1 //===-- ABISysV_arc.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_arc.h"
10
11 // C Includes
12 // C++ Includes
13 #include <array>
14 #include <limits>
15 #include <type_traits>
16
17 // Other libraries and framework includes
18 #include "llvm/ADT/Triple.h"
19 #include "llvm/IR/DerivedTypes.h"
20 #include "llvm/Support/MathExtras.h"
21
22 #include "lldb/Core/Module.h"
23 #include "lldb/Core/PluginManager.h"
24 #include "lldb/Core/Value.h"
25 #include "lldb/Core/ValueObjectConstResult.h"
26 #include "lldb/Core/ValueObjectMemory.h"
27 #include "lldb/Core/ValueObjectRegister.h"
28 #include "lldb/Symbol/UnwindPlan.h"
29 #include "lldb/Target/Process.h"
30 #include "lldb/Target/RegisterContext.h"
31 #include "lldb/Target/StackFrame.h"
32 #include "lldb/Target/Target.h"
33 #include "lldb/Target/Thread.h"
34 #include "lldb/Utility/ConstString.h"
35 #include "lldb/Utility/RegisterValue.h"
36 #include "lldb/Utility/Status.h"
37
38 #define DEFINE_REG_NAME(reg_num) ConstString(#reg_num).GetCString()
39 #define DEFINE_REG_NAME_STR(reg_name) ConstString(reg_name).GetCString()
40
41 // The ABI is not a source of such information as size, offset, encoding, etc.
42 // of a register. Just provides correct dwarf and eh_frame numbers.
43
44 #define DEFINE_GENERIC_REGISTER_STUB(dwarf_num, str_name, generic_num) \
45 { \
46 DEFINE_REG_NAME(dwarf_num), DEFINE_REG_NAME_STR(str_name), \
47 0, 0, eEncodingInvalid, eFormatDefault, \
48 { dwarf_num, dwarf_num, generic_num, LLDB_INVALID_REGNUM, dwarf_num }, \
49 nullptr, nullptr, nullptr, 0 \
50 }
51
52 #define DEFINE_REGISTER_STUB(dwarf_num, str_name) \
53 DEFINE_GENERIC_REGISTER_STUB(dwarf_num, str_name, LLDB_INVALID_REGNUM)
54
55 using namespace lldb;
56 using namespace lldb_private;
57
58 LLDB_PLUGIN_DEFINE_ADV(ABISysV_arc, ABIARC)
59
60 namespace {
61 namespace dwarf {
62 enum regnums {
63 r0, r1, r2, r3, r4, r5, r6, r7, r8, r9, r10, r11, r12, r13, r14, r15, r16,
64 r17, r18, r19, r20, r21, r22, r23, r24, r25, r26,
65 r27, fp = r27, r28, sp = r28, r29, r30, r31, blink = r31,
66 r32, r33, r34, r35, r36, r37, r38, r39, r40, r41, r42, r43, r44, r45, r46,
67 r47, r48, r49, r50, r51, r52, r53, r54, r55, r56, r57, r58, r59, r60,
68 /*reserved,*/ /*limm indicator,*/ r63 = 63, pc = 70, status32 = 74
69 };
70
71 static const std::array<RegisterInfo, 64> g_register_infos = { {
72 DEFINE_GENERIC_REGISTER_STUB(r0, nullptr, LLDB_REGNUM_GENERIC_ARG1),
73 DEFINE_GENERIC_REGISTER_STUB(r1, nullptr, LLDB_REGNUM_GENERIC_ARG2),
74 DEFINE_GENERIC_REGISTER_STUB(r2, nullptr, LLDB_REGNUM_GENERIC_ARG3),
75 DEFINE_GENERIC_REGISTER_STUB(r3, nullptr, LLDB_REGNUM_GENERIC_ARG4),
76 DEFINE_GENERIC_REGISTER_STUB(r4, nullptr, LLDB_REGNUM_GENERIC_ARG5),
77 DEFINE_GENERIC_REGISTER_STUB(r5, nullptr, LLDB_REGNUM_GENERIC_ARG6),
78 DEFINE_GENERIC_REGISTER_STUB(r6, nullptr, LLDB_REGNUM_GENERIC_ARG7),
79 DEFINE_GENERIC_REGISTER_STUB(r7, nullptr, LLDB_REGNUM_GENERIC_ARG8),
80 DEFINE_REGISTER_STUB(r8, nullptr),
81 DEFINE_REGISTER_STUB(r9, nullptr),
82 DEFINE_REGISTER_STUB(r10, nullptr),
83 DEFINE_REGISTER_STUB(r11, nullptr),
84 DEFINE_REGISTER_STUB(r12, nullptr),
85 DEFINE_REGISTER_STUB(r13, nullptr),
86 DEFINE_REGISTER_STUB(r14, nullptr),
87 DEFINE_REGISTER_STUB(r15, nullptr),
88 DEFINE_REGISTER_STUB(r16, nullptr),
89 DEFINE_REGISTER_STUB(r17, nullptr),
90 DEFINE_REGISTER_STUB(r18, nullptr),
91 DEFINE_REGISTER_STUB(r19, nullptr),
92 DEFINE_REGISTER_STUB(r20, nullptr),
93 DEFINE_REGISTER_STUB(r21, nullptr),
94 DEFINE_REGISTER_STUB(r22, nullptr),
95 DEFINE_REGISTER_STUB(r23, nullptr),
96 DEFINE_REGISTER_STUB(r24, nullptr),
97 DEFINE_REGISTER_STUB(r25, nullptr),
98 DEFINE_REGISTER_STUB(r26, "gp"),
99 DEFINE_GENERIC_REGISTER_STUB(r27, "fp", LLDB_REGNUM_GENERIC_FP),
100 DEFINE_GENERIC_REGISTER_STUB(r28, "sp", LLDB_REGNUM_GENERIC_SP),
101 DEFINE_REGISTER_STUB(r29, "ilink"),
102 DEFINE_REGISTER_STUB(r30, nullptr),
103 DEFINE_GENERIC_REGISTER_STUB(r31, "blink", LLDB_REGNUM_GENERIC_RA),
104 DEFINE_REGISTER_STUB(r32, nullptr),
105 DEFINE_REGISTER_STUB(r33, nullptr),
106 DEFINE_REGISTER_STUB(r34, nullptr),
107 DEFINE_REGISTER_STUB(r35, nullptr),
108 DEFINE_REGISTER_STUB(r36, nullptr),
109 DEFINE_REGISTER_STUB(r37, nullptr),
110 DEFINE_REGISTER_STUB(r38, nullptr),
111 DEFINE_REGISTER_STUB(r39, nullptr),
112 DEFINE_REGISTER_STUB(r40, nullptr),
113 DEFINE_REGISTER_STUB(r41, nullptr),
114 DEFINE_REGISTER_STUB(r42, nullptr),
115 DEFINE_REGISTER_STUB(r43, nullptr),
116 DEFINE_REGISTER_STUB(r44, nullptr),
117 DEFINE_REGISTER_STUB(r45, nullptr),
118 DEFINE_REGISTER_STUB(r46, nullptr),
119 DEFINE_REGISTER_STUB(r47, nullptr),
120 DEFINE_REGISTER_STUB(r48, nullptr),
121 DEFINE_REGISTER_STUB(r49, nullptr),
122 DEFINE_REGISTER_STUB(r50, nullptr),
123 DEFINE_REGISTER_STUB(r51, nullptr),
124 DEFINE_REGISTER_STUB(r52, nullptr),
125 DEFINE_REGISTER_STUB(r53, nullptr),
126 DEFINE_REGISTER_STUB(r54, nullptr),
127 DEFINE_REGISTER_STUB(r55, nullptr),
128 DEFINE_REGISTER_STUB(r56, nullptr),
129 DEFINE_REGISTER_STUB(r57, nullptr),
130 DEFINE_REGISTER_STUB(r58, "accl"),
131 DEFINE_REGISTER_STUB(r59, "acch"),
132 DEFINE_REGISTER_STUB(r60, "lp_count"),
133 DEFINE_REGISTER_STUB(r63, "pcl"),
134 DEFINE_GENERIC_REGISTER_STUB(pc, nullptr, LLDB_REGNUM_GENERIC_PC),
135 DEFINE_GENERIC_REGISTER_STUB(status32, nullptr, LLDB_REGNUM_GENERIC_FLAGS)} };
136 } // namespace dwarf
137 } // namespace
138
GetRegisterInfoArray(uint32_t & count)139 const RegisterInfo *ABISysV_arc::GetRegisterInfoArray(uint32_t &count) {
140 count = dwarf::g_register_infos.size();
141 return dwarf::g_register_infos.data();
142 }
143
GetRedZoneSize() const144 size_t ABISysV_arc::GetRedZoneSize() const { return 0; }
145
IsRegisterFileReduced(RegisterContext & reg_ctx) const146 bool ABISysV_arc::IsRegisterFileReduced(RegisterContext ®_ctx) const {
147 if (!m_is_reg_file_reduced) {
148 const auto *const rf_build_reg = reg_ctx.GetRegisterInfoByName("rf_build");
149
150 const auto reg_value = reg_ctx.ReadRegisterAsUnsigned(rf_build_reg,
151 /*fail_value*/ 0);
152 // RF_BUILD "Number of Entries" bit.
153 const uint32_t rf_entries_bit = 1U << 9U;
154 m_is_reg_file_reduced = (reg_value | rf_entries_bit) != 0;
155 }
156
157 return m_is_reg_file_reduced.getValueOr(false);
158 }
159
160 //------------------------------------------------------------------
161 // Static Functions
162 //------------------------------------------------------------------
163
CreateInstance(ProcessSP process_sp,const ArchSpec & arch)164 ABISP ABISysV_arc::CreateInstance(ProcessSP process_sp, const ArchSpec &arch) {
165 return llvm::Triple::arc == arch.GetTriple().getArch() ?
166 ABISP(new ABISysV_arc(std::move(process_sp), MakeMCRegisterInfo(arch))) :
167 ABISP();
168 }
169
170 namespace {
171 const size_t word_size = 4U;
172 const size_t reg_size = word_size;
173
AugmentArgSize(size_t size_in_bytes)174 inline size_t AugmentArgSize(size_t size_in_bytes) {
175 return llvm::alignTo(size_in_bytes, word_size);
176 }
177
TotalArgsSizeInWords(const llvm::ArrayRef<ABI::CallArgument> & args)178 size_t TotalArgsSizeInWords(const llvm::ArrayRef<ABI::CallArgument> &args) {
179 size_t total_size = 0;
180 for (const auto &arg : args)
181 total_size +=
182 (ABI::CallArgument::TargetValue == arg.type ? AugmentArgSize(arg.size)
183 : reg_size) /
184 word_size;
185
186 return total_size;
187 }
188 } // namespace
189
PrepareTrivialCall(Thread & thread,addr_t sp,addr_t func_addr,addr_t return_addr,llvm::ArrayRef<addr_t> args) const190 bool ABISysV_arc::PrepareTrivialCall(Thread &thread, addr_t sp,
191 addr_t func_addr, addr_t return_addr,
192 llvm::ArrayRef<addr_t> args) const {
193 // We don't use the traditional trivial call specialized for jit.
194 return false;
195 }
196
PrepareTrivialCall(Thread & thread,addr_t sp,addr_t pc,addr_t ra,llvm::Type & prototype,llvm::ArrayRef<ABI::CallArgument> args) const197 bool ABISysV_arc::PrepareTrivialCall(Thread &thread, addr_t sp, addr_t pc,
198 addr_t ra, llvm::Type &prototype,
199 llvm::ArrayRef<ABI::CallArgument> args) const {
200 auto reg_ctx = thread.GetRegisterContext();
201 if (!reg_ctx)
202 return false;
203
204 uint32_t pc_reg = reg_ctx->ConvertRegisterKindToRegisterNumber(
205 eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC);
206 if (pc_reg == LLDB_INVALID_REGNUM)
207 return false;
208
209 uint32_t ra_reg = reg_ctx->ConvertRegisterKindToRegisterNumber(
210 eRegisterKindGeneric, LLDB_REGNUM_GENERIC_RA);
211 if (ra_reg == LLDB_INVALID_REGNUM)
212 return false;
213
214 uint32_t sp_reg = reg_ctx->ConvertRegisterKindToRegisterNumber(
215 eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP);
216 if (sp_reg == LLDB_INVALID_REGNUM)
217 return false;
218
219 Status error;
220 ProcessSP process = thread.GetProcess();
221 if (!process)
222 return false;
223
224 // Push host data onto target.
225 for (const auto &arg : args) {
226 // Skip over target values.
227 if (arg.type == ABI::CallArgument::TargetValue)
228 continue;
229
230 // Create space on the stack for this data 4-byte aligned.
231 sp -= AugmentArgSize(arg.size);
232
233 if (process->WriteMemory(sp, arg.data_up.get(), arg.size, error) < arg.size
234 || error.Fail())
235 return false;
236
237 // Update the argument with the target pointer.
238 *const_cast<addr_t *>(&arg.value) = sp;
239 }
240
241 // Make sure number of parameters matches prototype.
242 assert(!prototype.isFunctionVarArg());
243 assert(prototype.getFunctionNumParams() == args.size());
244
245 const size_t regs_for_args_count = IsRegisterFileReduced(*reg_ctx) ? 4U : 8U;
246
247 // Number of arguments passed on stack.
248 auto args_size = TotalArgsSizeInWords(args);
249 auto on_stack =
250 args_size <= regs_for_args_count ? 0 : args_size - regs_for_args_count;
251 auto offset = on_stack * word_size;
252
253 uint8_t reg_value[reg_size];
254 size_t reg_index = LLDB_REGNUM_GENERIC_ARG1;
255
256 for (const auto &arg : args) {
257 auto value = reinterpret_cast<const uint8_t *>(&arg.value);
258 auto size =
259 ABI::CallArgument::TargetValue == arg.type ? arg.size : reg_size;
260
261 // Pass arguments via registers.
262 while (size > 0 && reg_index < regs_for_args_count) {
263 size_t byte_index = 0;
264 auto end = size < reg_size ? size : reg_size;
265
266 while (byte_index < end) {
267 reg_value[byte_index++] = *(value++);
268 --size;
269 }
270
271 while (byte_index < reg_size) {
272 reg_value[byte_index++] = 0;
273 }
274
275 RegisterValue reg_val_obj(llvm::makeArrayRef(reg_value, reg_size),
276 eByteOrderLittle);
277 if (!reg_ctx->WriteRegister(
278 reg_ctx->GetRegisterInfo(eRegisterKindGeneric, reg_index),
279 reg_val_obj))
280 return false;
281
282 // NOTE: It's unsafe to iterate through LLDB_REGNUM_GENERICs.
283 ++reg_index;
284 }
285
286 if (reg_index < regs_for_args_count || size == 0)
287 continue;
288
289 // Remaining arguments are passed on the stack.
290 if (process->WriteMemory(sp - offset, value, size, error) < size ||
291 !error.Success())
292 return false;
293
294 offset -= AugmentArgSize(size);
295 }
296
297 // Set stack pointer immediately below arguments.
298 sp -= on_stack * word_size;
299
300 // Update registers with current function call state.
301 reg_ctx->WriteRegisterFromUnsigned(pc_reg, pc);
302 reg_ctx->WriteRegisterFromUnsigned(ra_reg, ra);
303 reg_ctx->WriteRegisterFromUnsigned(sp_reg, sp);
304
305 return true;
306 }
307
GetArgumentValues(Thread & thread,ValueList & values) const308 bool ABISysV_arc::GetArgumentValues(Thread &thread, ValueList &values) const {
309 return false;
310 }
311
SetReturnValueObject(StackFrameSP & frame_sp,ValueObjectSP & new_value_sp)312 Status ABISysV_arc::SetReturnValueObject(StackFrameSP &frame_sp,
313 ValueObjectSP &new_value_sp) {
314 Status result;
315 if (!new_value_sp) {
316 result.SetErrorString("Empty value object for return value.");
317 return result;
318 }
319
320 CompilerType compiler_type = new_value_sp->GetCompilerType();
321 if (!compiler_type) {
322 result.SetErrorString("Null clang type for return value.");
323 return result;
324 }
325
326 auto ®_ctx = *frame_sp->GetThread()->GetRegisterContext();
327
328 bool is_signed = false;
329 if (!compiler_type.IsIntegerOrEnumerationType(is_signed) &&
330 !compiler_type.IsPointerType()) {
331 result.SetErrorString("We don't support returning other types at present");
332 return result;
333 }
334
335 DataExtractor data;
336 size_t num_bytes = new_value_sp->GetData(data, result);
337
338 if (result.Fail()) {
339 result.SetErrorStringWithFormat(
340 "Couldn't convert return value to raw data: %s", result.AsCString());
341 return result;
342 }
343
344 if (num_bytes <= 2 * reg_size) {
345 offset_t offset = 0;
346 uint64_t raw_value = data.GetMaxU64(&offset, num_bytes);
347
348 auto reg_info =
349 reg_ctx.GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG1);
350 if (!reg_ctx.WriteRegisterFromUnsigned(reg_info, raw_value)) {
351 result.SetErrorStringWithFormat("Couldn't write value to register %s",
352 reg_info->name);
353 return result;
354 }
355
356 if (num_bytes <= reg_size)
357 return result; // Successfully written.
358
359 raw_value >>= 32;
360 reg_info =
361 reg_ctx.GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG2);
362 if (!reg_ctx.WriteRegisterFromUnsigned(reg_info, raw_value)) {
363 result.SetErrorStringWithFormat("Couldn't write value to register %s",
364 reg_info->name);
365 }
366
367 return result;
368 }
369
370 result.SetErrorString(
371 "We don't support returning large integer values at present.");
372 return result;
373 }
374
375 namespace {
376 template <typename T>
SetInteger(Scalar & scalar,uint64_t raw_value,bool is_signed)377 void SetInteger(Scalar &scalar, uint64_t raw_value, bool is_signed) {
378 raw_value &= std::numeric_limits<T>::max();
379 if (is_signed)
380 scalar = static_cast<typename std::make_signed<T>::type>(raw_value);
381 else
382 scalar = static_cast<T>(raw_value);
383 }
384
SetSizedInteger(Scalar & scalar,uint64_t raw_value,uint8_t size_in_bytes,bool is_signed)385 bool SetSizedInteger(Scalar &scalar, uint64_t raw_value, uint8_t size_in_bytes,
386 bool is_signed) {
387 switch (size_in_bytes) {
388 default:
389 return false;
390
391 case sizeof(uint64_t):
392 SetInteger<uint64_t>(scalar, raw_value, is_signed);
393 break;
394
395 case sizeof(uint32_t):
396 SetInteger<uint32_t>(scalar, raw_value, is_signed);
397 break;
398
399 case sizeof(uint16_t):
400 SetInteger<uint16_t>(scalar, raw_value, is_signed);
401 break;
402
403 case sizeof(uint8_t):
404 SetInteger<uint8_t>(scalar, raw_value, is_signed);
405 break;
406 }
407
408 return true;
409 }
410
SetSizedFloat(Scalar & scalar,uint64_t raw_value,uint8_t size_in_bytes)411 bool SetSizedFloat(Scalar &scalar, uint64_t raw_value, uint8_t size_in_bytes) {
412 switch (size_in_bytes) {
413 default:
414 return false;
415
416 case sizeof(uint64_t):
417 scalar = *reinterpret_cast<double *>(&raw_value);
418 break;
419
420 case sizeof(uint32_t):
421 scalar = *reinterpret_cast<float *>(&raw_value);
422 break;
423 }
424
425 return true;
426 }
427
ReadRawValue(const RegisterContextSP & reg_ctx,uint8_t size_in_bytes)428 uint64_t ReadRawValue(const RegisterContextSP ®_ctx, uint8_t size_in_bytes) {
429 auto reg_info_r0 =
430 reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG1);
431
432 // Extract the register context so we can read arguments from registers.
433 uint64_t raw_value =
434 reg_ctx->ReadRegisterAsUnsigned(reg_info_r0, 0) & UINT32_MAX;
435
436 if (sizeof(uint64_t) == size_in_bytes)
437 raw_value |= (reg_ctx->ReadRegisterAsUnsigned(
438 reg_ctx->GetRegisterInfo(eRegisterKindGeneric,
439 LLDB_REGNUM_GENERIC_ARG2), 0) &
440 UINT64_MAX) << 32U;
441
442 return raw_value;
443 }
444 } // namespace
445
446 ValueObjectSP
GetReturnValueObjectSimple(Thread & thread,CompilerType & compiler_type) const447 ABISysV_arc::GetReturnValueObjectSimple(Thread &thread,
448 CompilerType &compiler_type) const {
449 if (!compiler_type)
450 return ValueObjectSP();
451
452 auto reg_ctx = thread.GetRegisterContext();
453 if (!reg_ctx)
454 return ValueObjectSP();
455
456 Value value;
457 value.SetCompilerType(compiler_type);
458
459 const uint32_t type_flags = compiler_type.GetTypeInfo();
460 // Integer return type.
461 if (type_flags & eTypeIsInteger) {
462 const size_t byte_size = compiler_type.GetByteSize(&thread).getValueOr(0);
463 auto raw_value = ReadRawValue(reg_ctx, byte_size);
464
465 const bool is_signed = (type_flags & eTypeIsSigned) != 0;
466 if (!SetSizedInteger(value.GetScalar(), raw_value, byte_size, is_signed))
467 return ValueObjectSP();
468
469 value.SetValueType(Value::ValueType::Scalar);
470 }
471 // Pointer return type.
472 else if (type_flags & eTypeIsPointer) {
473 auto reg_info_r0 = reg_ctx->GetRegisterInfo(eRegisterKindGeneric,
474 LLDB_REGNUM_GENERIC_ARG1);
475 value.GetScalar() = reg_ctx->ReadRegisterAsUnsigned(reg_info_r0, 0);
476
477 value.SetValueType(Value::ValueType::Scalar);
478 }
479 // Floating point return type.
480 else if (type_flags & eTypeIsFloat) {
481 uint32_t float_count = 0;
482 bool is_complex = false;
483
484 if (compiler_type.IsFloatingPointType(float_count, is_complex) &&
485 1 == float_count && !is_complex) {
486 const size_t byte_size = compiler_type.GetByteSize(&thread).getValueOr(0);
487 auto raw_value = ReadRawValue(reg_ctx, byte_size);
488
489 if (!SetSizedFloat(value.GetScalar(), raw_value, byte_size))
490 return ValueObjectSP();
491 }
492 }
493 // Unsupported return type.
494 else
495 return ValueObjectSP();
496
497 return ValueObjectConstResult::Create(thread.GetStackFrameAtIndex(0).get(),
498 value, ConstString(""));
499 }
500
GetReturnValueObjectImpl(Thread & thread,CompilerType & return_compiler_type) const501 ValueObjectSP ABISysV_arc::GetReturnValueObjectImpl(
502 Thread &thread, CompilerType &return_compiler_type) const {
503 ValueObjectSP return_valobj_sp;
504
505 if (!return_compiler_type)
506 return return_valobj_sp;
507
508 ExecutionContext exe_ctx(thread.shared_from_this());
509 return GetReturnValueObjectSimple(thread, return_compiler_type);
510 }
511
GetReturnValueObjectImpl(Thread & thread,llvm::Type & retType) const512 ValueObjectSP ABISysV_arc::GetReturnValueObjectImpl(Thread &thread,
513 llvm::Type &retType) const {
514 auto reg_ctx = thread.GetRegisterContext();
515 if (!reg_ctx)
516 return ValueObjectSP();
517
518 Value value;
519 // Void return type.
520 if (retType.isVoidTy()) {
521 value.GetScalar() = 0;
522 }
523 // Integer return type.
524 else if (retType.isIntegerTy()) {
525 size_t byte_size = retType.getPrimitiveSizeInBits();
526 if (1 != byte_size) // For boolean type.
527 byte_size /= CHAR_BIT;
528
529 auto raw_value = ReadRawValue(reg_ctx, byte_size);
530
531 const bool is_signed = false; // IR Type doesn't provide this info.
532 if (!SetSizedInteger(value.GetScalar(), raw_value, byte_size, is_signed))
533 return ValueObjectSP();
534 }
535 // Pointer return type.
536 else if (retType.isPointerTy()) {
537 auto reg_info_r0 = reg_ctx->GetRegisterInfo(eRegisterKindGeneric,
538 LLDB_REGNUM_GENERIC_ARG1);
539 value.GetScalar() = reg_ctx->ReadRegisterAsUnsigned(reg_info_r0, 0);
540 value.SetValueType(Value::ValueType::Scalar);
541 }
542 // Floating point return type.
543 else if (retType.isFloatingPointTy()) {
544 const size_t byte_size = retType.getPrimitiveSizeInBits() / CHAR_BIT;
545 auto raw_value = ReadRawValue(reg_ctx, byte_size);
546
547 if (!SetSizedFloat(value.GetScalar(), raw_value, byte_size))
548 return ValueObjectSP();
549 }
550 // Unsupported return type.
551 else
552 return ValueObjectSP();
553
554 return ValueObjectConstResult::Create(thread.GetStackFrameAtIndex(0).get(),
555 value, ConstString(""));
556 }
557
CreateFunctionEntryUnwindPlan(UnwindPlan & unwind_plan)558 bool ABISysV_arc::CreateFunctionEntryUnwindPlan(UnwindPlan &unwind_plan) {
559 unwind_plan.Clear();
560 unwind_plan.SetRegisterKind(eRegisterKindDWARF);
561
562 UnwindPlan::RowSP row(new UnwindPlan::Row);
563
564 // Our Call Frame Address is the stack pointer value.
565 row->GetCFAValue().SetIsRegisterPlusOffset(dwarf::sp, 0);
566
567 // The previous PC is in the BLINK.
568 row->SetRegisterLocationToRegister(dwarf::pc, dwarf::blink, true);
569 unwind_plan.AppendRow(row);
570
571 // All other registers are the same.
572 unwind_plan.SetSourceName("arc at-func-entry default");
573 unwind_plan.SetSourcedFromCompiler(eLazyBoolNo);
574
575 return true;
576 }
577
CreateDefaultUnwindPlan(UnwindPlan & unwind_plan)578 bool ABISysV_arc::CreateDefaultUnwindPlan(UnwindPlan &unwind_plan) {
579 return false;
580 }
581
RegisterIsVolatile(const RegisterInfo * reg_info)582 bool ABISysV_arc::RegisterIsVolatile(const RegisterInfo *reg_info) {
583 if (nullptr == reg_info)
584 return false;
585
586 // Volatile registers are: r0..r12.
587 uint32_t regnum = reg_info->kinds[eRegisterKindDWARF];
588 if (regnum <= 12)
589 return true;
590
591 static const std::string ra_reg_name = "blink";
592 return ra_reg_name == reg_info->name;
593 }
594
Initialize()595 void ABISysV_arc::Initialize() {
596 PluginManager::RegisterPlugin(GetPluginNameStatic(),
597 "System V ABI for ARC targets", CreateInstance);
598 }
599
Terminate()600 void ABISysV_arc::Terminate() {
601 PluginManager::UnregisterPlugin(CreateInstance);
602 }
603
GetPluginNameStatic()604 ConstString ABISysV_arc::GetPluginNameStatic() {
605 static ConstString g_name("sysv-arc");
606 return g_name;
607 }
608
609 //------------------------------------------------------------------
610 // PluginInterface protocol
611 //------------------------------------------------------------------
612
GetPluginName()613 ConstString ABISysV_arc::GetPluginName() {
614 return GetPluginNameStatic();
615 }
616
GetPluginVersion()617 uint32_t ABISysV_arc::GetPluginVersion() { return 1; }
618