MipsISelLowering.cpp revision 6265d5c91a18b2fb6499eb581c488315880c044d
1//===-- MipsISelLowering.cpp - Mips DAG Lowering Implementation -----------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file defines the interfaces that Mips uses to lower LLVM code into a
11// selection DAG.
12//
13//===----------------------------------------------------------------------===//
14#define DEBUG_TYPE "mips-lower"
15#include "MipsISelLowering.h"
16#include "InstPrinter/MipsInstPrinter.h"
17#include "MCTargetDesc/MipsBaseInfo.h"
18#include "MipsMachineFunction.h"
19#include "MipsSubtarget.h"
20#include "MipsTargetMachine.h"
21#include "MipsTargetObjectFile.h"
22#include "llvm/ADT/Statistic.h"
23#include "llvm/CodeGen/CallingConvLower.h"
24#include "llvm/CodeGen/MachineFrameInfo.h"
25#include "llvm/CodeGen/MachineFunction.h"
26#include "llvm/CodeGen/MachineInstrBuilder.h"
27#include "llvm/CodeGen/MachineRegisterInfo.h"
28#include "llvm/CodeGen/SelectionDAGISel.h"
29#include "llvm/CodeGen/ValueTypes.h"
30#include "llvm/IR/CallingConv.h"
31#include "llvm/IR/DerivedTypes.h"
32#include "llvm/IR/GlobalVariable.h"
33#include "llvm/Support/CommandLine.h"
34#include "llvm/Support/Debug.h"
35#include "llvm/Support/ErrorHandling.h"
36#include "llvm/Support/raw_ostream.h"
37
38using namespace llvm;
39
40STATISTIC(NumTailCalls, "Number of tail calls");
41
42static cl::opt<bool>
43LargeGOT("mxgot", cl::Hidden,
44         cl::desc("MIPS: Enable GOT larger than 64k."), cl::init(false));
45
46static const uint16_t O32IntRegs[4] = {
47  Mips::A0, Mips::A1, Mips::A2, Mips::A3
48};
49
50static const uint16_t Mips64IntRegs[8] = {
51  Mips::A0_64, Mips::A1_64, Mips::A2_64, Mips::A3_64,
52  Mips::T0_64, Mips::T1_64, Mips::T2_64, Mips::T3_64
53};
54
55static const uint16_t Mips64DPRegs[8] = {
56  Mips::D12_64, Mips::D13_64, Mips::D14_64, Mips::D15_64,
57  Mips::D16_64, Mips::D17_64, Mips::D18_64, Mips::D19_64
58};
59
60// If I is a shifted mask, set the size (Size) and the first bit of the
61// mask (Pos), and return true.
62// For example, if I is 0x003ff800, (Pos, Size) = (11, 11).
63static bool isShiftedMask(uint64_t I, uint64_t &Pos, uint64_t &Size) {
64  if (!isShiftedMask_64(I))
65     return false;
66
67  Size = CountPopulation_64(I);
68  Pos = CountTrailingZeros_64(I);
69  return true;
70}
71
72SDValue MipsTargetLowering::getGlobalReg(SelectionDAG &DAG, EVT Ty) const {
73  MipsFunctionInfo *FI = DAG.getMachineFunction().getInfo<MipsFunctionInfo>();
74  return DAG.getRegister(FI->getGlobalBaseReg(), Ty);
75}
76
77static SDValue getTargetNode(SDValue Op, SelectionDAG &DAG, unsigned Flag) {
78  EVT Ty = Op.getValueType();
79
80  if (GlobalAddressSDNode *N = dyn_cast<GlobalAddressSDNode>(Op))
81    return DAG.getTargetGlobalAddress(N->getGlobal(), Op.getDebugLoc(), Ty, 0,
82                                      Flag);
83  if (ExternalSymbolSDNode *N = dyn_cast<ExternalSymbolSDNode>(Op))
84    return DAG.getTargetExternalSymbol(N->getSymbol(), Ty, Flag);
85  if (BlockAddressSDNode *N = dyn_cast<BlockAddressSDNode>(Op))
86    return DAG.getTargetBlockAddress(N->getBlockAddress(), Ty, 0, Flag);
87  if (JumpTableSDNode *N = dyn_cast<JumpTableSDNode>(Op))
88    return DAG.getTargetJumpTable(N->getIndex(), Ty, Flag);
89  if (ConstantPoolSDNode *N = dyn_cast<ConstantPoolSDNode>(Op))
90    return DAG.getTargetConstantPool(N->getConstVal(), Ty, N->getAlignment(),
91                                     N->getOffset(), Flag);
92
93  llvm_unreachable("Unexpected node type.");
94  return SDValue();
95}
96
97static SDValue getAddrNonPIC(SDValue Op, SelectionDAG &DAG) {
98  DebugLoc DL = Op.getDebugLoc();
99  EVT Ty = Op.getValueType();
100  SDValue Hi = getTargetNode(Op, DAG, MipsII::MO_ABS_HI);
101  SDValue Lo = getTargetNode(Op, DAG, MipsII::MO_ABS_LO);
102  return DAG.getNode(ISD::ADD, DL, Ty,
103                     DAG.getNode(MipsISD::Hi, DL, Ty, Hi),
104                     DAG.getNode(MipsISD::Lo, DL, Ty, Lo));
105}
106
107SDValue MipsTargetLowering::getAddrLocal(SDValue Op, SelectionDAG &DAG,
108                                         bool HasMips64) const {
109  DebugLoc DL = Op.getDebugLoc();
110  EVT Ty = Op.getValueType();
111  unsigned GOTFlag = HasMips64 ? MipsII::MO_GOT_PAGE : MipsII::MO_GOT;
112  SDValue GOT = DAG.getNode(MipsISD::Wrapper, DL, Ty, getGlobalReg(DAG, Ty),
113                            getTargetNode(Op, DAG, GOTFlag));
114  SDValue Load = DAG.getLoad(Ty, DL, DAG.getEntryNode(), GOT,
115                             MachinePointerInfo::getGOT(), false, false, false,
116                             0);
117  unsigned LoFlag = HasMips64 ? MipsII::MO_GOT_OFST : MipsII::MO_ABS_LO;
118  SDValue Lo = DAG.getNode(MipsISD::Lo, DL, Ty, getTargetNode(Op, DAG, LoFlag));
119  return DAG.getNode(ISD::ADD, DL, Ty, Load, Lo);
120}
121
122SDValue MipsTargetLowering::getAddrGlobal(SDValue Op, SelectionDAG &DAG,
123                                          unsigned Flag) const {
124  DebugLoc DL = Op.getDebugLoc();
125  EVT Ty = Op.getValueType();
126  SDValue Tgt = DAG.getNode(MipsISD::Wrapper, DL, Ty, getGlobalReg(DAG, Ty),
127                            getTargetNode(Op, DAG, Flag));
128  return DAG.getLoad(Ty, DL, DAG.getEntryNode(), Tgt,
129                     MachinePointerInfo::getGOT(), false, false, false, 0);
130}
131
132SDValue MipsTargetLowering::getAddrGlobalLargeGOT(SDValue Op, SelectionDAG &DAG,
133                                                  unsigned HiFlag,
134                                                  unsigned LoFlag) const {
135  DebugLoc DL = Op.getDebugLoc();
136  EVT Ty = Op.getValueType();
137  SDValue Hi = DAG.getNode(MipsISD::Hi, DL, Ty, getTargetNode(Op, DAG, HiFlag));
138  Hi = DAG.getNode(ISD::ADD, DL, Ty, Hi, getGlobalReg(DAG, Ty));
139  SDValue Wrapper = DAG.getNode(MipsISD::Wrapper, DL, Ty, Hi,
140                                getTargetNode(Op, DAG, LoFlag));
141  return DAG.getLoad(Ty, DL, DAG.getEntryNode(), Wrapper,
142                     MachinePointerInfo::getGOT(), false, false, false, 0);
143}
144
145const char *MipsTargetLowering::getTargetNodeName(unsigned Opcode) const {
146  switch (Opcode) {
147  case MipsISD::JmpLink:           return "MipsISD::JmpLink";
148  case MipsISD::TailCall:          return "MipsISD::TailCall";
149  case MipsISD::Hi:                return "MipsISD::Hi";
150  case MipsISD::Lo:                return "MipsISD::Lo";
151  case MipsISD::GPRel:             return "MipsISD::GPRel";
152  case MipsISD::ThreadPointer:     return "MipsISD::ThreadPointer";
153  case MipsISD::Ret:               return "MipsISD::Ret";
154  case MipsISD::EH_RETURN:         return "MipsISD::EH_RETURN";
155  case MipsISD::FPBrcond:          return "MipsISD::FPBrcond";
156  case MipsISD::FPCmp:             return "MipsISD::FPCmp";
157  case MipsISD::CMovFP_T:          return "MipsISD::CMovFP_T";
158  case MipsISD::CMovFP_F:          return "MipsISD::CMovFP_F";
159  case MipsISD::FPRound:           return "MipsISD::FPRound";
160  case MipsISD::ExtractLOHI:       return "MipsISD::ExtractLOHI";
161  case MipsISD::InsertLOHI:        return "MipsISD::InsertLOHI";
162  case MipsISD::Mult:              return "MipsISD::Mult";
163  case MipsISD::Multu:             return "MipsISD::Multu";
164  case MipsISD::MAdd:              return "MipsISD::MAdd";
165  case MipsISD::MAddu:             return "MipsISD::MAddu";
166  case MipsISD::MSub:              return "MipsISD::MSub";
167  case MipsISD::MSubu:             return "MipsISD::MSubu";
168  case MipsISD::DivRem:            return "MipsISD::DivRem";
169  case MipsISD::DivRemU:           return "MipsISD::DivRemU";
170  case MipsISD::DivRem16:          return "MipsISD::DivRem16";
171  case MipsISD::DivRemU16:         return "MipsISD::DivRemU16";
172  case MipsISD::BuildPairF64:      return "MipsISD::BuildPairF64";
173  case MipsISD::ExtractElementF64: return "MipsISD::ExtractElementF64";
174  case MipsISD::Wrapper:           return "MipsISD::Wrapper";
175  case MipsISD::Sync:              return "MipsISD::Sync";
176  case MipsISD::Ext:               return "MipsISD::Ext";
177  case MipsISD::Ins:               return "MipsISD::Ins";
178  case MipsISD::LWL:               return "MipsISD::LWL";
179  case MipsISD::LWR:               return "MipsISD::LWR";
180  case MipsISD::SWL:               return "MipsISD::SWL";
181  case MipsISD::SWR:               return "MipsISD::SWR";
182  case MipsISD::LDL:               return "MipsISD::LDL";
183  case MipsISD::LDR:               return "MipsISD::LDR";
184  case MipsISD::SDL:               return "MipsISD::SDL";
185  case MipsISD::SDR:               return "MipsISD::SDR";
186  case MipsISD::EXTP:              return "MipsISD::EXTP";
187  case MipsISD::EXTPDP:            return "MipsISD::EXTPDP";
188  case MipsISD::EXTR_S_H:          return "MipsISD::EXTR_S_H";
189  case MipsISD::EXTR_W:            return "MipsISD::EXTR_W";
190  case MipsISD::EXTR_R_W:          return "MipsISD::EXTR_R_W";
191  case MipsISD::EXTR_RS_W:         return "MipsISD::EXTR_RS_W";
192  case MipsISD::SHILO:             return "MipsISD::SHILO";
193  case MipsISD::MTHLIP:            return "MipsISD::MTHLIP";
194  case MipsISD::MULT:              return "MipsISD::MULT";
195  case MipsISD::MULTU:             return "MipsISD::MULTU";
196  case MipsISD::MADD_DSP:          return "MipsISD::MADD_DSP";
197  case MipsISD::MADDU_DSP:         return "MipsISD::MADDU_DSP";
198  case MipsISD::MSUB_DSP:          return "MipsISD::MSUB_DSP";
199  case MipsISD::MSUBU_DSP:         return "MipsISD::MSUBU_DSP";
200  case MipsISD::SHLL_DSP:          return "MipsISD::SHLL_DSP";
201  case MipsISD::SHRA_DSP:          return "MipsISD::SHRA_DSP";
202  case MipsISD::SHRL_DSP:          return "MipsISD::SHRL_DSP";
203  default:                         return NULL;
204  }
205}
206
207MipsTargetLowering::
208MipsTargetLowering(MipsTargetMachine &TM)
209  : TargetLowering(TM, new MipsTargetObjectFile()),
210    Subtarget(&TM.getSubtarget<MipsSubtarget>()),
211    HasMips64(Subtarget->hasMips64()), IsN64(Subtarget->isABI_N64()),
212    IsO32(Subtarget->isABI_O32()) {
213  // Mips does not have i1 type, so use i32 for
214  // setcc operations results (slt, sgt, ...).
215  setBooleanContents(ZeroOrOneBooleanContent);
216  setBooleanVectorContents(ZeroOrOneBooleanContent); // FIXME: Is this correct?
217
218  // Load extented operations for i1 types must be promoted
219  setLoadExtAction(ISD::EXTLOAD,  MVT::i1,  Promote);
220  setLoadExtAction(ISD::ZEXTLOAD, MVT::i1,  Promote);
221  setLoadExtAction(ISD::SEXTLOAD, MVT::i1,  Promote);
222
223  // MIPS doesn't have extending float->double load/store
224  setLoadExtAction(ISD::EXTLOAD, MVT::f32, Expand);
225  setTruncStoreAction(MVT::f64, MVT::f32, Expand);
226
227  // Used by legalize types to correctly generate the setcc result.
228  // Without this, every float setcc comes with a AND/OR with the result,
229  // we don't want this, since the fpcmp result goes to a flag register,
230  // which is used implicitly by brcond and select operations.
231  AddPromotedToType(ISD::SETCC, MVT::i1, MVT::i32);
232
233  // Mips Custom Operations
234  setOperationAction(ISD::BR_JT,              MVT::Other, Custom);
235  setOperationAction(ISD::GlobalAddress,      MVT::i32,   Custom);
236  setOperationAction(ISD::BlockAddress,       MVT::i32,   Custom);
237  setOperationAction(ISD::GlobalTLSAddress,   MVT::i32,   Custom);
238  setOperationAction(ISD::JumpTable,          MVT::i32,   Custom);
239  setOperationAction(ISD::ConstantPool,       MVT::i32,   Custom);
240  setOperationAction(ISD::SELECT,             MVT::f32,   Custom);
241  setOperationAction(ISD::SELECT,             MVT::f64,   Custom);
242  setOperationAction(ISD::SELECT,             MVT::i32,   Custom);
243  setOperationAction(ISD::SELECT_CC,          MVT::f32,   Custom);
244  setOperationAction(ISD::SELECT_CC,          MVT::f64,   Custom);
245  setOperationAction(ISD::SETCC,              MVT::f32,   Custom);
246  setOperationAction(ISD::SETCC,              MVT::f64,   Custom);
247  setOperationAction(ISD::BRCOND,             MVT::Other, Custom);
248  setOperationAction(ISD::VASTART,            MVT::Other, Custom);
249  setOperationAction(ISD::FCOPYSIGN,          MVT::f32,   Custom);
250  setOperationAction(ISD::FCOPYSIGN,          MVT::f64,   Custom);
251
252  if (!TM.Options.NoNaNsFPMath) {
253    setOperationAction(ISD::FABS,             MVT::f32,   Custom);
254    setOperationAction(ISD::FABS,             MVT::f64,   Custom);
255  }
256
257  if (HasMips64) {
258    setOperationAction(ISD::GlobalAddress,      MVT::i64,   Custom);
259    setOperationAction(ISD::BlockAddress,       MVT::i64,   Custom);
260    setOperationAction(ISD::GlobalTLSAddress,   MVT::i64,   Custom);
261    setOperationAction(ISD::JumpTable,          MVT::i64,   Custom);
262    setOperationAction(ISD::ConstantPool,       MVT::i64,   Custom);
263    setOperationAction(ISD::SELECT,             MVT::i64,   Custom);
264    setOperationAction(ISD::LOAD,               MVT::i64,   Custom);
265    setOperationAction(ISD::STORE,              MVT::i64,   Custom);
266  }
267
268  if (!HasMips64) {
269    setOperationAction(ISD::SHL_PARTS,          MVT::i32,   Custom);
270    setOperationAction(ISD::SRA_PARTS,          MVT::i32,   Custom);
271    setOperationAction(ISD::SRL_PARTS,          MVT::i32,   Custom);
272  }
273
274  setOperationAction(ISD::ADD,                MVT::i32,   Custom);
275  if (HasMips64)
276    setOperationAction(ISD::ADD,                MVT::i64,   Custom);
277
278  setOperationAction(ISD::SDIV, MVT::i32, Expand);
279  setOperationAction(ISD::SREM, MVT::i32, Expand);
280  setOperationAction(ISD::UDIV, MVT::i32, Expand);
281  setOperationAction(ISD::UREM, MVT::i32, Expand);
282  setOperationAction(ISD::SDIV, MVT::i64, Expand);
283  setOperationAction(ISD::SREM, MVT::i64, Expand);
284  setOperationAction(ISD::UDIV, MVT::i64, Expand);
285  setOperationAction(ISD::UREM, MVT::i64, Expand);
286
287  // Operations not directly supported by Mips.
288  setOperationAction(ISD::BR_CC,             MVT::f32,   Expand);
289  setOperationAction(ISD::BR_CC,             MVT::f64,   Expand);
290  setOperationAction(ISD::BR_CC,             MVT::i32,   Expand);
291  setOperationAction(ISD::BR_CC,             MVT::i64,   Expand);
292  setOperationAction(ISD::SELECT_CC,         MVT::Other, Expand);
293  setOperationAction(ISD::UINT_TO_FP,        MVT::i32,   Expand);
294  setOperationAction(ISD::UINT_TO_FP,        MVT::i64,   Expand);
295  setOperationAction(ISD::FP_TO_UINT,        MVT::i32,   Expand);
296  setOperationAction(ISD::FP_TO_UINT,        MVT::i64,   Expand);
297  setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i1,    Expand);
298  setOperationAction(ISD::CTPOP,             MVT::i32,   Expand);
299  setOperationAction(ISD::CTPOP,             MVT::i64,   Expand);
300  setOperationAction(ISD::CTTZ,              MVT::i32,   Expand);
301  setOperationAction(ISD::CTTZ,              MVT::i64,   Expand);
302  setOperationAction(ISD::CTTZ_ZERO_UNDEF,   MVT::i32,   Expand);
303  setOperationAction(ISD::CTTZ_ZERO_UNDEF,   MVT::i64,   Expand);
304  setOperationAction(ISD::CTLZ_ZERO_UNDEF,   MVT::i32,   Expand);
305  setOperationAction(ISD::CTLZ_ZERO_UNDEF,   MVT::i64,   Expand);
306  setOperationAction(ISD::ROTL,              MVT::i32,   Expand);
307  setOperationAction(ISD::ROTL,              MVT::i64,   Expand);
308  setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32,  Expand);
309  setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i64,  Expand);
310
311  if (!Subtarget->hasMips32r2())
312    setOperationAction(ISD::ROTR, MVT::i32,   Expand);
313
314  if (!Subtarget->hasMips64r2())
315    setOperationAction(ISD::ROTR, MVT::i64,   Expand);
316
317  setOperationAction(ISD::FSIN,              MVT::f32,   Expand);
318  setOperationAction(ISD::FSIN,              MVT::f64,   Expand);
319  setOperationAction(ISD::FCOS,              MVT::f32,   Expand);
320  setOperationAction(ISD::FCOS,              MVT::f64,   Expand);
321  setOperationAction(ISD::FSINCOS,           MVT::f32,   Expand);
322  setOperationAction(ISD::FSINCOS,           MVT::f64,   Expand);
323  setOperationAction(ISD::FPOWI,             MVT::f32,   Expand);
324  setOperationAction(ISD::FPOW,              MVT::f32,   Expand);
325  setOperationAction(ISD::FPOW,              MVT::f64,   Expand);
326  setOperationAction(ISD::FLOG,              MVT::f32,   Expand);
327  setOperationAction(ISD::FLOG2,             MVT::f32,   Expand);
328  setOperationAction(ISD::FLOG10,            MVT::f32,   Expand);
329  setOperationAction(ISD::FEXP,              MVT::f32,   Expand);
330  setOperationAction(ISD::FMA,               MVT::f32,   Expand);
331  setOperationAction(ISD::FMA,               MVT::f64,   Expand);
332  setOperationAction(ISD::FREM,              MVT::f32,   Expand);
333  setOperationAction(ISD::FREM,              MVT::f64,   Expand);
334
335  if (!TM.Options.NoNaNsFPMath) {
336    setOperationAction(ISD::FNEG,             MVT::f32,   Expand);
337    setOperationAction(ISD::FNEG,             MVT::f64,   Expand);
338  }
339
340  setOperationAction(ISD::EXCEPTIONADDR,     MVT::i32, Expand);
341  setOperationAction(ISD::EXCEPTIONADDR,     MVT::i64, Expand);
342  setOperationAction(ISD::EHSELECTION,       MVT::i32, Expand);
343  setOperationAction(ISD::EHSELECTION,       MVT::i64, Expand);
344
345  setOperationAction(ISD::EH_RETURN, MVT::Other, Custom);
346
347  setOperationAction(ISD::VAARG,             MVT::Other, Expand);
348  setOperationAction(ISD::VACOPY,            MVT::Other, Expand);
349  setOperationAction(ISD::VAEND,             MVT::Other, Expand);
350
351  // Use the default for now
352  setOperationAction(ISD::STACKSAVE,         MVT::Other, Expand);
353  setOperationAction(ISD::STACKRESTORE,      MVT::Other, Expand);
354
355  setOperationAction(ISD::ATOMIC_LOAD,       MVT::i32,    Expand);
356  setOperationAction(ISD::ATOMIC_LOAD,       MVT::i64,    Expand);
357  setOperationAction(ISD::ATOMIC_STORE,      MVT::i32,    Expand);
358  setOperationAction(ISD::ATOMIC_STORE,      MVT::i64,    Expand);
359
360  setInsertFencesForAtomic(true);
361
362  if (!Subtarget->hasSEInReg()) {
363    setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i8,  Expand);
364    setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i16, Expand);
365  }
366
367  if (!Subtarget->hasBitCount()) {
368    setOperationAction(ISD::CTLZ, MVT::i32, Expand);
369    setOperationAction(ISD::CTLZ, MVT::i64, Expand);
370  }
371
372  if (!Subtarget->hasSwap()) {
373    setOperationAction(ISD::BSWAP, MVT::i32, Expand);
374    setOperationAction(ISD::BSWAP, MVT::i64, Expand);
375  }
376
377  if (HasMips64) {
378    setLoadExtAction(ISD::SEXTLOAD, MVT::i32, Custom);
379    setLoadExtAction(ISD::ZEXTLOAD, MVT::i32, Custom);
380    setLoadExtAction(ISD::EXTLOAD, MVT::i32, Custom);
381    setTruncStoreAction(MVT::i64, MVT::i32, Custom);
382  }
383
384  setTargetDAGCombine(ISD::SDIVREM);
385  setTargetDAGCombine(ISD::UDIVREM);
386  setTargetDAGCombine(ISD::SELECT);
387  setTargetDAGCombine(ISD::AND);
388  setTargetDAGCombine(ISD::OR);
389  setTargetDAGCombine(ISD::ADD);
390
391  setMinFunctionAlignment(HasMips64 ? 3 : 2);
392
393  setStackPointerRegisterToSaveRestore(IsN64 ? Mips::SP_64 : Mips::SP);
394
395  setExceptionPointerRegister(IsN64 ? Mips::A0_64 : Mips::A0);
396  setExceptionSelectorRegister(IsN64 ? Mips::A1_64 : Mips::A1);
397
398  MaxStoresPerMemcpy = 16;
399}
400
401const MipsTargetLowering *MipsTargetLowering::create(MipsTargetMachine &TM) {
402  if (TM.getSubtargetImpl()->inMips16Mode())
403    return llvm::createMips16TargetLowering(TM);
404
405  return llvm::createMipsSETargetLowering(TM);
406}
407
408EVT MipsTargetLowering::getSetCCResultType(EVT VT) const {
409  if (!VT.isVector())
410    return MVT::i32;
411  return VT.changeVectorElementTypeToInteger();
412}
413
414static SDValue performDivRemCombine(SDNode *N, SelectionDAG &DAG,
415                                    TargetLowering::DAGCombinerInfo &DCI,
416                                    const MipsSubtarget *Subtarget) {
417  if (DCI.isBeforeLegalizeOps())
418    return SDValue();
419
420  EVT Ty = N->getValueType(0);
421  unsigned LO = (Ty == MVT::i32) ? Mips::LO : Mips::LO64;
422  unsigned HI = (Ty == MVT::i32) ? Mips::HI : Mips::HI64;
423  unsigned Opc = N->getOpcode() == ISD::SDIVREM ? MipsISD::DivRem16 :
424                                                  MipsISD::DivRemU16;
425  DebugLoc DL = N->getDebugLoc();
426
427  SDValue DivRem = DAG.getNode(Opc, DL, MVT::Glue,
428                               N->getOperand(0), N->getOperand(1));
429  SDValue InChain = DAG.getEntryNode();
430  SDValue InGlue = DivRem;
431
432  // insert MFLO
433  if (N->hasAnyUseOfValue(0)) {
434    SDValue CopyFromLo = DAG.getCopyFromReg(InChain, DL, LO, Ty,
435                                            InGlue);
436    DAG.ReplaceAllUsesOfValueWith(SDValue(N, 0), CopyFromLo);
437    InChain = CopyFromLo.getValue(1);
438    InGlue = CopyFromLo.getValue(2);
439  }
440
441  // insert MFHI
442  if (N->hasAnyUseOfValue(1)) {
443    SDValue CopyFromHi = DAG.getCopyFromReg(InChain, DL,
444                                            HI, Ty, InGlue);
445    DAG.ReplaceAllUsesOfValueWith(SDValue(N, 1), CopyFromHi);
446  }
447
448  return SDValue();
449}
450
451static Mips::CondCode condCodeToFCC(ISD::CondCode CC) {
452  switch (CC) {
453  default: llvm_unreachable("Unknown fp condition code!");
454  case ISD::SETEQ:
455  case ISD::SETOEQ: return Mips::FCOND_OEQ;
456  case ISD::SETUNE: return Mips::FCOND_UNE;
457  case ISD::SETLT:
458  case ISD::SETOLT: return Mips::FCOND_OLT;
459  case ISD::SETGT:
460  case ISD::SETOGT: return Mips::FCOND_OGT;
461  case ISD::SETLE:
462  case ISD::SETOLE: return Mips::FCOND_OLE;
463  case ISD::SETGE:
464  case ISD::SETOGE: return Mips::FCOND_OGE;
465  case ISD::SETULT: return Mips::FCOND_ULT;
466  case ISD::SETULE: return Mips::FCOND_ULE;
467  case ISD::SETUGT: return Mips::FCOND_UGT;
468  case ISD::SETUGE: return Mips::FCOND_UGE;
469  case ISD::SETUO:  return Mips::FCOND_UN;
470  case ISD::SETO:   return Mips::FCOND_OR;
471  case ISD::SETNE:
472  case ISD::SETONE: return Mips::FCOND_ONE;
473  case ISD::SETUEQ: return Mips::FCOND_UEQ;
474  }
475}
476
477
478/// This function returns true if the floating point conditional branches and
479/// conditional moves which use condition code CC should be inverted.
480static bool invertFPCondCodeUser(Mips::CondCode CC) {
481  if (CC >= Mips::FCOND_F && CC <= Mips::FCOND_NGT)
482    return false;
483
484  assert((CC >= Mips::FCOND_T && CC <= Mips::FCOND_GT) &&
485         "Illegal Condition Code");
486
487  return true;
488}
489
490// Creates and returns an FPCmp node from a setcc node.
491// Returns Op if setcc is not a floating point comparison.
492static SDValue createFPCmp(SelectionDAG &DAG, const SDValue &Op) {
493  // must be a SETCC node
494  if (Op.getOpcode() != ISD::SETCC)
495    return Op;
496
497  SDValue LHS = Op.getOperand(0);
498
499  if (!LHS.getValueType().isFloatingPoint())
500    return Op;
501
502  SDValue RHS = Op.getOperand(1);
503  DebugLoc DL = Op.getDebugLoc();
504
505  // Assume the 3rd operand is a CondCodeSDNode. Add code to check the type of
506  // node if necessary.
507  ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(2))->get();
508
509  return DAG.getNode(MipsISD::FPCmp, DL, MVT::Glue, LHS, RHS,
510                     DAG.getConstant(condCodeToFCC(CC), MVT::i32));
511}
512
513// Creates and returns a CMovFPT/F node.
514static SDValue createCMovFP(SelectionDAG &DAG, SDValue Cond, SDValue True,
515                            SDValue False, DebugLoc DL) {
516  ConstantSDNode *CC = cast<ConstantSDNode>(Cond.getOperand(2));
517  bool invert = invertFPCondCodeUser((Mips::CondCode)CC->getSExtValue());
518
519  return DAG.getNode((invert ? MipsISD::CMovFP_F : MipsISD::CMovFP_T), DL,
520                     True.getValueType(), True, False, Cond);
521}
522
523static SDValue performSELECTCombine(SDNode *N, SelectionDAG &DAG,
524                                    TargetLowering::DAGCombinerInfo &DCI,
525                                    const MipsSubtarget *Subtarget) {
526  if (DCI.isBeforeLegalizeOps())
527    return SDValue();
528
529  SDValue SetCC = N->getOperand(0);
530
531  if ((SetCC.getOpcode() != ISD::SETCC) ||
532      !SetCC.getOperand(0).getValueType().isInteger())
533    return SDValue();
534
535  SDValue False = N->getOperand(2);
536  EVT FalseTy = False.getValueType();
537
538  if (!FalseTy.isInteger())
539    return SDValue();
540
541  ConstantSDNode *CN = dyn_cast<ConstantSDNode>(False);
542
543  if (!CN || CN->getZExtValue())
544    return SDValue();
545
546  const DebugLoc DL = N->getDebugLoc();
547  ISD::CondCode CC = cast<CondCodeSDNode>(SetCC.getOperand(2))->get();
548  SDValue True = N->getOperand(1);
549
550  SetCC = DAG.getSetCC(DL, SetCC.getValueType(), SetCC.getOperand(0),
551                       SetCC.getOperand(1), ISD::getSetCCInverse(CC, true));
552
553  return DAG.getNode(ISD::SELECT, DL, FalseTy, SetCC, False, True);
554}
555
556static SDValue performANDCombine(SDNode *N, SelectionDAG &DAG,
557                                 TargetLowering::DAGCombinerInfo &DCI,
558                                 const MipsSubtarget *Subtarget) {
559  // Pattern match EXT.
560  //  $dst = and ((sra or srl) $src , pos), (2**size - 1)
561  //  => ext $dst, $src, size, pos
562  if (DCI.isBeforeLegalizeOps() || !Subtarget->hasMips32r2())
563    return SDValue();
564
565  SDValue ShiftRight = N->getOperand(0), Mask = N->getOperand(1);
566  unsigned ShiftRightOpc = ShiftRight.getOpcode();
567
568  // Op's first operand must be a shift right.
569  if (ShiftRightOpc != ISD::SRA && ShiftRightOpc != ISD::SRL)
570    return SDValue();
571
572  // The second operand of the shift must be an immediate.
573  ConstantSDNode *CN;
574  if (!(CN = dyn_cast<ConstantSDNode>(ShiftRight.getOperand(1))))
575    return SDValue();
576
577  uint64_t Pos = CN->getZExtValue();
578  uint64_t SMPos, SMSize;
579
580  // Op's second operand must be a shifted mask.
581  if (!(CN = dyn_cast<ConstantSDNode>(Mask)) ||
582      !isShiftedMask(CN->getZExtValue(), SMPos, SMSize))
583    return SDValue();
584
585  // Return if the shifted mask does not start at bit 0 or the sum of its size
586  // and Pos exceeds the word's size.
587  EVT ValTy = N->getValueType(0);
588  if (SMPos != 0 || Pos + SMSize > ValTy.getSizeInBits())
589    return SDValue();
590
591  return DAG.getNode(MipsISD::Ext, N->getDebugLoc(), ValTy,
592                     ShiftRight.getOperand(0), DAG.getConstant(Pos, MVT::i32),
593                     DAG.getConstant(SMSize, MVT::i32));
594}
595
596static SDValue performORCombine(SDNode *N, SelectionDAG &DAG,
597                                TargetLowering::DAGCombinerInfo &DCI,
598                                const MipsSubtarget *Subtarget) {
599  // Pattern match INS.
600  //  $dst = or (and $src1 , mask0), (and (shl $src, pos), mask1),
601  //  where mask1 = (2**size - 1) << pos, mask0 = ~mask1
602  //  => ins $dst, $src, size, pos, $src1
603  if (DCI.isBeforeLegalizeOps() || !Subtarget->hasMips32r2())
604    return SDValue();
605
606  SDValue And0 = N->getOperand(0), And1 = N->getOperand(1);
607  uint64_t SMPos0, SMSize0, SMPos1, SMSize1;
608  ConstantSDNode *CN;
609
610  // See if Op's first operand matches (and $src1 , mask0).
611  if (And0.getOpcode() != ISD::AND)
612    return SDValue();
613
614  if (!(CN = dyn_cast<ConstantSDNode>(And0.getOperand(1))) ||
615      !isShiftedMask(~CN->getSExtValue(), SMPos0, SMSize0))
616    return SDValue();
617
618  // See if Op's second operand matches (and (shl $src, pos), mask1).
619  if (And1.getOpcode() != ISD::AND)
620    return SDValue();
621
622  if (!(CN = dyn_cast<ConstantSDNode>(And1.getOperand(1))) ||
623      !isShiftedMask(CN->getZExtValue(), SMPos1, SMSize1))
624    return SDValue();
625
626  // The shift masks must have the same position and size.
627  if (SMPos0 != SMPos1 || SMSize0 != SMSize1)
628    return SDValue();
629
630  SDValue Shl = And1.getOperand(0);
631  if (Shl.getOpcode() != ISD::SHL)
632    return SDValue();
633
634  if (!(CN = dyn_cast<ConstantSDNode>(Shl.getOperand(1))))
635    return SDValue();
636
637  unsigned Shamt = CN->getZExtValue();
638
639  // Return if the shift amount and the first bit position of mask are not the
640  // same.
641  EVT ValTy = N->getValueType(0);
642  if ((Shamt != SMPos0) || (SMPos0 + SMSize0 > ValTy.getSizeInBits()))
643    return SDValue();
644
645  return DAG.getNode(MipsISD::Ins, N->getDebugLoc(), ValTy, Shl.getOperand(0),
646                     DAG.getConstant(SMPos0, MVT::i32),
647                     DAG.getConstant(SMSize0, MVT::i32), And0.getOperand(0));
648}
649
650static SDValue performADDCombine(SDNode *N, SelectionDAG &DAG,
651                                 TargetLowering::DAGCombinerInfo &DCI,
652                                 const MipsSubtarget *Subtarget) {
653  // (add v0, (add v1, abs_lo(tjt))) => (add (add v0, v1), abs_lo(tjt))
654
655  if (DCI.isBeforeLegalizeOps())
656    return SDValue();
657
658  SDValue Add = N->getOperand(1);
659
660  if (Add.getOpcode() != ISD::ADD)
661    return SDValue();
662
663  SDValue Lo = Add.getOperand(1);
664
665  if ((Lo.getOpcode() != MipsISD::Lo) ||
666      (Lo.getOperand(0).getOpcode() != ISD::TargetJumpTable))
667    return SDValue();
668
669  EVT ValTy = N->getValueType(0);
670  DebugLoc DL = N->getDebugLoc();
671
672  SDValue Add1 = DAG.getNode(ISD::ADD, DL, ValTy, N->getOperand(0),
673                             Add.getOperand(0));
674  return DAG.getNode(ISD::ADD, DL, ValTy, Add1, Lo);
675}
676
677SDValue  MipsTargetLowering::PerformDAGCombine(SDNode *N, DAGCombinerInfo &DCI)
678  const {
679  SelectionDAG &DAG = DCI.DAG;
680  unsigned Opc = N->getOpcode();
681
682  switch (Opc) {
683  default: break;
684  case ISD::SDIVREM:
685  case ISD::UDIVREM:
686    return performDivRemCombine(N, DAG, DCI, Subtarget);
687  case ISD::SELECT:
688    return performSELECTCombine(N, DAG, DCI, Subtarget);
689  case ISD::AND:
690    return performANDCombine(N, DAG, DCI, Subtarget);
691  case ISD::OR:
692    return performORCombine(N, DAG, DCI, Subtarget);
693  case ISD::ADD:
694    return performADDCombine(N, DAG, DCI, Subtarget);
695  }
696
697  return SDValue();
698}
699
700void
701MipsTargetLowering::LowerOperationWrapper(SDNode *N,
702                                          SmallVectorImpl<SDValue> &Results,
703                                          SelectionDAG &DAG) const {
704  SDValue Res = LowerOperation(SDValue(N, 0), DAG);
705
706  for (unsigned I = 0, E = Res->getNumValues(); I != E; ++I)
707    Results.push_back(Res.getValue(I));
708}
709
710void
711MipsTargetLowering::ReplaceNodeResults(SDNode *N,
712                                       SmallVectorImpl<SDValue> &Results,
713                                       SelectionDAG &DAG) const {
714  SDValue Res = LowerOperation(SDValue(N, 0), DAG);
715
716  for (unsigned I = 0, E = Res->getNumValues(); I != E; ++I)
717    Results.push_back(Res.getValue(I));
718}
719
720SDValue MipsTargetLowering::
721LowerOperation(SDValue Op, SelectionDAG &DAG) const
722{
723  switch (Op.getOpcode())
724  {
725  case ISD::BR_JT:              return lowerBR_JT(Op, DAG);
726  case ISD::BRCOND:             return lowerBRCOND(Op, DAG);
727  case ISD::ConstantPool:       return lowerConstantPool(Op, DAG);
728  case ISD::GlobalAddress:      return lowerGlobalAddress(Op, DAG);
729  case ISD::BlockAddress:       return lowerBlockAddress(Op, DAG);
730  case ISD::GlobalTLSAddress:   return lowerGlobalTLSAddress(Op, DAG);
731  case ISD::JumpTable:          return lowerJumpTable(Op, DAG);
732  case ISD::SELECT:             return lowerSELECT(Op, DAG);
733  case ISD::SELECT_CC:          return lowerSELECT_CC(Op, DAG);
734  case ISD::SETCC:              return lowerSETCC(Op, DAG);
735  case ISD::VASTART:            return lowerVASTART(Op, DAG);
736  case ISD::FCOPYSIGN:          return lowerFCOPYSIGN(Op, DAG);
737  case ISD::FABS:               return lowerFABS(Op, DAG);
738  case ISD::FRAMEADDR:          return lowerFRAMEADDR(Op, DAG);
739  case ISD::RETURNADDR:         return lowerRETURNADDR(Op, DAG);
740  case ISD::EH_RETURN:          return lowerEH_RETURN(Op, DAG);
741  case ISD::ATOMIC_FENCE:       return lowerATOMIC_FENCE(Op, DAG);
742  case ISD::SHL_PARTS:          return lowerShiftLeftParts(Op, DAG);
743  case ISD::SRA_PARTS:          return lowerShiftRightParts(Op, DAG, true);
744  case ISD::SRL_PARTS:          return lowerShiftRightParts(Op, DAG, false);
745  case ISD::LOAD:               return lowerLOAD(Op, DAG);
746  case ISD::STORE:              return lowerSTORE(Op, DAG);
747  case ISD::ADD:                return lowerADD(Op, DAG);
748  }
749  return SDValue();
750}
751
752//===----------------------------------------------------------------------===//
753//  Lower helper functions
754//===----------------------------------------------------------------------===//
755
756// addLiveIn - This helper function adds the specified physical register to the
757// MachineFunction as a live in value.  It also creates a corresponding
758// virtual register for it.
759static unsigned
760addLiveIn(MachineFunction &MF, unsigned PReg, const TargetRegisterClass *RC)
761{
762  unsigned VReg = MF.getRegInfo().createVirtualRegister(RC);
763  MF.getRegInfo().addLiveIn(PReg, VReg);
764  return VReg;
765}
766
767MachineBasicBlock *
768MipsTargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
769                                                MachineBasicBlock *BB) const {
770  switch (MI->getOpcode()) {
771  default:
772    llvm_unreachable("Unexpected instr type to insert");
773  case Mips::ATOMIC_LOAD_ADD_I8:
774  case Mips::ATOMIC_LOAD_ADD_I8_P8:
775    return emitAtomicBinaryPartword(MI, BB, 1, Mips::ADDu);
776  case Mips::ATOMIC_LOAD_ADD_I16:
777  case Mips::ATOMIC_LOAD_ADD_I16_P8:
778    return emitAtomicBinaryPartword(MI, BB, 2, Mips::ADDu);
779  case Mips::ATOMIC_LOAD_ADD_I32:
780  case Mips::ATOMIC_LOAD_ADD_I32_P8:
781    return emitAtomicBinary(MI, BB, 4, Mips::ADDu);
782  case Mips::ATOMIC_LOAD_ADD_I64:
783  case Mips::ATOMIC_LOAD_ADD_I64_P8:
784    return emitAtomicBinary(MI, BB, 8, Mips::DADDu);
785
786  case Mips::ATOMIC_LOAD_AND_I8:
787  case Mips::ATOMIC_LOAD_AND_I8_P8:
788    return emitAtomicBinaryPartword(MI, BB, 1, Mips::AND);
789  case Mips::ATOMIC_LOAD_AND_I16:
790  case Mips::ATOMIC_LOAD_AND_I16_P8:
791    return emitAtomicBinaryPartword(MI, BB, 2, Mips::AND);
792  case Mips::ATOMIC_LOAD_AND_I32:
793  case Mips::ATOMIC_LOAD_AND_I32_P8:
794    return emitAtomicBinary(MI, BB, 4, Mips::AND);
795  case Mips::ATOMIC_LOAD_AND_I64:
796  case Mips::ATOMIC_LOAD_AND_I64_P8:
797    return emitAtomicBinary(MI, BB, 8, Mips::AND64);
798
799  case Mips::ATOMIC_LOAD_OR_I8:
800  case Mips::ATOMIC_LOAD_OR_I8_P8:
801    return emitAtomicBinaryPartword(MI, BB, 1, Mips::OR);
802  case Mips::ATOMIC_LOAD_OR_I16:
803  case Mips::ATOMIC_LOAD_OR_I16_P8:
804    return emitAtomicBinaryPartword(MI, BB, 2, Mips::OR);
805  case Mips::ATOMIC_LOAD_OR_I32:
806  case Mips::ATOMIC_LOAD_OR_I32_P8:
807    return emitAtomicBinary(MI, BB, 4, Mips::OR);
808  case Mips::ATOMIC_LOAD_OR_I64:
809  case Mips::ATOMIC_LOAD_OR_I64_P8:
810    return emitAtomicBinary(MI, BB, 8, Mips::OR64);
811
812  case Mips::ATOMIC_LOAD_XOR_I8:
813  case Mips::ATOMIC_LOAD_XOR_I8_P8:
814    return emitAtomicBinaryPartword(MI, BB, 1, Mips::XOR);
815  case Mips::ATOMIC_LOAD_XOR_I16:
816  case Mips::ATOMIC_LOAD_XOR_I16_P8:
817    return emitAtomicBinaryPartword(MI, BB, 2, Mips::XOR);
818  case Mips::ATOMIC_LOAD_XOR_I32:
819  case Mips::ATOMIC_LOAD_XOR_I32_P8:
820    return emitAtomicBinary(MI, BB, 4, Mips::XOR);
821  case Mips::ATOMIC_LOAD_XOR_I64:
822  case Mips::ATOMIC_LOAD_XOR_I64_P8:
823    return emitAtomicBinary(MI, BB, 8, Mips::XOR64);
824
825  case Mips::ATOMIC_LOAD_NAND_I8:
826  case Mips::ATOMIC_LOAD_NAND_I8_P8:
827    return emitAtomicBinaryPartword(MI, BB, 1, 0, true);
828  case Mips::ATOMIC_LOAD_NAND_I16:
829  case Mips::ATOMIC_LOAD_NAND_I16_P8:
830    return emitAtomicBinaryPartword(MI, BB, 2, 0, true);
831  case Mips::ATOMIC_LOAD_NAND_I32:
832  case Mips::ATOMIC_LOAD_NAND_I32_P8:
833    return emitAtomicBinary(MI, BB, 4, 0, true);
834  case Mips::ATOMIC_LOAD_NAND_I64:
835  case Mips::ATOMIC_LOAD_NAND_I64_P8:
836    return emitAtomicBinary(MI, BB, 8, 0, true);
837
838  case Mips::ATOMIC_LOAD_SUB_I8:
839  case Mips::ATOMIC_LOAD_SUB_I8_P8:
840    return emitAtomicBinaryPartword(MI, BB, 1, Mips::SUBu);
841  case Mips::ATOMIC_LOAD_SUB_I16:
842  case Mips::ATOMIC_LOAD_SUB_I16_P8:
843    return emitAtomicBinaryPartword(MI, BB, 2, Mips::SUBu);
844  case Mips::ATOMIC_LOAD_SUB_I32:
845  case Mips::ATOMIC_LOAD_SUB_I32_P8:
846    return emitAtomicBinary(MI, BB, 4, Mips::SUBu);
847  case Mips::ATOMIC_LOAD_SUB_I64:
848  case Mips::ATOMIC_LOAD_SUB_I64_P8:
849    return emitAtomicBinary(MI, BB, 8, Mips::DSUBu);
850
851  case Mips::ATOMIC_SWAP_I8:
852  case Mips::ATOMIC_SWAP_I8_P8:
853    return emitAtomicBinaryPartword(MI, BB, 1, 0);
854  case Mips::ATOMIC_SWAP_I16:
855  case Mips::ATOMIC_SWAP_I16_P8:
856    return emitAtomicBinaryPartword(MI, BB, 2, 0);
857  case Mips::ATOMIC_SWAP_I32:
858  case Mips::ATOMIC_SWAP_I32_P8:
859    return emitAtomicBinary(MI, BB, 4, 0);
860  case Mips::ATOMIC_SWAP_I64:
861  case Mips::ATOMIC_SWAP_I64_P8:
862    return emitAtomicBinary(MI, BB, 8, 0);
863
864  case Mips::ATOMIC_CMP_SWAP_I8:
865  case Mips::ATOMIC_CMP_SWAP_I8_P8:
866    return emitAtomicCmpSwapPartword(MI, BB, 1);
867  case Mips::ATOMIC_CMP_SWAP_I16:
868  case Mips::ATOMIC_CMP_SWAP_I16_P8:
869    return emitAtomicCmpSwapPartword(MI, BB, 2);
870  case Mips::ATOMIC_CMP_SWAP_I32:
871  case Mips::ATOMIC_CMP_SWAP_I32_P8:
872    return emitAtomicCmpSwap(MI, BB, 4);
873  case Mips::ATOMIC_CMP_SWAP_I64:
874  case Mips::ATOMIC_CMP_SWAP_I64_P8:
875    return emitAtomicCmpSwap(MI, BB, 8);
876  }
877}
878
879// This function also handles Mips::ATOMIC_SWAP_I32 (when BinOpcode == 0), and
880// Mips::ATOMIC_LOAD_NAND_I32 (when Nand == true)
881MachineBasicBlock *
882MipsTargetLowering::emitAtomicBinary(MachineInstr *MI, MachineBasicBlock *BB,
883                                     unsigned Size, unsigned BinOpcode,
884                                     bool Nand) const {
885  assert((Size == 4 || Size == 8) && "Unsupported size for EmitAtomicBinary.");
886
887  MachineFunction *MF = BB->getParent();
888  MachineRegisterInfo &RegInfo = MF->getRegInfo();
889  const TargetRegisterClass *RC = getRegClassFor(MVT::getIntegerVT(Size * 8));
890  const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
891  DebugLoc DL = MI->getDebugLoc();
892  unsigned LL, SC, AND, NOR, ZERO, BEQ;
893
894  if (Size == 4) {
895    LL = IsN64 ? Mips::LL_P8 : Mips::LL;
896    SC = IsN64 ? Mips::SC_P8 : Mips::SC;
897    AND = Mips::AND;
898    NOR = Mips::NOR;
899    ZERO = Mips::ZERO;
900    BEQ = Mips::BEQ;
901  }
902  else {
903    LL = IsN64 ? Mips::LLD_P8 : Mips::LLD;
904    SC = IsN64 ? Mips::SCD_P8 : Mips::SCD;
905    AND = Mips::AND64;
906    NOR = Mips::NOR64;
907    ZERO = Mips::ZERO_64;
908    BEQ = Mips::BEQ64;
909  }
910
911  unsigned OldVal = MI->getOperand(0).getReg();
912  unsigned Ptr = MI->getOperand(1).getReg();
913  unsigned Incr = MI->getOperand(2).getReg();
914
915  unsigned StoreVal = RegInfo.createVirtualRegister(RC);
916  unsigned AndRes = RegInfo.createVirtualRegister(RC);
917  unsigned Success = RegInfo.createVirtualRegister(RC);
918
919  // insert new blocks after the current block
920  const BasicBlock *LLVM_BB = BB->getBasicBlock();
921  MachineBasicBlock *loopMBB = MF->CreateMachineBasicBlock(LLVM_BB);
922  MachineBasicBlock *exitMBB = MF->CreateMachineBasicBlock(LLVM_BB);
923  MachineFunction::iterator It = BB;
924  ++It;
925  MF->insert(It, loopMBB);
926  MF->insert(It, exitMBB);
927
928  // Transfer the remainder of BB and its successor edges to exitMBB.
929  exitMBB->splice(exitMBB->begin(), BB,
930                  llvm::next(MachineBasicBlock::iterator(MI)),
931                  BB->end());
932  exitMBB->transferSuccessorsAndUpdatePHIs(BB);
933
934  //  thisMBB:
935  //    ...
936  //    fallthrough --> loopMBB
937  BB->addSuccessor(loopMBB);
938  loopMBB->addSuccessor(loopMBB);
939  loopMBB->addSuccessor(exitMBB);
940
941  //  loopMBB:
942  //    ll oldval, 0(ptr)
943  //    <binop> storeval, oldval, incr
944  //    sc success, storeval, 0(ptr)
945  //    beq success, $0, loopMBB
946  BB = loopMBB;
947  BuildMI(BB, DL, TII->get(LL), OldVal).addReg(Ptr).addImm(0);
948  if (Nand) {
949    //  and andres, oldval, incr
950    //  nor storeval, $0, andres
951    BuildMI(BB, DL, TII->get(AND), AndRes).addReg(OldVal).addReg(Incr);
952    BuildMI(BB, DL, TII->get(NOR), StoreVal).addReg(ZERO).addReg(AndRes);
953  } else if (BinOpcode) {
954    //  <binop> storeval, oldval, incr
955    BuildMI(BB, DL, TII->get(BinOpcode), StoreVal).addReg(OldVal).addReg(Incr);
956  } else {
957    StoreVal = Incr;
958  }
959  BuildMI(BB, DL, TII->get(SC), Success).addReg(StoreVal).addReg(Ptr).addImm(0);
960  BuildMI(BB, DL, TII->get(BEQ)).addReg(Success).addReg(ZERO).addMBB(loopMBB);
961
962  MI->eraseFromParent();   // The instruction is gone now.
963
964  return exitMBB;
965}
966
967MachineBasicBlock *
968MipsTargetLowering::emitAtomicBinaryPartword(MachineInstr *MI,
969                                             MachineBasicBlock *BB,
970                                             unsigned Size, unsigned BinOpcode,
971                                             bool Nand) const {
972  assert((Size == 1 || Size == 2) &&
973      "Unsupported size for EmitAtomicBinaryPartial.");
974
975  MachineFunction *MF = BB->getParent();
976  MachineRegisterInfo &RegInfo = MF->getRegInfo();
977  const TargetRegisterClass *RC = getRegClassFor(MVT::i32);
978  const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
979  DebugLoc DL = MI->getDebugLoc();
980  unsigned LL = IsN64 ? Mips::LL_P8 : Mips::LL;
981  unsigned SC = IsN64 ? Mips::SC_P8 : Mips::SC;
982
983  unsigned Dest = MI->getOperand(0).getReg();
984  unsigned Ptr = MI->getOperand(1).getReg();
985  unsigned Incr = MI->getOperand(2).getReg();
986
987  unsigned AlignedAddr = RegInfo.createVirtualRegister(RC);
988  unsigned ShiftAmt = RegInfo.createVirtualRegister(RC);
989  unsigned Mask = RegInfo.createVirtualRegister(RC);
990  unsigned Mask2 = RegInfo.createVirtualRegister(RC);
991  unsigned NewVal = RegInfo.createVirtualRegister(RC);
992  unsigned OldVal = RegInfo.createVirtualRegister(RC);
993  unsigned Incr2 = RegInfo.createVirtualRegister(RC);
994  unsigned MaskLSB2 = RegInfo.createVirtualRegister(RC);
995  unsigned PtrLSB2 = RegInfo.createVirtualRegister(RC);
996  unsigned MaskUpper = RegInfo.createVirtualRegister(RC);
997  unsigned AndRes = RegInfo.createVirtualRegister(RC);
998  unsigned BinOpRes = RegInfo.createVirtualRegister(RC);
999  unsigned MaskedOldVal0 = RegInfo.createVirtualRegister(RC);
1000  unsigned StoreVal = RegInfo.createVirtualRegister(RC);
1001  unsigned MaskedOldVal1 = RegInfo.createVirtualRegister(RC);
1002  unsigned SrlRes = RegInfo.createVirtualRegister(RC);
1003  unsigned SllRes = RegInfo.createVirtualRegister(RC);
1004  unsigned Success = RegInfo.createVirtualRegister(RC);
1005
1006  // insert new blocks after the current block
1007  const BasicBlock *LLVM_BB = BB->getBasicBlock();
1008  MachineBasicBlock *loopMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1009  MachineBasicBlock *sinkMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1010  MachineBasicBlock *exitMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1011  MachineFunction::iterator It = BB;
1012  ++It;
1013  MF->insert(It, loopMBB);
1014  MF->insert(It, sinkMBB);
1015  MF->insert(It, exitMBB);
1016
1017  // Transfer the remainder of BB and its successor edges to exitMBB.
1018  exitMBB->splice(exitMBB->begin(), BB,
1019                  llvm::next(MachineBasicBlock::iterator(MI)), BB->end());
1020  exitMBB->transferSuccessorsAndUpdatePHIs(BB);
1021
1022  BB->addSuccessor(loopMBB);
1023  loopMBB->addSuccessor(loopMBB);
1024  loopMBB->addSuccessor(sinkMBB);
1025  sinkMBB->addSuccessor(exitMBB);
1026
1027  //  thisMBB:
1028  //    addiu   masklsb2,$0,-4                # 0xfffffffc
1029  //    and     alignedaddr,ptr,masklsb2
1030  //    andi    ptrlsb2,ptr,3
1031  //    sll     shiftamt,ptrlsb2,3
1032  //    ori     maskupper,$0,255               # 0xff
1033  //    sll     mask,maskupper,shiftamt
1034  //    nor     mask2,$0,mask
1035  //    sll     incr2,incr,shiftamt
1036
1037  int64_t MaskImm = (Size == 1) ? 255 : 65535;
1038  BuildMI(BB, DL, TII->get(Mips::ADDiu), MaskLSB2)
1039    .addReg(Mips::ZERO).addImm(-4);
1040  BuildMI(BB, DL, TII->get(Mips::AND), AlignedAddr)
1041    .addReg(Ptr).addReg(MaskLSB2);
1042  BuildMI(BB, DL, TII->get(Mips::ANDi), PtrLSB2).addReg(Ptr).addImm(3);
1043  BuildMI(BB, DL, TII->get(Mips::SLL), ShiftAmt).addReg(PtrLSB2).addImm(3);
1044  BuildMI(BB, DL, TII->get(Mips::ORi), MaskUpper)
1045    .addReg(Mips::ZERO).addImm(MaskImm);
1046  BuildMI(BB, DL, TII->get(Mips::SLLV), Mask)
1047    .addReg(ShiftAmt).addReg(MaskUpper);
1048  BuildMI(BB, DL, TII->get(Mips::NOR), Mask2).addReg(Mips::ZERO).addReg(Mask);
1049  BuildMI(BB, DL, TII->get(Mips::SLLV), Incr2).addReg(ShiftAmt).addReg(Incr);
1050
1051  // atomic.load.binop
1052  // loopMBB:
1053  //   ll      oldval,0(alignedaddr)
1054  //   binop   binopres,oldval,incr2
1055  //   and     newval,binopres,mask
1056  //   and     maskedoldval0,oldval,mask2
1057  //   or      storeval,maskedoldval0,newval
1058  //   sc      success,storeval,0(alignedaddr)
1059  //   beq     success,$0,loopMBB
1060
1061  // atomic.swap
1062  // loopMBB:
1063  //   ll      oldval,0(alignedaddr)
1064  //   and     newval,incr2,mask
1065  //   and     maskedoldval0,oldval,mask2
1066  //   or      storeval,maskedoldval0,newval
1067  //   sc      success,storeval,0(alignedaddr)
1068  //   beq     success,$0,loopMBB
1069
1070  BB = loopMBB;
1071  BuildMI(BB, DL, TII->get(LL), OldVal).addReg(AlignedAddr).addImm(0);
1072  if (Nand) {
1073    //  and andres, oldval, incr2
1074    //  nor binopres, $0, andres
1075    //  and newval, binopres, mask
1076    BuildMI(BB, DL, TII->get(Mips::AND), AndRes).addReg(OldVal).addReg(Incr2);
1077    BuildMI(BB, DL, TII->get(Mips::NOR), BinOpRes)
1078      .addReg(Mips::ZERO).addReg(AndRes);
1079    BuildMI(BB, DL, TII->get(Mips::AND), NewVal).addReg(BinOpRes).addReg(Mask);
1080  } else if (BinOpcode) {
1081    //  <binop> binopres, oldval, incr2
1082    //  and newval, binopres, mask
1083    BuildMI(BB, DL, TII->get(BinOpcode), BinOpRes).addReg(OldVal).addReg(Incr2);
1084    BuildMI(BB, DL, TII->get(Mips::AND), NewVal).addReg(BinOpRes).addReg(Mask);
1085  } else {// atomic.swap
1086    //  and newval, incr2, mask
1087    BuildMI(BB, DL, TII->get(Mips::AND), NewVal).addReg(Incr2).addReg(Mask);
1088  }
1089
1090  BuildMI(BB, DL, TII->get(Mips::AND), MaskedOldVal0)
1091    .addReg(OldVal).addReg(Mask2);
1092  BuildMI(BB, DL, TII->get(Mips::OR), StoreVal)
1093    .addReg(MaskedOldVal0).addReg(NewVal);
1094  BuildMI(BB, DL, TII->get(SC), Success)
1095    .addReg(StoreVal).addReg(AlignedAddr).addImm(0);
1096  BuildMI(BB, DL, TII->get(Mips::BEQ))
1097    .addReg(Success).addReg(Mips::ZERO).addMBB(loopMBB);
1098
1099  //  sinkMBB:
1100  //    and     maskedoldval1,oldval,mask
1101  //    srl     srlres,maskedoldval1,shiftamt
1102  //    sll     sllres,srlres,24
1103  //    sra     dest,sllres,24
1104  BB = sinkMBB;
1105  int64_t ShiftImm = (Size == 1) ? 24 : 16;
1106
1107  BuildMI(BB, DL, TII->get(Mips::AND), MaskedOldVal1)
1108    .addReg(OldVal).addReg(Mask);
1109  BuildMI(BB, DL, TII->get(Mips::SRLV), SrlRes)
1110      .addReg(ShiftAmt).addReg(MaskedOldVal1);
1111  BuildMI(BB, DL, TII->get(Mips::SLL), SllRes)
1112      .addReg(SrlRes).addImm(ShiftImm);
1113  BuildMI(BB, DL, TII->get(Mips::SRA), Dest)
1114      .addReg(SllRes).addImm(ShiftImm);
1115
1116  MI->eraseFromParent();   // The instruction is gone now.
1117
1118  return exitMBB;
1119}
1120
1121MachineBasicBlock *
1122MipsTargetLowering::emitAtomicCmpSwap(MachineInstr *MI,
1123                                      MachineBasicBlock *BB,
1124                                      unsigned Size) const {
1125  assert((Size == 4 || Size == 8) && "Unsupported size for EmitAtomicCmpSwap.");
1126
1127  MachineFunction *MF = BB->getParent();
1128  MachineRegisterInfo &RegInfo = MF->getRegInfo();
1129  const TargetRegisterClass *RC = getRegClassFor(MVT::getIntegerVT(Size * 8));
1130  const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
1131  DebugLoc DL = MI->getDebugLoc();
1132  unsigned LL, SC, ZERO, BNE, BEQ;
1133
1134  if (Size == 4) {
1135    LL = IsN64 ? Mips::LL_P8 : Mips::LL;
1136    SC = IsN64 ? Mips::SC_P8 : Mips::SC;
1137    ZERO = Mips::ZERO;
1138    BNE = Mips::BNE;
1139    BEQ = Mips::BEQ;
1140  }
1141  else {
1142    LL = IsN64 ? Mips::LLD_P8 : Mips::LLD;
1143    SC = IsN64 ? Mips::SCD_P8 : Mips::SCD;
1144    ZERO = Mips::ZERO_64;
1145    BNE = Mips::BNE64;
1146    BEQ = Mips::BEQ64;
1147  }
1148
1149  unsigned Dest    = MI->getOperand(0).getReg();
1150  unsigned Ptr     = MI->getOperand(1).getReg();
1151  unsigned OldVal  = MI->getOperand(2).getReg();
1152  unsigned NewVal  = MI->getOperand(3).getReg();
1153
1154  unsigned Success = RegInfo.createVirtualRegister(RC);
1155
1156  // insert new blocks after the current block
1157  const BasicBlock *LLVM_BB = BB->getBasicBlock();
1158  MachineBasicBlock *loop1MBB = MF->CreateMachineBasicBlock(LLVM_BB);
1159  MachineBasicBlock *loop2MBB = MF->CreateMachineBasicBlock(LLVM_BB);
1160  MachineBasicBlock *exitMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1161  MachineFunction::iterator It = BB;
1162  ++It;
1163  MF->insert(It, loop1MBB);
1164  MF->insert(It, loop2MBB);
1165  MF->insert(It, exitMBB);
1166
1167  // Transfer the remainder of BB and its successor edges to exitMBB.
1168  exitMBB->splice(exitMBB->begin(), BB,
1169                  llvm::next(MachineBasicBlock::iterator(MI)), BB->end());
1170  exitMBB->transferSuccessorsAndUpdatePHIs(BB);
1171
1172  //  thisMBB:
1173  //    ...
1174  //    fallthrough --> loop1MBB
1175  BB->addSuccessor(loop1MBB);
1176  loop1MBB->addSuccessor(exitMBB);
1177  loop1MBB->addSuccessor(loop2MBB);
1178  loop2MBB->addSuccessor(loop1MBB);
1179  loop2MBB->addSuccessor(exitMBB);
1180
1181  // loop1MBB:
1182  //   ll dest, 0(ptr)
1183  //   bne dest, oldval, exitMBB
1184  BB = loop1MBB;
1185  BuildMI(BB, DL, TII->get(LL), Dest).addReg(Ptr).addImm(0);
1186  BuildMI(BB, DL, TII->get(BNE))
1187    .addReg(Dest).addReg(OldVal).addMBB(exitMBB);
1188
1189  // loop2MBB:
1190  //   sc success, newval, 0(ptr)
1191  //   beq success, $0, loop1MBB
1192  BB = loop2MBB;
1193  BuildMI(BB, DL, TII->get(SC), Success)
1194    .addReg(NewVal).addReg(Ptr).addImm(0);
1195  BuildMI(BB, DL, TII->get(BEQ))
1196    .addReg(Success).addReg(ZERO).addMBB(loop1MBB);
1197
1198  MI->eraseFromParent();   // The instruction is gone now.
1199
1200  return exitMBB;
1201}
1202
1203MachineBasicBlock *
1204MipsTargetLowering::emitAtomicCmpSwapPartword(MachineInstr *MI,
1205                                              MachineBasicBlock *BB,
1206                                              unsigned Size) const {
1207  assert((Size == 1 || Size == 2) &&
1208      "Unsupported size for EmitAtomicCmpSwapPartial.");
1209
1210  MachineFunction *MF = BB->getParent();
1211  MachineRegisterInfo &RegInfo = MF->getRegInfo();
1212  const TargetRegisterClass *RC = getRegClassFor(MVT::i32);
1213  const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
1214  DebugLoc DL = MI->getDebugLoc();
1215  unsigned LL = IsN64 ? Mips::LL_P8 : Mips::LL;
1216  unsigned SC = IsN64 ? Mips::SC_P8 : Mips::SC;
1217
1218  unsigned Dest    = MI->getOperand(0).getReg();
1219  unsigned Ptr     = MI->getOperand(1).getReg();
1220  unsigned CmpVal  = MI->getOperand(2).getReg();
1221  unsigned NewVal  = MI->getOperand(3).getReg();
1222
1223  unsigned AlignedAddr = RegInfo.createVirtualRegister(RC);
1224  unsigned ShiftAmt = RegInfo.createVirtualRegister(RC);
1225  unsigned Mask = RegInfo.createVirtualRegister(RC);
1226  unsigned Mask2 = RegInfo.createVirtualRegister(RC);
1227  unsigned ShiftedCmpVal = RegInfo.createVirtualRegister(RC);
1228  unsigned OldVal = RegInfo.createVirtualRegister(RC);
1229  unsigned MaskedOldVal0 = RegInfo.createVirtualRegister(RC);
1230  unsigned ShiftedNewVal = RegInfo.createVirtualRegister(RC);
1231  unsigned MaskLSB2 = RegInfo.createVirtualRegister(RC);
1232  unsigned PtrLSB2 = RegInfo.createVirtualRegister(RC);
1233  unsigned MaskUpper = RegInfo.createVirtualRegister(RC);
1234  unsigned MaskedCmpVal = RegInfo.createVirtualRegister(RC);
1235  unsigned MaskedNewVal = RegInfo.createVirtualRegister(RC);
1236  unsigned MaskedOldVal1 = RegInfo.createVirtualRegister(RC);
1237  unsigned StoreVal = RegInfo.createVirtualRegister(RC);
1238  unsigned SrlRes = RegInfo.createVirtualRegister(RC);
1239  unsigned SllRes = RegInfo.createVirtualRegister(RC);
1240  unsigned Success = RegInfo.createVirtualRegister(RC);
1241
1242  // insert new blocks after the current block
1243  const BasicBlock *LLVM_BB = BB->getBasicBlock();
1244  MachineBasicBlock *loop1MBB = MF->CreateMachineBasicBlock(LLVM_BB);
1245  MachineBasicBlock *loop2MBB = MF->CreateMachineBasicBlock(LLVM_BB);
1246  MachineBasicBlock *sinkMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1247  MachineBasicBlock *exitMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1248  MachineFunction::iterator It = BB;
1249  ++It;
1250  MF->insert(It, loop1MBB);
1251  MF->insert(It, loop2MBB);
1252  MF->insert(It, sinkMBB);
1253  MF->insert(It, exitMBB);
1254
1255  // Transfer the remainder of BB and its successor edges to exitMBB.
1256  exitMBB->splice(exitMBB->begin(), BB,
1257                  llvm::next(MachineBasicBlock::iterator(MI)), BB->end());
1258  exitMBB->transferSuccessorsAndUpdatePHIs(BB);
1259
1260  BB->addSuccessor(loop1MBB);
1261  loop1MBB->addSuccessor(sinkMBB);
1262  loop1MBB->addSuccessor(loop2MBB);
1263  loop2MBB->addSuccessor(loop1MBB);
1264  loop2MBB->addSuccessor(sinkMBB);
1265  sinkMBB->addSuccessor(exitMBB);
1266
1267  // FIXME: computation of newval2 can be moved to loop2MBB.
1268  //  thisMBB:
1269  //    addiu   masklsb2,$0,-4                # 0xfffffffc
1270  //    and     alignedaddr,ptr,masklsb2
1271  //    andi    ptrlsb2,ptr,3
1272  //    sll     shiftamt,ptrlsb2,3
1273  //    ori     maskupper,$0,255               # 0xff
1274  //    sll     mask,maskupper,shiftamt
1275  //    nor     mask2,$0,mask
1276  //    andi    maskedcmpval,cmpval,255
1277  //    sll     shiftedcmpval,maskedcmpval,shiftamt
1278  //    andi    maskednewval,newval,255
1279  //    sll     shiftednewval,maskednewval,shiftamt
1280  int64_t MaskImm = (Size == 1) ? 255 : 65535;
1281  BuildMI(BB, DL, TII->get(Mips::ADDiu), MaskLSB2)
1282    .addReg(Mips::ZERO).addImm(-4);
1283  BuildMI(BB, DL, TII->get(Mips::AND), AlignedAddr)
1284    .addReg(Ptr).addReg(MaskLSB2);
1285  BuildMI(BB, DL, TII->get(Mips::ANDi), PtrLSB2).addReg(Ptr).addImm(3);
1286  BuildMI(BB, DL, TII->get(Mips::SLL), ShiftAmt).addReg(PtrLSB2).addImm(3);
1287  BuildMI(BB, DL, TII->get(Mips::ORi), MaskUpper)
1288    .addReg(Mips::ZERO).addImm(MaskImm);
1289  BuildMI(BB, DL, TII->get(Mips::SLLV), Mask)
1290    .addReg(ShiftAmt).addReg(MaskUpper);
1291  BuildMI(BB, DL, TII->get(Mips::NOR), Mask2).addReg(Mips::ZERO).addReg(Mask);
1292  BuildMI(BB, DL, TII->get(Mips::ANDi), MaskedCmpVal)
1293    .addReg(CmpVal).addImm(MaskImm);
1294  BuildMI(BB, DL, TII->get(Mips::SLLV), ShiftedCmpVal)
1295    .addReg(ShiftAmt).addReg(MaskedCmpVal);
1296  BuildMI(BB, DL, TII->get(Mips::ANDi), MaskedNewVal)
1297    .addReg(NewVal).addImm(MaskImm);
1298  BuildMI(BB, DL, TII->get(Mips::SLLV), ShiftedNewVal)
1299    .addReg(ShiftAmt).addReg(MaskedNewVal);
1300
1301  //  loop1MBB:
1302  //    ll      oldval,0(alginedaddr)
1303  //    and     maskedoldval0,oldval,mask
1304  //    bne     maskedoldval0,shiftedcmpval,sinkMBB
1305  BB = loop1MBB;
1306  BuildMI(BB, DL, TII->get(LL), OldVal).addReg(AlignedAddr).addImm(0);
1307  BuildMI(BB, DL, TII->get(Mips::AND), MaskedOldVal0)
1308    .addReg(OldVal).addReg(Mask);
1309  BuildMI(BB, DL, TII->get(Mips::BNE))
1310    .addReg(MaskedOldVal0).addReg(ShiftedCmpVal).addMBB(sinkMBB);
1311
1312  //  loop2MBB:
1313  //    and     maskedoldval1,oldval,mask2
1314  //    or      storeval,maskedoldval1,shiftednewval
1315  //    sc      success,storeval,0(alignedaddr)
1316  //    beq     success,$0,loop1MBB
1317  BB = loop2MBB;
1318  BuildMI(BB, DL, TII->get(Mips::AND), MaskedOldVal1)
1319    .addReg(OldVal).addReg(Mask2);
1320  BuildMI(BB, DL, TII->get(Mips::OR), StoreVal)
1321    .addReg(MaskedOldVal1).addReg(ShiftedNewVal);
1322  BuildMI(BB, DL, TII->get(SC), Success)
1323      .addReg(StoreVal).addReg(AlignedAddr).addImm(0);
1324  BuildMI(BB, DL, TII->get(Mips::BEQ))
1325      .addReg(Success).addReg(Mips::ZERO).addMBB(loop1MBB);
1326
1327  //  sinkMBB:
1328  //    srl     srlres,maskedoldval0,shiftamt
1329  //    sll     sllres,srlres,24
1330  //    sra     dest,sllres,24
1331  BB = sinkMBB;
1332  int64_t ShiftImm = (Size == 1) ? 24 : 16;
1333
1334  BuildMI(BB, DL, TII->get(Mips::SRLV), SrlRes)
1335      .addReg(ShiftAmt).addReg(MaskedOldVal0);
1336  BuildMI(BB, DL, TII->get(Mips::SLL), SllRes)
1337      .addReg(SrlRes).addImm(ShiftImm);
1338  BuildMI(BB, DL, TII->get(Mips::SRA), Dest)
1339      .addReg(SllRes).addImm(ShiftImm);
1340
1341  MI->eraseFromParent();   // The instruction is gone now.
1342
1343  return exitMBB;
1344}
1345
1346//===----------------------------------------------------------------------===//
1347//  Misc Lower Operation implementation
1348//===----------------------------------------------------------------------===//
1349SDValue MipsTargetLowering::lowerBR_JT(SDValue Op, SelectionDAG &DAG) const {
1350  SDValue Chain = Op.getOperand(0);
1351  SDValue Table = Op.getOperand(1);
1352  SDValue Index = Op.getOperand(2);
1353  DebugLoc DL = Op.getDebugLoc();
1354  EVT PTy = getPointerTy();
1355  unsigned EntrySize =
1356    DAG.getMachineFunction().getJumpTableInfo()->getEntrySize(*getDataLayout());
1357
1358  Index = DAG.getNode(ISD::MUL, DL, PTy, Index,
1359                      DAG.getConstant(EntrySize, PTy));
1360  SDValue Addr = DAG.getNode(ISD::ADD, DL, PTy, Index, Table);
1361
1362  EVT MemVT = EVT::getIntegerVT(*DAG.getContext(), EntrySize * 8);
1363  Addr = DAG.getExtLoad(ISD::SEXTLOAD, DL, PTy, Chain, Addr,
1364                        MachinePointerInfo::getJumpTable(), MemVT, false, false,
1365                        0);
1366  Chain = Addr.getValue(1);
1367
1368  if ((getTargetMachine().getRelocationModel() == Reloc::PIC_) || IsN64) {
1369    // For PIC, the sequence is:
1370    // BRIND(load(Jumptable + index) + RelocBase)
1371    // RelocBase can be JumpTable, GOT or some sort of global base.
1372    Addr = DAG.getNode(ISD::ADD, DL, PTy, Addr,
1373                       getPICJumpTableRelocBase(Table, DAG));
1374  }
1375
1376  return DAG.getNode(ISD::BRIND, DL, MVT::Other, Chain, Addr);
1377}
1378
1379SDValue MipsTargetLowering::
1380lowerBRCOND(SDValue Op, SelectionDAG &DAG) const
1381{
1382  // The first operand is the chain, the second is the condition, the third is
1383  // the block to branch to if the condition is true.
1384  SDValue Chain = Op.getOperand(0);
1385  SDValue Dest = Op.getOperand(2);
1386  DebugLoc DL = Op.getDebugLoc();
1387
1388  SDValue CondRes = createFPCmp(DAG, Op.getOperand(1));
1389
1390  // Return if flag is not set by a floating point comparison.
1391  if (CondRes.getOpcode() != MipsISD::FPCmp)
1392    return Op;
1393
1394  SDValue CCNode  = CondRes.getOperand(2);
1395  Mips::CondCode CC =
1396    (Mips::CondCode)cast<ConstantSDNode>(CCNode)->getZExtValue();
1397  unsigned Opc = invertFPCondCodeUser(CC) ? Mips::BRANCH_F : Mips::BRANCH_T;
1398  SDValue BrCode = DAG.getConstant(Opc, MVT::i32);
1399  return DAG.getNode(MipsISD::FPBrcond, DL, Op.getValueType(), Chain, BrCode,
1400                     Dest, CondRes);
1401}
1402
1403SDValue MipsTargetLowering::
1404lowerSELECT(SDValue Op, SelectionDAG &DAG) const
1405{
1406  SDValue Cond = createFPCmp(DAG, Op.getOperand(0));
1407
1408  // Return if flag is not set by a floating point comparison.
1409  if (Cond.getOpcode() != MipsISD::FPCmp)
1410    return Op;
1411
1412  return createCMovFP(DAG, Cond, Op.getOperand(1), Op.getOperand(2),
1413                      Op.getDebugLoc());
1414}
1415
1416SDValue MipsTargetLowering::
1417lowerSELECT_CC(SDValue Op, SelectionDAG &DAG) const
1418{
1419  DebugLoc DL = Op.getDebugLoc();
1420  EVT Ty = Op.getOperand(0).getValueType();
1421  SDValue Cond = DAG.getNode(ISD::SETCC, DL, getSetCCResultType(Ty),
1422                             Op.getOperand(0), Op.getOperand(1),
1423                             Op.getOperand(4));
1424
1425  return DAG.getNode(ISD::SELECT, DL, Op.getValueType(), Cond, Op.getOperand(2),
1426                     Op.getOperand(3));
1427}
1428
1429SDValue MipsTargetLowering::lowerSETCC(SDValue Op, SelectionDAG &DAG) const {
1430  SDValue Cond = createFPCmp(DAG, Op);
1431
1432  assert(Cond.getOpcode() == MipsISD::FPCmp &&
1433         "Floating point operand expected.");
1434
1435  SDValue True  = DAG.getConstant(1, MVT::i32);
1436  SDValue False = DAG.getConstant(0, MVT::i32);
1437
1438  return createCMovFP(DAG, Cond, True, False, Op.getDebugLoc());
1439}
1440
1441SDValue MipsTargetLowering::lowerGlobalAddress(SDValue Op,
1442                                               SelectionDAG &DAG) const {
1443  // FIXME there isn't actually debug info here
1444  DebugLoc DL = Op.getDebugLoc();
1445  const GlobalValue *GV = cast<GlobalAddressSDNode>(Op)->getGlobal();
1446
1447  if (getTargetMachine().getRelocationModel() != Reloc::PIC_ && !IsN64) {
1448    const MipsTargetObjectFile &TLOF =
1449      (const MipsTargetObjectFile&)getObjFileLowering();
1450
1451    // %gp_rel relocation
1452    if (TLOF.IsGlobalInSmallSection(GV, getTargetMachine())) {
1453      SDValue GA = DAG.getTargetGlobalAddress(GV, DL, MVT::i32, 0,
1454                                              MipsII::MO_GPREL);
1455      SDValue GPRelNode = DAG.getNode(MipsISD::GPRel, DL,
1456                                      DAG.getVTList(MVT::i32), &GA, 1);
1457      SDValue GPReg = DAG.getRegister(Mips::GP, MVT::i32);
1458      return DAG.getNode(ISD::ADD, DL, MVT::i32, GPReg, GPRelNode);
1459    }
1460
1461    // %hi/%lo relocation
1462    return getAddrNonPIC(Op, DAG);
1463  }
1464
1465  if (GV->hasInternalLinkage() || (GV->hasLocalLinkage() && !isa<Function>(GV)))
1466    return getAddrLocal(Op, DAG, HasMips64);
1467
1468  if (LargeGOT)
1469    return getAddrGlobalLargeGOT(Op, DAG, MipsII::MO_GOT_HI16,
1470                                 MipsII::MO_GOT_LO16);
1471
1472  return getAddrGlobal(Op, DAG,
1473                       HasMips64 ? MipsII::MO_GOT_DISP : MipsII::MO_GOT16);
1474}
1475
1476SDValue MipsTargetLowering::lowerBlockAddress(SDValue Op,
1477                                              SelectionDAG &DAG) const {
1478  if (getTargetMachine().getRelocationModel() != Reloc::PIC_ && !IsN64)
1479    return getAddrNonPIC(Op, DAG);
1480
1481  return getAddrLocal(Op, DAG, HasMips64);
1482}
1483
1484SDValue MipsTargetLowering::
1485lowerGlobalTLSAddress(SDValue Op, SelectionDAG &DAG) const
1486{
1487  // If the relocation model is PIC, use the General Dynamic TLS Model or
1488  // Local Dynamic TLS model, otherwise use the Initial Exec or
1489  // Local Exec TLS Model.
1490
1491  GlobalAddressSDNode *GA = cast<GlobalAddressSDNode>(Op);
1492  DebugLoc DL = GA->getDebugLoc();
1493  const GlobalValue *GV = GA->getGlobal();
1494  EVT PtrVT = getPointerTy();
1495
1496  TLSModel::Model model = getTargetMachine().getTLSModel(GV);
1497
1498  if (model == TLSModel::GeneralDynamic || model == TLSModel::LocalDynamic) {
1499    // General Dynamic and Local Dynamic TLS Model.
1500    unsigned Flag = (model == TLSModel::LocalDynamic) ? MipsII::MO_TLSLDM
1501                                                      : MipsII::MO_TLSGD;
1502
1503    SDValue TGA = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0, Flag);
1504    SDValue Argument = DAG.getNode(MipsISD::Wrapper, DL, PtrVT,
1505                                   getGlobalReg(DAG, PtrVT), TGA);
1506    unsigned PtrSize = PtrVT.getSizeInBits();
1507    IntegerType *PtrTy = Type::getIntNTy(*DAG.getContext(), PtrSize);
1508
1509    SDValue TlsGetAddr = DAG.getExternalSymbol("__tls_get_addr", PtrVT);
1510
1511    ArgListTy Args;
1512    ArgListEntry Entry;
1513    Entry.Node = Argument;
1514    Entry.Ty = PtrTy;
1515    Args.push_back(Entry);
1516
1517    TargetLowering::CallLoweringInfo CLI(DAG.getEntryNode(), PtrTy,
1518                  false, false, false, false, 0, CallingConv::C,
1519                  /*IsTailCall=*/false, /*doesNotRet=*/false,
1520                  /*isReturnValueUsed=*/true,
1521                  TlsGetAddr, Args, DAG, DL);
1522    std::pair<SDValue, SDValue> CallResult = LowerCallTo(CLI);
1523
1524    SDValue Ret = CallResult.first;
1525
1526    if (model != TLSModel::LocalDynamic)
1527      return Ret;
1528
1529    SDValue TGAHi = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0,
1530                                               MipsII::MO_DTPREL_HI);
1531    SDValue Hi = DAG.getNode(MipsISD::Hi, DL, PtrVT, TGAHi);
1532    SDValue TGALo = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0,
1533                                               MipsII::MO_DTPREL_LO);
1534    SDValue Lo = DAG.getNode(MipsISD::Lo, DL, PtrVT, TGALo);
1535    SDValue Add = DAG.getNode(ISD::ADD, DL, PtrVT, Hi, Ret);
1536    return DAG.getNode(ISD::ADD, DL, PtrVT, Add, Lo);
1537  }
1538
1539  SDValue Offset;
1540  if (model == TLSModel::InitialExec) {
1541    // Initial Exec TLS Model
1542    SDValue TGA = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0,
1543                                             MipsII::MO_GOTTPREL);
1544    TGA = DAG.getNode(MipsISD::Wrapper, DL, PtrVT, getGlobalReg(DAG, PtrVT),
1545                      TGA);
1546    Offset = DAG.getLoad(PtrVT, DL,
1547                         DAG.getEntryNode(), TGA, MachinePointerInfo(),
1548                         false, false, false, 0);
1549  } else {
1550    // Local Exec TLS Model
1551    assert(model == TLSModel::LocalExec);
1552    SDValue TGAHi = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0,
1553                                               MipsII::MO_TPREL_HI);
1554    SDValue TGALo = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0,
1555                                               MipsII::MO_TPREL_LO);
1556    SDValue Hi = DAG.getNode(MipsISD::Hi, DL, PtrVT, TGAHi);
1557    SDValue Lo = DAG.getNode(MipsISD::Lo, DL, PtrVT, TGALo);
1558    Offset = DAG.getNode(ISD::ADD, DL, PtrVT, Hi, Lo);
1559  }
1560
1561  SDValue ThreadPointer = DAG.getNode(MipsISD::ThreadPointer, DL, PtrVT);
1562  return DAG.getNode(ISD::ADD, DL, PtrVT, ThreadPointer, Offset);
1563}
1564
1565SDValue MipsTargetLowering::
1566lowerJumpTable(SDValue Op, SelectionDAG &DAG) const
1567{
1568  if (getTargetMachine().getRelocationModel() != Reloc::PIC_ && !IsN64)
1569    return getAddrNonPIC(Op, DAG);
1570
1571  return getAddrLocal(Op, DAG, HasMips64);
1572}
1573
1574SDValue MipsTargetLowering::
1575lowerConstantPool(SDValue Op, SelectionDAG &DAG) const
1576{
1577  // gp_rel relocation
1578  // FIXME: we should reference the constant pool using small data sections,
1579  // but the asm printer currently doesn't support this feature without
1580  // hacking it. This feature should come soon so we can uncomment the
1581  // stuff below.
1582  //if (IsInSmallSection(C->getType())) {
1583  //  SDValue GPRelNode = DAG.getNode(MipsISD::GPRel, MVT::i32, CP);
1584  //  SDValue GOT = DAG.getGLOBAL_OFFSET_TABLE(MVT::i32);
1585  //  ResNode = DAG.getNode(ISD::ADD, MVT::i32, GOT, GPRelNode);
1586
1587  if (getTargetMachine().getRelocationModel() != Reloc::PIC_ && !IsN64)
1588    return getAddrNonPIC(Op, DAG);
1589
1590  return getAddrLocal(Op, DAG, HasMips64);
1591}
1592
1593SDValue MipsTargetLowering::lowerVASTART(SDValue Op, SelectionDAG &DAG) const {
1594  MachineFunction &MF = DAG.getMachineFunction();
1595  MipsFunctionInfo *FuncInfo = MF.getInfo<MipsFunctionInfo>();
1596
1597  DebugLoc DL = Op.getDebugLoc();
1598  SDValue FI = DAG.getFrameIndex(FuncInfo->getVarArgsFrameIndex(),
1599                                 getPointerTy());
1600
1601  // vastart just stores the address of the VarArgsFrameIndex slot into the
1602  // memory location argument.
1603  const Value *SV = cast<SrcValueSDNode>(Op.getOperand(2))->getValue();
1604  return DAG.getStore(Op.getOperand(0), DL, FI, Op.getOperand(1),
1605                      MachinePointerInfo(SV), false, false, 0);
1606}
1607
1608static SDValue lowerFCOPYSIGN32(SDValue Op, SelectionDAG &DAG, bool HasR2) {
1609  EVT TyX = Op.getOperand(0).getValueType();
1610  EVT TyY = Op.getOperand(1).getValueType();
1611  SDValue Const1 = DAG.getConstant(1, MVT::i32);
1612  SDValue Const31 = DAG.getConstant(31, MVT::i32);
1613  DebugLoc DL = Op.getDebugLoc();
1614  SDValue Res;
1615
1616  // If operand is of type f64, extract the upper 32-bit. Otherwise, bitcast it
1617  // to i32.
1618  SDValue X = (TyX == MVT::f32) ?
1619    DAG.getNode(ISD::BITCAST, DL, MVT::i32, Op.getOperand(0)) :
1620    DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32, Op.getOperand(0),
1621                Const1);
1622  SDValue Y = (TyY == MVT::f32) ?
1623    DAG.getNode(ISD::BITCAST, DL, MVT::i32, Op.getOperand(1)) :
1624    DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32, Op.getOperand(1),
1625                Const1);
1626
1627  if (HasR2) {
1628    // ext  E, Y, 31, 1  ; extract bit31 of Y
1629    // ins  X, E, 31, 1  ; insert extracted bit at bit31 of X
1630    SDValue E = DAG.getNode(MipsISD::Ext, DL, MVT::i32, Y, Const31, Const1);
1631    Res = DAG.getNode(MipsISD::Ins, DL, MVT::i32, E, Const31, Const1, X);
1632  } else {
1633    // sll SllX, X, 1
1634    // srl SrlX, SllX, 1
1635    // srl SrlY, Y, 31
1636    // sll SllY, SrlX, 31
1637    // or  Or, SrlX, SllY
1638    SDValue SllX = DAG.getNode(ISD::SHL, DL, MVT::i32, X, Const1);
1639    SDValue SrlX = DAG.getNode(ISD::SRL, DL, MVT::i32, SllX, Const1);
1640    SDValue SrlY = DAG.getNode(ISD::SRL, DL, MVT::i32, Y, Const31);
1641    SDValue SllY = DAG.getNode(ISD::SHL, DL, MVT::i32, SrlY, Const31);
1642    Res = DAG.getNode(ISD::OR, DL, MVT::i32, SrlX, SllY);
1643  }
1644
1645  if (TyX == MVT::f32)
1646    return DAG.getNode(ISD::BITCAST, DL, Op.getOperand(0).getValueType(), Res);
1647
1648  SDValue LowX = DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32,
1649                             Op.getOperand(0), DAG.getConstant(0, MVT::i32));
1650  return DAG.getNode(MipsISD::BuildPairF64, DL, MVT::f64, LowX, Res);
1651}
1652
1653static SDValue lowerFCOPYSIGN64(SDValue Op, SelectionDAG &DAG, bool HasR2) {
1654  unsigned WidthX = Op.getOperand(0).getValueSizeInBits();
1655  unsigned WidthY = Op.getOperand(1).getValueSizeInBits();
1656  EVT TyX = MVT::getIntegerVT(WidthX), TyY = MVT::getIntegerVT(WidthY);
1657  SDValue Const1 = DAG.getConstant(1, MVT::i32);
1658  DebugLoc DL = Op.getDebugLoc();
1659
1660  // Bitcast to integer nodes.
1661  SDValue X = DAG.getNode(ISD::BITCAST, DL, TyX, Op.getOperand(0));
1662  SDValue Y = DAG.getNode(ISD::BITCAST, DL, TyY, Op.getOperand(1));
1663
1664  if (HasR2) {
1665    // ext  E, Y, width(Y) - 1, 1  ; extract bit width(Y)-1 of Y
1666    // ins  X, E, width(X) - 1, 1  ; insert extracted bit at bit width(X)-1 of X
1667    SDValue E = DAG.getNode(MipsISD::Ext, DL, TyY, Y,
1668                            DAG.getConstant(WidthY - 1, MVT::i32), Const1);
1669
1670    if (WidthX > WidthY)
1671      E = DAG.getNode(ISD::ZERO_EXTEND, DL, TyX, E);
1672    else if (WidthY > WidthX)
1673      E = DAG.getNode(ISD::TRUNCATE, DL, TyX, E);
1674
1675    SDValue I = DAG.getNode(MipsISD::Ins, DL, TyX, E,
1676                            DAG.getConstant(WidthX - 1, MVT::i32), Const1, X);
1677    return DAG.getNode(ISD::BITCAST, DL, Op.getOperand(0).getValueType(), I);
1678  }
1679
1680  // (d)sll SllX, X, 1
1681  // (d)srl SrlX, SllX, 1
1682  // (d)srl SrlY, Y, width(Y)-1
1683  // (d)sll SllY, SrlX, width(Y)-1
1684  // or     Or, SrlX, SllY
1685  SDValue SllX = DAG.getNode(ISD::SHL, DL, TyX, X, Const1);
1686  SDValue SrlX = DAG.getNode(ISD::SRL, DL, TyX, SllX, Const1);
1687  SDValue SrlY = DAG.getNode(ISD::SRL, DL, TyY, Y,
1688                             DAG.getConstant(WidthY - 1, MVT::i32));
1689
1690  if (WidthX > WidthY)
1691    SrlY = DAG.getNode(ISD::ZERO_EXTEND, DL, TyX, SrlY);
1692  else if (WidthY > WidthX)
1693    SrlY = DAG.getNode(ISD::TRUNCATE, DL, TyX, SrlY);
1694
1695  SDValue SllY = DAG.getNode(ISD::SHL, DL, TyX, SrlY,
1696                             DAG.getConstant(WidthX - 1, MVT::i32));
1697  SDValue Or = DAG.getNode(ISD::OR, DL, TyX, SrlX, SllY);
1698  return DAG.getNode(ISD::BITCAST, DL, Op.getOperand(0).getValueType(), Or);
1699}
1700
1701SDValue
1702MipsTargetLowering::lowerFCOPYSIGN(SDValue Op, SelectionDAG &DAG) const {
1703  if (Subtarget->hasMips64())
1704    return lowerFCOPYSIGN64(Op, DAG, Subtarget->hasMips32r2());
1705
1706  return lowerFCOPYSIGN32(Op, DAG, Subtarget->hasMips32r2());
1707}
1708
1709static SDValue lowerFABS32(SDValue Op, SelectionDAG &DAG, bool HasR2) {
1710  SDValue Res, Const1 = DAG.getConstant(1, MVT::i32);
1711  DebugLoc DL = Op.getDebugLoc();
1712
1713  // If operand is of type f64, extract the upper 32-bit. Otherwise, bitcast it
1714  // to i32.
1715  SDValue X = (Op.getValueType() == MVT::f32) ?
1716    DAG.getNode(ISD::BITCAST, DL, MVT::i32, Op.getOperand(0)) :
1717    DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32, Op.getOperand(0),
1718                Const1);
1719
1720  // Clear MSB.
1721  if (HasR2)
1722    Res = DAG.getNode(MipsISD::Ins, DL, MVT::i32,
1723                      DAG.getRegister(Mips::ZERO, MVT::i32),
1724                      DAG.getConstant(31, MVT::i32), Const1, X);
1725  else {
1726    SDValue SllX = DAG.getNode(ISD::SHL, DL, MVT::i32, X, Const1);
1727    Res = DAG.getNode(ISD::SRL, DL, MVT::i32, SllX, Const1);
1728  }
1729
1730  if (Op.getValueType() == MVT::f32)
1731    return DAG.getNode(ISD::BITCAST, DL, MVT::f32, Res);
1732
1733  SDValue LowX = DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32,
1734                             Op.getOperand(0), DAG.getConstant(0, MVT::i32));
1735  return DAG.getNode(MipsISD::BuildPairF64, DL, MVT::f64, LowX, Res);
1736}
1737
1738static SDValue lowerFABS64(SDValue Op, SelectionDAG &DAG, bool HasR2) {
1739  SDValue Res, Const1 = DAG.getConstant(1, MVT::i32);
1740  DebugLoc DL = Op.getDebugLoc();
1741
1742  // Bitcast to integer node.
1743  SDValue X = DAG.getNode(ISD::BITCAST, DL, MVT::i64, Op.getOperand(0));
1744
1745  // Clear MSB.
1746  if (HasR2)
1747    Res = DAG.getNode(MipsISD::Ins, DL, MVT::i64,
1748                      DAG.getRegister(Mips::ZERO_64, MVT::i64),
1749                      DAG.getConstant(63, MVT::i32), Const1, X);
1750  else {
1751    SDValue SllX = DAG.getNode(ISD::SHL, DL, MVT::i64, X, Const1);
1752    Res = DAG.getNode(ISD::SRL, DL, MVT::i64, SllX, Const1);
1753  }
1754
1755  return DAG.getNode(ISD::BITCAST, DL, MVT::f64, Res);
1756}
1757
1758SDValue
1759MipsTargetLowering::lowerFABS(SDValue Op, SelectionDAG &DAG) const {
1760  if (Subtarget->hasMips64() && (Op.getValueType() == MVT::f64))
1761    return lowerFABS64(Op, DAG, Subtarget->hasMips32r2());
1762
1763  return lowerFABS32(Op, DAG, Subtarget->hasMips32r2());
1764}
1765
1766SDValue MipsTargetLowering::
1767lowerFRAMEADDR(SDValue Op, SelectionDAG &DAG) const {
1768  // check the depth
1769  assert((cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue() == 0) &&
1770         "Frame address can only be determined for current frame.");
1771
1772  MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo();
1773  MFI->setFrameAddressIsTaken(true);
1774  EVT VT = Op.getValueType();
1775  DebugLoc DL = Op.getDebugLoc();
1776  SDValue FrameAddr = DAG.getCopyFromReg(DAG.getEntryNode(), DL,
1777                                         IsN64 ? Mips::FP_64 : Mips::FP, VT);
1778  return FrameAddr;
1779}
1780
1781SDValue MipsTargetLowering::lowerRETURNADDR(SDValue Op,
1782                                            SelectionDAG &DAG) const {
1783  // check the depth
1784  assert((cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue() == 0) &&
1785         "Return address can be determined only for current frame.");
1786
1787  MachineFunction &MF = DAG.getMachineFunction();
1788  MachineFrameInfo *MFI = MF.getFrameInfo();
1789  MVT VT = Op.getSimpleValueType();
1790  unsigned RA = IsN64 ? Mips::RA_64 : Mips::RA;
1791  MFI->setReturnAddressIsTaken(true);
1792
1793  // Return RA, which contains the return address. Mark it an implicit live-in.
1794  unsigned Reg = MF.addLiveIn(RA, getRegClassFor(VT));
1795  return DAG.getCopyFromReg(DAG.getEntryNode(), Op.getDebugLoc(), Reg, VT);
1796}
1797
1798// An EH_RETURN is the result of lowering llvm.eh.return which in turn is
1799// generated from __builtin_eh_return (offset, handler)
1800// The effect of this is to adjust the stack pointer by "offset"
1801// and then branch to "handler".
1802SDValue MipsTargetLowering::lowerEH_RETURN(SDValue Op, SelectionDAG &DAG)
1803                                                                     const {
1804  MachineFunction &MF = DAG.getMachineFunction();
1805  MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
1806
1807  MipsFI->setCallsEhReturn();
1808  SDValue Chain     = Op.getOperand(0);
1809  SDValue Offset    = Op.getOperand(1);
1810  SDValue Handler   = Op.getOperand(2);
1811  DebugLoc DL       = Op.getDebugLoc();
1812  EVT Ty = IsN64 ? MVT::i64 : MVT::i32;
1813
1814  // Store stack offset in V1, store jump target in V0. Glue CopyToReg and
1815  // EH_RETURN nodes, so that instructions are emitted back-to-back.
1816  unsigned OffsetReg = IsN64 ? Mips::V1_64 : Mips::V1;
1817  unsigned AddrReg = IsN64 ? Mips::V0_64 : Mips::V0;
1818  Chain = DAG.getCopyToReg(Chain, DL, OffsetReg, Offset, SDValue());
1819  Chain = DAG.getCopyToReg(Chain, DL, AddrReg, Handler, Chain.getValue(1));
1820  return DAG.getNode(MipsISD::EH_RETURN, DL, MVT::Other, Chain,
1821                     DAG.getRegister(OffsetReg, Ty),
1822                     DAG.getRegister(AddrReg, getPointerTy()),
1823                     Chain.getValue(1));
1824}
1825
1826SDValue MipsTargetLowering::lowerATOMIC_FENCE(SDValue Op,
1827                                              SelectionDAG &DAG) const {
1828  // FIXME: Need pseudo-fence for 'singlethread' fences
1829  // FIXME: Set SType for weaker fences where supported/appropriate.
1830  unsigned SType = 0;
1831  DebugLoc DL = Op.getDebugLoc();
1832  return DAG.getNode(MipsISD::Sync, DL, MVT::Other, Op.getOperand(0),
1833                     DAG.getConstant(SType, MVT::i32));
1834}
1835
1836SDValue MipsTargetLowering::lowerShiftLeftParts(SDValue Op,
1837                                                SelectionDAG &DAG) const {
1838  DebugLoc DL = Op.getDebugLoc();
1839  SDValue Lo = Op.getOperand(0), Hi = Op.getOperand(1);
1840  SDValue Shamt = Op.getOperand(2);
1841
1842  // if shamt < 32:
1843  //  lo = (shl lo, shamt)
1844  //  hi = (or (shl hi, shamt) (srl (srl lo, 1), ~shamt))
1845  // else:
1846  //  lo = 0
1847  //  hi = (shl lo, shamt[4:0])
1848  SDValue Not = DAG.getNode(ISD::XOR, DL, MVT::i32, Shamt,
1849                            DAG.getConstant(-1, MVT::i32));
1850  SDValue ShiftRight1Lo = DAG.getNode(ISD::SRL, DL, MVT::i32, Lo,
1851                                      DAG.getConstant(1, MVT::i32));
1852  SDValue ShiftRightLo = DAG.getNode(ISD::SRL, DL, MVT::i32, ShiftRight1Lo,
1853                                     Not);
1854  SDValue ShiftLeftHi = DAG.getNode(ISD::SHL, DL, MVT::i32, Hi, Shamt);
1855  SDValue Or = DAG.getNode(ISD::OR, DL, MVT::i32, ShiftLeftHi, ShiftRightLo);
1856  SDValue ShiftLeftLo = DAG.getNode(ISD::SHL, DL, MVT::i32, Lo, Shamt);
1857  SDValue Cond = DAG.getNode(ISD::AND, DL, MVT::i32, Shamt,
1858                             DAG.getConstant(0x20, MVT::i32));
1859  Lo = DAG.getNode(ISD::SELECT, DL, MVT::i32, Cond,
1860                   DAG.getConstant(0, MVT::i32), ShiftLeftLo);
1861  Hi = DAG.getNode(ISD::SELECT, DL, MVT::i32, Cond, ShiftLeftLo, Or);
1862
1863  SDValue Ops[2] = {Lo, Hi};
1864  return DAG.getMergeValues(Ops, 2, DL);
1865}
1866
1867SDValue MipsTargetLowering::lowerShiftRightParts(SDValue Op, SelectionDAG &DAG,
1868                                                 bool IsSRA) const {
1869  DebugLoc DL = Op.getDebugLoc();
1870  SDValue Lo = Op.getOperand(0), Hi = Op.getOperand(1);
1871  SDValue Shamt = Op.getOperand(2);
1872
1873  // if shamt < 32:
1874  //  lo = (or (shl (shl hi, 1), ~shamt) (srl lo, shamt))
1875  //  if isSRA:
1876  //    hi = (sra hi, shamt)
1877  //  else:
1878  //    hi = (srl hi, shamt)
1879  // else:
1880  //  if isSRA:
1881  //   lo = (sra hi, shamt[4:0])
1882  //   hi = (sra hi, 31)
1883  //  else:
1884  //   lo = (srl hi, shamt[4:0])
1885  //   hi = 0
1886  SDValue Not = DAG.getNode(ISD::XOR, DL, MVT::i32, Shamt,
1887                            DAG.getConstant(-1, MVT::i32));
1888  SDValue ShiftLeft1Hi = DAG.getNode(ISD::SHL, DL, MVT::i32, Hi,
1889                                     DAG.getConstant(1, MVT::i32));
1890  SDValue ShiftLeftHi = DAG.getNode(ISD::SHL, DL, MVT::i32, ShiftLeft1Hi, Not);
1891  SDValue ShiftRightLo = DAG.getNode(ISD::SRL, DL, MVT::i32, Lo, Shamt);
1892  SDValue Or = DAG.getNode(ISD::OR, DL, MVT::i32, ShiftLeftHi, ShiftRightLo);
1893  SDValue ShiftRightHi = DAG.getNode(IsSRA ? ISD::SRA : ISD::SRL, DL, MVT::i32,
1894                                     Hi, Shamt);
1895  SDValue Cond = DAG.getNode(ISD::AND, DL, MVT::i32, Shamt,
1896                             DAG.getConstant(0x20, MVT::i32));
1897  SDValue Shift31 = DAG.getNode(ISD::SRA, DL, MVT::i32, Hi,
1898                                DAG.getConstant(31, MVT::i32));
1899  Lo = DAG.getNode(ISD::SELECT, DL, MVT::i32, Cond, ShiftRightHi, Or);
1900  Hi = DAG.getNode(ISD::SELECT, DL, MVT::i32, Cond,
1901                   IsSRA ? Shift31 : DAG.getConstant(0, MVT::i32),
1902                   ShiftRightHi);
1903
1904  SDValue Ops[2] = {Lo, Hi};
1905  return DAG.getMergeValues(Ops, 2, DL);
1906}
1907
1908static SDValue createLoadLR(unsigned Opc, SelectionDAG &DAG, LoadSDNode *LD,
1909                            SDValue Chain, SDValue Src, unsigned Offset) {
1910  SDValue Ptr = LD->getBasePtr();
1911  EVT VT = LD->getValueType(0), MemVT = LD->getMemoryVT();
1912  EVT BasePtrVT = Ptr.getValueType();
1913  DebugLoc DL = LD->getDebugLoc();
1914  SDVTList VTList = DAG.getVTList(VT, MVT::Other);
1915
1916  if (Offset)
1917    Ptr = DAG.getNode(ISD::ADD, DL, BasePtrVT, Ptr,
1918                      DAG.getConstant(Offset, BasePtrVT));
1919
1920  SDValue Ops[] = { Chain, Ptr, Src };
1921  return DAG.getMemIntrinsicNode(Opc, DL, VTList, Ops, 3, MemVT,
1922                                 LD->getMemOperand());
1923}
1924
1925// Expand an unaligned 32 or 64-bit integer load node.
1926SDValue MipsTargetLowering::lowerLOAD(SDValue Op, SelectionDAG &DAG) const {
1927  LoadSDNode *LD = cast<LoadSDNode>(Op);
1928  EVT MemVT = LD->getMemoryVT();
1929
1930  // Return if load is aligned or if MemVT is neither i32 nor i64.
1931  if ((LD->getAlignment() >= MemVT.getSizeInBits() / 8) ||
1932      ((MemVT != MVT::i32) && (MemVT != MVT::i64)))
1933    return SDValue();
1934
1935  bool IsLittle = Subtarget->isLittle();
1936  EVT VT = Op.getValueType();
1937  ISD::LoadExtType ExtType = LD->getExtensionType();
1938  SDValue Chain = LD->getChain(), Undef = DAG.getUNDEF(VT);
1939
1940  assert((VT == MVT::i32) || (VT == MVT::i64));
1941
1942  // Expand
1943  //  (set dst, (i64 (load baseptr)))
1944  // to
1945  //  (set tmp, (ldl (add baseptr, 7), undef))
1946  //  (set dst, (ldr baseptr, tmp))
1947  if ((VT == MVT::i64) && (ExtType == ISD::NON_EXTLOAD)) {
1948    SDValue LDL = createLoadLR(MipsISD::LDL, DAG, LD, Chain, Undef,
1949                               IsLittle ? 7 : 0);
1950    return createLoadLR(MipsISD::LDR, DAG, LD, LDL.getValue(1), LDL,
1951                        IsLittle ? 0 : 7);
1952  }
1953
1954  SDValue LWL = createLoadLR(MipsISD::LWL, DAG, LD, Chain, Undef,
1955                             IsLittle ? 3 : 0);
1956  SDValue LWR = createLoadLR(MipsISD::LWR, DAG, LD, LWL.getValue(1), LWL,
1957                             IsLittle ? 0 : 3);
1958
1959  // Expand
1960  //  (set dst, (i32 (load baseptr))) or
1961  //  (set dst, (i64 (sextload baseptr))) or
1962  //  (set dst, (i64 (extload baseptr)))
1963  // to
1964  //  (set tmp, (lwl (add baseptr, 3), undef))
1965  //  (set dst, (lwr baseptr, tmp))
1966  if ((VT == MVT::i32) || (ExtType == ISD::SEXTLOAD) ||
1967      (ExtType == ISD::EXTLOAD))
1968    return LWR;
1969
1970  assert((VT == MVT::i64) && (ExtType == ISD::ZEXTLOAD));
1971
1972  // Expand
1973  //  (set dst, (i64 (zextload baseptr)))
1974  // to
1975  //  (set tmp0, (lwl (add baseptr, 3), undef))
1976  //  (set tmp1, (lwr baseptr, tmp0))
1977  //  (set tmp2, (shl tmp1, 32))
1978  //  (set dst, (srl tmp2, 32))
1979  DebugLoc DL = LD->getDebugLoc();
1980  SDValue Const32 = DAG.getConstant(32, MVT::i32);
1981  SDValue SLL = DAG.getNode(ISD::SHL, DL, MVT::i64, LWR, Const32);
1982  SDValue SRL = DAG.getNode(ISD::SRL, DL, MVT::i64, SLL, Const32);
1983  SDValue Ops[] = { SRL, LWR.getValue(1) };
1984  return DAG.getMergeValues(Ops, 2, DL);
1985}
1986
1987static SDValue createStoreLR(unsigned Opc, SelectionDAG &DAG, StoreSDNode *SD,
1988                             SDValue Chain, unsigned Offset) {
1989  SDValue Ptr = SD->getBasePtr(), Value = SD->getValue();
1990  EVT MemVT = SD->getMemoryVT(), BasePtrVT = Ptr.getValueType();
1991  DebugLoc DL = SD->getDebugLoc();
1992  SDVTList VTList = DAG.getVTList(MVT::Other);
1993
1994  if (Offset)
1995    Ptr = DAG.getNode(ISD::ADD, DL, BasePtrVT, Ptr,
1996                      DAG.getConstant(Offset, BasePtrVT));
1997
1998  SDValue Ops[] = { Chain, Value, Ptr };
1999  return DAG.getMemIntrinsicNode(Opc, DL, VTList, Ops, 3, MemVT,
2000                                 SD->getMemOperand());
2001}
2002
2003// Expand an unaligned 32 or 64-bit integer store node.
2004SDValue MipsTargetLowering::lowerSTORE(SDValue Op, SelectionDAG &DAG) const {
2005  StoreSDNode *SD = cast<StoreSDNode>(Op);
2006  EVT MemVT = SD->getMemoryVT();
2007
2008  // Return if store is aligned or if MemVT is neither i32 nor i64.
2009  if ((SD->getAlignment() >= MemVT.getSizeInBits() / 8) ||
2010      ((MemVT != MVT::i32) && (MemVT != MVT::i64)))
2011    return SDValue();
2012
2013  bool IsLittle = Subtarget->isLittle();
2014  SDValue Value = SD->getValue(), Chain = SD->getChain();
2015  EVT VT = Value.getValueType();
2016
2017  // Expand
2018  //  (store val, baseptr) or
2019  //  (truncstore val, baseptr)
2020  // to
2021  //  (swl val, (add baseptr, 3))
2022  //  (swr val, baseptr)
2023  if ((VT == MVT::i32) || SD->isTruncatingStore()) {
2024    SDValue SWL = createStoreLR(MipsISD::SWL, DAG, SD, Chain,
2025                                IsLittle ? 3 : 0);
2026    return createStoreLR(MipsISD::SWR, DAG, SD, SWL, IsLittle ? 0 : 3);
2027  }
2028
2029  assert(VT == MVT::i64);
2030
2031  // Expand
2032  //  (store val, baseptr)
2033  // to
2034  //  (sdl val, (add baseptr, 7))
2035  //  (sdr val, baseptr)
2036  SDValue SDL = createStoreLR(MipsISD::SDL, DAG, SD, Chain, IsLittle ? 7 : 0);
2037  return createStoreLR(MipsISD::SDR, DAG, SD, SDL, IsLittle ? 0 : 7);
2038}
2039
2040SDValue MipsTargetLowering::lowerADD(SDValue Op, SelectionDAG &DAG) const {
2041  if (Op->getOperand(0).getOpcode() != ISD::FRAMEADDR
2042      || cast<ConstantSDNode>
2043        (Op->getOperand(0).getOperand(0))->getZExtValue() != 0
2044      || Op->getOperand(1).getOpcode() != ISD::FRAME_TO_ARGS_OFFSET)
2045    return SDValue();
2046
2047  // The pattern
2048  //   (add (frameaddr 0), (frame_to_args_offset))
2049  // results from lowering llvm.eh.dwarf.cfa intrinsic. Transform it to
2050  //   (add FrameObject, 0)
2051  // where FrameObject is a fixed StackObject with offset 0 which points to
2052  // the old stack pointer.
2053  MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo();
2054  EVT ValTy = Op->getValueType(0);
2055  int FI = MFI->CreateFixedObject(Op.getValueSizeInBits() / 8, 0, false);
2056  SDValue InArgsAddr = DAG.getFrameIndex(FI, ValTy);
2057  return DAG.getNode(ISD::ADD, Op->getDebugLoc(), ValTy, InArgsAddr,
2058                     DAG.getConstant(0, ValTy));
2059}
2060
2061//===----------------------------------------------------------------------===//
2062//                      Calling Convention Implementation
2063//===----------------------------------------------------------------------===//
2064
2065//===----------------------------------------------------------------------===//
2066// TODO: Implement a generic logic using tblgen that can support this.
2067// Mips O32 ABI rules:
2068// ---
2069// i32 - Passed in A0, A1, A2, A3 and stack
2070// f32 - Only passed in f32 registers if no int reg has been used yet to hold
2071//       an argument. Otherwise, passed in A1, A2, A3 and stack.
2072// f64 - Only passed in two aliased f32 registers if no int reg has been used
2073//       yet to hold an argument. Otherwise, use A2, A3 and stack. If A1 is
2074//       not used, it must be shadowed. If only A3 is avaiable, shadow it and
2075//       go to stack.
2076//
2077//  For vararg functions, all arguments are passed in A0, A1, A2, A3 and stack.
2078//===----------------------------------------------------------------------===//
2079
2080static bool CC_MipsO32(unsigned ValNo, MVT ValVT,
2081                       MVT LocVT, CCValAssign::LocInfo LocInfo,
2082                       ISD::ArgFlagsTy ArgFlags, CCState &State) {
2083
2084  static const unsigned IntRegsSize=4, FloatRegsSize=2;
2085
2086  static const uint16_t IntRegs[] = {
2087      Mips::A0, Mips::A1, Mips::A2, Mips::A3
2088  };
2089  static const uint16_t F32Regs[] = {
2090      Mips::F12, Mips::F14
2091  };
2092  static const uint16_t F64Regs[] = {
2093      Mips::D6, Mips::D7
2094  };
2095
2096  // Do not process byval args here.
2097  if (ArgFlags.isByVal())
2098    return true;
2099
2100  // Promote i8 and i16
2101  if (LocVT == MVT::i8 || LocVT == MVT::i16) {
2102    LocVT = MVT::i32;
2103    if (ArgFlags.isSExt())
2104      LocInfo = CCValAssign::SExt;
2105    else if (ArgFlags.isZExt())
2106      LocInfo = CCValAssign::ZExt;
2107    else
2108      LocInfo = CCValAssign::AExt;
2109  }
2110
2111  unsigned Reg;
2112
2113  // f32 and f64 are allocated in A0, A1, A2, A3 when either of the following
2114  // is true: function is vararg, argument is 3rd or higher, there is previous
2115  // argument which is not f32 or f64.
2116  bool AllocateFloatsInIntReg = State.isVarArg() || ValNo > 1
2117      || State.getFirstUnallocated(F32Regs, FloatRegsSize) != ValNo;
2118  unsigned OrigAlign = ArgFlags.getOrigAlign();
2119  bool isI64 = (ValVT == MVT::i32 && OrigAlign == 8);
2120
2121  if (ValVT == MVT::i32 || (ValVT == MVT::f32 && AllocateFloatsInIntReg)) {
2122    Reg = State.AllocateReg(IntRegs, IntRegsSize);
2123    // If this is the first part of an i64 arg,
2124    // the allocated register must be either A0 or A2.
2125    if (isI64 && (Reg == Mips::A1 || Reg == Mips::A3))
2126      Reg = State.AllocateReg(IntRegs, IntRegsSize);
2127    LocVT = MVT::i32;
2128  } else if (ValVT == MVT::f64 && AllocateFloatsInIntReg) {
2129    // Allocate int register and shadow next int register. If first
2130    // available register is Mips::A1 or Mips::A3, shadow it too.
2131    Reg = State.AllocateReg(IntRegs, IntRegsSize);
2132    if (Reg == Mips::A1 || Reg == Mips::A3)
2133      Reg = State.AllocateReg(IntRegs, IntRegsSize);
2134    State.AllocateReg(IntRegs, IntRegsSize);
2135    LocVT = MVT::i32;
2136  } else if (ValVT.isFloatingPoint() && !AllocateFloatsInIntReg) {
2137    // we are guaranteed to find an available float register
2138    if (ValVT == MVT::f32) {
2139      Reg = State.AllocateReg(F32Regs, FloatRegsSize);
2140      // Shadow int register
2141      State.AllocateReg(IntRegs, IntRegsSize);
2142    } else {
2143      Reg = State.AllocateReg(F64Regs, FloatRegsSize);
2144      // Shadow int registers
2145      unsigned Reg2 = State.AllocateReg(IntRegs, IntRegsSize);
2146      if (Reg2 == Mips::A1 || Reg2 == Mips::A3)
2147        State.AllocateReg(IntRegs, IntRegsSize);
2148      State.AllocateReg(IntRegs, IntRegsSize);
2149    }
2150  } else
2151    llvm_unreachable("Cannot handle this ValVT.");
2152
2153  if (!Reg) {
2154    unsigned Offset = State.AllocateStack(ValVT.getSizeInBits() >> 3,
2155                                          OrigAlign);
2156    State.addLoc(CCValAssign::getMem(ValNo, ValVT, Offset, LocVT, LocInfo));
2157  } else
2158    State.addLoc(CCValAssign::getReg(ValNo, ValVT, Reg, LocVT, LocInfo));
2159
2160  return false;
2161}
2162
2163#include "MipsGenCallingConv.inc"
2164
2165//===----------------------------------------------------------------------===//
2166//                  Call Calling Convention Implementation
2167//===----------------------------------------------------------------------===//
2168
2169static const unsigned O32IntRegsSize = 4;
2170
2171// Return next O32 integer argument register.
2172static unsigned getNextIntArgReg(unsigned Reg) {
2173  assert((Reg == Mips::A0) || (Reg == Mips::A2));
2174  return (Reg == Mips::A0) ? Mips::A1 : Mips::A3;
2175}
2176
2177SDValue
2178MipsTargetLowering::passArgOnStack(SDValue StackPtr, unsigned Offset,
2179                                   SDValue Chain, SDValue Arg, DebugLoc DL,
2180                                   bool IsTailCall, SelectionDAG &DAG) const {
2181  if (!IsTailCall) {
2182    SDValue PtrOff = DAG.getNode(ISD::ADD, DL, getPointerTy(), StackPtr,
2183                                 DAG.getIntPtrConstant(Offset));
2184    return DAG.getStore(Chain, DL, Arg, PtrOff, MachinePointerInfo(), false,
2185                        false, 0);
2186  }
2187
2188  MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo();
2189  int FI = MFI->CreateFixedObject(Arg.getValueSizeInBits() / 8, Offset, false);
2190  SDValue FIN = DAG.getFrameIndex(FI, getPointerTy());
2191  return DAG.getStore(Chain, DL, Arg, FIN, MachinePointerInfo(),
2192                      /*isVolatile=*/ true, false, 0);
2193}
2194
2195void MipsTargetLowering::
2196getOpndList(SmallVectorImpl<SDValue> &Ops,
2197            std::deque< std::pair<unsigned, SDValue> > &RegsToPass,
2198            bool IsPICCall, bool GlobalOrExternal, bool InternalLinkage,
2199            CallLoweringInfo &CLI, SDValue Callee, SDValue Chain) const {
2200  // Insert node "GP copy globalreg" before call to function.
2201  //
2202  // R_MIPS_CALL* operators (emitted when non-internal functions are called
2203  // in PIC mode) allow symbols to be resolved via lazy binding.
2204  // The lazy binding stub requires GP to point to the GOT.
2205  if (IsPICCall && !InternalLinkage) {
2206    unsigned GPReg = IsN64 ? Mips::GP_64 : Mips::GP;
2207    EVT Ty = IsN64 ? MVT::i64 : MVT::i32;
2208    RegsToPass.push_back(std::make_pair(GPReg, getGlobalReg(CLI.DAG, Ty)));
2209  }
2210
2211  // Build a sequence of copy-to-reg nodes chained together with token
2212  // chain and flag operands which copy the outgoing args into registers.
2213  // The InFlag in necessary since all emitted instructions must be
2214  // stuck together.
2215  SDValue InFlag;
2216
2217  for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i) {
2218    Chain = CLI.DAG.getCopyToReg(Chain, CLI.DL, RegsToPass[i].first,
2219                                 RegsToPass[i].second, InFlag);
2220    InFlag = Chain.getValue(1);
2221  }
2222
2223  // Add argument registers to the end of the list so that they are
2224  // known live into the call.
2225  for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i)
2226    Ops.push_back(CLI.DAG.getRegister(RegsToPass[i].first,
2227                                      RegsToPass[i].second.getValueType()));
2228
2229  // Add a register mask operand representing the call-preserved registers.
2230  const TargetRegisterInfo *TRI = getTargetMachine().getRegisterInfo();
2231  const uint32_t *Mask = TRI->getCallPreservedMask(CLI.CallConv);
2232  assert(Mask && "Missing call preserved mask for calling convention");
2233  Ops.push_back(CLI.DAG.getRegisterMask(Mask));
2234
2235  if (InFlag.getNode())
2236    Ops.push_back(InFlag);
2237}
2238
2239/// LowerCall - functions arguments are copied from virtual regs to
2240/// (physical regs)/(stack frame), CALLSEQ_START and CALLSEQ_END are emitted.
2241SDValue
2242MipsTargetLowering::LowerCall(TargetLowering::CallLoweringInfo &CLI,
2243                              SmallVectorImpl<SDValue> &InVals) const {
2244  SelectionDAG &DAG                     = CLI.DAG;
2245  DebugLoc &DL                          = CLI.DL;
2246  SmallVector<ISD::OutputArg, 32> &Outs = CLI.Outs;
2247  SmallVector<SDValue, 32> &OutVals     = CLI.OutVals;
2248  SmallVector<ISD::InputArg, 32> &Ins   = CLI.Ins;
2249  SDValue Chain                         = CLI.Chain;
2250  SDValue Callee                        = CLI.Callee;
2251  bool &IsTailCall                      = CLI.IsTailCall;
2252  CallingConv::ID CallConv              = CLI.CallConv;
2253  bool IsVarArg                         = CLI.IsVarArg;
2254
2255  MachineFunction &MF = DAG.getMachineFunction();
2256  MachineFrameInfo *MFI = MF.getFrameInfo();
2257  const TargetFrameLowering *TFL = MF.getTarget().getFrameLowering();
2258  bool IsPIC = getTargetMachine().getRelocationModel() == Reloc::PIC_;
2259
2260  // Analyze operands of the call, assigning locations to each operand.
2261  SmallVector<CCValAssign, 16> ArgLocs;
2262  CCState CCInfo(CallConv, IsVarArg, DAG.getMachineFunction(),
2263                 getTargetMachine(), ArgLocs, *DAG.getContext());
2264  MipsCC MipsCCInfo(CallConv, IsO32, CCInfo);
2265
2266  MipsCCInfo.analyzeCallOperands(Outs, IsVarArg,
2267                                 getTargetMachine().Options.UseSoftFloat,
2268                                 Callee.getNode(), CLI.Args);
2269
2270  // Get a count of how many bytes are to be pushed on the stack.
2271  unsigned NextStackOffset = CCInfo.getNextStackOffset();
2272
2273  // Check if it's really possible to do a tail call.
2274  if (IsTailCall)
2275    IsTailCall =
2276      isEligibleForTailCallOptimization(MipsCCInfo, NextStackOffset,
2277                                        *MF.getInfo<MipsFunctionInfo>());
2278
2279  if (IsTailCall)
2280    ++NumTailCalls;
2281
2282  // Chain is the output chain of the last Load/Store or CopyToReg node.
2283  // ByValChain is the output chain of the last Memcpy node created for copying
2284  // byval arguments to the stack.
2285  unsigned StackAlignment = TFL->getStackAlignment();
2286  NextStackOffset = RoundUpToAlignment(NextStackOffset, StackAlignment);
2287  SDValue NextStackOffsetVal = DAG.getIntPtrConstant(NextStackOffset, true);
2288
2289  if (!IsTailCall)
2290    Chain = DAG.getCALLSEQ_START(Chain, NextStackOffsetVal);
2291
2292  SDValue StackPtr = DAG.getCopyFromReg(Chain, DL,
2293                                        IsN64 ? Mips::SP_64 : Mips::SP,
2294                                        getPointerTy());
2295
2296  // With EABI is it possible to have 16 args on registers.
2297  std::deque< std::pair<unsigned, SDValue> > RegsToPass;
2298  SmallVector<SDValue, 8> MemOpChains;
2299  MipsCC::byval_iterator ByValArg = MipsCCInfo.byval_begin();
2300
2301  // Walk the register/memloc assignments, inserting copies/loads.
2302  for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
2303    SDValue Arg = OutVals[i];
2304    CCValAssign &VA = ArgLocs[i];
2305    MVT ValVT = VA.getValVT(), LocVT = VA.getLocVT();
2306    ISD::ArgFlagsTy Flags = Outs[i].Flags;
2307
2308    // ByVal Arg.
2309    if (Flags.isByVal()) {
2310      assert(Flags.getByValSize() &&
2311             "ByVal args of size 0 should have been ignored by front-end.");
2312      assert(ByValArg != MipsCCInfo.byval_end());
2313      assert(!IsTailCall &&
2314             "Do not tail-call optimize if there is a byval argument.");
2315      passByValArg(Chain, DL, RegsToPass, MemOpChains, StackPtr, MFI, DAG, Arg,
2316                   MipsCCInfo, *ByValArg, Flags, Subtarget->isLittle());
2317      ++ByValArg;
2318      continue;
2319    }
2320
2321    // Promote the value if needed.
2322    switch (VA.getLocInfo()) {
2323    default: llvm_unreachable("Unknown loc info!");
2324    case CCValAssign::Full:
2325      if (VA.isRegLoc()) {
2326        if ((ValVT == MVT::f32 && LocVT == MVT::i32) ||
2327            (ValVT == MVT::f64 && LocVT == MVT::i64) ||
2328            (ValVT == MVT::i64 && LocVT == MVT::f64))
2329          Arg = DAG.getNode(ISD::BITCAST, DL, LocVT, Arg);
2330        else if (ValVT == MVT::f64 && LocVT == MVT::i32) {
2331          SDValue Lo = DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32,
2332                                   Arg, DAG.getConstant(0, MVT::i32));
2333          SDValue Hi = DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32,
2334                                   Arg, DAG.getConstant(1, MVT::i32));
2335          if (!Subtarget->isLittle())
2336            std::swap(Lo, Hi);
2337          unsigned LocRegLo = VA.getLocReg();
2338          unsigned LocRegHigh = getNextIntArgReg(LocRegLo);
2339          RegsToPass.push_back(std::make_pair(LocRegLo, Lo));
2340          RegsToPass.push_back(std::make_pair(LocRegHigh, Hi));
2341          continue;
2342        }
2343      }
2344      break;
2345    case CCValAssign::SExt:
2346      Arg = DAG.getNode(ISD::SIGN_EXTEND, DL, LocVT, Arg);
2347      break;
2348    case CCValAssign::ZExt:
2349      Arg = DAG.getNode(ISD::ZERO_EXTEND, DL, LocVT, Arg);
2350      break;
2351    case CCValAssign::AExt:
2352      Arg = DAG.getNode(ISD::ANY_EXTEND, DL, LocVT, Arg);
2353      break;
2354    }
2355
2356    // Arguments that can be passed on register must be kept at
2357    // RegsToPass vector
2358    if (VA.isRegLoc()) {
2359      RegsToPass.push_back(std::make_pair(VA.getLocReg(), Arg));
2360      continue;
2361    }
2362
2363    // Register can't get to this point...
2364    assert(VA.isMemLoc());
2365
2366    // emit ISD::STORE whichs stores the
2367    // parameter value to a stack Location
2368    MemOpChains.push_back(passArgOnStack(StackPtr, VA.getLocMemOffset(),
2369                                         Chain, Arg, DL, IsTailCall, DAG));
2370  }
2371
2372  // Transform all store nodes into one single node because all store
2373  // nodes are independent of each other.
2374  if (!MemOpChains.empty())
2375    Chain = DAG.getNode(ISD::TokenFactor, DL, MVT::Other,
2376                        &MemOpChains[0], MemOpChains.size());
2377
2378  // If the callee is a GlobalAddress/ExternalSymbol node (quite common, every
2379  // direct call is) turn it into a TargetGlobalAddress/TargetExternalSymbol
2380  // node so that legalize doesn't hack it.
2381  bool IsPICCall = (IsN64 || IsPIC); // true if calls are translated to jalr $25
2382  bool GlobalOrExternal = false, InternalLinkage = false;
2383  SDValue CalleeLo;
2384
2385  if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee)) {
2386    if (IsPICCall) {
2387      InternalLinkage = G->getGlobal()->hasInternalLinkage();
2388
2389      if (InternalLinkage)
2390        Callee = getAddrLocal(Callee, DAG, HasMips64);
2391      else if (LargeGOT)
2392        Callee = getAddrGlobalLargeGOT(Callee, DAG, MipsII::MO_CALL_HI16,
2393                                       MipsII::MO_CALL_LO16);
2394      else
2395        Callee = getAddrGlobal(Callee, DAG, MipsII::MO_GOT_CALL);
2396    } else
2397      Callee = DAG.getTargetGlobalAddress(G->getGlobal(), DL, getPointerTy(), 0,
2398                                          MipsII::MO_NO_FLAG);
2399    GlobalOrExternal = true;
2400  }
2401  else if (ExternalSymbolSDNode *S = dyn_cast<ExternalSymbolSDNode>(Callee)) {
2402    if (!IsN64 && !IsPIC) // !N64 && static
2403      Callee = DAG.getTargetExternalSymbol(S->getSymbol(), getPointerTy(),
2404                                            MipsII::MO_NO_FLAG);
2405    else if (LargeGOT)
2406      Callee = getAddrGlobalLargeGOT(Callee, DAG, MipsII::MO_CALL_HI16,
2407                                     MipsII::MO_CALL_LO16);
2408    else // N64 || PIC
2409      Callee = getAddrGlobal(Callee, DAG, MipsII::MO_GOT_CALL);
2410
2411    GlobalOrExternal = true;
2412  }
2413
2414  SmallVector<SDValue, 8> Ops(1, Chain);
2415  SDVTList NodeTys = DAG.getVTList(MVT::Other, MVT::Glue);
2416
2417  getOpndList(Ops, RegsToPass, IsPICCall, GlobalOrExternal, InternalLinkage,
2418              CLI, Callee, Chain);
2419
2420  if (IsTailCall)
2421    return DAG.getNode(MipsISD::TailCall, DL, MVT::Other, &Ops[0], Ops.size());
2422
2423  Chain  = DAG.getNode(MipsISD::JmpLink, DL, NodeTys, &Ops[0], Ops.size());
2424  SDValue InFlag = Chain.getValue(1);
2425
2426  // Create the CALLSEQ_END node.
2427  Chain = DAG.getCALLSEQ_END(Chain, NextStackOffsetVal,
2428                             DAG.getIntPtrConstant(0, true), InFlag);
2429  InFlag = Chain.getValue(1);
2430
2431  // Handle result values, copying them out of physregs into vregs that we
2432  // return.
2433  return LowerCallResult(Chain, InFlag, CallConv, IsVarArg,
2434                         Ins, DL, DAG, InVals, CLI.Callee.getNode(), CLI.RetTy);
2435}
2436
2437/// LowerCallResult - Lower the result values of a call into the
2438/// appropriate copies out of appropriate physical registers.
2439SDValue
2440MipsTargetLowering::LowerCallResult(SDValue Chain, SDValue InFlag,
2441                                    CallingConv::ID CallConv, bool IsVarArg,
2442                                    const SmallVectorImpl<ISD::InputArg> &Ins,
2443                                    DebugLoc DL, SelectionDAG &DAG,
2444                                    SmallVectorImpl<SDValue> &InVals,
2445                                    const SDNode *CallNode,
2446                                    const Type *RetTy) const {
2447  // Assign locations to each value returned by this call.
2448  SmallVector<CCValAssign, 16> RVLocs;
2449  CCState CCInfo(CallConv, IsVarArg, DAG.getMachineFunction(),
2450                 getTargetMachine(), RVLocs, *DAG.getContext());
2451  MipsCC MipsCCInfo(CallConv, IsO32, CCInfo);
2452
2453  MipsCCInfo.analyzeCallResult(Ins, getTargetMachine().Options.UseSoftFloat,
2454                               CallNode, RetTy);
2455
2456  // Copy all of the result registers out of their specified physreg.
2457  for (unsigned i = 0; i != RVLocs.size(); ++i) {
2458    SDValue Val = DAG.getCopyFromReg(Chain, DL, RVLocs[i].getLocReg(),
2459                                     RVLocs[i].getLocVT(), InFlag);
2460    Chain = Val.getValue(1);
2461    InFlag = Val.getValue(2);
2462
2463    if (RVLocs[i].getValVT() != RVLocs[i].getLocVT())
2464      Val = DAG.getNode(ISD::BITCAST, DL, RVLocs[i].getValVT(), Val);
2465
2466    InVals.push_back(Val);
2467  }
2468
2469  return Chain;
2470}
2471
2472//===----------------------------------------------------------------------===//
2473//             Formal Arguments Calling Convention Implementation
2474//===----------------------------------------------------------------------===//
2475/// LowerFormalArguments - transform physical registers into virtual registers
2476/// and generate load operations for arguments places on the stack.
2477SDValue
2478MipsTargetLowering::LowerFormalArguments(SDValue Chain,
2479                                         CallingConv::ID CallConv,
2480                                         bool IsVarArg,
2481                                      const SmallVectorImpl<ISD::InputArg> &Ins,
2482                                         DebugLoc DL, SelectionDAG &DAG,
2483                                         SmallVectorImpl<SDValue> &InVals)
2484                                          const {
2485  MachineFunction &MF = DAG.getMachineFunction();
2486  MachineFrameInfo *MFI = MF.getFrameInfo();
2487  MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
2488
2489  MipsFI->setVarArgsFrameIndex(0);
2490
2491  // Used with vargs to acumulate store chains.
2492  std::vector<SDValue> OutChains;
2493
2494  // Assign locations to all of the incoming arguments.
2495  SmallVector<CCValAssign, 16> ArgLocs;
2496  CCState CCInfo(CallConv, IsVarArg, DAG.getMachineFunction(),
2497                 getTargetMachine(), ArgLocs, *DAG.getContext());
2498  MipsCC MipsCCInfo(CallConv, IsO32, CCInfo);
2499  Function::const_arg_iterator FuncArg =
2500    DAG.getMachineFunction().getFunction()->arg_begin();
2501  bool UseSoftFloat = getTargetMachine().Options.UseSoftFloat;
2502
2503  MipsCCInfo.analyzeFormalArguments(Ins, UseSoftFloat, FuncArg);
2504  MipsFI->setFormalArgInfo(CCInfo.getNextStackOffset(),
2505                           MipsCCInfo.hasByValArg());
2506
2507  unsigned CurArgIdx = 0;
2508  MipsCC::byval_iterator ByValArg = MipsCCInfo.byval_begin();
2509
2510  for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
2511    CCValAssign &VA = ArgLocs[i];
2512    std::advance(FuncArg, Ins[i].OrigArgIndex - CurArgIdx);
2513    CurArgIdx = Ins[i].OrigArgIndex;
2514    EVT ValVT = VA.getValVT();
2515    ISD::ArgFlagsTy Flags = Ins[i].Flags;
2516    bool IsRegLoc = VA.isRegLoc();
2517
2518    if (Flags.isByVal()) {
2519      assert(Flags.getByValSize() &&
2520             "ByVal args of size 0 should have been ignored by front-end.");
2521      assert(ByValArg != MipsCCInfo.byval_end());
2522      copyByValRegs(Chain, DL, OutChains, DAG, Flags, InVals, &*FuncArg,
2523                    MipsCCInfo, *ByValArg);
2524      ++ByValArg;
2525      continue;
2526    }
2527
2528    // Arguments stored on registers
2529    if (IsRegLoc) {
2530      EVT RegVT = VA.getLocVT();
2531      unsigned ArgReg = VA.getLocReg();
2532      const TargetRegisterClass *RC;
2533
2534      if (RegVT == MVT::i32)
2535        RC = Subtarget->inMips16Mode()? &Mips::CPU16RegsRegClass :
2536                                        &Mips::CPURegsRegClass;
2537      else if (RegVT == MVT::i64)
2538        RC = &Mips::CPU64RegsRegClass;
2539      else if (RegVT == MVT::f32)
2540        RC = &Mips::FGR32RegClass;
2541      else if (RegVT == MVT::f64)
2542        RC = HasMips64 ? &Mips::FGR64RegClass : &Mips::AFGR64RegClass;
2543      else
2544        llvm_unreachable("RegVT not supported by FormalArguments Lowering");
2545
2546      // Transform the arguments stored on
2547      // physical registers into virtual ones
2548      unsigned Reg = addLiveIn(DAG.getMachineFunction(), ArgReg, RC);
2549      SDValue ArgValue = DAG.getCopyFromReg(Chain, DL, Reg, RegVT);
2550
2551      // If this is an 8 or 16-bit value, it has been passed promoted
2552      // to 32 bits.  Insert an assert[sz]ext to capture this, then
2553      // truncate to the right size.
2554      if (VA.getLocInfo() != CCValAssign::Full) {
2555        unsigned Opcode = 0;
2556        if (VA.getLocInfo() == CCValAssign::SExt)
2557          Opcode = ISD::AssertSext;
2558        else if (VA.getLocInfo() == CCValAssign::ZExt)
2559          Opcode = ISD::AssertZext;
2560        if (Opcode)
2561          ArgValue = DAG.getNode(Opcode, DL, RegVT, ArgValue,
2562                                 DAG.getValueType(ValVT));
2563        ArgValue = DAG.getNode(ISD::TRUNCATE, DL, ValVT, ArgValue);
2564      }
2565
2566      // Handle floating point arguments passed in integer registers and
2567      // long double arguments passed in floating point registers.
2568      if ((RegVT == MVT::i32 && ValVT == MVT::f32) ||
2569          (RegVT == MVT::i64 && ValVT == MVT::f64) ||
2570          (RegVT == MVT::f64 && ValVT == MVT::i64))
2571        ArgValue = DAG.getNode(ISD::BITCAST, DL, ValVT, ArgValue);
2572      else if (IsO32 && RegVT == MVT::i32 && ValVT == MVT::f64) {
2573        unsigned Reg2 = addLiveIn(DAG.getMachineFunction(),
2574                                  getNextIntArgReg(ArgReg), RC);
2575        SDValue ArgValue2 = DAG.getCopyFromReg(Chain, DL, Reg2, RegVT);
2576        if (!Subtarget->isLittle())
2577          std::swap(ArgValue, ArgValue2);
2578        ArgValue = DAG.getNode(MipsISD::BuildPairF64, DL, MVT::f64,
2579                               ArgValue, ArgValue2);
2580      }
2581
2582      InVals.push_back(ArgValue);
2583    } else { // VA.isRegLoc()
2584
2585      // sanity check
2586      assert(VA.isMemLoc());
2587
2588      // The stack pointer offset is relative to the caller stack frame.
2589      int FI = MFI->CreateFixedObject(ValVT.getSizeInBits()/8,
2590                                      VA.getLocMemOffset(), true);
2591
2592      // Create load nodes to retrieve arguments from the stack
2593      SDValue FIN = DAG.getFrameIndex(FI, getPointerTy());
2594      InVals.push_back(DAG.getLoad(ValVT, DL, Chain, FIN,
2595                                   MachinePointerInfo::getFixedStack(FI),
2596                                   false, false, false, 0));
2597    }
2598  }
2599
2600  // The mips ABIs for returning structs by value requires that we copy
2601  // the sret argument into $v0 for the return. Save the argument into
2602  // a virtual register so that we can access it from the return points.
2603  if (DAG.getMachineFunction().getFunction()->hasStructRetAttr()) {
2604    unsigned Reg = MipsFI->getSRetReturnReg();
2605    if (!Reg) {
2606      Reg = MF.getRegInfo().
2607        createVirtualRegister(getRegClassFor(IsN64 ? MVT::i64 : MVT::i32));
2608      MipsFI->setSRetReturnReg(Reg);
2609    }
2610    SDValue Copy = DAG.getCopyToReg(DAG.getEntryNode(), DL, Reg, InVals[0]);
2611    Chain = DAG.getNode(ISD::TokenFactor, DL, MVT::Other, Copy, Chain);
2612  }
2613
2614  if (IsVarArg)
2615    writeVarArgRegs(OutChains, MipsCCInfo, Chain, DL, DAG);
2616
2617  // All stores are grouped in one node to allow the matching between
2618  // the size of Ins and InVals. This only happens when on varg functions
2619  if (!OutChains.empty()) {
2620    OutChains.push_back(Chain);
2621    Chain = DAG.getNode(ISD::TokenFactor, DL, MVT::Other,
2622                        &OutChains[0], OutChains.size());
2623  }
2624
2625  return Chain;
2626}
2627
2628//===----------------------------------------------------------------------===//
2629//               Return Value Calling Convention Implementation
2630//===----------------------------------------------------------------------===//
2631
2632bool
2633MipsTargetLowering::CanLowerReturn(CallingConv::ID CallConv,
2634                                   MachineFunction &MF, bool IsVarArg,
2635                                   const SmallVectorImpl<ISD::OutputArg> &Outs,
2636                                   LLVMContext &Context) const {
2637  SmallVector<CCValAssign, 16> RVLocs;
2638  CCState CCInfo(CallConv, IsVarArg, MF, getTargetMachine(),
2639                 RVLocs, Context);
2640  return CCInfo.CheckReturn(Outs, RetCC_Mips);
2641}
2642
2643SDValue
2644MipsTargetLowering::LowerReturn(SDValue Chain,
2645                                CallingConv::ID CallConv, bool IsVarArg,
2646                                const SmallVectorImpl<ISD::OutputArg> &Outs,
2647                                const SmallVectorImpl<SDValue> &OutVals,
2648                                DebugLoc DL, SelectionDAG &DAG) const {
2649  // CCValAssign - represent the assignment of
2650  // the return value to a location
2651  SmallVector<CCValAssign, 16> RVLocs;
2652  MachineFunction &MF = DAG.getMachineFunction();
2653
2654  // CCState - Info about the registers and stack slot.
2655  CCState CCInfo(CallConv, IsVarArg, MF, getTargetMachine(), RVLocs,
2656                 *DAG.getContext());
2657  MipsCC MipsCCInfo(CallConv, IsO32, CCInfo);
2658
2659  // Analyze return values.
2660  MipsCCInfo.analyzeReturn(Outs, getTargetMachine().Options.UseSoftFloat,
2661                           MF.getFunction()->getReturnType());
2662
2663  SDValue Flag;
2664  SmallVector<SDValue, 4> RetOps(1, Chain);
2665
2666  // Copy the result values into the output registers.
2667  for (unsigned i = 0; i != RVLocs.size(); ++i) {
2668    SDValue Val = OutVals[i];
2669    CCValAssign &VA = RVLocs[i];
2670    assert(VA.isRegLoc() && "Can only return in registers!");
2671
2672    if (RVLocs[i].getValVT() != RVLocs[i].getLocVT())
2673      Val = DAG.getNode(ISD::BITCAST, DL, RVLocs[i].getLocVT(), Val);
2674
2675    Chain = DAG.getCopyToReg(Chain, DL, VA.getLocReg(), Val, Flag);
2676
2677    // Guarantee that all emitted copies are stuck together with flags.
2678    Flag = Chain.getValue(1);
2679    RetOps.push_back(DAG.getRegister(VA.getLocReg(), VA.getLocVT()));
2680  }
2681
2682  // The mips ABIs for returning structs by value requires that we copy
2683  // the sret argument into $v0 for the return. We saved the argument into
2684  // a virtual register in the entry block, so now we copy the value out
2685  // and into $v0.
2686  if (MF.getFunction()->hasStructRetAttr()) {
2687    MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
2688    unsigned Reg = MipsFI->getSRetReturnReg();
2689
2690    if (!Reg)
2691      llvm_unreachable("sret virtual register not created in the entry block");
2692    SDValue Val = DAG.getCopyFromReg(Chain, DL, Reg, getPointerTy());
2693    unsigned V0 = IsN64 ? Mips::V0_64 : Mips::V0;
2694
2695    Chain = DAG.getCopyToReg(Chain, DL, V0, Val, Flag);
2696    Flag = Chain.getValue(1);
2697    RetOps.push_back(DAG.getRegister(V0, getPointerTy()));
2698  }
2699
2700  RetOps[0] = Chain;  // Update chain.
2701
2702  // Add the flag if we have it.
2703  if (Flag.getNode())
2704    RetOps.push_back(Flag);
2705
2706  // Return on Mips is always a "jr $ra"
2707  return DAG.getNode(MipsISD::Ret, DL, MVT::Other, &RetOps[0], RetOps.size());
2708}
2709
2710//===----------------------------------------------------------------------===//
2711//                           Mips Inline Assembly Support
2712//===----------------------------------------------------------------------===//
2713
2714/// getConstraintType - Given a constraint letter, return the type of
2715/// constraint it is for this target.
2716MipsTargetLowering::ConstraintType MipsTargetLowering::
2717getConstraintType(const std::string &Constraint) const
2718{
2719  // Mips specific constrainy
2720  // GCC config/mips/constraints.md
2721  //
2722  // 'd' : An address register. Equivalent to r
2723  //       unless generating MIPS16 code.
2724  // 'y' : Equivalent to r; retained for
2725  //       backwards compatibility.
2726  // 'c' : A register suitable for use in an indirect
2727  //       jump. This will always be $25 for -mabicalls.
2728  // 'l' : The lo register. 1 word storage.
2729  // 'x' : The hilo register pair. Double word storage.
2730  if (Constraint.size() == 1) {
2731    switch (Constraint[0]) {
2732      default : break;
2733      case 'd':
2734      case 'y':
2735      case 'f':
2736      case 'c':
2737      case 'l':
2738      case 'x':
2739        return C_RegisterClass;
2740      case 'R':
2741        return C_Memory;
2742    }
2743  }
2744  return TargetLowering::getConstraintType(Constraint);
2745}
2746
2747/// Examine constraint type and operand type and determine a weight value.
2748/// This object must already have been set up with the operand type
2749/// and the current alternative constraint selected.
2750TargetLowering::ConstraintWeight
2751MipsTargetLowering::getSingleConstraintMatchWeight(
2752    AsmOperandInfo &info, const char *constraint) const {
2753  ConstraintWeight weight = CW_Invalid;
2754  Value *CallOperandVal = info.CallOperandVal;
2755    // If we don't have a value, we can't do a match,
2756    // but allow it at the lowest weight.
2757  if (CallOperandVal == NULL)
2758    return CW_Default;
2759  Type *type = CallOperandVal->getType();
2760  // Look at the constraint type.
2761  switch (*constraint) {
2762  default:
2763    weight = TargetLowering::getSingleConstraintMatchWeight(info, constraint);
2764    break;
2765  case 'd':
2766  case 'y':
2767    if (type->isIntegerTy())
2768      weight = CW_Register;
2769    break;
2770  case 'f':
2771    if (type->isFloatTy())
2772      weight = CW_Register;
2773    break;
2774  case 'c': // $25 for indirect jumps
2775  case 'l': // lo register
2776  case 'x': // hilo register pair
2777      if (type->isIntegerTy())
2778      weight = CW_SpecificReg;
2779      break;
2780  case 'I': // signed 16 bit immediate
2781  case 'J': // integer zero
2782  case 'K': // unsigned 16 bit immediate
2783  case 'L': // signed 32 bit immediate where lower 16 bits are 0
2784  case 'N': // immediate in the range of -65535 to -1 (inclusive)
2785  case 'O': // signed 15 bit immediate (+- 16383)
2786  case 'P': // immediate in the range of 65535 to 1 (inclusive)
2787    if (isa<ConstantInt>(CallOperandVal))
2788      weight = CW_Constant;
2789    break;
2790  case 'R':
2791    weight = CW_Memory;
2792    break;
2793  }
2794  return weight;
2795}
2796
2797/// Given a register class constraint, like 'r', if this corresponds directly
2798/// to an LLVM register class, return a register of 0 and the register class
2799/// pointer.
2800std::pair<unsigned, const TargetRegisterClass*> MipsTargetLowering::
2801getRegForInlineAsmConstraint(const std::string &Constraint, EVT VT) const
2802{
2803  if (Constraint.size() == 1) {
2804    switch (Constraint[0]) {
2805    case 'd': // Address register. Same as 'r' unless generating MIPS16 code.
2806    case 'y': // Same as 'r'. Exists for compatibility.
2807    case 'r':
2808      if (VT == MVT::i32 || VT == MVT::i16 || VT == MVT::i8) {
2809        if (Subtarget->inMips16Mode())
2810          return std::make_pair(0U, &Mips::CPU16RegsRegClass);
2811        return std::make_pair(0U, &Mips::CPURegsRegClass);
2812      }
2813      if (VT == MVT::i64 && !HasMips64)
2814        return std::make_pair(0U, &Mips::CPURegsRegClass);
2815      if (VT == MVT::i64 && HasMips64)
2816        return std::make_pair(0U, &Mips::CPU64RegsRegClass);
2817      // This will generate an error message
2818      return std::make_pair(0u, static_cast<const TargetRegisterClass*>(0));
2819    case 'f':
2820      if (VT == MVT::f32)
2821        return std::make_pair(0U, &Mips::FGR32RegClass);
2822      if ((VT == MVT::f64) && (!Subtarget->isSingleFloat())) {
2823        if (Subtarget->isFP64bit())
2824          return std::make_pair(0U, &Mips::FGR64RegClass);
2825        return std::make_pair(0U, &Mips::AFGR64RegClass);
2826      }
2827      break;
2828    case 'c': // register suitable for indirect jump
2829      if (VT == MVT::i32)
2830        return std::make_pair((unsigned)Mips::T9, &Mips::CPURegsRegClass);
2831      assert(VT == MVT::i64 && "Unexpected type.");
2832      return std::make_pair((unsigned)Mips::T9_64, &Mips::CPU64RegsRegClass);
2833    case 'l': // register suitable for indirect jump
2834      if (VT == MVT::i32)
2835        return std::make_pair((unsigned)Mips::LO, &Mips::HILORegClass);
2836      return std::make_pair((unsigned)Mips::LO64, &Mips::HILO64RegClass);
2837    case 'x': // register suitable for indirect jump
2838      // Fixme: Not triggering the use of both hi and low
2839      // This will generate an error message
2840      return std::make_pair(0u, static_cast<const TargetRegisterClass*>(0));
2841    }
2842  }
2843  return TargetLowering::getRegForInlineAsmConstraint(Constraint, VT);
2844}
2845
2846/// LowerAsmOperandForConstraint - Lower the specified operand into the Ops
2847/// vector.  If it is invalid, don't add anything to Ops.
2848void MipsTargetLowering::LowerAsmOperandForConstraint(SDValue Op,
2849                                                     std::string &Constraint,
2850                                                     std::vector<SDValue>&Ops,
2851                                                     SelectionDAG &DAG) const {
2852  SDValue Result(0, 0);
2853
2854  // Only support length 1 constraints for now.
2855  if (Constraint.length() > 1) return;
2856
2857  char ConstraintLetter = Constraint[0];
2858  switch (ConstraintLetter) {
2859  default: break; // This will fall through to the generic implementation
2860  case 'I': // Signed 16 bit constant
2861    // If this fails, the parent routine will give an error
2862    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
2863      EVT Type = Op.getValueType();
2864      int64_t Val = C->getSExtValue();
2865      if (isInt<16>(Val)) {
2866        Result = DAG.getTargetConstant(Val, Type);
2867        break;
2868      }
2869    }
2870    return;
2871  case 'J': // integer zero
2872    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
2873      EVT Type = Op.getValueType();
2874      int64_t Val = C->getZExtValue();
2875      if (Val == 0) {
2876        Result = DAG.getTargetConstant(0, Type);
2877        break;
2878      }
2879    }
2880    return;
2881  case 'K': // unsigned 16 bit immediate
2882    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
2883      EVT Type = Op.getValueType();
2884      uint64_t Val = (uint64_t)C->getZExtValue();
2885      if (isUInt<16>(Val)) {
2886        Result = DAG.getTargetConstant(Val, Type);
2887        break;
2888      }
2889    }
2890    return;
2891  case 'L': // signed 32 bit immediate where lower 16 bits are 0
2892    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
2893      EVT Type = Op.getValueType();
2894      int64_t Val = C->getSExtValue();
2895      if ((isInt<32>(Val)) && ((Val & 0xffff) == 0)){
2896        Result = DAG.getTargetConstant(Val, Type);
2897        break;
2898      }
2899    }
2900    return;
2901  case 'N': // immediate in the range of -65535 to -1 (inclusive)
2902    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
2903      EVT Type = Op.getValueType();
2904      int64_t Val = C->getSExtValue();
2905      if ((Val >= -65535) && (Val <= -1)) {
2906        Result = DAG.getTargetConstant(Val, Type);
2907        break;
2908      }
2909    }
2910    return;
2911  case 'O': // signed 15 bit immediate
2912    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
2913      EVT Type = Op.getValueType();
2914      int64_t Val = C->getSExtValue();
2915      if ((isInt<15>(Val))) {
2916        Result = DAG.getTargetConstant(Val, Type);
2917        break;
2918      }
2919    }
2920    return;
2921  case 'P': // immediate in the range of 1 to 65535 (inclusive)
2922    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
2923      EVT Type = Op.getValueType();
2924      int64_t Val = C->getSExtValue();
2925      if ((Val <= 65535) && (Val >= 1)) {
2926        Result = DAG.getTargetConstant(Val, Type);
2927        break;
2928      }
2929    }
2930    return;
2931  }
2932
2933  if (Result.getNode()) {
2934    Ops.push_back(Result);
2935    return;
2936  }
2937
2938  TargetLowering::LowerAsmOperandForConstraint(Op, Constraint, Ops, DAG);
2939}
2940
2941bool
2942MipsTargetLowering::isLegalAddressingMode(const AddrMode &AM, Type *Ty) const {
2943  // No global is ever allowed as a base.
2944  if (AM.BaseGV)
2945    return false;
2946
2947  switch (AM.Scale) {
2948  case 0: // "r+i" or just "i", depending on HasBaseReg.
2949    break;
2950  case 1:
2951    if (!AM.HasBaseReg) // allow "r+i".
2952      break;
2953    return false; // disallow "r+r" or "r+r+i".
2954  default:
2955    return false;
2956  }
2957
2958  return true;
2959}
2960
2961bool
2962MipsTargetLowering::isOffsetFoldingLegal(const GlobalAddressSDNode *GA) const {
2963  // The Mips target isn't yet aware of offsets.
2964  return false;
2965}
2966
2967EVT MipsTargetLowering::getOptimalMemOpType(uint64_t Size, unsigned DstAlign,
2968                                            unsigned SrcAlign,
2969                                            bool IsMemset, bool ZeroMemset,
2970                                            bool MemcpyStrSrc,
2971                                            MachineFunction &MF) const {
2972  if (Subtarget->hasMips64())
2973    return MVT::i64;
2974
2975  return MVT::i32;
2976}
2977
2978bool MipsTargetLowering::isFPImmLegal(const APFloat &Imm, EVT VT) const {
2979  if (VT != MVT::f32 && VT != MVT::f64)
2980    return false;
2981  if (Imm.isNegZero())
2982    return false;
2983  return Imm.isZero();
2984}
2985
2986unsigned MipsTargetLowering::getJumpTableEncoding() const {
2987  if (IsN64)
2988    return MachineJumpTableInfo::EK_GPRel64BlockAddress;
2989
2990  return TargetLowering::getJumpTableEncoding();
2991}
2992
2993/// This function returns true if CallSym is a long double emulation routine.
2994static bool isF128SoftLibCall(const char *CallSym) {
2995  const char *const LibCalls[] =
2996    {"__addtf3", "__divtf3", "__eqtf2", "__extenddftf2", "__extendsftf2",
2997     "__fixtfdi", "__fixtfsi", "__fixtfti", "__fixunstfdi", "__fixunstfsi",
2998     "__fixunstfti", "__floatditf", "__floatsitf", "__floattitf",
2999     "__floatunditf", "__floatunsitf", "__floatuntitf", "__getf2", "__gttf2",
3000     "__letf2", "__lttf2", "__multf3", "__netf2", "__powitf2", "__subtf3",
3001     "__trunctfdf2", "__trunctfsf2", "__unordtf2",
3002     "ceill", "copysignl", "cosl", "exp2l", "expl", "floorl", "fmal", "fmodl",
3003     "log10l", "log2l", "logl", "nearbyintl", "powl", "rintl", "sinl", "sqrtl",
3004     "truncl"};
3005
3006  const char * const *End = LibCalls + array_lengthof(LibCalls);
3007
3008  // Check that LibCalls is sorted alphabetically.
3009  MipsTargetLowering::LTStr Comp;
3010
3011#ifndef NDEBUG
3012  for (const char * const *I = LibCalls; I < End - 1; ++I)
3013    assert(Comp(*I, *(I + 1)));
3014#endif
3015
3016  return std::binary_search(LibCalls, End, CallSym, Comp);
3017}
3018
3019/// This function returns true if Ty is fp128 or i128 which was originally a
3020/// fp128.
3021static bool originalTypeIsF128(const Type *Ty, const SDNode *CallNode) {
3022  if (Ty->isFP128Ty())
3023    return true;
3024
3025  const ExternalSymbolSDNode *ES =
3026    dyn_cast_or_null<const ExternalSymbolSDNode>(CallNode);
3027
3028  // If the Ty is i128 and the function being called is a long double emulation
3029  // routine, then the original type is f128.
3030  return (ES && Ty->isIntegerTy(128) && isF128SoftLibCall(ES->getSymbol()));
3031}
3032
3033MipsTargetLowering::MipsCC::MipsCC(CallingConv::ID CC, bool IsO32_,
3034                                   CCState &Info)
3035  : CCInfo(Info), CallConv(CC), IsO32(IsO32_) {
3036  // Pre-allocate reserved argument area.
3037  CCInfo.AllocateStack(reservedArgArea(), 1);
3038}
3039
3040void MipsTargetLowering::MipsCC::
3041analyzeCallOperands(const SmallVectorImpl<ISD::OutputArg> &Args,
3042                    bool IsVarArg, bool IsSoftFloat, const SDNode *CallNode,
3043                    std::vector<ArgListEntry> &FuncArgs) {
3044  assert((CallConv != CallingConv::Fast || !IsVarArg) &&
3045         "CallingConv::Fast shouldn't be used for vararg functions.");
3046
3047  unsigned NumOpnds = Args.size();
3048  llvm::CCAssignFn *FixedFn = fixedArgFn(), *VarFn = varArgFn();
3049
3050  for (unsigned I = 0; I != NumOpnds; ++I) {
3051    MVT ArgVT = Args[I].VT;
3052    ISD::ArgFlagsTy ArgFlags = Args[I].Flags;
3053    bool R;
3054
3055    if (ArgFlags.isByVal()) {
3056      handleByValArg(I, ArgVT, ArgVT, CCValAssign::Full, ArgFlags);
3057      continue;
3058    }
3059
3060    if (IsVarArg && !Args[I].IsFixed)
3061      R = VarFn(I, ArgVT, ArgVT, CCValAssign::Full, ArgFlags, CCInfo);
3062    else {
3063      MVT RegVT = getRegVT(ArgVT, FuncArgs[Args[I].OrigArgIndex].Ty, CallNode,
3064                           IsSoftFloat);
3065      R = FixedFn(I, ArgVT, RegVT, CCValAssign::Full, ArgFlags, CCInfo);
3066    }
3067
3068    if (R) {
3069#ifndef NDEBUG
3070      dbgs() << "Call operand #" << I << " has unhandled type "
3071             << EVT(ArgVT).getEVTString();
3072#endif
3073      llvm_unreachable(0);
3074    }
3075  }
3076}
3077
3078void MipsTargetLowering::MipsCC::
3079analyzeFormalArguments(const SmallVectorImpl<ISD::InputArg> &Args,
3080                       bool IsSoftFloat, Function::const_arg_iterator FuncArg) {
3081  unsigned NumArgs = Args.size();
3082  llvm::CCAssignFn *FixedFn = fixedArgFn();
3083  unsigned CurArgIdx = 0;
3084
3085  for (unsigned I = 0; I != NumArgs; ++I) {
3086    MVT ArgVT = Args[I].VT;
3087    ISD::ArgFlagsTy ArgFlags = Args[I].Flags;
3088    std::advance(FuncArg, Args[I].OrigArgIndex - CurArgIdx);
3089    CurArgIdx = Args[I].OrigArgIndex;
3090
3091    if (ArgFlags.isByVal()) {
3092      handleByValArg(I, ArgVT, ArgVT, CCValAssign::Full, ArgFlags);
3093      continue;
3094    }
3095
3096    MVT RegVT = getRegVT(ArgVT, FuncArg->getType(), 0, IsSoftFloat);
3097
3098    if (!FixedFn(I, ArgVT, RegVT, CCValAssign::Full, ArgFlags, CCInfo))
3099      continue;
3100
3101#ifndef NDEBUG
3102    dbgs() << "Formal Arg #" << I << " has unhandled type "
3103           << EVT(ArgVT).getEVTString();
3104#endif
3105    llvm_unreachable(0);
3106  }
3107}
3108
3109template<typename Ty>
3110void MipsTargetLowering::MipsCC::
3111analyzeReturn(const SmallVectorImpl<Ty> &RetVals, bool IsSoftFloat,
3112              const SDNode *CallNode, const Type *RetTy) const {
3113  CCAssignFn *Fn;
3114
3115  if (IsSoftFloat && originalTypeIsF128(RetTy, CallNode))
3116    Fn = RetCC_F128Soft;
3117  else
3118    Fn = RetCC_Mips;
3119
3120  for (unsigned I = 0, E = RetVals.size(); I < E; ++I) {
3121    MVT VT = RetVals[I].VT;
3122    ISD::ArgFlagsTy Flags = RetVals[I].Flags;
3123    MVT RegVT = this->getRegVT(VT, RetTy, CallNode, IsSoftFloat);
3124
3125    if (Fn(I, VT, RegVT, CCValAssign::Full, Flags, this->CCInfo)) {
3126#ifndef NDEBUG
3127      dbgs() << "Call result #" << I << " has unhandled type "
3128             << EVT(VT).getEVTString() << '\n';
3129#endif
3130      llvm_unreachable(0);
3131    }
3132  }
3133}
3134
3135void MipsTargetLowering::MipsCC::
3136analyzeCallResult(const SmallVectorImpl<ISD::InputArg> &Ins, bool IsSoftFloat,
3137                  const SDNode *CallNode, const Type *RetTy) const {
3138  analyzeReturn(Ins, IsSoftFloat, CallNode, RetTy);
3139}
3140
3141void MipsTargetLowering::MipsCC::
3142analyzeReturn(const SmallVectorImpl<ISD::OutputArg> &Outs, bool IsSoftFloat,
3143              const Type *RetTy) const {
3144  analyzeReturn(Outs, IsSoftFloat, 0, RetTy);
3145}
3146
3147void
3148MipsTargetLowering::MipsCC::handleByValArg(unsigned ValNo, MVT ValVT,
3149                                           MVT LocVT,
3150                                           CCValAssign::LocInfo LocInfo,
3151                                           ISD::ArgFlagsTy ArgFlags) {
3152  assert(ArgFlags.getByValSize() && "Byval argument's size shouldn't be 0.");
3153
3154  struct ByValArgInfo ByVal;
3155  unsigned RegSize = regSize();
3156  unsigned ByValSize = RoundUpToAlignment(ArgFlags.getByValSize(), RegSize);
3157  unsigned Align = std::min(std::max(ArgFlags.getByValAlign(), RegSize),
3158                            RegSize * 2);
3159
3160  if (useRegsForByval())
3161    allocateRegs(ByVal, ByValSize, Align);
3162
3163  // Allocate space on caller's stack.
3164  ByVal.Address = CCInfo.AllocateStack(ByValSize - RegSize * ByVal.NumRegs,
3165                                       Align);
3166  CCInfo.addLoc(CCValAssign::getMem(ValNo, ValVT, ByVal.Address, LocVT,
3167                                    LocInfo));
3168  ByValArgs.push_back(ByVal);
3169}
3170
3171unsigned MipsTargetLowering::MipsCC::numIntArgRegs() const {
3172  return IsO32 ? array_lengthof(O32IntRegs) : array_lengthof(Mips64IntRegs);
3173}
3174
3175unsigned MipsTargetLowering::MipsCC::reservedArgArea() const {
3176  return (IsO32 && (CallConv != CallingConv::Fast)) ? 16 : 0;
3177}
3178
3179const uint16_t *MipsTargetLowering::MipsCC::intArgRegs() const {
3180  return IsO32 ? O32IntRegs : Mips64IntRegs;
3181}
3182
3183llvm::CCAssignFn *MipsTargetLowering::MipsCC::fixedArgFn() const {
3184  if (CallConv == CallingConv::Fast)
3185    return CC_Mips_FastCC;
3186
3187  return IsO32 ? CC_MipsO32 : CC_MipsN;
3188}
3189
3190llvm::CCAssignFn *MipsTargetLowering::MipsCC::varArgFn() const {
3191  return IsO32 ? CC_MipsO32 : CC_MipsN_VarArg;
3192}
3193
3194const uint16_t *MipsTargetLowering::MipsCC::shadowRegs() const {
3195  return IsO32 ? O32IntRegs : Mips64DPRegs;
3196}
3197
3198void MipsTargetLowering::MipsCC::allocateRegs(ByValArgInfo &ByVal,
3199                                              unsigned ByValSize,
3200                                              unsigned Align) {
3201  unsigned RegSize = regSize(), NumIntArgRegs = numIntArgRegs();
3202  const uint16_t *IntArgRegs = intArgRegs(), *ShadowRegs = shadowRegs();
3203  assert(!(ByValSize % RegSize) && !(Align % RegSize) &&
3204         "Byval argument's size and alignment should be a multiple of"
3205         "RegSize.");
3206
3207  ByVal.FirstIdx = CCInfo.getFirstUnallocated(IntArgRegs, NumIntArgRegs);
3208
3209  // If Align > RegSize, the first arg register must be even.
3210  if ((Align > RegSize) && (ByVal.FirstIdx % 2)) {
3211    CCInfo.AllocateReg(IntArgRegs[ByVal.FirstIdx], ShadowRegs[ByVal.FirstIdx]);
3212    ++ByVal.FirstIdx;
3213  }
3214
3215  // Mark the registers allocated.
3216  for (unsigned I = ByVal.FirstIdx; ByValSize && (I < NumIntArgRegs);
3217       ByValSize -= RegSize, ++I, ++ByVal.NumRegs)
3218    CCInfo.AllocateReg(IntArgRegs[I], ShadowRegs[I]);
3219}
3220
3221MVT MipsTargetLowering::MipsCC::getRegVT(MVT VT, const Type *OrigTy,
3222                                         const SDNode *CallNode,
3223                                         bool IsSoftFloat) const {
3224  if (IsSoftFloat || IsO32)
3225    return VT;
3226
3227  // Check if the original type was fp128.
3228  if (originalTypeIsF128(OrigTy, CallNode)) {
3229    assert(VT == MVT::i64);
3230    return MVT::f64;
3231  }
3232
3233  return VT;
3234}
3235
3236void MipsTargetLowering::
3237copyByValRegs(SDValue Chain, DebugLoc DL, std::vector<SDValue> &OutChains,
3238              SelectionDAG &DAG, const ISD::ArgFlagsTy &Flags,
3239              SmallVectorImpl<SDValue> &InVals, const Argument *FuncArg,
3240              const MipsCC &CC, const ByValArgInfo &ByVal) const {
3241  MachineFunction &MF = DAG.getMachineFunction();
3242  MachineFrameInfo *MFI = MF.getFrameInfo();
3243  unsigned RegAreaSize = ByVal.NumRegs * CC.regSize();
3244  unsigned FrameObjSize = std::max(Flags.getByValSize(), RegAreaSize);
3245  int FrameObjOffset;
3246
3247  if (RegAreaSize)
3248    FrameObjOffset = (int)CC.reservedArgArea() -
3249      (int)((CC.numIntArgRegs() - ByVal.FirstIdx) * CC.regSize());
3250  else
3251    FrameObjOffset = ByVal.Address;
3252
3253  // Create frame object.
3254  EVT PtrTy = getPointerTy();
3255  int FI = MFI->CreateFixedObject(FrameObjSize, FrameObjOffset, true);
3256  SDValue FIN = DAG.getFrameIndex(FI, PtrTy);
3257  InVals.push_back(FIN);
3258
3259  if (!ByVal.NumRegs)
3260    return;
3261
3262  // Copy arg registers.
3263  MVT RegTy = MVT::getIntegerVT(CC.regSize() * 8);
3264  const TargetRegisterClass *RC = getRegClassFor(RegTy);
3265
3266  for (unsigned I = 0; I < ByVal.NumRegs; ++I) {
3267    unsigned ArgReg = CC.intArgRegs()[ByVal.FirstIdx + I];
3268    unsigned VReg = addLiveIn(MF, ArgReg, RC);
3269    unsigned Offset = I * CC.regSize();
3270    SDValue StorePtr = DAG.getNode(ISD::ADD, DL, PtrTy, FIN,
3271                                   DAG.getConstant(Offset, PtrTy));
3272    SDValue Store = DAG.getStore(Chain, DL, DAG.getRegister(VReg, RegTy),
3273                                 StorePtr, MachinePointerInfo(FuncArg, Offset),
3274                                 false, false, 0);
3275    OutChains.push_back(Store);
3276  }
3277}
3278
3279// Copy byVal arg to registers and stack.
3280void MipsTargetLowering::
3281passByValArg(SDValue Chain, DebugLoc DL,
3282             std::deque< std::pair<unsigned, SDValue> > &RegsToPass,
3283             SmallVector<SDValue, 8> &MemOpChains, SDValue StackPtr,
3284             MachineFrameInfo *MFI, SelectionDAG &DAG, SDValue Arg,
3285             const MipsCC &CC, const ByValArgInfo &ByVal,
3286             const ISD::ArgFlagsTy &Flags, bool isLittle) const {
3287  unsigned ByValSize = Flags.getByValSize();
3288  unsigned Offset = 0; // Offset in # of bytes from the beginning of struct.
3289  unsigned RegSize = CC.regSize();
3290  unsigned Alignment = std::min(Flags.getByValAlign(), RegSize);
3291  EVT PtrTy = getPointerTy(), RegTy = MVT::getIntegerVT(RegSize * 8);
3292
3293  if (ByVal.NumRegs) {
3294    const uint16_t *ArgRegs = CC.intArgRegs();
3295    bool LeftoverBytes = (ByVal.NumRegs * RegSize > ByValSize);
3296    unsigned I = 0;
3297
3298    // Copy words to registers.
3299    for (; I < ByVal.NumRegs - LeftoverBytes; ++I, Offset += RegSize) {
3300      SDValue LoadPtr = DAG.getNode(ISD::ADD, DL, PtrTy, Arg,
3301                                    DAG.getConstant(Offset, PtrTy));
3302      SDValue LoadVal = DAG.getLoad(RegTy, DL, Chain, LoadPtr,
3303                                    MachinePointerInfo(), false, false, false,
3304                                    Alignment);
3305      MemOpChains.push_back(LoadVal.getValue(1));
3306      unsigned ArgReg = ArgRegs[ByVal.FirstIdx + I];
3307      RegsToPass.push_back(std::make_pair(ArgReg, LoadVal));
3308    }
3309
3310    // Return if the struct has been fully copied.
3311    if (ByValSize == Offset)
3312      return;
3313
3314    // Copy the remainder of the byval argument with sub-word loads and shifts.
3315    if (LeftoverBytes) {
3316      assert((ByValSize > Offset) && (ByValSize < Offset + RegSize) &&
3317             "Size of the remainder should be smaller than RegSize.");
3318      SDValue Val;
3319
3320      for (unsigned LoadSize = RegSize / 2, TotalSizeLoaded = 0;
3321           Offset < ByValSize; LoadSize /= 2) {
3322        unsigned RemSize = ByValSize - Offset;
3323
3324        if (RemSize < LoadSize)
3325          continue;
3326
3327        // Load subword.
3328        SDValue LoadPtr = DAG.getNode(ISD::ADD, DL, PtrTy, Arg,
3329                                      DAG.getConstant(Offset, PtrTy));
3330        SDValue LoadVal =
3331          DAG.getExtLoad(ISD::ZEXTLOAD, DL, RegTy, Chain, LoadPtr,
3332                         MachinePointerInfo(), MVT::getIntegerVT(LoadSize * 8),
3333                         false, false, Alignment);
3334        MemOpChains.push_back(LoadVal.getValue(1));
3335
3336        // Shift the loaded value.
3337        unsigned Shamt;
3338
3339        if (isLittle)
3340          Shamt = TotalSizeLoaded;
3341        else
3342          Shamt = (RegSize - (TotalSizeLoaded + LoadSize)) * 8;
3343
3344        SDValue Shift = DAG.getNode(ISD::SHL, DL, RegTy, LoadVal,
3345                                    DAG.getConstant(Shamt, MVT::i32));
3346
3347        if (Val.getNode())
3348          Val = DAG.getNode(ISD::OR, DL, RegTy, Val, Shift);
3349        else
3350          Val = Shift;
3351
3352        Offset += LoadSize;
3353        TotalSizeLoaded += LoadSize;
3354        Alignment = std::min(Alignment, LoadSize);
3355      }
3356
3357      unsigned ArgReg = ArgRegs[ByVal.FirstIdx + I];
3358      RegsToPass.push_back(std::make_pair(ArgReg, Val));
3359      return;
3360    }
3361  }
3362
3363  // Copy remainder of byval arg to it with memcpy.
3364  unsigned MemCpySize = ByValSize - Offset;
3365  SDValue Src = DAG.getNode(ISD::ADD, DL, PtrTy, Arg,
3366                            DAG.getConstant(Offset, PtrTy));
3367  SDValue Dst = DAG.getNode(ISD::ADD, DL, PtrTy, StackPtr,
3368                            DAG.getIntPtrConstant(ByVal.Address));
3369  Chain = DAG.getMemcpy(Chain, DL, Dst, Src,
3370                        DAG.getConstant(MemCpySize, PtrTy), Alignment,
3371                        /*isVolatile=*/false, /*AlwaysInline=*/false,
3372                        MachinePointerInfo(0), MachinePointerInfo(0));
3373  MemOpChains.push_back(Chain);
3374}
3375
3376void
3377MipsTargetLowering::writeVarArgRegs(std::vector<SDValue> &OutChains,
3378                                    const MipsCC &CC, SDValue Chain,
3379                                    DebugLoc DL, SelectionDAG &DAG) const {
3380  unsigned NumRegs = CC.numIntArgRegs();
3381  const uint16_t *ArgRegs = CC.intArgRegs();
3382  const CCState &CCInfo = CC.getCCInfo();
3383  unsigned Idx = CCInfo.getFirstUnallocated(ArgRegs, NumRegs);
3384  unsigned RegSize = CC.regSize();
3385  MVT RegTy = MVT::getIntegerVT(RegSize * 8);
3386  const TargetRegisterClass *RC = getRegClassFor(RegTy);
3387  MachineFunction &MF = DAG.getMachineFunction();
3388  MachineFrameInfo *MFI = MF.getFrameInfo();
3389  MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
3390
3391  // Offset of the first variable argument from stack pointer.
3392  int VaArgOffset;
3393
3394  if (NumRegs == Idx)
3395    VaArgOffset = RoundUpToAlignment(CCInfo.getNextStackOffset(), RegSize);
3396  else
3397    VaArgOffset =
3398      (int)CC.reservedArgArea() - (int)(RegSize * (NumRegs - Idx));
3399
3400  // Record the frame index of the first variable argument
3401  // which is a value necessary to VASTART.
3402  int FI = MFI->CreateFixedObject(RegSize, VaArgOffset, true);
3403  MipsFI->setVarArgsFrameIndex(FI);
3404
3405  // Copy the integer registers that have not been used for argument passing
3406  // to the argument register save area. For O32, the save area is allocated
3407  // in the caller's stack frame, while for N32/64, it is allocated in the
3408  // callee's stack frame.
3409  for (unsigned I = Idx; I < NumRegs; ++I, VaArgOffset += RegSize) {
3410    unsigned Reg = addLiveIn(MF, ArgRegs[I], RC);
3411    SDValue ArgValue = DAG.getCopyFromReg(Chain, DL, Reg, RegTy);
3412    FI = MFI->CreateFixedObject(RegSize, VaArgOffset, true);
3413    SDValue PtrOff = DAG.getFrameIndex(FI, getPointerTy());
3414    SDValue Store = DAG.getStore(Chain, DL, ArgValue, PtrOff,
3415                                 MachinePointerInfo(), false, false, 0);
3416    cast<StoreSDNode>(Store.getNode())->getMemOperand()->setValue(0);
3417    OutChains.push_back(Store);
3418  }
3419}
3420