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
49using namespace lldb;
50using namespace lldb_private;
51
52LLDB_PLUGIN_DEFINE(ABISysV_ppc64)
53
54const lldb_private::RegisterInfo *
55ABISysV_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
65size_t ABISysV_ppc64::GetRedZoneSize() const { return 224; }
66
67lldb::ByteOrder ABISysV_ppc64::GetByteOrder() const {
68 return GetProcessSP()->GetByteOrder();
69}
70
71// Static Functions
72
73ABISP
74ABISysV_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
82bool 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(mask: LLDBLog::Expressions);
86
87 if (log) {
88 StreamString s;
89 s.Printf(format: "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(format: ", arg%" PRIu64 " = 0x%" PRIx64, static_cast<uint64_t>(i + 1),
97 args[i]);
98 s.PutCString(cstr: ")");
99 log->PutString(str: 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(reg_kind: 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, uval: 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(reg_kind: eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC);
133 const RegisterInfo *sp_reg_info =
134 reg_ctx->GetRegisterInfo(reg_kind: eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP);
135 ProcessSP process_sp(thread.GetProcess());
136 const RegisterInfo *lr_reg_info =
137 reg_ctx->GetRegisterInfo(reg_kind: eRegisterKindGeneric, LLDB_REGNUM_GENERIC_RA);
138 const RegisterInfo *r2_reg_info = reg_ctx->GetRegisterInfoAtIndex(reg: 2);
139 const RegisterInfo *r12_reg_info = reg_ctx->GetRegisterInfoAtIndex(reg: 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(vm_addr: sp + 16, ptr_value: 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(reg_info: lr_reg_info, uval: 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(reg_info: r12_reg_info, uval: func_addr))
157 return false;
158
159 // Read TOC pointer value.
160 reg_value = reg_ctx->ReadRegisterAsUnsigned(reg_info: r2_reg_info, fail_value: 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(vm_addr: sp + stack_offset, ptr_value: reg_value, error))
173 return false;
174
175 // Read the current SP value.
176 reg_value = reg_ctx->ReadRegisterAsUnsigned(reg_info: sp_reg_info, fail_value: 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(vm_addr: sp, ptr_value: 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(reg_info: sp_reg_info, uval: 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(reg_info: pc_reg_info, uval: func_addr))
195 return false;
196
197 return true;
198}
199
200static bool ReadIntegerArgument(Scalar &scalar, unsigned int bit_width,
201 bool is_signed, Thread &thread,
202 uint32_t *argument_register_ids,
203 unsigned int &current_argument_register,
204 addr_t &current_stack_argument) {
205 if (bit_width > 64)
206 return false; // Scalar can't hold large integer arguments
207
208 if (current_argument_register < 6) {
209 scalar = thread.GetRegisterContext()->ReadRegisterAsUnsigned(
210 reg: argument_register_ids[current_argument_register], fail_value: 0);
211 current_argument_register++;
212 if (is_signed)
213 scalar.SignExtend(bit_pos: bit_width);
214 } else {
215 uint32_t byte_size = (bit_width + (8 - 1)) / 8;
216 Status error;
217 if (thread.GetProcess()->ReadScalarIntegerFromMemory(
218 addr: 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
227bool 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(fail_value: 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(reg_kind: 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(idx: 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(exe_scope: &thread);
276 if (!bit_size)
277 return false;
278 bool is_signed;
279
280 if (compiler_type.IsIntegerOrEnumerationType(is_signed)) {
281 ReadIntegerArgument(scalar&: value->GetScalar(), bit_width: *bit_size, is_signed, thread,
282 argument_register_ids, current_argument_register,
283 current_stack_argument);
284 } else if (compiler_type.IsPointerType()) {
285 ReadIntegerArgument(scalar&: value->GetScalar(), bit_width: *bit_size, is_signed: false, thread,
286 argument_register_ids, current_argument_register,
287 current_stack_argument);
288 }
289 }
290
291 return true;
292}
293
294Status 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(reg_name: "r3", start_idx: 0);
320
321 DataExtractor data;
322 Status data_error;
323 size_t num_bytes = new_value_sp->GetData(data, error&: 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_ptr: &offset, byte_size: num_bytes);
333
334 if (reg_ctx->WriteRegisterFromUnsigned(reg_info, uval: 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(exe_scope: 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, error&: 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(src_offset: 0, src_len: num_bytes, dst: buffer, dst_len: 16, dst_byte_order: 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
390namespace {
391
392#define LOG_PREFIX "ReturnValueExtractor: "
393
394class ReturnValueExtractor {
395 // This class represents a register, from which data may be extracted.
396 //
397 // It may be constructed by directly specifying its index (where 0 is the
398 // first register used to return values) or by specifying the offset of a
399 // given struct field, in which case the appropriated register index will be
400 // calculated.
401 class Register {
402 public:
403 enum Type {
404 GPR, // General Purpose Register
405 FPR // Floating Point Register
406 };
407
408 // main constructor
409 //
410 // offs - field offset in struct
411 Register(Type ty, uint32_t index, uint32_t offs, RegisterContext *reg_ctx,
412 ByteOrder byte_order)
413 : m_index(index), m_offs(offs % sizeof(uint64_t)),
414 m_avail(sizeof(uint64_t) - m_offs), m_type(ty), m_reg_ctx(reg_ctx),
415 m_byte_order(byte_order) {}
416
417 // explicit index, no offset
418 Register(Type ty, uint32_t index, RegisterContext *reg_ctx,
419 ByteOrder byte_order)
420 : Register(ty, index, 0, reg_ctx, byte_order) {}
421
422 // GPR, calculate index from offs
423 Register(uint32_t offs, RegisterContext *reg_ctx, ByteOrder byte_order)
424 : Register(GPR, offs / sizeof(uint64_t), offs, reg_ctx, byte_order) {}
425
426 uint32_t Index() const { return m_index; }
427
428 // register offset where data is located
429 uint32_t Offs() const { return m_offs; }
430
431 // available bytes in this register
432 uint32_t Avail() const { return m_avail; }
433
434 bool IsValid() const {
435 if (m_index > 7) {
436 LLDB_LOG(m_log, LOG_PREFIX
437 "No more than 8 registers should be used to return values");
438 return false;
439 }
440 return true;
441 }
442
443 std::string GetName() const {
444 if (m_type == GPR)
445 return ("r" + llvm::Twine(m_index + 3)).str();
446 else
447 return ("f" + llvm::Twine(m_index + 1)).str();
448 }
449
450 // get raw register data
451 bool GetRawData(uint64_t &raw_data) {
452 const RegisterInfo *reg_info =
453 m_reg_ctx->GetRegisterInfoByName(reg_name: 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_value&: 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: *reg_info, dst: &raw_data, dst_len: sizeof(raw_data), dst_byte_order: 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(mask: LLDBLog::Expressions);
484 };
485
486 Register GetGPR(uint32_t index) const {
487 return Register(Register::GPR, index, m_reg_ctx, m_byte_order);
488 }
489
490 Register GetFPR(uint32_t index) const {
491 return Register(Register::FPR, index, m_reg_ctx, m_byte_order);
492 }
493
494 Register GetGPRByOffs(uint32_t offs) const {
495 return Register(offs, m_reg_ctx, m_byte_order);
496 }
497
498public:
499 // factory
500 static llvm::Expected<ReturnValueExtractor> Create(Thread &thread,
501 CompilerType &type) {
502 RegisterContext *reg_ctx = thread.GetRegisterContext().get();
503 if (!reg_ctx)
504 return llvm::make_error<llvm::StringError>(
505 LOG_PREFIX "Failed to get RegisterContext",
506 Args: llvm::inconvertibleErrorCode());
507
508 ProcessSP process_sp = thread.GetProcess();
509 if (!process_sp)
510 return llvm::make_error<llvm::StringError>(
511 LOG_PREFIX "GetProcess() failed", Args: llvm::inconvertibleErrorCode());
512
513 return ReturnValueExtractor(thread, type, reg_ctx, process_sp);
514 }
515
516 // main method: get value of the type specified at construction time
517 ValueObjectSP GetValue() {
518 const uint32_t type_flags = m_type.GetTypeInfo();
519
520 // call the appropriate type handler
521 ValueSP value_sp;
522 ValueObjectSP valobj_sp;
523 if (type_flags & eTypeIsScalar) {
524 if (type_flags & eTypeIsInteger) {
525 value_sp = GetIntegerValue(reg_index: 0);
526 } else if (type_flags & eTypeIsFloat) {
527 if (type_flags & eTypeIsComplex) {
528 LLDB_LOG(m_log, LOG_PREFIX "Complex numbers are not supported yet");
529 return ValueObjectSP();
530 } else {
531 value_sp = GetFloatValue(type&: m_type, reg_index: 0);
532 }
533 }
534 } else if (type_flags & eTypeIsPointer) {
535 value_sp = GetPointerValue(reg_index: 0);
536 }
537
538 if (value_sp) {
539 valobj_sp = ValueObjectConstResult::Create(
540 exe_scope: m_thread.GetStackFrameAtIndex(idx: 0).get(), value&: *value_sp, name: ConstString(""));
541 } else if (type_flags & eTypeIsVector) {
542 valobj_sp = GetVectorValueObject();
543 } else if (type_flags & eTypeIsStructUnion || type_flags & eTypeIsClass) {
544 valobj_sp = GetStructValueObject();
545 }
546
547 return valobj_sp;
548 }
549
550private:
551 // data
552 Thread &m_thread;
553 CompilerType &m_type;
554 uint64_t m_byte_size;
555 std::unique_ptr<DataBufferHeap> m_data_up;
556 int32_t m_src_offs = 0;
557 int32_t m_dst_offs = 0;
558 bool m_packed = false;
559 Log *m_log = GetLog(mask: LLDBLog::Expressions);
560 RegisterContext *m_reg_ctx;
561 ProcessSP m_process_sp;
562 ByteOrder m_byte_order;
563 uint32_t m_addr_size;
564
565 // methods
566
567 // constructor
568 ReturnValueExtractor(Thread &thread, CompilerType &type,
569 RegisterContext *reg_ctx, ProcessSP process_sp)
570 : m_thread(thread), m_type(type),
571 m_byte_size(m_type.GetByteSize(exe_scope: &thread).value_or(u: 0)),
572 m_data_up(new DataBufferHeap(m_byte_size, 0)), m_reg_ctx(reg_ctx),
573 m_process_sp(process_sp), m_byte_order(process_sp->GetByteOrder()),
574 m_addr_size(
575 process_sp->GetTarget().GetArchitecture().GetAddressByteSize()) {}
576
577 // build a new scalar value
578 ValueSP NewScalarValue(CompilerType &type) {
579 ValueSP value_sp(new Value);
580 value_sp->SetCompilerType(type);
581 value_sp->SetValueType(Value::ValueType::Scalar);
582 return value_sp;
583 }
584
585 // get an integer value in the specified register
586 ValueSP GetIntegerValue(uint32_t reg_index) {
587 uint64_t raw_value;
588 auto reg = GetGPR(index: reg_index);
589 if (!reg.GetRawData(raw_data&: raw_value))
590 return ValueSP();
591
592 // build value from data
593 ValueSP value_sp(NewScalarValue(type&: m_type));
594
595 uint32_t type_flags = m_type.GetTypeInfo();
596 bool is_signed = (type_flags & eTypeIsSigned) != 0;
597
598 switch (m_byte_size) {
599 case sizeof(uint64_t):
600 if (is_signed)
601 value_sp->GetScalar() = (int64_t)(raw_value);
602 else
603 value_sp->GetScalar() = (uint64_t)(raw_value);
604 break;
605
606 case sizeof(uint32_t):
607 if (is_signed)
608 value_sp->GetScalar() = (int32_t)(raw_value & UINT32_MAX);
609 else
610 value_sp->GetScalar() = (uint32_t)(raw_value & UINT32_MAX);
611 break;
612
613 case sizeof(uint16_t):
614 if (is_signed)
615 value_sp->GetScalar() = (int16_t)(raw_value & UINT16_MAX);
616 else
617 value_sp->GetScalar() = (uint16_t)(raw_value & UINT16_MAX);
618 break;
619
620 case sizeof(uint8_t):
621 if (is_signed)
622 value_sp->GetScalar() = (int8_t)(raw_value & UINT8_MAX);
623 else
624 value_sp->GetScalar() = (uint8_t)(raw_value & UINT8_MAX);
625 break;
626
627 default:
628 llvm_unreachable("Invalid integer size");
629 }
630
631 return value_sp;
632 }
633
634 // get a floating point value on the specified register
635 ValueSP GetFloatValue(CompilerType &type, uint32_t reg_index) {
636 uint64_t raw_data;
637 auto reg = GetFPR(index: reg_index);
638 if (!reg.GetRawData(raw_data))
639 return {};
640
641 // build value from data
642 ValueSP value_sp(NewScalarValue(type));
643
644 DataExtractor de(&raw_data, sizeof(raw_data), m_byte_order, m_addr_size);
645
646 offset_t offset = 0;
647 std::optional<uint64_t> byte_size = type.GetByteSize(exe_scope: m_process_sp.get());
648 if (!byte_size)
649 return {};
650 switch (*byte_size) {
651 case sizeof(float):
652 value_sp->GetScalar() = (float)de.GetDouble(offset_ptr: &offset);
653 break;
654
655 case sizeof(double):
656 value_sp->GetScalar() = de.GetDouble(offset_ptr: &offset);
657 break;
658
659 default:
660 llvm_unreachable("Invalid floating point size");
661 }
662
663 return value_sp;
664 }
665
666 // get pointer value from register
667 ValueSP GetPointerValue(uint32_t reg_index) {
668 uint64_t raw_data;
669 auto reg = GetGPR(index: reg_index);
670 if (!reg.GetRawData(raw_data))
671 return ValueSP();
672
673 // build value from raw data
674 ValueSP value_sp(NewScalarValue(type&: m_type));
675 value_sp->GetScalar() = raw_data;
676 return value_sp;
677 }
678
679 // build the ValueObject from our data buffer
680 ValueObjectSP BuildValueObject() {
681 DataExtractor de(DataBufferSP(m_data_up.release()), m_byte_order,
682 m_addr_size);
683 return ValueObjectConstResult::Create(exe_scope: &m_thread, compiler_type: m_type, name: ConstString(""),
684 data: de);
685 }
686
687 // get a vector return value
688 ValueObjectSP GetVectorValueObject() {
689 const uint32_t MAX_VRS = 2;
690
691 // get first V register used to return values
692 const RegisterInfo *vr[MAX_VRS];
693 vr[0] = m_reg_ctx->GetRegisterInfoByName(reg_name: "vr2");
694 if (!vr[0]) {
695 LLDB_LOG(m_log, LOG_PREFIX "Failed to get vr2 RegisterInfo");
696 return ValueObjectSP();
697 }
698
699 const uint32_t vr_size = vr[0]->byte_size;
700 size_t vrs = 1;
701 if (m_byte_size > 2 * vr_size) {
702 LLDB_LOG(
703 m_log, LOG_PREFIX
704 "Returning vectors that don't fit in 2 VR regs is not supported");
705 return ValueObjectSP();
706 }
707
708 // load vr3, if needed
709 if (m_byte_size > vr_size) {
710 vrs++;
711 vr[1] = m_reg_ctx->GetRegisterInfoByName(reg_name: "vr3");
712 if (!vr[1]) {
713 LLDB_LOG(m_log, LOG_PREFIX "Failed to get vr3 RegisterInfo");
714 return ValueObjectSP();
715 }
716 }
717
718 // Get the whole contents of vector registers and let the logic here
719 // arrange the data properly.
720
721 RegisterValue vr_val[MAX_VRS];
722 Status error;
723 std::unique_ptr<DataBufferHeap> vr_data(
724 new DataBufferHeap(vrs * vr_size, 0));
725
726 for (uint32_t i = 0; i < vrs; i++) {
727 if (!m_reg_ctx->ReadRegister(reg_info: vr[i], reg_value&: vr_val[i])) {
728 LLDB_LOG(m_log, LOG_PREFIX "Failed to read vector register contents");
729 return ValueObjectSP();
730 }
731 if (!vr_val[i].GetAsMemoryData(reg_info: *vr[i], dst: vr_data->GetBytes() + i * vr_size,
732 dst_len: vr_size, dst_byte_order: m_byte_order, error)) {
733 LLDB_LOG(m_log, LOG_PREFIX "Failed to extract vector register bytes");
734 return ValueObjectSP();
735 }
736 }
737
738 // The compiler generated code seems to always put the vector elements at
739 // the end of the vector register, in case they don't occupy all of it.
740 // This offset variable handles this.
741 uint32_t offs = 0;
742 if (m_byte_size < vr_size)
743 offs = vr_size - m_byte_size;
744
745 // copy extracted data to our buffer
746 memcpy(dest: m_data_up->GetBytes(), src: vr_data->GetBytes() + offs, n: m_byte_size);
747 return BuildValueObject();
748 }
749
750 // get a struct return value
751 ValueObjectSP GetStructValueObject() {
752 // case 1: get from stack
753 if (m_byte_size > 2 * sizeof(uint64_t)) {
754 uint64_t addr;
755 auto reg = GetGPR(index: 0);
756 if (!reg.GetRawData(raw_data&: addr))
757 return {};
758
759 Status error;
760 size_t rc = m_process_sp->ReadMemory(vm_addr: addr, buf: m_data_up->GetBytes(),
761 size: m_byte_size, error);
762 if (rc != m_byte_size) {
763 LLDB_LOG(m_log, LOG_PREFIX "Failed to read memory pointed by r3");
764 return ValueObjectSP();
765 }
766 return BuildValueObject();
767 }
768
769 // get number of children
770 const bool omit_empty_base_classes = true;
771 auto n_or_err = m_type.GetNumChildren(omit_empty_base_classes, exe_ctx: nullptr);
772 if (!n_or_err) {
773 LLDB_LOG_ERROR(m_log, n_or_err.takeError(), LOG_PREFIX "{0}");
774 return {};
775 }
776 uint32_t n = *n_or_err;
777 if (!n) {
778 LLDB_LOG(m_log, LOG_PREFIX "No children found in struct");
779 return {};
780 }
781
782 // case 2: homogeneous double or float aggregate
783 CompilerType elem_type;
784 if (m_type.IsHomogeneousAggregate(base_type_ptr: &elem_type)) {
785 uint32_t type_flags = elem_type.GetTypeInfo();
786 std::optional<uint64_t> elem_size =
787 elem_type.GetByteSize(exe_scope: m_process_sp.get());
788 if (!elem_size)
789 return {};
790 if (type_flags & eTypeIsComplex || !(type_flags & eTypeIsFloat)) {
791 LLDB_LOG(m_log,
792 LOG_PREFIX "Unexpected type found in homogeneous aggregate");
793 return {};
794 }
795
796 for (uint32_t i = 0; i < n; i++) {
797 ValueSP val_sp = GetFloatValue(type&: elem_type, reg_index: i);
798 if (!val_sp)
799 return {};
800
801 // copy to buffer
802 Status error;
803 size_t rc = val_sp->GetScalar().GetAsMemoryData(
804 dst: m_data_up->GetBytes() + m_dst_offs, dst_len: *elem_size, dst_byte_order: m_byte_order,
805 error);
806 if (rc != *elem_size) {
807 LLDB_LOG(m_log, LOG_PREFIX "Failed to get float data");
808 return {};
809 }
810 m_dst_offs += *elem_size;
811 }
812 return BuildValueObject();
813 }
814
815 // case 3: get from GPRs
816
817 // first, check if this is a packed struct or not
818 auto ast = m_type.GetTypeSystem().dyn_cast_or_null<TypeSystemClang>();
819 if (ast) {
820 clang::RecordDecl *record_decl = TypeSystemClang::GetAsRecordDecl(type: m_type);
821
822 if (record_decl) {
823 auto attrs = record_decl->attrs();
824 for (const auto &attr : attrs) {
825 if (attr->getKind() == clang::attr::Packed) {
826 m_packed = true;
827 break;
828 }
829 }
830 }
831 }
832
833 LLDB_LOG(m_log, LOG_PREFIX "{0} struct",
834 m_packed ? "packed" : "not packed");
835
836 for (uint32_t i = 0; i < n; i++) {
837 std::string name;
838 uint32_t size;
839 GetChildType(i, name, size);
840 // NOTE: the offset returned by GetChildCompilerTypeAtIndex()
841 // can't be used because it never considers alignment bytes
842 // between struct fields.
843 LLDB_LOG(m_log, LOG_PREFIX "field={0}, size={1}", name, size);
844 if (!ExtractField(size))
845 return ValueObjectSP();
846 }
847
848 return BuildValueObject();
849 }
850
851 // extract 'size' bytes at 'offs' from GPRs
852 bool ExtractFromRegs(int32_t offs, uint32_t size, void *buf) {
853 while (size) {
854 auto reg = GetGPRByOffs(offs);
855 if (!reg.IsValid())
856 return false;
857
858 uint32_t n = std::min(a: reg.Avail(), b: size);
859 uint64_t raw_data;
860
861 if (!reg.GetRawData(raw_data))
862 return false;
863
864 memcpy(dest: buf, src: (char *)&raw_data + reg.Offs(), n: n);
865 offs += n;
866 size -= n;
867 buf = (char *)buf + n;
868 }
869 return true;
870 }
871
872 // extract one field from GPRs and put it in our buffer
873 bool ExtractField(uint32_t size) {
874 auto reg = GetGPRByOffs(offs: m_src_offs);
875 if (!reg.IsValid())
876 return false;
877
878 // handle padding
879 if (!m_packed) {
880 uint32_t n = m_src_offs % size;
881
882 // not 'size' bytes aligned
883 if (n) {
884 LLDB_LOG(m_log,
885 LOG_PREFIX "Extracting {0} alignment bytes at offset {1}", n,
886 m_src_offs);
887 // get alignment bytes
888 if (!ExtractFromRegs(offs: m_src_offs, size: n, buf: m_data_up->GetBytes() + m_dst_offs))
889 return false;
890 m_src_offs += n;
891 m_dst_offs += n;
892 }
893 }
894
895 // get field
896 LLDB_LOG(m_log, LOG_PREFIX "Extracting {0} field bytes at offset {1}", size,
897 m_src_offs);
898 if (!ExtractFromRegs(offs: m_src_offs, size, buf: m_data_up->GetBytes() + m_dst_offs))
899 return false;
900 m_src_offs += size;
901 m_dst_offs += size;
902 return true;
903 }
904
905 // get child
906 CompilerType GetChildType(uint32_t i, std::string &name, uint32_t &size) {
907 // GetChild constant inputs
908 const bool transparent_pointers = false;
909 const bool omit_empty_base_classes = true;
910 const bool ignore_array_bounds = false;
911 // GetChild output params
912 int32_t child_offs;
913 uint32_t child_bitfield_bit_size;
914 uint32_t child_bitfield_bit_offset;
915 bool child_is_base_class;
916 bool child_is_deref_of_parent;
917 ValueObject *valobj = nullptr;
918 uint64_t language_flags;
919 ExecutionContext exe_ctx;
920 m_thread.CalculateExecutionContext(exe_ctx);
921
922 return m_type.GetChildCompilerTypeAtIndex(
923 exe_ctx: &exe_ctx, idx: i, transparent_pointers, omit_empty_base_classes,
924 ignore_array_bounds, child_name&: name, child_byte_size&: size, child_byte_offset&: child_offs, child_bitfield_bit_size,
925 child_bitfield_bit_offset, child_is_base_class,
926 child_is_deref_of_parent, valobj, language_flags);
927 }
928};
929
930#undef LOG_PREFIX
931
932} // anonymous namespace
933
934ValueObjectSP
935ABISysV_ppc64::GetReturnValueObjectSimple(Thread &thread,
936 CompilerType &type) const {
937 if (!type)
938 return ValueObjectSP();
939
940 auto exp_extractor = ReturnValueExtractor::Create(thread, type);
941 if (!exp_extractor) {
942 Log *log = GetLog(mask: LLDBLog::Expressions);
943 LLDB_LOG_ERROR(log, exp_extractor.takeError(),
944 "Extracting return value failed: {0}");
945 return ValueObjectSP();
946 }
947
948 return exp_extractor.get().GetValue();
949}
950
951ValueObjectSP ABISysV_ppc64::GetReturnValueObjectImpl(
952 Thread &thread, CompilerType &return_compiler_type) const {
953 return GetReturnValueObjectSimple(thread, type&: return_compiler_type);
954}
955
956bool ABISysV_ppc64::CreateFunctionEntryUnwindPlan(UnwindPlan &unwind_plan) {
957 unwind_plan.Clear();
958 unwind_plan.SetRegisterKind(eRegisterKindDWARF);
959
960 uint32_t lr_reg_num;
961 uint32_t sp_reg_num;
962 uint32_t pc_reg_num;
963
964 if (GetByteOrder() == lldb::eByteOrderLittle) {
965 lr_reg_num = ppc64le_dwarf::dwarf_lr_ppc64le;
966 sp_reg_num = ppc64le_dwarf::dwarf_r1_ppc64le;
967 pc_reg_num = ppc64le_dwarf::dwarf_pc_ppc64le;
968 } else {
969 lr_reg_num = ppc64_dwarf::dwarf_lr_ppc64;
970 sp_reg_num = ppc64_dwarf::dwarf_r1_ppc64;
971 pc_reg_num = ppc64_dwarf::dwarf_pc_ppc64;
972 }
973
974 UnwindPlan::RowSP row(new UnwindPlan::Row);
975
976 // Our Call Frame Address is the stack pointer value
977 row->GetCFAValue().SetIsRegisterPlusOffset(reg_num: sp_reg_num, offset: 0);
978
979 // The previous PC is in the LR
980 row->SetRegisterLocationToRegister(reg_num: pc_reg_num, other_reg_num: lr_reg_num, can_replace: true);
981 unwind_plan.AppendRow(row_sp: row);
982
983 // All other registers are the same.
984
985 unwind_plan.SetSourceName("ppc64 at-func-entry default");
986 unwind_plan.SetSourcedFromCompiler(eLazyBoolNo);
987
988 return true;
989}
990
991bool ABISysV_ppc64::CreateDefaultUnwindPlan(UnwindPlan &unwind_plan) {
992 unwind_plan.Clear();
993 unwind_plan.SetRegisterKind(eRegisterKindDWARF);
994
995 uint32_t sp_reg_num;
996 uint32_t pc_reg_num;
997 uint32_t cr_reg_num;
998
999 if (GetByteOrder() == lldb::eByteOrderLittle) {
1000 sp_reg_num = ppc64le_dwarf::dwarf_r1_ppc64le;
1001 pc_reg_num = ppc64le_dwarf::dwarf_lr_ppc64le;
1002 cr_reg_num = ppc64le_dwarf::dwarf_cr_ppc64le;
1003 } else {
1004 sp_reg_num = ppc64_dwarf::dwarf_r1_ppc64;
1005 pc_reg_num = ppc64_dwarf::dwarf_lr_ppc64;
1006 cr_reg_num = ppc64_dwarf::dwarf_cr_ppc64;
1007 }
1008
1009 UnwindPlan::RowSP row(new UnwindPlan::Row);
1010 const int32_t ptr_size = 8;
1011 row->SetUnspecifiedRegistersAreUndefined(true);
1012 row->GetCFAValue().SetIsRegisterDereferenced(sp_reg_num);
1013
1014 row->SetRegisterLocationToAtCFAPlusOffset(reg_num: pc_reg_num, offset: ptr_size * 2, can_replace: true);
1015 row->SetRegisterLocationToIsCFAPlusOffset(reg_num: sp_reg_num, offset: 0, can_replace: true);
1016 row->SetRegisterLocationToAtCFAPlusOffset(reg_num: cr_reg_num, offset: ptr_size, can_replace: true);
1017
1018 unwind_plan.AppendRow(row_sp: row);
1019 unwind_plan.SetSourceName("ppc64 default unwind plan");
1020 unwind_plan.SetSourcedFromCompiler(eLazyBoolNo);
1021 unwind_plan.SetUnwindPlanValidAtAllInstructions(eLazyBoolNo);
1022 unwind_plan.SetUnwindPlanForSignalTrap(eLazyBoolNo);
1023 unwind_plan.SetReturnAddressRegister(pc_reg_num);
1024 return true;
1025}
1026
1027bool ABISysV_ppc64::RegisterIsVolatile(const RegisterInfo *reg_info) {
1028 return !RegisterIsCalleeSaved(reg_info);
1029}
1030
1031// See "Register Usage" in the
1032// "System V Application Binary Interface"
1033// "64-bit PowerPC ELF Application Binary Interface Supplement" current version
1034// is 2 released 2015 at
1035// https://members.openpowerfoundation.org/document/dl/576
1036bool ABISysV_ppc64::RegisterIsCalleeSaved(const RegisterInfo *reg_info) {
1037 if (reg_info) {
1038 // Preserved registers are :
1039 // r1,r2,r13-r31
1040 // cr2-cr4 (partially preserved)
1041 // f14-f31 (not yet)
1042 // v20-v31 (not yet)
1043 // vrsave (not yet)
1044
1045 const char *name = reg_info->name;
1046 if (name[0] == 'r') {
1047 if ((name[1] == '1' || name[1] == '2') && name[2] == '\0')
1048 return true;
1049 if (name[1] == '1' && name[2] > '2')
1050 return true;
1051 if ((name[1] == '2' || name[1] == '3') && name[2] != '\0')
1052 return true;
1053 }
1054
1055 if (name[0] == 'f' && name[1] >= '0' && name[2] <= '9') {
1056 if (name[2] == '\0')
1057 return false;
1058 if (name[1] == '1' && name[2] >= '4')
1059 return true;
1060 if ((name[1] == '2' || name[1] == '3') && name[2] != '\0')
1061 return true;
1062 }
1063
1064 if (name[0] == 's' && name[1] == 'p' && name[2] == '\0') // sp
1065 return true;
1066 if (name[0] == 'f' && name[1] == 'p' && name[2] == '\0') // fp
1067 return false;
1068 if (name[0] == 'p' && name[1] == 'c' && name[2] == '\0') // pc
1069 return true;
1070 }
1071 return false;
1072}
1073
1074void ABISysV_ppc64::Initialize() {
1075 PluginManager::RegisterPlugin(
1076 name: GetPluginNameStatic(), description: "System V ABI for ppc64 targets", create_callback: CreateInstance);
1077}
1078
1079void ABISysV_ppc64::Terminate() {
1080 PluginManager::UnregisterPlugin(create_callback: CreateInstance);
1081}
1082

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