source/Plugins/ABI/SysV-ppc/ABISysV_ppc.cpp

   1 //===-- ABISysV_ppc.cpp -----------------------------------------*- C++ -*-===//
   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 #include "ABISysV_ppc.h"
  11
  12 // C Includes
  13 // C++ Includes
  14 // Other libraries and framework includes
  15 #include "llvm/ADT/STLExtras.h"
  16 #include "llvm/ADT/Triple.h"
  17
  18 // Project includes
  19 #include "lldb/Core/ConstString.h"
  20 #include "lldb/Core/DataExtractor.h"
  21 #include "lldb/Core/Error.h"
  22 #include "lldb/Core/Log.h"
  23 #include "lldb/Core/Module.h"
  24 #include "lldb/Core/PluginManager.h"
  25 #include "lldb/Core/RegisterValue.h"
  26 #include "lldb/Core/Value.h"
  27 #include "lldb/Core/ValueObjectConstResult.h"
  28 #include "lldb/Core/ValueObjectRegister.h"
  29 #include "lldb/Core/ValueObjectMemory.h"
  30 #include "lldb/Symbol/UnwindPlan.h"
  31 #include "lldb/Target/Target.h"
  32 #include "lldb/Target/Process.h"
  33 #include "lldb/Target/RegisterContext.h"
  34 #include "lldb/Target/StackFrame.h"
  35 #include "lldb/Target/Thread.h"
  36
  37 using namespace lldb;
  38 using namespace lldb_private;
  39
  40 enum dwarf_regnums
  41 {
  42     dwarf_r0 = 0,
  43     dwarf_r1,
  44     dwarf_r2,
  45     dwarf_r3,
  46     dwarf_r4,
  47     dwarf_r5,
  48     dwarf_r6,
  49     dwarf_r7,
  50     dwarf_r8,
  51     dwarf_r9,
  52     dwarf_r10,
  53     dwarf_r11,
  54     dwarf_r12,
  55     dwarf_r13,
  56     dwarf_r14,
  57     dwarf_r15,
  58     dwarf_r16,
  59     dwarf_r17,
  60     dwarf_r18,
  61     dwarf_r19,
  62     dwarf_r20,
  63     dwarf_r21,
  64     dwarf_r22,
  65     dwarf_r23,
  66     dwarf_r24,
  67     dwarf_r25,
  68     dwarf_r26,
  69     dwarf_r27,
  70     dwarf_r28,
  71     dwarf_r29,
  72     dwarf_r30,
  73     dwarf_r31,
  74     dwarf_f0,
  75     dwarf_f1,
  76     dwarf_f2,
  77     dwarf_f3,
  78     dwarf_f4,
  79     dwarf_f5,
  80     dwarf_f6,
  81     dwarf_f7,
  82     dwarf_f8,
  83     dwarf_f9,
  84     dwarf_f10,
  85     dwarf_f11,
  86     dwarf_f12,
  87     dwarf_f13,
  88     dwarf_f14,
  89     dwarf_f15,
  90     dwarf_f16,
  91     dwarf_f17,
  92     dwarf_f18,
  93     dwarf_f19,
  94     dwarf_f20,
  95     dwarf_f21,
  96     dwarf_f22,
  97     dwarf_f23,
  98     dwarf_f24,
  99     dwarf_f25,
 100     dwarf_f26,
 101     dwarf_f27,
 102     dwarf_f28,
 103     dwarf_f29,
 104     dwarf_f30,
 105     dwarf_f31,
 106     dwarf_cr,
 107     dwarf_fpscr,
 108     dwarf_xer = 101,
 109     dwarf_lr = 108,
 110     dwarf_ctr,
 111     dwarf_pc,
 112     dwarf_cfa,
 113 };
 114
 115 // Note that the size and offset will be updated by platform-specific classes.
 116 #define DEFINE_GPR(reg, alt, kind1, kind2, kind3, kind4)           \
 117     { #reg, alt, 8, 0, eEncodingUint, \
 118       eFormatHex, { kind1, kind2, kind3, kind4}, nullptr, nullptr }
 119
 120 static const RegisterInfo
 121 g_register_infos[] =
 122 {
 123     // General purpose registers.             eh_frame,                 DWARF,              Generic,    Process Plugin
 124     DEFINE_GPR(r0,       nullptr, dwarf_r0,    dwarf_r0,    LLDB_INVALID_REGNUM,    LLDB_INVALID_REGNUM),
 125     DEFINE_GPR(r1,       "sp",    dwarf_r1,    dwarf_r1,    LLDB_REGNUM_GENERIC_SP, LLDB_INVALID_REGNUM),
 126     DEFINE_GPR(r2,       nullptr, dwarf_r2,    dwarf_r2,    LLDB_INVALID_REGNUM,    LLDB_INVALID_REGNUM),
 127     DEFINE_GPR(r3,       "arg1",  dwarf_r3,    dwarf_r3,    LLDB_REGNUM_GENERIC_ARG1, LLDB_INVALID_REGNUM),
 128     DEFINE_GPR(r4,       "arg2",  dwarf_r4,    dwarf_r4,    LLDB_REGNUM_GENERIC_ARG2 ,LLDB_INVALID_REGNUM),
 129     DEFINE_GPR(r5,       "arg3",  dwarf_r5,    dwarf_r5,    LLDB_REGNUM_GENERIC_ARG3, LLDB_INVALID_REGNUM),
 130     DEFINE_GPR(r6,       "arg4",  dwarf_r6,    dwarf_r6,    LLDB_REGNUM_GENERIC_ARG4, LLDB_INVALID_REGNUM),
 131     DEFINE_GPR(r7,       "arg5",  dwarf_r7,    dwarf_r7,    LLDB_REGNUM_GENERIC_ARG5, LLDB_INVALID_REGNUM),
 132     DEFINE_GPR(r8,       "arg6",  dwarf_r8,    dwarf_r8,    LLDB_REGNUM_GENERIC_ARG6, LLDB_INVALID_REGNUM),
 133     DEFINE_GPR(r9,       "arg7",  dwarf_r9,    dwarf_r9,    LLDB_REGNUM_GENERIC_ARG7, LLDB_INVALID_REGNUM),
 134     DEFINE_GPR(r10,      "arg8",  dwarf_r10,   dwarf_r10,   LLDB_REGNUM_GENERIC_ARG8, LLDB_INVALID_REGNUM),
 135     DEFINE_GPR(r11,      nullptr, dwarf_r11,   dwarf_r11,   LLDB_INVALID_REGNUM,    LLDB_INVALID_REGNUM),
 136     DEFINE_GPR(r12,      nullptr, dwarf_r12,   dwarf_r12,   LLDB_INVALID_REGNUM,    LLDB_INVALID_REGNUM),
 137     DEFINE_GPR(r13,      nullptr, dwarf_r13,   dwarf_r13,   LLDB_INVALID_REGNUM,    LLDB_INVALID_REGNUM),
 138     DEFINE_GPR(r14,      nullptr, dwarf_r14,   dwarf_r14,   LLDB_INVALID_REGNUM,    LLDB_INVALID_REGNUM),
 139     DEFINE_GPR(r15,      nullptr, dwarf_r15,   dwarf_r15,   LLDB_INVALID_REGNUM,    LLDB_INVALID_REGNUM),
 140     DEFINE_GPR(r16,      nullptr, dwarf_r16,   dwarf_r16,   LLDB_INVALID_REGNUM,    LLDB_INVALID_REGNUM),
 141     DEFINE_GPR(r17,      nullptr, dwarf_r17,   dwarf_r17,   LLDB_INVALID_REGNUM,    LLDB_INVALID_REGNUM),
 142     DEFINE_GPR(r18,      nullptr, dwarf_r18,   dwarf_r18,   LLDB_INVALID_REGNUM,    LLDB_INVALID_REGNUM),
 143     DEFINE_GPR(r19,      nullptr, dwarf_r19,   dwarf_r19,   LLDB_INVALID_REGNUM,    LLDB_INVALID_REGNUM),
 144     DEFINE_GPR(r20,      nullptr, dwarf_r20,   dwarf_r20,   LLDB_INVALID_REGNUM,    LLDB_INVALID_REGNUM),
 145     DEFINE_GPR(r21,      nullptr, dwarf_r21,   dwarf_r21,   LLDB_INVALID_REGNUM,    LLDB_INVALID_REGNUM),
 146     DEFINE_GPR(r22,      nullptr, dwarf_r22,   dwarf_r22,   LLDB_INVALID_REGNUM,    LLDB_INVALID_REGNUM),
 147     DEFINE_GPR(r23,      nullptr, dwarf_r23,   dwarf_r23,   LLDB_INVALID_REGNUM,    LLDB_INVALID_REGNUM),
 148     DEFINE_GPR(r24,      nullptr, dwarf_r24,   dwarf_r24,   LLDB_INVALID_REGNUM,    LLDB_INVALID_REGNUM),
 149     DEFINE_GPR(r25,      nullptr, dwarf_r25,   dwarf_r25,   LLDB_INVALID_REGNUM,    LLDB_INVALID_REGNUM),
 150     DEFINE_GPR(r26,      nullptr, dwarf_r26,   dwarf_r26,   LLDB_INVALID_REGNUM,    LLDB_INVALID_REGNUM),
 151     DEFINE_GPR(r27,      nullptr, dwarf_r27,   dwarf_r27,   LLDB_INVALID_REGNUM,    LLDB_INVALID_REGNUM),
 152     DEFINE_GPR(r28,      nullptr, dwarf_r28,   dwarf_r28,   LLDB_INVALID_REGNUM,    LLDB_INVALID_REGNUM),
 153     DEFINE_GPR(r29,      nullptr, dwarf_r29,   dwarf_r29,   LLDB_INVALID_REGNUM,    LLDB_INVALID_REGNUM),
 154     DEFINE_GPR(r30,      nullptr, dwarf_r30,   dwarf_r30,   LLDB_INVALID_REGNUM,    LLDB_INVALID_REGNUM),
 155     DEFINE_GPR(r31,      nullptr, dwarf_r31,   dwarf_r31,   LLDB_INVALID_REGNUM,    LLDB_INVALID_REGNUM),
 156     DEFINE_GPR(lr,       "lr",    dwarf_lr,    dwarf_lr,    LLDB_REGNUM_GENERIC_RA, LLDB_INVALID_REGNUM),
 157     DEFINE_GPR(cr,       "cr",    dwarf_cr,    dwarf_cr,    LLDB_REGNUM_GENERIC_FLAGS, LLDB_INVALID_REGNUM),
 158     DEFINE_GPR(xer,      "xer",   dwarf_xer,   dwarf_xer,   LLDB_INVALID_REGNUM,    LLDB_INVALID_REGNUM),
 159     DEFINE_GPR(ctr,      "ctr",   dwarf_ctr,   dwarf_ctr,   LLDB_INVALID_REGNUM,    LLDB_INVALID_REGNUM),
 160     DEFINE_GPR(pc,       "pc",    dwarf_pc,    dwarf_pc,    LLDB_REGNUM_GENERIC_PC, LLDB_INVALID_REGNUM),
 161     { nullptr, nullptr, 8, 0, eEncodingUint, eFormatHex, { dwarf_cfa, dwarf_cfa, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr }
 162 };
 163
 164 static const uint32_t k_num_register_infos = llvm::array_lengthof(g_register_infos);
 165
 166 const lldb_private::RegisterInfo *
 167 ABISysV_ppc::GetRegisterInfoArray (uint32_t &count)
 168 {
 169     count = k_num_register_infos;
 170     return g_register_infos;
 171 }
 172
 173 size_t
 174 ABISysV_ppc::GetRedZoneSize () const
 175 {
 176     return 224;
 177 }
 178
 179 //------------------------------------------------------------------
 180 // Static Functions
 181 //------------------------------------------------------------------
 182
 183 ABISP
 184 ABISysV_ppc::CreateInstance (const ArchSpec &arch)
 185 {
 186     static ABISP g_abi_sp;
 187     if (arch.GetTriple().getArch() == llvm::Triple::ppc)
 188     {
 189         if (!g_abi_sp)
 190             g_abi_sp.reset (new ABISysV_ppc);
 191         return g_abi_sp;
 192     }
 193     return ABISP();
 194 }
 195
 196 bool
 197 ABISysV_ppc::PrepareTrivialCall (Thread &thread,
 198                                     addr_t sp,
 199                                     addr_t func_addr,
 200                                     addr_t return_addr,
 201                                     llvm::ArrayRef<addr_t> args) const
 202 {
 203     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));
 204
 205     if (log)
 206     {
 207         StreamString s;
 208         s.Printf("ABISysV_ppc::PrepareTrivialCall (tid = 0x%" PRIx64 ", sp = 0x%" PRIx64 ", func_addr = 0x%" PRIx64 ", return_addr = 0x%" PRIx64,
 209                     thread.GetID(),
 210                     (uint64_t)sp,
 211                     (uint64_t)func_addr,
 212                     (uint64_t)return_addr);
 213
 214         for (size_t i = 0; i < args.size(); ++i)
 215             s.Printf (", arg%" PRIu64 " = 0x%" PRIx64, static_cast<uint64_t>(i + 1), args[i]);
 216         s.PutCString (")");
 217         log->PutCString(s.GetString().c_str());
 218     }
 219
 220     RegisterContext *reg_ctx = thread.GetRegisterContext().get();
 221     if (!reg_ctx)
 222         return false;
 223
 224     const RegisterInfo *reg_info = nullptr;
 225
 226     if (args.size() > 8) // TODO handle more than 8 arguments
 227         return false;
 228
 229     for (size_t i = 0; i < args.size(); ++i)
 230     {
 231         reg_info = reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG1 + i);
 232         if (log)
 233             log->Printf("About to write arg%" PRIu64 " (0x%" PRIx64 ") into %s", static_cast<uint64_t>(i + 1), args[i], reg_info->name);
 234         if (!reg_ctx->WriteRegisterFromUnsigned(reg_info, args[i]))
 235             return false;
 236     }
 237
 238     // First, align the SP
 239
 240     if (log)
 241         log->Printf("16-byte aligning SP: 0x%" PRIx64 " to 0x%" PRIx64, (uint64_t)sp, (uint64_t)(sp & ~0xfull));
 242
 243     sp &= ~(0xfull); // 16-byte alignment
 244
 245     sp -= 8;
 246
 247     Error error;
 248     const RegisterInfo *pc_reg_info = reg_ctx->GetRegisterInfo (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC);
 249     const RegisterInfo *sp_reg_info = reg_ctx->GetRegisterInfo (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP);
 250     ProcessSP process_sp (thread.GetProcess());
 251
 252     RegisterValue reg_value;
 253
 254 #if 0
 255     // This code adds an extra frame so that we don't lose the function that we came from
 256     // by pushing the PC and the FP and then writing the current FP to point to the FP value
 257     // we just pushed. It is disabled for now until the stack backtracing code can be debugged.
 258
 259     // Save current PC
 260     const RegisterInfo *fp_reg_info = reg_ctx->GetRegisterInfo (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_FP);
 261     if (reg_ctx->ReadRegister(pc_reg_info, reg_value))
 262     {
 263         if (log)
 264             log->Printf("Pushing the current PC onto the stack: 0x%" PRIx64 ": 0x%" PRIx64, (uint64_t)sp, reg_value.GetAsUInt64());
 265
 266         if (!process_sp->WritePointerToMemory(sp, reg_value.GetAsUInt64(), error))
 267             return false;
 268
 269         sp -= 8;
 270
 271         // Save current FP
 272         if (reg_ctx->ReadRegister(fp_reg_info, reg_value))
 273         {
 274             if (log)
 275                 log->Printf("Pushing the current FP onto the stack: 0x%" PRIx64 ": 0x%" PRIx64, (uint64_t)sp, reg_value.GetAsUInt64());
 276
 277             if (!process_sp->WritePointerToMemory(sp, reg_value.GetAsUInt64(), error))
 278                 return false;
 279         }
 280         // Setup FP backchain
 281         reg_value.SetUInt64 (sp);
 282
 283         if (log)
 284             log->Printf("Writing FP:  0x%" PRIx64 " (for FP backchain)", reg_value.GetAsUInt64());
 285
 286         if (!reg_ctx->WriteRegister(fp_reg_info, reg_value))
 287         {
 288             return false;
 289         }
 290
 291         sp -= 8;
 292     }
 293 #endif
 294
 295     if (log)
 296         log->Printf("Pushing the return address onto the stack: 0x%" PRIx64 ": 0x%" PRIx64, (uint64_t)sp, (uint64_t)return_addr);
 297
 298     // Save return address onto the stack
 299     if (!process_sp->WritePointerToMemory(sp, return_addr, error))
 300         return false;
 301
 302     // %r1 is set to the actual stack value.
 303
 304     if (log)
 305         log->Printf("Writing SP: 0x%" PRIx64, (uint64_t)sp);
 306
 307     if (!reg_ctx->WriteRegisterFromUnsigned (sp_reg_info, sp))
 308         return false;
 309
 310     // %pc is set to the address of the called function.
 311
 312     if (log)
 313         log->Printf("Writing IP: 0x%" PRIx64, (uint64_t)func_addr);
 314
 315     if (!reg_ctx->WriteRegisterFromUnsigned (pc_reg_info, func_addr))
 316         return false;
 317
 318     return true;
 319 }
 320
 321 static bool ReadIntegerArgument(Scalar           &scalar,
 322                                 unsigned int     bit_width,
 323                                 bool             is_signed,
 324                                 Thread           &thread,
 325                                 uint32_t         *argument_register_ids,
 326                                 unsigned int     &current_argument_register,
 327                                 addr_t           &current_stack_argument)
 328 {
 329     if (bit_width > 64)
 330         return false; // Scalar can't hold large integer arguments
 331
 332     if (current_argument_register < 6)
 333     {
 334         scalar = thread.GetRegisterContext()->ReadRegisterAsUnsigned(argument_register_ids[current_argument_register], 0);
 335         current_argument_register++;
 336         if (is_signed)
 337             scalar.SignExtend (bit_width);
 338     }
 339     else
 340     {
 341         uint32_t byte_size = (bit_width + (8-1))/8;
 342         Error error;
 343         if (thread.GetProcess()->ReadScalarIntegerFromMemory(current_stack_argument, byte_size, is_signed, scalar, error))
 344         {
 345             current_stack_argument += byte_size;
 346             return true;
 347         }
 348         return false;
 349     }
 350     return true;
 351 }
 352
 353 bool
 354 ABISysV_ppc::GetArgumentValues (Thread &thread,
 355                                 ValueList &values) const
 356 {
 357     unsigned int num_values = values.GetSize();
 358     unsigned int value_index;
 359
 360     // Extract the register context so we can read arguments from registers
 361
 362     RegisterContext *reg_ctx = thread.GetRegisterContext().get();
 363
 364     if (!reg_ctx)
 365         return false;
 366
 367     // Get the pointer to the first stack argument so we have a place to start
 368     // when reading data
 369
 370     addr_t sp = reg_ctx->GetSP(0);
 371
 372     if (!sp)
 373         return false;
 374
 375     addr_t current_stack_argument = sp + 48; // jump over return address
 376
 377     uint32_t argument_register_ids[8];
 378
 379     argument_register_ids[0] = reg_ctx->GetRegisterInfo (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG1)->kinds[eRegisterKindLLDB];
 380     argument_register_ids[1] = reg_ctx->GetRegisterInfo (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG2)->kinds[eRegisterKindLLDB];
 381     argument_register_ids[2] = reg_ctx->GetRegisterInfo (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG3)->kinds[eRegisterKindLLDB];
 382     argument_register_ids[3] = reg_ctx->GetRegisterInfo (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG4)->kinds[eRegisterKindLLDB];
 383     argument_register_ids[4] = reg_ctx->GetRegisterInfo (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG5)->kinds[eRegisterKindLLDB];
 384     argument_register_ids[5] = reg_ctx->GetRegisterInfo (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG6)->kinds[eRegisterKindLLDB];
 385     argument_register_ids[6] = reg_ctx->GetRegisterInfo (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG7)->kinds[eRegisterKindLLDB];
 386     argument_register_ids[7] = reg_ctx->GetRegisterInfo (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG8)->kinds[eRegisterKindLLDB];
 387
 388     unsigned int current_argument_register = 0;
 389
 390     for (value_index = 0;
 391          value_index < num_values;
 392          ++value_index)
 393     {
 394         Value *value = values.GetValueAtIndex(value_index);
 395
 396         if (!value)
 397             return false;
 398
 399         // We currently only support extracting values with Clang QualTypes.
 400         // Do we care about others?
 401         CompilerType compiler_type = value->GetCompilerType();
 402         if (!compiler_type)
 403             return false;
 404         bool is_signed;
 405
 406         if (compiler_type.IsIntegerOrEnumerationType (is_signed))
 407         {
 408             ReadIntegerArgument(value->GetScalar(),
 409                                 compiler_type.GetBitSize(&thread),
 410                                 is_signed,
 411                                 thread,
 412                                 argument_register_ids,
 413                                 current_argument_register,
 414                                 current_stack_argument);
 415         }
 416         else if (compiler_type.IsPointerType ())
 417         {
 418             ReadIntegerArgument(value->GetScalar(),
 419                                 compiler_type.GetBitSize(&thread),
 420                                 false,
 421                                 thread,
 422                                 argument_register_ids,
 423                                 current_argument_register,
 424                                 current_stack_argument);
 425         }
 426     }
 427
 428     return true;
 429 }
 430
 431 Error
 432 ABISysV_ppc::SetReturnValueObject(lldb::StackFrameSP &frame_sp, lldb::ValueObjectSP &new_value_sp)
 433 {
 434     Error error;
 435     if (!new_value_sp)
 436     {
 437         error.SetErrorString("Empty value object for return value.");
 438         return error;
 439     }
 440
 441     CompilerType compiler_type = new_value_sp->GetCompilerType();
 442     if (!compiler_type)
 443     {
 444         error.SetErrorString ("Null clang type for return value.");
 445         return error;
 446     }
 447
 448     Thread *thread = frame_sp->GetThread().get();
 449
 450     bool is_signed;
 451     uint32_t count;
 452     bool is_complex;
 453
 454     RegisterContext *reg_ctx = thread->GetRegisterContext().get();
 455
 456     bool set_it_simple = false;
 457     if (compiler_type.IsIntegerOrEnumerationType (is_signed) || compiler_type.IsPointerType())
 458     {
 459         const RegisterInfo *reg_info = reg_ctx->GetRegisterInfoByName("r3", 0);
 460
 461         DataExtractor data;
 462         Error data_error;
 463         size_t num_bytes = new_value_sp->GetData(data, data_error);
 464         if (data_error.Fail())
 465         {
 466             error.SetErrorStringWithFormat("Couldn't convert return value to raw data: %s", data_error.AsCString());
 467             return error;
 468         }
 469         lldb::offset_t offset = 0;
 470         if (num_bytes <= 8)
 471         {
 472             uint64_t raw_value = data.GetMaxU64(&offset, num_bytes);
 473
 474             if (reg_ctx->WriteRegisterFromUnsigned (reg_info, raw_value))
 475                 set_it_simple = true;
 476         }
 477         else
 478         {
 479             error.SetErrorString("We don't support returning longer than 64 bit integer values at present.");
 480         }
 481     }
 482     else if (compiler_type.IsFloatingPointType (count, is_complex))
 483     {
 484         if (is_complex)
 485             error.SetErrorString ("We don't support returning complex values at present");
 486         else
 487         {
 488             size_t bit_width = compiler_type.GetBitSize(frame_sp.get());
 489             if (bit_width <= 64)
 490             {
 491                 DataExtractor data;
 492                 Error data_error;
 493                 size_t num_bytes = new_value_sp->GetData(data, data_error);
 494                 if (data_error.Fail())
 495                 {
 496                     error.SetErrorStringWithFormat("Couldn't convert return value to raw data: %s", data_error.AsCString());
 497                     return error;
 498                 }
 499
 500                 unsigned char buffer[16];
 501                 ByteOrder byte_order = data.GetByteOrder();
 502
 503                 data.CopyByteOrderedData (0, num_bytes, buffer, 16, byte_order);
 504                 set_it_simple = true;
 505             }
 506             else
 507             {
 508                 // FIXME - don't know how to do 80 bit long doubles yet.
 509                 error.SetErrorString ("We don't support returning float values > 64 bits at present");
 510             }
 511         }
 512     }
 513
 514     if (!set_it_simple)
 515     {
 516         // Okay we've got a structure or something that doesn't fit in a simple register.
 517         // We should figure out where it really goes, but we don't support this yet.
 518         error.SetErrorString ("We only support setting simple integer and float return types at present.");
 519     }
 520
 521     return error;
 522 }
 523
 524 ValueObjectSP
 525 ABISysV_ppc::GetReturnValueObjectSimple (Thread &thread,
 526                                          CompilerType &return_compiler_type) const
 527 {
 528     ValueObjectSP return_valobj_sp;
 529     Value value;
 530
 531     if (!return_compiler_type)
 532         return return_valobj_sp;
 533
 534     //value.SetContext (Value::eContextTypeClangType, return_value_type);
 535     value.SetCompilerType (return_compiler_type);
 536
 537     RegisterContext *reg_ctx = thread.GetRegisterContext().get();
 538     if (!reg_ctx)
 539         return return_valobj_sp;
 540
 541     const uint32_t type_flags = return_compiler_type.GetTypeInfo ();
 542     if (type_flags & eTypeIsScalar)
 543     {
 544         value.SetValueType(Value::eValueTypeScalar);
 545
 546         bool success = false;
 547         if (type_flags & eTypeIsInteger)
 548         {
 549             // Extract the register context so we can read arguments from registers
 550
 551             const size_t byte_size = return_compiler_type.GetByteSize(nullptr);
 552             uint64_t raw_value = thread.GetRegisterContext()->ReadRegisterAsUnsigned(reg_ctx->GetRegisterInfoByName("r3", 0), 0);
 553             const bool is_signed = (type_flags & eTypeIsSigned) != 0;
 554             switch (byte_size)
 555             {
 556             default:
 557                 break;
 558
 559             case sizeof(uint64_t):
 560                 if (is_signed)
 561                     value.GetScalar() = (int64_t)(raw_value);
 562                 else
 563                     value.GetScalar() = (uint64_t)(raw_value);
 564                 success = true;
 565                 break;
 566
 567             case sizeof(uint32_t):
 568                 if (is_signed)
 569                     value.GetScalar() = (int32_t)(raw_value & UINT32_MAX);
 570                 else
 571                     value.GetScalar() = (uint32_t)(raw_value & UINT32_MAX);
 572                 success = true;
 573                 break;
 574
 575             case sizeof(uint16_t):
 576                 if (is_signed)
 577                     value.GetScalar() = (int16_t)(raw_value & UINT16_MAX);
 578                 else
 579                     value.GetScalar() = (uint16_t)(raw_value & UINT16_MAX);
 580                 success = true;
 581                 break;
 582
 583             case sizeof(uint8_t):
 584                 if (is_signed)
 585                     value.GetScalar() = (int8_t)(raw_value & UINT8_MAX);
 586                 else
 587                     value.GetScalar() = (uint8_t)(raw_value & UINT8_MAX);
 588                 success = true;
 589                 break;
 590             }
 591         }
 592         else if (type_flags & eTypeIsFloat)
 593         {
 594             if (type_flags & eTypeIsComplex)
 595             {
 596                 // Don't handle complex yet.
 597             }
 598             else
 599             {
 600                 const size_t byte_size = return_compiler_type.GetByteSize(nullptr);
 601                 if (byte_size <= sizeof(long double))
 602                 {
 603                     const RegisterInfo *f1_info = reg_ctx->GetRegisterInfoByName("f1", 0);
 604                     RegisterValue f1_value;
 605                     if (reg_ctx->ReadRegister (f1_info, f1_value))
 606                     {
 607                         DataExtractor data;
 608                         if (f1_value.GetData(data))
 609                         {
 610                             lldb::offset_t offset = 0;
 611                             if (byte_size == sizeof(float))
 612                             {
 613                                 value.GetScalar() = (float) data.GetFloat(&offset);
 614                                 success = true;
 615                             }
 616                             else if (byte_size == sizeof(double))
 617                             {
 618                                 value.GetScalar() = (double) data.GetDouble(&offset);
 619                                 success = true;
 620                             }
 621                         }
 622                     }
 623                 }
 624             }
 625         }
 626
 627         if (success)
 628             return_valobj_sp = ValueObjectConstResult::Create (thread.GetStackFrameAtIndex(0).get(),
 629                                                                value,
 630                                                                ConstString(""));
 631     }
 632     else if (type_flags & eTypeIsPointer)
 633     {
 634         unsigned r3_id = reg_ctx->GetRegisterInfoByName("r3", 0)->kinds[eRegisterKindLLDB];
 635         value.GetScalar() = (uint64_t)thread.GetRegisterContext()->ReadRegisterAsUnsigned(r3_id, 0);
 636         value.SetValueType(Value::eValueTypeScalar);
 637         return_valobj_sp = ValueObjectConstResult::Create (thread.GetStackFrameAtIndex(0).get(),
 638                                                            value,
 639                                                            ConstString(""));
 640     }
 641     else if (type_flags & eTypeIsVector)
 642     {
 643         const size_t byte_size = return_compiler_type.GetByteSize(nullptr);
 644         if (byte_size > 0)
 645         {
 646             const RegisterInfo *altivec_reg = reg_ctx->GetRegisterInfoByName("v2", 0);
 647             if (altivec_reg)
 648             {
 649                 if (byte_size <= altivec_reg->byte_size)
 650                 {
 651                     ProcessSP process_sp (thread.GetProcess());
 652                     if (process_sp)
 653                     {
 654                         std::unique_ptr<DataBufferHeap> heap_data_ap (new DataBufferHeap(byte_size, 0));
 655                         const ByteOrder byte_order = process_sp->GetByteOrder();
 656                         RegisterValue reg_value;
 657                         if (reg_ctx->ReadRegister(altivec_reg, reg_value))
 658                         {
 659                             Error error;
 660                             if (reg_value.GetAsMemoryData (altivec_reg,
 661                                                            heap_data_ap->GetBytes(),
 662                                                            heap_data_ap->GetByteSize(),
 663                                                            byte_order,
 664                                                            error))
 665                             {
 666                                 DataExtractor data (DataBufferSP (heap_data_ap.release()),
 667                                                     byte_order,
 668                                                     process_sp->GetTarget().GetArchitecture().GetAddressByteSize());
 669                                 return_valobj_sp = ValueObjectConstResult::Create (&thread,
 670                                                                                    return_compiler_type,
 671                                                                                    ConstString(""),
 672                                                                                    data);
 673                             }
 674                         }
 675                     }
 676                 }
 677             }
 678         }
 679     }
 680
 681     return return_valobj_sp;
 682 }
 683
 684 ValueObjectSP
 685 ABISysV_ppc::GetReturnValueObjectImpl (Thread &thread, CompilerType &return_compiler_type) const
 686 {
 687     ValueObjectSP return_valobj_sp;
 688
 689     if (!return_compiler_type)
 690         return return_valobj_sp;
 691
 692     ExecutionContext exe_ctx (thread.shared_from_this());
 693     return_valobj_sp = GetReturnValueObjectSimple(thread, return_compiler_type);
 694     if (return_valobj_sp)
 695         return return_valobj_sp;
 696
 697     RegisterContextSP reg_ctx_sp = thread.GetRegisterContext();
 698     if (!reg_ctx_sp)
 699         return return_valobj_sp;
 700
 701     const size_t bit_width = return_compiler_type.GetBitSize(&thread);
 702     if (return_compiler_type.IsAggregateType())
 703     {
 704         Target *target = exe_ctx.GetTargetPtr();
 705         bool is_memory = true;
 706         if (bit_width <= 128)
 707         {
 708             ByteOrder target_byte_order = target->GetArchitecture().GetByteOrder();
 709             DataBufferSP data_sp (new DataBufferHeap(16, 0));
 710             DataExtractor return_ext (data_sp,
 711                                       target_byte_order,
 712                                       target->GetArchitecture().GetAddressByteSize());
 713
 714             const RegisterInfo *r3_info = reg_ctx_sp->GetRegisterInfoByName("r3", 0);
 715             const RegisterInfo *rdx_info = reg_ctx_sp->GetRegisterInfoByName("rdx", 0);
 716
 717             RegisterValue r3_value, rdx_value;
 718             reg_ctx_sp->ReadRegister (r3_info, r3_value);
 719             reg_ctx_sp->ReadRegister (rdx_info, rdx_value);
 720
 721             DataExtractor r3_data, rdx_data;
 722
 723             r3_value.GetData(r3_data);
 724             rdx_value.GetData(rdx_data);
 725
 726             uint32_t fp_bytes = 0;       // Tracks how much of the xmm registers we've consumed so far
 727             uint32_t integer_bytes = 0;  // Tracks how much of the r3/rds registers we've consumed so far
 728
 729             const uint32_t num_children = return_compiler_type.GetNumFields ();
 730
 731             // Since we are in the small struct regime, assume we are not in memory.
 732             is_memory = false;
 733
 734             for (uint32_t idx = 0; idx < num_children; idx++)
 735             {
 736                 std::string name;
 737                 uint64_t field_bit_offset = 0;
 738                 bool is_signed;
 739                 bool is_complex;
 740                 uint32_t count;
 741
 742                 CompilerType field_compiler_type = return_compiler_type.GetFieldAtIndex(idx, name, &field_bit_offset, nullptr, nullptr);
 743                 const size_t field_bit_width = field_compiler_type.GetBitSize(&thread);
 744
 745                 // If there are any unaligned fields, this is stored in memory.
 746                 if (field_bit_offset % field_bit_width != 0)
 747                 {
 748                     is_memory = true;
 749                     break;
 750                 }
 751
 752                 uint32_t field_byte_width = field_bit_width/8;
 753                 uint32_t field_byte_offset = field_bit_offset/8;
 754
 755                 DataExtractor *copy_from_extractor = nullptr;
 756                 uint32_t       copy_from_offset    = 0;
 757
 758                 if (field_compiler_type.IsIntegerOrEnumerationType (is_signed) || field_compiler_type.IsPointerType ())
 759                 {
 760                     if (integer_bytes < 8)
 761                     {
 762                         if (integer_bytes + field_byte_width <= 8)
 763                         {
 764                             // This is in RAX, copy from register to our result structure:
 765                             copy_from_extractor = &r3_data;
 766                             copy_from_offset = integer_bytes;
 767                             integer_bytes += field_byte_width;
 768                         }
 769                         else
 770                         {
 771                             // The next field wouldn't fit in the remaining space, so we pushed it to rdx.
 772                             copy_from_extractor = &rdx_data;
 773                             copy_from_offset = 0;
 774                             integer_bytes = 8 + field_byte_width;
 775                         }
 776                     }
 777                     else if (integer_bytes + field_byte_width <= 16)
 778                     {
 779                         copy_from_extractor = &rdx_data;
 780                         copy_from_offset = integer_bytes - 8;
 781                         integer_bytes += field_byte_width;
 782                     }
 783                     else
 784                     {
 785                         // The last field didn't fit.  I can't see how that would happen w/o the overall size being
 786                         // greater than 16 bytes.  For now, return a nullptr return value object.
 787                         return return_valobj_sp;
 788                     }
 789                 }
 790                 else if (field_compiler_type.IsFloatingPointType (count, is_complex))
 791                 {
 792                     // Structs with long doubles are always passed in memory.
 793                     if (field_bit_width == 128)
 794                     {
 795                         is_memory = true;
 796                         break;
 797                     }
 798                     else if (field_bit_width == 64)
 799                     {
 800                         copy_from_offset = 0;
 801                         fp_bytes += field_byte_width;
 802                     }
 803                     else if (field_bit_width == 32)
 804                     {
 805                         // This one is kind of complicated.  If we are in an "eightbyte" with another float, we'll
 806                         // be stuffed into an xmm register with it.  If we are in an "eightbyte" with one or more ints,
 807                         // then we will be stuffed into the appropriate GPR with them.
 808                         bool in_gpr;
 809                         if (field_byte_offset % 8 == 0)
 810                         {
 811                             // We are at the beginning of one of the eightbytes, so check the next element (if any)
 812                             if (idx == num_children - 1)
 813                                 in_gpr = false;
 814                             else
 815                             {
 816                                 uint64_t next_field_bit_offset = 0;
 817                                 CompilerType next_field_compiler_type = return_compiler_type.GetFieldAtIndex (idx + 1,
 818                                                                                                         name,
 819                                                                                                         &next_field_bit_offset,
 820                                                                                                         nullptr,
 821                                                                                                         nullptr);
 822                                 if (next_field_compiler_type.IsIntegerOrEnumerationType (is_signed))
 823                                     in_gpr = true;
 824                                 else
 825                                 {
 826                                     copy_from_offset = 0;
 827                                     in_gpr = false;
 828                                 }
 829                             }
 830                         }
 831                         else if (field_byte_offset % 4 == 0)
 832                         {
 833                             // We are inside of an eightbyte, so see if the field before us is floating point:
 834                             // This could happen if somebody put padding in the structure.
 835                             if (idx == 0)
 836                                 in_gpr = false;
 837                             else
 838                             {
 839                                 uint64_t prev_field_bit_offset = 0;
 840                                 CompilerType prev_field_compiler_type = return_compiler_type.GetFieldAtIndex (idx - 1,
 841                                                                                                         name,
 842                                                                                                         &prev_field_bit_offset,
 843                                                                                                         nullptr,
 844                                                                                                         nullptr);
 845                                 if (prev_field_compiler_type.IsIntegerOrEnumerationType (is_signed))
 846                                     in_gpr = true;
 847                                 else
 848                                 {
 849                                     copy_from_offset = 4;
 850                                     in_gpr = false;
 851                                 }
 852                             }
 853                         }
 854                         else
 855                         {
 856                             is_memory = true;
 857                             continue;
 858                         }
 859
 860                         // Okay, we've figured out whether we are in GPR or XMM, now figure out which one.
 861                         if (in_gpr)
 862                         {
 863                             if (integer_bytes < 8)
 864                             {
 865                                 // This is in RAX, copy from register to our result structure:
 866                                 copy_from_extractor = &r3_data;
 867                                 copy_from_offset = integer_bytes;
 868                                 integer_bytes += field_byte_width;
 869                             }
 870                             else
 871                             {
 872                                 copy_from_extractor = &rdx_data;
 873                                 copy_from_offset = integer_bytes - 8;
 874                                 integer_bytes += field_byte_width;
 875                             }
 876                         }
 877                         else
 878                         {
 879                             fp_bytes += field_byte_width;
 880                         }
 881                     }
 882                 }
 883
 884                 // These two tests are just sanity checks.  If I somehow get the
 885                 // type calculation wrong above it is better to just return nothing
 886                 // than to assert or crash.
 887                 if (!copy_from_extractor)
 888                     return return_valobj_sp;
 889                 if (copy_from_offset + field_byte_width > copy_from_extractor->GetByteSize())
 890                     return return_valobj_sp;
 891
 892                 copy_from_extractor->CopyByteOrderedData (copy_from_offset,
 893                                                           field_byte_width,
 894                                                           data_sp->GetBytes() + field_byte_offset,
 895                                                           field_byte_width,
 896                                                           target_byte_order);
 897             }
 898
 899             if (!is_memory)
 900             {
 901                 // The result is in our data buffer.  Let's make a variable object out of it:
 902                 return_valobj_sp = ValueObjectConstResult::Create (&thread,
 903                                                                    return_compiler_type,
 904                                                                    ConstString(""),
 905                                                                    return_ext);
 906             }
 907         }
 908
 909         // FIXME: This is just taking a guess, r3 may very well no longer hold the return storage location.
 910         // If we are going to do this right, when we make a new frame we should check to see if it uses a memory
 911         // return, and if we are at the first instruction and if so stash away the return location.  Then we would
 912         // only return the memory return value if we know it is valid.
 913
 914         if (is_memory)
 915         {
 916             unsigned r3_id = reg_ctx_sp->GetRegisterInfoByName("r3", 0)->kinds[eRegisterKindLLDB];
 917             lldb::addr_t storage_addr = (uint64_t)thread.GetRegisterContext()->ReadRegisterAsUnsigned(r3_id, 0);
 918             return_valobj_sp = ValueObjectMemory::Create(&thread,
 919                                                          "",
 920                                                          Address(storage_addr, nullptr),
 921                                                          return_compiler_type);
 922         }
 923     }
 924
 925     return return_valobj_sp;
 926 }
 927
 928 bool
 929 ABISysV_ppc::CreateFunctionEntryUnwindPlan (UnwindPlan &unwind_plan)
 930 {
 931     unwind_plan.Clear();
 932     unwind_plan.SetRegisterKind (eRegisterKindDWARF);
 933
 934     uint32_t lr_reg_num = dwarf_lr;
 935     uint32_t sp_reg_num = dwarf_r1;
 936     uint32_t pc_reg_num = dwarf_pc;
 937
 938     UnwindPlan::RowSP row(new UnwindPlan::Row);
 939
 940     // Our Call Frame Address is the stack pointer value
 941     row->GetCFAValue().SetIsRegisterPlusOffset (sp_reg_num, 0);
 942
 943     // The previous PC is in the LR
 944     row->SetRegisterLocationToRegister(pc_reg_num, lr_reg_num, true);
 945     unwind_plan.AppendRow (row);
 946
 947     // All other registers are the same.
 948
 949     unwind_plan.SetSourceName ("ppc at-func-entry default");
 950     unwind_plan.SetSourcedFromCompiler (eLazyBoolNo);
 951
 952     return true;
 953 }
 954
 955 bool
 956 ABISysV_ppc::CreateDefaultUnwindPlan (UnwindPlan &unwind_plan)
 957 {
 958     unwind_plan.Clear();
 959     unwind_plan.SetRegisterKind (eRegisterKindDWARF);
 960
 961     uint32_t sp_reg_num = dwarf_r1;
 962     uint32_t pc_reg_num = dwarf_lr;
 963
 964     UnwindPlan::RowSP row(new UnwindPlan::Row);
 965
 966     const int32_t ptr_size = 4;
 967     row->GetCFAValue().SetIsRegisterDereferenced (sp_reg_num);
 968
 969     row->SetRegisterLocationToAtCFAPlusOffset(pc_reg_num, ptr_size * 1, true);
 970     row->SetRegisterLocationToIsCFAPlusOffset(sp_reg_num, 0, true);
 971
 972     unwind_plan.AppendRow (row);
 973     unwind_plan.SetSourceName ("ppc default unwind plan");
 974     unwind_plan.SetSourcedFromCompiler (eLazyBoolNo);
 975     unwind_plan.SetUnwindPlanValidAtAllInstructions (eLazyBoolNo);
 976     unwind_plan.SetReturnAddressRegister(dwarf_lr);
 977     return true;
 978 }
 979
 980 bool
 981 ABISysV_ppc::RegisterIsVolatile (const RegisterInfo *reg_info)
 982 {
 983     return !RegisterIsCalleeSaved (reg_info);
 984 }
 985
 986 // See "Register Usage" in the
 987 // "System V Application Binary Interface"
 988 // "64-bit PowerPC ELF Application Binary Interface Supplement"
 989 // current version is 1.9 released 2004 at http://refspecs.linuxfoundation.org/ELF/ppc/PPC-elf64abi-1.9.pdf
 990
 991 bool
 992 ABISysV_ppc::RegisterIsCalleeSaved (const RegisterInfo *reg_info)
 993 {
 994     if (reg_info)
 995     {
 996         // Preserved registers are :
 997         //    r1,r2,r13-r31
 998         //    f14-f31 (not yet)
 999         //    v20-v31 (not yet)
1000         //    vrsave (not yet)
1001
1002         const char *name = reg_info->name;
1003         if (name[0] == 'r')
1004         {
1005             if ((name[1] == '1' || name[1] == '2') && name[2] == '\0')
1006                 return true;
1007             if (name[1] == '1' && name[2] > '2')
1008                 return true;
1009             if ((name[1] == '2' || name[1] == '3') && name[2] != '\0')
1010                 return true;
1011         }
1012
1013         if (name[0] == 'f' && name[1] >= '0' && name[1] <= '9')
1014         {
1015             if (name[3] == '1' && name[4] >= '4')
1016                 return true;
1017             if ((name[3] == '2' || name[3] == '3') && name[4] != '\0')
1018                 return true;
1019         }
1020
1021         if (name[0] == 's' && name[1] == 'p' && name[2] == '\0')   // sp
1022             return true;
1023         if (name[0] == 'f' && name[1] == 'p' && name[2] == '\0')   // fp
1024             return true;
1025         if (name[0] == 'p' && name[1] == 'c' && name[2] == '\0')   // pc
1026             return true;
1027     }
1028     return false;
1029 }
1030
1031 void
1032 ABISysV_ppc::Initialize()
1033 {
1034     PluginManager::RegisterPlugin (GetPluginNameStatic(),
1035                                    "System V ABI for ppc targets",
1036                                    CreateInstance);
1037 }
1038
1039 void
1040 ABISysV_ppc::Terminate()
1041 {
1042     PluginManager::UnregisterPlugin (CreateInstance);
1043 }
1044
1045 lldb_private::ConstString
1046 ABISysV_ppc::GetPluginNameStatic()
1047 {
1048     static ConstString g_name("sysv-ppc");
1049     return g_name;
1050 }
1051
1052 //------------------------------------------------------------------
1053 // PluginInterface protocol
1054 //------------------------------------------------------------------
1055
1056 lldb_private::ConstString
1057 ABISysV_ppc::GetPluginName()
1058 {
1059     return GetPluginNameStatic();
1060 }
1061
1062 uint32_t
1063 ABISysV_ppc::GetPluginVersion()
1064 {
1065     return 1;
1066 }