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
LLDB_PLUGIN_DEFINE(ABISysV_ppc64) const52 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
GetRedZoneSize() const65 size_t ABISysV_ppc64::GetRedZoneSize() const { return 224; }
66
GetByteOrder() const67 lldb::ByteOrder ABISysV_ppc64::GetByteOrder() const {
68 return GetProcessSP()->GetByteOrder();
69 }
70
71 // Static Functions
72
73 ABISP
CreateInstance(lldb::ProcessSP process_sp,const ArchSpec & arch)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
PrepareTrivialCall(Thread & thread,addr_t sp,addr_t func_addr,addr_t return_addr,llvm::ArrayRef<addr_t> args) const82 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
ReadIntegerArgument(Scalar & scalar,unsigned int bit_width,bool is_signed,Thread & thread,uint32_t * argument_register_ids,unsigned int & current_argument_register,addr_t & current_stack_argument)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 ¤t_argument_register,
204 addr_t ¤t_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
GetArgumentValues(Thread & thread,ValueList & values) const227 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
SetReturnValueObject(lldb::StackFrameSP & frame_sp,lldb::ValueObjectSP & new_value_sp)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
Register(Type ty,uint32_t index,uint32_t offs,RegisterContext * reg_ctx,ByteOrder byte_order)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
Register(Type ty,uint32_t index,RegisterContext * reg_ctx,ByteOrder byte_order)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
Register(uint32_t offs,RegisterContext * reg_ctx,ByteOrder byte_order)423 Register(uint32_t offs, RegisterContext *reg_ctx, ByteOrder byte_order)
424 : Register(GPR, offs / sizeof(uint64_t), offs, reg_ctx, byte_order) {}
425
Index() const426 uint32_t Index() const { return m_index; }
427
428 // register offset where data is located
Offs() const429 uint32_t Offs() const { return m_offs; }
430
431 // available bytes in this register
Avail() const432 uint32_t Avail() const { return m_avail; }
433
IsValid() const434 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
GetName() const443 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
GetRawData(uint64_t & raw_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
GetGPR(uint32_t index) const486 Register GetGPR(uint32_t index) const {
487 return Register(Register::GPR, index, m_reg_ctx, m_byte_order);
488 }
489
GetFPR(uint32_t index) const490 Register GetFPR(uint32_t index) const {
491 return Register(Register::FPR, index, m_reg_ctx, m_byte_order);
492 }
493
GetGPRByOffs(uint32_t offs) const494 Register GetGPRByOffs(uint32_t offs) const {
495 return Register(offs, m_reg_ctx, m_byte_order);
496 }
497
498 public:
499 // factory
Create(Thread & thread,CompilerType & type)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::createStringError(LOG_PREFIX
505 "Failed to get RegisterContext");
506
507 ProcessSP process_sp = thread.GetProcess();
508 if (!process_sp)
509 return llvm::createStringError(LOG_PREFIX "GetProcess() failed");
510
511 return ReturnValueExtractor(thread, type, reg_ctx, process_sp);
512 }
513
514 // main method: get value of the type specified at construction time
GetValue()515 ValueObjectSP GetValue() {
516 const uint32_t type_flags = m_type.GetTypeInfo();
517
518 // call the appropriate type handler
519 ValueSP value_sp;
520 ValueObjectSP valobj_sp;
521 if (type_flags & eTypeIsScalar) {
522 if (type_flags & eTypeIsInteger) {
523 value_sp = GetIntegerValue(0);
524 } else if (type_flags & eTypeIsFloat) {
525 if (type_flags & eTypeIsComplex) {
526 LLDB_LOG(m_log, LOG_PREFIX "Complex numbers are not supported yet");
527 return ValueObjectSP();
528 } else {
529 value_sp = GetFloatValue(m_type, 0);
530 }
531 }
532 } else if (type_flags & eTypeIsPointer) {
533 value_sp = GetPointerValue(0);
534 }
535
536 if (value_sp) {
537 valobj_sp = ValueObjectConstResult::Create(
538 m_thread.GetStackFrameAtIndex(0).get(), *value_sp, ConstString(""));
539 } else if (type_flags & eTypeIsVector) {
540 valobj_sp = GetVectorValueObject();
541 } else if (type_flags & eTypeIsStructUnion || type_flags & eTypeIsClass) {
542 valobj_sp = GetStructValueObject();
543 }
544
545 return valobj_sp;
546 }
547
548 private:
549 // data
550 Thread &m_thread;
551 CompilerType &m_type;
552 uint64_t m_byte_size;
553 std::unique_ptr<DataBufferHeap> m_data_up;
554 int32_t m_src_offs = 0;
555 int32_t m_dst_offs = 0;
556 bool m_packed = false;
557 Log *m_log = GetLog(LLDBLog::Expressions);
558 RegisterContext *m_reg_ctx;
559 ProcessSP m_process_sp;
560 ByteOrder m_byte_order;
561 uint32_t m_addr_size;
562
563 // methods
564
565 // constructor
ReturnValueExtractor(Thread & thread,CompilerType & type,RegisterContext * reg_ctx,ProcessSP process_sp)566 ReturnValueExtractor(Thread &thread, CompilerType &type,
567 RegisterContext *reg_ctx, ProcessSP process_sp)
568 : m_thread(thread), m_type(type),
569 m_byte_size(m_type.GetByteSize(&thread).value_or(0)),
570 m_data_up(new DataBufferHeap(m_byte_size, 0)), m_reg_ctx(reg_ctx),
571 m_process_sp(process_sp), m_byte_order(process_sp->GetByteOrder()),
572 m_addr_size(
573 process_sp->GetTarget().GetArchitecture().GetAddressByteSize()) {}
574
575 // build a new scalar value
NewScalarValue(CompilerType & type)576 ValueSP NewScalarValue(CompilerType &type) {
577 ValueSP value_sp(new Value);
578 value_sp->SetCompilerType(type);
579 value_sp->SetValueType(Value::ValueType::Scalar);
580 return value_sp;
581 }
582
583 // get an integer value in the specified register
GetIntegerValue(uint32_t reg_index)584 ValueSP GetIntegerValue(uint32_t reg_index) {
585 uint64_t raw_value;
586 auto reg = GetGPR(reg_index);
587 if (!reg.GetRawData(raw_value))
588 return ValueSP();
589
590 // build value from data
591 ValueSP value_sp(NewScalarValue(m_type));
592
593 uint32_t type_flags = m_type.GetTypeInfo();
594 bool is_signed = (type_flags & eTypeIsSigned) != 0;
595
596 switch (m_byte_size) {
597 case sizeof(uint64_t):
598 if (is_signed)
599 value_sp->GetScalar() = (int64_t)(raw_value);
600 else
601 value_sp->GetScalar() = (uint64_t)(raw_value);
602 break;
603
604 case sizeof(uint32_t):
605 if (is_signed)
606 value_sp->GetScalar() = (int32_t)(raw_value & UINT32_MAX);
607 else
608 value_sp->GetScalar() = (uint32_t)(raw_value & UINT32_MAX);
609 break;
610
611 case sizeof(uint16_t):
612 if (is_signed)
613 value_sp->GetScalar() = (int16_t)(raw_value & UINT16_MAX);
614 else
615 value_sp->GetScalar() = (uint16_t)(raw_value & UINT16_MAX);
616 break;
617
618 case sizeof(uint8_t):
619 if (is_signed)
620 value_sp->GetScalar() = (int8_t)(raw_value & UINT8_MAX);
621 else
622 value_sp->GetScalar() = (uint8_t)(raw_value & UINT8_MAX);
623 break;
624
625 default:
626 llvm_unreachable("Invalid integer size");
627 }
628
629 return value_sp;
630 }
631
632 // get a floating point value on the specified register
GetFloatValue(CompilerType & type,uint32_t reg_index)633 ValueSP GetFloatValue(CompilerType &type, uint32_t reg_index) {
634 uint64_t raw_data;
635 auto reg = GetFPR(reg_index);
636 if (!reg.GetRawData(raw_data))
637 return {};
638
639 // build value from data
640 ValueSP value_sp(NewScalarValue(type));
641
642 DataExtractor de(&raw_data, sizeof(raw_data), m_byte_order, m_addr_size);
643
644 offset_t offset = 0;
645 std::optional<uint64_t> byte_size = type.GetByteSize(m_process_sp.get());
646 if (!byte_size)
647 return {};
648 switch (*byte_size) {
649 case sizeof(float):
650 value_sp->GetScalar() = (float)de.GetDouble(&offset);
651 break;
652
653 case sizeof(double):
654 value_sp->GetScalar() = de.GetDouble(&offset);
655 break;
656
657 default:
658 llvm_unreachable("Invalid floating point size");
659 }
660
661 return value_sp;
662 }
663
664 // get pointer value from register
GetPointerValue(uint32_t reg_index)665 ValueSP GetPointerValue(uint32_t reg_index) {
666 uint64_t raw_data;
667 auto reg = GetGPR(reg_index);
668 if (!reg.GetRawData(raw_data))
669 return ValueSP();
670
671 // build value from raw data
672 ValueSP value_sp(NewScalarValue(m_type));
673 value_sp->GetScalar() = raw_data;
674 return value_sp;
675 }
676
677 // build the ValueObject from our data buffer
BuildValueObject()678 ValueObjectSP BuildValueObject() {
679 DataExtractor de(DataBufferSP(m_data_up.release()), m_byte_order,
680 m_addr_size);
681 return ValueObjectConstResult::Create(&m_thread, m_type, ConstString(""),
682 de);
683 }
684
685 // get a vector return value
GetVectorValueObject()686 ValueObjectSP GetVectorValueObject() {
687 const uint32_t MAX_VRS = 2;
688
689 // get first V register used to return values
690 const RegisterInfo *vr[MAX_VRS];
691 vr[0] = m_reg_ctx->GetRegisterInfoByName("vr2");
692 if (!vr[0]) {
693 LLDB_LOG(m_log, LOG_PREFIX "Failed to get vr2 RegisterInfo");
694 return ValueObjectSP();
695 }
696
697 const uint32_t vr_size = vr[0]->byte_size;
698 size_t vrs = 1;
699 if (m_byte_size > 2 * vr_size) {
700 LLDB_LOG(
701 m_log, LOG_PREFIX
702 "Returning vectors that don't fit in 2 VR regs is not supported");
703 return ValueObjectSP();
704 }
705
706 // load vr3, if needed
707 if (m_byte_size > vr_size) {
708 vrs++;
709 vr[1] = m_reg_ctx->GetRegisterInfoByName("vr3");
710 if (!vr[1]) {
711 LLDB_LOG(m_log, LOG_PREFIX "Failed to get vr3 RegisterInfo");
712 return ValueObjectSP();
713 }
714 }
715
716 // Get the whole contents of vector registers and let the logic here
717 // arrange the data properly.
718
719 RegisterValue vr_val[MAX_VRS];
720 Status error;
721 std::unique_ptr<DataBufferHeap> vr_data(
722 new DataBufferHeap(vrs * vr_size, 0));
723
724 for (uint32_t i = 0; i < vrs; i++) {
725 if (!m_reg_ctx->ReadRegister(vr[i], vr_val[i])) {
726 LLDB_LOG(m_log, LOG_PREFIX "Failed to read vector register contents");
727 return ValueObjectSP();
728 }
729 if (!vr_val[i].GetAsMemoryData(*vr[i], vr_data->GetBytes() + i * vr_size,
730 vr_size, m_byte_order, error)) {
731 LLDB_LOG(m_log, LOG_PREFIX "Failed to extract vector register bytes");
732 return ValueObjectSP();
733 }
734 }
735
736 // The compiler generated code seems to always put the vector elements at
737 // the end of the vector register, in case they don't occupy all of it.
738 // This offset variable handles this.
739 uint32_t offs = 0;
740 if (m_byte_size < vr_size)
741 offs = vr_size - m_byte_size;
742
743 // copy extracted data to our buffer
744 memcpy(m_data_up->GetBytes(), vr_data->GetBytes() + offs, m_byte_size);
745 return BuildValueObject();
746 }
747
748 // get a struct return value
GetStructValueObject()749 ValueObjectSP GetStructValueObject() {
750 // case 1: get from stack
751 if (m_byte_size > 2 * sizeof(uint64_t)) {
752 uint64_t addr;
753 auto reg = GetGPR(0);
754 if (!reg.GetRawData(addr))
755 return {};
756
757 Status error;
758 size_t rc = m_process_sp->ReadMemory(addr, m_data_up->GetBytes(),
759 m_byte_size, error);
760 if (rc != m_byte_size) {
761 LLDB_LOG(m_log, LOG_PREFIX "Failed to read memory pointed by r3");
762 return ValueObjectSP();
763 }
764 return BuildValueObject();
765 }
766
767 // get number of children
768 const bool omit_empty_base_classes = true;
769 auto n_or_err = m_type.GetNumChildren(omit_empty_base_classes, nullptr);
770 if (!n_or_err) {
771 LLDB_LOG_ERROR(m_log, n_or_err.takeError(), LOG_PREFIX "{0}");
772 return {};
773 }
774 uint32_t n = *n_or_err;
775 if (!n) {
776 LLDB_LOG(m_log, LOG_PREFIX "No children found in struct");
777 return {};
778 }
779
780 // case 2: homogeneous double or float aggregate
781 CompilerType elem_type;
782 if (m_type.IsHomogeneousAggregate(&elem_type)) {
783 uint32_t type_flags = elem_type.GetTypeInfo();
784 std::optional<uint64_t> elem_size =
785 elem_type.GetByteSize(m_process_sp.get());
786 if (!elem_size)
787 return {};
788 if (type_flags & eTypeIsComplex || !(type_flags & eTypeIsFloat)) {
789 LLDB_LOG(m_log,
790 LOG_PREFIX "Unexpected type found in homogeneous aggregate");
791 return {};
792 }
793
794 for (uint32_t i = 0; i < n; i++) {
795 ValueSP val_sp = GetFloatValue(elem_type, i);
796 if (!val_sp)
797 return {};
798
799 // copy to buffer
800 Status error;
801 size_t rc = val_sp->GetScalar().GetAsMemoryData(
802 m_data_up->GetBytes() + m_dst_offs, *elem_size, m_byte_order,
803 error);
804 if (rc != *elem_size) {
805 LLDB_LOG(m_log, LOG_PREFIX "Failed to get float data");
806 return {};
807 }
808 m_dst_offs += *elem_size;
809 }
810 return BuildValueObject();
811 }
812
813 // case 3: get from GPRs
814
815 // first, check if this is a packed struct or not
816 auto ast = m_type.GetTypeSystem().dyn_cast_or_null<TypeSystemClang>();
817 if (ast) {
818 clang::RecordDecl *record_decl = TypeSystemClang::GetAsRecordDecl(m_type);
819
820 if (record_decl) {
821 auto attrs = record_decl->attrs();
822 for (const auto &attr : attrs) {
823 if (attr->getKind() == clang::attr::Packed) {
824 m_packed = true;
825 break;
826 }
827 }
828 }
829 }
830
831 LLDB_LOG(m_log, LOG_PREFIX "{0} struct",
832 m_packed ? "packed" : "not packed");
833
834 for (uint32_t i = 0; i < n; i++) {
835 std::string name;
836 uint32_t size;
837 (void)GetChildType(i, name, size);
838 // NOTE: the offset returned by GetChildCompilerTypeAtIndex()
839 // can't be used because it never considers alignment bytes
840 // between struct fields.
841 LLDB_LOG(m_log, LOG_PREFIX "field={0}, size={1}", name, size);
842 if (!ExtractField(size))
843 return ValueObjectSP();
844 }
845
846 return BuildValueObject();
847 }
848
849 // extract 'size' bytes at 'offs' from GPRs
ExtractFromRegs(int32_t offs,uint32_t size,void * buf)850 bool ExtractFromRegs(int32_t offs, uint32_t size, void *buf) {
851 while (size) {
852 auto reg = GetGPRByOffs(offs);
853 if (!reg.IsValid())
854 return false;
855
856 uint32_t n = std::min(reg.Avail(), size);
857 uint64_t raw_data;
858
859 if (!reg.GetRawData(raw_data))
860 return false;
861
862 memcpy(buf, (char *)&raw_data + reg.Offs(), n);
863 offs += n;
864 size -= n;
865 buf = (char *)buf + n;
866 }
867 return true;
868 }
869
870 // extract one field from GPRs and put it in our buffer
ExtractField(uint32_t size)871 bool ExtractField(uint32_t size) {
872 auto reg = GetGPRByOffs(m_src_offs);
873 if (!reg.IsValid())
874 return false;
875
876 // handle padding
877 if (!m_packed) {
878 uint32_t n = m_src_offs % size;
879
880 // not 'size' bytes aligned
881 if (n) {
882 LLDB_LOG(m_log,
883 LOG_PREFIX "Extracting {0} alignment bytes at offset {1}", n,
884 m_src_offs);
885 // get alignment bytes
886 if (!ExtractFromRegs(m_src_offs, n, m_data_up->GetBytes() + m_dst_offs))
887 return false;
888 m_src_offs += n;
889 m_dst_offs += n;
890 }
891 }
892
893 // get field
894 LLDB_LOG(m_log, LOG_PREFIX "Extracting {0} field bytes at offset {1}", size,
895 m_src_offs);
896 if (!ExtractFromRegs(m_src_offs, size, m_data_up->GetBytes() + m_dst_offs))
897 return false;
898 m_src_offs += size;
899 m_dst_offs += size;
900 return true;
901 }
902
903 // get child
GetChildType(uint32_t i,std::string & name,uint32_t & size)904 llvm::Expected<CompilerType> GetChildType(uint32_t i, std::string &name,
905 uint32_t &size) {
906 // GetChild constant inputs
907 const bool transparent_pointers = false;
908 const bool omit_empty_base_classes = true;
909 const bool ignore_array_bounds = false;
910 // GetChild output params
911 int32_t child_offs;
912 uint32_t child_bitfield_bit_size;
913 uint32_t child_bitfield_bit_offset;
914 bool child_is_base_class;
915 bool child_is_deref_of_parent;
916 ValueObject *valobj = nullptr;
917 uint64_t language_flags;
918 ExecutionContext exe_ctx;
919 m_thread.CalculateExecutionContext(exe_ctx);
920
921 return m_type.GetChildCompilerTypeAtIndex(
922 &exe_ctx, i, transparent_pointers, omit_empty_base_classes,
923 ignore_array_bounds, name, size, child_offs, child_bitfield_bit_size,
924 child_bitfield_bit_offset, child_is_base_class,
925 child_is_deref_of_parent, valobj, language_flags);
926 }
927 };
928
929 #undef LOG_PREFIX
930
931 } // anonymous namespace
932
933 ValueObjectSP
GetReturnValueObjectSimple(Thread & thread,CompilerType & type) const934 ABISysV_ppc64::GetReturnValueObjectSimple(Thread &thread,
935 CompilerType &type) const {
936 if (!type)
937 return ValueObjectSP();
938
939 auto exp_extractor = ReturnValueExtractor::Create(thread, type);
940 if (!exp_extractor) {
941 Log *log = GetLog(LLDBLog::Expressions);
942 LLDB_LOG_ERROR(log, exp_extractor.takeError(),
943 "Extracting return value failed: {0}");
944 return ValueObjectSP();
945 }
946
947 return exp_extractor.get().GetValue();
948 }
949
GetReturnValueObjectImpl(Thread & thread,CompilerType & return_compiler_type) const950 ValueObjectSP ABISysV_ppc64::GetReturnValueObjectImpl(
951 Thread &thread, CompilerType &return_compiler_type) const {
952 return GetReturnValueObjectSimple(thread, return_compiler_type);
953 }
954
CreateFunctionEntryUnwindPlan(UnwindPlan & unwind_plan)955 bool ABISysV_ppc64::CreateFunctionEntryUnwindPlan(UnwindPlan &unwind_plan) {
956 unwind_plan.Clear();
957 unwind_plan.SetRegisterKind(eRegisterKindDWARF);
958
959 uint32_t lr_reg_num;
960 uint32_t sp_reg_num;
961 uint32_t pc_reg_num;
962
963 if (GetByteOrder() == lldb::eByteOrderLittle) {
964 lr_reg_num = ppc64le_dwarf::dwarf_lr_ppc64le;
965 sp_reg_num = ppc64le_dwarf::dwarf_r1_ppc64le;
966 pc_reg_num = ppc64le_dwarf::dwarf_pc_ppc64le;
967 } else {
968 lr_reg_num = ppc64_dwarf::dwarf_lr_ppc64;
969 sp_reg_num = ppc64_dwarf::dwarf_r1_ppc64;
970 pc_reg_num = ppc64_dwarf::dwarf_pc_ppc64;
971 }
972
973 UnwindPlan::RowSP row(new UnwindPlan::Row);
974
975 // Our Call Frame Address is the stack pointer value
976 row->GetCFAValue().SetIsRegisterPlusOffset(sp_reg_num, 0);
977
978 // The previous PC is in the LR
979 row->SetRegisterLocationToRegister(pc_reg_num, lr_reg_num, true);
980 unwind_plan.AppendRow(row);
981
982 // All other registers are the same.
983
984 unwind_plan.SetSourceName("ppc64 at-func-entry default");
985 unwind_plan.SetSourcedFromCompiler(eLazyBoolNo);
986
987 return true;
988 }
989
CreateDefaultUnwindPlan(UnwindPlan & unwind_plan)990 bool ABISysV_ppc64::CreateDefaultUnwindPlan(UnwindPlan &unwind_plan) {
991 unwind_plan.Clear();
992 unwind_plan.SetRegisterKind(eRegisterKindDWARF);
993
994 uint32_t sp_reg_num;
995 uint32_t pc_reg_num;
996 uint32_t cr_reg_num;
997
998 if (GetByteOrder() == lldb::eByteOrderLittle) {
999 sp_reg_num = ppc64le_dwarf::dwarf_r1_ppc64le;
1000 pc_reg_num = ppc64le_dwarf::dwarf_lr_ppc64le;
1001 cr_reg_num = ppc64le_dwarf::dwarf_cr_ppc64le;
1002 } else {
1003 sp_reg_num = ppc64_dwarf::dwarf_r1_ppc64;
1004 pc_reg_num = ppc64_dwarf::dwarf_lr_ppc64;
1005 cr_reg_num = ppc64_dwarf::dwarf_cr_ppc64;
1006 }
1007
1008 UnwindPlan::RowSP row(new UnwindPlan::Row);
1009 const int32_t ptr_size = 8;
1010 row->SetUnspecifiedRegistersAreUndefined(true);
1011 row->GetCFAValue().SetIsRegisterDereferenced(sp_reg_num);
1012
1013 row->SetRegisterLocationToAtCFAPlusOffset(pc_reg_num, ptr_size * 2, true);
1014 row->SetRegisterLocationToIsCFAPlusOffset(sp_reg_num, 0, true);
1015 row->SetRegisterLocationToAtCFAPlusOffset(cr_reg_num, ptr_size, true);
1016
1017 unwind_plan.AppendRow(row);
1018 unwind_plan.SetSourceName("ppc64 default unwind plan");
1019 unwind_plan.SetSourcedFromCompiler(eLazyBoolNo);
1020 unwind_plan.SetUnwindPlanValidAtAllInstructions(eLazyBoolNo);
1021 unwind_plan.SetUnwindPlanForSignalTrap(eLazyBoolNo);
1022 unwind_plan.SetReturnAddressRegister(pc_reg_num);
1023 return true;
1024 }
1025
RegisterIsVolatile(const RegisterInfo * reg_info)1026 bool ABISysV_ppc64::RegisterIsVolatile(const RegisterInfo *reg_info) {
1027 return !RegisterIsCalleeSaved(reg_info);
1028 }
1029
1030 // See "Register Usage" in the
1031 // "System V Application Binary Interface"
1032 // "64-bit PowerPC ELF Application Binary Interface Supplement" current version
1033 // is 2 released 2015 at
1034 // https://members.openpowerfoundation.org/document/dl/576
RegisterIsCalleeSaved(const RegisterInfo * reg_info)1035 bool ABISysV_ppc64::RegisterIsCalleeSaved(const RegisterInfo *reg_info) {
1036 if (reg_info) {
1037 // Preserved registers are :
1038 // r1,r2,r13-r31
1039 // cr2-cr4 (partially preserved)
1040 // f14-f31 (not yet)
1041 // v20-v31 (not yet)
1042 // vrsave (not yet)
1043
1044 const char *name = reg_info->name;
1045 if (name[0] == 'r') {
1046 if ((name[1] == '1' || name[1] == '2') && name[2] == '\0')
1047 return true;
1048 if (name[1] == '1' && name[2] > '2')
1049 return true;
1050 if ((name[1] == '2' || name[1] == '3') && name[2] != '\0')
1051 return true;
1052 }
1053
1054 if (name[0] == 'f' && name[1] >= '0' && name[2] <= '9') {
1055 if (name[2] == '\0')
1056 return false;
1057 if (name[1] == '1' && name[2] >= '4')
1058 return true;
1059 if ((name[1] == '2' || name[1] == '3') && name[2] != '\0')
1060 return true;
1061 }
1062
1063 if (name[0] == 's' && name[1] == 'p' && name[2] == '\0') // sp
1064 return true;
1065 if (name[0] == 'f' && name[1] == 'p' && name[2] == '\0') // fp
1066 return false;
1067 if (name[0] == 'p' && name[1] == 'c' && name[2] == '\0') // pc
1068 return true;
1069 }
1070 return false;
1071 }
1072
Initialize()1073 void ABISysV_ppc64::Initialize() {
1074 PluginManager::RegisterPlugin(
1075 GetPluginNameStatic(), "System V ABI for ppc64 targets", CreateInstance);
1076 }
1077
Terminate()1078 void ABISysV_ppc64::Terminate() {
1079 PluginManager::UnregisterPlugin(CreateInstance);
1080 }
1081