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ABISysV_x86_64.cpp
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1//===-- ABISysV_x86_64.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_x86_64.h"
10
11#include "llvm/ADT/STLExtras.h"
12#include "llvm/ADT/StringSwitch.h"
13#include "llvm/ADT/Triple.h"
14
15#include "lldb/Core/Module.h"
17#include "lldb/Core/Value.h"
22#include "lldb/Target/Process.h"
25#include "lldb/Target/Target.h"
26#include "lldb/Target/Thread.h"
30#include "lldb/Utility/Log.h"
32#include "lldb/Utility/Status.h"
33
34#include <optional>
35#include <vector>
36
37using namespace lldb;
38using namespace lldb_private;
39
41
60};
61
63 name = "rax";
64 return true;
65}
66
67size_t ABISysV_x86_64::GetRedZoneSize() const { return 128; }
68
69// Static Functions
70
71ABISP
72ABISysV_x86_64::CreateInstance(lldb::ProcessSP process_sp, const ArchSpec &arch) {
73 const llvm::Triple::ArchType arch_type = arch.GetTriple().getArch();
74 const llvm::Triple::OSType os_type = arch.GetTriple().getOS();
75 const llvm::Triple::EnvironmentType os_env =
76 arch.GetTriple().getEnvironment();
77 if (arch_type == llvm::Triple::x86_64) {
78 switch(os_type) {
79 case llvm::Triple::OSType::IOS:
80 case llvm::Triple::OSType::TvOS:
81 case llvm::Triple::OSType::WatchOS:
82 switch (os_env) {
83 case llvm::Triple::EnvironmentType::MacABI:
84 case llvm::Triple::EnvironmentType::Simulator:
85 case llvm::Triple::EnvironmentType::UnknownEnvironment:
86 // UnknownEnvironment is needed for older compilers that don't
87 // support the simulator environment.
88 return ABISP(new ABISysV_x86_64(std::move(process_sp),
89 MakeMCRegisterInfo(arch)));
90 default:
91 return ABISP();
92 }
93 case llvm::Triple::OSType::Darwin:
94 case llvm::Triple::OSType::FreeBSD:
95 case llvm::Triple::OSType::Linux:
96 case llvm::Triple::OSType::MacOSX:
97 case llvm::Triple::OSType::NetBSD:
98 case llvm::Triple::OSType::Solaris:
99 case llvm::Triple::OSType::UnknownOS:
100 return ABISP(
101 new ABISysV_x86_64(std::move(process_sp), MakeMCRegisterInfo(arch)));
102 default:
103 return ABISP();
104 }
105 }
106 return ABISP();
107}
108
110 addr_t func_addr, addr_t return_addr,
111 llvm::ArrayRef<addr_t> args) const {
112 Log *log = GetLog(LLDBLog::Expressions);
113
114 if (log) {
115 StreamString s;
116 s.Printf("ABISysV_x86_64::PrepareTrivialCall (tid = 0x%" PRIx64
117 ", sp = 0x%" PRIx64 ", func_addr = 0x%" PRIx64
118 ", return_addr = 0x%" PRIx64,
119 thread.GetID(), (uint64_t)sp, (uint64_t)func_addr,
120 (uint64_t)return_addr);
121
122 for (size_t i = 0; i < args.size(); ++i)
123 s.Printf(", arg%" PRIu64 " = 0x%" PRIx64, static_cast<uint64_t>(i + 1),
124 args[i]);
125 s.PutCString(")");
126 log->PutString(s.GetString());
127 }
128
129 RegisterContext *reg_ctx = thread.GetRegisterContext().get();
130 if (!reg_ctx)
131 return false;
132
133 const RegisterInfo *reg_info = nullptr;
134
135 if (args.size() > 6) // TODO handle more than 6 arguments
136 return false;
137
138 for (size_t i = 0; i < args.size(); ++i) {
139 reg_info = reg_ctx->GetRegisterInfo(eRegisterKindGeneric,
141 LLDB_LOGF(log, "About to write arg%" PRIu64 " (0x%" PRIx64 ") into %s",
142 static_cast<uint64_t>(i + 1), args[i], reg_info->name);
143 if (!reg_ctx->WriteRegisterFromUnsigned(reg_info, args[i]))
144 return false;
145 }
146
147 // First, align the SP
148
149 LLDB_LOGF(log, "16-byte aligning SP: 0x%" PRIx64 " to 0x%" PRIx64,
150 (uint64_t)sp, (uint64_t)(sp & ~0xfull));
151
152 sp &= ~(0xfull); // 16-byte alignment
153
154 sp -= 8;
155
157 const RegisterInfo *pc_reg_info =
159 const RegisterInfo *sp_reg_info =
161 ProcessSP process_sp(thread.GetProcess());
162
163 RegisterValue reg_value;
164 LLDB_LOGF(log,
165 "Pushing the return address onto the stack: 0x%" PRIx64
166 ": 0x%" PRIx64,
167 (uint64_t)sp, (uint64_t)return_addr);
168
169 // Save return address onto the stack
170 if (!process_sp->WritePointerToMemory(sp, return_addr, error))
171 return false;
172
173 // %rsp is set to the actual stack value.
174
175 LLDB_LOGF(log, "Writing SP: 0x%" PRIx64, (uint64_t)sp);
176
177 if (!reg_ctx->WriteRegisterFromUnsigned(sp_reg_info, sp))
178 return false;
179
180 // %rip is set to the address of the called function.
181
182 LLDB_LOGF(log, "Writing IP: 0x%" PRIx64, (uint64_t)func_addr);
183
184 if (!reg_ctx->WriteRegisterFromUnsigned(pc_reg_info, func_addr))
185 return false;
186
187 return true;
188}
189
190static bool ReadIntegerArgument(Scalar &scalar, unsigned int bit_width,
191 bool is_signed, Thread &thread,
192 uint32_t *argument_register_ids,
193 unsigned int &current_argument_register,
194 addr_t &current_stack_argument) {
195 if (bit_width > 64)
196 return false; // Scalar can't hold large integer arguments
197
198 if (current_argument_register < 6) {
199 scalar = thread.GetRegisterContext()->ReadRegisterAsUnsigned(
200 argument_register_ids[current_argument_register], 0);
201 current_argument_register++;
202 if (is_signed)
203 scalar.SignExtend(bit_width);
204 } else {
205 uint32_t byte_size = (bit_width + (8 - 1)) / 8;
207 if (thread.GetProcess()->ReadScalarIntegerFromMemory(
208 current_stack_argument, byte_size, is_signed, scalar, error)) {
209 current_stack_argument += byte_size;
210 return true;
211 }
212 return false;
213 }
214 return true;
215}
216
218 ValueList &values) const {
219 unsigned int num_values = values.GetSize();
220 unsigned int value_index;
221
222 // Extract the register context so we can read arguments from registers
223
224 RegisterContext *reg_ctx = thread.GetRegisterContext().get();
225
226 if (!reg_ctx)
227 return false;
228
229 // Get the pointer to the first stack argument so we have a place to start
230 // when reading data
231
232 addr_t sp = reg_ctx->GetSP(0);
233
234 if (!sp)
235 return false;
236
237 addr_t current_stack_argument = sp + 8; // jump over return address
238
239 uint32_t argument_register_ids[6];
240
241 argument_register_ids[0] =
243 ->kinds[eRegisterKindLLDB];
244 argument_register_ids[1] =
246 ->kinds[eRegisterKindLLDB];
247 argument_register_ids[2] =
249 ->kinds[eRegisterKindLLDB];
250 argument_register_ids[3] =
252 ->kinds[eRegisterKindLLDB];
253 argument_register_ids[4] =
255 ->kinds[eRegisterKindLLDB];
256 argument_register_ids[5] =
258 ->kinds[eRegisterKindLLDB];
259
260 unsigned int current_argument_register = 0;
261
262 for (value_index = 0; value_index < num_values; ++value_index) {
263 Value *value = values.GetValueAtIndex(value_index);
264
265 if (!value)
266 return false;
267
268 // We currently only support extracting values with Clang QualTypes. Do we
269 // care about others?
270 CompilerType compiler_type = value->GetCompilerType();
271 std::optional<uint64_t> bit_size = compiler_type.GetBitSize(&thread);
272 if (!bit_size)
273 return false;
274 bool is_signed;
275
276 if (compiler_type.IsIntegerOrEnumerationType(is_signed)) {
277 ReadIntegerArgument(value->GetScalar(), *bit_size, is_signed, thread,
278 argument_register_ids, current_argument_register,
279 current_stack_argument);
280 } else if (compiler_type.IsPointerType()) {
281 ReadIntegerArgument(value->GetScalar(), *bit_size, false, thread,
282 argument_register_ids, current_argument_register,
283 current_stack_argument);
284 }
285 }
286
287 return true;
288}
289
290Status ABISysV_x86_64::SetReturnValueObject(lldb::StackFrameSP &frame_sp,
291 lldb::ValueObjectSP &new_value_sp) {
293 if (!new_value_sp) {
294 error.SetErrorString("Empty value object for return value.");
295 return error;
296 }
297
298 CompilerType compiler_type = new_value_sp->GetCompilerType();
299 if (!compiler_type) {
300 error.SetErrorString("Null clang type for return value.");
301 return error;
302 }
303
304 Thread *thread = frame_sp->GetThread().get();
305
306 bool is_signed;
307 uint32_t count;
308 bool is_complex;
309
310 RegisterContext *reg_ctx = thread->GetRegisterContext().get();
311
312 bool set_it_simple = false;
313 if (compiler_type.IsIntegerOrEnumerationType(is_signed) ||
314 compiler_type.IsPointerType()) {
315 const RegisterInfo *reg_info = reg_ctx->GetRegisterInfoByName("rax", 0);
316
317 DataExtractor data;
318 Status data_error;
319 size_t num_bytes = new_value_sp->GetData(data, data_error);
320 if (data_error.Fail()) {
321 error.SetErrorStringWithFormat(
322 "Couldn't convert return value to raw data: %s",
323 data_error.AsCString());
324 return error;
325 }
326 lldb::offset_t offset = 0;
327 if (num_bytes <= 8) {
328 uint64_t raw_value = data.GetMaxU64(&offset, num_bytes);
329
330 if (reg_ctx->WriteRegisterFromUnsigned(reg_info, raw_value))
331 set_it_simple = true;
332 } else {
333 error.SetErrorString("We don't support returning longer than 64 bit "
334 "integer values at present.");
335 }
336 } else if (compiler_type.IsFloatingPointType(count, is_complex)) {
337 if (is_complex)
338 error.SetErrorString(
339 "We don't support returning complex values at present");
340 else {
341 std::optional<uint64_t> bit_width =
342 compiler_type.GetBitSize(frame_sp.get());
343 if (!bit_width) {
344 error.SetErrorString("can't get type size");
345 return error;
346 }
347 if (*bit_width <= 64) {
348 const RegisterInfo *xmm0_info =
349 reg_ctx->GetRegisterInfoByName("xmm0", 0);
350 RegisterValue xmm0_value;
351 DataExtractor data;
352 Status data_error;
353 size_t num_bytes = new_value_sp->GetData(data, data_error);
354 if (data_error.Fail()) {
355 error.SetErrorStringWithFormat(
356 "Couldn't convert return value to raw data: %s",
357 data_error.AsCString());
358 return error;
359 }
360
361 unsigned char buffer[16];
362 ByteOrder byte_order = data.GetByteOrder();
363
364 data.CopyByteOrderedData(0, num_bytes, buffer, 16, byte_order);
365 xmm0_value.SetBytes(buffer, 16, byte_order);
366 reg_ctx->WriteRegister(xmm0_info, xmm0_value);
367 set_it_simple = true;
368 } else {
369 // FIXME - don't know how to do 80 bit long doubles yet.
370 error.SetErrorString(
371 "We don't support returning float values > 64 bits at present");
372 }
373 }
374 }
375
376 if (!set_it_simple) {
377 // Okay we've got a structure or something that doesn't fit in a simple
378 // register. We should figure out where it really goes, but we don't
379 // support this yet.
380 error.SetErrorString("We only support setting simple integer and float "
381 "return types at present.");
382 }
383
384 return error;
385}
386
388 Thread &thread, CompilerType &return_compiler_type) const {
389 ValueObjectSP return_valobj_sp;
390 Value value;
391
392 if (!return_compiler_type)
393 return return_valobj_sp;
394
395 // value.SetContext (Value::eContextTypeClangType, return_value_type);
396 value.SetCompilerType(return_compiler_type);
397
398 RegisterContext *reg_ctx = thread.GetRegisterContext().get();
399 if (!reg_ctx)
400 return return_valobj_sp;
401
402 const uint32_t type_flags = return_compiler_type.GetTypeInfo();
403 if (type_flags & eTypeIsScalar) {
404 value.SetValueType(Value::ValueType::Scalar);
405
406 bool success = false;
407 if (type_flags & eTypeIsInteger) {
408 // Extract the register context so we can read arguments from registers
409
410 std::optional<uint64_t> byte_size =
411 return_compiler_type.GetByteSize(&thread);
412 if (!byte_size)
413 return return_valobj_sp;
414 uint64_t raw_value = thread.GetRegisterContext()->ReadRegisterAsUnsigned(
415 reg_ctx->GetRegisterInfoByName("rax", 0), 0);
416 const bool is_signed = (type_flags & eTypeIsSigned) != 0;
417 switch (*byte_size) {
418 default:
419 break;
420
421 case sizeof(uint64_t):
422 if (is_signed)
423 value.GetScalar() = (int64_t)(raw_value);
424 else
425 value.GetScalar() = (uint64_t)(raw_value);
426 success = true;
427 break;
428
429 case sizeof(uint32_t):
430 if (is_signed)
431 value.GetScalar() = (int32_t)(raw_value & UINT32_MAX);
432 else
433 value.GetScalar() = (uint32_t)(raw_value & UINT32_MAX);
434 success = true;
435 break;
436
437 case sizeof(uint16_t):
438 if (is_signed)
439 value.GetScalar() = (int16_t)(raw_value & UINT16_MAX);
440 else
441 value.GetScalar() = (uint16_t)(raw_value & UINT16_MAX);
442 success = true;
443 break;
444
445 case sizeof(uint8_t):
446 if (is_signed)
447 value.GetScalar() = (int8_t)(raw_value & UINT8_MAX);
448 else
449 value.GetScalar() = (uint8_t)(raw_value & UINT8_MAX);
450 success = true;
451 break;
452 }
453 } else if (type_flags & eTypeIsFloat) {
454 if (type_flags & eTypeIsComplex) {
455 // Don't handle complex yet.
456 } else {
457 std::optional<uint64_t> byte_size =
458 return_compiler_type.GetByteSize(&thread);
459 if (byte_size && *byte_size <= sizeof(long double)) {
460 const RegisterInfo *xmm0_info =
461 reg_ctx->GetRegisterInfoByName("xmm0", 0);
462 RegisterValue xmm0_value;
463 if (reg_ctx->ReadRegister(xmm0_info, xmm0_value)) {
464 DataExtractor data;
465 if (xmm0_value.GetData(data)) {
466 lldb::offset_t offset = 0;
467 if (*byte_size == sizeof(float)) {
468 value.GetScalar() = (float)data.GetFloat(&offset);
469 success = true;
470 } else if (*byte_size == sizeof(double)) {
471 value.GetScalar() = (double)data.GetDouble(&offset);
472 success = true;
473 } else if (*byte_size == sizeof(long double)) {
474 // Don't handle long double since that can be encoded as 80 bit
475 // floats...
476 }
477 }
478 }
479 }
480 }
481 }
482
483 if (success)
484 return_valobj_sp = ValueObjectConstResult::Create(
485 thread.GetStackFrameAtIndex(0).get(), value, ConstString(""));
486 } else if (type_flags & eTypeIsPointer) {
487 unsigned rax_id =
488 reg_ctx->GetRegisterInfoByName("rax", 0)->kinds[eRegisterKindLLDB];
489 value.GetScalar() =
490 (uint64_t)thread.GetRegisterContext()->ReadRegisterAsUnsigned(rax_id,
491 0);
492 value.SetValueType(Value::ValueType::Scalar);
493 return_valobj_sp = ValueObjectConstResult::Create(
494 thread.GetStackFrameAtIndex(0).get(), value, ConstString(""));
495 } else if (type_flags & eTypeIsVector) {
496 std::optional<uint64_t> byte_size =
497 return_compiler_type.GetByteSize(&thread);
498 if (byte_size && *byte_size > 0) {
499 const RegisterInfo *altivec_reg =
500 reg_ctx->GetRegisterInfoByName("xmm0", 0);
501 if (altivec_reg == nullptr)
502 altivec_reg = reg_ctx->GetRegisterInfoByName("mm0", 0);
503
504 if (altivec_reg) {
505 if (*byte_size <= altivec_reg->byte_size) {
506 ProcessSP process_sp(thread.GetProcess());
507 if (process_sp) {
508 std::unique_ptr<DataBufferHeap> heap_data_up(
509 new DataBufferHeap(*byte_size, 0));
510 const ByteOrder byte_order = process_sp->GetByteOrder();
511 RegisterValue reg_value;
512 if (reg_ctx->ReadRegister(altivec_reg, reg_value)) {
514 if (reg_value.GetAsMemoryData(
515 *altivec_reg, heap_data_up->GetBytes(),
516 heap_data_up->GetByteSize(), byte_order, error)) {
517 DataExtractor data(DataBufferSP(heap_data_up.release()),
518 byte_order,
519 process_sp->GetTarget()
520 .GetArchitecture()
521 .GetAddressByteSize());
522 return_valobj_sp = ValueObjectConstResult::Create(
523 &thread, return_compiler_type, ConstString(""), data);
524 }
525 }
526 }
527 } else if (*byte_size <= altivec_reg->byte_size * 2) {
528 const RegisterInfo *altivec_reg2 =
529 reg_ctx->GetRegisterInfoByName("xmm1", 0);
530 if (altivec_reg2) {
531 ProcessSP process_sp(thread.GetProcess());
532 if (process_sp) {
533 std::unique_ptr<DataBufferHeap> heap_data_up(
534 new DataBufferHeap(*byte_size, 0));
535 const ByteOrder byte_order = process_sp->GetByteOrder();
536 RegisterValue reg_value;
537 RegisterValue reg_value2;
538 if (reg_ctx->ReadRegister(altivec_reg, reg_value) &&
539 reg_ctx->ReadRegister(altivec_reg2, reg_value2)) {
540
542 if (reg_value.GetAsMemoryData(
543 *altivec_reg, heap_data_up->GetBytes(),
544 altivec_reg->byte_size, byte_order, error) &&
545 reg_value2.GetAsMemoryData(
546 *altivec_reg2,
547 heap_data_up->GetBytes() + altivec_reg->byte_size,
548 heap_data_up->GetByteSize() - altivec_reg->byte_size,
549 byte_order, error)) {
550 DataExtractor data(DataBufferSP(heap_data_up.release()),
551 byte_order,
552 process_sp->GetTarget()
553 .GetArchitecture()
554 .GetAddressByteSize());
555 return_valobj_sp = ValueObjectConstResult::Create(
556 &thread, return_compiler_type, ConstString(""), data);
557 }
558 }
559 }
560 }
561 }
562 }
563 }
564 }
565
566 return return_valobj_sp;
567}
568
569// The compiler will flatten the nested aggregate type into single
570// layer and push the value to stack
571// This helper function will flatten an aggregate type
572// and return true if it can be returned in register(s) by value
573// return false if the aggregate is in memory
575 Thread &thread, ExecutionContext &exe_ctx,
576 CompilerType &return_compiler_type,
577 uint32_t data_byte_offset,
578 std::vector<uint32_t> &aggregate_field_offsets,
579 std::vector<CompilerType> &aggregate_compiler_types) {
580
581 const uint32_t num_children = return_compiler_type.GetNumFields();
582 for (uint32_t idx = 0; idx < num_children; ++idx) {
583 std::string name;
584 bool is_signed;
585 uint32_t count;
586 bool is_complex;
587
588 uint64_t field_bit_offset = 0;
589 CompilerType field_compiler_type = return_compiler_type.GetFieldAtIndex(
590 idx, name, &field_bit_offset, nullptr, nullptr);
591 std::optional<uint64_t> field_bit_width =
592 field_compiler_type.GetBitSize(&thread);
593
594 // if we don't know the size of the field (e.g. invalid type), exit
595 if (!field_bit_width || *field_bit_width == 0) {
596 return false;
597 }
598
599 uint32_t field_byte_offset = field_bit_offset / 8 + data_byte_offset;
600
601 const uint32_t field_type_flags = field_compiler_type.GetTypeInfo();
602 if (field_compiler_type.IsIntegerOrEnumerationType(is_signed) ||
603 field_compiler_type.IsPointerType() ||
604 field_compiler_type.IsFloatingPointType(count, is_complex)) {
605 aggregate_field_offsets.push_back(field_byte_offset);
606 aggregate_compiler_types.push_back(field_compiler_type);
607 } else if (field_type_flags & eTypeHasChildren) {
608 if (!FlattenAggregateType(thread, exe_ctx, field_compiler_type,
609 field_byte_offset, aggregate_field_offsets,
610 aggregate_compiler_types)) {
611 return false;
612 }
613 }
614 }
615 return true;
616}
617
619 Thread &thread, CompilerType &return_compiler_type) const {
620 ValueObjectSP return_valobj_sp;
621
622 if (!return_compiler_type)
623 return return_valobj_sp;
624
625 ExecutionContext exe_ctx(thread.shared_from_this());
626 return_valobj_sp = GetReturnValueObjectSimple(thread, return_compiler_type);
627 if (return_valobj_sp)
628 return return_valobj_sp;
629
630 RegisterContextSP reg_ctx_sp = thread.GetRegisterContext();
631 if (!reg_ctx_sp)
632 return return_valobj_sp;
633
634 std::optional<uint64_t> bit_width = return_compiler_type.GetBitSize(&thread);
635 if (!bit_width)
636 return return_valobj_sp;
637 if (return_compiler_type.IsAggregateType()) {
638 Target *target = exe_ctx.GetTargetPtr();
639 bool is_memory = true;
640 std::vector<uint32_t> aggregate_field_offsets;
641 std::vector<CompilerType> aggregate_compiler_types;
642 auto ts = return_compiler_type.GetTypeSystem();
643 if (ts && ts->CanPassInRegisters(return_compiler_type) &&
644 *bit_width <= 128 &&
645 FlattenAggregateType(thread, exe_ctx, return_compiler_type, 0,
646 aggregate_field_offsets,
647 aggregate_compiler_types)) {
648 ByteOrder byte_order = target->GetArchitecture().GetByteOrder();
649 WritableDataBufferSP data_sp(new DataBufferHeap(16, 0));
650 DataExtractor return_ext(data_sp, byte_order,
652
653 const RegisterInfo *rax_info =
654 reg_ctx_sp->GetRegisterInfoByName("rax", 0);
655 const RegisterInfo *rdx_info =
656 reg_ctx_sp->GetRegisterInfoByName("rdx", 0);
657 const RegisterInfo *xmm0_info =
658 reg_ctx_sp->GetRegisterInfoByName("xmm0", 0);
659 const RegisterInfo *xmm1_info =
660 reg_ctx_sp->GetRegisterInfoByName("xmm1", 0);
661
662 RegisterValue rax_value, rdx_value, xmm0_value, xmm1_value;
663 reg_ctx_sp->ReadRegister(rax_info, rax_value);
664 reg_ctx_sp->ReadRegister(rdx_info, rdx_value);
665 reg_ctx_sp->ReadRegister(xmm0_info, xmm0_value);
666 reg_ctx_sp->ReadRegister(xmm1_info, xmm1_value);
667
668 DataExtractor rax_data, rdx_data, xmm0_data, xmm1_data;
669
670 rax_value.GetData(rax_data);
671 rdx_value.GetData(rdx_data);
672 xmm0_value.GetData(xmm0_data);
673 xmm1_value.GetData(xmm1_data);
674
675 uint32_t fp_bytes =
676 0; // Tracks how much of the xmm registers we've consumed so far
677 uint32_t integer_bytes =
678 0; // Tracks how much of the rax/rds registers we've consumed so far
679
680 // in case of the returned type is a subclass of non-abstract-base class
681 // it will have a padding to skip the base content
682 if (aggregate_field_offsets.size()) {
683 fp_bytes = aggregate_field_offsets[0];
684 integer_bytes = aggregate_field_offsets[0];
685 }
686
687 const uint32_t num_children = aggregate_compiler_types.size();
688
689 // Since we are in the small struct regime, assume we are not in memory.
690 is_memory = false;
691 for (uint32_t idx = 0; idx < num_children; idx++) {
692 bool is_signed;
693 uint32_t count;
694 bool is_complex;
695
696 CompilerType field_compiler_type = aggregate_compiler_types[idx];
697 uint32_t field_byte_width = (uint32_t) (*field_compiler_type.GetByteSize(&thread));
698 uint32_t field_byte_offset = aggregate_field_offsets[idx];
699
700 uint32_t field_bit_width = field_byte_width * 8;
701
702 DataExtractor *copy_from_extractor = nullptr;
703 uint32_t copy_from_offset = 0;
704
705 if (field_compiler_type.IsIntegerOrEnumerationType(is_signed) ||
706 field_compiler_type.IsPointerType()) {
707 if (integer_bytes < 8) {
708 if (integer_bytes + field_byte_width <= 8) {
709 // This is in RAX, copy from register to our result structure:
710 copy_from_extractor = &rax_data;
711 copy_from_offset = integer_bytes;
712 integer_bytes += field_byte_width;
713 } else {
714 // The next field wouldn't fit in the remaining space, so we
715 // pushed it to rdx.
716 copy_from_extractor = &rdx_data;
717 copy_from_offset = 0;
718 integer_bytes = 8 + field_byte_width;
719 }
720 } else if (integer_bytes + field_byte_width <= 16) {
721 copy_from_extractor = &rdx_data;
722 copy_from_offset = integer_bytes - 8;
723 integer_bytes += field_byte_width;
724 } else {
725 // The last field didn't fit. I can't see how that would happen
726 // w/o the overall size being greater than 16 bytes. For now,
727 // return a nullptr return value object.
728 return return_valobj_sp;
729 }
730 } else if (field_compiler_type.IsFloatingPointType(count, is_complex)) {
731 // Structs with long doubles are always passed in memory.
732 if (field_bit_width == 128) {
733 is_memory = true;
734 break;
735 } else if (field_bit_width == 64) {
736 // These have to be in a single xmm register.
737 if (fp_bytes == 0)
738 copy_from_extractor = &xmm0_data;
739 else
740 copy_from_extractor = &xmm1_data;
741
742 copy_from_offset = 0;
743 fp_bytes += field_byte_width;
744 } else if (field_bit_width == 32) {
745 // This one is kind of complicated. If we are in an "eightbyte"
746 // with another float, we'll be stuffed into an xmm register with
747 // it. If we are in an "eightbyte" with one or more ints, then we
748 // will be stuffed into the appropriate GPR with them.
749 bool in_gpr;
750 if (field_byte_offset % 8 == 0) {
751 // We are at the beginning of one of the eightbytes, so check the
752 // next element (if any)
753 if (idx == num_children - 1) {
754 in_gpr = false;
755 } else {
756 CompilerType next_field_compiler_type =
757 aggregate_compiler_types[idx + 1];
758 if (next_field_compiler_type.IsIntegerOrEnumerationType(
759 is_signed)) {
760 in_gpr = true;
761 } else {
762 copy_from_offset = 0;
763 in_gpr = false;
764 }
765 }
766 } else if (field_byte_offset % 4 == 0) {
767 // We are inside of an eightbyte, so see if the field before us
768 // is floating point: This could happen if somebody put padding
769 // in the structure.
770 if (idx == 0) {
771 in_gpr = false;
772 } else {
773 CompilerType prev_field_compiler_type =
774 aggregate_compiler_types[idx - 1];
775 if (prev_field_compiler_type.IsIntegerOrEnumerationType(
776 is_signed)) {
777 in_gpr = true;
778 } else {
779 copy_from_offset = 4;
780 in_gpr = false;
781 }
782 }
783 } else {
784 is_memory = true;
785 continue;
786 }
787
788 // Okay, we've figured out whether we are in GPR or XMM, now figure
789 // out which one.
790 if (in_gpr) {
791 if (integer_bytes < 8) {
792 // This is in RAX, copy from register to our result structure:
793 copy_from_extractor = &rax_data;
794 copy_from_offset = integer_bytes;
795 integer_bytes += field_byte_width;
796 } else {
797 copy_from_extractor = &rdx_data;
798 copy_from_offset = integer_bytes - 8;
799 integer_bytes += field_byte_width;
800 }
801 } else {
802 if (fp_bytes < 8)
803 copy_from_extractor = &xmm0_data;
804 else
805 copy_from_extractor = &xmm1_data;
806
807 fp_bytes += field_byte_width;
808 }
809 }
810 }
811 // These two tests are just sanity checks. If I somehow get the type
812 // calculation wrong above it is better to just return nothing than to
813 // assert or crash.
814 if (!copy_from_extractor)
815 return return_valobj_sp;
816 if (copy_from_offset + field_byte_width >
817 copy_from_extractor->GetByteSize())
818 return return_valobj_sp;
819 copy_from_extractor->CopyByteOrderedData(
820 copy_from_offset, field_byte_width,
821 data_sp->GetBytes() + field_byte_offset, field_byte_width,
822 byte_order);
823 }
824 if (!is_memory) {
825 // The result is in our data buffer. Let's make a variable object out
826 // of it:
827 return_valobj_sp = ValueObjectConstResult::Create(
828 &thread, return_compiler_type, ConstString(""), return_ext);
829 }
830 }
831
832 // FIXME: This is just taking a guess, rax may very well no longer hold the
833 // return storage location.
834 // If we are going to do this right, when we make a new frame we should
835 // check to see if it uses a memory return, and if we are at the first
836 // instruction and if so stash away the return location. Then we would
837 // only return the memory return value if we know it is valid.
838
839 if (is_memory) {
840 unsigned rax_id =
841 reg_ctx_sp->GetRegisterInfoByName("rax", 0)->kinds[eRegisterKindLLDB];
842 lldb::addr_t storage_addr =
843 (uint64_t)thread.GetRegisterContext()->ReadRegisterAsUnsigned(rax_id,
844 0);
845 return_valobj_sp = ValueObjectMemory::Create(
846 &thread, "", Address(storage_addr, nullptr), return_compiler_type);
847 }
848 }
849
850 return return_valobj_sp;
851}
852
853// This defines the CFA as rsp+8
854// the saved pc is at CFA-8 (i.e. rsp+0)
855// The saved rsp is CFA+0
856
858 unwind_plan.Clear();
860
861 uint32_t sp_reg_num = dwarf_rsp;
862 uint32_t pc_reg_num = dwarf_rip;
863
865 row->GetCFAValue().SetIsRegisterPlusOffset(sp_reg_num, 8);
866 row->SetRegisterLocationToAtCFAPlusOffset(pc_reg_num, -8, false);
867 row->SetRegisterLocationToIsCFAPlusOffset(sp_reg_num, 0, true);
868 unwind_plan.AppendRow(row);
869 unwind_plan.SetSourceName("x86_64 at-func-entry default");
871 return true;
872}
873
874// This defines the CFA as rbp+16
875// The saved pc is at CFA-8 (i.e. rbp+8)
876// The saved rbp is at CFA-16 (i.e. rbp+0)
877// The saved rsp is CFA+0
878
880 unwind_plan.Clear();
882
883 uint32_t fp_reg_num = dwarf_rbp;
884 uint32_t sp_reg_num = dwarf_rsp;
885 uint32_t pc_reg_num = dwarf_rip;
886
888
889 const int32_t ptr_size = 8;
890 row->GetCFAValue().SetIsRegisterPlusOffset(dwarf_rbp, 2 * ptr_size);
891 row->SetOffset(0);
892 row->SetUnspecifiedRegistersAreUndefined(true);
893
894 row->SetRegisterLocationToAtCFAPlusOffset(fp_reg_num, ptr_size * -2, true);
895 row->SetRegisterLocationToAtCFAPlusOffset(pc_reg_num, ptr_size * -1, true);
896 row->SetRegisterLocationToIsCFAPlusOffset(sp_reg_num, 0, true);
897
898 unwind_plan.AppendRow(row);
899 unwind_plan.SetSourceName("x86_64 default unwind plan");
903 return true;
904}
905
906bool ABISysV_x86_64::RegisterIsVolatile(const RegisterInfo *reg_info) {
907 return !RegisterIsCalleeSaved(reg_info);
908}
909
910// See "Register Usage" in the
911// "System V Application Binary Interface"
912// "AMD64 Architecture Processor Supplement" (or "x86-64(tm) Architecture
913// Processor Supplement" in earlier revisions) (this doc is also commonly
914// referred to as the x86-64/AMD64 psABI) Edited by Michael Matz, Jan Hubicka,
915// Andreas Jaeger, and Mark Mitchell current version is 0.99.6 released
916// 2012-07-02 at http://refspecs.linuxfoundation.org/elf/x86-64-abi-0.99.pdf
917// It's being revised & updated at https://github.com/hjl-tools/x86-psABI/
918
919bool ABISysV_x86_64::RegisterIsCalleeSaved(const RegisterInfo *reg_info) {
920 if (!reg_info)
921 return false;
922 assert(reg_info->name != nullptr && "unnamed register?");
923 std::string Name = std::string(reg_info->name);
924 bool IsCalleeSaved =
925 llvm::StringSwitch<bool>(Name)
926 .Cases("r12", "r13", "r14", "r15", "rbp", "ebp", "rbx", "ebx", true)
927 .Cases("rip", "eip", "rsp", "esp", "sp", "fp", "pc", true)
928 .Default(false);
929 return IsCalleeSaved;
930}
931
933 return llvm::StringSwitch<uint32_t>(name)
934 .Case("rip", LLDB_REGNUM_GENERIC_PC)
935 .Case("rsp", LLDB_REGNUM_GENERIC_SP)
936 .Case("rbp", LLDB_REGNUM_GENERIC_FP)
937 .Case("rflags", LLDB_REGNUM_GENERIC_FLAGS)
938 // gdbserver uses eflags
939 .Case("eflags", LLDB_REGNUM_GENERIC_FLAGS)
940 .Case("rdi", LLDB_REGNUM_GENERIC_ARG1)
941 .Case("rsi", LLDB_REGNUM_GENERIC_ARG2)
942 .Case("rdx", LLDB_REGNUM_GENERIC_ARG3)
943 .Case("rcx", LLDB_REGNUM_GENERIC_ARG4)
944 .Case("r8", LLDB_REGNUM_GENERIC_ARG5)
945 .Case("r9", LLDB_REGNUM_GENERIC_ARG6)
946 .Default(LLDB_INVALID_REGNUM);
947}
948
951 GetPluginNameStatic(), "System V ABI for x86_64 targets", CreateInstance);
952}
953
956}
dwarf_regnums
static bool 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)
static bool FlattenAggregateType(Thread &thread, ExecutionContext &exe_ctx, CompilerType &return_compiler_type, uint32_t data_byte_offset, std::vector< uint32_t > &aggregate_field_offsets, std::vector< CompilerType > &aggregate_compiler_types)
@ dwarf_rdi
@ dwarf_r12
@ dwarf_r13
@ dwarf_r8
@ dwarf_r11
@ dwarf_r9
@ dwarf_rcx
@ dwarf_rip
@ dwarf_rsi
@ dwarf_r15
@ dwarf_rax
@ dwarf_rsp
@ dwarf_rbp
@ dwarf_r10
@ dwarf_r14
@ dwarf_rdx
@ dwarf_rbx
static bool 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)
static llvm::raw_ostream & error(Stream &strm)
#define LLDB_LOGF(log,...)
Definition: Log.h:344
#define LLDB_PLUGIN_DEFINE(PluginName)
Definition: PluginManager.h:31
bool GetArgumentValues(lldb_private::Thread &thread, lldb_private::ValueList &values) const override
static void Terminate()
bool CreateDefaultUnwindPlan(lldb_private::UnwindPlan &unwind_plan) override
static lldb::ABISP CreateInstance(lldb::ProcessSP process_sp, const lldb_private::ArchSpec &arch)
bool RegisterIsCalleeSaved(const lldb_private::RegisterInfo *reg_info)
bool GetPointerReturnRegister(const char *&name) override
lldb_private::Status SetReturnValueObject(lldb::StackFrameSP &frame_sp, lldb::ValueObjectSP &new_value) override
uint32_t GetGenericNum(llvm::StringRef reg) override
Return the generic number of the given register.
lldb::ValueObjectSP GetReturnValueObjectImpl(lldb_private::Thread &thread, lldb_private::CompilerType &type) const override
static void Initialize()
size_t GetRedZoneSize() const override
lldb::ValueObjectSP GetReturnValueObjectSimple(lldb_private::Thread &thread, lldb_private::CompilerType &ast_type) const
static llvm::StringRef GetPluginNameStatic()
bool CreateFunctionEntryUnwindPlan(lldb_private::UnwindPlan &unwind_plan) override
bool RegisterIsVolatile(const lldb_private::RegisterInfo *reg_info) override
bool PrepareTrivialCall(lldb_private::Thread &thread, lldb::addr_t sp, lldb::addr_t functionAddress, lldb::addr_t returnAddress, llvm::ArrayRef< lldb::addr_t > args) const override
static std::unique_ptr< llvm::MCRegisterInfo > MakeMCRegisterInfo(const ArchSpec &arch)
Utility function to construct a MCRegisterInfo using the ArchSpec triple.
Definition: ABI.cpp:201
A section + offset based address class.
Definition: Address.h:59
An architecture specification class.
Definition: ArchSpec.h:32
uint32_t GetAddressByteSize() const
Returns the size in bytes of an address of the current architecture.
Definition: ArchSpec.cpp:694
llvm::Triple & GetTriple()
Architecture triple accessor.
Definition: ArchSpec.h:463
lldb::ByteOrder GetByteOrder() const
Returns the byte order for the architecture specification.
Definition: ArchSpec.cpp:741
Generic representation of a type in a programming language.
Definition: CompilerType.h:36
TypeSystemSPWrapper GetTypeSystem() const
Accessors.
std::optional< uint64_t > GetByteSize(ExecutionContextScope *exe_scope) const
Return the size of the type in bytes.
CompilerType GetFieldAtIndex(size_t idx, std::string &name, uint64_t *bit_offset_ptr, uint32_t *bitfield_bit_size_ptr, bool *is_bitfield_ptr) const
bool IsFloatingPointType(uint32_t &count, bool &is_complex) const
uint32_t GetNumFields() const
bool IsIntegerOrEnumerationType(bool &is_signed) const
uint32_t GetTypeInfo(CompilerType *pointee_or_element_compiler_type=nullptr) const
std::optional< uint64_t > GetBitSize(ExecutionContextScope *exe_scope) const
Return the size of the type in bits.
bool IsPointerType(CompilerType *pointee_type=nullptr) const
A uniqued constant string class.
Definition: ConstString.h:39
A subclass of DataBuffer that stores a data buffer on the heap.
An data extractor class.
Definition: DataExtractor.h:48
float GetFloat(lldb::offset_t *offset_ptr) const
Extract a float from *offset_ptr.
uint64_t GetByteSize() const
Get the number of bytes contained in this object.
uint64_t GetMaxU64(lldb::offset_t *offset_ptr, size_t byte_size) const
Extract an unsigned integer of size byte_size from *offset_ptr.
lldb::ByteOrder GetByteOrder() const
Get the current byte order value.
lldb::offset_t CopyByteOrderedData(lldb::offset_t src_offset, lldb::offset_t src_len, void *dst, lldb::offset_t dst_len, lldb::ByteOrder dst_byte_order) const
Copy dst_len bytes from *offset_ptr and ensure the copied data is treated as a value that can be swap...
double GetDouble(lldb::offset_t *offset_ptr) const
"lldb/Target/ExecutionContext.h" A class that contains an execution context.
Target * GetTargetPtr() const
Returns a pointer to the target object.
void PutString(llvm::StringRef str)
Definition: Log.cpp:135
static bool RegisterPlugin(llvm::StringRef name, llvm::StringRef description, ABICreateInstance create_callback)
static bool UnregisterPlugin(ABICreateInstance create_callback)
uint64_t GetSP(uint64_t fail_value=LLDB_INVALID_ADDRESS)
virtual bool WriteRegister(const RegisterInfo *reg_info, const RegisterValue &reg_value)=0
const RegisterInfo * GetRegisterInfo(lldb::RegisterKind reg_kind, uint32_t reg_num)
bool WriteRegisterFromUnsigned(uint32_t reg, uint64_t uval)
const RegisterInfo * GetRegisterInfoByName(llvm::StringRef reg_name, uint32_t start_idx=0)
virtual bool ReadRegister(const RegisterInfo *reg_info, RegisterValue &reg_value)=0
bool GetData(DataExtractor &data) const
uint32_t GetAsMemoryData(const RegisterInfo &reg_info, void *dst, uint32_t dst_len, lldb::ByteOrder dst_byte_order, Status &error) const
void SetBytes(const void *bytes, size_t length, lldb::ByteOrder byte_order)
bool SignExtend(uint32_t bit_pos)
Definition: Scalar.cpp:745
An error handling class.
Definition: Status.h:44
bool Fail() const
Test for error condition.
Definition: Status.cpp:181
const char * AsCString(const char *default_error_str="unknown error") const
Get the error string associated with the current error.
Definition: Status.cpp:130
llvm::StringRef GetString() const
size_t Printf(const char *format,...) __attribute__((format(printf
Output printf formatted output to the stream.
Definition: Stream.cpp:107
size_t PutCString(llvm::StringRef cstr)
Output a C string to the stream.
Definition: Stream.cpp:63
const ArchSpec & GetArchitecture() const
Definition: Target.h:988
virtual lldb::StackFrameSP GetStackFrameAtIndex(uint32_t idx)
Definition: Thread.h:399
virtual lldb::RegisterContextSP GetRegisterContext()=0
lldb::ProcessSP GetProcess() const
Definition: Thread.h:153
void SetUnwindPlanForSignalTrap(lldb_private::LazyBool is_for_signal_trap)
Definition: UnwindPlan.h:502
void SetRegisterKind(lldb::RegisterKind kind)
Definition: UnwindPlan.h:437
void AppendRow(const RowSP &row_sp)
Definition: UnwindPlan.cpp:362
std::shared_ptr< Row > RowSP
Definition: UnwindPlan.h:395
void SetSourcedFromCompiler(lldb_private::LazyBool from_compiler)
Definition: UnwindPlan.h:478
void SetSourceName(const char *)
Definition: UnwindPlan.cpp:564
void SetUnwindPlanValidAtAllInstructions(lldb_private::LazyBool valid_at_all_insn)
Definition: UnwindPlan.h:490
Value * GetValueAtIndex(size_t idx)
Definition: Value.cpp:670
static lldb::ValueObjectSP Create(ExecutionContextScope *exe_scope, lldb::ByteOrder byte_order, uint32_t addr_byte_size, lldb::addr_t address=LLDB_INVALID_ADDRESS)
static lldb::ValueObjectSP Create(ExecutionContextScope *exe_scope, llvm::StringRef name, const Address &address, lldb::TypeSP &type_sp)
const Scalar & GetScalar() const
Definition: Value.h:112
void SetCompilerType(const CompilerType &compiler_type)
Definition: Value.cpp:252
void SetValueType(ValueType value_type)
Definition: Value.h:89
const CompilerType & GetCompilerType()
Definition: Value.cpp:223
#define LLDB_REGNUM_GENERIC_ARG6
Definition: lldb-defines.h:66
#define LLDB_REGNUM_GENERIC_SP
Definition: lldb-defines.h:52
#define LLDB_REGNUM_GENERIC_ARG4
Definition: lldb-defines.h:62
#define LLDB_REGNUM_GENERIC_ARG3
Definition: lldb-defines.h:60
#define LLDB_REGNUM_GENERIC_ARG1
Definition: lldb-defines.h:56
#define LLDB_REGNUM_GENERIC_FLAGS
Definition: lldb-defines.h:55
#define UINT32_MAX
Definition: lldb-defines.h:19
#define LLDB_INVALID_REGNUM
Definition: lldb-defines.h:79
#define LLDB_REGNUM_GENERIC_ARG2
Definition: lldb-defines.h:58
#define LLDB_REGNUM_GENERIC_PC
Definition: lldb-defines.h:51
#define LLDB_REGNUM_GENERIC_FP
Definition: lldb-defines.h:53
#define LLDB_REGNUM_GENERIC_ARG5
Definition: lldb-defines.h:64
A class that represents a running process on the host machine.
Log * GetLog(Cat mask)
Retrieve the Log object for the channel associated with the given log enum.
Definition: Log.h:309
Definition: SBAddress.h:15
uint64_t offset_t
Definition: lldb-types.h:87
ByteOrder
Byte ordering definitions.
uint64_t addr_t
Definition: lldb-types.h:83
@ eRegisterKindGeneric
insn ptr reg, stack ptr reg, etc not specific to any particular target
@ eRegisterKindLLDB
lldb's internal register numbers
@ eRegisterKindDWARF
the register numbers seen DWARF
lldb::user_id_t GetID() const
Get accessor for the user ID.
Definition: UserID.h:47