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 #include "MipsISelLowering.h"
15 #include "InstPrinter/MipsInstPrinter.h"
16 #include "MCTargetDesc/MipsBaseInfo.h"
17 #include "MipsCCState.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/ADT/StringSwitch.h"
24 #include "llvm/CodeGen/CallingConvLower.h"
25 #include "llvm/CodeGen/MachineFrameInfo.h"
26 #include "llvm/CodeGen/MachineFunction.h"
27 #include "llvm/CodeGen/MachineInstrBuilder.h"
28 #include "llvm/CodeGen/MachineJumpTableInfo.h"
29 #include "llvm/CodeGen/MachineRegisterInfo.h"
30 #include "llvm/CodeGen/FunctionLoweringInfo.h"
31 #include "llvm/CodeGen/SelectionDAGISel.h"
32 #include "llvm/CodeGen/ValueTypes.h"
33 #include "llvm/IR/CallingConv.h"
34 #include "llvm/IR/DerivedTypes.h"
35 #include "llvm/IR/GlobalVariable.h"
36 #include "llvm/Support/CommandLine.h"
37 #include "llvm/Support/Debug.h"
38 #include "llvm/Support/ErrorHandling.h"
39 #include "llvm/Support/raw_ostream.h"
40 #include <cctype>
41 
42 using namespace llvm;
43 
44 #define DEBUG_TYPE "mips-lower"
45 
46 STATISTIC(NumTailCalls, "Number of tail calls");
47 
48 static cl::opt<bool>
49 LargeGOT("mxgot", cl::Hidden,
50          cl::desc("MIPS: Enable GOT larger than 64k."), cl::init(false));
51 
52 static cl::opt<bool>
53 NoZeroDivCheck("mno-check-zero-division", cl::Hidden,
54                cl::desc("MIPS: Don't trap on integer division by zero."),
55                cl::init(false));
56 
57 static const MCPhysReg Mips64DPRegs[8] = {
58   Mips::D12_64, Mips::D13_64, Mips::D14_64, Mips::D15_64,
59   Mips::D16_64, Mips::D17_64, Mips::D18_64, Mips::D19_64
60 };
61 
62 // If I is a shifted mask, set the size (Size) and the first bit of the
63 // mask (Pos), and return true.
64 // For example, if I is 0x003ff800, (Pos, Size) = (11, 11).
isShiftedMask(uint64_t I,uint64_t & Pos,uint64_t & Size)65 static bool isShiftedMask(uint64_t I, uint64_t &Pos, uint64_t &Size) {
66   if (!isShiftedMask_64(I))
67     return false;
68 
69   Size = countPopulation(I);
70   Pos = countTrailingZeros(I);
71   return true;
72 }
73 
getGlobalReg(SelectionDAG & DAG,EVT Ty) const74 SDValue MipsTargetLowering::getGlobalReg(SelectionDAG &DAG, EVT Ty) const {
75   MipsFunctionInfo *FI = DAG.getMachineFunction().getInfo<MipsFunctionInfo>();
76   return DAG.getRegister(FI->getGlobalBaseReg(), Ty);
77 }
78 
getTargetNode(GlobalAddressSDNode * N,EVT Ty,SelectionDAG & DAG,unsigned Flag) const79 SDValue MipsTargetLowering::getTargetNode(GlobalAddressSDNode *N, EVT Ty,
80                                           SelectionDAG &DAG,
81                                           unsigned Flag) const {
82   return DAG.getTargetGlobalAddress(N->getGlobal(), SDLoc(N), Ty, 0, Flag);
83 }
84 
getTargetNode(ExternalSymbolSDNode * N,EVT Ty,SelectionDAG & DAG,unsigned Flag) const85 SDValue MipsTargetLowering::getTargetNode(ExternalSymbolSDNode *N, EVT Ty,
86                                           SelectionDAG &DAG,
87                                           unsigned Flag) const {
88   return DAG.getTargetExternalSymbol(N->getSymbol(), Ty, Flag);
89 }
90 
getTargetNode(BlockAddressSDNode * N,EVT Ty,SelectionDAG & DAG,unsigned Flag) const91 SDValue MipsTargetLowering::getTargetNode(BlockAddressSDNode *N, EVT Ty,
92                                           SelectionDAG &DAG,
93                                           unsigned Flag) const {
94   return DAG.getTargetBlockAddress(N->getBlockAddress(), Ty, 0, Flag);
95 }
96 
getTargetNode(JumpTableSDNode * N,EVT Ty,SelectionDAG & DAG,unsigned Flag) const97 SDValue MipsTargetLowering::getTargetNode(JumpTableSDNode *N, EVT Ty,
98                                           SelectionDAG &DAG,
99                                           unsigned Flag) const {
100   return DAG.getTargetJumpTable(N->getIndex(), Ty, Flag);
101 }
102 
getTargetNode(ConstantPoolSDNode * N,EVT Ty,SelectionDAG & DAG,unsigned Flag) const103 SDValue MipsTargetLowering::getTargetNode(ConstantPoolSDNode *N, EVT Ty,
104                                           SelectionDAG &DAG,
105                                           unsigned Flag) const {
106   return DAG.getTargetConstantPool(N->getConstVal(), Ty, N->getAlignment(),
107                                    N->getOffset(), Flag);
108 }
109 
getTargetNodeName(unsigned Opcode) const110 const char *MipsTargetLowering::getTargetNodeName(unsigned Opcode) const {
111   switch ((MipsISD::NodeType)Opcode) {
112   case MipsISD::FIRST_NUMBER:      break;
113   case MipsISD::JmpLink:           return "MipsISD::JmpLink";
114   case MipsISD::TailCall:          return "MipsISD::TailCall";
115   case MipsISD::Hi:                return "MipsISD::Hi";
116   case MipsISD::Lo:                return "MipsISD::Lo";
117   case MipsISD::GPRel:             return "MipsISD::GPRel";
118   case MipsISD::ThreadPointer:     return "MipsISD::ThreadPointer";
119   case MipsISD::Ret:               return "MipsISD::Ret";
120   case MipsISD::ERet:              return "MipsISD::ERet";
121   case MipsISD::EH_RETURN:         return "MipsISD::EH_RETURN";
122   case MipsISD::FPBrcond:          return "MipsISD::FPBrcond";
123   case MipsISD::FPCmp:             return "MipsISD::FPCmp";
124   case MipsISD::CMovFP_T:          return "MipsISD::CMovFP_T";
125   case MipsISD::CMovFP_F:          return "MipsISD::CMovFP_F";
126   case MipsISD::TruncIntFP:        return "MipsISD::TruncIntFP";
127   case MipsISD::MFHI:              return "MipsISD::MFHI";
128   case MipsISD::MFLO:              return "MipsISD::MFLO";
129   case MipsISD::MTLOHI:            return "MipsISD::MTLOHI";
130   case MipsISD::Mult:              return "MipsISD::Mult";
131   case MipsISD::Multu:             return "MipsISD::Multu";
132   case MipsISD::MAdd:              return "MipsISD::MAdd";
133   case MipsISD::MAddu:             return "MipsISD::MAddu";
134   case MipsISD::MSub:              return "MipsISD::MSub";
135   case MipsISD::MSubu:             return "MipsISD::MSubu";
136   case MipsISD::DivRem:            return "MipsISD::DivRem";
137   case MipsISD::DivRemU:           return "MipsISD::DivRemU";
138   case MipsISD::DivRem16:          return "MipsISD::DivRem16";
139   case MipsISD::DivRemU16:         return "MipsISD::DivRemU16";
140   case MipsISD::BuildPairF64:      return "MipsISD::BuildPairF64";
141   case MipsISD::ExtractElementF64: return "MipsISD::ExtractElementF64";
142   case MipsISD::Wrapper:           return "MipsISD::Wrapper";
143   case MipsISD::DynAlloc:          return "MipsISD::DynAlloc";
144   case MipsISD::Sync:              return "MipsISD::Sync";
145   case MipsISD::Ext:               return "MipsISD::Ext";
146   case MipsISD::Ins:               return "MipsISD::Ins";
147   case MipsISD::LWL:               return "MipsISD::LWL";
148   case MipsISD::LWR:               return "MipsISD::LWR";
149   case MipsISD::SWL:               return "MipsISD::SWL";
150   case MipsISD::SWR:               return "MipsISD::SWR";
151   case MipsISD::LDL:               return "MipsISD::LDL";
152   case MipsISD::LDR:               return "MipsISD::LDR";
153   case MipsISD::SDL:               return "MipsISD::SDL";
154   case MipsISD::SDR:               return "MipsISD::SDR";
155   case MipsISD::EXTP:              return "MipsISD::EXTP";
156   case MipsISD::EXTPDP:            return "MipsISD::EXTPDP";
157   case MipsISD::EXTR_S_H:          return "MipsISD::EXTR_S_H";
158   case MipsISD::EXTR_W:            return "MipsISD::EXTR_W";
159   case MipsISD::EXTR_R_W:          return "MipsISD::EXTR_R_W";
160   case MipsISD::EXTR_RS_W:         return "MipsISD::EXTR_RS_W";
161   case MipsISD::SHILO:             return "MipsISD::SHILO";
162   case MipsISD::MTHLIP:            return "MipsISD::MTHLIP";
163   case MipsISD::MULSAQ_S_W_PH:     return "MipsISD::MULSAQ_S_W_PH";
164   case MipsISD::MAQ_S_W_PHL:       return "MipsISD::MAQ_S_W_PHL";
165   case MipsISD::MAQ_S_W_PHR:       return "MipsISD::MAQ_S_W_PHR";
166   case MipsISD::MAQ_SA_W_PHL:      return "MipsISD::MAQ_SA_W_PHL";
167   case MipsISD::MAQ_SA_W_PHR:      return "MipsISD::MAQ_SA_W_PHR";
168   case MipsISD::DPAU_H_QBL:        return "MipsISD::DPAU_H_QBL";
169   case MipsISD::DPAU_H_QBR:        return "MipsISD::DPAU_H_QBR";
170   case MipsISD::DPSU_H_QBL:        return "MipsISD::DPSU_H_QBL";
171   case MipsISD::DPSU_H_QBR:        return "MipsISD::DPSU_H_QBR";
172   case MipsISD::DPAQ_S_W_PH:       return "MipsISD::DPAQ_S_W_PH";
173   case MipsISD::DPSQ_S_W_PH:       return "MipsISD::DPSQ_S_W_PH";
174   case MipsISD::DPAQ_SA_L_W:       return "MipsISD::DPAQ_SA_L_W";
175   case MipsISD::DPSQ_SA_L_W:       return "MipsISD::DPSQ_SA_L_W";
176   case MipsISD::DPA_W_PH:          return "MipsISD::DPA_W_PH";
177   case MipsISD::DPS_W_PH:          return "MipsISD::DPS_W_PH";
178   case MipsISD::DPAQX_S_W_PH:      return "MipsISD::DPAQX_S_W_PH";
179   case MipsISD::DPAQX_SA_W_PH:     return "MipsISD::DPAQX_SA_W_PH";
180   case MipsISD::DPAX_W_PH:         return "MipsISD::DPAX_W_PH";
181   case MipsISD::DPSX_W_PH:         return "MipsISD::DPSX_W_PH";
182   case MipsISD::DPSQX_S_W_PH:      return "MipsISD::DPSQX_S_W_PH";
183   case MipsISD::DPSQX_SA_W_PH:     return "MipsISD::DPSQX_SA_W_PH";
184   case MipsISD::MULSA_W_PH:        return "MipsISD::MULSA_W_PH";
185   case MipsISD::MULT:              return "MipsISD::MULT";
186   case MipsISD::MULTU:             return "MipsISD::MULTU";
187   case MipsISD::MADD_DSP:          return "MipsISD::MADD_DSP";
188   case MipsISD::MADDU_DSP:         return "MipsISD::MADDU_DSP";
189   case MipsISD::MSUB_DSP:          return "MipsISD::MSUB_DSP";
190   case MipsISD::MSUBU_DSP:         return "MipsISD::MSUBU_DSP";
191   case MipsISD::SHLL_DSP:          return "MipsISD::SHLL_DSP";
192   case MipsISD::SHRA_DSP:          return "MipsISD::SHRA_DSP";
193   case MipsISD::SHRL_DSP:          return "MipsISD::SHRL_DSP";
194   case MipsISD::SETCC_DSP:         return "MipsISD::SETCC_DSP";
195   case MipsISD::SELECT_CC_DSP:     return "MipsISD::SELECT_CC_DSP";
196   case MipsISD::VALL_ZERO:         return "MipsISD::VALL_ZERO";
197   case MipsISD::VANY_ZERO:         return "MipsISD::VANY_ZERO";
198   case MipsISD::VALL_NONZERO:      return "MipsISD::VALL_NONZERO";
199   case MipsISD::VANY_NONZERO:      return "MipsISD::VANY_NONZERO";
200   case MipsISD::VCEQ:              return "MipsISD::VCEQ";
201   case MipsISD::VCLE_S:            return "MipsISD::VCLE_S";
202   case MipsISD::VCLE_U:            return "MipsISD::VCLE_U";
203   case MipsISD::VCLT_S:            return "MipsISD::VCLT_S";
204   case MipsISD::VCLT_U:            return "MipsISD::VCLT_U";
205   case MipsISD::VSMAX:             return "MipsISD::VSMAX";
206   case MipsISD::VSMIN:             return "MipsISD::VSMIN";
207   case MipsISD::VUMAX:             return "MipsISD::VUMAX";
208   case MipsISD::VUMIN:             return "MipsISD::VUMIN";
209   case MipsISD::VEXTRACT_SEXT_ELT: return "MipsISD::VEXTRACT_SEXT_ELT";
210   case MipsISD::VEXTRACT_ZEXT_ELT: return "MipsISD::VEXTRACT_ZEXT_ELT";
211   case MipsISD::VNOR:              return "MipsISD::VNOR";
212   case MipsISD::VSHF:              return "MipsISD::VSHF";
213   case MipsISD::SHF:               return "MipsISD::SHF";
214   case MipsISD::ILVEV:             return "MipsISD::ILVEV";
215   case MipsISD::ILVOD:             return "MipsISD::ILVOD";
216   case MipsISD::ILVL:              return "MipsISD::ILVL";
217   case MipsISD::ILVR:              return "MipsISD::ILVR";
218   case MipsISD::PCKEV:             return "MipsISD::PCKEV";
219   case MipsISD::PCKOD:             return "MipsISD::PCKOD";
220   case MipsISD::INSVE:             return "MipsISD::INSVE";
221   }
222   return nullptr;
223 }
224 
MipsTargetLowering(const MipsTargetMachine & TM,const MipsSubtarget & STI)225 MipsTargetLowering::MipsTargetLowering(const MipsTargetMachine &TM,
226                                        const MipsSubtarget &STI)
227     : TargetLowering(TM), Subtarget(STI), ABI(TM.getABI()) {
228   // Mips does not have i1 type, so use i32 for
229   // setcc operations results (slt, sgt, ...).
230   setBooleanContents(ZeroOrOneBooleanContent);
231   setBooleanVectorContents(ZeroOrNegativeOneBooleanContent);
232   // The cmp.cond.fmt instruction in MIPS32r6/MIPS64r6 uses 0 and -1 like MSA
233   // does. Integer booleans still use 0 and 1.
234   if (Subtarget.hasMips32r6())
235     setBooleanContents(ZeroOrOneBooleanContent,
236                        ZeroOrNegativeOneBooleanContent);
237 
238   // Load extented operations for i1 types must be promoted
239   for (MVT VT : MVT::integer_valuetypes()) {
240     setLoadExtAction(ISD::EXTLOAD,  VT, MVT::i1,  Promote);
241     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i1,  Promote);
242     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i1,  Promote);
243   }
244 
245   // MIPS doesn't have extending float->double load/store.  Set LoadExtAction
246   // for f32, f16
247   for (MVT VT : MVT::fp_valuetypes()) {
248     setLoadExtAction(ISD::EXTLOAD, VT, MVT::f32, Expand);
249     setLoadExtAction(ISD::EXTLOAD, VT, MVT::f16, Expand);
250   }
251 
252   // Set LoadExtAction for f16 vectors to Expand
253   for (MVT VT : MVT::fp_vector_valuetypes()) {
254     MVT F16VT = MVT::getVectorVT(MVT::f16, VT.getVectorNumElements());
255     if (F16VT.isValid())
256       setLoadExtAction(ISD::EXTLOAD, VT, F16VT, Expand);
257   }
258 
259   setTruncStoreAction(MVT::f32, MVT::f16, Expand);
260   setTruncStoreAction(MVT::f64, MVT::f16, Expand);
261 
262   setTruncStoreAction(MVT::f64, MVT::f32, Expand);
263 
264   // Used by legalize types to correctly generate the setcc result.
265   // Without this, every float setcc comes with a AND/OR with the result,
266   // we don't want this, since the fpcmp result goes to a flag register,
267   // which is used implicitly by brcond and select operations.
268   AddPromotedToType(ISD::SETCC, MVT::i1, MVT::i32);
269 
270   // Mips Custom Operations
271   setOperationAction(ISD::BR_JT,              MVT::Other, Custom);
272   setOperationAction(ISD::GlobalAddress,      MVT::i32,   Custom);
273   setOperationAction(ISD::BlockAddress,       MVT::i32,   Custom);
274   setOperationAction(ISD::GlobalTLSAddress,   MVT::i32,   Custom);
275   setOperationAction(ISD::JumpTable,          MVT::i32,   Custom);
276   setOperationAction(ISD::ConstantPool,       MVT::i32,   Custom);
277   setOperationAction(ISD::SELECT,             MVT::f32,   Custom);
278   setOperationAction(ISD::SELECT,             MVT::f64,   Custom);
279   setOperationAction(ISD::SELECT,             MVT::i32,   Custom);
280   setOperationAction(ISD::SELECT_CC,          MVT::f32,   Custom);
281   setOperationAction(ISD::SELECT_CC,          MVT::f64,   Custom);
282   setOperationAction(ISD::SETCC,              MVT::f32,   Custom);
283   setOperationAction(ISD::SETCC,              MVT::f64,   Custom);
284   setOperationAction(ISD::BRCOND,             MVT::Other, Custom);
285   setOperationAction(ISD::FCOPYSIGN,          MVT::f32,   Custom);
286   setOperationAction(ISD::FCOPYSIGN,          MVT::f64,   Custom);
287   setOperationAction(ISD::FP_TO_SINT,         MVT::i32,   Custom);
288 
289   if (Subtarget.isGP64bit()) {
290     setOperationAction(ISD::GlobalAddress,      MVT::i64,   Custom);
291     setOperationAction(ISD::BlockAddress,       MVT::i64,   Custom);
292     setOperationAction(ISD::GlobalTLSAddress,   MVT::i64,   Custom);
293     setOperationAction(ISD::JumpTable,          MVT::i64,   Custom);
294     setOperationAction(ISD::ConstantPool,       MVT::i64,   Custom);
295     setOperationAction(ISD::SELECT,             MVT::i64,   Custom);
296     setOperationAction(ISD::LOAD,               MVT::i64,   Custom);
297     setOperationAction(ISD::STORE,              MVT::i64,   Custom);
298     setOperationAction(ISD::FP_TO_SINT,         MVT::i64,   Custom);
299     setOperationAction(ISD::SHL_PARTS,          MVT::i64,   Custom);
300     setOperationAction(ISD::SRA_PARTS,          MVT::i64,   Custom);
301     setOperationAction(ISD::SRL_PARTS,          MVT::i64,   Custom);
302   }
303 
304   if (!Subtarget.isGP64bit()) {
305     setOperationAction(ISD::SHL_PARTS,          MVT::i32,   Custom);
306     setOperationAction(ISD::SRA_PARTS,          MVT::i32,   Custom);
307     setOperationAction(ISD::SRL_PARTS,          MVT::i32,   Custom);
308   }
309 
310   setOperationAction(ISD::ADD,                MVT::i32,   Custom);
311   if (Subtarget.isGP64bit())
312     setOperationAction(ISD::ADD,                MVT::i64,   Custom);
313 
314   setOperationAction(ISD::SDIV, MVT::i32, Expand);
315   setOperationAction(ISD::SREM, MVT::i32, Expand);
316   setOperationAction(ISD::UDIV, MVT::i32, Expand);
317   setOperationAction(ISD::UREM, MVT::i32, Expand);
318   setOperationAction(ISD::SDIV, MVT::i64, Expand);
319   setOperationAction(ISD::SREM, MVT::i64, Expand);
320   setOperationAction(ISD::UDIV, MVT::i64, Expand);
321   setOperationAction(ISD::UREM, MVT::i64, Expand);
322 
323   // Operations not directly supported by Mips.
324   setOperationAction(ISD::BR_CC,             MVT::f32,   Expand);
325   setOperationAction(ISD::BR_CC,             MVT::f64,   Expand);
326   setOperationAction(ISD::BR_CC,             MVT::i32,   Expand);
327   setOperationAction(ISD::BR_CC,             MVT::i64,   Expand);
328   setOperationAction(ISD::SELECT_CC,         MVT::i32,   Expand);
329   setOperationAction(ISD::SELECT_CC,         MVT::i64,   Expand);
330   setOperationAction(ISD::UINT_TO_FP,        MVT::i32,   Expand);
331   setOperationAction(ISD::UINT_TO_FP,        MVT::i64,   Expand);
332   setOperationAction(ISD::FP_TO_UINT,        MVT::i32,   Expand);
333   setOperationAction(ISD::FP_TO_UINT,        MVT::i64,   Expand);
334   setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i1,    Expand);
335   if (Subtarget.hasCnMips()) {
336     setOperationAction(ISD::CTPOP,           MVT::i32,   Legal);
337     setOperationAction(ISD::CTPOP,           MVT::i64,   Legal);
338   } else {
339     setOperationAction(ISD::CTPOP,           MVT::i32,   Expand);
340     setOperationAction(ISD::CTPOP,           MVT::i64,   Expand);
341   }
342   setOperationAction(ISD::CTTZ,              MVT::i32,   Expand);
343   setOperationAction(ISD::CTTZ,              MVT::i64,   Expand);
344   setOperationAction(ISD::CTTZ_ZERO_UNDEF,   MVT::i32,   Expand);
345   setOperationAction(ISD::CTTZ_ZERO_UNDEF,   MVT::i64,   Expand);
346   setOperationAction(ISD::CTLZ_ZERO_UNDEF,   MVT::i32,   Expand);
347   setOperationAction(ISD::CTLZ_ZERO_UNDEF,   MVT::i64,   Expand);
348   setOperationAction(ISD::ROTL,              MVT::i32,   Expand);
349   setOperationAction(ISD::ROTL,              MVT::i64,   Expand);
350   setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32,  Expand);
351   setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i64,  Expand);
352 
353   if (!Subtarget.hasMips32r2())
354     setOperationAction(ISD::ROTR, MVT::i32,   Expand);
355 
356   if (!Subtarget.hasMips64r2())
357     setOperationAction(ISD::ROTR, MVT::i64,   Expand);
358 
359   setOperationAction(ISD::FSIN,              MVT::f32,   Expand);
360   setOperationAction(ISD::FSIN,              MVT::f64,   Expand);
361   setOperationAction(ISD::FCOS,              MVT::f32,   Expand);
362   setOperationAction(ISD::FCOS,              MVT::f64,   Expand);
363   setOperationAction(ISD::FSINCOS,           MVT::f32,   Expand);
364   setOperationAction(ISD::FSINCOS,           MVT::f64,   Expand);
365   setOperationAction(ISD::FPOWI,             MVT::f32,   Expand);
366   setOperationAction(ISD::FPOW,              MVT::f32,   Expand);
367   setOperationAction(ISD::FPOW,              MVT::f64,   Expand);
368   setOperationAction(ISD::FLOG,              MVT::f32,   Expand);
369   setOperationAction(ISD::FLOG2,             MVT::f32,   Expand);
370   setOperationAction(ISD::FLOG10,            MVT::f32,   Expand);
371   setOperationAction(ISD::FEXP,              MVT::f32,   Expand);
372   setOperationAction(ISD::FMA,               MVT::f32,   Expand);
373   setOperationAction(ISD::FMA,               MVT::f64,   Expand);
374   setOperationAction(ISD::FREM,              MVT::f32,   Expand);
375   setOperationAction(ISD::FREM,              MVT::f64,   Expand);
376 
377   // Lower f16 conversion operations into library calls
378   setOperationAction(ISD::FP16_TO_FP,        MVT::f32,   Expand);
379   setOperationAction(ISD::FP_TO_FP16,        MVT::f32,   Expand);
380   setOperationAction(ISD::FP16_TO_FP,        MVT::f64,   Expand);
381   setOperationAction(ISD::FP_TO_FP16,        MVT::f64,   Expand);
382 
383   setOperationAction(ISD::EH_RETURN, MVT::Other, Custom);
384 
385   setOperationAction(ISD::VASTART,           MVT::Other, Custom);
386   setOperationAction(ISD::VAARG,             MVT::Other, Custom);
387   setOperationAction(ISD::VACOPY,            MVT::Other, Expand);
388   setOperationAction(ISD::VAEND,             MVT::Other, Expand);
389 
390   // Use the default for now
391   setOperationAction(ISD::STACKSAVE,         MVT::Other, Expand);
392   setOperationAction(ISD::STACKRESTORE,      MVT::Other, Expand);
393 
394   if (!Subtarget.isGP64bit()) {
395     setOperationAction(ISD::ATOMIC_LOAD,     MVT::i64,   Expand);
396     setOperationAction(ISD::ATOMIC_STORE,    MVT::i64,   Expand);
397   }
398 
399   setInsertFencesForAtomic(true);
400 
401   if (!Subtarget.hasMips32r2()) {
402     setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i8,  Expand);
403     setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i16, Expand);
404   }
405 
406   // MIPS16 lacks MIPS32's clz and clo instructions.
407   if (!Subtarget.hasMips32() || Subtarget.inMips16Mode())
408     setOperationAction(ISD::CTLZ, MVT::i32, Expand);
409   if (!Subtarget.hasMips64())
410     setOperationAction(ISD::CTLZ, MVT::i64, Expand);
411 
412   if (!Subtarget.hasMips32r2())
413     setOperationAction(ISD::BSWAP, MVT::i32, Expand);
414   if (!Subtarget.hasMips64r2())
415     setOperationAction(ISD::BSWAP, MVT::i64, Expand);
416 
417   if (Subtarget.isGP64bit()) {
418     setLoadExtAction(ISD::SEXTLOAD, MVT::i64, MVT::i32, Custom);
419     setLoadExtAction(ISD::ZEXTLOAD, MVT::i64, MVT::i32, Custom);
420     setLoadExtAction(ISD::EXTLOAD, MVT::i64, MVT::i32, Custom);
421     setTruncStoreAction(MVT::i64, MVT::i32, Custom);
422   }
423 
424   setOperationAction(ISD::TRAP, MVT::Other, Legal);
425 
426   setTargetDAGCombine(ISD::SDIVREM);
427   setTargetDAGCombine(ISD::UDIVREM);
428   setTargetDAGCombine(ISD::SELECT);
429   setTargetDAGCombine(ISD::AND);
430   setTargetDAGCombine(ISD::OR);
431   setTargetDAGCombine(ISD::ADD);
432 
433   setMinFunctionAlignment(Subtarget.isGP64bit() ? 3 : 2);
434 
435   // The arguments on the stack are defined in terms of 4-byte slots on O32
436   // and 8-byte slots on N32/N64.
437   setMinStackArgumentAlignment((ABI.IsN32() || ABI.IsN64()) ? 8 : 4);
438 
439   setStackPointerRegisterToSaveRestore(ABI.IsN64() ? Mips::SP_64 : Mips::SP);
440 
441   MaxStoresPerMemcpy = 16;
442 
443   isMicroMips = Subtarget.inMicroMipsMode();
444 }
445 
create(const MipsTargetMachine & TM,const MipsSubtarget & STI)446 const MipsTargetLowering *MipsTargetLowering::create(const MipsTargetMachine &TM,
447                                                      const MipsSubtarget &STI) {
448   if (STI.inMips16Mode())
449     return llvm::createMips16TargetLowering(TM, STI);
450 
451   return llvm::createMipsSETargetLowering(TM, STI);
452 }
453 
454 // Create a fast isel object.
455 FastISel *
createFastISel(FunctionLoweringInfo & funcInfo,const TargetLibraryInfo * libInfo) const456 MipsTargetLowering::createFastISel(FunctionLoweringInfo &funcInfo,
457                                   const TargetLibraryInfo *libInfo) const {
458   if (!funcInfo.MF->getTarget().Options.EnableFastISel)
459     return TargetLowering::createFastISel(funcInfo, libInfo);
460   return Mips::createFastISel(funcInfo, libInfo);
461 }
462 
getSetCCResultType(const DataLayout &,LLVMContext &,EVT VT) const463 EVT MipsTargetLowering::getSetCCResultType(const DataLayout &, LLVMContext &,
464                                            EVT VT) const {
465   if (!VT.isVector())
466     return MVT::i32;
467   return VT.changeVectorElementTypeToInteger();
468 }
469 
performDivRemCombine(SDNode * N,SelectionDAG & DAG,TargetLowering::DAGCombinerInfo & DCI,const MipsSubtarget & Subtarget)470 static SDValue performDivRemCombine(SDNode *N, SelectionDAG &DAG,
471                                     TargetLowering::DAGCombinerInfo &DCI,
472                                     const MipsSubtarget &Subtarget) {
473   if (DCI.isBeforeLegalizeOps())
474     return SDValue();
475 
476   EVT Ty = N->getValueType(0);
477   unsigned LO = (Ty == MVT::i32) ? Mips::LO0 : Mips::LO0_64;
478   unsigned HI = (Ty == MVT::i32) ? Mips::HI0 : Mips::HI0_64;
479   unsigned Opc = N->getOpcode() == ISD::SDIVREM ? MipsISD::DivRem16 :
480                                                   MipsISD::DivRemU16;
481   SDLoc DL(N);
482 
483   SDValue DivRem = DAG.getNode(Opc, DL, MVT::Glue,
484                                N->getOperand(0), N->getOperand(1));
485   SDValue InChain = DAG.getEntryNode();
486   SDValue InGlue = DivRem;
487 
488   // insert MFLO
489   if (N->hasAnyUseOfValue(0)) {
490     SDValue CopyFromLo = DAG.getCopyFromReg(InChain, DL, LO, Ty,
491                                             InGlue);
492     DAG.ReplaceAllUsesOfValueWith(SDValue(N, 0), CopyFromLo);
493     InChain = CopyFromLo.getValue(1);
494     InGlue = CopyFromLo.getValue(2);
495   }
496 
497   // insert MFHI
498   if (N->hasAnyUseOfValue(1)) {
499     SDValue CopyFromHi = DAG.getCopyFromReg(InChain, DL,
500                                             HI, Ty, InGlue);
501     DAG.ReplaceAllUsesOfValueWith(SDValue(N, 1), CopyFromHi);
502   }
503 
504   return SDValue();
505 }
506 
condCodeToFCC(ISD::CondCode CC)507 static Mips::CondCode condCodeToFCC(ISD::CondCode CC) {
508   switch (CC) {
509   default: llvm_unreachable("Unknown fp condition code!");
510   case ISD::SETEQ:
511   case ISD::SETOEQ: return Mips::FCOND_OEQ;
512   case ISD::SETUNE: return Mips::FCOND_UNE;
513   case ISD::SETLT:
514   case ISD::SETOLT: return Mips::FCOND_OLT;
515   case ISD::SETGT:
516   case ISD::SETOGT: return Mips::FCOND_OGT;
517   case ISD::SETLE:
518   case ISD::SETOLE: return Mips::FCOND_OLE;
519   case ISD::SETGE:
520   case ISD::SETOGE: return Mips::FCOND_OGE;
521   case ISD::SETULT: return Mips::FCOND_ULT;
522   case ISD::SETULE: return Mips::FCOND_ULE;
523   case ISD::SETUGT: return Mips::FCOND_UGT;
524   case ISD::SETUGE: return Mips::FCOND_UGE;
525   case ISD::SETUO:  return Mips::FCOND_UN;
526   case ISD::SETO:   return Mips::FCOND_OR;
527   case ISD::SETNE:
528   case ISD::SETONE: return Mips::FCOND_ONE;
529   case ISD::SETUEQ: return Mips::FCOND_UEQ;
530   }
531 }
532 
533 
534 /// This function returns true if the floating point conditional branches and
535 /// conditional moves which use condition code CC should be inverted.
invertFPCondCodeUser(Mips::CondCode CC)536 static bool invertFPCondCodeUser(Mips::CondCode CC) {
537   if (CC >= Mips::FCOND_F && CC <= Mips::FCOND_NGT)
538     return false;
539 
540   assert((CC >= Mips::FCOND_T && CC <= Mips::FCOND_GT) &&
541          "Illegal Condition Code");
542 
543   return true;
544 }
545 
546 // Creates and returns an FPCmp node from a setcc node.
547 // Returns Op if setcc is not a floating point comparison.
createFPCmp(SelectionDAG & DAG,const SDValue & Op)548 static SDValue createFPCmp(SelectionDAG &DAG, const SDValue &Op) {
549   // must be a SETCC node
550   if (Op.getOpcode() != ISD::SETCC)
551     return Op;
552 
553   SDValue LHS = Op.getOperand(0);
554 
555   if (!LHS.getValueType().isFloatingPoint())
556     return Op;
557 
558   SDValue RHS = Op.getOperand(1);
559   SDLoc DL(Op);
560 
561   // Assume the 3rd operand is a CondCodeSDNode. Add code to check the type of
562   // node if necessary.
563   ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(2))->get();
564 
565   return DAG.getNode(MipsISD::FPCmp, DL, MVT::Glue, LHS, RHS,
566                      DAG.getConstant(condCodeToFCC(CC), DL, MVT::i32));
567 }
568 
569 // Creates and returns a CMovFPT/F node.
createCMovFP(SelectionDAG & DAG,SDValue Cond,SDValue True,SDValue False,SDLoc DL)570 static SDValue createCMovFP(SelectionDAG &DAG, SDValue Cond, SDValue True,
571                             SDValue False, SDLoc DL) {
572   ConstantSDNode *CC = cast<ConstantSDNode>(Cond.getOperand(2));
573   bool invert = invertFPCondCodeUser((Mips::CondCode)CC->getSExtValue());
574   SDValue FCC0 = DAG.getRegister(Mips::FCC0, MVT::i32);
575 
576   return DAG.getNode((invert ? MipsISD::CMovFP_F : MipsISD::CMovFP_T), DL,
577                      True.getValueType(), True, FCC0, False, Cond);
578 }
579 
performSELECTCombine(SDNode * N,SelectionDAG & DAG,TargetLowering::DAGCombinerInfo & DCI,const MipsSubtarget & Subtarget)580 static SDValue performSELECTCombine(SDNode *N, SelectionDAG &DAG,
581                                     TargetLowering::DAGCombinerInfo &DCI,
582                                     const MipsSubtarget &Subtarget) {
583   if (DCI.isBeforeLegalizeOps())
584     return SDValue();
585 
586   SDValue SetCC = N->getOperand(0);
587 
588   if ((SetCC.getOpcode() != ISD::SETCC) ||
589       !SetCC.getOperand(0).getValueType().isInteger())
590     return SDValue();
591 
592   SDValue False = N->getOperand(2);
593   EVT FalseTy = False.getValueType();
594 
595   if (!FalseTy.isInteger())
596     return SDValue();
597 
598   ConstantSDNode *FalseC = dyn_cast<ConstantSDNode>(False);
599 
600   // If the RHS (False) is 0, we swap the order of the operands
601   // of ISD::SELECT (obviously also inverting the condition) so that we can
602   // take advantage of conditional moves using the $0 register.
603   // Example:
604   //   return (a != 0) ? x : 0;
605   //     load $reg, x
606   //     movz $reg, $0, a
607   if (!FalseC)
608     return SDValue();
609 
610   const SDLoc DL(N);
611 
612   if (!FalseC->getZExtValue()) {
613     ISD::CondCode CC = cast<CondCodeSDNode>(SetCC.getOperand(2))->get();
614     SDValue True = N->getOperand(1);
615 
616     SetCC = DAG.getSetCC(DL, SetCC.getValueType(), SetCC.getOperand(0),
617                          SetCC.getOperand(1), ISD::getSetCCInverse(CC, true));
618 
619     return DAG.getNode(ISD::SELECT, DL, FalseTy, SetCC, False, True);
620   }
621 
622   // If both operands are integer constants there's a possibility that we
623   // can do some interesting optimizations.
624   SDValue True = N->getOperand(1);
625   ConstantSDNode *TrueC = dyn_cast<ConstantSDNode>(True);
626 
627   if (!TrueC || !True.getValueType().isInteger())
628     return SDValue();
629 
630   // We'll also ignore MVT::i64 operands as this optimizations proves
631   // to be ineffective because of the required sign extensions as the result
632   // of a SETCC operator is always MVT::i32 for non-vector types.
633   if (True.getValueType() == MVT::i64)
634     return SDValue();
635 
636   int64_t Diff = TrueC->getSExtValue() - FalseC->getSExtValue();
637 
638   // 1)  (a < x) ? y : y-1
639   //  slti $reg1, a, x
640   //  addiu $reg2, $reg1, y-1
641   if (Diff == 1)
642     return DAG.getNode(ISD::ADD, DL, SetCC.getValueType(), SetCC, False);
643 
644   // 2)  (a < x) ? y-1 : y
645   //  slti $reg1, a, x
646   //  xor $reg1, $reg1, 1
647   //  addiu $reg2, $reg1, y-1
648   if (Diff == -1) {
649     ISD::CondCode CC = cast<CondCodeSDNode>(SetCC.getOperand(2))->get();
650     SetCC = DAG.getSetCC(DL, SetCC.getValueType(), SetCC.getOperand(0),
651                          SetCC.getOperand(1), ISD::getSetCCInverse(CC, true));
652     return DAG.getNode(ISD::ADD, DL, SetCC.getValueType(), SetCC, True);
653   }
654 
655   // Couldn't optimize.
656   return SDValue();
657 }
658 
performCMovFPCombine(SDNode * N,SelectionDAG & DAG,TargetLowering::DAGCombinerInfo & DCI,const MipsSubtarget & Subtarget)659 static SDValue performCMovFPCombine(SDNode *N, SelectionDAG &DAG,
660                                     TargetLowering::DAGCombinerInfo &DCI,
661                                     const MipsSubtarget &Subtarget) {
662   if (DCI.isBeforeLegalizeOps())
663     return SDValue();
664 
665   SDValue ValueIfTrue = N->getOperand(0), ValueIfFalse = N->getOperand(2);
666 
667   ConstantSDNode *FalseC = dyn_cast<ConstantSDNode>(ValueIfFalse);
668   if (!FalseC || FalseC->getZExtValue())
669     return SDValue();
670 
671   // Since RHS (False) is 0, we swap the order of the True/False operands
672   // (obviously also inverting the condition) so that we can
673   // take advantage of conditional moves using the $0 register.
674   // Example:
675   //   return (a != 0) ? x : 0;
676   //     load $reg, x
677   //     movz $reg, $0, a
678   unsigned Opc = (N->getOpcode() == MipsISD::CMovFP_T) ? MipsISD::CMovFP_F :
679                                                          MipsISD::CMovFP_T;
680 
681   SDValue FCC = N->getOperand(1), Glue = N->getOperand(3);
682   return DAG.getNode(Opc, SDLoc(N), ValueIfFalse.getValueType(),
683                      ValueIfFalse, FCC, ValueIfTrue, Glue);
684 }
685 
performANDCombine(SDNode * N,SelectionDAG & DAG,TargetLowering::DAGCombinerInfo & DCI,const MipsSubtarget & Subtarget)686 static SDValue performANDCombine(SDNode *N, SelectionDAG &DAG,
687                                  TargetLowering::DAGCombinerInfo &DCI,
688                                  const MipsSubtarget &Subtarget) {
689   // Pattern match EXT.
690   //  $dst = and ((sra or srl) $src , pos), (2**size - 1)
691   //  => ext $dst, $src, size, pos
692   if (DCI.isBeforeLegalizeOps() || !Subtarget.hasExtractInsert())
693     return SDValue();
694 
695   SDValue ShiftRight = N->getOperand(0), Mask = N->getOperand(1);
696   unsigned ShiftRightOpc = ShiftRight.getOpcode();
697 
698   // Op's first operand must be a shift right.
699   if (ShiftRightOpc != ISD::SRA && ShiftRightOpc != ISD::SRL)
700     return SDValue();
701 
702   // The second operand of the shift must be an immediate.
703   ConstantSDNode *CN;
704   if (!(CN = dyn_cast<ConstantSDNode>(ShiftRight.getOperand(1))))
705     return SDValue();
706 
707   uint64_t Pos = CN->getZExtValue();
708   uint64_t SMPos, SMSize;
709 
710   // Op's second operand must be a shifted mask.
711   if (!(CN = dyn_cast<ConstantSDNode>(Mask)) ||
712       !isShiftedMask(CN->getZExtValue(), SMPos, SMSize))
713     return SDValue();
714 
715   // Return if the shifted mask does not start at bit 0 or the sum of its size
716   // and Pos exceeds the word's size.
717   EVT ValTy = N->getValueType(0);
718   if (SMPos != 0 || Pos + SMSize > ValTy.getSizeInBits())
719     return SDValue();
720 
721   SDLoc DL(N);
722   return DAG.getNode(MipsISD::Ext, DL, ValTy,
723                      ShiftRight.getOperand(0),
724                      DAG.getConstant(Pos, DL, MVT::i32),
725                      DAG.getConstant(SMSize, DL, MVT::i32));
726 }
727 
performORCombine(SDNode * N,SelectionDAG & DAG,TargetLowering::DAGCombinerInfo & DCI,const MipsSubtarget & Subtarget)728 static SDValue performORCombine(SDNode *N, SelectionDAG &DAG,
729                                 TargetLowering::DAGCombinerInfo &DCI,
730                                 const MipsSubtarget &Subtarget) {
731   // Pattern match INS.
732   //  $dst = or (and $src1 , mask0), (and (shl $src, pos), mask1),
733   //  where mask1 = (2**size - 1) << pos, mask0 = ~mask1
734   //  => ins $dst, $src, size, pos, $src1
735   if (DCI.isBeforeLegalizeOps() || !Subtarget.hasExtractInsert())
736     return SDValue();
737 
738   SDValue And0 = N->getOperand(0), And1 = N->getOperand(1);
739   uint64_t SMPos0, SMSize0, SMPos1, SMSize1;
740   ConstantSDNode *CN;
741 
742   // See if Op's first operand matches (and $src1 , mask0).
743   if (And0.getOpcode() != ISD::AND)
744     return SDValue();
745 
746   if (!(CN = dyn_cast<ConstantSDNode>(And0.getOperand(1))) ||
747       !isShiftedMask(~CN->getSExtValue(), SMPos0, SMSize0))
748     return SDValue();
749 
750   // See if Op's second operand matches (and (shl $src, pos), mask1).
751   if (And1.getOpcode() != ISD::AND)
752     return SDValue();
753 
754   if (!(CN = dyn_cast<ConstantSDNode>(And1.getOperand(1))) ||
755       !isShiftedMask(CN->getZExtValue(), SMPos1, SMSize1))
756     return SDValue();
757 
758   // The shift masks must have the same position and size.
759   if (SMPos0 != SMPos1 || SMSize0 != SMSize1)
760     return SDValue();
761 
762   SDValue Shl = And1.getOperand(0);
763   if (Shl.getOpcode() != ISD::SHL)
764     return SDValue();
765 
766   if (!(CN = dyn_cast<ConstantSDNode>(Shl.getOperand(1))))
767     return SDValue();
768 
769   unsigned Shamt = CN->getZExtValue();
770 
771   // Return if the shift amount and the first bit position of mask are not the
772   // same.
773   EVT ValTy = N->getValueType(0);
774   if ((Shamt != SMPos0) || (SMPos0 + SMSize0 > ValTy.getSizeInBits()))
775     return SDValue();
776 
777   SDLoc DL(N);
778   return DAG.getNode(MipsISD::Ins, DL, ValTy, Shl.getOperand(0),
779                      DAG.getConstant(SMPos0, DL, MVT::i32),
780                      DAG.getConstant(SMSize0, DL, MVT::i32),
781                      And0.getOperand(0));
782 }
783 
performADDCombine(SDNode * N,SelectionDAG & DAG,TargetLowering::DAGCombinerInfo & DCI,const MipsSubtarget & Subtarget)784 static SDValue performADDCombine(SDNode *N, SelectionDAG &DAG,
785                                  TargetLowering::DAGCombinerInfo &DCI,
786                                  const MipsSubtarget &Subtarget) {
787   // (add v0, (add v1, abs_lo(tjt))) => (add (add v0, v1), abs_lo(tjt))
788 
789   if (DCI.isBeforeLegalizeOps())
790     return SDValue();
791 
792   SDValue Add = N->getOperand(1);
793 
794   if (Add.getOpcode() != ISD::ADD)
795     return SDValue();
796 
797   SDValue Lo = Add.getOperand(1);
798 
799   if ((Lo.getOpcode() != MipsISD::Lo) ||
800       (Lo.getOperand(0).getOpcode() != ISD::TargetJumpTable))
801     return SDValue();
802 
803   EVT ValTy = N->getValueType(0);
804   SDLoc DL(N);
805 
806   SDValue Add1 = DAG.getNode(ISD::ADD, DL, ValTy, N->getOperand(0),
807                              Add.getOperand(0));
808   return DAG.getNode(ISD::ADD, DL, ValTy, Add1, Lo);
809 }
810 
PerformDAGCombine(SDNode * N,DAGCombinerInfo & DCI) const811 SDValue  MipsTargetLowering::PerformDAGCombine(SDNode *N, DAGCombinerInfo &DCI)
812   const {
813   SelectionDAG &DAG = DCI.DAG;
814   unsigned Opc = N->getOpcode();
815 
816   switch (Opc) {
817   default: break;
818   case ISD::SDIVREM:
819   case ISD::UDIVREM:
820     return performDivRemCombine(N, DAG, DCI, Subtarget);
821   case ISD::SELECT:
822     return performSELECTCombine(N, DAG, DCI, Subtarget);
823   case MipsISD::CMovFP_F:
824   case MipsISD::CMovFP_T:
825     return performCMovFPCombine(N, DAG, DCI, Subtarget);
826   case ISD::AND:
827     return performANDCombine(N, DAG, DCI, Subtarget);
828   case ISD::OR:
829     return performORCombine(N, DAG, DCI, Subtarget);
830   case ISD::ADD:
831     return performADDCombine(N, DAG, DCI, Subtarget);
832   }
833 
834   return SDValue();
835 }
836 
isCheapToSpeculateCttz() const837 bool MipsTargetLowering::isCheapToSpeculateCttz() const {
838   return Subtarget.hasMips32();
839 }
840 
isCheapToSpeculateCtlz() const841 bool MipsTargetLowering::isCheapToSpeculateCtlz() const {
842   return Subtarget.hasMips32();
843 }
844 
845 void
LowerOperationWrapper(SDNode * N,SmallVectorImpl<SDValue> & Results,SelectionDAG & DAG) const846 MipsTargetLowering::LowerOperationWrapper(SDNode *N,
847                                           SmallVectorImpl<SDValue> &Results,
848                                           SelectionDAG &DAG) const {
849   SDValue Res = LowerOperation(SDValue(N, 0), DAG);
850 
851   for (unsigned I = 0, E = Res->getNumValues(); I != E; ++I)
852     Results.push_back(Res.getValue(I));
853 }
854 
855 void
ReplaceNodeResults(SDNode * N,SmallVectorImpl<SDValue> & Results,SelectionDAG & DAG) const856 MipsTargetLowering::ReplaceNodeResults(SDNode *N,
857                                        SmallVectorImpl<SDValue> &Results,
858                                        SelectionDAG &DAG) const {
859   return LowerOperationWrapper(N, Results, DAG);
860 }
861 
862 SDValue MipsTargetLowering::
LowerOperation(SDValue Op,SelectionDAG & DAG) const863 LowerOperation(SDValue Op, SelectionDAG &DAG) const
864 {
865   switch (Op.getOpcode())
866   {
867   case ISD::BR_JT:              return lowerBR_JT(Op, DAG);
868   case ISD::BRCOND:             return lowerBRCOND(Op, DAG);
869   case ISD::ConstantPool:       return lowerConstantPool(Op, DAG);
870   case ISD::GlobalAddress:      return lowerGlobalAddress(Op, DAG);
871   case ISD::BlockAddress:       return lowerBlockAddress(Op, DAG);
872   case ISD::GlobalTLSAddress:   return lowerGlobalTLSAddress(Op, DAG);
873   case ISD::JumpTable:          return lowerJumpTable(Op, DAG);
874   case ISD::SELECT:             return lowerSELECT(Op, DAG);
875   case ISD::SELECT_CC:          return lowerSELECT_CC(Op, DAG);
876   case ISD::SETCC:              return lowerSETCC(Op, DAG);
877   case ISD::VASTART:            return lowerVASTART(Op, DAG);
878   case ISD::VAARG:              return lowerVAARG(Op, DAG);
879   case ISD::FCOPYSIGN:          return lowerFCOPYSIGN(Op, DAG);
880   case ISD::FRAMEADDR:          return lowerFRAMEADDR(Op, DAG);
881   case ISD::RETURNADDR:         return lowerRETURNADDR(Op, DAG);
882   case ISD::EH_RETURN:          return lowerEH_RETURN(Op, DAG);
883   case ISD::ATOMIC_FENCE:       return lowerATOMIC_FENCE(Op, DAG);
884   case ISD::SHL_PARTS:          return lowerShiftLeftParts(Op, DAG);
885   case ISD::SRA_PARTS:          return lowerShiftRightParts(Op, DAG, true);
886   case ISD::SRL_PARTS:          return lowerShiftRightParts(Op, DAG, false);
887   case ISD::LOAD:               return lowerLOAD(Op, DAG);
888   case ISD::STORE:              return lowerSTORE(Op, DAG);
889   case ISD::ADD:                return lowerADD(Op, DAG);
890   case ISD::FP_TO_SINT:         return lowerFP_TO_SINT(Op, DAG);
891   }
892   return SDValue();
893 }
894 
895 //===----------------------------------------------------------------------===//
896 //  Lower helper functions
897 //===----------------------------------------------------------------------===//
898 
899 // addLiveIn - This helper function adds the specified physical register to the
900 // MachineFunction as a live in value.  It also creates a corresponding
901 // virtual register for it.
902 static unsigned
addLiveIn(MachineFunction & MF,unsigned PReg,const TargetRegisterClass * RC)903 addLiveIn(MachineFunction &MF, unsigned PReg, const TargetRegisterClass *RC)
904 {
905   unsigned VReg = MF.getRegInfo().createVirtualRegister(RC);
906   MF.getRegInfo().addLiveIn(PReg, VReg);
907   return VReg;
908 }
909 
insertDivByZeroTrap(MachineInstr * MI,MachineBasicBlock & MBB,const TargetInstrInfo & TII,bool Is64Bit)910 static MachineBasicBlock *insertDivByZeroTrap(MachineInstr *MI,
911                                               MachineBasicBlock &MBB,
912                                               const TargetInstrInfo &TII,
913                                               bool Is64Bit) {
914   if (NoZeroDivCheck)
915     return &MBB;
916 
917   // Insert instruction "teq $divisor_reg, $zero, 7".
918   MachineBasicBlock::iterator I(MI);
919   MachineInstrBuilder MIB;
920   MachineOperand &Divisor = MI->getOperand(2);
921   MIB = BuildMI(MBB, std::next(I), MI->getDebugLoc(), TII.get(Mips::TEQ))
922     .addReg(Divisor.getReg(), getKillRegState(Divisor.isKill()))
923     .addReg(Mips::ZERO).addImm(7);
924 
925   // Use the 32-bit sub-register if this is a 64-bit division.
926   if (Is64Bit)
927     MIB->getOperand(0).setSubReg(Mips::sub_32);
928 
929   // Clear Divisor's kill flag.
930   Divisor.setIsKill(false);
931 
932   // We would normally delete the original instruction here but in this case
933   // we only needed to inject an additional instruction rather than replace it.
934 
935   return &MBB;
936 }
937 
938 MachineBasicBlock *
EmitInstrWithCustomInserter(MachineInstr * MI,MachineBasicBlock * BB) const939 MipsTargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
940                                                 MachineBasicBlock *BB) const {
941   switch (MI->getOpcode()) {
942   default:
943     llvm_unreachable("Unexpected instr type to insert");
944   case Mips::ATOMIC_LOAD_ADD_I8:
945     return emitAtomicBinaryPartword(MI, BB, 1, Mips::ADDu);
946   case Mips::ATOMIC_LOAD_ADD_I16:
947     return emitAtomicBinaryPartword(MI, BB, 2, Mips::ADDu);
948   case Mips::ATOMIC_LOAD_ADD_I32:
949     return emitAtomicBinary(MI, BB, 4, Mips::ADDu);
950   case Mips::ATOMIC_LOAD_ADD_I64:
951     return emitAtomicBinary(MI, BB, 8, Mips::DADDu);
952 
953   case Mips::ATOMIC_LOAD_AND_I8:
954     return emitAtomicBinaryPartword(MI, BB, 1, Mips::AND);
955   case Mips::ATOMIC_LOAD_AND_I16:
956     return emitAtomicBinaryPartword(MI, BB, 2, Mips::AND);
957   case Mips::ATOMIC_LOAD_AND_I32:
958     return emitAtomicBinary(MI, BB, 4, Mips::AND);
959   case Mips::ATOMIC_LOAD_AND_I64:
960     return emitAtomicBinary(MI, BB, 8, Mips::AND64);
961 
962   case Mips::ATOMIC_LOAD_OR_I8:
963     return emitAtomicBinaryPartword(MI, BB, 1, Mips::OR);
964   case Mips::ATOMIC_LOAD_OR_I16:
965     return emitAtomicBinaryPartword(MI, BB, 2, Mips::OR);
966   case Mips::ATOMIC_LOAD_OR_I32:
967     return emitAtomicBinary(MI, BB, 4, Mips::OR);
968   case Mips::ATOMIC_LOAD_OR_I64:
969     return emitAtomicBinary(MI, BB, 8, Mips::OR64);
970 
971   case Mips::ATOMIC_LOAD_XOR_I8:
972     return emitAtomicBinaryPartword(MI, BB, 1, Mips::XOR);
973   case Mips::ATOMIC_LOAD_XOR_I16:
974     return emitAtomicBinaryPartword(MI, BB, 2, Mips::XOR);
975   case Mips::ATOMIC_LOAD_XOR_I32:
976     return emitAtomicBinary(MI, BB, 4, Mips::XOR);
977   case Mips::ATOMIC_LOAD_XOR_I64:
978     return emitAtomicBinary(MI, BB, 8, Mips::XOR64);
979 
980   case Mips::ATOMIC_LOAD_NAND_I8:
981     return emitAtomicBinaryPartword(MI, BB, 1, 0, true);
982   case Mips::ATOMIC_LOAD_NAND_I16:
983     return emitAtomicBinaryPartword(MI, BB, 2, 0, true);
984   case Mips::ATOMIC_LOAD_NAND_I32:
985     return emitAtomicBinary(MI, BB, 4, 0, true);
986   case Mips::ATOMIC_LOAD_NAND_I64:
987     return emitAtomicBinary(MI, BB, 8, 0, true);
988 
989   case Mips::ATOMIC_LOAD_SUB_I8:
990     return emitAtomicBinaryPartword(MI, BB, 1, Mips::SUBu);
991   case Mips::ATOMIC_LOAD_SUB_I16:
992     return emitAtomicBinaryPartword(MI, BB, 2, Mips::SUBu);
993   case Mips::ATOMIC_LOAD_SUB_I32:
994     return emitAtomicBinary(MI, BB, 4, Mips::SUBu);
995   case Mips::ATOMIC_LOAD_SUB_I64:
996     return emitAtomicBinary(MI, BB, 8, Mips::DSUBu);
997 
998   case Mips::ATOMIC_SWAP_I8:
999     return emitAtomicBinaryPartword(MI, BB, 1, 0);
1000   case Mips::ATOMIC_SWAP_I16:
1001     return emitAtomicBinaryPartword(MI, BB, 2, 0);
1002   case Mips::ATOMIC_SWAP_I32:
1003     return emitAtomicBinary(MI, BB, 4, 0);
1004   case Mips::ATOMIC_SWAP_I64:
1005     return emitAtomicBinary(MI, BB, 8, 0);
1006 
1007   case Mips::ATOMIC_CMP_SWAP_I8:
1008     return emitAtomicCmpSwapPartword(MI, BB, 1);
1009   case Mips::ATOMIC_CMP_SWAP_I16:
1010     return emitAtomicCmpSwapPartword(MI, BB, 2);
1011   case Mips::ATOMIC_CMP_SWAP_I32:
1012     return emitAtomicCmpSwap(MI, BB, 4);
1013   case Mips::ATOMIC_CMP_SWAP_I64:
1014     return emitAtomicCmpSwap(MI, BB, 8);
1015   case Mips::PseudoSDIV:
1016   case Mips::PseudoUDIV:
1017   case Mips::DIV:
1018   case Mips::DIVU:
1019   case Mips::MOD:
1020   case Mips::MODU:
1021     return insertDivByZeroTrap(MI, *BB, *Subtarget.getInstrInfo(), false);
1022   case Mips::PseudoDSDIV:
1023   case Mips::PseudoDUDIV:
1024   case Mips::DDIV:
1025   case Mips::DDIVU:
1026   case Mips::DMOD:
1027   case Mips::DMODU:
1028     return insertDivByZeroTrap(MI, *BB, *Subtarget.getInstrInfo(), true);
1029   case Mips::SEL_D:
1030     return emitSEL_D(MI, BB);
1031 
1032   case Mips::PseudoSELECT_I:
1033   case Mips::PseudoSELECT_I64:
1034   case Mips::PseudoSELECT_S:
1035   case Mips::PseudoSELECT_D32:
1036   case Mips::PseudoSELECT_D64:
1037     return emitPseudoSELECT(MI, BB, false, Mips::BNE);
1038   case Mips::PseudoSELECTFP_F_I:
1039   case Mips::PseudoSELECTFP_F_I64:
1040   case Mips::PseudoSELECTFP_F_S:
1041   case Mips::PseudoSELECTFP_F_D32:
1042   case Mips::PseudoSELECTFP_F_D64:
1043     return emitPseudoSELECT(MI, BB, true, Mips::BC1F);
1044   case Mips::PseudoSELECTFP_T_I:
1045   case Mips::PseudoSELECTFP_T_I64:
1046   case Mips::PseudoSELECTFP_T_S:
1047   case Mips::PseudoSELECTFP_T_D32:
1048   case Mips::PseudoSELECTFP_T_D64:
1049     return emitPseudoSELECT(MI, BB, true, Mips::BC1T);
1050   }
1051 }
1052 
1053 // This function also handles Mips::ATOMIC_SWAP_I32 (when BinOpcode == 0), and
1054 // Mips::ATOMIC_LOAD_NAND_I32 (when Nand == true)
1055 MachineBasicBlock *
emitAtomicBinary(MachineInstr * MI,MachineBasicBlock * BB,unsigned Size,unsigned BinOpcode,bool Nand) const1056 MipsTargetLowering::emitAtomicBinary(MachineInstr *MI, MachineBasicBlock *BB,
1057                                      unsigned Size, unsigned BinOpcode,
1058                                      bool Nand) const {
1059   assert((Size == 4 || Size == 8) && "Unsupported size for EmitAtomicBinary.");
1060 
1061   MachineFunction *MF = BB->getParent();
1062   MachineRegisterInfo &RegInfo = MF->getRegInfo();
1063   const TargetRegisterClass *RC = getRegClassFor(MVT::getIntegerVT(Size * 8));
1064   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
1065   DebugLoc DL = MI->getDebugLoc();
1066   unsigned LL, SC, AND, NOR, ZERO, BEQ;
1067 
1068   if (Size == 4) {
1069     if (isMicroMips) {
1070       LL = Mips::LL_MM;
1071       SC = Mips::SC_MM;
1072     } else {
1073       LL = Subtarget.hasMips32r6() ? Mips::LL_R6 : Mips::LL;
1074       SC = Subtarget.hasMips32r6() ? Mips::SC_R6 : Mips::SC;
1075     }
1076     AND = Mips::AND;
1077     NOR = Mips::NOR;
1078     ZERO = Mips::ZERO;
1079     BEQ = Mips::BEQ;
1080   } else {
1081     LL = Subtarget.hasMips64r6() ? Mips::LLD_R6 : Mips::LLD;
1082     SC = Subtarget.hasMips64r6() ? Mips::SCD_R6 : Mips::SCD;
1083     AND = Mips::AND64;
1084     NOR = Mips::NOR64;
1085     ZERO = Mips::ZERO_64;
1086     BEQ = Mips::BEQ64;
1087   }
1088 
1089   unsigned OldVal = MI->getOperand(0).getReg();
1090   unsigned Ptr = MI->getOperand(1).getReg();
1091   unsigned Incr = MI->getOperand(2).getReg();
1092 
1093   unsigned StoreVal = RegInfo.createVirtualRegister(RC);
1094   unsigned AndRes = RegInfo.createVirtualRegister(RC);
1095   unsigned Success = RegInfo.createVirtualRegister(RC);
1096 
1097   // insert new blocks after the current block
1098   const BasicBlock *LLVM_BB = BB->getBasicBlock();
1099   MachineBasicBlock *loopMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1100   MachineBasicBlock *exitMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1101   MachineFunction::iterator It = ++BB->getIterator();
1102   MF->insert(It, loopMBB);
1103   MF->insert(It, exitMBB);
1104 
1105   // Transfer the remainder of BB and its successor edges to exitMBB.
1106   exitMBB->splice(exitMBB->begin(), BB,
1107                   std::next(MachineBasicBlock::iterator(MI)), BB->end());
1108   exitMBB->transferSuccessorsAndUpdatePHIs(BB);
1109 
1110   //  thisMBB:
1111   //    ...
1112   //    fallthrough --> loopMBB
1113   BB->addSuccessor(loopMBB);
1114   loopMBB->addSuccessor(loopMBB);
1115   loopMBB->addSuccessor(exitMBB);
1116 
1117   //  loopMBB:
1118   //    ll oldval, 0(ptr)
1119   //    <binop> storeval, oldval, incr
1120   //    sc success, storeval, 0(ptr)
1121   //    beq success, $0, loopMBB
1122   BB = loopMBB;
1123   BuildMI(BB, DL, TII->get(LL), OldVal).addReg(Ptr).addImm(0);
1124   if (Nand) {
1125     //  and andres, oldval, incr
1126     //  nor storeval, $0, andres
1127     BuildMI(BB, DL, TII->get(AND), AndRes).addReg(OldVal).addReg(Incr);
1128     BuildMI(BB, DL, TII->get(NOR), StoreVal).addReg(ZERO).addReg(AndRes);
1129   } else if (BinOpcode) {
1130     //  <binop> storeval, oldval, incr
1131     BuildMI(BB, DL, TII->get(BinOpcode), StoreVal).addReg(OldVal).addReg(Incr);
1132   } else {
1133     StoreVal = Incr;
1134   }
1135   BuildMI(BB, DL, TII->get(SC), Success).addReg(StoreVal).addReg(Ptr).addImm(0);
1136   BuildMI(BB, DL, TII->get(BEQ)).addReg(Success).addReg(ZERO).addMBB(loopMBB);
1137 
1138   MI->eraseFromParent(); // The instruction is gone now.
1139 
1140   return exitMBB;
1141 }
1142 
emitSignExtendToI32InReg(MachineInstr * MI,MachineBasicBlock * BB,unsigned Size,unsigned DstReg,unsigned SrcReg) const1143 MachineBasicBlock *MipsTargetLowering::emitSignExtendToI32InReg(
1144     MachineInstr *MI, MachineBasicBlock *BB, unsigned Size, unsigned DstReg,
1145     unsigned SrcReg) const {
1146   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
1147   DebugLoc DL = MI->getDebugLoc();
1148 
1149   if (Subtarget.hasMips32r2() && Size == 1) {
1150     BuildMI(BB, DL, TII->get(Mips::SEB), DstReg).addReg(SrcReg);
1151     return BB;
1152   }
1153 
1154   if (Subtarget.hasMips32r2() && Size == 2) {
1155     BuildMI(BB, DL, TII->get(Mips::SEH), DstReg).addReg(SrcReg);
1156     return BB;
1157   }
1158 
1159   MachineFunction *MF = BB->getParent();
1160   MachineRegisterInfo &RegInfo = MF->getRegInfo();
1161   const TargetRegisterClass *RC = getRegClassFor(MVT::i32);
1162   unsigned ScrReg = RegInfo.createVirtualRegister(RC);
1163 
1164   assert(Size < 32);
1165   int64_t ShiftImm = 32 - (Size * 8);
1166 
1167   BuildMI(BB, DL, TII->get(Mips::SLL), ScrReg).addReg(SrcReg).addImm(ShiftImm);
1168   BuildMI(BB, DL, TII->get(Mips::SRA), DstReg).addReg(ScrReg).addImm(ShiftImm);
1169 
1170   return BB;
1171 }
1172 
emitAtomicBinaryPartword(MachineInstr * MI,MachineBasicBlock * BB,unsigned Size,unsigned BinOpcode,bool Nand) const1173 MachineBasicBlock *MipsTargetLowering::emitAtomicBinaryPartword(
1174     MachineInstr *MI, MachineBasicBlock *BB, unsigned Size, unsigned BinOpcode,
1175     bool Nand) const {
1176   assert((Size == 1 || Size == 2) &&
1177          "Unsupported size for EmitAtomicBinaryPartial.");
1178 
1179   MachineFunction *MF = BB->getParent();
1180   MachineRegisterInfo &RegInfo = MF->getRegInfo();
1181   const TargetRegisterClass *RC = getRegClassFor(MVT::i32);
1182   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
1183   DebugLoc DL = MI->getDebugLoc();
1184 
1185   unsigned Dest = MI->getOperand(0).getReg();
1186   unsigned Ptr = MI->getOperand(1).getReg();
1187   unsigned Incr = MI->getOperand(2).getReg();
1188 
1189   unsigned AlignedAddr = RegInfo.createVirtualRegister(RC);
1190   unsigned ShiftAmt = RegInfo.createVirtualRegister(RC);
1191   unsigned Mask = RegInfo.createVirtualRegister(RC);
1192   unsigned Mask2 = RegInfo.createVirtualRegister(RC);
1193   unsigned NewVal = RegInfo.createVirtualRegister(RC);
1194   unsigned OldVal = RegInfo.createVirtualRegister(RC);
1195   unsigned Incr2 = RegInfo.createVirtualRegister(RC);
1196   unsigned MaskLSB2 = RegInfo.createVirtualRegister(RC);
1197   unsigned PtrLSB2 = RegInfo.createVirtualRegister(RC);
1198   unsigned MaskUpper = RegInfo.createVirtualRegister(RC);
1199   unsigned AndRes = RegInfo.createVirtualRegister(RC);
1200   unsigned BinOpRes = RegInfo.createVirtualRegister(RC);
1201   unsigned MaskedOldVal0 = RegInfo.createVirtualRegister(RC);
1202   unsigned StoreVal = RegInfo.createVirtualRegister(RC);
1203   unsigned MaskedOldVal1 = RegInfo.createVirtualRegister(RC);
1204   unsigned SrlRes = RegInfo.createVirtualRegister(RC);
1205   unsigned Success = RegInfo.createVirtualRegister(RC);
1206 
1207   // insert new blocks after the current block
1208   const BasicBlock *LLVM_BB = BB->getBasicBlock();
1209   MachineBasicBlock *loopMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1210   MachineBasicBlock *sinkMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1211   MachineBasicBlock *exitMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1212   MachineFunction::iterator It = ++BB->getIterator();
1213   MF->insert(It, loopMBB);
1214   MF->insert(It, sinkMBB);
1215   MF->insert(It, exitMBB);
1216 
1217   // Transfer the remainder of BB and its successor edges to exitMBB.
1218   exitMBB->splice(exitMBB->begin(), BB,
1219                   std::next(MachineBasicBlock::iterator(MI)), BB->end());
1220   exitMBB->transferSuccessorsAndUpdatePHIs(BB);
1221 
1222   BB->addSuccessor(loopMBB);
1223   loopMBB->addSuccessor(loopMBB);
1224   loopMBB->addSuccessor(sinkMBB);
1225   sinkMBB->addSuccessor(exitMBB);
1226 
1227   //  thisMBB:
1228   //    addiu   masklsb2,$0,-4                # 0xfffffffc
1229   //    and     alignedaddr,ptr,masklsb2
1230   //    andi    ptrlsb2,ptr,3
1231   //    sll     shiftamt,ptrlsb2,3
1232   //    ori     maskupper,$0,255               # 0xff
1233   //    sll     mask,maskupper,shiftamt
1234   //    nor     mask2,$0,mask
1235   //    sll     incr2,incr,shiftamt
1236 
1237   int64_t MaskImm = (Size == 1) ? 255 : 65535;
1238   BuildMI(BB, DL, TII->get(Mips::ADDiu), MaskLSB2)
1239     .addReg(Mips::ZERO).addImm(-4);
1240   BuildMI(BB, DL, TII->get(Mips::AND), AlignedAddr)
1241     .addReg(Ptr).addReg(MaskLSB2);
1242   BuildMI(BB, DL, TII->get(Mips::ANDi), PtrLSB2).addReg(Ptr).addImm(3);
1243   if (Subtarget.isLittle()) {
1244     BuildMI(BB, DL, TII->get(Mips::SLL), ShiftAmt).addReg(PtrLSB2).addImm(3);
1245   } else {
1246     unsigned Off = RegInfo.createVirtualRegister(RC);
1247     BuildMI(BB, DL, TII->get(Mips::XORi), Off)
1248       .addReg(PtrLSB2).addImm((Size == 1) ? 3 : 2);
1249     BuildMI(BB, DL, TII->get(Mips::SLL), ShiftAmt).addReg(Off).addImm(3);
1250   }
1251   BuildMI(BB, DL, TII->get(Mips::ORi), MaskUpper)
1252     .addReg(Mips::ZERO).addImm(MaskImm);
1253   BuildMI(BB, DL, TII->get(Mips::SLLV), Mask)
1254     .addReg(MaskUpper).addReg(ShiftAmt);
1255   BuildMI(BB, DL, TII->get(Mips::NOR), Mask2).addReg(Mips::ZERO).addReg(Mask);
1256   BuildMI(BB, DL, TII->get(Mips::SLLV), Incr2).addReg(Incr).addReg(ShiftAmt);
1257 
1258   // atomic.load.binop
1259   // loopMBB:
1260   //   ll      oldval,0(alignedaddr)
1261   //   binop   binopres,oldval,incr2
1262   //   and     newval,binopres,mask
1263   //   and     maskedoldval0,oldval,mask2
1264   //   or      storeval,maskedoldval0,newval
1265   //   sc      success,storeval,0(alignedaddr)
1266   //   beq     success,$0,loopMBB
1267 
1268   // atomic.swap
1269   // loopMBB:
1270   //   ll      oldval,0(alignedaddr)
1271   //   and     newval,incr2,mask
1272   //   and     maskedoldval0,oldval,mask2
1273   //   or      storeval,maskedoldval0,newval
1274   //   sc      success,storeval,0(alignedaddr)
1275   //   beq     success,$0,loopMBB
1276 
1277   BB = loopMBB;
1278   unsigned LL = isMicroMips ? Mips::LL_MM : Mips::LL;
1279   BuildMI(BB, DL, TII->get(LL), OldVal).addReg(AlignedAddr).addImm(0);
1280   if (Nand) {
1281     //  and andres, oldval, incr2
1282     //  nor binopres, $0, andres
1283     //  and newval, binopres, mask
1284     BuildMI(BB, DL, TII->get(Mips::AND), AndRes).addReg(OldVal).addReg(Incr2);
1285     BuildMI(BB, DL, TII->get(Mips::NOR), BinOpRes)
1286       .addReg(Mips::ZERO).addReg(AndRes);
1287     BuildMI(BB, DL, TII->get(Mips::AND), NewVal).addReg(BinOpRes).addReg(Mask);
1288   } else if (BinOpcode) {
1289     //  <binop> binopres, oldval, incr2
1290     //  and newval, binopres, mask
1291     BuildMI(BB, DL, TII->get(BinOpcode), BinOpRes).addReg(OldVal).addReg(Incr2);
1292     BuildMI(BB, DL, TII->get(Mips::AND), NewVal).addReg(BinOpRes).addReg(Mask);
1293   } else { // atomic.swap
1294     //  and newval, incr2, mask
1295     BuildMI(BB, DL, TII->get(Mips::AND), NewVal).addReg(Incr2).addReg(Mask);
1296   }
1297 
1298   BuildMI(BB, DL, TII->get(Mips::AND), MaskedOldVal0)
1299     .addReg(OldVal).addReg(Mask2);
1300   BuildMI(BB, DL, TII->get(Mips::OR), StoreVal)
1301     .addReg(MaskedOldVal0).addReg(NewVal);
1302   unsigned SC = isMicroMips ? Mips::SC_MM : Mips::SC;
1303   BuildMI(BB, DL, TII->get(SC), Success)
1304     .addReg(StoreVal).addReg(AlignedAddr).addImm(0);
1305   BuildMI(BB, DL, TII->get(Mips::BEQ))
1306     .addReg(Success).addReg(Mips::ZERO).addMBB(loopMBB);
1307 
1308   //  sinkMBB:
1309   //    and     maskedoldval1,oldval,mask
1310   //    srl     srlres,maskedoldval1,shiftamt
1311   //    sign_extend dest,srlres
1312   BB = sinkMBB;
1313 
1314   BuildMI(BB, DL, TII->get(Mips::AND), MaskedOldVal1)
1315     .addReg(OldVal).addReg(Mask);
1316   BuildMI(BB, DL, TII->get(Mips::SRLV), SrlRes)
1317       .addReg(MaskedOldVal1).addReg(ShiftAmt);
1318   BB = emitSignExtendToI32InReg(MI, BB, Size, Dest, SrlRes);
1319 
1320   MI->eraseFromParent(); // The instruction is gone now.
1321 
1322   return exitMBB;
1323 }
1324 
emitAtomicCmpSwap(MachineInstr * MI,MachineBasicBlock * BB,unsigned Size) const1325 MachineBasicBlock * MipsTargetLowering::emitAtomicCmpSwap(MachineInstr *MI,
1326                                                           MachineBasicBlock *BB,
1327                                                           unsigned Size) const {
1328   assert((Size == 4 || Size == 8) && "Unsupported size for EmitAtomicCmpSwap.");
1329 
1330   MachineFunction *MF = BB->getParent();
1331   MachineRegisterInfo &RegInfo = MF->getRegInfo();
1332   const TargetRegisterClass *RC = getRegClassFor(MVT::getIntegerVT(Size * 8));
1333   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
1334   DebugLoc DL = MI->getDebugLoc();
1335   unsigned LL, SC, ZERO, BNE, BEQ;
1336 
1337    if (Size == 4) {
1338      if (isMicroMips) {
1339        LL = Mips::LL_MM;
1340        SC = Mips::SC_MM;
1341      } else {
1342        LL = Subtarget.hasMips32r6() ? Mips::LL_R6 : Mips::LL;
1343        SC = Subtarget.hasMips32r6() ? Mips::SC_R6 : Mips::SC;
1344      }
1345     ZERO = Mips::ZERO;
1346     BNE = Mips::BNE;
1347     BEQ = Mips::BEQ;
1348   } else {
1349     LL = Subtarget.hasMips64r6() ? Mips::LLD_R6 : Mips::LLD;
1350     SC = Subtarget.hasMips64r6() ? Mips::SCD_R6 : Mips::SCD;
1351     ZERO = Mips::ZERO_64;
1352     BNE = Mips::BNE64;
1353     BEQ = Mips::BEQ64;
1354   }
1355 
1356   unsigned Dest    = MI->getOperand(0).getReg();
1357   unsigned Ptr     = MI->getOperand(1).getReg();
1358   unsigned OldVal  = MI->getOperand(2).getReg();
1359   unsigned NewVal  = MI->getOperand(3).getReg();
1360 
1361   unsigned Success = RegInfo.createVirtualRegister(RC);
1362 
1363   // insert new blocks after the current block
1364   const BasicBlock *LLVM_BB = BB->getBasicBlock();
1365   MachineBasicBlock *loop1MBB = MF->CreateMachineBasicBlock(LLVM_BB);
1366   MachineBasicBlock *loop2MBB = MF->CreateMachineBasicBlock(LLVM_BB);
1367   MachineBasicBlock *exitMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1368   MachineFunction::iterator It = ++BB->getIterator();
1369   MF->insert(It, loop1MBB);
1370   MF->insert(It, loop2MBB);
1371   MF->insert(It, exitMBB);
1372 
1373   // Transfer the remainder of BB and its successor edges to exitMBB.
1374   exitMBB->splice(exitMBB->begin(), BB,
1375                   std::next(MachineBasicBlock::iterator(MI)), BB->end());
1376   exitMBB->transferSuccessorsAndUpdatePHIs(BB);
1377 
1378   //  thisMBB:
1379   //    ...
1380   //    fallthrough --> loop1MBB
1381   BB->addSuccessor(loop1MBB);
1382   loop1MBB->addSuccessor(exitMBB);
1383   loop1MBB->addSuccessor(loop2MBB);
1384   loop2MBB->addSuccessor(loop1MBB);
1385   loop2MBB->addSuccessor(exitMBB);
1386 
1387   // loop1MBB:
1388   //   ll dest, 0(ptr)
1389   //   bne dest, oldval, exitMBB
1390   BB = loop1MBB;
1391   BuildMI(BB, DL, TII->get(LL), Dest).addReg(Ptr).addImm(0);
1392   BuildMI(BB, DL, TII->get(BNE))
1393     .addReg(Dest).addReg(OldVal).addMBB(exitMBB);
1394 
1395   // loop2MBB:
1396   //   sc success, newval, 0(ptr)
1397   //   beq success, $0, loop1MBB
1398   BB = loop2MBB;
1399   BuildMI(BB, DL, TII->get(SC), Success)
1400     .addReg(NewVal).addReg(Ptr).addImm(0);
1401   BuildMI(BB, DL, TII->get(BEQ))
1402     .addReg(Success).addReg(ZERO).addMBB(loop1MBB);
1403 
1404   MI->eraseFromParent(); // The instruction is gone now.
1405 
1406   return exitMBB;
1407 }
1408 
1409 MachineBasicBlock *
emitAtomicCmpSwapPartword(MachineInstr * MI,MachineBasicBlock * BB,unsigned Size) const1410 MipsTargetLowering::emitAtomicCmpSwapPartword(MachineInstr *MI,
1411                                               MachineBasicBlock *BB,
1412                                               unsigned Size) const {
1413   assert((Size == 1 || Size == 2) &&
1414       "Unsupported size for EmitAtomicCmpSwapPartial.");
1415 
1416   MachineFunction *MF = BB->getParent();
1417   MachineRegisterInfo &RegInfo = MF->getRegInfo();
1418   const TargetRegisterClass *RC = getRegClassFor(MVT::i32);
1419   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
1420   DebugLoc DL = MI->getDebugLoc();
1421 
1422   unsigned Dest    = MI->getOperand(0).getReg();
1423   unsigned Ptr     = MI->getOperand(1).getReg();
1424   unsigned CmpVal  = MI->getOperand(2).getReg();
1425   unsigned NewVal  = MI->getOperand(3).getReg();
1426 
1427   unsigned AlignedAddr = RegInfo.createVirtualRegister(RC);
1428   unsigned ShiftAmt = RegInfo.createVirtualRegister(RC);
1429   unsigned Mask = RegInfo.createVirtualRegister(RC);
1430   unsigned Mask2 = RegInfo.createVirtualRegister(RC);
1431   unsigned ShiftedCmpVal = RegInfo.createVirtualRegister(RC);
1432   unsigned OldVal = RegInfo.createVirtualRegister(RC);
1433   unsigned MaskedOldVal0 = RegInfo.createVirtualRegister(RC);
1434   unsigned ShiftedNewVal = RegInfo.createVirtualRegister(RC);
1435   unsigned MaskLSB2 = RegInfo.createVirtualRegister(RC);
1436   unsigned PtrLSB2 = RegInfo.createVirtualRegister(RC);
1437   unsigned MaskUpper = RegInfo.createVirtualRegister(RC);
1438   unsigned MaskedCmpVal = RegInfo.createVirtualRegister(RC);
1439   unsigned MaskedNewVal = RegInfo.createVirtualRegister(RC);
1440   unsigned MaskedOldVal1 = RegInfo.createVirtualRegister(RC);
1441   unsigned StoreVal = RegInfo.createVirtualRegister(RC);
1442   unsigned SrlRes = RegInfo.createVirtualRegister(RC);
1443   unsigned Success = RegInfo.createVirtualRegister(RC);
1444 
1445   // insert new blocks after the current block
1446   const BasicBlock *LLVM_BB = BB->getBasicBlock();
1447   MachineBasicBlock *loop1MBB = MF->CreateMachineBasicBlock(LLVM_BB);
1448   MachineBasicBlock *loop2MBB = MF->CreateMachineBasicBlock(LLVM_BB);
1449   MachineBasicBlock *sinkMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1450   MachineBasicBlock *exitMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1451   MachineFunction::iterator It = ++BB->getIterator();
1452   MF->insert(It, loop1MBB);
1453   MF->insert(It, loop2MBB);
1454   MF->insert(It, sinkMBB);
1455   MF->insert(It, exitMBB);
1456 
1457   // Transfer the remainder of BB and its successor edges to exitMBB.
1458   exitMBB->splice(exitMBB->begin(), BB,
1459                   std::next(MachineBasicBlock::iterator(MI)), BB->end());
1460   exitMBB->transferSuccessorsAndUpdatePHIs(BB);
1461 
1462   BB->addSuccessor(loop1MBB);
1463   loop1MBB->addSuccessor(sinkMBB);
1464   loop1MBB->addSuccessor(loop2MBB);
1465   loop2MBB->addSuccessor(loop1MBB);
1466   loop2MBB->addSuccessor(sinkMBB);
1467   sinkMBB->addSuccessor(exitMBB);
1468 
1469   // FIXME: computation of newval2 can be moved to loop2MBB.
1470   //  thisMBB:
1471   //    addiu   masklsb2,$0,-4                # 0xfffffffc
1472   //    and     alignedaddr,ptr,masklsb2
1473   //    andi    ptrlsb2,ptr,3
1474   //    sll     shiftamt,ptrlsb2,3
1475   //    ori     maskupper,$0,255               # 0xff
1476   //    sll     mask,maskupper,shiftamt
1477   //    nor     mask2,$0,mask
1478   //    andi    maskedcmpval,cmpval,255
1479   //    sll     shiftedcmpval,maskedcmpval,shiftamt
1480   //    andi    maskednewval,newval,255
1481   //    sll     shiftednewval,maskednewval,shiftamt
1482   int64_t MaskImm = (Size == 1) ? 255 : 65535;
1483   BuildMI(BB, DL, TII->get(Mips::ADDiu), MaskLSB2)
1484     .addReg(Mips::ZERO).addImm(-4);
1485   BuildMI(BB, DL, TII->get(Mips::AND), AlignedAddr)
1486     .addReg(Ptr).addReg(MaskLSB2);
1487   BuildMI(BB, DL, TII->get(Mips::ANDi), PtrLSB2).addReg(Ptr).addImm(3);
1488   if (Subtarget.isLittle()) {
1489     BuildMI(BB, DL, TII->get(Mips::SLL), ShiftAmt).addReg(PtrLSB2).addImm(3);
1490   } else {
1491     unsigned Off = RegInfo.createVirtualRegister(RC);
1492     BuildMI(BB, DL, TII->get(Mips::XORi), Off)
1493       .addReg(PtrLSB2).addImm((Size == 1) ? 3 : 2);
1494     BuildMI(BB, DL, TII->get(Mips::SLL), ShiftAmt).addReg(Off).addImm(3);
1495   }
1496   BuildMI(BB, DL, TII->get(Mips::ORi), MaskUpper)
1497     .addReg(Mips::ZERO).addImm(MaskImm);
1498   BuildMI(BB, DL, TII->get(Mips::SLLV), Mask)
1499     .addReg(MaskUpper).addReg(ShiftAmt);
1500   BuildMI(BB, DL, TII->get(Mips::NOR), Mask2).addReg(Mips::ZERO).addReg(Mask);
1501   BuildMI(BB, DL, TII->get(Mips::ANDi), MaskedCmpVal)
1502     .addReg(CmpVal).addImm(MaskImm);
1503   BuildMI(BB, DL, TII->get(Mips::SLLV), ShiftedCmpVal)
1504     .addReg(MaskedCmpVal).addReg(ShiftAmt);
1505   BuildMI(BB, DL, TII->get(Mips::ANDi), MaskedNewVal)
1506     .addReg(NewVal).addImm(MaskImm);
1507   BuildMI(BB, DL, TII->get(Mips::SLLV), ShiftedNewVal)
1508     .addReg(MaskedNewVal).addReg(ShiftAmt);
1509 
1510   //  loop1MBB:
1511   //    ll      oldval,0(alginedaddr)
1512   //    and     maskedoldval0,oldval,mask
1513   //    bne     maskedoldval0,shiftedcmpval,sinkMBB
1514   BB = loop1MBB;
1515   unsigned LL = isMicroMips ? Mips::LL_MM : Mips::LL;
1516   BuildMI(BB, DL, TII->get(LL), OldVal).addReg(AlignedAddr).addImm(0);
1517   BuildMI(BB, DL, TII->get(Mips::AND), MaskedOldVal0)
1518     .addReg(OldVal).addReg(Mask);
1519   BuildMI(BB, DL, TII->get(Mips::BNE))
1520     .addReg(MaskedOldVal0).addReg(ShiftedCmpVal).addMBB(sinkMBB);
1521 
1522   //  loop2MBB:
1523   //    and     maskedoldval1,oldval,mask2
1524   //    or      storeval,maskedoldval1,shiftednewval
1525   //    sc      success,storeval,0(alignedaddr)
1526   //    beq     success,$0,loop1MBB
1527   BB = loop2MBB;
1528   BuildMI(BB, DL, TII->get(Mips::AND), MaskedOldVal1)
1529     .addReg(OldVal).addReg(Mask2);
1530   BuildMI(BB, DL, TII->get(Mips::OR), StoreVal)
1531     .addReg(MaskedOldVal1).addReg(ShiftedNewVal);
1532   unsigned SC = isMicroMips ? Mips::SC_MM : Mips::SC;
1533   BuildMI(BB, DL, TII->get(SC), Success)
1534       .addReg(StoreVal).addReg(AlignedAddr).addImm(0);
1535   BuildMI(BB, DL, TII->get(Mips::BEQ))
1536       .addReg(Success).addReg(Mips::ZERO).addMBB(loop1MBB);
1537 
1538   //  sinkMBB:
1539   //    srl     srlres,maskedoldval0,shiftamt
1540   //    sign_extend dest,srlres
1541   BB = sinkMBB;
1542 
1543   BuildMI(BB, DL, TII->get(Mips::SRLV), SrlRes)
1544       .addReg(MaskedOldVal0).addReg(ShiftAmt);
1545   BB = emitSignExtendToI32InReg(MI, BB, Size, Dest, SrlRes);
1546 
1547   MI->eraseFromParent();   // The instruction is gone now.
1548 
1549   return exitMBB;
1550 }
1551 
emitSEL_D(MachineInstr * MI,MachineBasicBlock * BB) const1552 MachineBasicBlock *MipsTargetLowering::emitSEL_D(MachineInstr *MI,
1553                                                  MachineBasicBlock *BB) const {
1554   MachineFunction *MF = BB->getParent();
1555   const TargetRegisterInfo *TRI = Subtarget.getRegisterInfo();
1556   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
1557   MachineRegisterInfo &RegInfo = MF->getRegInfo();
1558   DebugLoc DL = MI->getDebugLoc();
1559   MachineBasicBlock::iterator II(MI);
1560 
1561   unsigned Fc = MI->getOperand(1).getReg();
1562   const auto &FGR64RegClass = TRI->getRegClass(Mips::FGR64RegClassID);
1563 
1564   unsigned Fc2 = RegInfo.createVirtualRegister(FGR64RegClass);
1565 
1566   BuildMI(*BB, II, DL, TII->get(Mips::SUBREG_TO_REG), Fc2)
1567       .addImm(0)
1568       .addReg(Fc)
1569       .addImm(Mips::sub_lo);
1570 
1571   // We don't erase the original instruction, we just replace the condition
1572   // register with the 64-bit super-register.
1573   MI->getOperand(1).setReg(Fc2);
1574 
1575   return BB;
1576 }
1577 
1578 //===----------------------------------------------------------------------===//
1579 //  Misc Lower Operation implementation
1580 //===----------------------------------------------------------------------===//
lowerBR_JT(SDValue Op,SelectionDAG & DAG) const1581 SDValue MipsTargetLowering::lowerBR_JT(SDValue Op, SelectionDAG &DAG) const {
1582   SDValue Chain = Op.getOperand(0);
1583   SDValue Table = Op.getOperand(1);
1584   SDValue Index = Op.getOperand(2);
1585   SDLoc DL(Op);
1586   auto &TD = DAG.getDataLayout();
1587   EVT PTy = getPointerTy(TD);
1588   unsigned EntrySize =
1589       DAG.getMachineFunction().getJumpTableInfo()->getEntrySize(TD);
1590 
1591   Index = DAG.getNode(ISD::MUL, DL, PTy, Index,
1592                       DAG.getConstant(EntrySize, DL, PTy));
1593   SDValue Addr = DAG.getNode(ISD::ADD, DL, PTy, Index, Table);
1594 
1595   EVT MemVT = EVT::getIntegerVT(*DAG.getContext(), EntrySize * 8);
1596   Addr =
1597       DAG.getExtLoad(ISD::SEXTLOAD, DL, PTy, Chain, Addr,
1598                      MachinePointerInfo::getJumpTable(DAG.getMachineFunction()),
1599                      MemVT, false, false, false, 0);
1600   Chain = Addr.getValue(1);
1601 
1602   if ((getTargetMachine().getRelocationModel() == Reloc::PIC_) || ABI.IsN64()) {
1603     // For PIC, the sequence is:
1604     // BRIND(load(Jumptable + index) + RelocBase)
1605     // RelocBase can be JumpTable, GOT or some sort of global base.
1606     Addr = DAG.getNode(ISD::ADD, DL, PTy, Addr,
1607                        getPICJumpTableRelocBase(Table, DAG));
1608   }
1609 
1610   return DAG.getNode(ISD::BRIND, DL, MVT::Other, Chain, Addr);
1611 }
1612 
lowerBRCOND(SDValue Op,SelectionDAG & DAG) const1613 SDValue MipsTargetLowering::lowerBRCOND(SDValue Op, SelectionDAG &DAG) const {
1614   // The first operand is the chain, the second is the condition, the third is
1615   // the block to branch to if the condition is true.
1616   SDValue Chain = Op.getOperand(0);
1617   SDValue Dest = Op.getOperand(2);
1618   SDLoc DL(Op);
1619 
1620   assert(!Subtarget.hasMips32r6() && !Subtarget.hasMips64r6());
1621   SDValue CondRes = createFPCmp(DAG, Op.getOperand(1));
1622 
1623   // Return if flag is not set by a floating point comparison.
1624   if (CondRes.getOpcode() != MipsISD::FPCmp)
1625     return Op;
1626 
1627   SDValue CCNode  = CondRes.getOperand(2);
1628   Mips::CondCode CC =
1629     (Mips::CondCode)cast<ConstantSDNode>(CCNode)->getZExtValue();
1630   unsigned Opc = invertFPCondCodeUser(CC) ? Mips::BRANCH_F : Mips::BRANCH_T;
1631   SDValue BrCode = DAG.getConstant(Opc, DL, MVT::i32);
1632   SDValue FCC0 = DAG.getRegister(Mips::FCC0, MVT::i32);
1633   return DAG.getNode(MipsISD::FPBrcond, DL, Op.getValueType(), Chain, BrCode,
1634                      FCC0, Dest, CondRes);
1635 }
1636 
1637 SDValue MipsTargetLowering::
lowerSELECT(SDValue Op,SelectionDAG & DAG) const1638 lowerSELECT(SDValue Op, SelectionDAG &DAG) const
1639 {
1640   assert(!Subtarget.hasMips32r6() && !Subtarget.hasMips64r6());
1641   SDValue Cond = createFPCmp(DAG, Op.getOperand(0));
1642 
1643   // Return if flag is not set by a floating point comparison.
1644   if (Cond.getOpcode() != MipsISD::FPCmp)
1645     return Op;
1646 
1647   return createCMovFP(DAG, Cond, Op.getOperand(1), Op.getOperand(2),
1648                       SDLoc(Op));
1649 }
1650 
1651 SDValue MipsTargetLowering::
lowerSELECT_CC(SDValue Op,SelectionDAG & DAG) const1652 lowerSELECT_CC(SDValue Op, SelectionDAG &DAG) const
1653 {
1654   SDLoc DL(Op);
1655   EVT Ty = Op.getOperand(0).getValueType();
1656   SDValue Cond =
1657       DAG.getNode(ISD::SETCC, DL, getSetCCResultType(DAG.getDataLayout(),
1658                                                      *DAG.getContext(), Ty),
1659                   Op.getOperand(0), Op.getOperand(1), Op.getOperand(4));
1660 
1661   return DAG.getNode(ISD::SELECT, DL, Op.getValueType(), Cond, Op.getOperand(2),
1662                      Op.getOperand(3));
1663 }
1664 
lowerSETCC(SDValue Op,SelectionDAG & DAG) const1665 SDValue MipsTargetLowering::lowerSETCC(SDValue Op, SelectionDAG &DAG) const {
1666   assert(!Subtarget.hasMips32r6() && !Subtarget.hasMips64r6());
1667   SDValue Cond = createFPCmp(DAG, Op);
1668 
1669   assert(Cond.getOpcode() == MipsISD::FPCmp &&
1670          "Floating point operand expected.");
1671 
1672   SDLoc DL(Op);
1673   SDValue True  = DAG.getConstant(1, DL, MVT::i32);
1674   SDValue False = DAG.getConstant(0, DL, MVT::i32);
1675 
1676   return createCMovFP(DAG, Cond, True, False, DL);
1677 }
1678 
lowerGlobalAddress(SDValue Op,SelectionDAG & DAG) const1679 SDValue MipsTargetLowering::lowerGlobalAddress(SDValue Op,
1680                                                SelectionDAG &DAG) const {
1681   EVT Ty = Op.getValueType();
1682   GlobalAddressSDNode *N = cast<GlobalAddressSDNode>(Op);
1683   const GlobalValue *GV = N->getGlobal();
1684 
1685   if (getTargetMachine().getRelocationModel() != Reloc::PIC_ && !ABI.IsN64()) {
1686     const MipsTargetObjectFile *TLOF =
1687         static_cast<const MipsTargetObjectFile *>(
1688             getTargetMachine().getObjFileLowering());
1689     if (TLOF->IsGlobalInSmallSection(GV, getTargetMachine()))
1690       // %gp_rel relocation
1691       return getAddrGPRel(N, SDLoc(N), Ty, DAG);
1692 
1693     // %hi/%lo relocation
1694     return getAddrNonPIC(N, SDLoc(N), Ty, DAG);
1695   }
1696 
1697   if (GV->hasInternalLinkage() || (GV->hasLocalLinkage() && !isa<Function>(GV)))
1698     return getAddrLocal(N, SDLoc(N), Ty, DAG, ABI.IsN32() || ABI.IsN64());
1699 
1700   if (LargeGOT)
1701     return getAddrGlobalLargeGOT(
1702         N, SDLoc(N), Ty, DAG, MipsII::MO_GOT_HI16, MipsII::MO_GOT_LO16,
1703         DAG.getEntryNode(),
1704         MachinePointerInfo::getGOT(DAG.getMachineFunction()));
1705 
1706   return getAddrGlobal(
1707       N, SDLoc(N), Ty, DAG,
1708       (ABI.IsN32() || ABI.IsN64()) ? MipsII::MO_GOT_DISP : MipsII::MO_GOT16,
1709       DAG.getEntryNode(), MachinePointerInfo::getGOT(DAG.getMachineFunction()));
1710 }
1711 
lowerBlockAddress(SDValue Op,SelectionDAG & DAG) const1712 SDValue MipsTargetLowering::lowerBlockAddress(SDValue Op,
1713                                               SelectionDAG &DAG) const {
1714   BlockAddressSDNode *N = cast<BlockAddressSDNode>(Op);
1715   EVT Ty = Op.getValueType();
1716 
1717   if (getTargetMachine().getRelocationModel() != Reloc::PIC_ && !ABI.IsN64())
1718     return getAddrNonPIC(N, SDLoc(N), Ty, DAG);
1719 
1720   return getAddrLocal(N, SDLoc(N), Ty, DAG, ABI.IsN32() || ABI.IsN64());
1721 }
1722 
1723 SDValue MipsTargetLowering::
lowerGlobalTLSAddress(SDValue Op,SelectionDAG & DAG) const1724 lowerGlobalTLSAddress(SDValue Op, SelectionDAG &DAG) const
1725 {
1726   // If the relocation model is PIC, use the General Dynamic TLS Model or
1727   // Local Dynamic TLS model, otherwise use the Initial Exec or
1728   // Local Exec TLS Model.
1729 
1730   GlobalAddressSDNode *GA = cast<GlobalAddressSDNode>(Op);
1731   if (DAG.getTarget().Options.EmulatedTLS)
1732     return LowerToTLSEmulatedModel(GA, DAG);
1733 
1734   SDLoc DL(GA);
1735   const GlobalValue *GV = GA->getGlobal();
1736   EVT PtrVT = getPointerTy(DAG.getDataLayout());
1737 
1738   TLSModel::Model model = getTargetMachine().getTLSModel(GV);
1739 
1740   if (model == TLSModel::GeneralDynamic || model == TLSModel::LocalDynamic) {
1741     // General Dynamic and Local Dynamic TLS Model.
1742     unsigned Flag = (model == TLSModel::LocalDynamic) ? MipsII::MO_TLSLDM
1743                                                       : MipsII::MO_TLSGD;
1744 
1745     SDValue TGA = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0, Flag);
1746     SDValue Argument = DAG.getNode(MipsISD::Wrapper, DL, PtrVT,
1747                                    getGlobalReg(DAG, PtrVT), TGA);
1748     unsigned PtrSize = PtrVT.getSizeInBits();
1749     IntegerType *PtrTy = Type::getIntNTy(*DAG.getContext(), PtrSize);
1750 
1751     SDValue TlsGetAddr = DAG.getExternalSymbol("__tls_get_addr", PtrVT);
1752 
1753     ArgListTy Args;
1754     ArgListEntry Entry;
1755     Entry.Node = Argument;
1756     Entry.Ty = PtrTy;
1757     Args.push_back(Entry);
1758 
1759     TargetLowering::CallLoweringInfo CLI(DAG);
1760     CLI.setDebugLoc(DL).setChain(DAG.getEntryNode())
1761       .setCallee(CallingConv::C, PtrTy, TlsGetAddr, std::move(Args), 0);
1762     std::pair<SDValue, SDValue> CallResult = LowerCallTo(CLI);
1763 
1764     SDValue Ret = CallResult.first;
1765 
1766     if (model != TLSModel::LocalDynamic)
1767       return Ret;
1768 
1769     SDValue TGAHi = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0,
1770                                                MipsII::MO_DTPREL_HI);
1771     SDValue Hi = DAG.getNode(MipsISD::Hi, DL, PtrVT, TGAHi);
1772     SDValue TGALo = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0,
1773                                                MipsII::MO_DTPREL_LO);
1774     SDValue Lo = DAG.getNode(MipsISD::Lo, DL, PtrVT, TGALo);
1775     SDValue Add = DAG.getNode(ISD::ADD, DL, PtrVT, Hi, Ret);
1776     return DAG.getNode(ISD::ADD, DL, PtrVT, Add, Lo);
1777   }
1778 
1779   SDValue Offset;
1780   if (model == TLSModel::InitialExec) {
1781     // Initial Exec TLS Model
1782     SDValue TGA = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0,
1783                                              MipsII::MO_GOTTPREL);
1784     TGA = DAG.getNode(MipsISD::Wrapper, DL, PtrVT, getGlobalReg(DAG, PtrVT),
1785                       TGA);
1786     Offset = DAG.getLoad(PtrVT, DL,
1787                          DAG.getEntryNode(), TGA, MachinePointerInfo(),
1788                          false, false, false, 0);
1789   } else {
1790     // Local Exec TLS Model
1791     assert(model == TLSModel::LocalExec);
1792     SDValue TGAHi = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0,
1793                                                MipsII::MO_TPREL_HI);
1794     SDValue TGALo = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0,
1795                                                MipsII::MO_TPREL_LO);
1796     SDValue Hi = DAG.getNode(MipsISD::Hi, DL, PtrVT, TGAHi);
1797     SDValue Lo = DAG.getNode(MipsISD::Lo, DL, PtrVT, TGALo);
1798     Offset = DAG.getNode(ISD::ADD, DL, PtrVT, Hi, Lo);
1799   }
1800 
1801   SDValue ThreadPointer = DAG.getNode(MipsISD::ThreadPointer, DL, PtrVT);
1802   return DAG.getNode(ISD::ADD, DL, PtrVT, ThreadPointer, Offset);
1803 }
1804 
1805 SDValue MipsTargetLowering::
lowerJumpTable(SDValue Op,SelectionDAG & DAG) const1806 lowerJumpTable(SDValue Op, SelectionDAG &DAG) const
1807 {
1808   JumpTableSDNode *N = cast<JumpTableSDNode>(Op);
1809   EVT Ty = Op.getValueType();
1810 
1811   if (getTargetMachine().getRelocationModel() != Reloc::PIC_ && !ABI.IsN64())
1812     return getAddrNonPIC(N, SDLoc(N), Ty, DAG);
1813 
1814   return getAddrLocal(N, SDLoc(N), Ty, DAG, ABI.IsN32() || ABI.IsN64());
1815 }
1816 
1817 SDValue MipsTargetLowering::
lowerConstantPool(SDValue Op,SelectionDAG & DAG) const1818 lowerConstantPool(SDValue Op, SelectionDAG &DAG) const
1819 {
1820   ConstantPoolSDNode *N = cast<ConstantPoolSDNode>(Op);
1821   EVT Ty = Op.getValueType();
1822 
1823   if (getTargetMachine().getRelocationModel() != Reloc::PIC_ && !ABI.IsN64()) {
1824     const MipsTargetObjectFile *TLOF =
1825         static_cast<const MipsTargetObjectFile *>(
1826             getTargetMachine().getObjFileLowering());
1827 
1828     if (TLOF->IsConstantInSmallSection(DAG.getDataLayout(), N->getConstVal(),
1829                                        getTargetMachine()))
1830       // %gp_rel relocation
1831       return getAddrGPRel(N, SDLoc(N), Ty, DAG);
1832 
1833     return getAddrNonPIC(N, SDLoc(N), Ty, DAG);
1834   }
1835 
1836   return getAddrLocal(N, SDLoc(N), Ty, DAG, ABI.IsN32() || ABI.IsN64());
1837 }
1838 
lowerVASTART(SDValue Op,SelectionDAG & DAG) const1839 SDValue MipsTargetLowering::lowerVASTART(SDValue Op, SelectionDAG &DAG) const {
1840   MachineFunction &MF = DAG.getMachineFunction();
1841   MipsFunctionInfo *FuncInfo = MF.getInfo<MipsFunctionInfo>();
1842 
1843   SDLoc DL(Op);
1844   SDValue FI = DAG.getFrameIndex(FuncInfo->getVarArgsFrameIndex(),
1845                                  getPointerTy(MF.getDataLayout()));
1846 
1847   // vastart just stores the address of the VarArgsFrameIndex slot into the
1848   // memory location argument.
1849   const Value *SV = cast<SrcValueSDNode>(Op.getOperand(2))->getValue();
1850   return DAG.getStore(Op.getOperand(0), DL, FI, Op.getOperand(1),
1851                       MachinePointerInfo(SV), false, false, 0);
1852 }
1853 
lowerVAARG(SDValue Op,SelectionDAG & DAG) const1854 SDValue MipsTargetLowering::lowerVAARG(SDValue Op, SelectionDAG &DAG) const {
1855   SDNode *Node = Op.getNode();
1856   EVT VT = Node->getValueType(0);
1857   SDValue Chain = Node->getOperand(0);
1858   SDValue VAListPtr = Node->getOperand(1);
1859   unsigned Align = Node->getConstantOperandVal(3);
1860   const Value *SV = cast<SrcValueSDNode>(Node->getOperand(2))->getValue();
1861   SDLoc DL(Node);
1862   unsigned ArgSlotSizeInBytes = (ABI.IsN32() || ABI.IsN64()) ? 8 : 4;
1863 
1864   SDValue VAListLoad =
1865       DAG.getLoad(getPointerTy(DAG.getDataLayout()), DL, Chain, VAListPtr,
1866                   MachinePointerInfo(SV), false, false, false, 0);
1867   SDValue VAList = VAListLoad;
1868 
1869   // Re-align the pointer if necessary.
1870   // It should only ever be necessary for 64-bit types on O32 since the minimum
1871   // argument alignment is the same as the maximum type alignment for N32/N64.
1872   //
1873   // FIXME: We currently align too often. The code generator doesn't notice
1874   //        when the pointer is still aligned from the last va_arg (or pair of
1875   //        va_args for the i64 on O32 case).
1876   if (Align > getMinStackArgumentAlignment()) {
1877     assert(((Align & (Align-1)) == 0) && "Expected Align to be a power of 2");
1878 
1879     VAList = DAG.getNode(ISD::ADD, DL, VAList.getValueType(), VAList,
1880                          DAG.getConstant(Align - 1, DL, VAList.getValueType()));
1881 
1882     VAList = DAG.getNode(ISD::AND, DL, VAList.getValueType(), VAList,
1883                          DAG.getConstant(-(int64_t)Align, DL,
1884                                          VAList.getValueType()));
1885   }
1886 
1887   // Increment the pointer, VAList, to the next vaarg.
1888   auto &TD = DAG.getDataLayout();
1889   unsigned ArgSizeInBytes =
1890       TD.getTypeAllocSize(VT.getTypeForEVT(*DAG.getContext()));
1891   SDValue Tmp3 = DAG.getNode(ISD::ADD, DL, VAList.getValueType(), VAList,
1892                              DAG.getConstant(RoundUpToAlignment(ArgSizeInBytes,
1893                                                             ArgSlotSizeInBytes),
1894                                              DL, VAList.getValueType()));
1895   // Store the incremented VAList to the legalized pointer
1896   Chain = DAG.getStore(VAListLoad.getValue(1), DL, Tmp3, VAListPtr,
1897                       MachinePointerInfo(SV), false, false, 0);
1898 
1899   // In big-endian mode we must adjust the pointer when the load size is smaller
1900   // than the argument slot size. We must also reduce the known alignment to
1901   // match. For example in the N64 ABI, we must add 4 bytes to the offset to get
1902   // the correct half of the slot, and reduce the alignment from 8 (slot
1903   // alignment) down to 4 (type alignment).
1904   if (!Subtarget.isLittle() && ArgSizeInBytes < ArgSlotSizeInBytes) {
1905     unsigned Adjustment = ArgSlotSizeInBytes - ArgSizeInBytes;
1906     VAList = DAG.getNode(ISD::ADD, DL, VAListPtr.getValueType(), VAList,
1907                          DAG.getIntPtrConstant(Adjustment, DL));
1908   }
1909   // Load the actual argument out of the pointer VAList
1910   return DAG.getLoad(VT, DL, Chain, VAList, MachinePointerInfo(), false, false,
1911                      false, 0);
1912 }
1913 
lowerFCOPYSIGN32(SDValue Op,SelectionDAG & DAG,bool HasExtractInsert)1914 static SDValue lowerFCOPYSIGN32(SDValue Op, SelectionDAG &DAG,
1915                                 bool HasExtractInsert) {
1916   EVT TyX = Op.getOperand(0).getValueType();
1917   EVT TyY = Op.getOperand(1).getValueType();
1918   SDLoc DL(Op);
1919   SDValue Const1 = DAG.getConstant(1, DL, MVT::i32);
1920   SDValue Const31 = DAG.getConstant(31, DL, MVT::i32);
1921   SDValue Res;
1922 
1923   // If operand is of type f64, extract the upper 32-bit. Otherwise, bitcast it
1924   // to i32.
1925   SDValue X = (TyX == MVT::f32) ?
1926     DAG.getNode(ISD::BITCAST, DL, MVT::i32, Op.getOperand(0)) :
1927     DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32, Op.getOperand(0),
1928                 Const1);
1929   SDValue Y = (TyY == MVT::f32) ?
1930     DAG.getNode(ISD::BITCAST, DL, MVT::i32, Op.getOperand(1)) :
1931     DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32, Op.getOperand(1),
1932                 Const1);
1933 
1934   if (HasExtractInsert) {
1935     // ext  E, Y, 31, 1  ; extract bit31 of Y
1936     // ins  X, E, 31, 1  ; insert extracted bit at bit31 of X
1937     SDValue E = DAG.getNode(MipsISD::Ext, DL, MVT::i32, Y, Const31, Const1);
1938     Res = DAG.getNode(MipsISD::Ins, DL, MVT::i32, E, Const31, Const1, X);
1939   } else {
1940     // sll SllX, X, 1
1941     // srl SrlX, SllX, 1
1942     // srl SrlY, Y, 31
1943     // sll SllY, SrlX, 31
1944     // or  Or, SrlX, SllY
1945     SDValue SllX = DAG.getNode(ISD::SHL, DL, MVT::i32, X, Const1);
1946     SDValue SrlX = DAG.getNode(ISD::SRL, DL, MVT::i32, SllX, Const1);
1947     SDValue SrlY = DAG.getNode(ISD::SRL, DL, MVT::i32, Y, Const31);
1948     SDValue SllY = DAG.getNode(ISD::SHL, DL, MVT::i32, SrlY, Const31);
1949     Res = DAG.getNode(ISD::OR, DL, MVT::i32, SrlX, SllY);
1950   }
1951 
1952   if (TyX == MVT::f32)
1953     return DAG.getNode(ISD::BITCAST, DL, Op.getOperand(0).getValueType(), Res);
1954 
1955   SDValue LowX = DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32,
1956                              Op.getOperand(0),
1957                              DAG.getConstant(0, DL, MVT::i32));
1958   return DAG.getNode(MipsISD::BuildPairF64, DL, MVT::f64, LowX, Res);
1959 }
1960 
lowerFCOPYSIGN64(SDValue Op,SelectionDAG & DAG,bool HasExtractInsert)1961 static SDValue lowerFCOPYSIGN64(SDValue Op, SelectionDAG &DAG,
1962                                 bool HasExtractInsert) {
1963   unsigned WidthX = Op.getOperand(0).getValueSizeInBits();
1964   unsigned WidthY = Op.getOperand(1).getValueSizeInBits();
1965   EVT TyX = MVT::getIntegerVT(WidthX), TyY = MVT::getIntegerVT(WidthY);
1966   SDLoc DL(Op);
1967   SDValue Const1 = DAG.getConstant(1, DL, MVT::i32);
1968 
1969   // Bitcast to integer nodes.
1970   SDValue X = DAG.getNode(ISD::BITCAST, DL, TyX, Op.getOperand(0));
1971   SDValue Y = DAG.getNode(ISD::BITCAST, DL, TyY, Op.getOperand(1));
1972 
1973   if (HasExtractInsert) {
1974     // ext  E, Y, width(Y) - 1, 1  ; extract bit width(Y)-1 of Y
1975     // ins  X, E, width(X) - 1, 1  ; insert extracted bit at bit width(X)-1 of X
1976     SDValue E = DAG.getNode(MipsISD::Ext, DL, TyY, Y,
1977                             DAG.getConstant(WidthY - 1, DL, MVT::i32), Const1);
1978 
1979     if (WidthX > WidthY)
1980       E = DAG.getNode(ISD::ZERO_EXTEND, DL, TyX, E);
1981     else if (WidthY > WidthX)
1982       E = DAG.getNode(ISD::TRUNCATE, DL, TyX, E);
1983 
1984     SDValue I = DAG.getNode(MipsISD::Ins, DL, TyX, E,
1985                             DAG.getConstant(WidthX - 1, DL, MVT::i32), Const1,
1986                             X);
1987     return DAG.getNode(ISD::BITCAST, DL, Op.getOperand(0).getValueType(), I);
1988   }
1989 
1990   // (d)sll SllX, X, 1
1991   // (d)srl SrlX, SllX, 1
1992   // (d)srl SrlY, Y, width(Y)-1
1993   // (d)sll SllY, SrlX, width(Y)-1
1994   // or     Or, SrlX, SllY
1995   SDValue SllX = DAG.getNode(ISD::SHL, DL, TyX, X, Const1);
1996   SDValue SrlX = DAG.getNode(ISD::SRL, DL, TyX, SllX, Const1);
1997   SDValue SrlY = DAG.getNode(ISD::SRL, DL, TyY, Y,
1998                              DAG.getConstant(WidthY - 1, DL, MVT::i32));
1999 
2000   if (WidthX > WidthY)
2001     SrlY = DAG.getNode(ISD::ZERO_EXTEND, DL, TyX, SrlY);
2002   else if (WidthY > WidthX)
2003     SrlY = DAG.getNode(ISD::TRUNCATE, DL, TyX, SrlY);
2004 
2005   SDValue SllY = DAG.getNode(ISD::SHL, DL, TyX, SrlY,
2006                              DAG.getConstant(WidthX - 1, DL, MVT::i32));
2007   SDValue Or = DAG.getNode(ISD::OR, DL, TyX, SrlX, SllY);
2008   return DAG.getNode(ISD::BITCAST, DL, Op.getOperand(0).getValueType(), Or);
2009 }
2010 
2011 SDValue
lowerFCOPYSIGN(SDValue Op,SelectionDAG & DAG) const2012 MipsTargetLowering::lowerFCOPYSIGN(SDValue Op, SelectionDAG &DAG) const {
2013   if (Subtarget.isGP64bit())
2014     return lowerFCOPYSIGN64(Op, DAG, Subtarget.hasExtractInsert());
2015 
2016   return lowerFCOPYSIGN32(Op, DAG, Subtarget.hasExtractInsert());
2017 }
2018 
2019 SDValue MipsTargetLowering::
lowerFRAMEADDR(SDValue Op,SelectionDAG & DAG) const2020 lowerFRAMEADDR(SDValue Op, SelectionDAG &DAG) const {
2021   // check the depth
2022   assert((cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue() == 0) &&
2023          "Frame address can only be determined for current frame.");
2024 
2025   MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo();
2026   MFI->setFrameAddressIsTaken(true);
2027   EVT VT = Op.getValueType();
2028   SDLoc DL(Op);
2029   SDValue FrameAddr = DAG.getCopyFromReg(
2030       DAG.getEntryNode(), DL, ABI.IsN64() ? Mips::FP_64 : Mips::FP, VT);
2031   return FrameAddr;
2032 }
2033 
lowerRETURNADDR(SDValue Op,SelectionDAG & DAG) const2034 SDValue MipsTargetLowering::lowerRETURNADDR(SDValue Op,
2035                                             SelectionDAG &DAG) const {
2036   if (verifyReturnAddressArgumentIsConstant(Op, DAG))
2037     return SDValue();
2038 
2039   // check the depth
2040   assert((cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue() == 0) &&
2041          "Return address can be determined only for current frame.");
2042 
2043   MachineFunction &MF = DAG.getMachineFunction();
2044   MachineFrameInfo *MFI = MF.getFrameInfo();
2045   MVT VT = Op.getSimpleValueType();
2046   unsigned RA = ABI.IsN64() ? Mips::RA_64 : Mips::RA;
2047   MFI->setReturnAddressIsTaken(true);
2048 
2049   // Return RA, which contains the return address. Mark it an implicit live-in.
2050   unsigned Reg = MF.addLiveIn(RA, getRegClassFor(VT));
2051   return DAG.getCopyFromReg(DAG.getEntryNode(), SDLoc(Op), Reg, VT);
2052 }
2053 
2054 // An EH_RETURN is the result of lowering llvm.eh.return which in turn is
2055 // generated from __builtin_eh_return (offset, handler)
2056 // The effect of this is to adjust the stack pointer by "offset"
2057 // and then branch to "handler".
lowerEH_RETURN(SDValue Op,SelectionDAG & DAG) const2058 SDValue MipsTargetLowering::lowerEH_RETURN(SDValue Op, SelectionDAG &DAG)
2059                                                                      const {
2060   MachineFunction &MF = DAG.getMachineFunction();
2061   MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
2062 
2063   MipsFI->setCallsEhReturn();
2064   SDValue Chain     = Op.getOperand(0);
2065   SDValue Offset    = Op.getOperand(1);
2066   SDValue Handler   = Op.getOperand(2);
2067   SDLoc DL(Op);
2068   EVT Ty = ABI.IsN64() ? MVT::i64 : MVT::i32;
2069 
2070   // Store stack offset in V1, store jump target in V0. Glue CopyToReg and
2071   // EH_RETURN nodes, so that instructions are emitted back-to-back.
2072   unsigned OffsetReg = ABI.IsN64() ? Mips::V1_64 : Mips::V1;
2073   unsigned AddrReg = ABI.IsN64() ? Mips::V0_64 : Mips::V0;
2074   Chain = DAG.getCopyToReg(Chain, DL, OffsetReg, Offset, SDValue());
2075   Chain = DAG.getCopyToReg(Chain, DL, AddrReg, Handler, Chain.getValue(1));
2076   return DAG.getNode(MipsISD::EH_RETURN, DL, MVT::Other, Chain,
2077                      DAG.getRegister(OffsetReg, Ty),
2078                      DAG.getRegister(AddrReg, getPointerTy(MF.getDataLayout())),
2079                      Chain.getValue(1));
2080 }
2081 
lowerATOMIC_FENCE(SDValue Op,SelectionDAG & DAG) const2082 SDValue MipsTargetLowering::lowerATOMIC_FENCE(SDValue Op,
2083                                               SelectionDAG &DAG) const {
2084   // FIXME: Need pseudo-fence for 'singlethread' fences
2085   // FIXME: Set SType for weaker fences where supported/appropriate.
2086   unsigned SType = 0;
2087   SDLoc DL(Op);
2088   return DAG.getNode(MipsISD::Sync, DL, MVT::Other, Op.getOperand(0),
2089                      DAG.getConstant(SType, DL, MVT::i32));
2090 }
2091 
lowerShiftLeftParts(SDValue Op,SelectionDAG & DAG) const2092 SDValue MipsTargetLowering::lowerShiftLeftParts(SDValue Op,
2093                                                 SelectionDAG &DAG) const {
2094   SDLoc DL(Op);
2095   MVT VT = Subtarget.isGP64bit() ? MVT::i64 : MVT::i32;
2096 
2097   SDValue Lo = Op.getOperand(0), Hi = Op.getOperand(1);
2098   SDValue Shamt = Op.getOperand(2);
2099   // if shamt < (VT.bits):
2100   //  lo = (shl lo, shamt)
2101   //  hi = (or (shl hi, shamt) (srl (srl lo, 1), ~shamt))
2102   // else:
2103   //  lo = 0
2104   //  hi = (shl lo, shamt[4:0])
2105   SDValue Not = DAG.getNode(ISD::XOR, DL, MVT::i32, Shamt,
2106                             DAG.getConstant(-1, DL, MVT::i32));
2107   SDValue ShiftRight1Lo = DAG.getNode(ISD::SRL, DL, VT, Lo,
2108                                       DAG.getConstant(1, DL, VT));
2109   SDValue ShiftRightLo = DAG.getNode(ISD::SRL, DL, VT, ShiftRight1Lo, Not);
2110   SDValue ShiftLeftHi = DAG.getNode(ISD::SHL, DL, VT, Hi, Shamt);
2111   SDValue Or = DAG.getNode(ISD::OR, DL, VT, ShiftLeftHi, ShiftRightLo);
2112   SDValue ShiftLeftLo = DAG.getNode(ISD::SHL, DL, VT, Lo, Shamt);
2113   SDValue Cond = DAG.getNode(ISD::AND, DL, MVT::i32, Shamt,
2114                              DAG.getConstant(VT.getSizeInBits(), DL, MVT::i32));
2115   Lo = DAG.getNode(ISD::SELECT, DL, VT, Cond,
2116                    DAG.getConstant(0, DL, VT), ShiftLeftLo);
2117   Hi = DAG.getNode(ISD::SELECT, DL, VT, Cond, ShiftLeftLo, Or);
2118 
2119   SDValue Ops[2] = {Lo, Hi};
2120   return DAG.getMergeValues(Ops, DL);
2121 }
2122 
lowerShiftRightParts(SDValue Op,SelectionDAG & DAG,bool IsSRA) const2123 SDValue MipsTargetLowering::lowerShiftRightParts(SDValue Op, SelectionDAG &DAG,
2124                                                  bool IsSRA) const {
2125   SDLoc DL(Op);
2126   SDValue Lo = Op.getOperand(0), Hi = Op.getOperand(1);
2127   SDValue Shamt = Op.getOperand(2);
2128   MVT VT = Subtarget.isGP64bit() ? MVT::i64 : MVT::i32;
2129 
2130   // if shamt < (VT.bits):
2131   //  lo = (or (shl (shl hi, 1), ~shamt) (srl lo, shamt))
2132   //  if isSRA:
2133   //    hi = (sra hi, shamt)
2134   //  else:
2135   //    hi = (srl hi, shamt)
2136   // else:
2137   //  if isSRA:
2138   //   lo = (sra hi, shamt[4:0])
2139   //   hi = (sra hi, 31)
2140   //  else:
2141   //   lo = (srl hi, shamt[4:0])
2142   //   hi = 0
2143   SDValue Not = DAG.getNode(ISD::XOR, DL, MVT::i32, Shamt,
2144                             DAG.getConstant(-1, DL, MVT::i32));
2145   SDValue ShiftLeft1Hi = DAG.getNode(ISD::SHL, DL, VT, Hi,
2146                                      DAG.getConstant(1, DL, VT));
2147   SDValue ShiftLeftHi = DAG.getNode(ISD::SHL, DL, VT, ShiftLeft1Hi, Not);
2148   SDValue ShiftRightLo = DAG.getNode(ISD::SRL, DL, VT, Lo, Shamt);
2149   SDValue Or = DAG.getNode(ISD::OR, DL, VT, ShiftLeftHi, ShiftRightLo);
2150   SDValue ShiftRightHi = DAG.getNode(IsSRA ? ISD::SRA : ISD::SRL,
2151                                      DL, VT, Hi, Shamt);
2152   SDValue Cond = DAG.getNode(ISD::AND, DL, MVT::i32, Shamt,
2153                              DAG.getConstant(VT.getSizeInBits(), DL, MVT::i32));
2154   SDValue Ext = DAG.getNode(ISD::SRA, DL, VT, Hi,
2155                             DAG.getConstant(VT.getSizeInBits() - 1, DL, VT));
2156   Lo = DAG.getNode(ISD::SELECT, DL, VT, Cond, ShiftRightHi, Or);
2157   Hi = DAG.getNode(ISD::SELECT, DL, VT, Cond,
2158                    IsSRA ? Ext : DAG.getConstant(0, DL, VT), ShiftRightHi);
2159 
2160   SDValue Ops[2] = {Lo, Hi};
2161   return DAG.getMergeValues(Ops, DL);
2162 }
2163 
createLoadLR(unsigned Opc,SelectionDAG & DAG,LoadSDNode * LD,SDValue Chain,SDValue Src,unsigned Offset)2164 static SDValue createLoadLR(unsigned Opc, SelectionDAG &DAG, LoadSDNode *LD,
2165                             SDValue Chain, SDValue Src, unsigned Offset) {
2166   SDValue Ptr = LD->getBasePtr();
2167   EVT VT = LD->getValueType(0), MemVT = LD->getMemoryVT();
2168   EVT BasePtrVT = Ptr.getValueType();
2169   SDLoc DL(LD);
2170   SDVTList VTList = DAG.getVTList(VT, MVT::Other);
2171 
2172   if (Offset)
2173     Ptr = DAG.getNode(ISD::ADD, DL, BasePtrVT, Ptr,
2174                       DAG.getConstant(Offset, DL, BasePtrVT));
2175 
2176   SDValue Ops[] = { Chain, Ptr, Src };
2177   return DAG.getMemIntrinsicNode(Opc, DL, VTList, Ops, MemVT,
2178                                  LD->getMemOperand());
2179 }
2180 
2181 // Expand an unaligned 32 or 64-bit integer load node.
lowerLOAD(SDValue Op,SelectionDAG & DAG) const2182 SDValue MipsTargetLowering::lowerLOAD(SDValue Op, SelectionDAG &DAG) const {
2183   LoadSDNode *LD = cast<LoadSDNode>(Op);
2184   EVT MemVT = LD->getMemoryVT();
2185 
2186   if (Subtarget.systemSupportsUnalignedAccess())
2187     return Op;
2188 
2189   // Return if load is aligned or if MemVT is neither i32 nor i64.
2190   if ((LD->getAlignment() >= MemVT.getSizeInBits() / 8) ||
2191       ((MemVT != MVT::i32) && (MemVT != MVT::i64)))
2192     return SDValue();
2193 
2194   bool IsLittle = Subtarget.isLittle();
2195   EVT VT = Op.getValueType();
2196   ISD::LoadExtType ExtType = LD->getExtensionType();
2197   SDValue Chain = LD->getChain(), Undef = DAG.getUNDEF(VT);
2198 
2199   assert((VT == MVT::i32) || (VT == MVT::i64));
2200 
2201   // Expand
2202   //  (set dst, (i64 (load baseptr)))
2203   // to
2204   //  (set tmp, (ldl (add baseptr, 7), undef))
2205   //  (set dst, (ldr baseptr, tmp))
2206   if ((VT == MVT::i64) && (ExtType == ISD::NON_EXTLOAD)) {
2207     SDValue LDL = createLoadLR(MipsISD::LDL, DAG, LD, Chain, Undef,
2208                                IsLittle ? 7 : 0);
2209     return createLoadLR(MipsISD::LDR, DAG, LD, LDL.getValue(1), LDL,
2210                         IsLittle ? 0 : 7);
2211   }
2212 
2213   SDValue LWL = createLoadLR(MipsISD::LWL, DAG, LD, Chain, Undef,
2214                              IsLittle ? 3 : 0);
2215   SDValue LWR = createLoadLR(MipsISD::LWR, DAG, LD, LWL.getValue(1), LWL,
2216                              IsLittle ? 0 : 3);
2217 
2218   // Expand
2219   //  (set dst, (i32 (load baseptr))) or
2220   //  (set dst, (i64 (sextload baseptr))) or
2221   //  (set dst, (i64 (extload baseptr)))
2222   // to
2223   //  (set tmp, (lwl (add baseptr, 3), undef))
2224   //  (set dst, (lwr baseptr, tmp))
2225   if ((VT == MVT::i32) || (ExtType == ISD::SEXTLOAD) ||
2226       (ExtType == ISD::EXTLOAD))
2227     return LWR;
2228 
2229   assert((VT == MVT::i64) && (ExtType == ISD::ZEXTLOAD));
2230 
2231   // Expand
2232   //  (set dst, (i64 (zextload baseptr)))
2233   // to
2234   //  (set tmp0, (lwl (add baseptr, 3), undef))
2235   //  (set tmp1, (lwr baseptr, tmp0))
2236   //  (set tmp2, (shl tmp1, 32))
2237   //  (set dst, (srl tmp2, 32))
2238   SDLoc DL(LD);
2239   SDValue Const32 = DAG.getConstant(32, DL, MVT::i32);
2240   SDValue SLL = DAG.getNode(ISD::SHL, DL, MVT::i64, LWR, Const32);
2241   SDValue SRL = DAG.getNode(ISD::SRL, DL, MVT::i64, SLL, Const32);
2242   SDValue Ops[] = { SRL, LWR.getValue(1) };
2243   return DAG.getMergeValues(Ops, DL);
2244 }
2245 
createStoreLR(unsigned Opc,SelectionDAG & DAG,StoreSDNode * SD,SDValue Chain,unsigned Offset)2246 static SDValue createStoreLR(unsigned Opc, SelectionDAG &DAG, StoreSDNode *SD,
2247                              SDValue Chain, unsigned Offset) {
2248   SDValue Ptr = SD->getBasePtr(), Value = SD->getValue();
2249   EVT MemVT = SD->getMemoryVT(), BasePtrVT = Ptr.getValueType();
2250   SDLoc DL(SD);
2251   SDVTList VTList = DAG.getVTList(MVT::Other);
2252 
2253   if (Offset)
2254     Ptr = DAG.getNode(ISD::ADD, DL, BasePtrVT, Ptr,
2255                       DAG.getConstant(Offset, DL, BasePtrVT));
2256 
2257   SDValue Ops[] = { Chain, Value, Ptr };
2258   return DAG.getMemIntrinsicNode(Opc, DL, VTList, Ops, MemVT,
2259                                  SD->getMemOperand());
2260 }
2261 
2262 // Expand an unaligned 32 or 64-bit integer store node.
lowerUnalignedIntStore(StoreSDNode * SD,SelectionDAG & DAG,bool IsLittle)2263 static SDValue lowerUnalignedIntStore(StoreSDNode *SD, SelectionDAG &DAG,
2264                                       bool IsLittle) {
2265   SDValue Value = SD->getValue(), Chain = SD->getChain();
2266   EVT VT = Value.getValueType();
2267 
2268   // Expand
2269   //  (store val, baseptr) or
2270   //  (truncstore val, baseptr)
2271   // to
2272   //  (swl val, (add baseptr, 3))
2273   //  (swr val, baseptr)
2274   if ((VT == MVT::i32) || SD->isTruncatingStore()) {
2275     SDValue SWL = createStoreLR(MipsISD::SWL, DAG, SD, Chain,
2276                                 IsLittle ? 3 : 0);
2277     return createStoreLR(MipsISD::SWR, DAG, SD, SWL, IsLittle ? 0 : 3);
2278   }
2279 
2280   assert(VT == MVT::i64);
2281 
2282   // Expand
2283   //  (store val, baseptr)
2284   // to
2285   //  (sdl val, (add baseptr, 7))
2286   //  (sdr val, baseptr)
2287   SDValue SDL = createStoreLR(MipsISD::SDL, DAG, SD, Chain, IsLittle ? 7 : 0);
2288   return createStoreLR(MipsISD::SDR, DAG, SD, SDL, IsLittle ? 0 : 7);
2289 }
2290 
2291 // Lower (store (fp_to_sint $fp) $ptr) to (store (TruncIntFP $fp), $ptr).
lowerFP_TO_SINT_STORE(StoreSDNode * SD,SelectionDAG & DAG)2292 static SDValue lowerFP_TO_SINT_STORE(StoreSDNode *SD, SelectionDAG &DAG) {
2293   SDValue Val = SD->getValue();
2294 
2295   if (Val.getOpcode() != ISD::FP_TO_SINT)
2296     return SDValue();
2297 
2298   EVT FPTy = EVT::getFloatingPointVT(Val.getValueSizeInBits());
2299   SDValue Tr = DAG.getNode(MipsISD::TruncIntFP, SDLoc(Val), FPTy,
2300                            Val.getOperand(0));
2301 
2302   return DAG.getStore(SD->getChain(), SDLoc(SD), Tr, SD->getBasePtr(),
2303                       SD->getPointerInfo(), SD->isVolatile(),
2304                       SD->isNonTemporal(), SD->getAlignment());
2305 }
2306 
lowerSTORE(SDValue Op,SelectionDAG & DAG) const2307 SDValue MipsTargetLowering::lowerSTORE(SDValue Op, SelectionDAG &DAG) const {
2308   StoreSDNode *SD = cast<StoreSDNode>(Op);
2309   EVT MemVT = SD->getMemoryVT();
2310 
2311   // Lower unaligned integer stores.
2312   if (!Subtarget.systemSupportsUnalignedAccess() &&
2313       (SD->getAlignment() < MemVT.getSizeInBits() / 8) &&
2314       ((MemVT == MVT::i32) || (MemVT == MVT::i64)))
2315     return lowerUnalignedIntStore(SD, DAG, Subtarget.isLittle());
2316 
2317   return lowerFP_TO_SINT_STORE(SD, DAG);
2318 }
2319 
lowerADD(SDValue Op,SelectionDAG & DAG) const2320 SDValue MipsTargetLowering::lowerADD(SDValue Op, SelectionDAG &DAG) const {
2321   if (Op->getOperand(0).getOpcode() != ISD::FRAMEADDR
2322       || cast<ConstantSDNode>
2323         (Op->getOperand(0).getOperand(0))->getZExtValue() != 0
2324       || Op->getOperand(1).getOpcode() != ISD::FRAME_TO_ARGS_OFFSET)
2325     return SDValue();
2326 
2327   // The pattern
2328   //   (add (frameaddr 0), (frame_to_args_offset))
2329   // results from lowering llvm.eh.dwarf.cfa intrinsic. Transform it to
2330   //   (add FrameObject, 0)
2331   // where FrameObject is a fixed StackObject with offset 0 which points to
2332   // the old stack pointer.
2333   MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo();
2334   EVT ValTy = Op->getValueType(0);
2335   int FI = MFI->CreateFixedObject(Op.getValueSizeInBits() / 8, 0, false);
2336   SDValue InArgsAddr = DAG.getFrameIndex(FI, ValTy);
2337   SDLoc DL(Op);
2338   return DAG.getNode(ISD::ADD, DL, ValTy, InArgsAddr,
2339                      DAG.getConstant(0, DL, ValTy));
2340 }
2341 
lowerFP_TO_SINT(SDValue Op,SelectionDAG & DAG) const2342 SDValue MipsTargetLowering::lowerFP_TO_SINT(SDValue Op,
2343                                             SelectionDAG &DAG) const {
2344   EVT FPTy = EVT::getFloatingPointVT(Op.getValueSizeInBits());
2345   SDValue Trunc = DAG.getNode(MipsISD::TruncIntFP, SDLoc(Op), FPTy,
2346                               Op.getOperand(0));
2347   return DAG.getNode(ISD::BITCAST, SDLoc(Op), Op.getValueType(), Trunc);
2348 }
2349 
2350 //===----------------------------------------------------------------------===//
2351 //                      Calling Convention Implementation
2352 //===----------------------------------------------------------------------===//
2353 
2354 //===----------------------------------------------------------------------===//
2355 // TODO: Implement a generic logic using tblgen that can support this.
2356 // Mips O32 ABI rules:
2357 // ---
2358 // i32 - Passed in A0, A1, A2, A3 and stack
2359 // f32 - Only passed in f32 registers if no int reg has been used yet to hold
2360 //       an argument. Otherwise, passed in A1, A2, A3 and stack.
2361 // f64 - Only passed in two aliased f32 registers if no int reg has been used
2362 //       yet to hold an argument. Otherwise, use A2, A3 and stack. If A1 is
2363 //       not used, it must be shadowed. If only A3 is available, shadow it and
2364 //       go to stack.
2365 //
2366 //  For vararg functions, all arguments are passed in A0, A1, A2, A3 and stack.
2367 //===----------------------------------------------------------------------===//
2368 
CC_MipsO32(unsigned ValNo,MVT ValVT,MVT LocVT,CCValAssign::LocInfo LocInfo,ISD::ArgFlagsTy ArgFlags,CCState & State,ArrayRef<MCPhysReg> F64Regs)2369 static bool CC_MipsO32(unsigned ValNo, MVT ValVT, MVT LocVT,
2370                        CCValAssign::LocInfo LocInfo, ISD::ArgFlagsTy ArgFlags,
2371                        CCState &State, ArrayRef<MCPhysReg> F64Regs) {
2372   const MipsSubtarget &Subtarget = static_cast<const MipsSubtarget &>(
2373       State.getMachineFunction().getSubtarget());
2374 
2375   static const MCPhysReg IntRegs[] = { Mips::A0, Mips::A1, Mips::A2, Mips::A3 };
2376   static const MCPhysReg F32Regs[] = { Mips::F12, Mips::F14 };
2377 
2378   // Do not process byval args here.
2379   if (ArgFlags.isByVal())
2380     return true;
2381 
2382   // Promote i8 and i16
2383   if (ArgFlags.isInReg() && !Subtarget.isLittle()) {
2384     if (LocVT == MVT::i8 || LocVT == MVT::i16 || LocVT == MVT::i32) {
2385       LocVT = MVT::i32;
2386       if (ArgFlags.isSExt())
2387         LocInfo = CCValAssign::SExtUpper;
2388       else if (ArgFlags.isZExt())
2389         LocInfo = CCValAssign::ZExtUpper;
2390       else
2391         LocInfo = CCValAssign::AExtUpper;
2392     }
2393   }
2394 
2395   // Promote i8 and i16
2396   if (LocVT == MVT::i8 || LocVT == MVT::i16) {
2397     LocVT = MVT::i32;
2398     if (ArgFlags.isSExt())
2399       LocInfo = CCValAssign::SExt;
2400     else if (ArgFlags.isZExt())
2401       LocInfo = CCValAssign::ZExt;
2402     else
2403       LocInfo = CCValAssign::AExt;
2404   }
2405 
2406   unsigned Reg;
2407 
2408   // f32 and f64 are allocated in A0, A1, A2, A3 when either of the following
2409   // is true: function is vararg, argument is 3rd or higher, there is previous
2410   // argument which is not f32 or f64.
2411   bool AllocateFloatsInIntReg = State.isVarArg() || ValNo > 1 ||
2412                                 State.getFirstUnallocated(F32Regs) != ValNo;
2413   unsigned OrigAlign = ArgFlags.getOrigAlign();
2414   bool isI64 = (ValVT == MVT::i32 && OrigAlign == 8);
2415 
2416   if (ValVT == MVT::i32 || (ValVT == MVT::f32 && AllocateFloatsInIntReg)) {
2417     Reg = State.AllocateReg(IntRegs);
2418     // If this is the first part of an i64 arg,
2419     // the allocated register must be either A0 or A2.
2420     if (isI64 && (Reg == Mips::A1 || Reg == Mips::A3))
2421       Reg = State.AllocateReg(IntRegs);
2422     LocVT = MVT::i32;
2423   } else if (ValVT == MVT::f64 && AllocateFloatsInIntReg) {
2424     // Allocate int register and shadow next int register. If first
2425     // available register is Mips::A1 or Mips::A3, shadow it too.
2426     Reg = State.AllocateReg(IntRegs);
2427     if (Reg == Mips::A1 || Reg == Mips::A3)
2428       Reg = State.AllocateReg(IntRegs);
2429     State.AllocateReg(IntRegs);
2430     LocVT = MVT::i32;
2431   } else if (ValVT.isFloatingPoint() && !AllocateFloatsInIntReg) {
2432     // we are guaranteed to find an available float register
2433     if (ValVT == MVT::f32) {
2434       Reg = State.AllocateReg(F32Regs);
2435       // Shadow int register
2436       State.AllocateReg(IntRegs);
2437     } else {
2438       Reg = State.AllocateReg(F64Regs);
2439       // Shadow int registers
2440       unsigned Reg2 = State.AllocateReg(IntRegs);
2441       if (Reg2 == Mips::A1 || Reg2 == Mips::A3)
2442         State.AllocateReg(IntRegs);
2443       State.AllocateReg(IntRegs);
2444     }
2445   } else
2446     llvm_unreachable("Cannot handle this ValVT.");
2447 
2448   if (!Reg) {
2449     unsigned Offset = State.AllocateStack(ValVT.getSizeInBits() >> 3,
2450                                           OrigAlign);
2451     State.addLoc(CCValAssign::getMem(ValNo, ValVT, Offset, LocVT, LocInfo));
2452   } else
2453     State.addLoc(CCValAssign::getReg(ValNo, ValVT, Reg, LocVT, LocInfo));
2454 
2455   return false;
2456 }
2457 
CC_MipsO32_FP32(unsigned ValNo,MVT ValVT,MVT LocVT,CCValAssign::LocInfo LocInfo,ISD::ArgFlagsTy ArgFlags,CCState & State)2458 static bool CC_MipsO32_FP32(unsigned ValNo, MVT ValVT,
2459                             MVT LocVT, CCValAssign::LocInfo LocInfo,
2460                             ISD::ArgFlagsTy ArgFlags, CCState &State) {
2461   static const MCPhysReg F64Regs[] = { Mips::D6, Mips::D7 };
2462 
2463   return CC_MipsO32(ValNo, ValVT, LocVT, LocInfo, ArgFlags, State, F64Regs);
2464 }
2465 
CC_MipsO32_FP64(unsigned ValNo,MVT ValVT,MVT LocVT,CCValAssign::LocInfo LocInfo,ISD::ArgFlagsTy ArgFlags,CCState & State)2466 static bool CC_MipsO32_FP64(unsigned ValNo, MVT ValVT,
2467                             MVT LocVT, CCValAssign::LocInfo LocInfo,
2468                             ISD::ArgFlagsTy ArgFlags, CCState &State) {
2469   static const MCPhysReg F64Regs[] = { Mips::D12_64, Mips::D14_64 };
2470 
2471   return CC_MipsO32(ValNo, ValVT, LocVT, LocInfo, ArgFlags, State, F64Regs);
2472 }
2473 
2474 static bool CC_MipsO32(unsigned ValNo, MVT ValVT, MVT LocVT,
2475                        CCValAssign::LocInfo LocInfo, ISD::ArgFlagsTy ArgFlags,
2476                        CCState &State) LLVM_ATTRIBUTE_UNUSED;
2477 
2478 #include "MipsGenCallingConv.inc"
2479 
2480 //===----------------------------------------------------------------------===//
2481 //                  Call Calling Convention Implementation
2482 //===----------------------------------------------------------------------===//
2483 
2484 // Return next O32 integer argument register.
getNextIntArgReg(unsigned Reg)2485 static unsigned getNextIntArgReg(unsigned Reg) {
2486   assert((Reg == Mips::A0) || (Reg == Mips::A2));
2487   return (Reg == Mips::A0) ? Mips::A1 : Mips::A3;
2488 }
2489 
2490 SDValue
passArgOnStack(SDValue StackPtr,unsigned Offset,SDValue Chain,SDValue Arg,SDLoc DL,bool IsTailCall,SelectionDAG & DAG) const2491 MipsTargetLowering::passArgOnStack(SDValue StackPtr, unsigned Offset,
2492                                    SDValue Chain, SDValue Arg, SDLoc DL,
2493                                    bool IsTailCall, SelectionDAG &DAG) const {
2494   if (!IsTailCall) {
2495     SDValue PtrOff =
2496         DAG.getNode(ISD::ADD, DL, getPointerTy(DAG.getDataLayout()), StackPtr,
2497                     DAG.getIntPtrConstant(Offset, DL));
2498     return DAG.getStore(Chain, DL, Arg, PtrOff, MachinePointerInfo(), false,
2499                         false, 0);
2500   }
2501 
2502   MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo();
2503   int FI = MFI->CreateFixedObject(Arg.getValueSizeInBits() / 8, Offset, false);
2504   SDValue FIN = DAG.getFrameIndex(FI, getPointerTy(DAG.getDataLayout()));
2505   return DAG.getStore(Chain, DL, Arg, FIN, MachinePointerInfo(),
2506                       /*isVolatile=*/ true, false, 0);
2507 }
2508 
2509 void MipsTargetLowering::
getOpndList(SmallVectorImpl<SDValue> & Ops,std::deque<std::pair<unsigned,SDValue>> & RegsToPass,bool IsPICCall,bool GlobalOrExternal,bool InternalLinkage,bool IsCallReloc,CallLoweringInfo & CLI,SDValue Callee,SDValue Chain) const2510 getOpndList(SmallVectorImpl<SDValue> &Ops,
2511             std::deque< std::pair<unsigned, SDValue> > &RegsToPass,
2512             bool IsPICCall, bool GlobalOrExternal, bool InternalLinkage,
2513             bool IsCallReloc, CallLoweringInfo &CLI, SDValue Callee,
2514             SDValue Chain) const {
2515   // Insert node "GP copy globalreg" before call to function.
2516   //
2517   // R_MIPS_CALL* operators (emitted when non-internal functions are called
2518   // in PIC mode) allow symbols to be resolved via lazy binding.
2519   // The lazy binding stub requires GP to point to the GOT.
2520   // Note that we don't need GP to point to the GOT for indirect calls
2521   // (when R_MIPS_CALL* is not used for the call) because Mips linker generates
2522   // lazy binding stub for a function only when R_MIPS_CALL* are the only relocs
2523   // used for the function (that is, Mips linker doesn't generate lazy binding
2524   // stub for a function whose address is taken in the program).
2525   if (IsPICCall && !InternalLinkage && IsCallReloc) {
2526     unsigned GPReg = ABI.IsN64() ? Mips::GP_64 : Mips::GP;
2527     EVT Ty = ABI.IsN64() ? MVT::i64 : MVT::i32;
2528     RegsToPass.push_back(std::make_pair(GPReg, getGlobalReg(CLI.DAG, Ty)));
2529   }
2530 
2531   // Build a sequence of copy-to-reg nodes chained together with token
2532   // chain and flag operands which copy the outgoing args into registers.
2533   // The InFlag in necessary since all emitted instructions must be
2534   // stuck together.
2535   SDValue InFlag;
2536 
2537   for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i) {
2538     Chain = CLI.DAG.getCopyToReg(Chain, CLI.DL, RegsToPass[i].first,
2539                                  RegsToPass[i].second, InFlag);
2540     InFlag = Chain.getValue(1);
2541   }
2542 
2543   // Add argument registers to the end of the list so that they are
2544   // known live into the call.
2545   for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i)
2546     Ops.push_back(CLI.DAG.getRegister(RegsToPass[i].first,
2547                                       RegsToPass[i].second.getValueType()));
2548 
2549   // Add a register mask operand representing the call-preserved registers.
2550   const TargetRegisterInfo *TRI = Subtarget.getRegisterInfo();
2551   const uint32_t *Mask =
2552       TRI->getCallPreservedMask(CLI.DAG.getMachineFunction(), CLI.CallConv);
2553   assert(Mask && "Missing call preserved mask for calling convention");
2554   if (Subtarget.inMips16HardFloat()) {
2555     if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(CLI.Callee)) {
2556       llvm::StringRef Sym = G->getGlobal()->getName();
2557       Function *F = G->getGlobal()->getParent()->getFunction(Sym);
2558       if (F && F->hasFnAttribute("__Mips16RetHelper")) {
2559         Mask = MipsRegisterInfo::getMips16RetHelperMask();
2560       }
2561     }
2562   }
2563   Ops.push_back(CLI.DAG.getRegisterMask(Mask));
2564 
2565   if (InFlag.getNode())
2566     Ops.push_back(InFlag);
2567 }
2568 
2569 /// LowerCall - functions arguments are copied from virtual regs to
2570 /// (physical regs)/(stack frame), CALLSEQ_START and CALLSEQ_END are emitted.
2571 SDValue
LowerCall(TargetLowering::CallLoweringInfo & CLI,SmallVectorImpl<SDValue> & InVals) const2572 MipsTargetLowering::LowerCall(TargetLowering::CallLoweringInfo &CLI,
2573                               SmallVectorImpl<SDValue> &InVals) const {
2574   SelectionDAG &DAG                     = CLI.DAG;
2575   SDLoc DL                              = CLI.DL;
2576   SmallVectorImpl<ISD::OutputArg> &Outs = CLI.Outs;
2577   SmallVectorImpl<SDValue> &OutVals     = CLI.OutVals;
2578   SmallVectorImpl<ISD::InputArg> &Ins   = CLI.Ins;
2579   SDValue Chain                         = CLI.Chain;
2580   SDValue Callee                        = CLI.Callee;
2581   bool &IsTailCall                      = CLI.IsTailCall;
2582   CallingConv::ID CallConv              = CLI.CallConv;
2583   bool IsVarArg                         = CLI.IsVarArg;
2584 
2585   MachineFunction &MF = DAG.getMachineFunction();
2586   MachineFrameInfo *MFI = MF.getFrameInfo();
2587   const TargetFrameLowering *TFL = Subtarget.getFrameLowering();
2588   MipsFunctionInfo *FuncInfo = MF.getInfo<MipsFunctionInfo>();
2589   bool IsPIC = getTargetMachine().getRelocationModel() == Reloc::PIC_;
2590 
2591   // Analyze operands of the call, assigning locations to each operand.
2592   SmallVector<CCValAssign, 16> ArgLocs;
2593   MipsCCState CCInfo(
2594       CallConv, IsVarArg, DAG.getMachineFunction(), ArgLocs, *DAG.getContext(),
2595       MipsCCState::getSpecialCallingConvForCallee(Callee.getNode(), Subtarget));
2596 
2597   // Allocate the reserved argument area. It seems strange to do this from the
2598   // caller side but removing it breaks the frame size calculation.
2599   CCInfo.AllocateStack(ABI.GetCalleeAllocdArgSizeInBytes(CallConv), 1);
2600 
2601   CCInfo.AnalyzeCallOperands(Outs, CC_Mips, CLI.getArgs(), Callee.getNode());
2602 
2603   // Get a count of how many bytes are to be pushed on the stack.
2604   unsigned NextStackOffset = CCInfo.getNextStackOffset();
2605 
2606   // Check if it's really possible to do a tail call.
2607   if (IsTailCall)
2608     IsTailCall = isEligibleForTailCallOptimization(
2609         CCInfo, NextStackOffset, *MF.getInfo<MipsFunctionInfo>());
2610 
2611   if (!IsTailCall && CLI.CS && CLI.CS->isMustTailCall())
2612     report_fatal_error("failed to perform tail call elimination on a call "
2613                        "site marked musttail");
2614 
2615   if (IsTailCall)
2616     ++NumTailCalls;
2617 
2618   // Chain is the output chain of the last Load/Store or CopyToReg node.
2619   // ByValChain is the output chain of the last Memcpy node created for copying
2620   // byval arguments to the stack.
2621   unsigned StackAlignment = TFL->getStackAlignment();
2622   NextStackOffset = RoundUpToAlignment(NextStackOffset, StackAlignment);
2623   SDValue NextStackOffsetVal = DAG.getIntPtrConstant(NextStackOffset, DL, true);
2624 
2625   if (!IsTailCall)
2626     Chain = DAG.getCALLSEQ_START(Chain, NextStackOffsetVal, DL);
2627 
2628   SDValue StackPtr =
2629       DAG.getCopyFromReg(Chain, DL, ABI.IsN64() ? Mips::SP_64 : Mips::SP,
2630                          getPointerTy(DAG.getDataLayout()));
2631 
2632   // With EABI is it possible to have 16 args on registers.
2633   std::deque< std::pair<unsigned, SDValue> > RegsToPass;
2634   SmallVector<SDValue, 8> MemOpChains;
2635 
2636   CCInfo.rewindByValRegsInfo();
2637 
2638   // Walk the register/memloc assignments, inserting copies/loads.
2639   for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
2640     SDValue Arg = OutVals[i];
2641     CCValAssign &VA = ArgLocs[i];
2642     MVT ValVT = VA.getValVT(), LocVT = VA.getLocVT();
2643     ISD::ArgFlagsTy Flags = Outs[i].Flags;
2644     bool UseUpperBits = false;
2645 
2646     // ByVal Arg.
2647     if (Flags.isByVal()) {
2648       unsigned FirstByValReg, LastByValReg;
2649       unsigned ByValIdx = CCInfo.getInRegsParamsProcessed();
2650       CCInfo.getInRegsParamInfo(ByValIdx, FirstByValReg, LastByValReg);
2651 
2652       assert(Flags.getByValSize() &&
2653              "ByVal args of size 0 should have been ignored by front-end.");
2654       assert(ByValIdx < CCInfo.getInRegsParamsCount());
2655       assert(!IsTailCall &&
2656              "Do not tail-call optimize if there is a byval argument.");
2657       passByValArg(Chain, DL, RegsToPass, MemOpChains, StackPtr, MFI, DAG, Arg,
2658                    FirstByValReg, LastByValReg, Flags, Subtarget.isLittle(),
2659                    VA);
2660       CCInfo.nextInRegsParam();
2661       continue;
2662     }
2663 
2664     // Promote the value if needed.
2665     switch (VA.getLocInfo()) {
2666     default:
2667       llvm_unreachable("Unknown loc info!");
2668     case CCValAssign::Full:
2669       if (VA.isRegLoc()) {
2670         if ((ValVT == MVT::f32 && LocVT == MVT::i32) ||
2671             (ValVT == MVT::f64 && LocVT == MVT::i64) ||
2672             (ValVT == MVT::i64 && LocVT == MVT::f64))
2673           Arg = DAG.getNode(ISD::BITCAST, DL, LocVT, Arg);
2674         else if (ValVT == MVT::f64 && LocVT == MVT::i32) {
2675           SDValue Lo = DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32,
2676                                    Arg, DAG.getConstant(0, DL, MVT::i32));
2677           SDValue Hi = DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32,
2678                                    Arg, DAG.getConstant(1, DL, MVT::i32));
2679           if (!Subtarget.isLittle())
2680             std::swap(Lo, Hi);
2681           unsigned LocRegLo = VA.getLocReg();
2682           unsigned LocRegHigh = getNextIntArgReg(LocRegLo);
2683           RegsToPass.push_back(std::make_pair(LocRegLo, Lo));
2684           RegsToPass.push_back(std::make_pair(LocRegHigh, Hi));
2685           continue;
2686         }
2687       }
2688       break;
2689     case CCValAssign::BCvt:
2690       Arg = DAG.getNode(ISD::BITCAST, DL, LocVT, Arg);
2691       break;
2692     case CCValAssign::SExtUpper:
2693       UseUpperBits = true;
2694       // Fallthrough
2695     case CCValAssign::SExt:
2696       Arg = DAG.getNode(ISD::SIGN_EXTEND, DL, LocVT, Arg);
2697       break;
2698     case CCValAssign::ZExtUpper:
2699       UseUpperBits = true;
2700       // Fallthrough
2701     case CCValAssign::ZExt:
2702       Arg = DAG.getNode(ISD::ZERO_EXTEND, DL, LocVT, Arg);
2703       break;
2704     case CCValAssign::AExtUpper:
2705       UseUpperBits = true;
2706       // Fallthrough
2707     case CCValAssign::AExt:
2708       Arg = DAG.getNode(ISD::ANY_EXTEND, DL, LocVT, Arg);
2709       break;
2710     }
2711 
2712     if (UseUpperBits) {
2713       unsigned ValSizeInBits = Outs[i].ArgVT.getSizeInBits();
2714       unsigned LocSizeInBits = VA.getLocVT().getSizeInBits();
2715       Arg = DAG.getNode(
2716           ISD::SHL, DL, VA.getLocVT(), Arg,
2717           DAG.getConstant(LocSizeInBits - ValSizeInBits, DL, VA.getLocVT()));
2718     }
2719 
2720     // Arguments that can be passed on register must be kept at
2721     // RegsToPass vector
2722     if (VA.isRegLoc()) {
2723       RegsToPass.push_back(std::make_pair(VA.getLocReg(), Arg));
2724       continue;
2725     }
2726 
2727     // Register can't get to this point...
2728     assert(VA.isMemLoc());
2729 
2730     // emit ISD::STORE whichs stores the
2731     // parameter value to a stack Location
2732     MemOpChains.push_back(passArgOnStack(StackPtr, VA.getLocMemOffset(),
2733                                          Chain, Arg, DL, IsTailCall, DAG));
2734   }
2735 
2736   // Transform all store nodes into one single node because all store
2737   // nodes are independent of each other.
2738   if (!MemOpChains.empty())
2739     Chain = DAG.getNode(ISD::TokenFactor, DL, MVT::Other, MemOpChains);
2740 
2741   // If the callee is a GlobalAddress/ExternalSymbol node (quite common, every
2742   // direct call is) turn it into a TargetGlobalAddress/TargetExternalSymbol
2743   // node so that legalize doesn't hack it.
2744   bool IsPICCall = (ABI.IsN64() || IsPIC); // true if calls are translated to
2745                                            // jalr $25
2746   bool GlobalOrExternal = false, InternalLinkage = false, IsCallReloc = false;
2747   SDValue CalleeLo;
2748   EVT Ty = Callee.getValueType();
2749 
2750   if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee)) {
2751     if (IsPICCall) {
2752       const GlobalValue *Val = G->getGlobal();
2753       InternalLinkage = Val->hasInternalLinkage();
2754 
2755       if (InternalLinkage)
2756         Callee = getAddrLocal(G, DL, Ty, DAG, ABI.IsN32() || ABI.IsN64());
2757       else if (LargeGOT) {
2758         Callee = getAddrGlobalLargeGOT(G, DL, Ty, DAG, MipsII::MO_CALL_HI16,
2759                                        MipsII::MO_CALL_LO16, Chain,
2760                                        FuncInfo->callPtrInfo(Val));
2761         IsCallReloc = true;
2762       } else {
2763         Callee = getAddrGlobal(G, DL, Ty, DAG, MipsII::MO_GOT_CALL, Chain,
2764                                FuncInfo->callPtrInfo(Val));
2765         IsCallReloc = true;
2766       }
2767     } else
2768       Callee = DAG.getTargetGlobalAddress(G->getGlobal(), DL,
2769                                           getPointerTy(DAG.getDataLayout()), 0,
2770                                           MipsII::MO_NO_FLAG);
2771     GlobalOrExternal = true;
2772   }
2773   else if (ExternalSymbolSDNode *S = dyn_cast<ExternalSymbolSDNode>(Callee)) {
2774     const char *Sym = S->getSymbol();
2775 
2776     if (!ABI.IsN64() && !IsPIC) // !N64 && static
2777       Callee = DAG.getTargetExternalSymbol(
2778           Sym, getPointerTy(DAG.getDataLayout()), MipsII::MO_NO_FLAG);
2779     else if (LargeGOT) {
2780       Callee = getAddrGlobalLargeGOT(S, DL, Ty, DAG, MipsII::MO_CALL_HI16,
2781                                      MipsII::MO_CALL_LO16, Chain,
2782                                      FuncInfo->callPtrInfo(Sym));
2783       IsCallReloc = true;
2784     } else { // N64 || PIC
2785       Callee = getAddrGlobal(S, DL, Ty, DAG, MipsII::MO_GOT_CALL, Chain,
2786                              FuncInfo->callPtrInfo(Sym));
2787       IsCallReloc = true;
2788     }
2789 
2790     GlobalOrExternal = true;
2791   }
2792 
2793   SmallVector<SDValue, 8> Ops(1, Chain);
2794   SDVTList NodeTys = DAG.getVTList(MVT::Other, MVT::Glue);
2795 
2796   getOpndList(Ops, RegsToPass, IsPICCall, GlobalOrExternal, InternalLinkage,
2797               IsCallReloc, CLI, Callee, Chain);
2798 
2799   if (IsTailCall)
2800     return DAG.getNode(MipsISD::TailCall, DL, MVT::Other, Ops);
2801 
2802   Chain = DAG.getNode(MipsISD::JmpLink, DL, NodeTys, Ops);
2803   SDValue InFlag = Chain.getValue(1);
2804 
2805   // Create the CALLSEQ_END node.
2806   Chain = DAG.getCALLSEQ_END(Chain, NextStackOffsetVal,
2807                              DAG.getIntPtrConstant(0, DL, true), InFlag, DL);
2808   InFlag = Chain.getValue(1);
2809 
2810   // Handle result values, copying them out of physregs into vregs that we
2811   // return.
2812   return LowerCallResult(Chain, InFlag, CallConv, IsVarArg, Ins, DL, DAG,
2813                          InVals, CLI);
2814 }
2815 
2816 /// LowerCallResult - Lower the result values of a call into the
2817 /// appropriate copies out of appropriate physical registers.
LowerCallResult(SDValue Chain,SDValue InFlag,CallingConv::ID CallConv,bool IsVarArg,const SmallVectorImpl<ISD::InputArg> & Ins,SDLoc DL,SelectionDAG & DAG,SmallVectorImpl<SDValue> & InVals,TargetLowering::CallLoweringInfo & CLI) const2818 SDValue MipsTargetLowering::LowerCallResult(
2819     SDValue Chain, SDValue InFlag, CallingConv::ID CallConv, bool IsVarArg,
2820     const SmallVectorImpl<ISD::InputArg> &Ins, SDLoc DL, SelectionDAG &DAG,
2821     SmallVectorImpl<SDValue> &InVals,
2822     TargetLowering::CallLoweringInfo &CLI) const {
2823   // Assign locations to each value returned by this call.
2824   SmallVector<CCValAssign, 16> RVLocs;
2825   MipsCCState CCInfo(CallConv, IsVarArg, DAG.getMachineFunction(), RVLocs,
2826                      *DAG.getContext());
2827   CCInfo.AnalyzeCallResult(Ins, RetCC_Mips, CLI);
2828 
2829   // Copy all of the result registers out of their specified physreg.
2830   for (unsigned i = 0; i != RVLocs.size(); ++i) {
2831     CCValAssign &VA = RVLocs[i];
2832     assert(VA.isRegLoc() && "Can only return in registers!");
2833 
2834     SDValue Val = DAG.getCopyFromReg(Chain, DL, RVLocs[i].getLocReg(),
2835                                      RVLocs[i].getLocVT(), InFlag);
2836     Chain = Val.getValue(1);
2837     InFlag = Val.getValue(2);
2838 
2839     if (VA.isUpperBitsInLoc()) {
2840       unsigned ValSizeInBits = Ins[i].ArgVT.getSizeInBits();
2841       unsigned LocSizeInBits = VA.getLocVT().getSizeInBits();
2842       unsigned Shift =
2843           VA.getLocInfo() == CCValAssign::ZExtUpper ? ISD::SRL : ISD::SRA;
2844       Val = DAG.getNode(
2845           Shift, DL, VA.getLocVT(), Val,
2846           DAG.getConstant(LocSizeInBits - ValSizeInBits, DL, VA.getLocVT()));
2847     }
2848 
2849     switch (VA.getLocInfo()) {
2850     default:
2851       llvm_unreachable("Unknown loc info!");
2852     case CCValAssign::Full:
2853       break;
2854     case CCValAssign::BCvt:
2855       Val = DAG.getNode(ISD::BITCAST, DL, VA.getValVT(), Val);
2856       break;
2857     case CCValAssign::AExt:
2858     case CCValAssign::AExtUpper:
2859       Val = DAG.getNode(ISD::TRUNCATE, DL, VA.getValVT(), Val);
2860       break;
2861     case CCValAssign::ZExt:
2862     case CCValAssign::ZExtUpper:
2863       Val = DAG.getNode(ISD::AssertZext, DL, VA.getLocVT(), Val,
2864                         DAG.getValueType(VA.getValVT()));
2865       Val = DAG.getNode(ISD::TRUNCATE, DL, VA.getValVT(), Val);
2866       break;
2867     case CCValAssign::SExt:
2868     case CCValAssign::SExtUpper:
2869       Val = DAG.getNode(ISD::AssertSext, DL, VA.getLocVT(), Val,
2870                         DAG.getValueType(VA.getValVT()));
2871       Val = DAG.getNode(ISD::TRUNCATE, DL, VA.getValVT(), Val);
2872       break;
2873     }
2874 
2875     InVals.push_back(Val);
2876   }
2877 
2878   return Chain;
2879 }
2880 
UnpackFromArgumentSlot(SDValue Val,const CCValAssign & VA,EVT ArgVT,SDLoc DL,SelectionDAG & DAG)2881 static SDValue UnpackFromArgumentSlot(SDValue Val, const CCValAssign &VA,
2882                                       EVT ArgVT, SDLoc DL, SelectionDAG &DAG) {
2883   MVT LocVT = VA.getLocVT();
2884   EVT ValVT = VA.getValVT();
2885 
2886   // Shift into the upper bits if necessary.
2887   switch (VA.getLocInfo()) {
2888   default:
2889     break;
2890   case CCValAssign::AExtUpper:
2891   case CCValAssign::SExtUpper:
2892   case CCValAssign::ZExtUpper: {
2893     unsigned ValSizeInBits = ArgVT.getSizeInBits();
2894     unsigned LocSizeInBits = VA.getLocVT().getSizeInBits();
2895     unsigned Opcode =
2896         VA.getLocInfo() == CCValAssign::ZExtUpper ? ISD::SRL : ISD::SRA;
2897     Val = DAG.getNode(
2898         Opcode, DL, VA.getLocVT(), Val,
2899         DAG.getConstant(LocSizeInBits - ValSizeInBits, DL, VA.getLocVT()));
2900     break;
2901   }
2902   }
2903 
2904   // If this is an value smaller than the argument slot size (32-bit for O32,
2905   // 64-bit for N32/N64), it has been promoted in some way to the argument slot
2906   // size. Extract the value and insert any appropriate assertions regarding
2907   // sign/zero extension.
2908   switch (VA.getLocInfo()) {
2909   default:
2910     llvm_unreachable("Unknown loc info!");
2911   case CCValAssign::Full:
2912     break;
2913   case CCValAssign::AExtUpper:
2914   case CCValAssign::AExt:
2915     Val = DAG.getNode(ISD::TRUNCATE, DL, ValVT, Val);
2916     break;
2917   case CCValAssign::SExtUpper:
2918   case CCValAssign::SExt:
2919     Val = DAG.getNode(ISD::AssertSext, DL, LocVT, Val, DAG.getValueType(ValVT));
2920     Val = DAG.getNode(ISD::TRUNCATE, DL, ValVT, Val);
2921     break;
2922   case CCValAssign::ZExtUpper:
2923   case CCValAssign::ZExt:
2924     Val = DAG.getNode(ISD::AssertZext, DL, LocVT, Val, DAG.getValueType(ValVT));
2925     Val = DAG.getNode(ISD::TRUNCATE, DL, ValVT, Val);
2926     break;
2927   case CCValAssign::BCvt:
2928     Val = DAG.getNode(ISD::BITCAST, DL, ValVT, Val);
2929     break;
2930   }
2931 
2932   return Val;
2933 }
2934 
2935 //===----------------------------------------------------------------------===//
2936 //             Formal Arguments Calling Convention Implementation
2937 //===----------------------------------------------------------------------===//
2938 /// LowerFormalArguments - transform physical registers into virtual registers
2939 /// and generate load operations for arguments places on the stack.
2940 SDValue
LowerFormalArguments(SDValue Chain,CallingConv::ID CallConv,bool IsVarArg,const SmallVectorImpl<ISD::InputArg> & Ins,SDLoc DL,SelectionDAG & DAG,SmallVectorImpl<SDValue> & InVals) const2941 MipsTargetLowering::LowerFormalArguments(SDValue Chain,
2942                                          CallingConv::ID CallConv,
2943                                          bool IsVarArg,
2944                                       const SmallVectorImpl<ISD::InputArg> &Ins,
2945                                          SDLoc DL, SelectionDAG &DAG,
2946                                          SmallVectorImpl<SDValue> &InVals)
2947                                           const {
2948   MachineFunction &MF = DAG.getMachineFunction();
2949   MachineFrameInfo *MFI = MF.getFrameInfo();
2950   MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
2951 
2952   MipsFI->setVarArgsFrameIndex(0);
2953 
2954   // Used with vargs to acumulate store chains.
2955   std::vector<SDValue> OutChains;
2956 
2957   // Assign locations to all of the incoming arguments.
2958   SmallVector<CCValAssign, 16> ArgLocs;
2959   MipsCCState CCInfo(CallConv, IsVarArg, DAG.getMachineFunction(), ArgLocs,
2960                      *DAG.getContext());
2961   CCInfo.AllocateStack(ABI.GetCalleeAllocdArgSizeInBytes(CallConv), 1);
2962   const Function *Func = DAG.getMachineFunction().getFunction();
2963   Function::const_arg_iterator FuncArg = Func->arg_begin();
2964 
2965   if (Func->hasFnAttribute("interrupt") && !Func->arg_empty())
2966     report_fatal_error(
2967         "Functions with the interrupt attribute cannot have arguments!");
2968 
2969   CCInfo.AnalyzeFormalArguments(Ins, CC_Mips_FixedArg);
2970   MipsFI->setFormalArgInfo(CCInfo.getNextStackOffset(),
2971                            CCInfo.getInRegsParamsCount() > 0);
2972 
2973   unsigned CurArgIdx = 0;
2974   CCInfo.rewindByValRegsInfo();
2975 
2976   for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
2977     CCValAssign &VA = ArgLocs[i];
2978     if (Ins[i].isOrigArg()) {
2979       std::advance(FuncArg, Ins[i].getOrigArgIndex() - CurArgIdx);
2980       CurArgIdx = Ins[i].getOrigArgIndex();
2981     }
2982     EVT ValVT = VA.getValVT();
2983     ISD::ArgFlagsTy Flags = Ins[i].Flags;
2984     bool IsRegLoc = VA.isRegLoc();
2985 
2986     if (Flags.isByVal()) {
2987       assert(Ins[i].isOrigArg() && "Byval arguments cannot be implicit");
2988       unsigned FirstByValReg, LastByValReg;
2989       unsigned ByValIdx = CCInfo.getInRegsParamsProcessed();
2990       CCInfo.getInRegsParamInfo(ByValIdx, FirstByValReg, LastByValReg);
2991 
2992       assert(Flags.getByValSize() &&
2993              "ByVal args of size 0 should have been ignored by front-end.");
2994       assert(ByValIdx < CCInfo.getInRegsParamsCount());
2995       copyByValRegs(Chain, DL, OutChains, DAG, Flags, InVals, &*FuncArg,
2996                     FirstByValReg, LastByValReg, VA, CCInfo);
2997       CCInfo.nextInRegsParam();
2998       continue;
2999     }
3000 
3001     // Arguments stored on registers
3002     if (IsRegLoc) {
3003       MVT RegVT = VA.getLocVT();
3004       unsigned ArgReg = VA.getLocReg();
3005       const TargetRegisterClass *RC = getRegClassFor(RegVT);
3006 
3007       // Transform the arguments stored on
3008       // physical registers into virtual ones
3009       unsigned Reg = addLiveIn(DAG.getMachineFunction(), ArgReg, RC);
3010       SDValue ArgValue = DAG.getCopyFromReg(Chain, DL, Reg, RegVT);
3011 
3012       ArgValue = UnpackFromArgumentSlot(ArgValue, VA, Ins[i].ArgVT, DL, DAG);
3013 
3014       // Handle floating point arguments passed in integer registers and
3015       // long double arguments passed in floating point registers.
3016       if ((RegVT == MVT::i32 && ValVT == MVT::f32) ||
3017           (RegVT == MVT::i64 && ValVT == MVT::f64) ||
3018           (RegVT == MVT::f64 && ValVT == MVT::i64))
3019         ArgValue = DAG.getNode(ISD::BITCAST, DL, ValVT, ArgValue);
3020       else if (ABI.IsO32() && RegVT == MVT::i32 &&
3021                ValVT == MVT::f64) {
3022         unsigned Reg2 = addLiveIn(DAG.getMachineFunction(),
3023                                   getNextIntArgReg(ArgReg), RC);
3024         SDValue ArgValue2 = DAG.getCopyFromReg(Chain, DL, Reg2, RegVT);
3025         if (!Subtarget.isLittle())
3026           std::swap(ArgValue, ArgValue2);
3027         ArgValue = DAG.getNode(MipsISD::BuildPairF64, DL, MVT::f64,
3028                                ArgValue, ArgValue2);
3029       }
3030 
3031       InVals.push_back(ArgValue);
3032     } else { // VA.isRegLoc()
3033       MVT LocVT = VA.getLocVT();
3034 
3035       if (ABI.IsO32()) {
3036         // We ought to be able to use LocVT directly but O32 sets it to i32
3037         // when allocating floating point values to integer registers.
3038         // This shouldn't influence how we load the value into registers unless
3039         // we are targeting softfloat.
3040         if (VA.getValVT().isFloatingPoint() && !Subtarget.useSoftFloat())
3041           LocVT = VA.getValVT();
3042       }
3043 
3044       // sanity check
3045       assert(VA.isMemLoc());
3046 
3047       // The stack pointer offset is relative to the caller stack frame.
3048       int FI = MFI->CreateFixedObject(LocVT.getSizeInBits() / 8,
3049                                       VA.getLocMemOffset(), true);
3050 
3051       // Create load nodes to retrieve arguments from the stack
3052       SDValue FIN = DAG.getFrameIndex(FI, getPointerTy(DAG.getDataLayout()));
3053       SDValue ArgValue = DAG.getLoad(
3054           LocVT, DL, Chain, FIN,
3055           MachinePointerInfo::getFixedStack(DAG.getMachineFunction(), FI),
3056           false, false, false, 0);
3057       OutChains.push_back(ArgValue.getValue(1));
3058 
3059       ArgValue = UnpackFromArgumentSlot(ArgValue, VA, Ins[i].ArgVT, DL, DAG);
3060 
3061       InVals.push_back(ArgValue);
3062     }
3063   }
3064 
3065   for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
3066     // The mips ABIs for returning structs by value requires that we copy
3067     // the sret argument into $v0 for the return. Save the argument into
3068     // a virtual register so that we can access it from the return points.
3069     if (Ins[i].Flags.isSRet()) {
3070       unsigned Reg = MipsFI->getSRetReturnReg();
3071       if (!Reg) {
3072         Reg = MF.getRegInfo().createVirtualRegister(
3073             getRegClassFor(ABI.IsN64() ? MVT::i64 : MVT::i32));
3074         MipsFI->setSRetReturnReg(Reg);
3075       }
3076       SDValue Copy = DAG.getCopyToReg(DAG.getEntryNode(), DL, Reg, InVals[i]);
3077       Chain = DAG.getNode(ISD::TokenFactor, DL, MVT::Other, Copy, Chain);
3078       break;
3079     }
3080   }
3081 
3082   if (IsVarArg)
3083     writeVarArgRegs(OutChains, Chain, DL, DAG, CCInfo);
3084 
3085   // All stores are grouped in one node to allow the matching between
3086   // the size of Ins and InVals. This only happens when on varg functions
3087   if (!OutChains.empty()) {
3088     OutChains.push_back(Chain);
3089     Chain = DAG.getNode(ISD::TokenFactor, DL, MVT::Other, OutChains);
3090   }
3091 
3092   return Chain;
3093 }
3094 
3095 //===----------------------------------------------------------------------===//
3096 //               Return Value Calling Convention Implementation
3097 //===----------------------------------------------------------------------===//
3098 
3099 bool
CanLowerReturn(CallingConv::ID CallConv,MachineFunction & MF,bool IsVarArg,const SmallVectorImpl<ISD::OutputArg> & Outs,LLVMContext & Context) const3100 MipsTargetLowering::CanLowerReturn(CallingConv::ID CallConv,
3101                                    MachineFunction &MF, bool IsVarArg,
3102                                    const SmallVectorImpl<ISD::OutputArg> &Outs,
3103                                    LLVMContext &Context) const {
3104   SmallVector<CCValAssign, 16> RVLocs;
3105   MipsCCState CCInfo(CallConv, IsVarArg, MF, RVLocs, Context);
3106   return CCInfo.CheckReturn(Outs, RetCC_Mips);
3107 }
3108 
3109 bool
shouldSignExtendTypeInLibCall(EVT Type,bool IsSigned) const3110 MipsTargetLowering::shouldSignExtendTypeInLibCall(EVT Type, bool IsSigned) const {
3111   if (Subtarget.hasMips3() && Subtarget.useSoftFloat()) {
3112     if (Type == MVT::i32)
3113       return true;
3114   }
3115   return IsSigned;
3116 }
3117 
3118 SDValue
LowerInterruptReturn(SmallVectorImpl<SDValue> & RetOps,SDLoc DL,SelectionDAG & DAG) const3119 MipsTargetLowering::LowerInterruptReturn(SmallVectorImpl<SDValue> &RetOps,
3120                                          SDLoc DL, SelectionDAG &DAG) const {
3121 
3122   MachineFunction &MF = DAG.getMachineFunction();
3123   MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
3124 
3125   MipsFI->setISR();
3126 
3127   return DAG.getNode(MipsISD::ERet, DL, MVT::Other, RetOps);
3128 }
3129 
3130 SDValue
LowerReturn(SDValue Chain,CallingConv::ID CallConv,bool IsVarArg,const SmallVectorImpl<ISD::OutputArg> & Outs,const SmallVectorImpl<SDValue> & OutVals,SDLoc DL,SelectionDAG & DAG) const3131 MipsTargetLowering::LowerReturn(SDValue Chain, CallingConv::ID CallConv,
3132                                 bool IsVarArg,
3133                                 const SmallVectorImpl<ISD::OutputArg> &Outs,
3134                                 const SmallVectorImpl<SDValue> &OutVals,
3135                                 SDLoc DL, SelectionDAG &DAG) const {
3136   // CCValAssign - represent the assignment of
3137   // the return value to a location
3138   SmallVector<CCValAssign, 16> RVLocs;
3139   MachineFunction &MF = DAG.getMachineFunction();
3140 
3141   // CCState - Info about the registers and stack slot.
3142   MipsCCState CCInfo(CallConv, IsVarArg, MF, RVLocs, *DAG.getContext());
3143 
3144   // Analyze return values.
3145   CCInfo.AnalyzeReturn(Outs, RetCC_Mips);
3146 
3147   SDValue Flag;
3148   SmallVector<SDValue, 4> RetOps(1, Chain);
3149 
3150   // Copy the result values into the output registers.
3151   for (unsigned i = 0; i != RVLocs.size(); ++i) {
3152     SDValue Val = OutVals[i];
3153     CCValAssign &VA = RVLocs[i];
3154     assert(VA.isRegLoc() && "Can only return in registers!");
3155     bool UseUpperBits = false;
3156 
3157     switch (VA.getLocInfo()) {
3158     default:
3159       llvm_unreachable("Unknown loc info!");
3160     case CCValAssign::Full:
3161       break;
3162     case CCValAssign::BCvt:
3163       Val = DAG.getNode(ISD::BITCAST, DL, VA.getLocVT(), Val);
3164       break;
3165     case CCValAssign::AExtUpper:
3166       UseUpperBits = true;
3167       // Fallthrough
3168     case CCValAssign::AExt:
3169       Val = DAG.getNode(ISD::ANY_EXTEND, DL, VA.getLocVT(), Val);
3170       break;
3171     case CCValAssign::ZExtUpper:
3172       UseUpperBits = true;
3173       // Fallthrough
3174     case CCValAssign::ZExt:
3175       Val = DAG.getNode(ISD::ZERO_EXTEND, DL, VA.getLocVT(), Val);
3176       break;
3177     case CCValAssign::SExtUpper:
3178       UseUpperBits = true;
3179       // Fallthrough
3180     case CCValAssign::SExt:
3181       Val = DAG.getNode(ISD::SIGN_EXTEND, DL, VA.getLocVT(), Val);
3182       break;
3183     }
3184 
3185     if (UseUpperBits) {
3186       unsigned ValSizeInBits = Outs[i].ArgVT.getSizeInBits();
3187       unsigned LocSizeInBits = VA.getLocVT().getSizeInBits();
3188       Val = DAG.getNode(
3189           ISD::SHL, DL, VA.getLocVT(), Val,
3190           DAG.getConstant(LocSizeInBits - ValSizeInBits, DL, VA.getLocVT()));
3191     }
3192 
3193     Chain = DAG.getCopyToReg(Chain, DL, VA.getLocReg(), Val, Flag);
3194 
3195     // Guarantee that all emitted copies are stuck together with flags.
3196     Flag = Chain.getValue(1);
3197     RetOps.push_back(DAG.getRegister(VA.getLocReg(), VA.getLocVT()));
3198   }
3199 
3200   // The mips ABIs for returning structs by value requires that we copy
3201   // the sret argument into $v0 for the return. We saved the argument into
3202   // a virtual register in the entry block, so now we copy the value out
3203   // and into $v0.
3204   if (MF.getFunction()->hasStructRetAttr()) {
3205     MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
3206     unsigned Reg = MipsFI->getSRetReturnReg();
3207 
3208     if (!Reg)
3209       llvm_unreachable("sret virtual register not created in the entry block");
3210     SDValue Val =
3211         DAG.getCopyFromReg(Chain, DL, Reg, getPointerTy(DAG.getDataLayout()));
3212     unsigned V0 = ABI.IsN64() ? Mips::V0_64 : Mips::V0;
3213 
3214     Chain = DAG.getCopyToReg(Chain, DL, V0, Val, Flag);
3215     Flag = Chain.getValue(1);
3216     RetOps.push_back(DAG.getRegister(V0, getPointerTy(DAG.getDataLayout())));
3217   }
3218 
3219   RetOps[0] = Chain;  // Update chain.
3220 
3221   // Add the flag if we have it.
3222   if (Flag.getNode())
3223     RetOps.push_back(Flag);
3224 
3225   // ISRs must use "eret".
3226   if (DAG.getMachineFunction().getFunction()->hasFnAttribute("interrupt"))
3227     return LowerInterruptReturn(RetOps, DL, DAG);
3228 
3229   // Standard return on Mips is a "jr $ra"
3230   return DAG.getNode(MipsISD::Ret, DL, MVT::Other, RetOps);
3231 }
3232 
3233 //===----------------------------------------------------------------------===//
3234 //                           Mips Inline Assembly Support
3235 //===----------------------------------------------------------------------===//
3236 
3237 /// getConstraintType - Given a constraint letter, return the type of
3238 /// constraint it is for this target.
3239 MipsTargetLowering::ConstraintType
getConstraintType(StringRef Constraint) const3240 MipsTargetLowering::getConstraintType(StringRef Constraint) const {
3241   // Mips specific constraints
3242   // GCC config/mips/constraints.md
3243   //
3244   // 'd' : An address register. Equivalent to r
3245   //       unless generating MIPS16 code.
3246   // 'y' : Equivalent to r; retained for
3247   //       backwards compatibility.
3248   // 'c' : A register suitable for use in an indirect
3249   //       jump. This will always be $25 for -mabicalls.
3250   // 'l' : The lo register. 1 word storage.
3251   // 'x' : The hilo register pair. Double word storage.
3252   if (Constraint.size() == 1) {
3253     switch (Constraint[0]) {
3254       default : break;
3255       case 'd':
3256       case 'y':
3257       case 'f':
3258       case 'c':
3259       case 'l':
3260       case 'x':
3261         return C_RegisterClass;
3262       case 'R':
3263         return C_Memory;
3264     }
3265   }
3266 
3267   if (Constraint == "ZC")
3268     return C_Memory;
3269 
3270   return TargetLowering::getConstraintType(Constraint);
3271 }
3272 
3273 /// Examine constraint type and operand type and determine a weight value.
3274 /// This object must already have been set up with the operand type
3275 /// and the current alternative constraint selected.
3276 TargetLowering::ConstraintWeight
getSingleConstraintMatchWeight(AsmOperandInfo & info,const char * constraint) const3277 MipsTargetLowering::getSingleConstraintMatchWeight(
3278     AsmOperandInfo &info, const char *constraint) const {
3279   ConstraintWeight weight = CW_Invalid;
3280   Value *CallOperandVal = info.CallOperandVal;
3281     // If we don't have a value, we can't do a match,
3282     // but allow it at the lowest weight.
3283   if (!CallOperandVal)
3284     return CW_Default;
3285   Type *type = CallOperandVal->getType();
3286   // Look at the constraint type.
3287   switch (*constraint) {
3288   default:
3289     weight = TargetLowering::getSingleConstraintMatchWeight(info, constraint);
3290     break;
3291   case 'd':
3292   case 'y':
3293     if (type->isIntegerTy())
3294       weight = CW_Register;
3295     break;
3296   case 'f': // FPU or MSA register
3297     if (Subtarget.hasMSA() && type->isVectorTy() &&
3298         cast<VectorType>(type)->getBitWidth() == 128)
3299       weight = CW_Register;
3300     else if (type->isFloatTy())
3301       weight = CW_Register;
3302     break;
3303   case 'c': // $25 for indirect jumps
3304   case 'l': // lo register
3305   case 'x': // hilo register pair
3306     if (type->isIntegerTy())
3307       weight = CW_SpecificReg;
3308     break;
3309   case 'I': // signed 16 bit immediate
3310   case 'J': // integer zero
3311   case 'K': // unsigned 16 bit immediate
3312   case 'L': // signed 32 bit immediate where lower 16 bits are 0
3313   case 'N': // immediate in the range of -65535 to -1 (inclusive)
3314   case 'O': // signed 15 bit immediate (+- 16383)
3315   case 'P': // immediate in the range of 65535 to 1 (inclusive)
3316     if (isa<ConstantInt>(CallOperandVal))
3317       weight = CW_Constant;
3318     break;
3319   case 'R':
3320     weight = CW_Memory;
3321     break;
3322   }
3323   return weight;
3324 }
3325 
3326 /// This is a helper function to parse a physical register string and split it
3327 /// into non-numeric and numeric parts (Prefix and Reg). The first boolean flag
3328 /// that is returned indicates whether parsing was successful. The second flag
3329 /// is true if the numeric part exists.
parsePhysicalReg(StringRef C,StringRef & Prefix,unsigned long long & Reg)3330 static std::pair<bool, bool> parsePhysicalReg(StringRef C, StringRef &Prefix,
3331                                               unsigned long long &Reg) {
3332   if (C.front() != '{' || C.back() != '}')
3333     return std::make_pair(false, false);
3334 
3335   // Search for the first numeric character.
3336   StringRef::const_iterator I, B = C.begin() + 1, E = C.end() - 1;
3337   I = std::find_if(B, E, isdigit);
3338 
3339   Prefix = StringRef(B, I - B);
3340 
3341   // The second flag is set to false if no numeric characters were found.
3342   if (I == E)
3343     return std::make_pair(true, false);
3344 
3345   // Parse the numeric characters.
3346   return std::make_pair(!getAsUnsignedInteger(StringRef(I, E - I), 10, Reg),
3347                         true);
3348 }
3349 
3350 std::pair<unsigned, const TargetRegisterClass *> MipsTargetLowering::
parseRegForInlineAsmConstraint(StringRef C,MVT VT) const3351 parseRegForInlineAsmConstraint(StringRef C, MVT VT) const {
3352   const TargetRegisterInfo *TRI =
3353       Subtarget.getRegisterInfo();
3354   const TargetRegisterClass *RC;
3355   StringRef Prefix;
3356   unsigned long long Reg;
3357 
3358   std::pair<bool, bool> R = parsePhysicalReg(C, Prefix, Reg);
3359 
3360   if (!R.first)
3361     return std::make_pair(0U, nullptr);
3362 
3363   if ((Prefix == "hi" || Prefix == "lo")) { // Parse hi/lo.
3364     // No numeric characters follow "hi" or "lo".
3365     if (R.second)
3366       return std::make_pair(0U, nullptr);
3367 
3368     RC = TRI->getRegClass(Prefix == "hi" ?
3369                           Mips::HI32RegClassID : Mips::LO32RegClassID);
3370     return std::make_pair(*(RC->begin()), RC);
3371   } else if (Prefix.startswith("$msa")) {
3372     // Parse $msa(ir|csr|access|save|modify|request|map|unmap)
3373 
3374     // No numeric characters follow the name.
3375     if (R.second)
3376       return std::make_pair(0U, nullptr);
3377 
3378     Reg = StringSwitch<unsigned long long>(Prefix)
3379               .Case("$msair", Mips::MSAIR)
3380               .Case("$msacsr", Mips::MSACSR)
3381               .Case("$msaaccess", Mips::MSAAccess)
3382               .Case("$msasave", Mips::MSASave)
3383               .Case("$msamodify", Mips::MSAModify)
3384               .Case("$msarequest", Mips::MSARequest)
3385               .Case("$msamap", Mips::MSAMap)
3386               .Case("$msaunmap", Mips::MSAUnmap)
3387               .Default(0);
3388 
3389     if (!Reg)
3390       return std::make_pair(0U, nullptr);
3391 
3392     RC = TRI->getRegClass(Mips::MSACtrlRegClassID);
3393     return std::make_pair(Reg, RC);
3394   }
3395 
3396   if (!R.second)
3397     return std::make_pair(0U, nullptr);
3398 
3399   if (Prefix == "$f") { // Parse $f0-$f31.
3400     // If the size of FP registers is 64-bit or Reg is an even number, select
3401     // the 64-bit register class. Otherwise, select the 32-bit register class.
3402     if (VT == MVT::Other)
3403       VT = (Subtarget.isFP64bit() || !(Reg % 2)) ? MVT::f64 : MVT::f32;
3404 
3405     RC = getRegClassFor(VT);
3406 
3407     if (RC == &Mips::AFGR64RegClass) {
3408       assert(Reg % 2 == 0);
3409       Reg >>= 1;
3410     }
3411   } else if (Prefix == "$fcc") // Parse $fcc0-$fcc7.
3412     RC = TRI->getRegClass(Mips::FCCRegClassID);
3413   else if (Prefix == "$w") { // Parse $w0-$w31.
3414     RC = getRegClassFor((VT == MVT::Other) ? MVT::v16i8 : VT);
3415   } else { // Parse $0-$31.
3416     assert(Prefix == "$");
3417     RC = getRegClassFor((VT == MVT::Other) ? MVT::i32 : VT);
3418   }
3419 
3420   assert(Reg < RC->getNumRegs());
3421   return std::make_pair(*(RC->begin() + Reg), RC);
3422 }
3423 
3424 /// Given a register class constraint, like 'r', if this corresponds directly
3425 /// to an LLVM register class, return a register of 0 and the register class
3426 /// pointer.
3427 std::pair<unsigned, const TargetRegisterClass *>
getRegForInlineAsmConstraint(const TargetRegisterInfo * TRI,StringRef Constraint,MVT VT) const3428 MipsTargetLowering::getRegForInlineAsmConstraint(const TargetRegisterInfo *TRI,
3429                                                  StringRef Constraint,
3430                                                  MVT VT) const {
3431   if (Constraint.size() == 1) {
3432     switch (Constraint[0]) {
3433     case 'd': // Address register. Same as 'r' unless generating MIPS16 code.
3434     case 'y': // Same as 'r'. Exists for compatibility.
3435     case 'r':
3436       if (VT == MVT::i32 || VT == MVT::i16 || VT == MVT::i8) {
3437         if (Subtarget.inMips16Mode())
3438           return std::make_pair(0U, &Mips::CPU16RegsRegClass);
3439         return std::make_pair(0U, &Mips::GPR32RegClass);
3440       }
3441       if (VT == MVT::i64 && !Subtarget.isGP64bit())
3442         return std::make_pair(0U, &Mips::GPR32RegClass);
3443       if (VT == MVT::i64 && Subtarget.isGP64bit())
3444         return std::make_pair(0U, &Mips::GPR64RegClass);
3445       // This will generate an error message
3446       return std::make_pair(0U, nullptr);
3447     case 'f': // FPU or MSA register
3448       if (VT == MVT::v16i8)
3449         return std::make_pair(0U, &Mips::MSA128BRegClass);
3450       else if (VT == MVT::v8i16 || VT == MVT::v8f16)
3451         return std::make_pair(0U, &Mips::MSA128HRegClass);
3452       else if (VT == MVT::v4i32 || VT == MVT::v4f32)
3453         return std::make_pair(0U, &Mips::MSA128WRegClass);
3454       else if (VT == MVT::v2i64 || VT == MVT::v2f64)
3455         return std::make_pair(0U, &Mips::MSA128DRegClass);
3456       else if (VT == MVT::f32)
3457         return std::make_pair(0U, &Mips::FGR32RegClass);
3458       else if ((VT == MVT::f64) && (!Subtarget.isSingleFloat())) {
3459         if (Subtarget.isFP64bit())
3460           return std::make_pair(0U, &Mips::FGR64RegClass);
3461         return std::make_pair(0U, &Mips::AFGR64RegClass);
3462       }
3463       break;
3464     case 'c': // register suitable for indirect jump
3465       if (VT == MVT::i32)
3466         return std::make_pair((unsigned)Mips::T9, &Mips::GPR32RegClass);
3467       assert(VT == MVT::i64 && "Unexpected type.");
3468       return std::make_pair((unsigned)Mips::T9_64, &Mips::GPR64RegClass);
3469     case 'l': // register suitable for indirect jump
3470       if (VT == MVT::i32)
3471         return std::make_pair((unsigned)Mips::LO0, &Mips::LO32RegClass);
3472       return std::make_pair((unsigned)Mips::LO0_64, &Mips::LO64RegClass);
3473     case 'x': // register suitable for indirect jump
3474       // Fixme: Not triggering the use of both hi and low
3475       // This will generate an error message
3476       return std::make_pair(0U, nullptr);
3477     }
3478   }
3479 
3480   std::pair<unsigned, const TargetRegisterClass *> R;
3481   R = parseRegForInlineAsmConstraint(Constraint, VT);
3482 
3483   if (R.second)
3484     return R;
3485 
3486   return TargetLowering::getRegForInlineAsmConstraint(TRI, Constraint, VT);
3487 }
3488 
3489 /// LowerAsmOperandForConstraint - Lower the specified operand into the Ops
3490 /// vector.  If it is invalid, don't add anything to Ops.
LowerAsmOperandForConstraint(SDValue Op,std::string & Constraint,std::vector<SDValue> & Ops,SelectionDAG & DAG) const3491 void MipsTargetLowering::LowerAsmOperandForConstraint(SDValue Op,
3492                                                      std::string &Constraint,
3493                                                      std::vector<SDValue>&Ops,
3494                                                      SelectionDAG &DAG) const {
3495   SDLoc DL(Op);
3496   SDValue Result;
3497 
3498   // Only support length 1 constraints for now.
3499   if (Constraint.length() > 1) return;
3500 
3501   char ConstraintLetter = Constraint[0];
3502   switch (ConstraintLetter) {
3503   default: break; // This will fall through to the generic implementation
3504   case 'I': // Signed 16 bit constant
3505     // If this fails, the parent routine will give an error
3506     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
3507       EVT Type = Op.getValueType();
3508       int64_t Val = C->getSExtValue();
3509       if (isInt<16>(Val)) {
3510         Result = DAG.getTargetConstant(Val, DL, Type);
3511         break;
3512       }
3513     }
3514     return;
3515   case 'J': // integer zero
3516     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
3517       EVT Type = Op.getValueType();
3518       int64_t Val = C->getZExtValue();
3519       if (Val == 0) {
3520         Result = DAG.getTargetConstant(0, DL, Type);
3521         break;
3522       }
3523     }
3524     return;
3525   case 'K': // unsigned 16 bit immediate
3526     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
3527       EVT Type = Op.getValueType();
3528       uint64_t Val = (uint64_t)C->getZExtValue();
3529       if (isUInt<16>(Val)) {
3530         Result = DAG.getTargetConstant(Val, DL, Type);
3531         break;
3532       }
3533     }
3534     return;
3535   case 'L': // signed 32 bit immediate where lower 16 bits are 0
3536     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
3537       EVT Type = Op.getValueType();
3538       int64_t Val = C->getSExtValue();
3539       if ((isInt<32>(Val)) && ((Val & 0xffff) == 0)){
3540         Result = DAG.getTargetConstant(Val, DL, Type);
3541         break;
3542       }
3543     }
3544     return;
3545   case 'N': // immediate in the range of -65535 to -1 (inclusive)
3546     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
3547       EVT Type = Op.getValueType();
3548       int64_t Val = C->getSExtValue();
3549       if ((Val >= -65535) && (Val <= -1)) {
3550         Result = DAG.getTargetConstant(Val, DL, Type);
3551         break;
3552       }
3553     }
3554     return;
3555   case 'O': // signed 15 bit immediate
3556     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
3557       EVT Type = Op.getValueType();
3558       int64_t Val = C->getSExtValue();
3559       if ((isInt<15>(Val))) {
3560         Result = DAG.getTargetConstant(Val, DL, Type);
3561         break;
3562       }
3563     }
3564     return;
3565   case 'P': // immediate in the range of 1 to 65535 (inclusive)
3566     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
3567       EVT Type = Op.getValueType();
3568       int64_t Val = C->getSExtValue();
3569       if ((Val <= 65535) && (Val >= 1)) {
3570         Result = DAG.getTargetConstant(Val, DL, Type);
3571         break;
3572       }
3573     }
3574     return;
3575   }
3576 
3577   if (Result.getNode()) {
3578     Ops.push_back(Result);
3579     return;
3580   }
3581 
3582   TargetLowering::LowerAsmOperandForConstraint(Op, Constraint, Ops, DAG);
3583 }
3584 
isLegalAddressingMode(const DataLayout & DL,const AddrMode & AM,Type * Ty,unsigned AS) const3585 bool MipsTargetLowering::isLegalAddressingMode(const DataLayout &DL,
3586                                                const AddrMode &AM, Type *Ty,
3587                                                unsigned AS) const {
3588   // No global is ever allowed as a base.
3589   if (AM.BaseGV)
3590     return false;
3591 
3592   switch (AM.Scale) {
3593   case 0: // "r+i" or just "i", depending on HasBaseReg.
3594     break;
3595   case 1:
3596     if (!AM.HasBaseReg) // allow "r+i".
3597       break;
3598     return false; // disallow "r+r" or "r+r+i".
3599   default:
3600     return false;
3601   }
3602 
3603   return true;
3604 }
3605 
3606 bool
isOffsetFoldingLegal(const GlobalAddressSDNode * GA) const3607 MipsTargetLowering::isOffsetFoldingLegal(const GlobalAddressSDNode *GA) const {
3608   // The Mips target isn't yet aware of offsets.
3609   return false;
3610 }
3611 
getOptimalMemOpType(uint64_t Size,unsigned DstAlign,unsigned SrcAlign,bool IsMemset,bool ZeroMemset,bool MemcpyStrSrc,MachineFunction & MF) const3612 EVT MipsTargetLowering::getOptimalMemOpType(uint64_t Size, unsigned DstAlign,
3613                                             unsigned SrcAlign,
3614                                             bool IsMemset, bool ZeroMemset,
3615                                             bool MemcpyStrSrc,
3616                                             MachineFunction &MF) const {
3617   if (Subtarget.hasMips64())
3618     return MVT::i64;
3619 
3620   return MVT::i32;
3621 }
3622 
isFPImmLegal(const APFloat & Imm,EVT VT) const3623 bool MipsTargetLowering::isFPImmLegal(const APFloat &Imm, EVT VT) const {
3624   if (VT != MVT::f32 && VT != MVT::f64)
3625     return false;
3626   if (Imm.isNegZero())
3627     return false;
3628   return Imm.isZero();
3629 }
3630 
getJumpTableEncoding() const3631 unsigned MipsTargetLowering::getJumpTableEncoding() const {
3632   if (ABI.IsN64())
3633     return MachineJumpTableInfo::EK_GPRel64BlockAddress;
3634 
3635   return TargetLowering::getJumpTableEncoding();
3636 }
3637 
useSoftFloat() const3638 bool MipsTargetLowering::useSoftFloat() const {
3639   return Subtarget.useSoftFloat();
3640 }
3641 
copyByValRegs(SDValue Chain,SDLoc DL,std::vector<SDValue> & OutChains,SelectionDAG & DAG,const ISD::ArgFlagsTy & Flags,SmallVectorImpl<SDValue> & InVals,const Argument * FuncArg,unsigned FirstReg,unsigned LastReg,const CCValAssign & VA,MipsCCState & State) const3642 void MipsTargetLowering::copyByValRegs(
3643     SDValue Chain, SDLoc DL, std::vector<SDValue> &OutChains, SelectionDAG &DAG,
3644     const ISD::ArgFlagsTy &Flags, SmallVectorImpl<SDValue> &InVals,
3645     const Argument *FuncArg, unsigned FirstReg, unsigned LastReg,
3646     const CCValAssign &VA, MipsCCState &State) const {
3647   MachineFunction &MF = DAG.getMachineFunction();
3648   MachineFrameInfo *MFI = MF.getFrameInfo();
3649   unsigned GPRSizeInBytes = Subtarget.getGPRSizeInBytes();
3650   unsigned NumRegs = LastReg - FirstReg;
3651   unsigned RegAreaSize = NumRegs * GPRSizeInBytes;
3652   unsigned FrameObjSize = std::max(Flags.getByValSize(), RegAreaSize);
3653   int FrameObjOffset;
3654   ArrayRef<MCPhysReg> ByValArgRegs = ABI.GetByValArgRegs();
3655 
3656   if (RegAreaSize)
3657     FrameObjOffset =
3658         (int)ABI.GetCalleeAllocdArgSizeInBytes(State.getCallingConv()) -
3659         (int)((ByValArgRegs.size() - FirstReg) * GPRSizeInBytes);
3660   else
3661     FrameObjOffset = VA.getLocMemOffset();
3662 
3663   // Create frame object.
3664   EVT PtrTy = getPointerTy(DAG.getDataLayout());
3665   int FI = MFI->CreateFixedObject(FrameObjSize, FrameObjOffset, true);
3666   SDValue FIN = DAG.getFrameIndex(FI, PtrTy);
3667   InVals.push_back(FIN);
3668 
3669   if (!NumRegs)
3670     return;
3671 
3672   // Copy arg registers.
3673   MVT RegTy = MVT::getIntegerVT(GPRSizeInBytes * 8);
3674   const TargetRegisterClass *RC = getRegClassFor(RegTy);
3675 
3676   for (unsigned I = 0; I < NumRegs; ++I) {
3677     unsigned ArgReg = ByValArgRegs[FirstReg + I];
3678     unsigned VReg = addLiveIn(MF, ArgReg, RC);
3679     unsigned Offset = I * GPRSizeInBytes;
3680     SDValue StorePtr = DAG.getNode(ISD::ADD, DL, PtrTy, FIN,
3681                                    DAG.getConstant(Offset, DL, PtrTy));
3682     SDValue Store = DAG.getStore(Chain, DL, DAG.getRegister(VReg, RegTy),
3683                                  StorePtr, MachinePointerInfo(FuncArg, Offset),
3684                                  false, false, 0);
3685     OutChains.push_back(Store);
3686   }
3687 }
3688 
3689 // Copy byVal arg to registers and stack.
passByValArg(SDValue Chain,SDLoc DL,std::deque<std::pair<unsigned,SDValue>> & RegsToPass,SmallVectorImpl<SDValue> & MemOpChains,SDValue StackPtr,MachineFrameInfo * MFI,SelectionDAG & DAG,SDValue Arg,unsigned FirstReg,unsigned LastReg,const ISD::ArgFlagsTy & Flags,bool isLittle,const CCValAssign & VA) const3690 void MipsTargetLowering::passByValArg(
3691     SDValue Chain, SDLoc DL,
3692     std::deque<std::pair<unsigned, SDValue>> &RegsToPass,
3693     SmallVectorImpl<SDValue> &MemOpChains, SDValue StackPtr,
3694     MachineFrameInfo *MFI, SelectionDAG &DAG, SDValue Arg, unsigned FirstReg,
3695     unsigned LastReg, const ISD::ArgFlagsTy &Flags, bool isLittle,
3696     const CCValAssign &VA) const {
3697   unsigned ByValSizeInBytes = Flags.getByValSize();
3698   unsigned OffsetInBytes = 0; // From beginning of struct
3699   unsigned RegSizeInBytes = Subtarget.getGPRSizeInBytes();
3700   unsigned Alignment = std::min(Flags.getByValAlign(), RegSizeInBytes);
3701   EVT PtrTy = getPointerTy(DAG.getDataLayout()),
3702       RegTy = MVT::getIntegerVT(RegSizeInBytes * 8);
3703   unsigned NumRegs = LastReg - FirstReg;
3704 
3705   if (NumRegs) {
3706     ArrayRef<MCPhysReg> ArgRegs = ABI.GetByValArgRegs();
3707     bool LeftoverBytes = (NumRegs * RegSizeInBytes > ByValSizeInBytes);
3708     unsigned I = 0;
3709 
3710     // Copy words to registers.
3711     for (; I < NumRegs - LeftoverBytes; ++I, OffsetInBytes += RegSizeInBytes) {
3712       SDValue LoadPtr = DAG.getNode(ISD::ADD, DL, PtrTy, Arg,
3713                                     DAG.getConstant(OffsetInBytes, DL, PtrTy));
3714       SDValue LoadVal = DAG.getLoad(RegTy, DL, Chain, LoadPtr,
3715                                     MachinePointerInfo(), false, false, false,
3716                                     Alignment);
3717       MemOpChains.push_back(LoadVal.getValue(1));
3718       unsigned ArgReg = ArgRegs[FirstReg + I];
3719       RegsToPass.push_back(std::make_pair(ArgReg, LoadVal));
3720     }
3721 
3722     // Return if the struct has been fully copied.
3723     if (ByValSizeInBytes == OffsetInBytes)
3724       return;
3725 
3726     // Copy the remainder of the byval argument with sub-word loads and shifts.
3727     if (LeftoverBytes) {
3728       SDValue Val;
3729 
3730       for (unsigned LoadSizeInBytes = RegSizeInBytes / 2, TotalBytesLoaded = 0;
3731            OffsetInBytes < ByValSizeInBytes; LoadSizeInBytes /= 2) {
3732         unsigned RemainingSizeInBytes = ByValSizeInBytes - OffsetInBytes;
3733 
3734         if (RemainingSizeInBytes < LoadSizeInBytes)
3735           continue;
3736 
3737         // Load subword.
3738         SDValue LoadPtr = DAG.getNode(ISD::ADD, DL, PtrTy, Arg,
3739                                       DAG.getConstant(OffsetInBytes, DL,
3740                                                       PtrTy));
3741         SDValue LoadVal = DAG.getExtLoad(
3742             ISD::ZEXTLOAD, DL, RegTy, Chain, LoadPtr, MachinePointerInfo(),
3743             MVT::getIntegerVT(LoadSizeInBytes * 8), false, false, false,
3744             Alignment);
3745         MemOpChains.push_back(LoadVal.getValue(1));
3746 
3747         // Shift the loaded value.
3748         unsigned Shamt;
3749 
3750         if (isLittle)
3751           Shamt = TotalBytesLoaded * 8;
3752         else
3753           Shamt = (RegSizeInBytes - (TotalBytesLoaded + LoadSizeInBytes)) * 8;
3754 
3755         SDValue Shift = DAG.getNode(ISD::SHL, DL, RegTy, LoadVal,
3756                                     DAG.getConstant(Shamt, DL, MVT::i32));
3757 
3758         if (Val.getNode())
3759           Val = DAG.getNode(ISD::OR, DL, RegTy, Val, Shift);
3760         else
3761           Val = Shift;
3762 
3763         OffsetInBytes += LoadSizeInBytes;
3764         TotalBytesLoaded += LoadSizeInBytes;
3765         Alignment = std::min(Alignment, LoadSizeInBytes);
3766       }
3767 
3768       unsigned ArgReg = ArgRegs[FirstReg + I];
3769       RegsToPass.push_back(std::make_pair(ArgReg, Val));
3770       return;
3771     }
3772   }
3773 
3774   // Copy remainder of byval arg to it with memcpy.
3775   unsigned MemCpySize = ByValSizeInBytes - OffsetInBytes;
3776   SDValue Src = DAG.getNode(ISD::ADD, DL, PtrTy, Arg,
3777                             DAG.getConstant(OffsetInBytes, DL, PtrTy));
3778   SDValue Dst = DAG.getNode(ISD::ADD, DL, PtrTy, StackPtr,
3779                             DAG.getIntPtrConstant(VA.getLocMemOffset(), DL));
3780   Chain = DAG.getMemcpy(Chain, DL, Dst, Src,
3781                         DAG.getConstant(MemCpySize, DL, PtrTy),
3782                         Alignment, /*isVolatile=*/false, /*AlwaysInline=*/false,
3783                         /*isTailCall=*/false,
3784                         MachinePointerInfo(), MachinePointerInfo());
3785   MemOpChains.push_back(Chain);
3786 }
3787 
writeVarArgRegs(std::vector<SDValue> & OutChains,SDValue Chain,SDLoc DL,SelectionDAG & DAG,CCState & State) const3788 void MipsTargetLowering::writeVarArgRegs(std::vector<SDValue> &OutChains,
3789                                          SDValue Chain, SDLoc DL,
3790                                          SelectionDAG &DAG,
3791                                          CCState &State) const {
3792   ArrayRef<MCPhysReg> ArgRegs = ABI.GetVarArgRegs();
3793   unsigned Idx = State.getFirstUnallocated(ArgRegs);
3794   unsigned RegSizeInBytes = Subtarget.getGPRSizeInBytes();
3795   MVT RegTy = MVT::getIntegerVT(RegSizeInBytes * 8);
3796   const TargetRegisterClass *RC = getRegClassFor(RegTy);
3797   MachineFunction &MF = DAG.getMachineFunction();
3798   MachineFrameInfo *MFI = MF.getFrameInfo();
3799   MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
3800 
3801   // Offset of the first variable argument from stack pointer.
3802   int VaArgOffset;
3803 
3804   if (ArgRegs.size() == Idx)
3805     VaArgOffset =
3806         RoundUpToAlignment(State.getNextStackOffset(), RegSizeInBytes);
3807   else {
3808     VaArgOffset =
3809         (int)ABI.GetCalleeAllocdArgSizeInBytes(State.getCallingConv()) -
3810         (int)(RegSizeInBytes * (ArgRegs.size() - Idx));
3811   }
3812 
3813   // Record the frame index of the first variable argument
3814   // which is a value necessary to VASTART.
3815   int FI = MFI->CreateFixedObject(RegSizeInBytes, VaArgOffset, true);
3816   MipsFI->setVarArgsFrameIndex(FI);
3817 
3818   // Copy the integer registers that have not been used for argument passing
3819   // to the argument register save area. For O32, the save area is allocated
3820   // in the caller's stack frame, while for N32/64, it is allocated in the
3821   // callee's stack frame.
3822   for (unsigned I = Idx; I < ArgRegs.size();
3823        ++I, VaArgOffset += RegSizeInBytes) {
3824     unsigned Reg = addLiveIn(MF, ArgRegs[I], RC);
3825     SDValue ArgValue = DAG.getCopyFromReg(Chain, DL, Reg, RegTy);
3826     FI = MFI->CreateFixedObject(RegSizeInBytes, VaArgOffset, true);
3827     SDValue PtrOff = DAG.getFrameIndex(FI, getPointerTy(DAG.getDataLayout()));
3828     SDValue Store = DAG.getStore(Chain, DL, ArgValue, PtrOff,
3829                                  MachinePointerInfo(), false, false, 0);
3830     cast<StoreSDNode>(Store.getNode())->getMemOperand()->setValue(
3831         (Value *)nullptr);
3832     OutChains.push_back(Store);
3833   }
3834 }
3835 
HandleByVal(CCState * State,unsigned & Size,unsigned Align) const3836 void MipsTargetLowering::HandleByVal(CCState *State, unsigned &Size,
3837                                      unsigned Align) const {
3838   const TargetFrameLowering *TFL = Subtarget.getFrameLowering();
3839 
3840   assert(Size && "Byval argument's size shouldn't be 0.");
3841 
3842   Align = std::min(Align, TFL->getStackAlignment());
3843 
3844   unsigned FirstReg = 0;
3845   unsigned NumRegs = 0;
3846 
3847   if (State->getCallingConv() != CallingConv::Fast) {
3848     unsigned RegSizeInBytes = Subtarget.getGPRSizeInBytes();
3849     ArrayRef<MCPhysReg> IntArgRegs = ABI.GetByValArgRegs();
3850     // FIXME: The O32 case actually describes no shadow registers.
3851     const MCPhysReg *ShadowRegs =
3852         ABI.IsO32() ? IntArgRegs.data() : Mips64DPRegs;
3853 
3854     // We used to check the size as well but we can't do that anymore since
3855     // CCState::HandleByVal() rounds up the size after calling this function.
3856     assert(!(Align % RegSizeInBytes) &&
3857            "Byval argument's alignment should be a multiple of"
3858            "RegSizeInBytes.");
3859 
3860     FirstReg = State->getFirstUnallocated(IntArgRegs);
3861 
3862     // If Align > RegSizeInBytes, the first arg register must be even.
3863     // FIXME: This condition happens to do the right thing but it's not the
3864     //        right way to test it. We want to check that the stack frame offset
3865     //        of the register is aligned.
3866     if ((Align > RegSizeInBytes) && (FirstReg % 2)) {
3867       State->AllocateReg(IntArgRegs[FirstReg], ShadowRegs[FirstReg]);
3868       ++FirstReg;
3869     }
3870 
3871     // Mark the registers allocated.
3872     Size = RoundUpToAlignment(Size, RegSizeInBytes);
3873     for (unsigned I = FirstReg; Size > 0 && (I < IntArgRegs.size());
3874          Size -= RegSizeInBytes, ++I, ++NumRegs)
3875       State->AllocateReg(IntArgRegs[I], ShadowRegs[I]);
3876   }
3877 
3878   State->addInRegsParamInfo(FirstReg, FirstReg + NumRegs);
3879 }
3880 
3881 MachineBasicBlock *
emitPseudoSELECT(MachineInstr * MI,MachineBasicBlock * BB,bool isFPCmp,unsigned Opc) const3882 MipsTargetLowering::emitPseudoSELECT(MachineInstr *MI, MachineBasicBlock *BB,
3883                                      bool isFPCmp, unsigned Opc) const {
3884   assert(!(Subtarget.hasMips4() || Subtarget.hasMips32()) &&
3885          "Subtarget already supports SELECT nodes with the use of"
3886          "conditional-move instructions.");
3887 
3888   const TargetInstrInfo *TII =
3889       Subtarget.getInstrInfo();
3890   DebugLoc DL = MI->getDebugLoc();
3891 
3892   // To "insert" a SELECT instruction, we actually have to insert the
3893   // diamond control-flow pattern.  The incoming instruction knows the
3894   // destination vreg to set, the condition code register to branch on, the
3895   // true/false values to select between, and a branch opcode to use.
3896   const BasicBlock *LLVM_BB = BB->getBasicBlock();
3897   MachineFunction::iterator It = ++BB->getIterator();
3898 
3899   //  thisMBB:
3900   //  ...
3901   //   TrueVal = ...
3902   //   setcc r1, r2, r3
3903   //   bNE   r1, r0, copy1MBB
3904   //   fallthrough --> copy0MBB
3905   MachineBasicBlock *thisMBB  = BB;
3906   MachineFunction *F = BB->getParent();
3907   MachineBasicBlock *copy0MBB = F->CreateMachineBasicBlock(LLVM_BB);
3908   MachineBasicBlock *sinkMBB  = F->CreateMachineBasicBlock(LLVM_BB);
3909   F->insert(It, copy0MBB);
3910   F->insert(It, sinkMBB);
3911 
3912   // Transfer the remainder of BB and its successor edges to sinkMBB.
3913   sinkMBB->splice(sinkMBB->begin(), BB,
3914                   std::next(MachineBasicBlock::iterator(MI)), BB->end());
3915   sinkMBB->transferSuccessorsAndUpdatePHIs(BB);
3916 
3917   // Next, add the true and fallthrough blocks as its successors.
3918   BB->addSuccessor(copy0MBB);
3919   BB->addSuccessor(sinkMBB);
3920 
3921   if (isFPCmp) {
3922     // bc1[tf] cc, sinkMBB
3923     BuildMI(BB, DL, TII->get(Opc))
3924       .addReg(MI->getOperand(1).getReg())
3925       .addMBB(sinkMBB);
3926   } else {
3927     // bne rs, $0, sinkMBB
3928     BuildMI(BB, DL, TII->get(Opc))
3929       .addReg(MI->getOperand(1).getReg())
3930       .addReg(Mips::ZERO)
3931       .addMBB(sinkMBB);
3932   }
3933 
3934   //  copy0MBB:
3935   //   %FalseValue = ...
3936   //   # fallthrough to sinkMBB
3937   BB = copy0MBB;
3938 
3939   // Update machine-CFG edges
3940   BB->addSuccessor(sinkMBB);
3941 
3942   //  sinkMBB:
3943   //   %Result = phi [ %TrueValue, thisMBB ], [ %FalseValue, copy0MBB ]
3944   //  ...
3945   BB = sinkMBB;
3946 
3947   BuildMI(*BB, BB->begin(), DL,
3948           TII->get(Mips::PHI), MI->getOperand(0).getReg())
3949     .addReg(MI->getOperand(2).getReg()).addMBB(thisMBB)
3950     .addReg(MI->getOperand(3).getReg()).addMBB(copy0MBB);
3951 
3952   MI->eraseFromParent();   // The pseudo instruction is gone now.
3953 
3954   return BB;
3955 }
3956 
3957 // FIXME? Maybe this could be a TableGen attribute on some registers and
3958 // this table could be generated automatically from RegInfo.
getRegisterByName(const char * RegName,EVT VT,SelectionDAG & DAG) const3959 unsigned MipsTargetLowering::getRegisterByName(const char* RegName, EVT VT,
3960                                                SelectionDAG &DAG) const {
3961   // Named registers is expected to be fairly rare. For now, just support $28
3962   // since the linux kernel uses it.
3963   if (Subtarget.isGP64bit()) {
3964     unsigned Reg = StringSwitch<unsigned>(RegName)
3965                          .Case("$28", Mips::GP_64)
3966                          .Default(0);
3967     if (Reg)
3968       return Reg;
3969   } else {
3970     unsigned Reg = StringSwitch<unsigned>(RegName)
3971                          .Case("$28", Mips::GP)
3972                          .Default(0);
3973     if (Reg)
3974       return Reg;
3975   }
3976   report_fatal_error("Invalid register name global variable");
3977 }
3978