1 //===-- ABISysV_ppc.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_ppc.h"
10
11 #include "llvm/ADT/STLExtras.h"
12 #include "llvm/ADT/Triple.h"
13
14 #include "lldb/Core/Module.h"
15 #include "lldb/Core/PluginManager.h"
16 #include "lldb/Core/Value.h"
17 #include "lldb/Core/ValueObjectConstResult.h"
18 #include "lldb/Core/ValueObjectMemory.h"
19 #include "lldb/Core/ValueObjectRegister.h"
20 #include "lldb/Symbol/UnwindPlan.h"
21 #include "lldb/Target/Process.h"
22 #include "lldb/Target/RegisterContext.h"
23 #include "lldb/Target/StackFrame.h"
24 #include "lldb/Target/Target.h"
25 #include "lldb/Target/Thread.h"
26 #include "lldb/Utility/ConstString.h"
27 #include "lldb/Utility/DataExtractor.h"
28 #include "lldb/Utility/LLDBLog.h"
29 #include "lldb/Utility/Log.h"
30 #include "lldb/Utility/RegisterValue.h"
31 #include "lldb/Utility/Status.h"
32 #include <optional>
33
34 using namespace lldb;
35 using namespace lldb_private;
36
37 LLDB_PLUGIN_DEFINE(ABISysV_ppc)
38
39 enum dwarf_regnums {
40 dwarf_r0 = 0,
41 dwarf_r1,
42 dwarf_r2,
43 dwarf_r3,
44 dwarf_r4,
45 dwarf_r5,
46 dwarf_r6,
47 dwarf_r7,
48 dwarf_r8,
49 dwarf_r9,
50 dwarf_r10,
51 dwarf_r11,
52 dwarf_r12,
53 dwarf_r13,
54 dwarf_r14,
55 dwarf_r15,
56 dwarf_r16,
57 dwarf_r17,
58 dwarf_r18,
59 dwarf_r19,
60 dwarf_r20,
61 dwarf_r21,
62 dwarf_r22,
63 dwarf_r23,
64 dwarf_r24,
65 dwarf_r25,
66 dwarf_r26,
67 dwarf_r27,
68 dwarf_r28,
69 dwarf_r29,
70 dwarf_r30,
71 dwarf_r31,
72 dwarf_f0,
73 dwarf_f1,
74 dwarf_f2,
75 dwarf_f3,
76 dwarf_f4,
77 dwarf_f5,
78 dwarf_f6,
79 dwarf_f7,
80 dwarf_f8,
81 dwarf_f9,
82 dwarf_f10,
83 dwarf_f11,
84 dwarf_f12,
85 dwarf_f13,
86 dwarf_f14,
87 dwarf_f15,
88 dwarf_f16,
89 dwarf_f17,
90 dwarf_f18,
91 dwarf_f19,
92 dwarf_f20,
93 dwarf_f21,
94 dwarf_f22,
95 dwarf_f23,
96 dwarf_f24,
97 dwarf_f25,
98 dwarf_f26,
99 dwarf_f27,
100 dwarf_f28,
101 dwarf_f29,
102 dwarf_f30,
103 dwarf_f31,
104 dwarf_cr,
105 dwarf_fpscr,
106 dwarf_xer = 101,
107 dwarf_lr = 108,
108 dwarf_ctr,
109 dwarf_pc,
110 dwarf_cfa,
111 };
112
113 // Note that the size and offset will be updated by platform-specific classes.
114 #define DEFINE_GPR(reg, alt, kind1, kind2, kind3, kind4) \
115 { \
116 #reg, alt, 8, 0, eEncodingUint, eFormatHex, {kind1, kind2, kind3, kind4 }, \
117 nullptr, nullptr, \
118 }
119
120 static const RegisterInfo g_register_infos[] = {
121 // General purpose registers. eh_frame, DWARF,
122 // Generic, Process Plugin
123 DEFINE_GPR(r0, nullptr, dwarf_r0, dwarf_r0, LLDB_INVALID_REGNUM,
124 LLDB_INVALID_REGNUM),
125 DEFINE_GPR(r1, nullptr, dwarf_r1, dwarf_r1, LLDB_REGNUM_GENERIC_SP,
126 LLDB_INVALID_REGNUM),
127 DEFINE_GPR(r2, nullptr, dwarf_r2, dwarf_r2, LLDB_INVALID_REGNUM,
128 LLDB_INVALID_REGNUM),
129 DEFINE_GPR(r3, nullptr, dwarf_r3, dwarf_r3, LLDB_REGNUM_GENERIC_ARG1,
130 LLDB_INVALID_REGNUM),
131 DEFINE_GPR(r4, nullptr, dwarf_r4, dwarf_r4, LLDB_REGNUM_GENERIC_ARG2,
132 LLDB_INVALID_REGNUM),
133 DEFINE_GPR(r5, nullptr, dwarf_r5, dwarf_r5, LLDB_REGNUM_GENERIC_ARG3,
134 LLDB_INVALID_REGNUM),
135 DEFINE_GPR(r6, nullptr, dwarf_r6, dwarf_r6, LLDB_REGNUM_GENERIC_ARG4,
136 LLDB_INVALID_REGNUM),
137 DEFINE_GPR(r7, nullptr, dwarf_r7, dwarf_r7, LLDB_REGNUM_GENERIC_ARG5,
138 LLDB_INVALID_REGNUM),
139 DEFINE_GPR(r8, nullptr, dwarf_r8, dwarf_r8, LLDB_REGNUM_GENERIC_ARG6,
140 LLDB_INVALID_REGNUM),
141 DEFINE_GPR(r9, nullptr, dwarf_r9, dwarf_r9, LLDB_REGNUM_GENERIC_ARG7,
142 LLDB_INVALID_REGNUM),
143 DEFINE_GPR(r10, nullptr, dwarf_r10, dwarf_r10, LLDB_REGNUM_GENERIC_ARG8,
144 LLDB_INVALID_REGNUM),
145 DEFINE_GPR(r11, nullptr, dwarf_r11, dwarf_r11, LLDB_INVALID_REGNUM,
146 LLDB_INVALID_REGNUM),
147 DEFINE_GPR(r12, nullptr, dwarf_r12, dwarf_r12, LLDB_INVALID_REGNUM,
148 LLDB_INVALID_REGNUM),
149 DEFINE_GPR(r13, nullptr, dwarf_r13, dwarf_r13, LLDB_INVALID_REGNUM,
150 LLDB_INVALID_REGNUM),
151 DEFINE_GPR(r14, nullptr, dwarf_r14, dwarf_r14, LLDB_INVALID_REGNUM,
152 LLDB_INVALID_REGNUM),
153 DEFINE_GPR(r15, nullptr, dwarf_r15, dwarf_r15, LLDB_INVALID_REGNUM,
154 LLDB_INVALID_REGNUM),
155 DEFINE_GPR(r16, nullptr, dwarf_r16, dwarf_r16, LLDB_INVALID_REGNUM,
156 LLDB_INVALID_REGNUM),
157 DEFINE_GPR(r17, nullptr, dwarf_r17, dwarf_r17, LLDB_INVALID_REGNUM,
158 LLDB_INVALID_REGNUM),
159 DEFINE_GPR(r18, nullptr, dwarf_r18, dwarf_r18, LLDB_INVALID_REGNUM,
160 LLDB_INVALID_REGNUM),
161 DEFINE_GPR(r19, nullptr, dwarf_r19, dwarf_r19, LLDB_INVALID_REGNUM,
162 LLDB_INVALID_REGNUM),
163 DEFINE_GPR(r20, nullptr, dwarf_r20, dwarf_r20, LLDB_INVALID_REGNUM,
164 LLDB_INVALID_REGNUM),
165 DEFINE_GPR(r21, nullptr, dwarf_r21, dwarf_r21, LLDB_INVALID_REGNUM,
166 LLDB_INVALID_REGNUM),
167 DEFINE_GPR(r22, nullptr, dwarf_r22, dwarf_r22, LLDB_INVALID_REGNUM,
168 LLDB_INVALID_REGNUM),
169 DEFINE_GPR(r23, nullptr, dwarf_r23, dwarf_r23, LLDB_INVALID_REGNUM,
170 LLDB_INVALID_REGNUM),
171 DEFINE_GPR(r24, nullptr, dwarf_r24, dwarf_r24, LLDB_INVALID_REGNUM,
172 LLDB_INVALID_REGNUM),
173 DEFINE_GPR(r25, nullptr, dwarf_r25, dwarf_r25, LLDB_INVALID_REGNUM,
174 LLDB_INVALID_REGNUM),
175 DEFINE_GPR(r26, nullptr, dwarf_r26, dwarf_r26, LLDB_INVALID_REGNUM,
176 LLDB_INVALID_REGNUM),
177 DEFINE_GPR(r27, nullptr, dwarf_r27, dwarf_r27, LLDB_INVALID_REGNUM,
178 LLDB_INVALID_REGNUM),
179 DEFINE_GPR(r28, nullptr, dwarf_r28, dwarf_r28, LLDB_INVALID_REGNUM,
180 LLDB_INVALID_REGNUM),
181 DEFINE_GPR(r29, nullptr, dwarf_r29, dwarf_r29, LLDB_INVALID_REGNUM,
182 LLDB_INVALID_REGNUM),
183 DEFINE_GPR(r30, nullptr, dwarf_r30, dwarf_r30, LLDB_INVALID_REGNUM,
184 LLDB_INVALID_REGNUM),
185 DEFINE_GPR(r31, nullptr, dwarf_r31, dwarf_r31, LLDB_INVALID_REGNUM,
186 LLDB_INVALID_REGNUM),
187 DEFINE_GPR(lr, nullptr, dwarf_lr, dwarf_lr, LLDB_REGNUM_GENERIC_RA,
188 LLDB_INVALID_REGNUM),
189 DEFINE_GPR(cr, nullptr, dwarf_cr, dwarf_cr, LLDB_REGNUM_GENERIC_FLAGS,
190 LLDB_INVALID_REGNUM),
191 DEFINE_GPR(xer, nullptr, dwarf_xer, dwarf_xer, LLDB_INVALID_REGNUM,
192 LLDB_INVALID_REGNUM),
193 DEFINE_GPR(ctr, nullptr, dwarf_ctr, dwarf_ctr, LLDB_INVALID_REGNUM,
194 LLDB_INVALID_REGNUM),
195 DEFINE_GPR(pc, nullptr, dwarf_pc, dwarf_pc, LLDB_REGNUM_GENERIC_PC,
196 LLDB_INVALID_REGNUM),
197 {nullptr,
198 nullptr,
199 8,
200 0,
201 eEncodingUint,
202 eFormatHex,
203 {dwarf_cfa, dwarf_cfa, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM},
204 nullptr,
205 nullptr,
206 }};
207
208 static const uint32_t k_num_register_infos = std::size(g_register_infos);
209
210 const lldb_private::RegisterInfo *
GetRegisterInfoArray(uint32_t & count)211 ABISysV_ppc::GetRegisterInfoArray(uint32_t &count) {
212 count = k_num_register_infos;
213 return g_register_infos;
214 }
215
GetRedZoneSize() const216 size_t ABISysV_ppc::GetRedZoneSize() const { return 224; }
217
218 // Static Functions
219
220 ABISP
CreateInstance(lldb::ProcessSP process_sp,const ArchSpec & arch)221 ABISysV_ppc::CreateInstance(lldb::ProcessSP process_sp, const ArchSpec &arch) {
222 if (arch.GetTriple().getArch() == llvm::Triple::ppc) {
223 return ABISP(
224 new ABISysV_ppc(std::move(process_sp), MakeMCRegisterInfo(arch)));
225 }
226 return ABISP();
227 }
228
PrepareTrivialCall(Thread & thread,addr_t sp,addr_t func_addr,addr_t return_addr,llvm::ArrayRef<addr_t> args) const229 bool ABISysV_ppc::PrepareTrivialCall(Thread &thread, addr_t sp,
230 addr_t func_addr, addr_t return_addr,
231 llvm::ArrayRef<addr_t> args) const {
232 Log *log = GetLog(LLDBLog::Expressions);
233
234 if (log) {
235 StreamString s;
236 s.Printf("ABISysV_ppc::PrepareTrivialCall (tid = 0x%" PRIx64
237 ", sp = 0x%" PRIx64 ", func_addr = 0x%" PRIx64
238 ", return_addr = 0x%" PRIx64,
239 thread.GetID(), (uint64_t)sp, (uint64_t)func_addr,
240 (uint64_t)return_addr);
241
242 for (size_t i = 0; i < args.size(); ++i)
243 s.Printf(", arg%" PRIu64 " = 0x%" PRIx64, static_cast<uint64_t>(i + 1),
244 args[i]);
245 s.PutCString(")");
246 log->PutString(s.GetString());
247 }
248
249 RegisterContext *reg_ctx = thread.GetRegisterContext().get();
250 if (!reg_ctx)
251 return false;
252
253 const RegisterInfo *reg_info = nullptr;
254
255 if (args.size() > 8) // TODO handle more than 8 arguments
256 return false;
257
258 for (size_t i = 0; i < args.size(); ++i) {
259 reg_info = reg_ctx->GetRegisterInfo(eRegisterKindGeneric,
260 LLDB_REGNUM_GENERIC_ARG1 + i);
261 LLDB_LOGF(log, "About to write arg%" PRIu64 " (0x%" PRIx64 ") into %s",
262 static_cast<uint64_t>(i + 1), args[i], reg_info->name);
263 if (!reg_ctx->WriteRegisterFromUnsigned(reg_info, args[i]))
264 return false;
265 }
266
267 // First, align the SP
268
269 LLDB_LOGF(log, "16-byte aligning SP: 0x%" PRIx64 " to 0x%" PRIx64,
270 (uint64_t)sp, (uint64_t)(sp & ~0xfull));
271
272 sp &= ~(0xfull); // 16-byte alignment
273
274 sp -= 8;
275
276 Status error;
277 const RegisterInfo *pc_reg_info =
278 reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC);
279 const RegisterInfo *sp_reg_info =
280 reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP);
281 ProcessSP process_sp(thread.GetProcess());
282
283 RegisterValue reg_value;
284
285 LLDB_LOGF(log,
286 "Pushing the return address onto the stack: 0x%" PRIx64
287 ": 0x%" PRIx64,
288 (uint64_t)sp, (uint64_t)return_addr);
289
290 // Save return address onto the stack
291 if (!process_sp->WritePointerToMemory(sp, return_addr, error))
292 return false;
293
294 // %r1 is set to the actual stack value.
295
296 LLDB_LOGF(log, "Writing SP: 0x%" PRIx64, (uint64_t)sp);
297
298 if (!reg_ctx->WriteRegisterFromUnsigned(sp_reg_info, sp))
299 return false;
300
301 // %pc is set to the address of the called function.
302
303 LLDB_LOGF(log, "Writing IP: 0x%" PRIx64, (uint64_t)func_addr);
304
305 if (!reg_ctx->WriteRegisterFromUnsigned(pc_reg_info, func_addr))
306 return false;
307
308 return true;
309 }
310
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)311 static bool ReadIntegerArgument(Scalar &scalar, unsigned int bit_width,
312 bool is_signed, Thread &thread,
313 uint32_t *argument_register_ids,
314 unsigned int ¤t_argument_register,
315 addr_t ¤t_stack_argument) {
316 if (bit_width > 64)
317 return false; // Scalar can't hold large integer arguments
318
319 if (current_argument_register < 6) {
320 scalar = thread.GetRegisterContext()->ReadRegisterAsUnsigned(
321 argument_register_ids[current_argument_register], 0);
322 current_argument_register++;
323 if (is_signed)
324 scalar.SignExtend(bit_width);
325 } else {
326 uint32_t byte_size = (bit_width + (8 - 1)) / 8;
327 Status error;
328 if (thread.GetProcess()->ReadScalarIntegerFromMemory(
329 current_stack_argument, byte_size, is_signed, scalar, error)) {
330 current_stack_argument += byte_size;
331 return true;
332 }
333 return false;
334 }
335 return true;
336 }
337
GetArgumentValues(Thread & thread,ValueList & values) const338 bool ABISysV_ppc::GetArgumentValues(Thread &thread, ValueList &values) const {
339 unsigned int num_values = values.GetSize();
340 unsigned int value_index;
341
342 // Extract the register context so we can read arguments from registers
343
344 RegisterContext *reg_ctx = thread.GetRegisterContext().get();
345
346 if (!reg_ctx)
347 return false;
348
349 // Get the pointer to the first stack argument so we have a place to start
350 // when reading data
351
352 addr_t sp = reg_ctx->GetSP(0);
353
354 if (!sp)
355 return false;
356
357 addr_t current_stack_argument = sp + 48; // jump over return address
358
359 uint32_t argument_register_ids[8];
360
361 argument_register_ids[0] =
362 reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG1)
363 ->kinds[eRegisterKindLLDB];
364 argument_register_ids[1] =
365 reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG2)
366 ->kinds[eRegisterKindLLDB];
367 argument_register_ids[2] =
368 reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG3)
369 ->kinds[eRegisterKindLLDB];
370 argument_register_ids[3] =
371 reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG4)
372 ->kinds[eRegisterKindLLDB];
373 argument_register_ids[4] =
374 reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG5)
375 ->kinds[eRegisterKindLLDB];
376 argument_register_ids[5] =
377 reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG6)
378 ->kinds[eRegisterKindLLDB];
379 argument_register_ids[6] =
380 reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG7)
381 ->kinds[eRegisterKindLLDB];
382 argument_register_ids[7] =
383 reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG8)
384 ->kinds[eRegisterKindLLDB];
385
386 unsigned int current_argument_register = 0;
387
388 for (value_index = 0; value_index < num_values; ++value_index) {
389 Value *value = values.GetValueAtIndex(value_index);
390
391 if (!value)
392 return false;
393
394 // We currently only support extracting values with Clang QualTypes. Do we
395 // care about others?
396 CompilerType compiler_type = value->GetCompilerType();
397 std::optional<uint64_t> bit_size = compiler_type.GetBitSize(&thread);
398 if (!bit_size)
399 return false;
400 bool is_signed;
401 if (compiler_type.IsIntegerOrEnumerationType(is_signed))
402 ReadIntegerArgument(value->GetScalar(), *bit_size, is_signed, thread,
403 argument_register_ids, current_argument_register,
404 current_stack_argument);
405 else if (compiler_type.IsPointerType())
406 ReadIntegerArgument(value->GetScalar(), *bit_size, false, thread,
407 argument_register_ids, current_argument_register,
408 current_stack_argument);
409 }
410
411 return true;
412 }
413
SetReturnValueObject(lldb::StackFrameSP & frame_sp,lldb::ValueObjectSP & new_value_sp)414 Status ABISysV_ppc::SetReturnValueObject(lldb::StackFrameSP &frame_sp,
415 lldb::ValueObjectSP &new_value_sp) {
416 Status error;
417 if (!new_value_sp) {
418 error.SetErrorString("Empty value object for return value.");
419 return error;
420 }
421
422 CompilerType compiler_type = new_value_sp->GetCompilerType();
423 if (!compiler_type) {
424 error.SetErrorString("Null clang type for return value.");
425 return error;
426 }
427
428 Thread *thread = frame_sp->GetThread().get();
429
430 bool is_signed;
431 uint32_t count;
432 bool is_complex;
433
434 RegisterContext *reg_ctx = thread->GetRegisterContext().get();
435
436 bool set_it_simple = false;
437 if (compiler_type.IsIntegerOrEnumerationType(is_signed) ||
438 compiler_type.IsPointerType()) {
439 const RegisterInfo *reg_info = reg_ctx->GetRegisterInfoByName("r3", 0);
440
441 DataExtractor data;
442 Status data_error;
443 size_t num_bytes = new_value_sp->GetData(data, data_error);
444 if (data_error.Fail()) {
445 error.SetErrorStringWithFormat(
446 "Couldn't convert return value to raw data: %s",
447 data_error.AsCString());
448 return error;
449 }
450 lldb::offset_t offset = 0;
451 if (num_bytes <= 8) {
452 uint64_t raw_value = data.GetMaxU64(&offset, num_bytes);
453
454 if (reg_ctx->WriteRegisterFromUnsigned(reg_info, raw_value))
455 set_it_simple = true;
456 } else {
457 error.SetErrorString("We don't support returning longer than 64 bit "
458 "integer values at present.");
459 }
460 } else if (compiler_type.IsFloatingPointType(count, is_complex)) {
461 if (is_complex)
462 error.SetErrorString(
463 "We don't support returning complex values at present");
464 else {
465 std::optional<uint64_t> bit_width =
466 compiler_type.GetBitSize(frame_sp.get());
467 if (!bit_width) {
468 error.SetErrorString("can't get type size");
469 return error;
470 }
471 if (*bit_width <= 64) {
472 DataExtractor data;
473 Status data_error;
474 size_t num_bytes = new_value_sp->GetData(data, data_error);
475 if (data_error.Fail()) {
476 error.SetErrorStringWithFormat(
477 "Couldn't convert return value to raw data: %s",
478 data_error.AsCString());
479 return error;
480 }
481
482 unsigned char buffer[16];
483 ByteOrder byte_order = data.GetByteOrder();
484
485 data.CopyByteOrderedData(0, num_bytes, buffer, 16, byte_order);
486 set_it_simple = true;
487 } else {
488 // FIXME - don't know how to do 80 bit long doubles yet.
489 error.SetErrorString(
490 "We don't support returning float values > 64 bits at present");
491 }
492 }
493 }
494
495 if (!set_it_simple) {
496 // Okay we've got a structure or something that doesn't fit in a simple
497 // register. We should figure out where it really goes, but we don't
498 // support this yet.
499 error.SetErrorString("We only support setting simple integer and float "
500 "return types at present.");
501 }
502
503 return error;
504 }
505
GetReturnValueObjectSimple(Thread & thread,CompilerType & return_compiler_type) const506 ValueObjectSP ABISysV_ppc::GetReturnValueObjectSimple(
507 Thread &thread, CompilerType &return_compiler_type) const {
508 ValueObjectSP return_valobj_sp;
509 Value value;
510
511 if (!return_compiler_type)
512 return return_valobj_sp;
513
514 // value.SetContext (Value::eContextTypeClangType, return_value_type);
515 value.SetCompilerType(return_compiler_type);
516
517 RegisterContext *reg_ctx = thread.GetRegisterContext().get();
518 if (!reg_ctx)
519 return return_valobj_sp;
520
521 const uint32_t type_flags = return_compiler_type.GetTypeInfo();
522 if (type_flags & eTypeIsScalar) {
523 value.SetValueType(Value::ValueType::Scalar);
524
525 bool success = false;
526 if (type_flags & eTypeIsInteger) {
527 // Extract the register context so we can read arguments from registers
528
529 std::optional<uint64_t> byte_size =
530 return_compiler_type.GetByteSize(&thread);
531 if (!byte_size)
532 return return_valobj_sp;
533 uint64_t raw_value = thread.GetRegisterContext()->ReadRegisterAsUnsigned(
534 reg_ctx->GetRegisterInfoByName("r3", 0), 0);
535 const bool is_signed = (type_flags & eTypeIsSigned) != 0;
536 switch (*byte_size) {
537 default:
538 break;
539
540 case sizeof(uint64_t):
541 if (is_signed)
542 value.GetScalar() = (int64_t)(raw_value);
543 else
544 value.GetScalar() = (uint64_t)(raw_value);
545 success = true;
546 break;
547
548 case sizeof(uint32_t):
549 if (is_signed)
550 value.GetScalar() = (int32_t)(raw_value & UINT32_MAX);
551 else
552 value.GetScalar() = (uint32_t)(raw_value & UINT32_MAX);
553 success = true;
554 break;
555
556 case sizeof(uint16_t):
557 if (is_signed)
558 value.GetScalar() = (int16_t)(raw_value & UINT16_MAX);
559 else
560 value.GetScalar() = (uint16_t)(raw_value & UINT16_MAX);
561 success = true;
562 break;
563
564 case sizeof(uint8_t):
565 if (is_signed)
566 value.GetScalar() = (int8_t)(raw_value & UINT8_MAX);
567 else
568 value.GetScalar() = (uint8_t)(raw_value & UINT8_MAX);
569 success = true;
570 break;
571 }
572 } else if (type_flags & eTypeIsFloat) {
573 if (type_flags & eTypeIsComplex) {
574 // Don't handle complex yet.
575 } else {
576 std::optional<uint64_t> byte_size =
577 return_compiler_type.GetByteSize(&thread);
578 if (byte_size && *byte_size <= sizeof(long double)) {
579 const RegisterInfo *f1_info = reg_ctx->GetRegisterInfoByName("f1", 0);
580 RegisterValue f1_value;
581 if (reg_ctx->ReadRegister(f1_info, f1_value)) {
582 DataExtractor data;
583 if (f1_value.GetData(data)) {
584 lldb::offset_t offset = 0;
585 if (*byte_size == sizeof(float)) {
586 value.GetScalar() = (float)data.GetFloat(&offset);
587 success = true;
588 } else if (*byte_size == sizeof(double)) {
589 value.GetScalar() = (double)data.GetDouble(&offset);
590 success = true;
591 }
592 }
593 }
594 }
595 }
596 }
597
598 if (success)
599 return_valobj_sp = ValueObjectConstResult::Create(
600 thread.GetStackFrameAtIndex(0).get(), value, ConstString(""));
601 } else if (type_flags & eTypeIsPointer) {
602 unsigned r3_id =
603 reg_ctx->GetRegisterInfoByName("r3", 0)->kinds[eRegisterKindLLDB];
604 value.GetScalar() =
605 (uint64_t)thread.GetRegisterContext()->ReadRegisterAsUnsigned(r3_id, 0);
606 value.SetValueType(Value::ValueType::Scalar);
607 return_valobj_sp = ValueObjectConstResult::Create(
608 thread.GetStackFrameAtIndex(0).get(), value, ConstString(""));
609 } else if (type_flags & eTypeIsVector) {
610 std::optional<uint64_t> byte_size =
611 return_compiler_type.GetByteSize(&thread);
612 if (byte_size && *byte_size > 0) {
613 const RegisterInfo *altivec_reg = reg_ctx->GetRegisterInfoByName("v2", 0);
614 if (altivec_reg) {
615 if (*byte_size <= altivec_reg->byte_size) {
616 ProcessSP process_sp(thread.GetProcess());
617 if (process_sp) {
618 std::unique_ptr<DataBufferHeap> heap_data_up(
619 new DataBufferHeap(*byte_size, 0));
620 const ByteOrder byte_order = process_sp->GetByteOrder();
621 RegisterValue reg_value;
622 if (reg_ctx->ReadRegister(altivec_reg, reg_value)) {
623 Status error;
624 if (reg_value.GetAsMemoryData(
625 *altivec_reg, heap_data_up->GetBytes(),
626 heap_data_up->GetByteSize(), byte_order, error)) {
627 DataExtractor data(DataBufferSP(heap_data_up.release()),
628 byte_order,
629 process_sp->GetTarget()
630 .GetArchitecture()
631 .GetAddressByteSize());
632 return_valobj_sp = ValueObjectConstResult::Create(
633 &thread, return_compiler_type, ConstString(""), data);
634 }
635 }
636 }
637 }
638 }
639 }
640 }
641
642 return return_valobj_sp;
643 }
644
GetReturnValueObjectImpl(Thread & thread,CompilerType & return_compiler_type) const645 ValueObjectSP ABISysV_ppc::GetReturnValueObjectImpl(
646 Thread &thread, CompilerType &return_compiler_type) const {
647 ValueObjectSP return_valobj_sp;
648
649 if (!return_compiler_type)
650 return return_valobj_sp;
651
652 ExecutionContext exe_ctx(thread.shared_from_this());
653 return_valobj_sp = GetReturnValueObjectSimple(thread, return_compiler_type);
654 if (return_valobj_sp)
655 return return_valobj_sp;
656
657 RegisterContextSP reg_ctx_sp = thread.GetRegisterContext();
658 if (!reg_ctx_sp)
659 return return_valobj_sp;
660
661 std::optional<uint64_t> bit_width = return_compiler_type.GetBitSize(&thread);
662 if (!bit_width)
663 return return_valobj_sp;
664 if (return_compiler_type.IsAggregateType()) {
665 Target *target = exe_ctx.GetTargetPtr();
666 bool is_memory = true;
667 if (*bit_width <= 128) {
668 ByteOrder target_byte_order = target->GetArchitecture().GetByteOrder();
669 WritableDataBufferSP data_sp(new DataBufferHeap(16, 0));
670 DataExtractor return_ext(data_sp, target_byte_order,
671 target->GetArchitecture().GetAddressByteSize());
672
673 const RegisterInfo *r3_info = reg_ctx_sp->GetRegisterInfoByName("r3", 0);
674 const RegisterInfo *rdx_info =
675 reg_ctx_sp->GetRegisterInfoByName("rdx", 0);
676
677 RegisterValue r3_value, rdx_value;
678 reg_ctx_sp->ReadRegister(r3_info, r3_value);
679 reg_ctx_sp->ReadRegister(rdx_info, rdx_value);
680
681 DataExtractor r3_data, rdx_data;
682
683 r3_value.GetData(r3_data);
684 rdx_value.GetData(rdx_data);
685
686 uint32_t integer_bytes =
687 0; // Tracks how much of the r3/rds registers we've consumed so far
688
689 const uint32_t num_children = return_compiler_type.GetNumFields();
690
691 // Since we are in the small struct regime, assume we are not in memory.
692 is_memory = false;
693
694 for (uint32_t idx = 0; idx < num_children; idx++) {
695 std::string name;
696 uint64_t field_bit_offset = 0;
697 bool is_signed;
698 bool is_complex;
699 uint32_t count;
700
701 CompilerType field_compiler_type = return_compiler_type.GetFieldAtIndex(
702 idx, name, &field_bit_offset, nullptr, nullptr);
703 std::optional<uint64_t> field_bit_width =
704 field_compiler_type.GetBitSize(&thread);
705 if (!field_bit_width)
706 return return_valobj_sp;
707
708 // If there are any unaligned fields, this is stored in memory.
709 if (field_bit_offset % *field_bit_width != 0) {
710 is_memory = true;
711 break;
712 }
713
714 uint32_t field_byte_width = *field_bit_width / 8;
715 uint32_t field_byte_offset = field_bit_offset / 8;
716
717 DataExtractor *copy_from_extractor = nullptr;
718 uint32_t copy_from_offset = 0;
719
720 if (field_compiler_type.IsIntegerOrEnumerationType(is_signed) ||
721 field_compiler_type.IsPointerType()) {
722 if (integer_bytes < 8) {
723 if (integer_bytes + field_byte_width <= 8) {
724 // This is in RAX, copy from register to our result structure:
725 copy_from_extractor = &r3_data;
726 copy_from_offset = integer_bytes;
727 integer_bytes += field_byte_width;
728 } else {
729 // The next field wouldn't fit in the remaining space, so we
730 // pushed it to rdx.
731 copy_from_extractor = &rdx_data;
732 copy_from_offset = 0;
733 integer_bytes = 8 + field_byte_width;
734 }
735 } else if (integer_bytes + field_byte_width <= 16) {
736 copy_from_extractor = &rdx_data;
737 copy_from_offset = integer_bytes - 8;
738 integer_bytes += field_byte_width;
739 } else {
740 // The last field didn't fit. I can't see how that would happen
741 // w/o the overall size being greater than 16 bytes. For now,
742 // return a nullptr return value object.
743 return return_valobj_sp;
744 }
745 } else if (field_compiler_type.IsFloatingPointType(count, is_complex)) {
746 // Structs with long doubles are always passed in memory.
747 if (*field_bit_width == 128) {
748 is_memory = true;
749 break;
750 } else if (*field_bit_width == 64) {
751 copy_from_offset = 0;
752 } else if (*field_bit_width == 32) {
753 // This one is kind of complicated. If we are in an "eightbyte"
754 // with another float, we'll be stuffed into an xmm register with
755 // it. If we are in an "eightbyte" with one or more ints, then we
756 // will be stuffed into the appropriate GPR with them.
757 bool in_gpr;
758 if (field_byte_offset % 8 == 0) {
759 // We are at the beginning of one of the eightbytes, so check the
760 // next element (if any)
761 if (idx == num_children - 1)
762 in_gpr = false;
763 else {
764 uint64_t next_field_bit_offset = 0;
765 CompilerType next_field_compiler_type =
766 return_compiler_type.GetFieldAtIndex(idx + 1, name,
767 &next_field_bit_offset,
768 nullptr, nullptr);
769 if (next_field_compiler_type.IsIntegerOrEnumerationType(
770 is_signed))
771 in_gpr = true;
772 else {
773 copy_from_offset = 0;
774 in_gpr = false;
775 }
776 }
777 } else if (field_byte_offset % 4 == 0) {
778 // We are inside of an eightbyte, so see if the field before us
779 // is floating point: This could happen if somebody put padding
780 // in the structure.
781 if (idx == 0)
782 in_gpr = false;
783 else {
784 uint64_t prev_field_bit_offset = 0;
785 CompilerType prev_field_compiler_type =
786 return_compiler_type.GetFieldAtIndex(idx - 1, name,
787 &prev_field_bit_offset,
788 nullptr, nullptr);
789 if (prev_field_compiler_type.IsIntegerOrEnumerationType(
790 is_signed))
791 in_gpr = true;
792 else {
793 copy_from_offset = 4;
794 in_gpr = false;
795 }
796 }
797 } else {
798 is_memory = true;
799 continue;
800 }
801
802 // Okay, we've figured out whether we are in GPR or XMM, now figure
803 // out which one.
804 if (in_gpr) {
805 if (integer_bytes < 8) {
806 // This is in RAX, copy from register to our result structure:
807 copy_from_extractor = &r3_data;
808 copy_from_offset = integer_bytes;
809 integer_bytes += field_byte_width;
810 } else {
811 copy_from_extractor = &rdx_data;
812 copy_from_offset = integer_bytes - 8;
813 integer_bytes += field_byte_width;
814 }
815 }
816 }
817 }
818
819 // These two tests are just sanity checks. If I somehow get the type
820 // calculation wrong above it is better to just return nothing than to
821 // assert or crash.
822 if (!copy_from_extractor)
823 return return_valobj_sp;
824 if (copy_from_offset + field_byte_width >
825 copy_from_extractor->GetByteSize())
826 return return_valobj_sp;
827
828 copy_from_extractor->CopyByteOrderedData(
829 copy_from_offset, field_byte_width,
830 data_sp->GetBytes() + field_byte_offset, field_byte_width,
831 target_byte_order);
832 }
833
834 if (!is_memory) {
835 // The result is in our data buffer. Let's make a variable object out
836 // of it:
837 return_valobj_sp = ValueObjectConstResult::Create(
838 &thread, return_compiler_type, ConstString(""), return_ext);
839 }
840 }
841
842 // FIXME: This is just taking a guess, r3 may very well no longer hold the
843 // return storage location.
844 // If we are going to do this right, when we make a new frame we should
845 // check to see if it uses a memory return, and if we are at the first
846 // instruction and if so stash away the return location. Then we would
847 // only return the memory return value if we know it is valid.
848
849 if (is_memory) {
850 unsigned r3_id =
851 reg_ctx_sp->GetRegisterInfoByName("r3", 0)->kinds[eRegisterKindLLDB];
852 lldb::addr_t storage_addr =
853 (uint64_t)thread.GetRegisterContext()->ReadRegisterAsUnsigned(r3_id,
854 0);
855 return_valobj_sp = ValueObjectMemory::Create(
856 &thread, "", Address(storage_addr, nullptr), return_compiler_type);
857 }
858 }
859
860 return return_valobj_sp;
861 }
862
CreateFunctionEntryUnwindPlan(UnwindPlan & unwind_plan)863 bool ABISysV_ppc::CreateFunctionEntryUnwindPlan(UnwindPlan &unwind_plan) {
864 unwind_plan.Clear();
865 unwind_plan.SetRegisterKind(eRegisterKindDWARF);
866
867 uint32_t lr_reg_num = dwarf_lr;
868 uint32_t sp_reg_num = dwarf_r1;
869 uint32_t pc_reg_num = dwarf_pc;
870
871 UnwindPlan::RowSP row(new UnwindPlan::Row);
872
873 // Our Call Frame Address is the stack pointer value
874 row->GetCFAValue().SetIsRegisterPlusOffset(sp_reg_num, 0);
875
876 // The previous PC is in the LR
877 row->SetRegisterLocationToRegister(pc_reg_num, lr_reg_num, true);
878 unwind_plan.AppendRow(row);
879
880 // All other registers are the same.
881
882 unwind_plan.SetSourceName("ppc at-func-entry default");
883 unwind_plan.SetSourcedFromCompiler(eLazyBoolNo);
884
885 return true;
886 }
887
CreateDefaultUnwindPlan(UnwindPlan & unwind_plan)888 bool ABISysV_ppc::CreateDefaultUnwindPlan(UnwindPlan &unwind_plan) {
889 unwind_plan.Clear();
890 unwind_plan.SetRegisterKind(eRegisterKindDWARF);
891
892 uint32_t sp_reg_num = dwarf_r1;
893 uint32_t pc_reg_num = dwarf_lr;
894
895 UnwindPlan::RowSP row(new UnwindPlan::Row);
896
897 const int32_t ptr_size = 4;
898 row->SetUnspecifiedRegistersAreUndefined(true);
899 row->GetCFAValue().SetIsRegisterDereferenced(sp_reg_num);
900
901 row->SetRegisterLocationToAtCFAPlusOffset(pc_reg_num, ptr_size * 1, true);
902 row->SetRegisterLocationToIsCFAPlusOffset(sp_reg_num, 0, true);
903
904 unwind_plan.AppendRow(row);
905 unwind_plan.SetSourceName("ppc default unwind plan");
906 unwind_plan.SetSourcedFromCompiler(eLazyBoolNo);
907 unwind_plan.SetUnwindPlanValidAtAllInstructions(eLazyBoolNo);
908 unwind_plan.SetUnwindPlanForSignalTrap(eLazyBoolNo);
909 unwind_plan.SetReturnAddressRegister(dwarf_lr);
910 return true;
911 }
912
RegisterIsVolatile(const RegisterInfo * reg_info)913 bool ABISysV_ppc::RegisterIsVolatile(const RegisterInfo *reg_info) {
914 return !RegisterIsCalleeSaved(reg_info);
915 }
916
917 // See "Register Usage" in the
918 // "System V Application Binary Interface"
919 // "64-bit PowerPC ELF Application Binary Interface Supplement" current version
920 // is 1.9 released 2004 at http://refspecs.linuxfoundation.org/ELF/ppc/PPC-
921 // elf64abi-1.9.pdf
922
RegisterIsCalleeSaved(const RegisterInfo * reg_info)923 bool ABISysV_ppc::RegisterIsCalleeSaved(const RegisterInfo *reg_info) {
924 if (reg_info) {
925 // Preserved registers are :
926 // r1,r2,r13-r31
927 // f14-f31 (not yet)
928 // v20-v31 (not yet)
929 // vrsave (not yet)
930
931 const char *name = reg_info->name;
932 if (name[0] == 'r') {
933 if ((name[1] == '1' || name[1] == '2') && name[2] == '\0')
934 return true;
935 if (name[1] == '1' && name[2] > '2')
936 return true;
937 if ((name[1] == '2' || name[1] == '3') && name[2] != '\0')
938 return true;
939 }
940
941 if (name[0] == 'f' && name[1] >= '0' && name[1] <= '9') {
942 if (name[3] == '1' && name[4] >= '4')
943 return true;
944 if ((name[3] == '2' || name[3] == '3') && name[4] != '\0')
945 return true;
946 }
947
948 if (name[0] == 's' && name[1] == 'p' && name[2] == '\0') // sp
949 return true;
950 if (name[0] == 'f' && name[1] == 'p' && name[2] == '\0') // fp
951 return true;
952 if (name[0] == 'p' && name[1] == 'c' && name[2] == '\0') // pc
953 return true;
954 }
955 return false;
956 }
957
Initialize()958 void ABISysV_ppc::Initialize() {
959 PluginManager::RegisterPlugin(GetPluginNameStatic(),
960 "System V ABI for ppc targets", CreateInstance);
961 }
962
Terminate()963 void ABISysV_ppc::Terminate() {
964 PluginManager::UnregisterPlugin(CreateInstance);
965 }
966