1 //===-- ABISysV_s390x.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_s390x.h" 10 11 #include "llvm/ADT/STLExtras.h" 12 #include "llvm/ADT/Triple.h" 13 14 #include "lldb/Core/Module.h" 15 #include "lldb/Core/PluginManager.h" 16 #include "lldb/Core/Value.h" 17 #include "lldb/Core/ValueObjectConstResult.h" 18 #include "lldb/Core/ValueObjectMemory.h" 19 #include "lldb/Core/ValueObjectRegister.h" 20 #include "lldb/Symbol/UnwindPlan.h" 21 #include "lldb/Target/Process.h" 22 #include "lldb/Target/RegisterContext.h" 23 #include "lldb/Target/StackFrame.h" 24 #include "lldb/Target/Target.h" 25 #include "lldb/Target/Thread.h" 26 #include "lldb/Utility/ConstString.h" 27 #include "lldb/Utility/DataExtractor.h" 28 #include "lldb/Utility/LLDBLog.h" 29 #include "lldb/Utility/Log.h" 30 #include "lldb/Utility/RegisterValue.h" 31 #include "lldb/Utility/Status.h" 32 #include <optional> 33 34 using namespace lldb; 35 using namespace lldb_private; 36 37 LLDB_PLUGIN_DEFINE_ADV(ABISysV_s390x, ABISystemZ) 38 39 enum dwarf_regnums { 40 // General Purpose Registers 41 dwarf_r0_s390x = 0, 42 dwarf_r1_s390x, 43 dwarf_r2_s390x, 44 dwarf_r3_s390x, 45 dwarf_r4_s390x, 46 dwarf_r5_s390x, 47 dwarf_r6_s390x, 48 dwarf_r7_s390x, 49 dwarf_r8_s390x, 50 dwarf_r9_s390x, 51 dwarf_r10_s390x, 52 dwarf_r11_s390x, 53 dwarf_r12_s390x, 54 dwarf_r13_s390x, 55 dwarf_r14_s390x, 56 dwarf_r15_s390x, 57 // Floating Point Registers / Vector Registers 0-15 58 dwarf_f0_s390x = 16, 59 dwarf_f2_s390x, 60 dwarf_f4_s390x, 61 dwarf_f6_s390x, 62 dwarf_f1_s390x, 63 dwarf_f3_s390x, 64 dwarf_f5_s390x, 65 dwarf_f7_s390x, 66 dwarf_f8_s390x, 67 dwarf_f10_s390x, 68 dwarf_f12_s390x, 69 dwarf_f14_s390x, 70 dwarf_f9_s390x, 71 dwarf_f11_s390x, 72 dwarf_f13_s390x, 73 dwarf_f15_s390x, 74 // Access Registers 75 dwarf_acr0_s390x = 48, 76 dwarf_acr1_s390x, 77 dwarf_acr2_s390x, 78 dwarf_acr3_s390x, 79 dwarf_acr4_s390x, 80 dwarf_acr5_s390x, 81 dwarf_acr6_s390x, 82 dwarf_acr7_s390x, 83 dwarf_acr8_s390x, 84 dwarf_acr9_s390x, 85 dwarf_acr10_s390x, 86 dwarf_acr11_s390x, 87 dwarf_acr12_s390x, 88 dwarf_acr13_s390x, 89 dwarf_acr14_s390x, 90 dwarf_acr15_s390x, 91 // Program Status Word 92 dwarf_pswm_s390x = 64, 93 dwarf_pswa_s390x, 94 // Vector Registers 16-31 95 dwarf_v16_s390x = 68, 96 dwarf_v18_s390x, 97 dwarf_v20_s390x, 98 dwarf_v22_s390x, 99 dwarf_v17_s390x, 100 dwarf_v19_s390x, 101 dwarf_v21_s390x, 102 dwarf_v23_s390x, 103 dwarf_v24_s390x, 104 dwarf_v26_s390x, 105 dwarf_v28_s390x, 106 dwarf_v30_s390x, 107 dwarf_v25_s390x, 108 dwarf_v27_s390x, 109 dwarf_v29_s390x, 110 dwarf_v31_s390x, 111 }; 112 113 // RegisterKind: EHFrame, DWARF, Generic, Process Plugin, LLDB 114 115 #define DEFINE_REG(name, size, alt, generic) \ 116 { \ 117 #name, alt, size, 0, eEncodingUint, eFormatHex, \ 118 {dwarf_##name##_s390x, dwarf_##name##_s390x, generic, \ 119 LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM }, \ 120 nullptr, nullptr, \ 121 } 122 123 static const RegisterInfo g_register_infos[] = { 124 DEFINE_REG(r0, 8, nullptr, LLDB_INVALID_REGNUM), 125 DEFINE_REG(r1, 8, nullptr, LLDB_INVALID_REGNUM), 126 DEFINE_REG(r2, 8, nullptr, LLDB_REGNUM_GENERIC_ARG1), 127 DEFINE_REG(r3, 8, nullptr, LLDB_REGNUM_GENERIC_ARG2), 128 DEFINE_REG(r4, 8, nullptr, LLDB_REGNUM_GENERIC_ARG3), 129 DEFINE_REG(r5, 8, nullptr, LLDB_REGNUM_GENERIC_ARG4), 130 DEFINE_REG(r6, 8, nullptr, LLDB_REGNUM_GENERIC_ARG5), 131 DEFINE_REG(r7, 8, nullptr, LLDB_INVALID_REGNUM), 132 DEFINE_REG(r8, 8, nullptr, LLDB_INVALID_REGNUM), 133 DEFINE_REG(r9, 8, nullptr, LLDB_INVALID_REGNUM), 134 DEFINE_REG(r10, 8, nullptr, LLDB_INVALID_REGNUM), 135 DEFINE_REG(r11, 8, nullptr, LLDB_REGNUM_GENERIC_FP), 136 DEFINE_REG(r12, 8, nullptr, LLDB_INVALID_REGNUM), 137 DEFINE_REG(r13, 8, nullptr, LLDB_INVALID_REGNUM), 138 DEFINE_REG(r14, 8, nullptr, LLDB_INVALID_REGNUM), 139 DEFINE_REG(r15, 8, "sp", LLDB_REGNUM_GENERIC_SP), 140 DEFINE_REG(acr0, 4, nullptr, LLDB_INVALID_REGNUM), 141 DEFINE_REG(acr1, 4, nullptr, LLDB_INVALID_REGNUM), 142 DEFINE_REG(acr2, 4, nullptr, LLDB_INVALID_REGNUM), 143 DEFINE_REG(acr3, 4, nullptr, LLDB_INVALID_REGNUM), 144 DEFINE_REG(acr4, 4, nullptr, LLDB_INVALID_REGNUM), 145 DEFINE_REG(acr5, 4, nullptr, LLDB_INVALID_REGNUM), 146 DEFINE_REG(acr6, 4, nullptr, LLDB_INVALID_REGNUM), 147 DEFINE_REG(acr7, 4, nullptr, LLDB_INVALID_REGNUM), 148 DEFINE_REG(acr8, 4, nullptr, LLDB_INVALID_REGNUM), 149 DEFINE_REG(acr9, 4, nullptr, LLDB_INVALID_REGNUM), 150 DEFINE_REG(acr10, 4, nullptr, LLDB_INVALID_REGNUM), 151 DEFINE_REG(acr11, 4, nullptr, LLDB_INVALID_REGNUM), 152 DEFINE_REG(acr12, 4, nullptr, LLDB_INVALID_REGNUM), 153 DEFINE_REG(acr13, 4, nullptr, LLDB_INVALID_REGNUM), 154 DEFINE_REG(acr14, 4, nullptr, LLDB_INVALID_REGNUM), 155 DEFINE_REG(acr15, 4, nullptr, LLDB_INVALID_REGNUM), 156 DEFINE_REG(pswm, 8, nullptr, LLDB_REGNUM_GENERIC_FLAGS), 157 DEFINE_REG(pswa, 8, nullptr, LLDB_REGNUM_GENERIC_PC), 158 DEFINE_REG(f0, 8, nullptr, LLDB_INVALID_REGNUM), 159 DEFINE_REG(f1, 8, nullptr, LLDB_INVALID_REGNUM), 160 DEFINE_REG(f2, 8, nullptr, LLDB_INVALID_REGNUM), 161 DEFINE_REG(f3, 8, nullptr, LLDB_INVALID_REGNUM), 162 DEFINE_REG(f4, 8, nullptr, LLDB_INVALID_REGNUM), 163 DEFINE_REG(f5, 8, nullptr, LLDB_INVALID_REGNUM), 164 DEFINE_REG(f6, 8, nullptr, LLDB_INVALID_REGNUM), 165 DEFINE_REG(f7, 8, nullptr, LLDB_INVALID_REGNUM), 166 DEFINE_REG(f8, 8, nullptr, LLDB_INVALID_REGNUM), 167 DEFINE_REG(f9, 8, nullptr, LLDB_INVALID_REGNUM), 168 DEFINE_REG(f10, 8, nullptr, LLDB_INVALID_REGNUM), 169 DEFINE_REG(f11, 8, nullptr, LLDB_INVALID_REGNUM), 170 DEFINE_REG(f12, 8, nullptr, LLDB_INVALID_REGNUM), 171 DEFINE_REG(f13, 8, nullptr, LLDB_INVALID_REGNUM), 172 DEFINE_REG(f14, 8, nullptr, LLDB_INVALID_REGNUM), 173 DEFINE_REG(f15, 8, nullptr, LLDB_INVALID_REGNUM), 174 }; 175 176 static const uint32_t k_num_register_infos = std::size(g_register_infos); 177 178 const lldb_private::RegisterInfo * 179 ABISysV_s390x::GetRegisterInfoArray(uint32_t &count) { 180 count = k_num_register_infos; 181 return g_register_infos; 182 } 183 184 size_t ABISysV_s390x::GetRedZoneSize() const { return 0; } 185 186 // Static Functions 187 188 ABISP 189 ABISysV_s390x::CreateInstance(lldb::ProcessSP process_sp, const ArchSpec &arch) { 190 if (arch.GetTriple().getArch() == llvm::Triple::systemz) { 191 return ABISP(new ABISysV_s390x(std::move(process_sp), MakeMCRegisterInfo(arch))); 192 } 193 return ABISP(); 194 } 195 196 bool ABISysV_s390x::PrepareTrivialCall(Thread &thread, addr_t sp, 197 addr_t func_addr, addr_t return_addr, 198 llvm::ArrayRef<addr_t> args) const { 199 Log *log = GetLog(LLDBLog::Expressions); 200 201 if (log) { 202 StreamString s; 203 s.Printf("ABISysV_s390x::PrepareTrivialCall (tid = 0x%" PRIx64 204 ", sp = 0x%" PRIx64 ", func_addr = 0x%" PRIx64 205 ", return_addr = 0x%" PRIx64, 206 thread.GetID(), (uint64_t)sp, (uint64_t)func_addr, 207 (uint64_t)return_addr); 208 209 for (size_t i = 0; i < args.size(); ++i) 210 s.Printf(", arg%" PRIu64 " = 0x%" PRIx64, static_cast<uint64_t>(i + 1), 211 args[i]); 212 s.PutCString(")"); 213 log->PutString(s.GetString()); 214 } 215 216 RegisterContext *reg_ctx = thread.GetRegisterContext().get(); 217 if (!reg_ctx) 218 return false; 219 220 const RegisterInfo *pc_reg_info = 221 reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC); 222 const RegisterInfo *sp_reg_info = 223 reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP); 224 const RegisterInfo *ra_reg_info = reg_ctx->GetRegisterInfoByName("r14", 0); 225 ProcessSP process_sp(thread.GetProcess()); 226 227 // Allocate a new stack frame and space for stack arguments if necessary 228 229 addr_t arg_pos = 0; 230 if (args.size() > 5) { 231 sp -= 8 * (args.size() - 5); 232 arg_pos = sp; 233 } 234 235 sp -= 160; 236 237 // Process arguments 238 239 for (size_t i = 0; i < args.size(); ++i) { 240 if (i < 5) { 241 const RegisterInfo *reg_info = reg_ctx->GetRegisterInfo( 242 eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG1 + i); 243 LLDB_LOGF(log, "About to write arg%" PRIu64 " (0x%" PRIx64 ") into %s", 244 static_cast<uint64_t>(i + 1), args[i], reg_info->name); 245 if (!reg_ctx->WriteRegisterFromUnsigned(reg_info, args[i])) 246 return false; 247 } else { 248 Status error; 249 LLDB_LOGF(log, "About to write arg%" PRIu64 " (0x%" PRIx64 ") onto stack", 250 static_cast<uint64_t>(i + 1), args[i]); 251 if (!process_sp->WritePointerToMemory(arg_pos, args[i], error)) 252 return false; 253 arg_pos += 8; 254 } 255 } 256 257 // %r14 is set to the return address 258 259 LLDB_LOGF(log, "Writing RA: 0x%" PRIx64, (uint64_t)return_addr); 260 261 if (!reg_ctx->WriteRegisterFromUnsigned(ra_reg_info, return_addr)) 262 return false; 263 264 // %r15 is set to the actual stack value. 265 266 LLDB_LOGF(log, "Writing SP: 0x%" PRIx64, (uint64_t)sp); 267 268 if (!reg_ctx->WriteRegisterFromUnsigned(sp_reg_info, sp)) 269 return false; 270 271 // %pc is set to the address of the called function. 272 273 LLDB_LOGF(log, "Writing PC: 0x%" PRIx64, (uint64_t)func_addr); 274 275 if (!reg_ctx->WriteRegisterFromUnsigned(pc_reg_info, func_addr)) 276 return false; 277 278 return true; 279 } 280 281 static bool ReadIntegerArgument(Scalar &scalar, unsigned int bit_width, 282 bool is_signed, Thread &thread, 283 uint32_t *argument_register_ids, 284 unsigned int ¤t_argument_register, 285 addr_t ¤t_stack_argument) { 286 if (bit_width > 64) 287 return false; // Scalar can't hold large integer arguments 288 289 if (current_argument_register < 5) { 290 scalar = thread.GetRegisterContext()->ReadRegisterAsUnsigned( 291 argument_register_ids[current_argument_register], 0); 292 current_argument_register++; 293 if (is_signed) 294 scalar.SignExtend(bit_width); 295 } else { 296 uint32_t byte_size = (bit_width + (8 - 1)) / 8; 297 Status error; 298 if (thread.GetProcess()->ReadScalarIntegerFromMemory( 299 current_stack_argument + 8 - byte_size, byte_size, is_signed, 300 scalar, error)) { 301 current_stack_argument += 8; 302 return true; 303 } 304 return false; 305 } 306 return true; 307 } 308 309 bool ABISysV_s390x::GetArgumentValues(Thread &thread, ValueList &values) const { 310 unsigned int num_values = values.GetSize(); 311 unsigned int value_index; 312 313 // Extract the register context so we can read arguments from registers 314 315 RegisterContext *reg_ctx = thread.GetRegisterContext().get(); 316 317 if (!reg_ctx) 318 return false; 319 320 // Get the pointer to the first stack argument so we have a place to start 321 // when reading data 322 323 addr_t sp = reg_ctx->GetSP(0); 324 325 if (!sp) 326 return false; 327 328 addr_t current_stack_argument = sp + 160; 329 330 uint32_t argument_register_ids[5]; 331 332 argument_register_ids[0] = 333 reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG1) 334 ->kinds[eRegisterKindLLDB]; 335 argument_register_ids[1] = 336 reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG2) 337 ->kinds[eRegisterKindLLDB]; 338 argument_register_ids[2] = 339 reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG3) 340 ->kinds[eRegisterKindLLDB]; 341 argument_register_ids[3] = 342 reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG4) 343 ->kinds[eRegisterKindLLDB]; 344 argument_register_ids[4] = 345 reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG5) 346 ->kinds[eRegisterKindLLDB]; 347 348 unsigned int current_argument_register = 0; 349 350 for (value_index = 0; value_index < num_values; ++value_index) { 351 Value *value = values.GetValueAtIndex(value_index); 352 353 if (!value) 354 return false; 355 356 // We currently only support extracting values with Clang QualTypes. Do we 357 // care about others? 358 CompilerType compiler_type = value->GetCompilerType(); 359 std::optional<uint64_t> bit_size = compiler_type.GetBitSize(&thread); 360 if (!bit_size) 361 return false; 362 bool is_signed; 363 364 if (compiler_type.IsIntegerOrEnumerationType(is_signed)) { 365 ReadIntegerArgument(value->GetScalar(), *bit_size, is_signed, thread, 366 argument_register_ids, current_argument_register, 367 current_stack_argument); 368 } else if (compiler_type.IsPointerType()) { 369 ReadIntegerArgument(value->GetScalar(), *bit_size, false, thread, 370 argument_register_ids, current_argument_register, 371 current_stack_argument); 372 } 373 } 374 375 return true; 376 } 377 378 Status ABISysV_s390x::SetReturnValueObject(lldb::StackFrameSP &frame_sp, 379 lldb::ValueObjectSP &new_value_sp) { 380 Status error; 381 if (!new_value_sp) { 382 error.SetErrorString("Empty value object for return value."); 383 return error; 384 } 385 386 CompilerType compiler_type = new_value_sp->GetCompilerType(); 387 if (!compiler_type) { 388 error.SetErrorString("Null clang type for return value."); 389 return error; 390 } 391 392 Thread *thread = frame_sp->GetThread().get(); 393 394 bool is_signed; 395 uint32_t count; 396 bool is_complex; 397 398 RegisterContext *reg_ctx = thread->GetRegisterContext().get(); 399 400 bool set_it_simple = false; 401 if (compiler_type.IsIntegerOrEnumerationType(is_signed) || 402 compiler_type.IsPointerType()) { 403 const RegisterInfo *reg_info = reg_ctx->GetRegisterInfoByName("r2", 0); 404 405 DataExtractor data; 406 Status data_error; 407 size_t num_bytes = new_value_sp->GetData(data, data_error); 408 if (data_error.Fail()) { 409 error.SetErrorStringWithFormat( 410 "Couldn't convert return value to raw data: %s", 411 data_error.AsCString()); 412 return error; 413 } 414 lldb::offset_t offset = 0; 415 if (num_bytes <= 8) { 416 uint64_t raw_value = data.GetMaxU64(&offset, num_bytes); 417 418 if (reg_ctx->WriteRegisterFromUnsigned(reg_info, raw_value)) 419 set_it_simple = true; 420 } else { 421 error.SetErrorString("We don't support returning longer than 64 bit " 422 "integer values at present."); 423 } 424 } else if (compiler_type.IsFloatingPointType(count, is_complex)) { 425 if (is_complex) 426 error.SetErrorString( 427 "We don't support returning complex values at present"); 428 else { 429 std::optional<uint64_t> bit_width = 430 compiler_type.GetBitSize(frame_sp.get()); 431 if (!bit_width) { 432 error.SetErrorString("can't get type size"); 433 return error; 434 } 435 if (*bit_width <= 64) { 436 const RegisterInfo *f0_info = reg_ctx->GetRegisterInfoByName("f0", 0); 437 RegisterValue f0_value; 438 DataExtractor data; 439 Status data_error; 440 size_t num_bytes = new_value_sp->GetData(data, data_error); 441 if (data_error.Fail()) { 442 error.SetErrorStringWithFormat( 443 "Couldn't convert return value to raw data: %s", 444 data_error.AsCString()); 445 return error; 446 } 447 448 unsigned char buffer[8]; 449 ByteOrder byte_order = data.GetByteOrder(); 450 451 data.CopyByteOrderedData(0, num_bytes, buffer, 8, byte_order); 452 f0_value.SetBytes(buffer, 8, byte_order); 453 reg_ctx->WriteRegister(f0_info, f0_value); 454 set_it_simple = true; 455 } else { 456 // FIXME - don't know how to do long doubles yet. 457 error.SetErrorString( 458 "We don't support returning float values > 64 bits at present"); 459 } 460 } 461 } 462 463 if (!set_it_simple) { 464 // Okay we've got a structure or something that doesn't fit in a simple 465 // register. We should figure out where it really goes, but we don't 466 // support this yet. 467 error.SetErrorString("We only support setting simple integer and float " 468 "return types at present."); 469 } 470 471 return error; 472 } 473 474 ValueObjectSP ABISysV_s390x::GetReturnValueObjectSimple( 475 Thread &thread, CompilerType &return_compiler_type) const { 476 ValueObjectSP return_valobj_sp; 477 Value value; 478 479 if (!return_compiler_type) 480 return return_valobj_sp; 481 482 // value.SetContext (Value::eContextTypeClangType, return_value_type); 483 value.SetCompilerType(return_compiler_type); 484 485 RegisterContext *reg_ctx = thread.GetRegisterContext().get(); 486 if (!reg_ctx) 487 return return_valobj_sp; 488 489 const uint32_t type_flags = return_compiler_type.GetTypeInfo(); 490 if (type_flags & eTypeIsScalar) { 491 value.SetValueType(Value::ValueType::Scalar); 492 493 bool success = false; 494 if (type_flags & eTypeIsInteger) { 495 // Extract the register context so we can read arguments from registers. 496 std::optional<uint64_t> byte_size = 497 return_compiler_type.GetByteSize(&thread); 498 if (!byte_size) 499 return return_valobj_sp; 500 uint64_t raw_value = thread.GetRegisterContext()->ReadRegisterAsUnsigned( 501 reg_ctx->GetRegisterInfoByName("r2", 0), 0); 502 const bool is_signed = (type_flags & eTypeIsSigned) != 0; 503 switch (*byte_size) { 504 default: 505 break; 506 507 case sizeof(uint64_t): 508 if (is_signed) 509 value.GetScalar() = (int64_t)(raw_value); 510 else 511 value.GetScalar() = (uint64_t)(raw_value); 512 success = true; 513 break; 514 515 case sizeof(uint32_t): 516 if (is_signed) 517 value.GetScalar() = (int32_t)(raw_value & UINT32_MAX); 518 else 519 value.GetScalar() = (uint32_t)(raw_value & UINT32_MAX); 520 success = true; 521 break; 522 523 case sizeof(uint16_t): 524 if (is_signed) 525 value.GetScalar() = (int16_t)(raw_value & UINT16_MAX); 526 else 527 value.GetScalar() = (uint16_t)(raw_value & UINT16_MAX); 528 success = true; 529 break; 530 531 case sizeof(uint8_t): 532 if (is_signed) 533 value.GetScalar() = (int8_t)(raw_value & UINT8_MAX); 534 else 535 value.GetScalar() = (uint8_t)(raw_value & UINT8_MAX); 536 success = true; 537 break; 538 } 539 } else if (type_flags & eTypeIsFloat) { 540 if (type_flags & eTypeIsComplex) { 541 // Don't handle complex yet. 542 } else { 543 std::optional<uint64_t> byte_size = 544 return_compiler_type.GetByteSize(&thread); 545 if (byte_size && *byte_size <= sizeof(long double)) { 546 const RegisterInfo *f0_info = reg_ctx->GetRegisterInfoByName("f0", 0); 547 RegisterValue f0_value; 548 if (reg_ctx->ReadRegister(f0_info, f0_value)) { 549 DataExtractor data; 550 if (f0_value.GetData(data)) { 551 lldb::offset_t offset = 0; 552 if (*byte_size == sizeof(float)) { 553 value.GetScalar() = (float)data.GetFloat(&offset); 554 success = true; 555 } else if (*byte_size == sizeof(double)) { 556 value.GetScalar() = (double)data.GetDouble(&offset); 557 success = true; 558 } else if (*byte_size == sizeof(long double)) { 559 // Don't handle long double yet. 560 } 561 } 562 } 563 } 564 } 565 } 566 567 if (success) 568 return_valobj_sp = ValueObjectConstResult::Create( 569 thread.GetStackFrameAtIndex(0).get(), value, ConstString("")); 570 } else if (type_flags & eTypeIsPointer) { 571 unsigned r2_id = 572 reg_ctx->GetRegisterInfoByName("r2", 0)->kinds[eRegisterKindLLDB]; 573 value.GetScalar() = 574 (uint64_t)thread.GetRegisterContext()->ReadRegisterAsUnsigned(r2_id, 0); 575 value.SetValueType(Value::ValueType::Scalar); 576 return_valobj_sp = ValueObjectConstResult::Create( 577 thread.GetStackFrameAtIndex(0).get(), value, ConstString("")); 578 } 579 580 return return_valobj_sp; 581 } 582 583 ValueObjectSP ABISysV_s390x::GetReturnValueObjectImpl( 584 Thread &thread, CompilerType &return_compiler_type) const { 585 ValueObjectSP return_valobj_sp; 586 587 if (!return_compiler_type) 588 return return_valobj_sp; 589 590 ExecutionContext exe_ctx(thread.shared_from_this()); 591 return_valobj_sp = GetReturnValueObjectSimple(thread, return_compiler_type); 592 if (return_valobj_sp) 593 return return_valobj_sp; 594 595 RegisterContextSP reg_ctx_sp = thread.GetRegisterContext(); 596 if (!reg_ctx_sp) 597 return return_valobj_sp; 598 599 if (return_compiler_type.IsAggregateType()) { 600 // FIXME: This is just taking a guess, r2 may very well no longer hold the 601 // return storage location. 602 // If we are going to do this right, when we make a new frame we should 603 // check to see if it uses a memory return, and if we are at the first 604 // instruction and if so stash away the return location. Then we would 605 // only return the memory return value if we know it is valid. 606 607 unsigned r2_id = 608 reg_ctx_sp->GetRegisterInfoByName("r2", 0)->kinds[eRegisterKindLLDB]; 609 lldb::addr_t storage_addr = 610 (uint64_t)thread.GetRegisterContext()->ReadRegisterAsUnsigned(r2_id, 0); 611 return_valobj_sp = ValueObjectMemory::Create( 612 &thread, "", Address(storage_addr, nullptr), return_compiler_type); 613 } 614 615 return return_valobj_sp; 616 } 617 618 bool ABISysV_s390x::CreateFunctionEntryUnwindPlan(UnwindPlan &unwind_plan) { 619 unwind_plan.Clear(); 620 unwind_plan.SetRegisterKind(eRegisterKindDWARF); 621 622 UnwindPlan::RowSP row(new UnwindPlan::Row); 623 624 // Our Call Frame Address is the stack pointer value + 160 625 row->GetCFAValue().SetIsRegisterPlusOffset(dwarf_r15_s390x, 160); 626 627 // The previous PC is in r14 628 row->SetRegisterLocationToRegister(dwarf_pswa_s390x, dwarf_r14_s390x, true); 629 630 // All other registers are the same. 631 unwind_plan.AppendRow(row); 632 unwind_plan.SetSourceName("s390x at-func-entry default"); 633 unwind_plan.SetSourcedFromCompiler(eLazyBoolNo); 634 return true; 635 } 636 637 bool ABISysV_s390x::CreateDefaultUnwindPlan(UnwindPlan &unwind_plan) { 638 // There's really no default way to unwind on s390x. Trust the .eh_frame CFI, 639 // which should always be good. 640 return false; 641 } 642 643 bool ABISysV_s390x::GetFallbackRegisterLocation( 644 const RegisterInfo *reg_info, 645 UnwindPlan::Row::RegisterLocation &unwind_regloc) { 646 // If a volatile register is being requested, we don't want to forward the 647 // next frame's register contents up the stack -- the register is not 648 // retrievable at this frame. 649 if (RegisterIsVolatile(reg_info)) { 650 unwind_regloc.SetUndefined(); 651 return true; 652 } 653 654 return false; 655 } 656 657 bool ABISysV_s390x::RegisterIsVolatile(const RegisterInfo *reg_info) { 658 return !RegisterIsCalleeSaved(reg_info); 659 } 660 661 bool ABISysV_s390x::RegisterIsCalleeSaved(const RegisterInfo *reg_info) { 662 if (reg_info) { 663 // Preserved registers are : 664 // r6-r13, r15 665 // f8-f15 666 667 const char *name = reg_info->name; 668 if (name[0] == 'r') { 669 switch (name[1]) { 670 case '6': // r6 671 case '7': // r7 672 case '8': // r8 673 case '9': // r9 674 return name[2] == '\0'; 675 676 case '1': // r10, r11, r12, r13, r15 677 if ((name[2] >= '0' && name[2] <= '3') || name[2] == '5') 678 return name[3] == '\0'; 679 break; 680 681 default: 682 break; 683 } 684 } 685 if (name[0] == 'f') { 686 switch (name[1]) { 687 case '8': // r8 688 case '9': // r9 689 return name[2] == '\0'; 690 691 case '1': // r10, r11, r12, r13, r14, r15 692 if (name[2] >= '0' && name[2] <= '5') 693 return name[3] == '\0'; 694 break; 695 696 default: 697 break; 698 } 699 } 700 701 // Accept shorter-variant versions 702 if (name[0] == 's' && name[1] == 'p' && name[2] == '\0') // sp 703 return true; 704 if (name[0] == 'f' && name[1] == 'p' && name[2] == '\0') // fp 705 return true; 706 if (name[0] == 'p' && name[1] == 'c' && name[2] == '\0') // pc 707 return true; 708 } 709 return false; 710 } 711 712 void ABISysV_s390x::Initialize() { 713 PluginManager::RegisterPlugin( 714 GetPluginNameStatic(), "System V ABI for s390x targets", CreateInstance); 715 } 716 717 void ABISysV_s390x::Terminate() { 718 PluginManager::UnregisterPlugin(CreateInstance); 719 } 720