lldb/source/Plugins/ABI/PowerPC/ABISysV_ppc64.cpp

   1 //===-- ABISysV_ppc64.cpp -------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "ABISysV_ppc64.h"
  10
  11 #include "llvm/ADT/STLExtras.h"
  12 #include "llvm/TargetParser/Triple.h"
  13
  14 #include "Plugins/TypeSystem/Clang/TypeSystemClang.h"
  15 #include "Utility/PPC64LE_DWARF_Registers.h"
  16 #include "Utility/PPC64_DWARF_Registers.h"
  17 #include "lldb/Core/Module.h"
  18 #include "lldb/Core/PluginManager.h"
  19 #include "lldb/Core/Value.h"
  20 #include "lldb/Core/ValueObjectConstResult.h"
  21 #include "lldb/Core/ValueObjectMemory.h"
  22 #include "lldb/Core/ValueObjectRegister.h"
  23 #include "lldb/Symbol/UnwindPlan.h"
  24 #include "lldb/Target/Process.h"
  25 #include "lldb/Target/RegisterContext.h"
  26 #include "lldb/Target/StackFrame.h"
  27 #include "lldb/Target/Target.h"
  28 #include "lldb/Target/Thread.h"
  29 #include "lldb/Utility/ConstString.h"
  30 #include "lldb/Utility/DataExtractor.h"
  31 #include "lldb/Utility/LLDBLog.h"
  32 #include "lldb/Utility/Log.h"
  33 #include "lldb/Utility/RegisterValue.h"
  34 #include "lldb/Utility/Status.h"
  35
  36 #include "clang/AST/ASTContext.h"
  37 #include "clang/AST/Attr.h"
  38 #include "clang/AST/Decl.h"
  39
  40 #define DECLARE_REGISTER_INFOS_PPC64_STRUCT
  41 #include "Plugins/Process/Utility/RegisterInfos_ppc64.h"
  42 #undef DECLARE_REGISTER_INFOS_PPC64_STRUCT
  43
  44 #define DECLARE_REGISTER_INFOS_PPC64LE_STRUCT
  45 #include "Plugins/Process/Utility/RegisterInfos_ppc64le.h"
  46 #undef DECLARE_REGISTER_INFOS_PPC64LE_STRUCT
  47 #include <optional>
  48
  49 using namespace lldb;
  50 using namespace lldb_private;
  51
  52 LLDB_PLUGIN_DEFINE(ABISysV_ppc64)
  53
  54 const lldb_private::RegisterInfo *
  55 ABISysV_ppc64::GetRegisterInfoArray(uint32_t &count) {
  56   if (GetByteOrder() == lldb::eByteOrderLittle) {
  57     count = std::size(g_register_infos_ppc64le);
  58     return g_register_infos_ppc64le;
  59   } else {
  60     count = std::size(g_register_infos_ppc64);
  61     return g_register_infos_ppc64;
  62   }
  63 }
  64
  65 size_t ABISysV_ppc64::GetRedZoneSize() const { return 224; }
  66
  67 lldb::ByteOrder ABISysV_ppc64::GetByteOrder() const {
  68   return GetProcessSP()->GetByteOrder();
  69 }
  70
  71 // Static Functions
  72
  73 ABISP
  74 ABISysV_ppc64::CreateInstance(lldb::ProcessSP process_sp,
  75                               const ArchSpec &arch) {
  76   if (arch.GetTriple().isPPC64())
  77     return ABISP(
  78         new ABISysV_ppc64(std::move(process_sp), MakeMCRegisterInfo(arch)));
  79   return ABISP();
  80 }
  81
  82 bool ABISysV_ppc64::PrepareTrivialCall(Thread &thread, addr_t sp,
  83                                        addr_t func_addr, addr_t return_addr,
  84                                        llvm::ArrayRef<addr_t> args) const {
  85   Log *log = GetLog(LLDBLog::Expressions);
  86
  87   if (log) {
  88     StreamString s;
  89     s.Printf("ABISysV_ppc64::PrepareTrivialCall (tid = 0x%" PRIx64
  90              ", sp = 0x%" PRIx64 ", func_addr = 0x%" PRIx64
  91              ", return_addr = 0x%" PRIx64,
  92              thread.GetID(), (uint64_t)sp, (uint64_t)func_addr,
  93              (uint64_t)return_addr);
  94
  95     for (size_t i = 0; i < args.size(); ++i)
  96       s.Printf(", arg%" PRIu64 " = 0x%" PRIx64, static_cast<uint64_t>(i + 1),
  97                args[i]);
  98     s.PutCString(")");
  99     log->PutString(s.GetString());
 100   }
 101
 102   RegisterContext *reg_ctx = thread.GetRegisterContext().get();
 103   if (!reg_ctx)
 104     return false;
 105
 106   const RegisterInfo *reg_info = nullptr;
 107
 108   if (args.size() > 8) // TODO handle more than 8 arguments
 109     return false;
 110
 111   for (size_t i = 0; i < args.size(); ++i) {
 112     reg_info = reg_ctx->GetRegisterInfo(eRegisterKindGeneric,
 113                                         LLDB_REGNUM_GENERIC_ARG1 + i);
 114     LLDB_LOGF(log, "About to write arg%" PRIu64 " (0x%" PRIx64 ") into %s",
 115               static_cast<uint64_t>(i + 1), args[i], reg_info->name);
 116     if (!reg_ctx->WriteRegisterFromUnsigned(reg_info, args[i]))
 117       return false;
 118   }
 119
 120   // First, align the SP
 121
 122   LLDB_LOGF(log, "16-byte aligning SP: 0x%" PRIx64 " to 0x%" PRIx64,
 123             (uint64_t)sp, (uint64_t)(sp & ~0xfull));
 124
 125   sp &= ~(0xfull); // 16-byte alignment
 126
 127   sp -= 544; // allocate frame to save TOC, RA and SP.
 128
 129   Status error;
 130   uint64_t reg_value;
 131   const RegisterInfo *pc_reg_info =
 132       reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC);
 133   const RegisterInfo *sp_reg_info =
 134       reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP);
 135   ProcessSP process_sp(thread.GetProcess());
 136   const RegisterInfo *lr_reg_info =
 137       reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_RA);
 138   const RegisterInfo *r2_reg_info = reg_ctx->GetRegisterInfoAtIndex(2);
 139   const RegisterInfo *r12_reg_info = reg_ctx->GetRegisterInfoAtIndex(12);
 140
 141   // Save return address onto the stack.
 142   LLDB_LOGF(log,
 143             "Pushing the return address onto the stack: 0x%" PRIx64
 144             "(+16): 0x%" PRIx64,
 145             (uint64_t)sp, (uint64_t)return_addr);
 146   if (!process_sp->WritePointerToMemory(sp + 16, return_addr, error))
 147     return false;
 148
 149   // Write the return address to link register.
 150   LLDB_LOGF(log, "Writing LR: 0x%" PRIx64, (uint64_t)return_addr);
 151   if (!reg_ctx->WriteRegisterFromUnsigned(lr_reg_info, return_addr))
 152     return false;
 153
 154   // Write target address to %r12 register.
 155   LLDB_LOGF(log, "Writing R12: 0x%" PRIx64, (uint64_t)func_addr);
 156   if (!reg_ctx->WriteRegisterFromUnsigned(r12_reg_info, func_addr))
 157     return false;
 158
 159   // Read TOC pointer value.
 160   reg_value = reg_ctx->ReadRegisterAsUnsigned(r2_reg_info, 0);
 161
 162   // Write TOC pointer onto the stack.
 163   uint64_t stack_offset;
 164   if (GetByteOrder() == lldb::eByteOrderLittle)
 165     stack_offset = 24;
 166   else
 167     stack_offset = 40;
 168
 169   LLDB_LOGF(log, "Writing R2 (TOC) at SP(0x%" PRIx64 ")+%d: 0x%" PRIx64,
 170             (uint64_t)(sp + stack_offset), (int)stack_offset,
 171             (uint64_t)reg_value);
 172   if (!process_sp->WritePointerToMemory(sp + stack_offset, reg_value, error))
 173     return false;
 174
 175   // Read the current SP value.
 176   reg_value = reg_ctx->ReadRegisterAsUnsigned(sp_reg_info, 0);
 177
 178   // Save current SP onto the stack.
 179   LLDB_LOGF(log, "Writing SP at SP(0x%" PRIx64 ")+0: 0x%" PRIx64, (uint64_t)sp,
 180             (uint64_t)reg_value);
 181   if (!process_sp->WritePointerToMemory(sp, reg_value, error))
 182     return false;
 183
 184   // %r1 is set to the actual stack value.
 185   LLDB_LOGF(log, "Writing SP: 0x%" PRIx64, (uint64_t)sp);
 186
 187   if (!reg_ctx->WriteRegisterFromUnsigned(sp_reg_info, sp))
 188     return false;
 189
 190   // %pc is set to the address of the called function.
 191
 192   LLDB_LOGF(log, "Writing IP: 0x%" PRIx64, (uint64_t)func_addr);
 193
 194   if (!reg_ctx->WriteRegisterFromUnsigned(pc_reg_info, func_addr))
 195     return false;
 196
 197   return true;
 198 }
 199
 200 static bool ReadIntegerArgument(Scalar &scalar, unsigned int bit_width,
 201                                 bool is_signed, Thread &thread,
 202                                 uint32_t *argument_register_ids,
 203                                 unsigned int &current_argument_register,
 204                                 addr_t &current_stack_argument) {
 205   if (bit_width > 64)
 206     return false; // Scalar can't hold large integer arguments
 207
 208   if (current_argument_register < 6) {
 209     scalar = thread.GetRegisterContext()->ReadRegisterAsUnsigned(
 210         argument_register_ids[current_argument_register], 0);
 211     current_argument_register++;
 212     if (is_signed)
 213       scalar.SignExtend(bit_width);
 214   } else {
 215     uint32_t byte_size = (bit_width + (8 - 1)) / 8;
 216     Status error;
 217     if (thread.GetProcess()->ReadScalarIntegerFromMemory(
 218             current_stack_argument, byte_size, is_signed, scalar, error)) {
 219       current_stack_argument += byte_size;
 220       return true;
 221     }
 222     return false;
 223   }
 224   return true;
 225 }
 226
 227 bool ABISysV_ppc64::GetArgumentValues(Thread &thread, ValueList &values) const {
 228   unsigned int num_values = values.GetSize();
 229   unsigned int value_index;
 230
 231   // Extract the register context so we can read arguments from registers
 232
 233   RegisterContext *reg_ctx = thread.GetRegisterContext().get();
 234
 235   if (!reg_ctx)
 236     return false;
 237
 238   // Get the pointer to the first stack argument so we have a place to start
 239   // when reading data
 240
 241   addr_t sp = reg_ctx->GetSP(0);
 242
 243   if (!sp)
 244     return false;
 245
 246   uint64_t stack_offset;
 247   if (GetByteOrder() == lldb::eByteOrderLittle)
 248     stack_offset = 32;
 249   else
 250     stack_offset = 48;
 251
 252   // jump over return address.
 253   addr_t current_stack_argument = sp + stack_offset;
 254   uint32_t argument_register_ids[8];
 255
 256   for (size_t i = 0; i < 8; ++i) {
 257     argument_register_ids[i] =
 258         reg_ctx
 259             ->GetRegisterInfo(eRegisterKindGeneric,
 260                               LLDB_REGNUM_GENERIC_ARG1 + i)
 261             ->kinds[eRegisterKindLLDB];
 262   }
 263
 264   unsigned int current_argument_register = 0;
 265
 266   for (value_index = 0; value_index < num_values; ++value_index) {
 267     Value *value = values.GetValueAtIndex(value_index);
 268
 269     if (!value)
 270       return false;
 271
 272     // We currently only support extracting values with Clang QualTypes. Do we
 273     // care about others?
 274     CompilerType compiler_type = value->GetCompilerType();
 275     std::optional<uint64_t> bit_size = compiler_type.GetBitSize(&thread);
 276     if (!bit_size)
 277       return false;
 278     bool is_signed;
 279
 280     if (compiler_type.IsIntegerOrEnumerationType(is_signed)) {
 281       ReadIntegerArgument(value->GetScalar(), *bit_size, is_signed, thread,
 282                           argument_register_ids, current_argument_register,
 283                           current_stack_argument);
 284     } else if (compiler_type.IsPointerType()) {
 285       ReadIntegerArgument(value->GetScalar(), *bit_size, false, thread,
 286                           argument_register_ids, current_argument_register,
 287                           current_stack_argument);
 288     }
 289   }
 290
 291   return true;
 292 }
 293
 294 Status ABISysV_ppc64::SetReturnValueObject(lldb::StackFrameSP &frame_sp,
 295                                            lldb::ValueObjectSP &new_value_sp) {
 296   Status error;
 297   if (!new_value_sp) {
 298     error.SetErrorString("Empty value object for return value.");
 299     return error;
 300   }
 301
 302   CompilerType compiler_type = new_value_sp->GetCompilerType();
 303   if (!compiler_type) {
 304     error.SetErrorString("Null clang type for return value.");
 305     return error;
 306   }
 307
 308   Thread *thread = frame_sp->GetThread().get();
 309
 310   bool is_signed;
 311   uint32_t count;
 312   bool is_complex;
 313
 314   RegisterContext *reg_ctx = thread->GetRegisterContext().get();
 315
 316   bool set_it_simple = false;
 317   if (compiler_type.IsIntegerOrEnumerationType(is_signed) ||
 318       compiler_type.IsPointerType()) {
 319     const RegisterInfo *reg_info = reg_ctx->GetRegisterInfoByName("r3", 0);
 320
 321     DataExtractor data;
 322     Status data_error;
 323     size_t num_bytes = new_value_sp->GetData(data, data_error);
 324     if (data_error.Fail()) {
 325       error.SetErrorStringWithFormat(
 326           "Couldn't convert return value to raw data: %s",
 327           data_error.AsCString());
 328       return error;
 329     }
 330     lldb::offset_t offset = 0;
 331     if (num_bytes <= 8) {
 332       uint64_t raw_value = data.GetMaxU64(&offset, num_bytes);
 333
 334       if (reg_ctx->WriteRegisterFromUnsigned(reg_info, raw_value))
 335         set_it_simple = true;
 336     } else {
 337       error.SetErrorString("We don't support returning longer than 64 bit "
 338                            "integer values at present.");
 339     }
 340   } else if (compiler_type.IsFloatingPointType(count, is_complex)) {
 341     if (is_complex)
 342       error.SetErrorString(
 343           "We don't support returning complex values at present");
 344     else {
 345       std::optional<uint64_t> bit_width =
 346           compiler_type.GetBitSize(frame_sp.get());
 347       if (!bit_width) {
 348         error.SetErrorString("can't get size of type");
 349         return error;
 350       }
 351       if (*bit_width <= 64) {
 352         DataExtractor data;
 353         Status data_error;
 354         size_t num_bytes = new_value_sp->GetData(data, data_error);
 355         if (data_error.Fail()) {
 356           error.SetErrorStringWithFormat(
 357               "Couldn't convert return value to raw data: %s",
 358               data_error.AsCString());
 359           return error;
 360         }
 361
 362         unsigned char buffer[16];
 363         ByteOrder byte_order = data.GetByteOrder();
 364
 365         data.CopyByteOrderedData(0, num_bytes, buffer, 16, byte_order);
 366         set_it_simple = true;
 367       } else {
 368         // FIXME - don't know how to do 80 bit long doubles yet.
 369         error.SetErrorString(
 370             "We don't support returning float values > 64 bits at present");
 371       }
 372     }
 373   }
 374
 375   if (!set_it_simple) {
 376     // Okay we've got a structure or something that doesn't fit in a simple
 377     // register. We should figure out where it really goes, but we don't
 378     // support this yet.
 379     error.SetErrorString("We only support setting simple integer and float "
 380                          "return types at present.");
 381   }
 382
 383   return error;
 384 }
 385
 386 //
 387 // ReturnValueExtractor
 388 //
 389
 390 namespace {
 391
 392 #define LOG_PREFIX "ReturnValueExtractor: "
 393
 394 class ReturnValueExtractor {
 395   // This class represents a register, from which data may be extracted.
 396   //
 397   // It may be constructed by directly specifying its index (where 0 is the
 398   // first register used to return values) or by specifying the offset of a
 399   // given struct field, in which case the appropriated register index will be
 400   // calculated.
 401   class Register {
 402   public:
 403     enum Type {
 404       GPR, // General Purpose Register
 405       FPR  // Floating Point Register
 406     };
 407
 408     // main constructor
 409     //
 410     // offs - field offset in struct
 411     Register(Type ty, uint32_t index, uint32_t offs, RegisterContext *reg_ctx,
 412              ByteOrder byte_order)
 413         : m_index(index), m_offs(offs % sizeof(uint64_t)),
 414           m_avail(sizeof(uint64_t) - m_offs), m_type(ty), m_reg_ctx(reg_ctx),
 415           m_byte_order(byte_order) {}
 416
 417     // explicit index, no offset
 418     Register(Type ty, uint32_t index, RegisterContext *reg_ctx,
 419              ByteOrder byte_order)
 420         : Register(ty, index, 0, reg_ctx, byte_order) {}
 421
 422     // GPR, calculate index from offs
 423     Register(uint32_t offs, RegisterContext *reg_ctx, ByteOrder byte_order)
 424         : Register(GPR, offs / sizeof(uint64_t), offs, reg_ctx, byte_order) {}
 425
 426     uint32_t Index() const { return m_index; }
 427
 428     // register offset where data is located
 429     uint32_t Offs() const { return m_offs; }
 430
 431     // available bytes in this register
 432     uint32_t Avail() const { return m_avail; }
 433
 434     bool IsValid() const {
 435       if (m_index > 7) {
 436         LLDB_LOG(m_log, LOG_PREFIX
 437                  "No more than 8 registers should be used to return values");
 438         return false;
 439       }
 440       return true;
 441     }
 442
 443     std::string GetName() const {
 444       if (m_type == GPR)
 445         return ("r" + llvm::Twine(m_index + 3)).str();
 446       else
 447         return ("f" + llvm::Twine(m_index + 1)).str();
 448     }
 449
 450     // get raw register data
 451     bool GetRawData(uint64_t &raw_data) {
 452       const RegisterInfo *reg_info =
 453           m_reg_ctx->GetRegisterInfoByName(GetName());
 454       if (!reg_info) {
 455         LLDB_LOG(m_log, LOG_PREFIX "Failed to get RegisterInfo");
 456         return false;
 457       }
 458
 459       RegisterValue reg_val;
 460       if (!m_reg_ctx->ReadRegister(reg_info, reg_val)) {
 461         LLDB_LOG(m_log, LOG_PREFIX "ReadRegister() failed");
 462         return false;
 463       }
 464
 465       Status error;
 466       uint32_t rc = reg_val.GetAsMemoryData(
 467           *reg_info, &raw_data, sizeof(raw_data), m_byte_order, error);
 468       if (rc != sizeof(raw_data)) {
 469         LLDB_LOG(m_log, LOG_PREFIX "GetAsMemoryData() failed");
 470         return false;
 471       }
 472
 473       return true;
 474     }
 475
 476   private:
 477     uint32_t m_index;
 478     uint32_t m_offs;
 479     uint32_t m_avail;
 480     Type m_type;
 481     RegisterContext *m_reg_ctx;
 482     ByteOrder m_byte_order;
 483     Log *m_log = GetLog(LLDBLog::Expressions);
 484   };
 485
 486   Register GetGPR(uint32_t index) const {
 487     return Register(Register::GPR, index, m_reg_ctx, m_byte_order);
 488   }
 489
 490   Register GetFPR(uint32_t index) const {
 491     return Register(Register::FPR, index, m_reg_ctx, m_byte_order);
 492   }
 493
 494   Register GetGPRByOffs(uint32_t offs) const {
 495     return Register(offs, m_reg_ctx, m_byte_order);
 496   }
 497
 498 public:
 499   // factory
 500   static llvm::Expected<ReturnValueExtractor> Create(Thread &thread,
 501                                                      CompilerType &type) {
 502     RegisterContext *reg_ctx = thread.GetRegisterContext().get();
 503     if (!reg_ctx)
 504       return llvm::make_error<llvm::StringError>(
 505           LOG_PREFIX "Failed to get RegisterContext",
 506           llvm::inconvertibleErrorCode());
 507
 508     ProcessSP process_sp = thread.GetProcess();
 509     if (!process_sp)
 510       return llvm::make_error<llvm::StringError>(
 511           LOG_PREFIX "GetProcess() failed", llvm::inconvertibleErrorCode());
 512
 513     return ReturnValueExtractor(thread, type, reg_ctx, process_sp);
 514   }
 515
 516   // main method: get value of the type specified at construction time
 517   ValueObjectSP GetValue() {
 518     const uint32_t type_flags = m_type.GetTypeInfo();
 519
 520     // call the appropriate type handler
 521     ValueSP value_sp;
 522     ValueObjectSP valobj_sp;
 523     if (type_flags & eTypeIsScalar) {
 524       if (type_flags & eTypeIsInteger) {
 525         value_sp = GetIntegerValue(0);
 526       } else if (type_flags & eTypeIsFloat) {
 527         if (type_flags & eTypeIsComplex) {
 528           LLDB_LOG(m_log, LOG_PREFIX "Complex numbers are not supported yet");
 529           return ValueObjectSP();
 530         } else {
 531           value_sp = GetFloatValue(m_type, 0);
 532         }
 533       }
 534     } else if (type_flags & eTypeIsPointer) {
 535       value_sp = GetPointerValue(0);
 536     }
 537
 538     if (value_sp) {
 539       valobj_sp = ValueObjectConstResult::Create(
 540           m_thread.GetStackFrameAtIndex(0).get(), *value_sp, ConstString(""));
 541     } else if (type_flags & eTypeIsVector) {
 542       valobj_sp = GetVectorValueObject();
 543     } else if (type_flags & eTypeIsStructUnion || type_flags & eTypeIsClass) {
 544       valobj_sp = GetStructValueObject();
 545     }
 546
 547     return valobj_sp;
 548   }
 549
 550 private:
 551   // data
 552   Thread &m_thread;
 553   CompilerType &m_type;
 554   uint64_t m_byte_size;
 555   std::unique_ptr<DataBufferHeap> m_data_up;
 556   int32_t m_src_offs = 0;
 557   int32_t m_dst_offs = 0;
 558   bool m_packed = false;
 559   Log *m_log = GetLog(LLDBLog::Expressions);
 560   RegisterContext *m_reg_ctx;
 561   ProcessSP m_process_sp;
 562   ByteOrder m_byte_order;
 563   uint32_t m_addr_size;
 564
 565   // methods
 566
 567   // constructor
 568   ReturnValueExtractor(Thread &thread, CompilerType &type,
 569                        RegisterContext *reg_ctx, ProcessSP process_sp)
 570       : m_thread(thread), m_type(type),
 571         m_byte_size(m_type.GetByteSize(&thread).value_or(0)),
 572         m_data_up(new DataBufferHeap(m_byte_size, 0)), m_reg_ctx(reg_ctx),
 573         m_process_sp(process_sp), m_byte_order(process_sp->GetByteOrder()),
 574         m_addr_size(
 575             process_sp->GetTarget().GetArchitecture().GetAddressByteSize()) {}
 576
 577   // build a new scalar value
 578   ValueSP NewScalarValue(CompilerType &type) {
 579     ValueSP value_sp(new Value);
 580     value_sp->SetCompilerType(type);
 581     value_sp->SetValueType(Value::ValueType::Scalar);
 582     return value_sp;
 583   }
 584
 585   // get an integer value in the specified register
 586   ValueSP GetIntegerValue(uint32_t reg_index) {
 587     uint64_t raw_value;
 588     auto reg = GetGPR(reg_index);
 589     if (!reg.GetRawData(raw_value))
 590       return ValueSP();
 591
 592     // build value from data
 593     ValueSP value_sp(NewScalarValue(m_type));
 594
 595     uint32_t type_flags = m_type.GetTypeInfo();
 596     bool is_signed = (type_flags & eTypeIsSigned) != 0;
 597
 598     switch (m_byte_size) {
 599     case sizeof(uint64_t):
 600       if (is_signed)
 601         value_sp->GetScalar() = (int64_t)(raw_value);
 602       else
 603         value_sp->GetScalar() = (uint64_t)(raw_value);
 604       break;
 605
 606     case sizeof(uint32_t):
 607       if (is_signed)
 608         value_sp->GetScalar() = (int32_t)(raw_value & UINT32_MAX);
 609       else
 610         value_sp->GetScalar() = (uint32_t)(raw_value & UINT32_MAX);
 611       break;
 612
 613     case sizeof(uint16_t):
 614       if (is_signed)
 615         value_sp->GetScalar() = (int16_t)(raw_value & UINT16_MAX);
 616       else
 617         value_sp->GetScalar() = (uint16_t)(raw_value & UINT16_MAX);
 618       break;
 619
 620     case sizeof(uint8_t):
 621       if (is_signed)
 622         value_sp->GetScalar() = (int8_t)(raw_value & UINT8_MAX);
 623       else
 624         value_sp->GetScalar() = (uint8_t)(raw_value & UINT8_MAX);
 625       break;
 626
 627     default:
 628       llvm_unreachable("Invalid integer size");
 629     }
 630
 631     return value_sp;
 632   }
 633
 634   // get a floating point value on the specified register
 635   ValueSP GetFloatValue(CompilerType &type, uint32_t reg_index) {
 636     uint64_t raw_data;
 637     auto reg = GetFPR(reg_index);
 638     if (!reg.GetRawData(raw_data))
 639       return {};
 640
 641     // build value from data
 642     ValueSP value_sp(NewScalarValue(type));
 643
 644     DataExtractor de(&raw_data, sizeof(raw_data), m_byte_order, m_addr_size);
 645
 646     offset_t offset = 0;
 647     std::optional<uint64_t> byte_size = type.GetByteSize(m_process_sp.get());
 648     if (!byte_size)
 649       return {};
 650     switch (*byte_size) {
 651     case sizeof(float):
 652       value_sp->GetScalar() = (float)de.GetDouble(&offset);
 653       break;
 654
 655     case sizeof(double):
 656       value_sp->GetScalar() = de.GetDouble(&offset);
 657       break;
 658
 659     default:
 660       llvm_unreachable("Invalid floating point size");
 661     }
 662
 663     return value_sp;
 664   }
 665
 666   // get pointer value from register
 667   ValueSP GetPointerValue(uint32_t reg_index) {
 668     uint64_t raw_data;
 669     auto reg = GetGPR(reg_index);
 670     if (!reg.GetRawData(raw_data))
 671       return ValueSP();
 672
 673     // build value from raw data
 674     ValueSP value_sp(NewScalarValue(m_type));
 675     value_sp->GetScalar() = raw_data;
 676     return value_sp;
 677   }
 678
 679   // build the ValueObject from our data buffer
 680   ValueObjectSP BuildValueObject() {
 681     DataExtractor de(DataBufferSP(m_data_up.release()), m_byte_order,
 682                      m_addr_size);
 683     return ValueObjectConstResult::Create(&m_thread, m_type, ConstString(""),
 684                                           de);
 685   }
 686
 687   // get a vector return value
 688   ValueObjectSP GetVectorValueObject() {
 689     const uint32_t MAX_VRS = 2;
 690
 691     // get first V register used to return values
 692     const RegisterInfo *vr[MAX_VRS];
 693     vr[0] = m_reg_ctx->GetRegisterInfoByName("vr2");
 694     if (!vr[0]) {
 695       LLDB_LOG(m_log, LOG_PREFIX "Failed to get vr2 RegisterInfo");
 696       return ValueObjectSP();
 697     }
 698
 699     const uint32_t vr_size = vr[0]->byte_size;
 700     size_t vrs = 1;
 701     if (m_byte_size > 2 * vr_size) {
 702       LLDB_LOG(
 703           m_log, LOG_PREFIX
 704           "Returning vectors that don't fit in 2 VR regs is not supported");
 705       return ValueObjectSP();
 706     }
 707
 708     // load vr3, if needed
 709     if (m_byte_size > vr_size) {
 710       vrs++;
 711       vr[1] = m_reg_ctx->GetRegisterInfoByName("vr3");
 712       if (!vr[1]) {
 713         LLDB_LOG(m_log, LOG_PREFIX "Failed to get vr3 RegisterInfo");
 714         return ValueObjectSP();
 715       }
 716     }
 717
 718     // Get the whole contents of vector registers and let the logic here
 719     // arrange the data properly.
 720
 721     RegisterValue vr_val[MAX_VRS];
 722     Status error;
 723     std::unique_ptr<DataBufferHeap> vr_data(
 724         new DataBufferHeap(vrs * vr_size, 0));
 725
 726     for (uint32_t i = 0; i < vrs; i++) {
 727       if (!m_reg_ctx->ReadRegister(vr[i], vr_val[i])) {
 728         LLDB_LOG(m_log, LOG_PREFIX "Failed to read vector register contents");
 729         return ValueObjectSP();
 730       }
 731       if (!vr_val[i].GetAsMemoryData(*vr[i], vr_data->GetBytes() + i * vr_size,
 732                                      vr_size, m_byte_order, error)) {
 733         LLDB_LOG(m_log, LOG_PREFIX "Failed to extract vector register bytes");
 734         return ValueObjectSP();
 735       }
 736     }
 737
 738     // The compiler generated code seems to always put the vector elements at
 739     // the end of the vector register, in case they don't occupy all of it.
 740     // This offset variable handles this.
 741     uint32_t offs = 0;
 742     if (m_byte_size < vr_size)
 743       offs = vr_size - m_byte_size;
 744
 745     // copy extracted data to our buffer
 746     memcpy(m_data_up->GetBytes(), vr_data->GetBytes() + offs, m_byte_size);
 747     return BuildValueObject();
 748   }
 749
 750   // get a struct return value
 751   ValueObjectSP GetStructValueObject() {
 752     // case 1: get from stack
 753     if (m_byte_size > 2 * sizeof(uint64_t)) {
 754       uint64_t addr;
 755       auto reg = GetGPR(0);
 756       if (!reg.GetRawData(addr))
 757         return {};
 758
 759       Status error;
 760       size_t rc = m_process_sp->ReadMemory(addr, m_data_up->GetBytes(),
 761                                            m_byte_size, error);
 762       if (rc != m_byte_size) {
 763         LLDB_LOG(m_log, LOG_PREFIX "Failed to read memory pointed by r3");
 764         return ValueObjectSP();
 765       }
 766       return BuildValueObject();
 767     }
 768
 769     // get number of children
 770     const bool omit_empty_base_classes = true;
 771     uint32_t n = m_type.GetNumChildren(omit_empty_base_classes, nullptr);
 772     if (!n) {
 773       LLDB_LOG(m_log, LOG_PREFIX "No children found in struct");
 774       return {};
 775     }
 776
 777     // case 2: homogeneous double or float aggregate
 778     CompilerType elem_type;
 779     if (m_type.IsHomogeneousAggregate(&elem_type)) {
 780       uint32_t type_flags = elem_type.GetTypeInfo();
 781       std::optional<uint64_t> elem_size =
 782           elem_type.GetByteSize(m_process_sp.get());
 783       if (!elem_size)
 784         return {};
 785       if (type_flags & eTypeIsComplex || !(type_flags & eTypeIsFloat)) {
 786         LLDB_LOG(m_log,
 787                  LOG_PREFIX "Unexpected type found in homogeneous aggregate");
 788         return {};
 789       }
 790
 791       for (uint32_t i = 0; i < n; i++) {
 792         ValueSP val_sp = GetFloatValue(elem_type, i);
 793         if (!val_sp)
 794           return {};
 795
 796         // copy to buffer
 797         Status error;
 798         size_t rc = val_sp->GetScalar().GetAsMemoryData(
 799             m_data_up->GetBytes() + m_dst_offs, *elem_size, m_byte_order,
 800             error);
 801         if (rc != *elem_size) {
 802           LLDB_LOG(m_log, LOG_PREFIX "Failed to get float data");
 803           return {};
 804         }
 805         m_dst_offs += *elem_size;
 806       }
 807       return BuildValueObject();
 808     }
 809
 810     // case 3: get from GPRs
 811
 812     // first, check if this is a packed struct or not
 813     auto ast = m_type.GetTypeSystem().dyn_cast_or_null<TypeSystemClang>();
 814     if (ast) {
 815       clang::RecordDecl *record_decl = TypeSystemClang::GetAsRecordDecl(m_type);
 816
 817       if (record_decl) {
 818         auto attrs = record_decl->attrs();
 819         for (const auto &attr : attrs) {
 820           if (attr->getKind() == clang::attr::Packed) {
 821             m_packed = true;
 822             break;
 823           }
 824         }
 825       }
 826     }
 827
 828     LLDB_LOG(m_log, LOG_PREFIX "{0} struct",
 829              m_packed ? "packed" : "not packed");
 830
 831     for (uint32_t i = 0; i < n; i++) {
 832       std::string name;
 833       uint32_t size;
 834       GetChildType(i, name, size);
 835       // NOTE: the offset returned by GetChildCompilerTypeAtIndex()
 836       //       can't be used because it never considers alignment bytes
 837       //       between struct fields.
 838       LLDB_LOG(m_log, LOG_PREFIX "field={0}, size={1}", name, size);
 839       if (!ExtractField(size))
 840         return ValueObjectSP();
 841     }
 842
 843     return BuildValueObject();
 844   }
 845
 846   // extract 'size' bytes at 'offs' from GPRs
 847   bool ExtractFromRegs(int32_t offs, uint32_t size, void *buf) {
 848     while (size) {
 849       auto reg = GetGPRByOffs(offs);
 850       if (!reg.IsValid())
 851         return false;
 852
 853       uint32_t n = std::min(reg.Avail(), size);
 854       uint64_t raw_data;
 855
 856       if (!reg.GetRawData(raw_data))
 857         return false;
 858
 859       memcpy(buf, (char *)&raw_data + reg.Offs(), n);
 860       offs += n;
 861       size -= n;
 862       buf = (char *)buf + n;
 863     }
 864     return true;
 865   }
 866
 867   // extract one field from GPRs and put it in our buffer
 868   bool ExtractField(uint32_t size) {
 869     auto reg = GetGPRByOffs(m_src_offs);
 870     if (!reg.IsValid())
 871       return false;
 872
 873     // handle padding
 874     if (!m_packed) {
 875       uint32_t n = m_src_offs % size;
 876
 877       // not 'size' bytes aligned
 878       if (n) {
 879         LLDB_LOG(m_log,
 880                  LOG_PREFIX "Extracting {0} alignment bytes at offset {1}", n,
 881                  m_src_offs);
 882         // get alignment bytes
 883         if (!ExtractFromRegs(m_src_offs, n, m_data_up->GetBytes() + m_dst_offs))
 884           return false;
 885         m_src_offs += n;
 886         m_dst_offs += n;
 887       }
 888     }
 889
 890     // get field
 891     LLDB_LOG(m_log, LOG_PREFIX "Extracting {0} field bytes at offset {1}", size,
 892              m_src_offs);
 893     if (!ExtractFromRegs(m_src_offs, size, m_data_up->GetBytes() + m_dst_offs))
 894       return false;
 895     m_src_offs += size;
 896     m_dst_offs += size;
 897     return true;
 898   }
 899
 900   // get child
 901   CompilerType GetChildType(uint32_t i, std::string &name, uint32_t &size) {
 902     // GetChild constant inputs
 903     const bool transparent_pointers = false;
 904     const bool omit_empty_base_classes = true;
 905     const bool ignore_array_bounds = false;
 906     // GetChild output params
 907     int32_t child_offs;
 908     uint32_t child_bitfield_bit_size;
 909     uint32_t child_bitfield_bit_offset;
 910     bool child_is_base_class;
 911     bool child_is_deref_of_parent;
 912     ValueObject *valobj = nullptr;
 913     uint64_t language_flags;
 914     ExecutionContext exe_ctx;
 915     m_thread.CalculateExecutionContext(exe_ctx);
 916
 917     return m_type.GetChildCompilerTypeAtIndex(
 918         &exe_ctx, i, transparent_pointers, omit_empty_base_classes,
 919         ignore_array_bounds, name, size, child_offs, child_bitfield_bit_size,
 920         child_bitfield_bit_offset, child_is_base_class,
 921         child_is_deref_of_parent, valobj, language_flags);
 922   }
 923 };
 924
 925 #undef LOG_PREFIX
 926
 927 } // anonymous namespace
 928
 929 ValueObjectSP
 930 ABISysV_ppc64::GetReturnValueObjectSimple(Thread &thread,
 931                                           CompilerType &type) const {
 932   if (!type)
 933     return ValueObjectSP();
 934
 935   auto exp_extractor = ReturnValueExtractor::Create(thread, type);
 936   if (!exp_extractor) {
 937     Log *log = GetLog(LLDBLog::Expressions);
 938     LLDB_LOG_ERROR(log, exp_extractor.takeError(),
 939                    "Extracting return value failed: {0}");
 940     return ValueObjectSP();
 941   }
 942
 943   return exp_extractor.get().GetValue();
 944 }
 945
 946 ValueObjectSP ABISysV_ppc64::GetReturnValueObjectImpl(
 947     Thread &thread, CompilerType &return_compiler_type) const {
 948   return GetReturnValueObjectSimple(thread, return_compiler_type);
 949 }
 950
 951 bool ABISysV_ppc64::CreateFunctionEntryUnwindPlan(UnwindPlan &unwind_plan) {
 952   unwind_plan.Clear();
 953   unwind_plan.SetRegisterKind(eRegisterKindDWARF);
 954
 955   uint32_t lr_reg_num;
 956   uint32_t sp_reg_num;
 957   uint32_t pc_reg_num;
 958
 959   if (GetByteOrder() == lldb::eByteOrderLittle) {
 960     lr_reg_num = ppc64le_dwarf::dwarf_lr_ppc64le;
 961     sp_reg_num = ppc64le_dwarf::dwarf_r1_ppc64le;
 962     pc_reg_num = ppc64le_dwarf::dwarf_pc_ppc64le;
 963   } else {
 964     lr_reg_num = ppc64_dwarf::dwarf_lr_ppc64;
 965     sp_reg_num = ppc64_dwarf::dwarf_r1_ppc64;
 966     pc_reg_num = ppc64_dwarf::dwarf_pc_ppc64;
 967   }
 968
 969   UnwindPlan::RowSP row(new UnwindPlan::Row);
 970
 971   // Our Call Frame Address is the stack pointer value
 972   row->GetCFAValue().SetIsRegisterPlusOffset(sp_reg_num, 0);
 973
 974   // The previous PC is in the LR
 975   row->SetRegisterLocationToRegister(pc_reg_num, lr_reg_num, true);
 976   unwind_plan.AppendRow(row);
 977
 978   // All other registers are the same.
 979
 980   unwind_plan.SetSourceName("ppc64 at-func-entry default");
 981   unwind_plan.SetSourcedFromCompiler(eLazyBoolNo);
 982
 983   return true;
 984 }
 985
 986 bool ABISysV_ppc64::CreateDefaultUnwindPlan(UnwindPlan &unwind_plan) {
 987   unwind_plan.Clear();
 988   unwind_plan.SetRegisterKind(eRegisterKindDWARF);
 989
 990   uint32_t sp_reg_num;
 991   uint32_t pc_reg_num;
 992   uint32_t cr_reg_num;
 993
 994   if (GetByteOrder() == lldb::eByteOrderLittle) {
 995     sp_reg_num = ppc64le_dwarf::dwarf_r1_ppc64le;
 996     pc_reg_num = ppc64le_dwarf::dwarf_lr_ppc64le;
 997     cr_reg_num = ppc64le_dwarf::dwarf_cr_ppc64le;
 998   } else {
 999     sp_reg_num = ppc64_dwarf::dwarf_r1_ppc64;
1000     pc_reg_num = ppc64_dwarf::dwarf_lr_ppc64;
1001     cr_reg_num = ppc64_dwarf::dwarf_cr_ppc64;
1002   }
1003
1004   UnwindPlan::RowSP row(new UnwindPlan::Row);
1005   const int32_t ptr_size = 8;
1006   row->SetUnspecifiedRegistersAreUndefined(true);
1007   row->GetCFAValue().SetIsRegisterDereferenced(sp_reg_num);
1008
1009   row->SetRegisterLocationToAtCFAPlusOffset(pc_reg_num, ptr_size * 2, true);
1010   row->SetRegisterLocationToIsCFAPlusOffset(sp_reg_num, 0, true);
1011   row->SetRegisterLocationToAtCFAPlusOffset(cr_reg_num, ptr_size, true);
1012
1013   unwind_plan.AppendRow(row);
1014   unwind_plan.SetSourceName("ppc64 default unwind plan");
1015   unwind_plan.SetSourcedFromCompiler(eLazyBoolNo);
1016   unwind_plan.SetUnwindPlanValidAtAllInstructions(eLazyBoolNo);
1017   unwind_plan.SetUnwindPlanForSignalTrap(eLazyBoolNo);
1018   unwind_plan.SetReturnAddressRegister(pc_reg_num);
1019   return true;
1020 }
1021
1022 bool ABISysV_ppc64::RegisterIsVolatile(const RegisterInfo *reg_info) {
1023   return !RegisterIsCalleeSaved(reg_info);
1024 }
1025
1026 // See "Register Usage" in the
1027 // "System V Application Binary Interface"
1028 // "64-bit PowerPC ELF Application Binary Interface Supplement" current version
1029 // is 2 released 2015 at
1030 // https://members.openpowerfoundation.org/document/dl/576
1031 bool ABISysV_ppc64::RegisterIsCalleeSaved(const RegisterInfo *reg_info) {
1032   if (reg_info) {
1033     // Preserved registers are :
1034     //    r1,r2,r13-r31
1035     //    cr2-cr4 (partially preserved)
1036     //    f14-f31 (not yet)
1037     //    v20-v31 (not yet)
1038     //    vrsave (not yet)
1039
1040     const char *name = reg_info->name;
1041     if (name[0] == 'r') {
1042       if ((name[1] == '1' || name[1] == '2') && name[2] == '\0')
1043         return true;
1044       if (name[1] == '1' && name[2] > '2')
1045         return true;
1046       if ((name[1] == '2' || name[1] == '3') && name[2] != '\0')
1047         return true;
1048     }
1049
1050     if (name[0] == 'f' && name[1] >= '0' && name[2] <= '9') {
1051       if (name[2] == '\0')
1052         return false;
1053       if (name[1] == '1' && name[2] >= '4')
1054         return true;
1055       if ((name[1] == '2' || name[1] == '3') && name[2] != '\0')
1056         return true;
1057     }
1058
1059     if (name[0] == 's' && name[1] == 'p' && name[2] == '\0') // sp
1060       return true;
1061     if (name[0] == 'f' && name[1] == 'p' && name[2] == '\0') // fp
1062       return false;
1063     if (name[0] == 'p' && name[1] == 'c' && name[2] == '\0') // pc
1064       return true;
1065   }
1066   return false;
1067 }
1068
1069 void ABISysV_ppc64::Initialize() {
1070   PluginManager::RegisterPlugin(
1071       GetPluginNameStatic(), "System V ABI for ppc64 targets", CreateInstance);
1072 }
1073
1074 void ABISysV_ppc64::Terminate() {
1075   PluginManager::UnregisterPlugin(CreateInstance);
1076 }