1 //===-- NativeRegisterContextLinux_arm64.cpp --------------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #if defined(__arm64__) || defined(__aarch64__)
11 
12 #include "NativeRegisterContextLinux_arm.h"
13 #include "NativeRegisterContextLinux_arm64.h"
14 
15 // C Includes
16 // C++ Includes
17 
18 // Other libraries and framework includes
19 #include "lldb/Core/RegisterValue.h"
20 #include "lldb/Host/common/NativeProcessProtocol.h"
21 #include "lldb/Utility/DataBufferHeap.h"
22 #include "lldb/Utility/Log.h"
23 #include "lldb/Utility/Status.h"
24 
25 #include "Plugins/Process/Linux/NativeProcessLinux.h"
26 #include "Plugins/Process/Linux/Procfs.h"
27 #include "Plugins/Process/POSIX/ProcessPOSIXLog.h"
28 #include "Plugins/Process/Utility/RegisterInfoPOSIX_arm64.h"
29 
30 // System includes - They have to be included after framework includes because
31 // they define some
32 // macros which collide with variable names in other modules
33 #include <sys/socket.h>
34 // NT_PRSTATUS and NT_FPREGSET definition
35 #include <elf.h>
36 // user_hwdebug_state definition
37 #include <asm/ptrace.h>
38 
39 #define REG_CONTEXT_SIZE (GetGPRSize() + GetFPRSize())
40 
41 using namespace lldb;
42 using namespace lldb_private;
43 using namespace lldb_private::process_linux;
44 
45 // ARM64 general purpose registers.
46 static const uint32_t g_gpr_regnums_arm64[] = {
47     gpr_x0_arm64,       gpr_x1_arm64,   gpr_x2_arm64,  gpr_x3_arm64,
48     gpr_x4_arm64,       gpr_x5_arm64,   gpr_x6_arm64,  gpr_x7_arm64,
49     gpr_x8_arm64,       gpr_x9_arm64,   gpr_x10_arm64, gpr_x11_arm64,
50     gpr_x12_arm64,      gpr_x13_arm64,  gpr_x14_arm64, gpr_x15_arm64,
51     gpr_x16_arm64,      gpr_x17_arm64,  gpr_x18_arm64, gpr_x19_arm64,
52     gpr_x20_arm64,      gpr_x21_arm64,  gpr_x22_arm64, gpr_x23_arm64,
53     gpr_x24_arm64,      gpr_x25_arm64,  gpr_x26_arm64, gpr_x27_arm64,
54     gpr_x28_arm64,      gpr_fp_arm64,   gpr_lr_arm64,  gpr_sp_arm64,
55     gpr_pc_arm64,       gpr_cpsr_arm64, gpr_w0_arm64,  gpr_w1_arm64,
56     gpr_w2_arm64,       gpr_w3_arm64,   gpr_w4_arm64,  gpr_w5_arm64,
57     gpr_w6_arm64,       gpr_w7_arm64,   gpr_w8_arm64,  gpr_w9_arm64,
58     gpr_w10_arm64,      gpr_w11_arm64,  gpr_w12_arm64, gpr_w13_arm64,
59     gpr_w14_arm64,      gpr_w15_arm64,  gpr_w16_arm64, gpr_w17_arm64,
60     gpr_w18_arm64,      gpr_w19_arm64,  gpr_w20_arm64, gpr_w21_arm64,
61     gpr_w22_arm64,      gpr_w23_arm64,  gpr_w24_arm64, gpr_w25_arm64,
62     gpr_w26_arm64,      gpr_w27_arm64,  gpr_w28_arm64,
63     LLDB_INVALID_REGNUM // register sets need to end with this flag
64 };
65 static_assert(((sizeof g_gpr_regnums_arm64 / sizeof g_gpr_regnums_arm64[0]) -
66                1) == k_num_gpr_registers_arm64,
67               "g_gpr_regnums_arm64 has wrong number of register infos");
68 
69 // ARM64 floating point registers.
70 static const uint32_t g_fpu_regnums_arm64[] = {
71     fpu_v0_arm64,       fpu_v1_arm64,   fpu_v2_arm64,  fpu_v3_arm64,
72     fpu_v4_arm64,       fpu_v5_arm64,   fpu_v6_arm64,  fpu_v7_arm64,
73     fpu_v8_arm64,       fpu_v9_arm64,   fpu_v10_arm64, fpu_v11_arm64,
74     fpu_v12_arm64,      fpu_v13_arm64,  fpu_v14_arm64, fpu_v15_arm64,
75     fpu_v16_arm64,      fpu_v17_arm64,  fpu_v18_arm64, fpu_v19_arm64,
76     fpu_v20_arm64,      fpu_v21_arm64,  fpu_v22_arm64, fpu_v23_arm64,
77     fpu_v24_arm64,      fpu_v25_arm64,  fpu_v26_arm64, fpu_v27_arm64,
78     fpu_v28_arm64,      fpu_v29_arm64,  fpu_v30_arm64, fpu_v31_arm64,
79     fpu_s0_arm64,       fpu_s1_arm64,   fpu_s2_arm64,  fpu_s3_arm64,
80     fpu_s4_arm64,       fpu_s5_arm64,   fpu_s6_arm64,  fpu_s7_arm64,
81     fpu_s8_arm64,       fpu_s9_arm64,   fpu_s10_arm64, fpu_s11_arm64,
82     fpu_s12_arm64,      fpu_s13_arm64,  fpu_s14_arm64, fpu_s15_arm64,
83     fpu_s16_arm64,      fpu_s17_arm64,  fpu_s18_arm64, fpu_s19_arm64,
84     fpu_s20_arm64,      fpu_s21_arm64,  fpu_s22_arm64, fpu_s23_arm64,
85     fpu_s24_arm64,      fpu_s25_arm64,  fpu_s26_arm64, fpu_s27_arm64,
86     fpu_s28_arm64,      fpu_s29_arm64,  fpu_s30_arm64, fpu_s31_arm64,
87 
88     fpu_d0_arm64,       fpu_d1_arm64,   fpu_d2_arm64,  fpu_d3_arm64,
89     fpu_d4_arm64,       fpu_d5_arm64,   fpu_d6_arm64,  fpu_d7_arm64,
90     fpu_d8_arm64,       fpu_d9_arm64,   fpu_d10_arm64, fpu_d11_arm64,
91     fpu_d12_arm64,      fpu_d13_arm64,  fpu_d14_arm64, fpu_d15_arm64,
92     fpu_d16_arm64,      fpu_d17_arm64,  fpu_d18_arm64, fpu_d19_arm64,
93     fpu_d20_arm64,      fpu_d21_arm64,  fpu_d22_arm64, fpu_d23_arm64,
94     fpu_d24_arm64,      fpu_d25_arm64,  fpu_d26_arm64, fpu_d27_arm64,
95     fpu_d28_arm64,      fpu_d29_arm64,  fpu_d30_arm64, fpu_d31_arm64,
96     fpu_fpsr_arm64,     fpu_fpcr_arm64,
97     LLDB_INVALID_REGNUM // register sets need to end with this flag
98 };
99 static_assert(((sizeof g_fpu_regnums_arm64 / sizeof g_fpu_regnums_arm64[0]) -
100                1) == k_num_fpr_registers_arm64,
101               "g_fpu_regnums_arm64 has wrong number of register infos");
102 
103 namespace {
104 // Number of register sets provided by this context.
105 enum { k_num_register_sets = 2 };
106 }
107 
108 // Register sets for ARM64.
109 static const RegisterSet g_reg_sets_arm64[k_num_register_sets] = {
110     {"General Purpose Registers", "gpr", k_num_gpr_registers_arm64,
111      g_gpr_regnums_arm64},
112     {"Floating Point Registers", "fpu", k_num_fpr_registers_arm64,
113      g_fpu_regnums_arm64}};
114 
115 std::unique_ptr<NativeRegisterContextLinux>
116 NativeRegisterContextLinux::CreateHostNativeRegisterContextLinux(
117     const ArchSpec &target_arch, NativeThreadProtocol &native_thread) {
118   switch (target_arch.GetMachine()) {
119   case llvm::Triple::arm:
120     return llvm::make_unique<NativeRegisterContextLinux_arm>(target_arch,
121                                                              native_thread);
122   case llvm::Triple::aarch64:
123     return llvm::make_unique<NativeRegisterContextLinux_arm64>(target_arch,
124                                                                native_thread);
125   default:
126     llvm_unreachable("have no register context for architecture");
127   }
128 }
129 
130 NativeRegisterContextLinux_arm64::NativeRegisterContextLinux_arm64(
131     const ArchSpec &target_arch, NativeThreadProtocol &native_thread)
132     : NativeRegisterContextLinux(native_thread,
133                                  new RegisterInfoPOSIX_arm64(target_arch)) {
134   switch (target_arch.GetMachine()) {
135   case llvm::Triple::aarch64:
136     m_reg_info.num_registers = k_num_registers_arm64;
137     m_reg_info.num_gpr_registers = k_num_gpr_registers_arm64;
138     m_reg_info.num_fpr_registers = k_num_fpr_registers_arm64;
139     m_reg_info.last_gpr = k_last_gpr_arm64;
140     m_reg_info.first_fpr = k_first_fpr_arm64;
141     m_reg_info.last_fpr = k_last_fpr_arm64;
142     m_reg_info.first_fpr_v = fpu_v0_arm64;
143     m_reg_info.last_fpr_v = fpu_v31_arm64;
144     m_reg_info.gpr_flags = gpr_cpsr_arm64;
145     break;
146   default:
147     llvm_unreachable("Unhandled target architecture.");
148     break;
149   }
150 
151   ::memset(&m_fpr, 0, sizeof(m_fpr));
152   ::memset(&m_gpr_arm64, 0, sizeof(m_gpr_arm64));
153   ::memset(&m_hwp_regs, 0, sizeof(m_hwp_regs));
154   ::memset(&m_hbr_regs, 0, sizeof(m_hbr_regs));
155 
156   // 16 is just a maximum value, query hardware for actual watchpoint count
157   m_max_hwp_supported = 16;
158   m_max_hbp_supported = 16;
159   m_refresh_hwdebug_info = true;
160 }
161 
162 uint32_t NativeRegisterContextLinux_arm64::GetRegisterSetCount() const {
163   return k_num_register_sets;
164 }
165 
166 const RegisterSet *
167 NativeRegisterContextLinux_arm64::GetRegisterSet(uint32_t set_index) const {
168   if (set_index < k_num_register_sets)
169     return &g_reg_sets_arm64[set_index];
170 
171   return nullptr;
172 }
173 
174 uint32_t NativeRegisterContextLinux_arm64::GetUserRegisterCount() const {
175   uint32_t count = 0;
176   for (uint32_t set_index = 0; set_index < k_num_register_sets; ++set_index)
177     count += g_reg_sets_arm64[set_index].num_registers;
178   return count;
179 }
180 
181 Status
182 NativeRegisterContextLinux_arm64::ReadRegister(const RegisterInfo *reg_info,
183                                                RegisterValue &reg_value) {
184   Status error;
185 
186   if (!reg_info) {
187     error.SetErrorString("reg_info NULL");
188     return error;
189   }
190 
191   const uint32_t reg = reg_info->kinds[lldb::eRegisterKindLLDB];
192 
193   if (IsFPR(reg)) {
194     error = ReadFPR();
195     if (error.Fail())
196       return error;
197   } else {
198     uint32_t full_reg = reg;
199     bool is_subreg = reg_info->invalidate_regs &&
200                      (reg_info->invalidate_regs[0] != LLDB_INVALID_REGNUM);
201 
202     if (is_subreg) {
203       // Read the full aligned 64-bit register.
204       full_reg = reg_info->invalidate_regs[0];
205     }
206 
207     error = ReadRegisterRaw(full_reg, reg_value);
208 
209     if (error.Success()) {
210       // If our read was not aligned (for ah,bh,ch,dh), shift our returned value
211       // one byte to the right.
212       if (is_subreg && (reg_info->byte_offset & 0x1))
213         reg_value.SetUInt64(reg_value.GetAsUInt64() >> 8);
214 
215       // If our return byte size was greater than the return value reg size,
216       // then
217       // use the type specified by reg_info rather than the uint64_t default
218       if (reg_value.GetByteSize() > reg_info->byte_size)
219         reg_value.SetType(reg_info);
220     }
221     return error;
222   }
223 
224   // Get pointer to m_fpr variable and set the data from it.
225   uint32_t fpr_offset = CalculateFprOffset(reg_info);
226   assert(fpr_offset < sizeof m_fpr);
227   uint8_t *src = (uint8_t *)&m_fpr + fpr_offset;
228   reg_value.SetFromMemoryData(reg_info, src, reg_info->byte_size,
229                               eByteOrderLittle, error);
230 
231   return error;
232 }
233 
234 Status NativeRegisterContextLinux_arm64::WriteRegister(
235     const RegisterInfo *reg_info, const RegisterValue &reg_value) {
236   if (!reg_info)
237     return Status("reg_info NULL");
238 
239   const uint32_t reg_index = reg_info->kinds[lldb::eRegisterKindLLDB];
240   if (reg_index == LLDB_INVALID_REGNUM)
241     return Status("no lldb regnum for %s", reg_info && reg_info->name
242                                                ? reg_info->name
243                                                : "<unknown register>");
244 
245   if (IsGPR(reg_index))
246     return WriteRegisterRaw(reg_index, reg_value);
247 
248   if (IsFPR(reg_index)) {
249     // Get pointer to m_fpr variable and set the data to it.
250     uint32_t fpr_offset = CalculateFprOffset(reg_info);
251     assert(fpr_offset < sizeof m_fpr);
252     uint8_t *dst = (uint8_t *)&m_fpr + fpr_offset;
253     switch (reg_info->byte_size) {
254     case 2:
255       *(uint16_t *)dst = reg_value.GetAsUInt16();
256       break;
257     case 4:
258       *(uint32_t *)dst = reg_value.GetAsUInt32();
259       break;
260     case 8:
261       *(uint64_t *)dst = reg_value.GetAsUInt64();
262       break;
263     default:
264       assert(false && "Unhandled data size.");
265       return Status("unhandled register data size %" PRIu32,
266                     reg_info->byte_size);
267     }
268 
269     Status error = WriteFPR();
270     if (error.Fail())
271       return error;
272 
273     return Status();
274   }
275 
276   return Status("failed - register wasn't recognized to be a GPR or an FPR, "
277                 "write strategy unknown");
278 }
279 
280 Status NativeRegisterContextLinux_arm64::ReadAllRegisterValues(
281     lldb::DataBufferSP &data_sp) {
282   Status error;
283 
284   data_sp.reset(new DataBufferHeap(REG_CONTEXT_SIZE, 0));
285   if (!data_sp)
286     return Status("failed to allocate DataBufferHeap instance of size %" PRIu64,
287                   REG_CONTEXT_SIZE);
288 
289   error = ReadGPR();
290   if (error.Fail())
291     return error;
292 
293   error = ReadFPR();
294   if (error.Fail())
295     return error;
296 
297   uint8_t *dst = data_sp->GetBytes();
298   if (dst == nullptr) {
299     error.SetErrorStringWithFormat("DataBufferHeap instance of size %" PRIu64
300                                    " returned a null pointer",
301                                    REG_CONTEXT_SIZE);
302     return error;
303   }
304 
305   ::memcpy(dst, &m_gpr_arm64, GetGPRSize());
306   dst += GetGPRSize();
307   ::memcpy(dst, &m_fpr, sizeof(m_fpr));
308 
309   return error;
310 }
311 
312 Status NativeRegisterContextLinux_arm64::WriteAllRegisterValues(
313     const lldb::DataBufferSP &data_sp) {
314   Status error;
315 
316   if (!data_sp) {
317     error.SetErrorStringWithFormat(
318         "NativeRegisterContextLinux_x86_64::%s invalid data_sp provided",
319         __FUNCTION__);
320     return error;
321   }
322 
323   if (data_sp->GetByteSize() != REG_CONTEXT_SIZE) {
324     error.SetErrorStringWithFormat(
325         "NativeRegisterContextLinux_x86_64::%s data_sp contained mismatched "
326         "data size, expected %" PRIu64 ", actual %" PRIu64,
327         __FUNCTION__, REG_CONTEXT_SIZE, data_sp->GetByteSize());
328     return error;
329   }
330 
331   uint8_t *src = data_sp->GetBytes();
332   if (src == nullptr) {
333     error.SetErrorStringWithFormat("NativeRegisterContextLinux_x86_64::%s "
334                                    "DataBuffer::GetBytes() returned a null "
335                                    "pointer",
336                                    __FUNCTION__);
337     return error;
338   }
339   ::memcpy(&m_gpr_arm64, src, GetRegisterInfoInterface().GetGPRSize());
340 
341   error = WriteGPR();
342   if (error.Fail())
343     return error;
344 
345   src += GetRegisterInfoInterface().GetGPRSize();
346   ::memcpy(&m_fpr, src, sizeof(m_fpr));
347 
348   error = WriteFPR();
349   if (error.Fail())
350     return error;
351 
352   return error;
353 }
354 
355 bool NativeRegisterContextLinux_arm64::IsGPR(unsigned reg) const {
356   return reg <= m_reg_info.last_gpr; // GPR's come first.
357 }
358 
359 bool NativeRegisterContextLinux_arm64::IsFPR(unsigned reg) const {
360   return (m_reg_info.first_fpr <= reg && reg <= m_reg_info.last_fpr);
361 }
362 
363 uint32_t NativeRegisterContextLinux_arm64::NumSupportedHardwareBreakpoints() {
364   Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_BREAKPOINTS));
365 
366   if (log)
367     log->Printf("NativeRegisterContextLinux_arm64::%s()", __FUNCTION__);
368 
369   Status error;
370 
371   // Read hardware breakpoint and watchpoint information.
372   error = ReadHardwareDebugInfo();
373 
374   if (error.Fail())
375     return 0;
376 
377   return m_max_hbp_supported;
378 }
379 
380 uint32_t
381 NativeRegisterContextLinux_arm64::SetHardwareBreakpoint(lldb::addr_t addr,
382                                                         size_t size) {
383   Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_BREAKPOINTS));
384   LLDB_LOG(log, "addr: {0:x}, size: {1:x}", addr, size);
385 
386   // Read hardware breakpoint and watchpoint information.
387   Status error = ReadHardwareDebugInfo();
388 
389   if (error.Fail())
390     return LLDB_INVALID_INDEX32;
391 
392   uint32_t control_value = 0, bp_index = 0;
393 
394   // Check if size has a valid hardware breakpoint length.
395   if (size != 4)
396     return LLDB_INVALID_INDEX32; // Invalid size for a AArch64 hardware
397                                  // breakpoint
398 
399   // Check 4-byte alignment for hardware breakpoint target address.
400   if (addr & 0x03)
401     return LLDB_INVALID_INDEX32; // Invalid address, should be 4-byte aligned.
402 
403   // Setup control value
404   control_value = 0;
405   control_value |= ((1 << size) - 1) << 5;
406   control_value |= (2 << 1) | 1;
407 
408   // Iterate over stored breakpoints and find a free bp_index
409   bp_index = LLDB_INVALID_INDEX32;
410   for (uint32_t i = 0; i < m_max_hbp_supported; i++) {
411     if ((m_hbr_regs[i].control & 1) == 0) {
412       bp_index = i; // Mark last free slot
413     } else if (m_hbr_regs[i].address == addr) {
414       return LLDB_INVALID_INDEX32; // We do not support duplicate breakpoints.
415     }
416   }
417 
418   if (bp_index == LLDB_INVALID_INDEX32)
419     return LLDB_INVALID_INDEX32;
420 
421   // Update breakpoint in local cache
422   m_hbr_regs[bp_index].real_addr = addr;
423   m_hbr_regs[bp_index].address = addr;
424   m_hbr_regs[bp_index].control = control_value;
425 
426   // PTRACE call to set corresponding hardware breakpoint register.
427   error = WriteHardwareDebugRegs(eDREGTypeBREAK);
428 
429   if (error.Fail()) {
430     m_hbr_regs[bp_index].address = 0;
431     m_hbr_regs[bp_index].control &= ~1;
432 
433     return LLDB_INVALID_INDEX32;
434   }
435 
436   return bp_index;
437 }
438 
439 bool NativeRegisterContextLinux_arm64::ClearHardwareBreakpoint(
440     uint32_t hw_idx) {
441   Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_BREAKPOINTS));
442   LLDB_LOG(log, "hw_idx: {0}", hw_idx);
443 
444   // Read hardware breakpoint and watchpoint information.
445   Status error = ReadHardwareDebugInfo();
446 
447   if (error.Fail())
448     return false;
449 
450   if (hw_idx >= m_max_hbp_supported)
451     return false;
452 
453   // Create a backup we can revert to in case of failure.
454   lldb::addr_t tempAddr = m_hbr_regs[hw_idx].address;
455   uint32_t tempControl = m_hbr_regs[hw_idx].control;
456 
457   m_hbr_regs[hw_idx].control &= ~1;
458   m_hbr_regs[hw_idx].address = 0;
459 
460   // PTRACE call to clear corresponding hardware breakpoint register.
461   error = WriteHardwareDebugRegs(eDREGTypeBREAK);
462 
463   if (error.Fail()) {
464     m_hbr_regs[hw_idx].control = tempControl;
465     m_hbr_regs[hw_idx].address = tempAddr;
466 
467     return false;
468   }
469 
470   return true;
471 }
472 
473 Status NativeRegisterContextLinux_arm64::GetHardwareBreakHitIndex(
474     uint32_t &bp_index, lldb::addr_t trap_addr) {
475   Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_BREAKPOINTS));
476 
477   if (log)
478     log->Printf("NativeRegisterContextLinux_arm64::%s()", __FUNCTION__);
479 
480   lldb::addr_t break_addr;
481 
482   for (bp_index = 0; bp_index < m_max_hbp_supported; ++bp_index) {
483     break_addr = m_hbr_regs[bp_index].address;
484 
485     if ((m_hbr_regs[bp_index].control & 0x1) && (trap_addr == break_addr)) {
486       m_hbr_regs[bp_index].hit_addr = trap_addr;
487       return Status();
488     }
489   }
490 
491   bp_index = LLDB_INVALID_INDEX32;
492   return Status();
493 }
494 
495 Status NativeRegisterContextLinux_arm64::ClearAllHardwareBreakpoints() {
496   Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_BREAKPOINTS));
497 
498   if (log)
499     log->Printf("NativeRegisterContextLinux_arm64::%s()", __FUNCTION__);
500 
501   Status error;
502 
503   // Read hardware breakpoint and watchpoint information.
504   error = ReadHardwareDebugInfo();
505 
506   if (error.Fail())
507     return error;
508 
509   lldb::addr_t tempAddr = 0;
510   uint32_t tempControl = 0;
511 
512   for (uint32_t i = 0; i < m_max_hbp_supported; i++) {
513     if (m_hbr_regs[i].control & 0x01) {
514       // Create a backup we can revert to in case of failure.
515       tempAddr = m_hbr_regs[i].address;
516       tempControl = m_hbr_regs[i].control;
517 
518       // Clear watchpoints in local cache
519       m_hbr_regs[i].control &= ~1;
520       m_hbr_regs[i].address = 0;
521 
522       // Ptrace call to update hardware debug registers
523       error = WriteHardwareDebugRegs(eDREGTypeBREAK);
524 
525       if (error.Fail()) {
526         m_hbr_regs[i].control = tempControl;
527         m_hbr_regs[i].address = tempAddr;
528 
529         return error;
530       }
531     }
532   }
533 
534   return Status();
535 }
536 
537 uint32_t NativeRegisterContextLinux_arm64::NumSupportedHardwareWatchpoints() {
538   Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_WATCHPOINTS));
539 
540   // Read hardware breakpoint and watchpoint information.
541   Status error = ReadHardwareDebugInfo();
542 
543   if (error.Fail())
544     return 0;
545 
546   LLDB_LOG(log, "{0}", m_max_hwp_supported);
547   return m_max_hwp_supported;
548 }
549 
550 uint32_t NativeRegisterContextLinux_arm64::SetHardwareWatchpoint(
551     lldb::addr_t addr, size_t size, uint32_t watch_flags) {
552   Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_WATCHPOINTS));
553   LLDB_LOG(log, "addr: {0:x}, size: {1:x} watch_flags: {2:x}", addr, size,
554            watch_flags);
555 
556   // Read hardware breakpoint and watchpoint information.
557   Status error = ReadHardwareDebugInfo();
558 
559   if (error.Fail())
560     return LLDB_INVALID_INDEX32;
561 
562   uint32_t control_value = 0, wp_index = 0;
563   lldb::addr_t real_addr = addr;
564 
565   // Check if we are setting watchpoint other than read/write/access
566   // Also update watchpoint flag to match AArch64 write-read bit configuration.
567   switch (watch_flags) {
568   case 1:
569     watch_flags = 2;
570     break;
571   case 2:
572     watch_flags = 1;
573     break;
574   case 3:
575     break;
576   default:
577     return LLDB_INVALID_INDEX32;
578   }
579 
580   // Check if size has a valid hardware watchpoint length.
581   if (size != 1 && size != 2 && size != 4 && size != 8)
582     return LLDB_INVALID_INDEX32;
583 
584   // Check 8-byte alignment for hardware watchpoint target address.
585   // Below is a hack to recalculate address and size in order to
586   // make sure we can watch non 8-byte alligned addresses as well.
587   if (addr & 0x07) {
588     uint8_t watch_mask = (addr & 0x07) + size;
589 
590     if (watch_mask > 0x08)
591       return LLDB_INVALID_INDEX32;
592     else if (watch_mask <= 0x02)
593       size = 2;
594     else if (watch_mask <= 0x04)
595       size = 4;
596     else
597       size = 8;
598 
599     addr = addr & (~0x07);
600   }
601 
602   // Setup control value
603   control_value = watch_flags << 3;
604   control_value |= ((1 << size) - 1) << 5;
605   control_value |= (2 << 1) | 1;
606 
607   // Iterate over stored watchpoints and find a free wp_index
608   wp_index = LLDB_INVALID_INDEX32;
609   for (uint32_t i = 0; i < m_max_hwp_supported; i++) {
610     if ((m_hwp_regs[i].control & 1) == 0) {
611       wp_index = i; // Mark last free slot
612     } else if (m_hwp_regs[i].address == addr) {
613       return LLDB_INVALID_INDEX32; // We do not support duplicate watchpoints.
614     }
615   }
616 
617   if (wp_index == LLDB_INVALID_INDEX32)
618     return LLDB_INVALID_INDEX32;
619 
620   // Update watchpoint in local cache
621   m_hwp_regs[wp_index].real_addr = real_addr;
622   m_hwp_regs[wp_index].address = addr;
623   m_hwp_regs[wp_index].control = control_value;
624 
625   // PTRACE call to set corresponding watchpoint register.
626   error = WriteHardwareDebugRegs(eDREGTypeWATCH);
627 
628   if (error.Fail()) {
629     m_hwp_regs[wp_index].address = 0;
630     m_hwp_regs[wp_index].control &= ~1;
631 
632     return LLDB_INVALID_INDEX32;
633   }
634 
635   return wp_index;
636 }
637 
638 bool NativeRegisterContextLinux_arm64::ClearHardwareWatchpoint(
639     uint32_t wp_index) {
640   Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_WATCHPOINTS));
641   LLDB_LOG(log, "wp_index: {0}", wp_index);
642 
643   // Read hardware breakpoint and watchpoint information.
644   Status error = ReadHardwareDebugInfo();
645 
646   if (error.Fail())
647     return false;
648 
649   if (wp_index >= m_max_hwp_supported)
650     return false;
651 
652   // Create a backup we can revert to in case of failure.
653   lldb::addr_t tempAddr = m_hwp_regs[wp_index].address;
654   uint32_t tempControl = m_hwp_regs[wp_index].control;
655 
656   // Update watchpoint in local cache
657   m_hwp_regs[wp_index].control &= ~1;
658   m_hwp_regs[wp_index].address = 0;
659 
660   // Ptrace call to update hardware debug registers
661   error = WriteHardwareDebugRegs(eDREGTypeWATCH);
662 
663   if (error.Fail()) {
664     m_hwp_regs[wp_index].control = tempControl;
665     m_hwp_regs[wp_index].address = tempAddr;
666 
667     return false;
668   }
669 
670   return true;
671 }
672 
673 Status NativeRegisterContextLinux_arm64::ClearAllHardwareWatchpoints() {
674   // Read hardware breakpoint and watchpoint information.
675   Status error = ReadHardwareDebugInfo();
676 
677   if (error.Fail())
678     return error;
679 
680   lldb::addr_t tempAddr = 0;
681   uint32_t tempControl = 0;
682 
683   for (uint32_t i = 0; i < m_max_hwp_supported; i++) {
684     if (m_hwp_regs[i].control & 0x01) {
685       // Create a backup we can revert to in case of failure.
686       tempAddr = m_hwp_regs[i].address;
687       tempControl = m_hwp_regs[i].control;
688 
689       // Clear watchpoints in local cache
690       m_hwp_regs[i].control &= ~1;
691       m_hwp_regs[i].address = 0;
692 
693       // Ptrace call to update hardware debug registers
694       error = WriteHardwareDebugRegs(eDREGTypeWATCH);
695 
696       if (error.Fail()) {
697         m_hwp_regs[i].control = tempControl;
698         m_hwp_regs[i].address = tempAddr;
699 
700         return error;
701       }
702     }
703   }
704 
705   return Status();
706 }
707 
708 uint32_t
709 NativeRegisterContextLinux_arm64::GetWatchpointSize(uint32_t wp_index) {
710   Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_WATCHPOINTS));
711   LLDB_LOG(log, "wp_index: {0}", wp_index);
712 
713   switch ((m_hwp_regs[wp_index].control >> 5) & 0xff) {
714   case 0x01:
715     return 1;
716   case 0x03:
717     return 2;
718   case 0x0f:
719     return 4;
720   case 0xff:
721     return 8;
722   default:
723     return 0;
724   }
725 }
726 bool NativeRegisterContextLinux_arm64::WatchpointIsEnabled(uint32_t wp_index) {
727   Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_WATCHPOINTS));
728   LLDB_LOG(log, "wp_index: {0}", wp_index);
729 
730   if ((m_hwp_regs[wp_index].control & 0x1) == 0x1)
731     return true;
732   else
733     return false;
734 }
735 
736 Status NativeRegisterContextLinux_arm64::GetWatchpointHitIndex(
737     uint32_t &wp_index, lldb::addr_t trap_addr) {
738   Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_WATCHPOINTS));
739   LLDB_LOG(log, "wp_index: {0}, trap_addr: {1:x}", wp_index, trap_addr);
740 
741   uint32_t watch_size;
742   lldb::addr_t watch_addr;
743 
744   for (wp_index = 0; wp_index < m_max_hwp_supported; ++wp_index) {
745     watch_size = GetWatchpointSize(wp_index);
746     watch_addr = m_hwp_regs[wp_index].address;
747 
748     if (WatchpointIsEnabled(wp_index) && trap_addr >= watch_addr &&
749         trap_addr < watch_addr + watch_size) {
750       m_hwp_regs[wp_index].hit_addr = trap_addr;
751       return Status();
752     }
753   }
754 
755   wp_index = LLDB_INVALID_INDEX32;
756   return Status();
757 }
758 
759 lldb::addr_t
760 NativeRegisterContextLinux_arm64::GetWatchpointAddress(uint32_t wp_index) {
761   Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_WATCHPOINTS));
762   LLDB_LOG(log, "wp_index: {0}", wp_index);
763 
764   if (wp_index >= m_max_hwp_supported)
765     return LLDB_INVALID_ADDRESS;
766 
767   if (WatchpointIsEnabled(wp_index))
768     return m_hwp_regs[wp_index].real_addr;
769   else
770     return LLDB_INVALID_ADDRESS;
771 }
772 
773 lldb::addr_t
774 NativeRegisterContextLinux_arm64::GetWatchpointHitAddress(uint32_t wp_index) {
775   Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_WATCHPOINTS));
776   LLDB_LOG(log, "wp_index: {0}", wp_index);
777 
778   if (wp_index >= m_max_hwp_supported)
779     return LLDB_INVALID_ADDRESS;
780 
781   if (WatchpointIsEnabled(wp_index))
782     return m_hwp_regs[wp_index].hit_addr;
783   else
784     return LLDB_INVALID_ADDRESS;
785 }
786 
787 Status NativeRegisterContextLinux_arm64::ReadHardwareDebugInfo() {
788   if (!m_refresh_hwdebug_info) {
789     return Status();
790   }
791 
792   ::pid_t tid = m_thread.GetID();
793 
794   int regset = NT_ARM_HW_WATCH;
795   struct iovec ioVec;
796   struct user_hwdebug_state dreg_state;
797   Status error;
798 
799   ioVec.iov_base = &dreg_state;
800   ioVec.iov_len = sizeof(dreg_state);
801   error = NativeProcessLinux::PtraceWrapper(PTRACE_GETREGSET, tid, &regset,
802                                             &ioVec, ioVec.iov_len);
803 
804   if (error.Fail())
805     return error;
806 
807   m_max_hwp_supported = dreg_state.dbg_info & 0xff;
808 
809   regset = NT_ARM_HW_BREAK;
810   error = NativeProcessLinux::PtraceWrapper(PTRACE_GETREGSET, tid, &regset,
811                                             &ioVec, ioVec.iov_len);
812 
813   if (error.Fail())
814     return error;
815 
816   m_max_hbp_supported = dreg_state.dbg_info & 0xff;
817   m_refresh_hwdebug_info = false;
818 
819   return error;
820 }
821 
822 Status NativeRegisterContextLinux_arm64::WriteHardwareDebugRegs(int hwbType) {
823   struct iovec ioVec;
824   struct user_hwdebug_state dreg_state;
825   Status error;
826 
827   memset(&dreg_state, 0, sizeof(dreg_state));
828   ioVec.iov_base = &dreg_state;
829 
830   if (hwbType == eDREGTypeWATCH) {
831     hwbType = NT_ARM_HW_WATCH;
832     ioVec.iov_len = sizeof(dreg_state.dbg_info) + sizeof(dreg_state.pad) +
833                     (sizeof(dreg_state.dbg_regs[0]) * m_max_hwp_supported);
834 
835     for (uint32_t i = 0; i < m_max_hwp_supported; i++) {
836       dreg_state.dbg_regs[i].addr = m_hwp_regs[i].address;
837       dreg_state.dbg_regs[i].ctrl = m_hwp_regs[i].control;
838     }
839   } else {
840     hwbType = NT_ARM_HW_BREAK;
841     ioVec.iov_len = sizeof(dreg_state.dbg_info) + sizeof(dreg_state.pad) +
842                     (sizeof(dreg_state.dbg_regs[0]) * m_max_hbp_supported);
843 
844     for (uint32_t i = 0; i < m_max_hbp_supported; i++) {
845       dreg_state.dbg_regs[i].addr = m_hbr_regs[i].address;
846       dreg_state.dbg_regs[i].ctrl = m_hbr_regs[i].control;
847     }
848   }
849 
850   return NativeProcessLinux::PtraceWrapper(PTRACE_SETREGSET, m_thread.GetID(),
851                                            &hwbType, &ioVec, ioVec.iov_len);
852 }
853 
854 Status NativeRegisterContextLinux_arm64::DoReadRegisterValue(
855     uint32_t offset, const char *reg_name, uint32_t size,
856     RegisterValue &value) {
857   Status error;
858   if (offset > sizeof(struct user_pt_regs)) {
859     offset -= sizeof(struct user_pt_regs);
860     if (offset > sizeof(struct user_fpsimd_state)) {
861       error.SetErrorString("invalid offset value");
862       return error;
863     }
864     elf_fpregset_t regs;
865     int regset = NT_FPREGSET;
866     struct iovec ioVec;
867 
868     ioVec.iov_base = &regs;
869     ioVec.iov_len = sizeof regs;
870     error = NativeProcessLinux::PtraceWrapper(
871         PTRACE_GETREGSET, m_thread.GetID(), &regset, &ioVec, sizeof regs);
872     if (error.Success()) {
873       value.SetBytes((void *)(((unsigned char *)(&regs)) + offset), 16,
874                      m_thread.GetProcess().GetByteOrder());
875     }
876   } else {
877     elf_gregset_t regs;
878     int regset = NT_PRSTATUS;
879     struct iovec ioVec;
880 
881     ioVec.iov_base = &regs;
882     ioVec.iov_len = sizeof regs;
883     error = NativeProcessLinux::PtraceWrapper(
884         PTRACE_GETREGSET, m_thread.GetID(), &regset, &ioVec, sizeof regs);
885     if (error.Success()) {
886       value.SetBytes((void *)(((unsigned char *)(regs)) + offset), 8,
887                      m_thread.GetProcess().GetByteOrder());
888     }
889   }
890   return error;
891 }
892 
893 Status NativeRegisterContextLinux_arm64::DoWriteRegisterValue(
894     uint32_t offset, const char *reg_name, const RegisterValue &value) {
895   Status error;
896   ::pid_t tid = m_thread.GetID();
897   if (offset > sizeof(struct user_pt_regs)) {
898     offset -= sizeof(struct user_pt_regs);
899     if (offset > sizeof(struct user_fpsimd_state)) {
900       error.SetErrorString("invalid offset value");
901       return error;
902     }
903     elf_fpregset_t regs;
904     int regset = NT_FPREGSET;
905     struct iovec ioVec;
906 
907     ioVec.iov_base = &regs;
908     ioVec.iov_len = sizeof regs;
909     error = NativeProcessLinux::PtraceWrapper(PTRACE_GETREGSET, tid, &regset,
910                                               &ioVec, sizeof regs);
911 
912     if (error.Success()) {
913       ::memcpy((void *)(((unsigned char *)(&regs)) + offset), value.GetBytes(),
914                16);
915       error = NativeProcessLinux::PtraceWrapper(PTRACE_SETREGSET, tid, &regset,
916                                                 &ioVec, sizeof regs);
917     }
918   } else {
919     elf_gregset_t regs;
920     int regset = NT_PRSTATUS;
921     struct iovec ioVec;
922 
923     ioVec.iov_base = &regs;
924     ioVec.iov_len = sizeof regs;
925     error = NativeProcessLinux::PtraceWrapper(PTRACE_GETREGSET, tid, &regset,
926                                               &ioVec, sizeof regs);
927     if (error.Success()) {
928       ::memcpy((void *)(((unsigned char *)(&regs)) + offset), value.GetBytes(),
929                8);
930       error = NativeProcessLinux::PtraceWrapper(PTRACE_SETREGSET, tid, &regset,
931                                                 &ioVec, sizeof regs);
932     }
933   }
934   return error;
935 }
936 
937 Status NativeRegisterContextLinux_arm64::DoReadGPR(void *buf, size_t buf_size) {
938   int regset = NT_PRSTATUS;
939   struct iovec ioVec;
940   Status error;
941 
942   ioVec.iov_base = buf;
943   ioVec.iov_len = buf_size;
944   return NativeProcessLinux::PtraceWrapper(PTRACE_GETREGSET, m_thread.GetID(),
945                                            &regset, &ioVec, buf_size);
946 }
947 
948 Status NativeRegisterContextLinux_arm64::DoWriteGPR(void *buf,
949                                                     size_t buf_size) {
950   int regset = NT_PRSTATUS;
951   struct iovec ioVec;
952   Status error;
953 
954   ioVec.iov_base = buf;
955   ioVec.iov_len = buf_size;
956   return NativeProcessLinux::PtraceWrapper(PTRACE_SETREGSET, m_thread.GetID(),
957                                            &regset, &ioVec, buf_size);
958 }
959 
960 Status NativeRegisterContextLinux_arm64::DoReadFPR(void *buf, size_t buf_size) {
961   int regset = NT_FPREGSET;
962   struct iovec ioVec;
963   Status error;
964 
965   ioVec.iov_base = buf;
966   ioVec.iov_len = buf_size;
967   return NativeProcessLinux::PtraceWrapper(PTRACE_GETREGSET, m_thread.GetID(),
968                                            &regset, &ioVec, buf_size);
969 }
970 
971 Status NativeRegisterContextLinux_arm64::DoWriteFPR(void *buf,
972                                                     size_t buf_size) {
973   int regset = NT_FPREGSET;
974   struct iovec ioVec;
975   Status error;
976 
977   ioVec.iov_base = buf;
978   ioVec.iov_len = buf_size;
979   return NativeProcessLinux::PtraceWrapper(PTRACE_SETREGSET, m_thread.GetID(),
980                                            &regset, &ioVec, buf_size);
981 }
982 
983 uint32_t NativeRegisterContextLinux_arm64::CalculateFprOffset(
984     const RegisterInfo *reg_info) const {
985   return reg_info->byte_offset -
986          GetRegisterInfoAtIndex(m_reg_info.first_fpr)->byte_offset;
987 }
988 
989 #endif // defined (__arm64__) || defined (__aarch64__)
990