // the block to branch to if the condition is true.
1797  SDValue Chain = Op.getOperand(0);
1798  SDValue Dest = Op.getOperand(2);
1799  DebugLoc dl = Op.getDebugLoc();
1800
1801  SDValue CondRes = CreateFPCmp(DAG, Op.getOperand(1));
1802
1803  // Return if flag is not set by a floating point comparison.
1804  if (CondRes.getOpcode() != MipsISD::FPCmp)
1805    return Op;
1806
1807  SDValue CCNode  = CondRes.getOperand(2);
1808  Mips::CondCode CC =
1809    (Mips::CondCode)cast<ConstantSDNode>(CCNode)->getZExtValue();
1810  SDValue BrCode = DAG.getConstant(GetFPBranchCodeFromCond(CC), MVT::i32);
1811
1812  return DAG.getNode(MipsISD::FPBrcond, dl, Op.getValueType(), Chain, BrCode,
1813                     Dest, CondRes);
1814}
1815
1816SDValue MipsTargetLowering::
1817LowerSELECT(SDValue Op, SelectionDAG &DAG) const
1818{
1819  SDValue Cond = CreateFPCmp(DAG, Op.getOperand(0));
1820
1821  // Return if flag is not set by a floating point comparison.
1822  if (Cond.getOpcode() != MipsISD::FPCmp)
1823    return Op;
1824
1825  return CreateCMovFP(DAG, Cond, Op.getOperand(1), Op.getOperand(2),
1826                      Op.getDebugLoc());
1827}
1828
1829SDValue MipsTargetLowering::
1830LowerSELECT_CC(SDValue Op, SelectionDAG &DAG) const
1831{
1832  DebugLoc DL = Op.getDebugLoc();
1833  EVT Ty = Op.getOperand(0).getValueType();
1834  SDValue Cond = DAG.getNode(ISD::SETCC, DL, getSetCCResultType(Ty),
1835                             Op.getOperand(0), Op.getOperand(1),
1836                             Op.getOperand(4));
1837
1838  return DAG.getNode(ISD::SELECT, DL, Op.getValueType(), Cond, Op.getOperand(2),
1839                     Op.getOperand(3));
1840}
1841
1842SDValue MipsTargetLowering::LowerSETCC(SDValue Op, SelectionDAG &DAG) const {
1843  SDValue Cond = CreateFPCmp(DAG, Op);
1844
1845  assert(Cond.getOpcode() == MipsISD::FPCmp &&
1846         "Floating point operand expected.");
1847
1848  SDValue True  = DAG.getConstant(1, MVT::i32);
1849  SDValue False = DAG.getConstant(0, MVT::i32);
1850
1851  return CreateCMovFP(DAG, Cond, True, False, Op.getDebugLoc());
1852}
1853
1854SDValue MipsTargetLowering::LowerGlobalAddress(SDValue Op,
1855                                               SelectionDAG &DAG) const {
1856  // FIXME there isn't actually debug info here
1857  DebugLoc dl = Op.getDebugLoc();
1858  const GlobalValue *GV = cast<GlobalAddressSDNode>(Op)->getGlobal();
1859
1860  if (getTargetMachine().getRelocationModel() != Reloc::PIC_ && !IsN64) {
1861    const MipsTargetObjectFile &TLOF =
1862      (const MipsTargetObjectFile&)getObjFileLowering();
1863
1864    // %gp_rel relocation
1865    if (TLOF.IsGlobalInSmallSection(GV, getTargetMachine())) {
1866      SDValue GA = DAG.getTargetGlobalAddress(GV, dl, MVT::i32, 0,
1867                                              MipsII::MO_GPREL);
1868      SDValue GPRelNode = DAG.getNode(MipsISD::GPRel, dl,
1869                                      DAG.getVTList(MVT::i32), &GA, 1);
1870      SDValue GPReg = DAG.getRegister(Mips::GP, MVT::i32);
1871      return DAG.getNode(ISD::ADD, dl, MVT::i32, GPReg, GPRelNode);
1872    }
1873
1874    // %hi/%lo relocation
1875    return getAddrNonPIC(Op, DAG);
1876  }
1877
1878  if (GV->hasInternalLinkage() || (GV->hasLocalLinkage() && !isa<Function>(GV)))
1879    return getAddrLocal(Op, DAG, HasMips64);
1880
1881  if (LargeGOT)
1882    return getAddrGlobalLargeGOT(Op, DAG, MipsII::MO_GOT_HI16,
1883                                 MipsII::MO_GOT_LO16);
1884
1885  return getAddrGlobal(Op, DAG,
1886                       HasMips64 ? MipsII::MO_GOT_DISP : MipsII::MO_GOT16);
1887}
1888
1889SDValue MipsTargetLowering::LowerBlockAddress(SDValue Op,
1890                                              SelectionDAG &DAG) const {
1891  if (getTargetMachine().getRelocationModel() != Reloc::PIC_ && !IsN64)
1892    return getAddrNonPIC(Op, DAG);
1893
1894  return getAddrLocal(Op, DAG, HasMips64);
1895}
1896
1897SDValue MipsTargetLowering::
1898LowerGlobalTLSAddress(SDValue Op, SelectionDAG &DAG) const
1899{
1900  // If the relocation model is PIC, use the General Dynamic TLS Model or
1901  // Local Dynamic TLS model, otherwise use the Initial Exec or
1902  // Local Exec TLS Model.
1903
1904  GlobalAddressSDNode *GA = cast<GlobalAddressSDNode>(Op);
1905  DebugLoc dl = GA->getDebugLoc();
1906  const GlobalValue *GV = GA->getGlobal();
1907  EVT PtrVT = getPointerTy();
1908
1909  TLSModel::Model model = getTargetMachine().getTLSModel(GV);
1910
1911  if (model == TLSModel::GeneralDynamic || model == TLSModel::LocalDynamic) {
1912    // General Dynamic and Local Dynamic TLS Model.
1913    unsigned Flag = (model == TLSModel::LocalDynamic) ? MipsII::MO_TLSLDM
1914                                                      : MipsII::MO_TLSGD;
1915
1916    SDValue TGA = DAG.getTargetGlobalAddress(GV, dl, PtrVT, 0, Flag);
1917    SDValue Argument = DAG.getNode(MipsISD::Wrapper, dl, PtrVT,
1918                                   GetGlobalReg(DAG, PtrVT), TGA);
1919    unsigned PtrSize = PtrVT.getSizeInBits();
1920    IntegerType *PtrTy = Type::getIntNTy(*DAG.getContext(), PtrSize);
1921
1922    SDValue TlsGetAddr = DAG.getExternalSymbol("__tls_get_addr", PtrVT);
1923
1924    ArgListTy Args;
1925    ArgListEntry Entry;
1926    Entry.Node = Argument;
1927    Entry.Ty = PtrTy;
1928    Args.push_back(Entry);
1929
1930    TargetLowering::CallLoweringInfo CLI(DAG.getEntryNode(), PtrTy,
1931                  false, false, false, false, 0, CallingConv::C,
1932                  /*isTailCall=*/false, /*doesNotRet=*/false,
1933                  /*isReturnValueUsed=*/true,
1934                  TlsGetAddr, Args, DAG, dl);
1935    std::pair<SDValue, SDValue> CallResult = LowerCallTo(CLI);
1936
1937    SDValue Ret = CallResult.first;
1938
1939    if (model != TLSModel::LocalDynamic)
1940      return Ret;
1941
1942    SDValue TGAHi = DAG.getTargetGlobalAddress(GV, dl, PtrVT, 0,
1943                                               MipsII::MO_DTPREL_HI);
1944    SDValue Hi = DAG.getNode(MipsISD::Hi, dl, PtrVT, TGAHi);
1945    SDValue TGALo = DAG.getTargetGlobalAddress(GV, dl, PtrVT, 0,
1946                                               MipsII::MO_DTPREL_LO);
1947    SDValue Lo = DAG.getNode(MipsISD::Lo, dl, PtrVT, TGALo);
1948    SDValue Add = DAG.getNode(ISD::ADD, dl, PtrVT, Hi, Ret);
1949    return DAG.getNode(ISD::ADD, dl, PtrVT, Add, Lo);
1950  }
1951
1952  SDValue Offset;
1953  if (model == TLSModel::InitialExec) {
1954    // Initial Exec TLS Model
1955    SDValue TGA = DAG.getTargetGlobalAddress(GV, dl, PtrVT, 0,
1956                                             MipsII::MO_GOTTPREL);
1957    TGA = DAG.getNode(MipsISD::Wrapper, dl, PtrVT, GetGlobalReg(DAG, PtrVT),
1958                      TGA);
1959    Offset = DAG.getLoad(PtrVT, dl,
1960                         DAG.getEntryNode(), TGA, MachinePointerInfo(),
1961                         false, false, false, 0);
1962  } else {
1963    // Local Exec TLS Model
1964    assert(model == TLSModel::LocalExec);
1965    SDValue TGAHi = DAG.getTargetGlobalAddress(GV, dl, PtrVT, 0,
1966                                               MipsII::MO_TPREL_HI);
1967    SDValue TGALo = DAG.getTargetGlobalAddress(GV, dl, PtrVT, 0,
1968                                               MipsII::MO_TPREL_LO);
1969    SDValue Hi = DAG.getNode(MipsISD::Hi, dl, PtrVT, TGAHi);
1970    SDValue Lo = DAG.getNode(MipsISD::Lo, dl, PtrVT, TGALo);
1971    Offset = DAG.getNode(ISD::ADD, dl, PtrVT, Hi, Lo);
1972  }
1973
1974  SDValue ThreadPointer = DAG.getNode(MipsISD::ThreadPointer, dl, PtrVT);
1975  return DAG.getNode(ISD::ADD, dl, PtrVT, ThreadPointer, Offset);
1976}
1977
1978SDValue MipsTargetLowering::
1979LowerJumpTable(SDValue Op, SelectionDAG &DAG) const
1980{
1981  if (getTargetMachine().getRelocationModel() != Reloc::PIC_ && !IsN64)
1982    return getAddrNonPIC(Op, DAG);
1983
1984  return getAddrLocal(Op, DAG, HasMips64);
1985}
1986
1987SDValue MipsTargetLowering::
1988LowerConstantPool(SDValue Op, SelectionDAG &DAG) const
1989{
1990  // gp_rel relocation
1991  // FIXME: we should reference the constant pool using small data sections,
1992  // but the asm printer currently doesn't support this feature without
1993  // hacking it. This feature should come soon so we can uncomment the
1994  // stuff below.
1995  //if (IsInSmallSection(C->getType())) {
1996  //  SDValue GPRelNode = DAG.getNode(MipsISD::GPRel, MVT::i32, CP);
1997  //  SDValue GOT = DAG.getGLOBAL_OFFSET_TABLE(MVT::i32);
1998  //  ResNode = DAG.getNode(ISD::ADD, MVT::i32, GOT, GPRelNode);
1999
2000  if (getTargetMachine().getRelocationModel() != Reloc::PIC_ && !IsN64)
2001    return getAddrNonPIC(Op, DAG);
2002
2003  return getAddrLocal(Op, DAG, HasMips64);
2004}
2005
2006SDValue MipsTargetLowering::LowerVASTART(SDValue Op, SelectionDAG &DAG) const {
2007  MachineFunction &MF = DAG.getMachineFunction();
2008  MipsFunctionInfo *FuncInfo = MF.getInfo<MipsFunctionInfo>();
2009
2010  DebugLoc dl = Op.getDebugLoc();
2011  SDValue FI = DAG.getFrameIndex(FuncInfo->getVarArgsFrameIndex(),
2012                                 getPointerTy());
2013
2014  // vastart just stores the address of the VarArgsFrameIndex slot into the
2015  // memory location argument.
2016  const Value *SV = cast<SrcValueSDNode>(Op.getOperand(2))->getValue();
2017  return DAG.getStore(Op.getOperand(0), dl, FI, Op.getOperand(1),
2018                      MachinePointerInfo(SV), false, false, 0);
2019}
2020
2021static SDValue LowerFCOPYSIGN32(SDValue Op, SelectionDAG &DAG, bool HasR2) {
2022  EVT TyX = Op.getOperand(0).getValueType();
2023  EVT TyY = Op.getOperand(1).getValueType();
2024  SDValue Const1 = DAG.getConstant(1, MVT::i32);
2025  SDValue Const31 = DAG.getConstant(31, MVT::i32);
2026  DebugLoc DL = Op.getDebugLoc();
2027  SDValue Res;
2028
2029  // If operand is of type f64, extract the upper 32-bit. Otherwise, bitcast it
2030  // to i32.
2031  SDValue X = (TyX == MVT::f32) ?
2032    DAG.getNode(ISD::BITCAST, DL, MVT::i32, Op.getOperand(0)) :
2033    DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32, Op.getOperand(0),
2034                Const1);
2035  SDValue Y = (TyY == MVT::f32) ?
2036    DAG.getNode(ISD::BITCAST, DL, MVT::i32, Op.getOperand(1)) :
2037    DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32, Op.getOperand(1),
2038                Const1);
2039
2040  if (HasR2) {
2041    // ext  E, Y, 31, 1  ; extract bit31 of Y
2042    // ins  X, E, 31, 1  ; insert extracted bit at bit31 of X
2043    SDValue E = DAG.getNode(MipsISD::Ext, DL, MVT::i32, Y, Const31, Const1);
2044    Res = DAG.getNode(MipsISD::Ins, DL, MVT::i32, E, Const31, Const1, X);
2045  } else {
2046    // sll SllX, X, 1
2047    // srl SrlX, SllX, 1
2048    // srl SrlY, Y, 31
2049    // sll SllY, SrlX, 31
2050    // or  Or, SrlX, SllY
2051    SDValue SllX = DAG.getNode(ISD::SHL, DL, MVT::i32, X, Const1);
2052    SDValue SrlX = DAG.getNode(ISD::SRL, DL, MVT::i32, SllX, Const1);
2053    SDValue SrlY = DAG.getNode(ISD::SRL, DL, MVT::i32, Y, Const31);
2054    SDValue SllY = DAG.getNode(ISD::SHL, DL, MVT::i32, SrlY, Const31);
2055    Res = DAG.getNode(ISD::OR, DL, MVT::i32, SrlX, SllY);
2056  }
2057
2058  if (TyX == MVT::f32)
2059    return DAG.getNode(ISD::BITCAST, DL, Op.getOperand(0).getValueType(), Res);
2060
2061  SDValue LowX = DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32,
2062                             Op.getOperand(0), DAG.getConstant(0, MVT::i32));
2063  return DAG.getNode(MipsISD::BuildPairF64, DL, MVT::f64, LowX, Res);
2064}
2065
2066static SDValue LowerFCOPYSIGN64(SDValue Op, SelectionDAG &DAG, bool HasR2) {
2067  unsigned WidthX = Op.getOperand(0).getValueSizeInBits();
2068  unsigned WidthY = Op.getOperand(1).getValueSizeInBits();
2069  EVT TyX = MVT::getIntegerVT(WidthX), TyY = MVT::getIntegerVT(WidthY);
2070  SDValue Const1 = DAG.getConstant(1, MVT::i32);
2071  DebugLoc DL = Op.getDebugLoc();
2072
2073  // Bitcast to integer nodes.
2074  SDValue X = DAG.getNode(ISD::BITCAST, DL, TyX, Op.getOperand(0));
2075  SDValue Y = DAG.getNode(ISD::BITCAST, DL, TyY, Op.getOperand(1));
2076
2077  if (HasR2) {
2078    // ext  E, Y, width(Y) - 1, 1  ; extract bit width(Y)-1 of Y
2079    // ins  X, E, width(X) - 1, 1  ; insert extracted bit at bit width(X)-1 of X
2080    SDValue E = DAG.getNode(MipsISD::Ext, DL, TyY, Y,
2081                            DAG.getConstant(WidthY - 1, MVT::i32), Const1);
2082
2083    if (WidthX > WidthY)
2084      E = DAG.getNode(ISD::ZERO_EXTEND, DL, TyX, E);
2085    else if (WidthY > WidthX)
2086      E = DAG.getNode(ISD::TRUNCATE, DL, TyX, E);
2087
2088    SDValue I = DAG.getNode(MipsISD::Ins, DL, TyX, E,
2089                            DAG.getConstant(WidthX - 1, MVT::i32), Const1, X);
2090    return DAG.getNode(ISD::BITCAST, DL, Op.getOperand(0).getValueType(), I);
2091  }
2092
2093  // (d)sll SllX, X, 1
2094  // (d)srl SrlX, SllX, 1
2095  // (d)srl SrlY, Y, width(Y)-1
2096  // (d)sll SllY, SrlX, width(Y)-1
2097  // or     Or, SrlX, SllY
2098  SDValue SllX = DAG.getNode(ISD::SHL, DL, TyX, X, Const1);
2099  SDValue SrlX = DAG.getNode(ISD::SRL, DL, TyX, SllX, Const1);
2100  SDValue SrlY = DAG.getNode(ISD::SRL, DL, TyY, Y,
2101                             DAG.getConstant(WidthY - 1, MVT::i32));
2102
2103  if (WidthX > WidthY)
2104    SrlY = DAG.getNode(ISD::ZERO_EXTEND, DL, TyX, SrlY);
2105  else if (WidthY > WidthX)
2106    SrlY = DAG.getNode(ISD::TRUNCATE, DL, TyX, SrlY);
2107
2108  SDValue SllY = DAG.getNode(ISD::SHL, DL, TyX, SrlY,
2109                             DAG.getConstant(WidthX - 1, MVT::i32));
2110  SDValue Or = DAG.getNode(ISD::OR, DL, TyX, SrlX, SllY);
2111  return DAG.getNode(ISD::BITCAST, DL, Op.getOperand(0).getValueType(), Or);
2112}
2113
2114SDValue
2115MipsTargetLowering::LowerFCOPYSIGN(SDValue Op, SelectionDAG &DAG) const {
2116  if (Subtarget->hasMips64())
2117    return LowerFCOPYSIGN64(Op, DAG, Subtarget->hasMips32r2());
2118
2119  return LowerFCOPYSIGN32(Op, DAG, Subtarget->hasMips32r2());
2120}
2121
2122static SDValue LowerFABS32(SDValue Op, SelectionDAG &DAG, bool HasR2) {
2123  SDValue Res, Const1 = DAG.getConstant(1, MVT::i32);
2124  DebugLoc DL = Op.getDebugLoc();
2125
2126  // If operand is of type f64, extract the upper 32-bit. Otherwise, bitcast it
2127  // to i32.
2128  SDValue X = (Op.getValueType() == MVT::f32) ?
2129    DAG.getNode(ISD::BITCAST, DL, MVT::i32, Op.getOperand(0)) :
2130    DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32, Op.getOperand(0),
2131                Const1);
2132
2133  // Clear MSB.
2134  if (HasR2)
2135    Res = DAG.getNode(MipsISD::Ins, DL, MVT::i32,
2136                      DAG.getRegister(Mips::ZERO, MVT::i32),
2137                      DAG.getConstant(31, MVT::i32), Const1, X);
2138  else {
2139    SDValue SllX = DAG.getNode(ISD::SHL, DL, MVT::i32, X, Const1);
2140    Res = DAG.getNode(ISD::SRL, DL, MVT::i32, SllX, Const1);
2141  }
2142
2143  if (Op.getValueType() == MVT::f32)
2144    return DAG.getNode(ISD::BITCAST, DL, MVT::f32, Res);
2145
2146  SDValue LowX = DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32,
2147                             Op.getOperand(0), DAG.getConstant(0, MVT::i32));
2148  return DAG.getNode(MipsISD::BuildPairF64, DL, MVT::f64, LowX, Res);
2149}
2150
2151static SDValue LowerFABS64(SDValue Op, SelectionDAG &DAG, bool HasR2) {
2152  SDValue Res, Const1 = DAG.getConstant(1, MVT::i32);
2153  DebugLoc DL = Op.getDebugLoc();
2154
2155  // Bitcast to integer node.
2156  SDValue X = DAG.getNode(ISD::BITCAST, DL, MVT::i64, Op.getOperand(0));
2157
2158  // Clear MSB.
2159  if (HasR2)
2160    Res = DAG.getNode(MipsISD::Ins, DL, MVT::i64,
2161                      DAG.getRegister(Mips::ZERO_64, MVT::i64),
2162                      DAG.getConstant(63, MVT::i32), Const1, X);
2163  else {
2164    SDValue SllX = DAG.getNode(ISD::SHL, DL, MVT::i64, X, Const1);
2165    Res = DAG.getNode(ISD::SRL, DL, MVT::i64, SllX, Const1);
2166  }
2167
2168  return DAG.getNode(ISD::BITCAST, DL, MVT::f64, Res);
2169}
2170
2171SDValue
2172MipsTargetLowering::LowerFABS(SDValue Op, SelectionDAG &DAG) const {
2173  if (Subtarget->hasMips64() && (Op.getValueType() == MVT::f64))
2174    return LowerFABS64(Op, DAG, Subtarget->hasMips32r2());
2175
2176  return LowerFABS32(Op, DAG, Subtarget->hasMips32r2());
2177}
2178
2179SDValue MipsTargetLowering::
2180LowerFRAMEADDR(SDValue Op, SelectionDAG &DAG) const {
2181  // check the depth
2182  assert((cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue() == 0) &&
2183         "Frame address can only be determined for current frame.");
2184
2185  MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo();
2186  MFI->setFrameAddressIsTaken(true);
2187  EVT VT = Op.getValueType();
2188  DebugLoc dl = Op.getDebugLoc();
2189  SDValue FrameAddr = DAG.getCopyFromReg(DAG.getEntryNode(), dl,
2190                                         IsN64 ? Mips::FP_64 : Mips::FP, VT);
2191  return FrameAddr;
2192}
2193
2194SDValue MipsTargetLowering::LowerRETURNADDR(SDValue Op,
2195                                            SelectionDAG &DAG) const {
2196  // check the depth
2197  assert((cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue() == 0) &&
2198         "Return address can be determined only for current frame.");
2199
2200  MachineFunction &MF = DAG.getMachineFunction();
2201  MachineFrameInfo *MFI = MF.getFrameInfo();
2202  MVT VT = Op.getSimpleValueType();
2203  unsigned RA = IsN64 ? Mips::RA_64 : Mips::RA;
2204  MFI->setReturnAddressIsTaken(true);
2205
2206  // Return RA, which contains the return address. Mark it an implicit live-in.
2207  unsigned Reg = MF.addLiveIn(RA, getRegClassFor(VT));
2208  return DAG.getCopyFromReg(DAG.getEntryNode(), Op.getDebugLoc(), Reg, VT);
2209}
2210
2211// TODO: set SType according to the desired memory barrier behavior.
2212SDValue
2213MipsTargetLowering::LowerMEMBARRIER(SDValue Op, SelectionDAG &DAG) const {
2214  unsigned SType = 0;
2215  DebugLoc dl = Op.getDebugLoc();
2216  return DAG.getNode(MipsISD::Sync, dl, MVT::Other, Op.getOperand(0),
2217                     DAG.getConstant(SType, MVT::i32));
2218}
2219
2220SDValue MipsTargetLowering::LowerATOMIC_FENCE(SDValue Op,
2221                                              SelectionDAG &DAG) const {
2222  // FIXME: Need pseudo-fence for 'singlethread' fences
2223  // FIXME: Set SType for weaker fences where supported/appropriate.
2224  unsigned SType = 0;
2225  DebugLoc dl = Op.getDebugLoc();
2226  return DAG.getNode(MipsISD::Sync, dl, MVT::Other, Op.getOperand(0),
2227                     DAG.getConstant(SType, MVT::i32));
2228}
2229
2230SDValue MipsTargetLowering::LowerShiftLeftParts(SDValue Op,
2231                                                SelectionDAG &DAG) const {
2232  DebugLoc DL = Op.getDebugLoc();
2233  SDValue Lo = Op.getOperand(0), Hi = Op.getOperand(1);
2234  SDValue Shamt = Op.getOperand(2);
2235
2236  // if shamt < 32:
2237  //  lo = (shl lo, shamt)
2238  //  hi = (or (shl hi, shamt) (srl (srl lo, 1), ~shamt))
2239  // else:
2240  //  lo = 0
2241  //  hi = (shl lo, shamt[4:0])
2242  SDValue Not = DAG.getNode(ISD::XOR, DL, MVT::i32, Shamt,
2243                            DAG.getConstant(-1, MVT::i32));
2244  SDValue ShiftRight1Lo = DAG.getNode(ISD::SRL, DL, MVT::i32, Lo,
2245                                      DAG.getConstant(1, MVT::i32));
2246  SDValue ShiftRightLo = DAG.getNode(ISD::SRL, DL, MVT::i32, ShiftRight1Lo,
2247                                     Not);
2248  SDValue ShiftLeftHi = DAG.getNode(ISD::SHL, DL, MVT::i32, Hi, Shamt);
2249  SDValue Or = DAG.getNode(ISD::OR, DL, MVT::i32, ShiftLeftHi, ShiftRightLo);
2250  SDValue ShiftLeftLo = DAG.getNode(ISD::SHL, DL, MVT::i32, Lo, Shamt);
2251  SDValue Cond = DAG.getNode(ISD::AND, DL, MVT::i32, Shamt,
2252                             DAG.getConstant(0x20, MVT::i32));
2253  Lo = DAG.getNode(ISD::SELECT, DL, MVT::i32, Cond,
2254                   DAG.getConstant(0, MVT::i32), ShiftLeftLo);
2255  Hi = DAG.getNode(ISD::SELECT, DL, MVT::i32, Cond, ShiftLeftLo, Or);
2256
2257  SDValue Ops[2] = {Lo, Hi};
2258  return DAG.getMergeValues(Ops, 2, DL);
2259}
2260
2261SDValue MipsTargetLowering::LowerShiftRightParts(SDValue Op, SelectionDAG &DAG,
2262                                                 bool IsSRA) const {
2263  DebugLoc DL = Op.getDebugLoc();
2264  SDValue Lo = Op.getOperand(0), Hi = Op.getOperand(1);
2265  SDValue Shamt = Op.getOperand(2);
2266
2267  // if shamt < 32:
2268  //  lo = (or (shl (shl hi, 1), ~shamt) (srl lo, shamt))
2269  //  if isSRA:
2270  //    hi = (sra hi, shamt)
2271  //  else:
2272  //    hi = (srl hi, shamt)
2273  // else:
2274  //  if isSRA:
2275  //   lo = (sra hi, shamt[4:0])
2276  //   hi = (sra hi, 31)
2277  //  else:
2278  //   lo = (srl hi, shamt[4:0])
2279  //   hi = 0
2280  SDValue Not = DAG.getNode(ISD::XOR, DL, MVT::i32, Shamt,
2281                            DAG.getConstant(-1, MVT::i32));
2282  SDValue ShiftLeft1Hi = DAG.getNode(ISD::SHL, DL, MVT::i32, Hi,
2283                                     DAG.getConstant(1, MVT::i32));
2284  SDValue ShiftLeftHi = DAG.getNode(ISD::SHL, DL, MVT::i32, ShiftLeft1Hi, Not);
2285  SDValue ShiftRightLo = DAG.getNode(ISD::SRL, DL, MVT::i32, Lo, Shamt);
2286  SDValue Or = DAG.getNode(ISD::OR, DL, MVT::i32, ShiftLeftHi, ShiftRightLo);
2287  SDValue ShiftRightHi = DAG.getNode(IsSRA ? ISD::SRA : ISD::SRL, DL, MVT::i32,
2288                                     Hi, Shamt);
2289  SDValue Cond = DAG.getNode(ISD::AND, DL, MVT::i32, Shamt,
2290                             DAG.getConstant(0x20, MVT::i32));
2291  SDValue Shift31 = DAG.getNode(ISD::SRA, DL, MVT::i32, Hi,
2292                                DAG.getConstant(31, MVT::i32));
2293  Lo = DAG.getNode(ISD::SELECT, DL, MVT::i32, Cond, ShiftRightHi, Or);
2294  Hi = DAG.getNode(ISD::SELECT, DL, MVT::i32, Cond,
2295                   IsSRA ? Shift31 : DAG.getConstant(0, MVT::i32),
2296                   ShiftRightHi);
2297
2298  SDValue Ops[2] = {Lo, Hi};
2299  return DAG.getMergeValues(Ops, 2, DL);
2300}
2301
2302static SDValue CreateLoadLR(unsigned Opc, SelectionDAG &DAG, LoadSDNode *LD,
2303                            SDValue Chain, SDValue Src, unsigned Offset) {
2304  SDValue Ptr = LD->getBasePtr();
2305  EVT VT = LD->getValueType(0), MemVT = LD->getMemoryVT();
2306  EVT BasePtrVT = Ptr.getValueType();
2307  DebugLoc DL = LD->getDebugLoc();
2308  SDVTList VTList = DAG.getVTList(VT, MVT::Other);
2309
2310  if (Offset)
2311    Ptr = DAG.getNode(ISD::ADD, DL, BasePtrVT, Ptr,
2312                      DAG.getConstant(Offset, BasePtrVT));
2313
2314  SDValue Ops[] = { Chain, Ptr, Src };
2315  return DAG.getMemIntrinsicNode(Opc, DL, VTList, Ops, 3, MemVT,
2316                                 LD->getMemOperand());
2317}
2318
2319// Expand an unaligned 32 or 64-bit integer load node.
2320SDValue MipsTargetLowering::LowerLOAD(SDValue Op, SelectionDAG &DAG) const {
2321  LoadSDNode *LD = cast<LoadSDNode>(Op);
2322  EVT MemVT = LD->getMemoryVT();
2323
2324  // Return if load is aligned or if MemVT is neither i32 nor i64.
2325  if ((LD->getAlignment() >= MemVT.getSizeInBits() / 8) ||
2326      ((MemVT != MVT::i32) && (MemVT != MVT::i64)))
2327    return SDValue();
2328
2329  bool IsLittle = Subtarget->isLittle();
2330  EVT VT = Op.getValueType();
2331  ISD::LoadExtType ExtType = LD->getExtensionType();
2332  SDValue Chain = LD->getChain(), Undef = DAG.getUNDEF(VT);
2333
2334  assert((VT == MVT::i32) || (VT == MVT::i64));
2335
2336  // Expand
2337  //  (set dst, (i64 (load baseptr)))
2338  // to
2339  //  (set tmp, (ldl (add baseptr, 7), undef))
2340  //  (set dst, (ldr baseptr, tmp))
2341  if ((VT == MVT::i64) && (ExtType == ISD::NON_EXTLOAD)) {
2342    SDValue LDL = CreateLoadLR(MipsISD::LDL, DAG, LD, Chain, Undef,
2343                               IsLittle ? 7 : 0);
2344    return CreateLoadLR(MipsISD::LDR, DAG, LD, LDL.getValue(1), LDL,
2345                        IsLittle ? 0 : 7);
2346  }
2347
2348  SDValue LWL = CreateLoadLR(MipsISD::LWL, DAG, LD, Chain, Undef,
2349                             IsLittle ? 3 : 0);
2350  SDValue LWR = CreateLoadLR(MipsISD::LWR, DAG, LD, LWL.getValue(1), LWL,
2351                             IsLittle ? 0 : 3);
2352
2353  // Expand
2354  //  (set dst, (i32 (load baseptr))) or
2355  //  (set dst, (i64 (sextload baseptr))) or
2356  //  (set dst, (i64 (extload baseptr)))
2357  // to
2358  //  (set tmp, (lwl (add baseptr, 3), undef))
2359  //  (set dst, (lwr baseptr, tmp))
2360  if ((VT == MVT::i32) || (ExtType == ISD::SEXTLOAD) ||
2361      (ExtType == ISD::EXTLOAD))
2362    return LWR;
2363
2364  assert((VT == MVT::i64) && (ExtType == ISD::ZEXTLOAD));
2365
2366  // Expand
2367  //  (set dst, (i64 (zextload baseptr)))
2368  // to
2369  //  (set tmp0, (lwl (add baseptr, 3), undef))
2370  //  (set tmp1, (lwr baseptr, tmp0))
2371  //  (set tmp2, (shl tmp1, 32))
2372  //  (set dst, (srl tmp2, 32))
2373  DebugLoc DL = LD->getDebugLoc();
2374  SDValue Const32 = DAG.getConstant(32, MVT::i32);
2375  SDValue SLL = DAG.getNode(ISD::SHL, DL, MVT::i64, LWR, Const32);
2376  SDValue SRL = DAG.getNode(ISD::SRL, DL, MVT::i64, SLL, Const32);
2377  SDValue Ops[] = { SRL, LWR.getValue(1) };
2378  return DAG.getMergeValues(Ops, 2, DL);
2379}
2380
2381static SDValue CreateStoreLR(unsigned Opc, SelectionDAG &DAG, StoreSDNode *SD,
2382                             SDValue Chain, unsigned Offset) {
2383  SDValue Ptr = SD->getBasePtr(), Value = SD->getValue();
2384  EVT MemVT = SD->getMemoryVT(), BasePtrVT = Ptr.getValueType();
2385  DebugLoc DL = SD->getDebugLoc();
2386  SDVTList VTList = DAG.getVTList(MVT::Other);
2387
2388  if (Offset)
2389    Ptr = DAG.getNode(ISD::ADD, DL, BasePtrVT, Ptr,
2390                      DAG.getConstant(Offset, BasePtrVT));
2391
2392  SDValue Ops[] = { Chain, Value, Ptr };
2393  return DAG.getMemIntrinsicNode(Opc, DL, VTList, Ops, 3, MemVT,
2394                                 SD->getMemOperand());
2395}
2396
2397// Expand an unaligned 32 or 64-bit integer store node.
2398SDValue MipsTargetLowering::LowerSTORE(SDValue Op, SelectionDAG &DAG) const {
2399  StoreSDNode *SD = cast<StoreSDNode>(Op);
2400  EVT MemVT = SD->getMemoryVT();
2401
2402  // Return if store is aligned or if MemVT is neither i32 nor i64.
2403  if ((SD->getAlignment() >= MemVT.getSizeInBits() / 8) ||
2404      ((MemVT != MVT::i32) && (MemVT != MVT::i64)))
2405    return SDValue();
2406
2407  bool IsLittle = Subtarget->isLittle();
2408  SDValue Value = SD->getValue(), Chain = SD->getChain();
2409  EVT VT = Value.getValueType();
2410
2411  // Expand
2412  //  (store val, baseptr) or
2413  //  (truncstore val, baseptr)
2414  // to
2415  //  (swl val, (add baseptr, 3))
2416  //  (swr val, baseptr)
2417  if ((VT == MVT::i32) || SD->isTruncatingStore()) {
2418    SDValue SWL = CreateStoreLR(MipsISD::SWL, DAG, SD, Chain,
2419                                IsLittle ? 3 : 0);
2420    return CreateStoreLR(MipsISD::SWR, DAG, SD, SWL, IsLittle ? 0 : 3);
2421  }
2422
2423  assert(VT == MVT::i64);
2424
2425  // Expand
2426  //  (store val, baseptr)
2427  // to
2428  //  (sdl val, (add baseptr, 7))
2429  //  (sdr val, baseptr)
2430  SDValue SDL = CreateStoreLR(MipsISD::SDL, DAG, SD, Chain, IsLittle ? 7 : 0);
2431  return CreateStoreLR(MipsISD::SDR, DAG, SD, SDL, IsLittle ? 0 : 7);
2432}
2433
2434// This function expands mips intrinsic nodes which have 64-bit input operands
2435// or output values.
2436//
2437// out64 = intrinsic-node in64
2438// =>
2439// lo = copy (extract-element (in64, 0))
2440// hi = copy (extract-element (in64, 1))
2441// mips-specific-node
2442// v0 = copy lo
2443// v1 = copy hi
2444// out64 = merge-values (v0, v1)
2445//
2446static SDValue LowerDSPIntr(SDValue Op, SelectionDAG &DAG,
2447                            unsigned Opc, bool HasI64In, bool HasI64Out) {
2448  DebugLoc DL = Op.getDebugLoc();
2449  bool HasChainIn = Op->getOperand(0).getValueType() == MVT::Other;
2450  SDValue Chain = HasChainIn ? Op->getOperand(0) : DAG.getEntryNode();
2451  SmallVector<SDValue, 3> Ops;
2452
2453  if (HasI64In) {
2454    SDValue InLo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, MVT::i32,
2455                               Op->getOperand(1 + HasChainIn),
2456                               DAG.getConstant(0, MVT::i32));
2457    SDValue InHi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, MVT::i32,
2458                               Op->getOperand(1 + HasChainIn),
2459                               DAG.getConstant(1, MVT::i32));
2460
2461    Chain = DAG.getCopyToReg(Chain, DL, Mips::LO, InLo, SDValue());
2462    Chain = DAG.getCopyToReg(Chain, DL, Mips::HI, InHi, Chain.getValue(1));
2463
2464    Ops.push_back(Chain);
2465    Ops.append(Op->op_begin() + HasChainIn + 2, Op->op_end());
2466    Ops.push_back(Chain.getValue(1));
2467  } else {
2468    Ops.push_back(Chain);
2469    Ops.append(Op->op_begin() + HasChainIn + 1, Op->op_end());
2470  }
2471
2472  if (!HasI64Out)
2473    return DAG.getNode(Opc, DL, Op->value_begin(), Op->getNumValues(),
2474                       Ops.begin(), Ops.size());
2475
2476  SDValue Intr = DAG.getNode(Opc, DL, DAG.getVTList(MVT::Other, MVT::Glue),
2477                             Ops.begin(), Ops.size());
2478  SDValue OutLo = DAG.getCopyFromReg(Intr.getValue(0), DL, Mips::LO, MVT::i32,
2479                                     Intr.getValue(1));
2480  SDValue OutHi = DAG.getCopyFromReg(OutLo.getValue(1), DL, Mips::HI, MVT::i32,
2481                                     OutLo.getValue(2));
2482  SDValue Out = DAG.getNode(ISD::BUILD_PAIR, DL, MVT::i64, OutLo, OutHi);
2483
2484  if (!HasChainIn)
2485    return Out;
2486
2487  SDValue Vals[] = { Out, OutHi.getValue(1) };
2488  return DAG.getMergeValues(Vals, 2, DL);
2489}
2490
2491SDValue MipsTargetLowering::LowerINTRINSIC_WO_CHAIN(SDValue Op,
2492                                                    SelectionDAG &DAG) const {
2493  switch (cast<ConstantSDNode>(Op->getOperand(0))->getZExtValue()) {
2494  default:
2495    return SDValue();
2496  case Intrinsic::mips_shilo:
2497    return LowerDSPIntr(Op, DAG, MipsISD::SHILO, true, true);
2498  case Intrinsic::mips_dpau_h_qbl:
2499    return LowerDSPIntr(Op, DAG, MipsISD::DPAU_H_QBL, true, true);
2500  case Intrinsic::mips_dpau_h_qbr:
2501    return LowerDSPIntr(Op, DAG, MipsISD::DPAU_H_QBR, true, true);
2502  case Intrinsic::mips_dpsu_h_qbl:
2503    return LowerDSPIntr(Op, DAG, MipsISD::DPSU_H_QBL, true, true);
2504  case Intrinsic::mips_dpsu_h_qbr:
2505    return LowerDSPIntr(Op, DAG, MipsISD::DPSU_H_QBR, true, true);
2506  case Intrinsic::mips_dpa_w_ph:
2507    return LowerDSPIntr(Op, DAG, MipsISD::DPA_W_PH, true, true);
2508  case Intrinsic::mips_dps_w_ph:
2509    return LowerDSPIntr(Op, DAG, MipsISD::DPS_W_PH, true, true);
2510  case Intrinsic::mips_dpax_w_ph:
2511    return LowerDSPIntr(Op, DAG, MipsISD::DPAX_W_PH, true, true);
2512  case Intrinsic::mips_dpsx_w_ph:
2513    return LowerDSPIntr(Op, DAG, MipsISD::DPSX_W_PH, true, true);
2514  case Intrinsic::mips_mulsa_w_ph:
2515    return LowerDSPIntr(Op, DAG, MipsISD::MULSA_W_PH, true, true);
2516  case Intrinsic::mips_mult:
2517    return LowerDSPIntr(Op, DAG, MipsISD::MULT, false, true);
2518  case Intrinsic::mips_multu:
2519    return LowerDSPIntr(Op, DAG, MipsISD::MULTU, false, true);
2520  case Intrinsic::mips_madd:
2521    return LowerDSPIntr(Op, DAG, MipsISD::MADD_DSP, true, true);
2522  case Intrinsic::mips_maddu:
2523    return LowerDSPIntr(Op, DAG, MipsISD::MADDU_DSP, true, true);
2524  case Intrinsic::mips_msub:
2525    return LowerDSPIntr(Op, DAG, MipsISD::MSUB_DSP, true, true);
2526  case Intrinsic::mips_msubu:
2527    return LowerDSPIntr(Op, DAG, MipsISD::MSUBU_DSP, true, true);
2528  }
2529}
2530
2531SDValue MipsTargetLowering::LowerINTRINSIC_W_CHAIN(SDValue Op,
2532                                                   SelectionDAG &DAG) const {
2533  switch (cast<ConstantSDNode>(Op->getOperand(1))->getZExtValue()) {
2534  default:
2535    return SDValue();
2536  case Intrinsic::mips_extp:
2537    return LowerDSPIntr(Op, DAG, MipsISD::EXTP, true, false);
2538  case Intrinsic::mips_extpdp:
2539    return LowerDSPIntr(Op, DAG, MipsISD::EXTPDP, true, false);
2540  case Intrinsic::mips_extr_w:
2541    return LowerDSPIntr(Op, DAG, MipsISD::EXTR_W, true, false);
2542  case Intrinsic::mips_extr_r_w:
2543    return LowerDSPIntr(Op, DAG, MipsISD::EXTR_R_W, true, false);
2544  case Intrinsic::mips_extr_rs_w:
2545    return LowerDSPIntr(Op, DAG, MipsISD::EXTR_RS_W, true, false);
2546  case Intrinsic::mips_extr_s_h:
2547    return LowerDSPIntr(Op, DAG, MipsISD::EXTR_S_H, true, false);
2548  case Intrinsic::mips_mthlip:
2549    return LowerDSPIntr(Op, DAG, MipsISD::MTHLIP, true, true);
2550  case Intrinsic::mips_mulsaq_s_w_ph:
2551    return LowerDSPIntr(Op, DAG, MipsISD::MULSAQ_S_W_PH, true, true);
2552  case Intrinsic::mips_maq_s_w_phl:
2553    return LowerDSPIntr(Op, DAG, MipsISD::MAQ_S_W_PHL, true, true);
2554  case Intrinsic::mips_maq_s_w_phr:
2555    return LowerDSPIntr(Op, DAG, MipsISD::MAQ_S_W_PHR, true, true);
2556  case Intrinsic::mips_maq_sa_w_phl:
2557    return LowerDSPIntr(Op, DAG, MipsISD::MAQ_SA_W_PHL, true, true);
2558  case Intrinsic::mips_maq_sa_w_phr:
2559    return LowerDSPIntr(Op, DAG, MipsISD::MAQ_SA_W_PHR, true, true);
2560  case Intrinsic::mips_dpaq_s_w_ph:
2561    return LowerDSPIntr(Op, DAG, MipsISD::DPAQ_S_W_PH, true, true);
2562  case Intrinsic::mips_dpsq_s_w_ph:
2563    return LowerDSPIntr(Op, DAG, MipsISD::DPSQ_S_W_PH, true, true);
2564  case Intrinsic::mips_dpaq_sa_l_w:
2565    return LowerDSPIntr(Op, DAG, MipsISD::DPAQ_SA_L_W, true, true);
2566  case Intrinsic::mips_dpsq_sa_l_w:
2567    return LowerDSPIntr(Op, DAG, MipsISD::DPSQ_SA_L_W, true, true);
2568  case Intrinsic::mips_dpaqx_s_w_ph:
2569    return LowerDSPIntr(Op, DAG, MipsISD::DPAQX_S_W_PH, true, true);
2570  case Intrinsic::mips_dpaqx_sa_w_ph:
2571    return LowerDSPIntr(Op, DAG, MipsISD::DPAQX_SA_W_PH, true, true);
2572  case Intrinsic::mips_dpsqx_s_w_ph:
2573    return LowerDSPIntr(Op, DAG, MipsISD::DPSQX_S_W_PH, true, true);
2574  case Intrinsic::mips_dpsqx_sa_w_ph:
2575    return LowerDSPIntr(Op, DAG, MipsISD::DPSQX_SA_W_PH, true, true);
2576  }
2577}
2578
2579SDValue MipsTargetLowering::LowerADD(SDValue Op, SelectionDAG &DAG) const {
2580  if (Op->getOperand(0).getOpcode() != ISD::FRAMEADDR
2581      || cast<ConstantSDNode>
2582        (Op->getOperand(0).getOperand(0))->getZExtValue() != 0
2583      || Op->getOperand(1).getOpcode() != ISD::FRAME_TO_ARGS_OFFSET)
2584    return SDValue();
2585
2586  // The pattern
2587  //   (add (frameaddr 0), (frame_to_args_offset))
2588  // results from lowering llvm.eh.dwarf.cfa intrinsic. Transform it to
2589  //   (add FrameObject, 0)
2590  // where FrameObject is a fixed StackObject with offset 0 which points to
2591  // the old stack pointer.
2592  MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo();
2593  EVT ValTy = Op->getValueType(0);
2594  int FI = MFI->CreateFixedObject(Op.getValueSizeInBits() / 8, 0, false);
2595  SDValue InArgsAddr = DAG.getFrameIndex(FI, ValTy);
2596  return DAG.getNode(ISD::ADD, Op->getDebugLoc(), ValTy, InArgsAddr,
2597                     DAG.getConstant(0, ValTy));
2598}
2599
2600//===----------------------------------------------------------------------===//
2601//                      Calling Convention Implementation
2602//===----------------------------------------------------------------------===//
2603
2604//===----------------------------------------------------------------------===//
2605// TODO: Implement a generic logic using tblgen that can support this.
2606// Mips O32 ABI rules:
2607// ---
2608// i32 - Passed in A0, A1, A2, A3 and stack
2609// f32 - Only passed in f32 registers if no int reg has been used yet to hold
2610//       an argument. Otherwise, passed in A1, A2, A3 and stack.
2611// f64 - Only passed in two aliased f32 registers if no int reg has been used
2612//       yet to hold an argument. Otherwise, use A2, A3 and stack. If A1 is
2613//       not used, it must be shadowed. If only A3 is avaiable, shadow it and
2614//       go to stack.
2615//
2616//  For vararg functions, all arguments are passed in A0, A1, A2, A3 and stack.
2617//===----------------------------------------------------------------------===//
2618
2619static bool CC_MipsO32(unsigned ValNo, MVT ValVT,
2620                       MVT LocVT, CCValAssign::LocInfo LocInfo,
2621                       ISD::ArgFlagsTy ArgFlags, CCState &State) {
2622
2623  static const unsigned IntRegsSize=4, FloatRegsSize=2;
2624
2625  static const uint16_t IntRegs[] = {
2626      Mips::A0, Mips::A1, Mips::A2, Mips::A3
2627  };
2628  static const uint16_t F32Regs[] = {
2629      Mips::F12, Mips::F14
2630  };
2631  static const uint16_t F64Regs[] = {
2632      Mips::D6, Mips::D7
2633  };
2634
2635  // Do not process byval args here.
2636  if (ArgFlags.isByVal())
2637    return true;
2638
2639  // Promote i8 and i16
2640  if (LocVT == MVT::i8 || LocVT == MVT::i16) {
2641    LocVT = MVT::i32;
2642    if (ArgFlags.isSExt())
2643      LocInfo = CCValAssign::SExt;
2644    else if (ArgFlags.isZExt())
2645      LocInfo = CCValAssign::ZExt;
2646    else
2647      LocInfo = CCValAssign::AExt;
2648  }
2649
2650  unsigned Reg;
2651
2652  // f32 and f64 are allocated in A0, A1, A2, A3 when either of the following
2653  // is true: function is vararg, argument is 3rd or higher, there is previous
2654  // argument which is not f32 or f64.
2655  bool AllocateFloatsInIntReg = State.isVarArg() || ValNo > 1
2656      || State.getFirstUnallocated(F32Regs, FloatRegsSize) != ValNo;
2657  unsigned OrigAlign = ArgFlags.getOrigAlign();
2658  bool isI64 = (ValVT == MVT::i32 && OrigAlign == 8);
2659
2660  if (ValVT == MVT::i32 || (ValVT == MVT::f32 && AllocateFloatsInIntReg)) {
2661    Reg = State.AllocateReg(IntRegs, IntRegsSize);
2662    // If this is the first part of an i64 arg,
2663    // the allocated register must be either A0 or A2.
2664    if (isI64 && (Reg == Mips::A1 || Reg == Mips::A3))
2665      Reg = State.AllocateReg(IntRegs, IntRegsSize);
2666    LocVT = MVT::i32;
2667  } else if (ValVT == MVT::f64 && AllocateFloatsInIntReg) {
2668    // Allocate int register and shadow next int register. If first
2669    // available register is Mips::A1 or Mips::A3, shadow it too.
2670    Reg = State.AllocateReg(IntRegs, IntRegsSize);
2671    if (Reg == Mips::A1 || Reg == Mips::A3)
2672      Reg = State.AllocateReg(IntRegs, IntRegsSize);
2673    State.AllocateReg(IntRegs, IntRegsSize);
2674    LocVT = MVT::i32;
2675  } else if (ValVT.isFloatingPoint() && !AllocateFloatsInIntReg) {
2676    // we are guaranteed to find an available float register
2677    if (ValVT == MVT::f32) {
2678      Reg = State.AllocateReg(F32Regs, FloatRegsSize);
2679      // Shadow int register
2680      State.AllocateReg(IntRegs, IntRegsSize);
2681    } else {
2682      Reg = State.AllocateReg(F64Regs, FloatRegsSize);
2683      // Shadow int registers
2684      unsigned Reg2 = State.AllocateReg(IntRegs, IntRegsSize);
2685      if (Reg2 == Mips::A1 || Reg2 == Mips::A3)
2686        State.AllocateReg(IntRegs, IntRegsSize);
2687      State.AllocateReg(IntRegs, IntRegsSize);
2688    }
2689  } else
2690    llvm_unreachable("Cannot handle this ValVT.");
2691
2692  if (!Reg) {
2693    unsigned Offset = State.AllocateStack(ValVT.getSizeInBits() >> 3,
2694                                          OrigAlign);
2695    State.addLoc(CCValAssign::getMem(ValNo, ValVT, Offset, LocVT, LocInfo));
2696  } else
2697    State.addLoc(CCValAssign::getReg(ValNo, ValVT, Reg, LocVT, LocInfo));
2698
2699  return false;
2700}
2701
2702#include "MipsGenCallingConv.inc"
2703
2704//===----------------------------------------------------------------------===//
2705//                  Call Calling Convention Implementation
2706//===----------------------------------------------------------------------===//
2707
2708static const unsigned O32IntRegsSize = 4;
2709
2710// Return next O32 integer argument register.
2711static unsigned getNextIntArgReg(unsigned Reg) {
2712  assert((Reg == Mips::A0) || (Reg == Mips::A2));
2713  return (Reg == Mips::A0) ? Mips::A1 : Mips::A3;
2714}
2715
2716/// IsEligibleForTailCallOptimization - Check whether the call is eligible
2717/// for tail call optimization.
2718bool MipsTargetLowering::
2719IsEligibleForTailCallOptimization(const MipsCC &MipsCCInfo,
2720                                  unsigned NextStackOffset,
2721                                  const MipsFunctionInfo& FI) const {
2722  if (!EnableMipsTailCalls)
2723    return false;
2724
2725  // No tail call optimization for mips16.
2726  if (Subtarget->inMips16Mode())
2727    return false;
2728
2729  // Return false if either the callee or caller has a byval argument.
2730  if (MipsCCInfo.hasByValArg() || FI.hasByvalArg())
2731    return false;
2732
2733  // Return true if the callee's argument area is no larger than the
2734  // caller's.
2735  return NextStackOffset <= FI.getIncomingArgSize();
2736}
2737
2738SDValue
2739MipsTargetLowering::passArgOnStack(SDValue StackPtr, unsigned Offset,
2740                                   SDValue Chain, SDValue Arg, DebugLoc DL,
2741                                   bool IsTailCall, SelectionDAG &DAG) const {
2742  if (!IsTailCall) {
2743    SDValue PtrOff = DAG.getNode(ISD::ADD, DL, getPointerTy(), StackPtr,
2744                                 DAG.getIntPtrConstant(Offset));
2745    return DAG.getStore(Chain, DL, Arg, PtrOff, MachinePointerInfo(), false,
2746                        false, 0);
2747  }
2748
2749  MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo();
2750  int FI = MFI->CreateFixedObject(Arg.getValueSizeInBits() / 8, Offset, false);
2751  SDValue FIN = DAG.getFrameIndex(FI, getPointerTy());
2752  return DAG.getStore(Chain, DL, Arg, FIN, MachinePointerInfo(),
2753                      /*isVolatile=*/ true, false, 0);
2754}
2755
2756/// LowerCall - functions arguments are copied from virtual regs to
2757/// (physical regs)/(stack frame), CALLSEQ_START and CALLSEQ_END are emitted.
2758SDValue
2759MipsTargetLowering::LowerCall(TargetLowering::CallLoweringInfo &CLI,
2760                              SmallVectorImpl<SDValue> &InVals) const {
2761  SelectionDAG &DAG                     = CLI.DAG;
2762  DebugLoc &dl                          = CLI.DL;
2763  SmallVector<ISD::OutputArg, 32> &Outs = CLI.Outs;
2764  SmallVector<SDValue, 32> &OutVals     = CLI.OutVals;
2765  SmallVector<ISD::InputArg, 32> &Ins   = CLI.Ins;
2766  SDValue Chain                         = CLI.Chain;
2767  SDValue Callee                        = CLI.Callee;
2768  bool &isTailCall                      = CLI.IsTailCall;
2769  CallingConv::ID CallConv              = CLI.CallConv;
2770  bool isVarArg                         = CLI.IsVarArg;
2771
2772  MachineFunction &MF = DAG.getMachineFunction();
2773  MachineFrameInfo *MFI = MF.getFrameInfo();
2774  const TargetFrameLowering *TFL = MF.getTarget().getFrameLowering();
2775  bool IsPIC = getTargetMachine().getRelocationModel() == Reloc::PIC_;
2776
2777  // Analyze operands of the call, assigning locations to each operand.
2778  SmallVector<CCValAssign, 16> ArgLocs;
2779  CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(),
2780                 getTargetMachine(), ArgLocs, *DAG.getContext());
2781  MipsCC MipsCCInfo(CallConv, isVarArg, IsO32, CCInfo);
2782
2783  MipsCCInfo.analyzeCallOperands(Outs);
2784
2785  // Get a count of how many bytes are to be pushed on the stack.
2786  unsigned NextStackOffset = CCInfo.getNextStackOffset();
2787
2788  // Check if it's really possible to do a tail call.
2789  if (isTailCall)
2790    isTailCall =
2791      IsEligibleForTailCallOptimization(MipsCCInfo, NextStackOffset,
2792                                        *MF.getInfo<MipsFunctionInfo>());
2793
2794  if (isTailCall)
2795    ++NumTailCalls;
2796
2797  // Chain is the output chain of the last Load/Store or CopyToReg node.
2798  // ByValChain is the output chain of the last Memcpy node created for copying
2799  // byval arguments to the stack.
2800  unsigned StackAlignment = TFL->getStackAlignment();
2801  NextStackOffset = RoundUpToAlignment(NextStackOffset, StackAlignment);
2802  SDValue NextStackOffsetVal = DAG.getIntPtrConstant(NextStackOffset, true);
2803
2804  if (!isTailCall)
2805    Chain = DAG.getCALLSEQ_START(Chain, NextStackOffsetVal);
2806
2807  SDValue StackPtr = DAG.getCopyFromReg(Chain, dl,
2808                                        IsN64 ? Mips::SP_64 : Mips::SP,
2809                                        getPointerTy());
2810
2811  // With EABI is it possible to have 16 args on registers.
2812  SmallVector<std::pair<unsigned, SDValue>, 16> RegsToPass;
2813  SmallVector<SDValue, 8> MemOpChains;
2814  MipsCC::byval_iterator ByValArg = MipsCCInfo.byval_begin();
2815
2816  // Walk the register/memloc assignments, inserting copies/loads.
2817  for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
2818    SDValue Arg = OutVals[i];
2819    CCValAssign &VA = ArgLocs[i];
2820    MVT ValVT = VA.getValVT(), LocVT = VA.getLocVT();
2821    ISD::ArgFlagsTy Flags = Outs[i].Flags;
2822
2823    // ByVal Arg.
2824    if (Flags.isByVal()) {
2825      assert(Flags.getByValSize() &&
2826             "ByVal args of size 0 should have been ignored by front-end.");
2827      assert(ByValArg != MipsCCInfo.byval_end());
2828      assert(!isTailCall &&
2829             "Do not tail-call optimize if there is a byval argument.");
2830      passByValArg(Chain, dl, RegsToPass, MemOpChains, StackPtr, MFI, DAG, Arg,
2831                   MipsCCInfo, *ByValArg, Flags, Subtarget->isLittle());
2832      ++ByValArg;
2833      continue;
2834    }
2835
2836    // Promote the value if needed.
2837    switch (VA.getLocInfo()) {
2838    default: llvm_unreachable("Unknown loc info!");
2839    case CCValAssign::Full:
2840      if (VA.isRegLoc()) {
2841        if ((ValVT == MVT::f32 && LocVT == MVT::i32) ||
2842            (ValVT == MVT::f64 && LocVT == MVT::i64))
2843          Arg = DAG.getNode(ISD::BITCAST, dl, LocVT, Arg);
2844        else if (ValVT == MVT::f64 && LocVT == MVT::i32) {
2845          SDValue Lo = DAG.getNode(MipsISD::ExtractElementF64, dl, MVT::i32,
2846                                   Arg, DAG.getConstant(0, MVT::i32));
2847          SDValue Hi = DAG.getNode(MipsISD::ExtractElementF64, dl, MVT::i32,
2848                                   Arg, DAG.getConstant(1, MVT::i32));
2849          if (!Subtarget->isLittle())
2850            std::swap(Lo, Hi);
2851          unsigned LocRegLo = VA.getLocReg();
2852          unsigned LocRegHigh = getNextIntArgReg(LocRegLo);
2853          RegsToPass.push_back(std::make_pair(LocRegLo, Lo));
2854          RegsToPass.push_back(std::make_pair(LocRegHigh, Hi));
2855          continue;
2856        }
2857      }
2858      break;
2859    case CCValAssign::SExt:
2860      Arg = DAG.getNode(ISD::SIGN_EXTEND, dl, LocVT, Arg);
2861      break;
2862    case CCValAssign::ZExt:
2863      Arg = DAG.getNode(ISD::ZERO_EXTEND, dl, LocVT, Arg);
2864      break;
2865    case CCValAssign::AExt:
2866      Arg = DAG.getNode(ISD::ANY_EXTEND, dl, LocVT, Arg);
2867      break;
2868    }
2869
2870    // Arguments that can be passed on register must be kept at
2871    // RegsToPass vector
2872    if (VA.isRegLoc()) {
2873      RegsToPass.push_back(std::make_pair(VA.getLocReg(), Arg));
2874      continue;
2875    }
2876
2877    // Register can't get to this point...
2878    assert(VA.isMemLoc());
2879
2880    // emit ISD::STORE whichs stores the
2881    // parameter value to a stack Location
2882    MemOpChains.push_back(passArgOnStack(StackPtr, VA.getLocMemOffset(),
2883                                         Chain, Arg, dl, isTailCall, DAG));
2884  }
2885
2886  // Transform all store nodes into one single node because all store
2887  // nodes are independent of each other.
2888  if (!MemOpChains.empty())
2889    Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
2890                        &MemOpChains[0], MemOpChains.size());
2891
2892  // If the callee is a GlobalAddress/ExternalSymbol node (quite common, every
2893  // direct call is) turn it into a TargetGlobalAddress/TargetExternalSymbol
2894  // node so that legalize doesn't hack it.
2895  bool IsPICCall = (IsN64 || IsPIC); // true if calls are translated to jalr $25
2896  bool GlobalOrExternal = false, InternalLinkage = false;
2897  SDValue CalleeLo;
2898
2899  if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee)) {
2900    if (IsPICCall) {
2901      InternalLinkage = G->getGlobal()->hasInternalLinkage();
2902
2903      if (InternalLinkage)
2904        Callee = getAddrLocal(Callee, DAG, HasMips64);
2905      else if (LargeGOT)
2906        Callee = getAddrGlobalLargeGOT(Callee, DAG, MipsII::MO_CALL_HI16,
2907                                       MipsII::MO_CALL_LO16);
2908      else
2909        Callee = getAddrGlobal(Callee, DAG, MipsII::MO_GOT_CALL);
2910    } else
2911      Callee = DAG.getTargetGlobalAddress(G->getGlobal(), dl, getPointerTy(), 0,
2912                                          MipsII::MO_NO_FLAG);
2913    GlobalOrExternal = true;
2914  }
2915  else if (ExternalSymbolSDNode *S = dyn_cast<ExternalSymbolSDNode>(Callee)) {
2916    if (!IsN64 && !IsPIC) // !N64 && static
2917      Callee = DAG.getTargetExternalSymbol(S->getSymbol(), getPointerTy(),
2918                                            MipsII::MO_NO_FLAG);
2919    else if (LargeGOT)
2920      Callee = getAddrGlobalLargeGOT(Callee, DAG, MipsII::MO_CALL_HI16,
2921                                     MipsII::MO_CALL_LO16);
2922    else if (HasMips64)
2923      Callee = getAddrGlobal(Callee, DAG, MipsII::MO_GOT_DISP);
2924    else // O32 & PIC
2925      Callee = getAddrGlobal(Callee, DAG, MipsII::MO_GOT_CALL);
2926
2927    GlobalOrExternal = true;
2928  }
2929
2930  SDValue InFlag;
2931
2932  // T9 register operand.
2933  SDValue T9;
2934
2935  // T9 should contain the address of the callee function if
2936  // -reloction-model=pic or it is an indirect call.
2937  if (IsPICCall || !GlobalOrExternal) {
2938    // copy to T9
2939    unsigned T9Reg = IsN64 ? Mips::T9_64 : Mips::T9;
2940    Chain = DAG.getCopyToReg(Chain, dl, T9Reg, Callee, SDValue(0, 0));
2941    InFlag = Chain.getValue(1);
2942
2943    if (Subtarget->inMips16Mode())
2944      T9 = DAG.getRegister(T9Reg, getPointerTy());
2945    else
2946      Callee = DAG.getRegister(T9Reg, getPointerTy());
2947  }
2948
2949  // Insert node "GP copy globalreg" before call to function.
2950  //
2951  // R_MIPS_CALL* operators (emitted when non-internal functions are called
2952  // in PIC mode) allow symbols to be resolved via lazy binding.
2953  // The lazy binding stub requires GP to point to the GOT.
2954  if (IsPICCall && !InternalLinkage) {
2955    unsigned GPReg = IsN64 ? Mips::GP_64 : Mips::GP;
2956    EVT Ty = IsN64 ? MVT::i64 : MVT::i32;
2957    RegsToPass.push_back(std::make_pair(GPReg, GetGlobalReg(DAG, Ty)));
2958  }
2959
2960  // Build a sequence of copy-to-reg nodes chained together with token
2961  // chain and flag operands which copy the outgoing args into registers.
2962  // The InFlag in necessary since all emitted instructions must be
2963  // stuck together.
2964  for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i) {
2965    Chain = DAG.getCopyToReg(Chain, dl, RegsToPass[i].first,
2966                             RegsToPass[i].second, InFlag);
2967    InFlag = Chain.getValue(1);
2968  }
2969
2970  // MipsJmpLink = #chain, #target_address, #opt_in_flags...
2971  //             = Chain, Callee, Reg#1, Reg#2, ...
2972  //
2973  // Returns a chain & a flag for retval copy to use.
2974  SDVTList NodeTys = DAG.getVTList(MVT::Other, MVT::Glue);
2975  SmallVector<SDValue, 8> Ops;
2976  Ops.push_back(Chain);
2977  Ops.push_back(Callee);
2978
2979  // Add argument registers to the end of the list so that they are
2980  // known live into the call.
2981  for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i)
2982    Ops.push_back(DAG.getRegister(RegsToPass[i].first,
2983                                  RegsToPass[i].second.getValueType()));
2984
2985  // Add T9 register operand.
2986  if (T9.getNode())
2987    Ops.push_back(T9);
2988
2989  // Add a register mask operand representing the call-preserved registers.
2990  const TargetRegisterInfo *TRI = getTargetMachine().getRegisterInfo();
2991  const uint32_t *Mask = TRI->getCallPreservedMask(CallConv);
2992  assert(Mask && "Missing call preserved mask for calling convention");
2993  Ops.push_back(DAG.getRegisterMask(Mask));
2994
2995  if (InFlag.getNode())
2996    Ops.push_back(InFlag);
2997
2998  if (isTailCall)
2999    return DAG.getNode(MipsISD::TailCall, dl, MVT::Other, &Ops[0], Ops.size());
3000
3001  Chain  = DAG.getNode(MipsISD::JmpLink, dl, NodeTys, &Ops[0], Ops.size());
3002  InFlag = Chain.getValue(1);
3003
3004  // Create the CALLSEQ_END node.
3005  Chain = DAG.getCALLSEQ_END(Chain, NextStackOffsetVal,
3006                             DAG.getIntPtrConstant(0, true), InFlag);
3007  InFlag = Chain.getValue(1);
3008
3009  // Handle result values, copying them out of physregs into vregs that we
3010  // return.
3011  return LowerCallResult(Chain, InFlag, CallConv, isVarArg,
3012                         Ins, dl, DAG, InVals);
3013}
3014
3015/// LowerCallResult - Lower the result values of a call into the
3016/// appropriate copies out of appropriate physical registers.
3017SDValue
3018MipsTargetLowering::LowerCallResult(SDValue Chain, SDValue InFlag,
3019                                    CallingConv::ID CallConv, bool isVarArg,
3020                                    const SmallVectorImpl<ISD::InputArg> &Ins,
3021                                    DebugLoc dl, SelectionDAG &DAG,
3022                                    SmallVectorImpl<SDValue> &InVals) const {
3023  // Assign locations to each value returned by this call.
3024  SmallVector<CCValAssign, 16> RVLocs;
3025  CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(),
3026                 getTargetMachine(), RVLocs, *DAG.getContext());
3027
3028  CCInfo.AnalyzeCallResult(Ins, RetCC_Mips);
3029
3030  // Copy all of the result registers out of their specified physreg.
3031  for (unsigned i = 0; i != RVLocs.size(); ++i) {
3032    Chain = DAG.getCopyFromReg(Chain, dl, RVLocs[i].getLocReg(),
3033                               RVLocs[i].getValVT(), InFlag).getValue(1);
3034    InFlag = Chain.getValue(2);
3035    InVals.push_back(Chain.getValue(0));
3036  }
3037
3038  return Chain;
3039}
3040
3041//===----------------------------------------------------------------------===//
3042//             Formal Arguments Calling Convention Implementation
3043//===----------------------------------------------------------------------===//
3044/// LowerFormalArguments - transform physical registers into virtual registers
3045/// and generate load operations for arguments places on the stack.
3046SDValue
3047MipsTargetLowering::LowerFormalArguments(SDValue Chain,
3048                                         CallingConv::ID CallConv,
3049                                         bool isVarArg,
3050                                      const SmallVectorImpl<ISD::InputArg> &Ins,
3051                                         DebugLoc dl, SelectionDAG &DAG,
3052                                         SmallVectorImpl<SDValue> &InVals)
3053                                          const {
3054  MachineFunction &MF = DAG.getMachineFunction();
3055  MachineFrameInfo *MFI = MF.getFrameInfo();
3056  MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
3057
3058  MipsFI->setVarArgsFrameIndex(0);
3059
3060  // Used with vargs to acumulate store chains.
3061  std::vector<SDValue> OutChains;
3062
3063  // Assign locations to all of the incoming arguments.
3064  SmallVector<CCValAssign, 16> ArgLocs;
3065  CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(),
3066                 getTargetMachine(), ArgLocs, *DAG.getContext());
3067  MipsCC MipsCCInfo(CallConv, isVarArg, IsO32, CCInfo);
3068
3069  MipsCCInfo.analyzeFormalArguments(Ins);
3070  MipsFI->setFormalArgInfo(CCInfo.getNextStackOffset(),
3071                           MipsCCInfo.hasByValArg());
3072
3073  Function::const_arg_iterator FuncArg =
3074    DAG.getMachineFunction().getFunction()->arg_begin();
3075  unsigned CurArgIdx = 0;
3076  MipsCC::byval_iterator ByValArg = MipsCCInfo.byval_begin();
3077
3078  for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
3079    CCValAssign &VA = ArgLocs[i];
3080    std::advance(FuncArg, Ins[i].OrigArgIndex - CurArgIdx);
3081    CurArgIdx = Ins[i].OrigArgIndex;
3082    EVT ValVT = VA.getValVT();
3083    ISD::ArgFlagsTy Flags = Ins[i].Flags;
3084    bool IsRegLoc = VA.isRegLoc();
3085
3086    if (Flags.isByVal()) {
3087      assert(Flags.getByValSize() &&
3088             "ByVal args of size 0 should have been ignored by front-end.");
3089      assert(ByValArg != MipsCCInfo.byval_end());
3090      copyByValRegs(Chain, dl, OutChains, DAG, Flags, InVals, &*FuncArg,
3091                    MipsCCInfo, *ByValArg);
3092      ++ByValArg;
3093      continue;
3094    }
3095
3096    // Arguments stored on registers
3097    if (IsRegLoc) {
3098      EVT RegVT = VA.getLocVT();
3099      unsigned ArgReg = VA.getLocReg();
3100      const TargetRegisterClass *RC;
3101
3102      if (RegVT == MVT::i32)
3103        RC = &Mips::CPURegsRegClass;
3104      else if (RegVT == MVT::i64)
3105        RC = &Mips::CPU64RegsRegClass;
3106      else if (RegVT == MVT::f32)
3107        RC = &Mips::FGR32RegClass;
3108      else if (RegVT == MVT::f64)
3109        RC = HasMips64 ? &Mips::FGR64RegClass : &Mips::AFGR64RegClass;
3110      else
3111        llvm_unreachable("RegVT not supported by FormalArguments Lowering");
3112
3113      // Transform the arguments stored on
3114      // physical registers into virtual ones
3115      unsigned Reg = AddLiveIn(DAG.getMachineFunction(), ArgReg, RC);
3116      SDValue ArgValue = DAG.getCopyFromReg(Chain, dl, Reg, RegVT);
3117
3118      // If this is an 8 or 16-bit value, it has been passed promoted
3119      // to 32 bits.  Insert an assert[sz]ext to capture this, then
3120      // truncate to the right size.
3121      if (VA.getLocInfo() != CCValAssign::Full) {
3122        unsigned Opcode = 0;
3123        if (VA.getLocInfo() == CCValAssign::SExt)
3124          Opcode = ISD::AssertSext;
3125        else if (VA.getLocInfo() == CCValAssign::ZExt)
3126          Opcode = ISD::AssertZext;
3127        if (Opcode)
3128          ArgValue = DAG.getNode(Opcode, dl, RegVT, ArgValue,
3129                                 DAG.getValueType(ValVT));
3130        ArgValue = DAG.getNode(ISD::TRUNCATE, dl, ValVT, ArgValue);
3131      }
3132
3133      // Handle floating point arguments passed in integer registers.
3134      if ((RegVT == MVT::i32 && ValVT == MVT::f32) ||
3135          (RegVT == MVT::i64 && ValVT == MVT::f64))
3136        ArgValue = DAG.getNode(ISD::BITCAST, dl, ValVT, ArgValue);
3137      else if (IsO32 && RegVT == MVT::i32 && ValVT == MVT::f64) {
3138        unsigned Reg2 = AddLiveIn(DAG.getMachineFunction(),
3139                                  getNextIntArgReg(ArgReg), RC);
3140        SDValue ArgValue2 = DAG.getCopyFromReg(Chain, dl, Reg2, RegVT);
3141        if (!Subtarget->isLittle())
3142          std::swap(ArgValue, ArgValue2);
3143        ArgValue = DAG.getNode(MipsISD::BuildPairF64, dl, MVT::f64,
3144                               ArgValue, ArgValue2);
3145      }
3146
3147      InVals.push_back(ArgValue);
3148    } else { // VA.isRegLoc()
3149
3150      // sanity check
3151      assert(VA.isMemLoc());
3152
3153      // The stack pointer offset is relative to the caller stack frame.
3154      int FI = MFI->CreateFixedObject(ValVT.getSizeInBits()/8,
3155                                      VA.getLocMemOffset(), true);
3156
3157      // Create load nodes to retrieve arguments from the stack
3158      SDValue FIN = DAG.getFrameIndex(FI, getPointerTy());
3159      InVals.push_back(DAG.getLoad(ValVT, dl, Chain, FIN,
3160                                   MachinePointerInfo::getFixedStack(FI),
3161                                   false, false, false, 0));
3162    }
3163  }
3164
3165  // The mips ABIs for returning structs by value requires that we copy
3166  // the sret argument into $v0 for the return. Save the argument into
3167  // a virtual register so that we can access it from the return points.
3168  if (DAG.getMachineFunction().getFunction()->hasStructRetAttr()) {
3169    unsigned Reg = MipsFI->getSRetReturnReg();
3170    if (!Reg) {
3171      Reg = MF.getRegInfo().
3172        createVirtualRegister(getRegClassFor(IsN64 ? MVT::i64 : MVT::i32));
3173      MipsFI->setSRetReturnReg(Reg);
3174    }
3175    SDValue Copy = DAG.getCopyToReg(DAG.getEntryNode(), dl, Reg, InVals[0]);
3176    Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Copy, Chain);
3177  }
3178
3179  if (isVarArg)
3180    writeVarArgRegs(OutChains, MipsCCInfo, Chain, dl, DAG);
3181
3182  // All stores are grouped in one node to allow the matching between
3183  // the size of Ins and InVals. This only happens when on varg functions
3184  if (!OutChains.empty()) {
3185    OutChains.push_back(Chain);
3186    Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
3187                        &OutChains[0], OutChains.size());
3188  }
3189
3190  return Chain;
3191}
3192
3193//===----------------------------------------------------------------------===//
3194//               Return Value Calling Convention Implementation
3195//===----------------------------------------------------------------------===//
3196
3197bool
3198MipsTargetLowering::CanLowerReturn(CallingConv::ID CallConv,
3199                                   MachineFunction &MF, bool isVarArg,
3200                                   const SmallVectorImpl<ISD::OutputArg> &Outs,
3201                                   LLVMContext &Context) const {
3202  SmallVector<CCValAssign, 16> RVLocs;
3203  CCState CCInfo(CallConv, isVarArg, MF, getTargetMachine(),
3204                 RVLocs, Context);
3205  return CCInfo.CheckReturn(Outs, RetCC_Mips);
3206}
3207
3208SDValue
3209MipsTargetLowering::LowerReturn(SDValue Chain,
3210                                CallingConv::ID CallConv, bool isVarArg,
3211                                const SmallVectorImpl<ISD::OutputArg> &Outs,
3212                                const SmallVectorImpl<SDValue> &OutVals,
3213                                DebugLoc dl, SelectionDAG &DAG) const {
3214
3215  // CCValAssign - represent the assignment of
3216  // the return value to a location
3217  SmallVector<CCValAssign, 16> RVLocs;
3218
3219  // CCState - Info about the registers and stack slot.
3220  CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(),
3221                 getTargetMachine(), RVLocs, *DAG.getContext());
3222
3223  // Analize return values.
3224  CCInfo.AnalyzeReturn(Outs, RetCC_Mips);
3225
3226  // If this is the first return lowered for this function, add
3227  // the regs to the liveout set for the function.
3228  if (DAG.getMachineFunction().getRegInfo().liveout_empty()) {
3229    for (unsigned i = 0; i != RVLocs.size(); ++i)
3230      if (RVLocs[i].isRegLoc())
3231        DAG.getMachineFunction().getRegInfo().addLiveOut(RVLocs[i].getLocReg());
3232  }
3233
3234  SDValue Flag;
3235
3236  // Copy the result values into the output registers.
3237  for (unsigned i = 0; i != RVLocs.size(); ++i) {
3238    CCValAssign &VA = RVLocs[i];
3239    assert(VA.isRegLoc() && "Can only return in registers!");
3240
3241    Chain = DAG.getCopyToReg(Chain, dl, VA.getLocReg(), OutVals[i], Flag);
3242
3243    // guarantee that all emitted copies are
3244    // stuck together, avoiding something bad
3245    Flag = Chain.getValue(1);
3246  }
3247
3248  // The mips ABIs for returning structs by value requires that we copy
3249  // the sret argument into $v0 for the return. We saved the argument into
3250  // a virtual register in the entry block, so now we copy the value out
3251  // and into $v0.
3252  if (DAG.getMachineFunction().getFunction()->hasStructRetAttr()) {
3253    MachineFunction &MF      = DAG.getMachineFunction();
3254    MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
3255    unsigned Reg = MipsFI->getSRetReturnReg();
3256
3257    if (!Reg)
3258      llvm_unreachable("sret virtual register not created in the entry block");
3259    SDValue Val = DAG.getCopyFromReg(Chain, dl, Reg, getPointerTy());
3260    unsigned V0 = IsN64 ? Mips::V0_64 : Mips::V0;
3261
3262    Chain = DAG.getCopyToReg(Chain, dl, V0, Val, Flag);
3263    Flag = Chain.getValue(1);
3264    MF.getRegInfo().addLiveOut(V0);
3265  }
3266
3267  // Return on Mips is always a "jr $ra"
3268  if (Flag.getNode())
3269    return DAG.getNode(MipsISD::Ret, dl, MVT::Other, Chain, Flag);
3270
3271  // Return Void
3272  return DAG.getNode(MipsISD::Ret, dl, MVT::Other, Chain);
3273}
3274
3275//===----------------------------------------------------------------------===//
3276//                           Mips Inline Assembly Support
3277//===----------------------------------------------------------------------===//
3278
3279/// getConstraintType - Given a constraint letter, return the type of
3280/// constraint it is for this target.
3281MipsTargetLowering::ConstraintType MipsTargetLowering::
3282getConstraintType(const std::string &Constraint) const
3283{
3284  // Mips specific constrainy
3285  // GCC config/mips/constraints.md
3286  //
3287  // 'd' : An address register. Equivalent to r
3288  //       unless generating MIPS16 code.
3289  // 'y' : Equivalent to r; retained for
3290  //       backwards compatibility.
3291  // 'c' : A register suitable for use in an indirect
3292  //       jump. This will always be $25 for -mabicalls.
3293  // 'l' : The lo register. 1 word storage.
3294  // 'x' : The hilo register pair. Double word storage.
3295  if (Constraint.size() == 1) {
3296    switch (Constraint[0]) {
3297      default : break;
3298      case 'd':
3299      case 'y':
3300      case 'f':
3301      case 'c':
3302      case 'l':
3303      case 'x':
3304        return C_RegisterClass;
3305    }
3306  }
3307  return TargetLowering::getConstraintType(Constraint);
3308}
3309
3310/// Examine constraint type and operand type and determine a weight value.
3311/// This object must already have been set up with the operand type
3312/// and the current alternative constraint selected.
3313TargetLowering::ConstraintWeight
3314MipsTargetLowering::getSingleConstraintMatchWeight(
3315    AsmOperandInfo &info, const char *constraint) const {
3316  ConstraintWeight weight = CW_Invalid;
3317  Value *CallOperandVal = info.CallOperandVal;
3318    // If we don't have a value, we can't do a match,
3319    // but allow it at the lowest weight.
3320  if (CallOperandVal == NULL)
3321    return CW_Default;
3322  Type *type = CallOperandVal->getType();
3323  // Look at the constraint type.
3324  switch (*constraint) {
3325  default:
3326    weight = TargetLowering::getSingleConstraintMatchWeight(info, constraint);
3327    break;
3328  case 'd':
3329  case 'y':
3330    if (type->isIntegerTy())
3331      weight = CW_Register;
3332    break;
3333  case 'f':
3334    if (type->isFloatTy())
3335      weight = CW_Register;
3336    break;
3337  case 'c': // $25 for indirect jumps
3338  case 'l': // lo register
3339  case 'x': // hilo register pair
3340      if (type->isIntegerTy())
3341      weight = CW_SpecificReg;
3342      break;
3343  case 'I': // signed 16 bit immediate
3344  case 'J': // integer zero
3345  case 'K': // unsigned 16 bit immediate
3346  case 'L': // signed 32 bit immediate where lower 16 bits are 0
3347  case 'N': // immediate in the range of -65535 to -1 (inclusive)
3348  case 'O': // signed 15 bit immediate (+- 16383)
3349  case 'P': // immediate in the range of 65535 to 1 (inclusive)
3350    if (isa<ConstantInt>(CallOperandVal))
3351      weight = CW_Constant;
3352    break;
3353  }
3354  return weight;
3355}
3356
3357/// Given a register class constraint, like 'r', if this corresponds directly
3358/// to an LLVM register class, return a register of 0 and the register class
3359/// pointer.
3360std::pair<unsigned, const TargetRegisterClass*> MipsTargetLowering::
3361getRegForInlineAsmConstraint(const std::string &Constraint, EVT VT) const
3362{
3363  if (Constraint.size() == 1) {
3364    switch (Constraint[0]) {
3365    case 'd': // Address register. Same as 'r' unless generating MIPS16 code.
3366    case 'y': // Same as 'r'. Exists for compatibility.
3367    case 'r':
3368      if (VT == MVT::i32 || VT == MVT::i16 || VT == MVT::i8) {
3369        if (Subtarget->inMips16Mode())
3370          return std::make_pair(0U, &Mips::CPU16RegsRegClass);
3371        return std::make_pair(0U, &Mips::CPURegsRegClass);
3372      }
3373      if (VT == MVT::i64 && !HasMips64)
3374        return std::make_pair(0U, &Mips::CPURegsRegClass);
3375      if (VT == MVT::i64 && HasMips64)
3376        return std::make_pair(0U, &Mips::CPU64RegsRegClass);
3377      // This will generate an error message
3378      return std::make_pair(0u, static_cast<const TargetRegisterClass*>(0));
3379    case 'f':
3380      if (VT == MVT::f32)
3381        return std::make_pair(0U, &Mips::FGR32RegClass);
3382      if ((VT == MVT::f64) && (!Subtarget->isSingleFloat())) {
3383        if (Subtarget->isFP64bit())
3384          return std::make_pair(0U, &Mips::FGR64RegClass);
3385        return std::make_pair(0U, &Mips::AFGR64RegClass);
3386      }
3387      break;
3388    case 'c': // register suitable for indirect jump
3389      if (VT == MVT::i32)
3390        return std::make_pair((unsigned)Mips::T9, &Mips::CPURegsRegClass);
3391      assert(VT == MVT::i64 && "Unexpected type.");
3392      return std::make_pair((unsigned)Mips::T9_64, &Mips::CPU64RegsRegClass);
3393    case 'l': // register suitable for indirect jump
3394      if (VT == MVT::i32)
3395        return std::make_pair((unsigned)Mips::LO, &Mips::HILORegClass);
3396      return std::make_pair((unsigned)Mips::LO64, &Mips::HILO64RegClass);
3397    case 'x': // register suitable for indirect jump
3398      // Fixme: Not triggering the use of both hi and low
3399      // This will generate an error message
3400      return std::make_pair(0u, static_cast<const TargetRegisterClass*>(0));
3401    }
3402  }
3403  return TargetLowering::getRegForInlineAsmConstraint(Constraint, VT);
3404}
3405
3406/// LowerAsmOperandForConstraint - Lower the specified operand into the Ops
3407/// vector.  If it is invalid, don't add anything to Ops.
3408void MipsTargetLowering::LowerAsmOperandForConstraint(SDValue Op,
3409                                                     std::string &Constraint,
3410                                                     std::vector<SDValue>&Ops,
3411                                                     SelectionDAG &DAG) const {
3412  SDValue Result(0, 0);
3413
3414  // Only support length 1 constraints for now.
3415  if (Constraint.length() > 1) return;
3416
3417  char ConstraintLetter = Constraint[0];
3418  switch (ConstraintLetter) {
3419  default: break; // This will fall through to the generic implementation
3420  case 'I': // Signed 16 bit constant
3421    // If this fails, the parent routine will give an error
3422    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
3423      EVT Type = Op.getValueType();
3424      int64_t Val = C->getSExtValue();
3425      if (isInt<16>(Val)) {
3426        Result = DAG.getTargetConstant(Val, Type);
3427        break;
3428      }
3429    }
3430    return;
3431  case 'J': // integer zero
3432    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
3433      EVT Type = Op.getValueType();
3434      int64_t Val = C->getZExtValue();
3435      if (Val == 0) {
3436        Result = DAG.getTargetConstant(0, Type);
3437        break;
3438      }
3439    }
3440    return;
3441  case 'K': // unsigned 16 bit immediate
3442    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
3443      EVT Type = Op.getValueType();
3444      uint64_t Val = (uint64_t)C->getZExtValue();
3445      if (isUInt<16>(Val)) {
3446        Result = DAG.getTargetConstant(Val, Type);
3447        break;
3448      }
3449    }
3450    return;
3451  case 'L': // signed 32 bit immediate where lower 16 bits are 0
3452    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
3453      EVT Type = Op.getValueType();
3454      int64_t Val = C->getSExtValue();
3455      if ((isInt<32>(Val)) && ((Val & 0xffff) == 0)){
3456        Result = DAG.getTargetConstant(Val, Type);
3457        break;
3458      }
3459    }
3460    return;
3461  case 'N': // immediate in the range of -65535 to -1 (inclusive)
3462    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
3463      EVT Type = Op.getValueType();
3464      int64_t Val = C->getSExtValue();
3465      if ((Val >= -65535) && (Val <= -1)) {
3466        Result = DAG.getTargetConstant(Val, Type);
3467        break;
3468      }
3469    }
3470    return;
3471  case 'O': // signed 15 bit immediate
3472    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
3473      EVT Type = Op.getValueType();
3474      int64_t Val = C->getSExtValue();
3475      if ((isInt<15>(Val))) {
3476        Result = DAG.getTargetConstant(Val, Type);
3477        break;
3478      }
3479    }
3480    return;
3481  case 'P': // immediate in the range of 1 to 65535 (inclusive)
3482    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
3483      EVT Type = Op.getValueType();
3484      int64_t Val = C->getSExtValue();
3485      if ((Val <= 65535) && (Val >= 1)) {
3486        Result = DAG.getTargetConstant(Val, Type);
3487        break;
3488      }
3489    }
3490    return;
3491  }
3492
3493  if (Result.getNode()) {
3494    Ops.push_back(Result);
3495    return;
3496  }
3497
3498  TargetLowering::LowerAsmOperandForConstraint(Op, Constraint, Ops, DAG);
3499}
3500
3501bool
3502MipsTargetLowering::isLegalAddressingMode(const AddrMode &AM, Type *Ty) const {
3503  // No global is ever allowed as a base.
3504  if (AM.BaseGV)
3505    return false;
3506
3507  switch (AM.Scale) {
3508  case 0: // "r+i" or just "i", depending on HasBaseReg.
3509    break;
3510  case 1:
3511    if (!AM.HasBaseReg) // allow "r+i".
3512      break;
3513    return false; // disallow "r+r" or "r+r+i".
3514  default:
3515    return false;
3516  }
3517
3518  return true;
3519}
3520
3521bool
3522MipsTargetLowering::isOffsetFoldingLegal(const GlobalAddressSDNode *GA) const {
3523  // The Mips target isn't yet aware of offsets.
3524  return false;
3525}
3526
3527EVT MipsTargetLowering::getOptimalMemOpType(uint64_t Size, unsigned DstAlign,
3528                                            unsigned SrcAlign,
3529                                            bool IsMemset, bool ZeroMemset,
3530                                            bool MemcpyStrSrc,
3531                                            MachineFunction &MF) const {
3532  if (Subtarget->hasMips64())
3533    return MVT::i64;
3534
3535  return MVT::i32;
3536}
3537
3538bool MipsTargetLowering::isFPImmLegal(const APFloat &Imm, EVT VT) const {
3539  if (VT != MVT::f32 && VT != MVT::f64)
3540    return false;
3541  if (Imm.isNegZero())
3542    return false;
3543  return Imm.isZero();
3544}
3545
3546unsigned MipsTargetLowering::getJumpTableEncoding() const {
3547  if (IsN64)
3548    return MachineJumpTableInfo::EK_GPRel64BlockAddress;
3549
3550  return TargetLowering::getJumpTableEncoding();
3551}
3552
3553MipsTargetLowering::MipsCC::MipsCC(CallingConv::ID CallConv, bool IsVarArg,
3554                                   bool IsO32, CCState &Info) : CCInfo(Info) {
3555  UseRegsForByval = true;
3556
3557  if (IsO32) {
3558    RegSize = 4;
3559    NumIntArgRegs = array_lengthof(O32IntRegs);
3560    ReservedArgArea = 16;
3561    IntArgRegs = ShadowRegs = O32IntRegs;
3562    FixedFn = VarFn = CC_MipsO32;
3563  } else {
3564    RegSize = 8;
3565    NumIntArgRegs = array_lengthof(Mips64IntRegs);
3566    ReservedArgArea = 0;
3567    IntArgRegs = Mips64IntRegs;
3568    ShadowRegs = Mips64DPRegs;
3569    FixedFn = CC_MipsN;
3570    VarFn = CC_MipsN_VarArg;
3571  }
3572
3573  if (CallConv == CallingConv::Fast) {
3574    assert(!IsVarArg);
3575    UseRegsForByval = false;
3576    ReservedArgArea = 0;
3577    FixedFn = VarFn = CC_Mips_FastCC;
3578  }
3579
3580  // Pre-allocate reserved argument area.
3581  CCInfo.AllocateStack(ReservedArgArea, 1);
3582}
3583
3584void MipsTargetLowering::MipsCC::
3585analyzeCallOperands(const SmallVectorImpl<ISD::OutputArg> &Args) {
3586  unsigned NumOpnds = Args.size();
3587
3588  for (unsigned I = 0; I != NumOpnds; ++I) {
3589    MVT ArgVT = Args[I].VT;
3590    ISD::ArgFlagsTy ArgFlags = Args[I].Flags;
3591    bool R;
3592
3593    if (ArgFlags.isByVal()) {
3594      handleByValArg(I, ArgVT, ArgVT, CCValAssign::Full, ArgFlags);
3595      continue;
3596    }
3597
3598    if (Args[I].IsFixed)
3599      R = FixedFn(I, ArgVT, ArgVT, CCValAssign::Full, ArgFlags, CCInfo);
3600    else
3601      R = VarFn(I, ArgVT, ArgVT, CCValAssign::Full, ArgFlags, CCInfo);
3602
3603    if (R) {
3604#ifndef NDEBUG
3605      dbgs() << "Call operand #" << I << " has unhandled type "
3606             << EVT(ArgVT).getEVTString();
3607#endif
3608      llvm_unreachable(0);
3609    }
3610  }
3611}
3612
3613void MipsTargetLowering::MipsCC::
3614analyzeFormalArguments(const SmallVectorImpl<ISD::InputArg> &Args) {
3615  unsigned NumArgs = Args.size();
3616
3617  for (unsigned I = 0; I != NumArgs; ++I) {
3618    MVT ArgVT = Args[I].VT;
3619    ISD::ArgFlagsTy ArgFlags = Args[I].Flags;
3620
3621    if (ArgFlags.isByVal()) {
3622      handleByValArg(I, ArgVT, ArgVT, CCValAssign::Full, ArgFlags);
3623      continue;
3624    }
3625
3626    if (!FixedFn(I, ArgVT, ArgVT, CCValAssign::Full, ArgFlags, CCInfo))
3627      continue;
3628
3629#ifndef NDEBUG
3630    dbgs() << "Formal Arg #" << I << " has unhandled type "
3631           << EVT(ArgVT).getEVTString();
3632#endif
3633    llvm_unreachable(0);
3634  }
3635}
3636
3637void
3638MipsTargetLowering::MipsCC::handleByValArg(unsigned ValNo, MVT ValVT,
3639                                           MVT LocVT,
3640                                           CCValAssign::LocInfo LocInfo,
3641                                           ISD::ArgFlagsTy ArgFlags) {
3642  assert(ArgFlags.getByValSize() && "Byval argument's size shouldn't be 0.");
3643
3644  struct ByValArgInfo ByVal;
3645  unsigned ByValSize = RoundUpToAlignment(ArgFlags.getByValSize(), RegSize);
3646  unsigned Align = std::min(std::max(ArgFlags.getByValAlign(), RegSize),
3647                            RegSize * 2);
3648
3649  if (UseRegsForByval)
3650    allocateRegs(ByVal, ByValSize, Align);
3651
3652  // Allocate space on caller's stack.
3653  ByVal.Address = CCInfo.AllocateStack(ByValSize - RegSize * ByVal.NumRegs,
3654                                       Align);
3655  CCInfo.addLoc(CCValAssign::getMem(ValNo, ValVT, ByVal.Address, LocVT,
3656                                    LocInfo));
3657  ByValArgs.push_back(ByVal);
3658}
3659
3660void MipsTargetLowering::MipsCC::allocateRegs(ByValArgInfo &ByVal,
3661                                              unsigned ByValSize,
3662                                              unsigned Align) {
3663  assert(!(ByValSize % RegSize) && !(Align % RegSize) &&
3664         "Byval argument's size and alignment should be a multiple of"
3665         "RegSize.");
3666
3667  ByVal.FirstIdx = CCInfo.getFirstUnallocated(IntArgRegs, NumIntArgRegs);
3668
3669  // If Align > RegSize, the first arg register must be even.
3670  if ((Align > RegSize) && (ByVal.FirstIdx % 2)) {
3671    CCInfo.AllocateReg(IntArgRegs[ByVal.FirstIdx], ShadowRegs[ByVal.FirstIdx]);
3672    ++ByVal.FirstIdx;
3673  }
3674
3675  // Mark the registers allocated.
3676  for (unsigned I = ByVal.FirstIdx; ByValSize && (I < NumIntArgRegs);
3677       ByValSize -= RegSize, ++I, ++ByVal.NumRegs)
3678    CCInfo.AllocateReg(IntArgRegs[I], ShadowRegs[I]);
3679}
3680
3681void MipsTargetLowering::
3682copyByValRegs(SDValue Chain, DebugLoc DL, std::vector<SDValue> &OutChains,
3683              SelectionDAG &DAG, const ISD::ArgFlagsTy &Flags,
3684              SmallVectorImpl<SDValue> &InVals, const Argument *FuncArg,
3685              const MipsCC &CC, const ByValArgInfo &ByVal) const {
3686  MachineFunction &MF = DAG.getMachineFunction();
3687  MachineFrameInfo *MFI = MF.getFrameInfo();
3688  unsigned RegAreaSize = ByVal.NumRegs * CC.regSize();
3689  unsigned FrameObjSize = std::max(Flags.getByValSize(), RegAreaSize);
3690  int FrameObjOffset;
3691
3692  if (RegAreaSize)
3693    FrameObjOffset = (int)CC.reservedArgArea() -
3694      (int)((CC.numIntArgRegs() - ByVal.FirstIdx) * CC.regSize());
3695  else
3696    FrameObjOffset = ByVal.Address;
3697
3698  // Create frame object.
3699  EVT PtrTy = getPointerTy();
3700  int FI = MFI->CreateFixedObject(FrameObjSize, FrameObjOffset, true);
3701  SDValue FIN = DAG.getFrameIndex(FI, PtrTy);
3702  InVals.push_back(FIN);
3703
3704  if (!ByVal.NumRegs)
3705    return;
3706
3707  // Copy arg registers.
3708  MVT RegTy = MVT::getIntegerVT(CC.regSize() * 8);
3709  const TargetRegisterClass *RC = getRegClassFor(RegTy);
3710
3711  for (unsigned I = 0; I < ByVal.NumRegs; ++I) {
3712    unsigned ArgReg = CC.intArgRegs()[ByVal.FirstIdx + I];
3713    unsigned VReg = AddLiveIn(MF, ArgReg, RC);
3714    unsigned Offset = I * CC.regSize();
3715    SDValue StorePtr = DAG.getNode(ISD::ADD, DL, PtrTy, FIN,
3716                                   DAG.getConstant(Offset, PtrTy));
3717    SDValue Store = DAG.getStore(Chain, DL, DAG.getRegister(VReg, RegTy),
3718                                 StorePtr, MachinePointerInfo(FuncArg, Offset),
3719                                 false, false, 0);
3720    OutChains.push_back(Store);
3721  }
3722}
3723
3724// Copy byVal arg to registers and stack.
3725void MipsTargetLowering::
3726passByValArg(SDValue Chain, DebugLoc DL,
3727             SmallVector<std::pair<unsigned, SDValue>, 16> &RegsToPass,
3728             SmallVector<SDValue, 8> &MemOpChains, SDValue StackPtr,
3729             MachineFrameInfo *MFI, SelectionDAG &DAG, SDValue Arg,
3730             const MipsCC &CC, const ByValArgInfo &ByVal,
3731             const ISD::ArgFlagsTy &Flags, bool isLittle) const {
3732  unsigned ByValSize = Flags.getByValSize();
3733  unsigned Offset = 0; // Offset in # of bytes from the beginning of struct.
3734  unsigned RegSize = CC.regSize();
3735  unsigned Alignment = std::min(Flags.getByValAlign(), RegSize);
3736  EVT PtrTy = getPointerTy(), RegTy = MVT::getIntegerVT(RegSize * 8);
3737
3738  if (ByVal.NumRegs) {
3739    const uint16_t *ArgRegs = CC.intArgRegs();
3740    bool LeftoverBytes = (ByVal.NumRegs * RegSize > ByValSize);
3741    unsigned I = 0;
3742
3743    // Copy words to registers.
3744    for (; I < ByVal.NumRegs - LeftoverBytes; ++I, Offset += RegSize) {
3745      SDValue LoadPtr = DAG.getNode(ISD::ADD, DL, PtrTy, Arg,
3746                                    DAG.getConstant(Offset, PtrTy));
3747      SDValue LoadVal = DAG.getLoad(RegTy, DL, Chain, LoadPtr,
3748                                    MachinePointerInfo(), false, false, false,
3749                                    Alignment);
3750      MemOpChains.push_back(LoadVal.getValue(1));
3751      unsigned ArgReg = ArgRegs[ByVal.FirstIdx + I];
3752      RegsToPass.push_back(std::make_pair(ArgReg, LoadVal));
3753    }
3754
3755    // Return if the struct has been fully copied.
3756    if (ByValSize == Offset)
3757      return;
3758
3759    // Copy the remainder of the byval argument with sub-word loads and shifts.
3760    if (LeftoverBytes) {
3761      assert((ByValSize > Offset) && (ByValSize < Offset + RegSize) &&
3762             "Size of the remainder should be smaller than RegSize.");
3763      SDValue Val;
3764
3765      for (unsigned LoadSize = RegSize / 2, TotalSizeLoaded = 0;
3766           Offset < ByValSize; LoadSize /= 2) {
3767        unsigned RemSize = ByValSize - Offset;
3768
3769        if (RemSize < LoadSize)
3770          continue;
3771
3772        // Load subword.
3773        SDValue LoadPtr = DAG.getNode(ISD::ADD, DL, PtrTy, Arg,
3774                                      DAG.getConstant(Offset, PtrTy));
3775        SDValue LoadVal =
3776          DAG.getExtLoad(ISD::ZEXTLOAD, DL, RegTy, Chain, LoadPtr,
3777                         MachinePointerInfo(), MVT::getIntegerVT(LoadSize * 8),
3778                         false, false, Alignment);
3779        MemOpChains.push_back(LoadVal.getValue(1));
3780
3781        // Shift the loaded value.
3782        unsigned Shamt;
3783
3784        if (isLittle)
3785          Shamt = TotalSizeLoaded;
3786        else
3787          Shamt = (RegSize - (TotalSizeLoaded + LoadSize)) * 8;
3788
3789        SDValue Shift = DAG.getNode(ISD::SHL, DL, RegTy, LoadVal,
3790                                    DAG.getConstant(Shamt, MVT::i32));
3791
3792        if (Val.getNode())
3793          Val = DAG.getNode(ISD::OR, DL, RegTy, Val, Shift);
3794        else
3795          Val = Shift;
3796
3797        Offset += LoadSize;
3798        TotalSizeLoaded += LoadSize;
3799        Alignment = std::min(Alignment, LoadSize);
3800      }
3801
3802      unsigned ArgReg = ArgRegs[ByVal.FirstIdx + I];
3803      RegsToPass.push_back(std::make_pair(ArgReg, Val));
3804      return;
3805    }
3806  }
3807
3808  // Copy remainder of byval arg to it with memcpy.
3809  unsigned MemCpySize = ByValSize - Offset;
3810  SDValue Src = DAG.getNode(ISD::ADD, DL, PtrTy, Arg,
3811                            DAG.getConstant(Offset, PtrTy));
3812  SDValue Dst = DAG.getNode(ISD::ADD, DL, PtrTy, StackPtr,
3813                            DAG.getIntPtrConstant(ByVal.Address));
3814  Chain = DAG.getMemcpy(Chain, DL, Dst, Src,
3815                        DAG.getConstant(MemCpySize, PtrTy), Alignment,
3816                        /*isVolatile=*/false, /*AlwaysInline=*/false,
3817                        MachinePointerInfo(0), MachinePointerInfo(0));
3818  MemOpChains.push_back(Chain);
3819}
3820
3821void
3822MipsTargetLowering::writeVarArgRegs(std::vector<SDValue> &OutChains,
3823                                    const MipsCC &CC, SDValue Chain,
3824                                    DebugLoc DL, SelectionDAG &DAG) const {
3825  unsigned NumRegs = CC.numIntArgRegs();
3826  const uint16_t *ArgRegs = CC.intArgRegs();
3827  const CCState &CCInfo = CC.getCCInfo();
3828  unsigned Idx = CCInfo.getFirstUnallocated(ArgRegs, NumRegs);
3829  unsigned RegSize = CC.regSize();
3830  MVT RegTy = MVT::getIntegerVT(RegSize * 8);
3831  const TargetRegisterClass *RC = getRegClassFor(RegTy);
3832  MachineFunction &MF = DAG.getMachineFunction();
3833  MachineFrameInfo *MFI = MF.getFrameInfo();
3834  MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
3835
3836  // Offset of the first variable argument from stack pointer.
3837  int VaArgOffset;
3838
3839  if (NumRegs == Idx)
3840    VaArgOffset = RoundUpToAlignment(CCInfo.getNextStackOffset(), RegSize);
3841  else
3842    VaArgOffset =
3843      (int)CC.reservedArgArea() - (int)(RegSize * (NumRegs - Idx));
3844
3845  // Record the frame index of the first variable argument
3846  // which is a value necessary to VASTART.
3847  int FI = MFI->CreateFixedObject(RegSize, VaArgOffset, true);
3848  MipsFI->setVarArgsFrameIndex(FI);
3849
3850  // Copy the integer registers that have not been used for argument passing
3851  // to the argument register save area. For O32, the save area is allocated
3852  // in the caller's stack frame, while for N32/64, it is allocated in the
3853  // callee's stack frame.
3854  for (unsigned I = Idx; I < NumRegs; ++I, VaArgOffset += RegSize) {
3855    unsigned Reg = AddLiveIn(MF, ArgRegs[I], RC);
3856    SDValue ArgValue = DAG.getCopyFromReg(Chain, DL, Reg, RegTy);
3857    FI = MFI->CreateFixedObject(RegSize, VaArgOffset, true);
3858    SDValue PtrOff = DAG.getFrameIndex(FI, getPointerTy());
3859    SDValue Store = DAG.getStore(Chain, DL, ArgValue, PtrOff,
3860                                 MachinePointerInfo(), false, false, 0);
3861    cast<StoreSDNode>(Store.getNode())->getMemOperand()->setValue(0);
3862    OutChains.push_back(Store);
3863  }
3864}
3865