1 //===-- DNBArchImplARM64.cpp ------------------------------------*- C++ -*-===//
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 //  Created by Greg Clayton on 6/25/07.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #if defined(__arm__) || defined(__arm64__) || defined(__aarch64__)
14 
15 #include "MacOSX/arm64/DNBArchImplARM64.h"
16 
17 #if defined(ARM_THREAD_STATE64_COUNT)
18 
19 #include "DNB.h"
20 #include "DNBBreakpoint.h"
21 #include "DNBLog.h"
22 #include "DNBRegisterInfo.h"
23 #include "MacOSX/MachProcess.h"
24 #include "MacOSX/MachThread.h"
25 
26 #include <inttypes.h>
27 #include <sys/sysctl.h>
28 
29 #if __has_feature(ptrauth_calls)
30 #include <ptrauth.h>
31 #endif
32 
33 // Break only in privileged or user mode
34 // (PAC bits in the DBGWVRn_EL1 watchpoint control register)
35 #define S_USER ((uint32_t)(2u << 1))
36 
37 #define BCR_ENABLE ((uint32_t)(1u))
38 #define WCR_ENABLE ((uint32_t)(1u))
39 
40 // Watchpoint load/store
41 // (LSC bits in the DBGWVRn_EL1 watchpoint control register)
42 #define WCR_LOAD ((uint32_t)(1u << 3))
43 #define WCR_STORE ((uint32_t)(1u << 4))
44 
45 // Enable breakpoint, watchpoint, and vector catch debug exceptions.
46 // (MDE bit in the MDSCR_EL1 register.  Equivalent to the MDBGen bit in
47 // DBGDSCRext in Aarch32)
48 #define MDE_ENABLE ((uint32_t)(1u << 15))
49 
50 // Single instruction step
51 // (SS bit in the MDSCR_EL1 register)
52 #define SS_ENABLE ((uint32_t)(1u))
53 
54 static const uint8_t g_arm64_breakpoint_opcode[] = {
55     0x00, 0x00, 0x20, 0xD4}; // "brk #0", 0xd4200000 in BE byte order
56 
57 // If we need to set one logical watchpoint by using
58 // two hardware watchpoint registers, the watchpoint
59 // will be split into a "high" and "low" watchpoint.
60 // Record both of them in the LoHi array.
61 
62 // It's safe to initialize to all 0's since
63 // hi > lo and therefore LoHi[i] cannot be 0.
64 static uint32_t LoHi[16] = {0};
65 
66 void DNBArchMachARM64::Initialize() {
67   DNBArchPluginInfo arch_plugin_info = {
68       CPU_TYPE_ARM64, DNBArchMachARM64::Create,
69       DNBArchMachARM64::GetRegisterSetInfo,
70       DNBArchMachARM64::SoftwareBreakpointOpcode};
71 
72   // Register this arch plug-in with the main protocol class
73   DNBArchProtocol::RegisterArchPlugin(arch_plugin_info);
74 
75   DNBArchPluginInfo arch_plugin_info_32 = {
76       CPU_TYPE_ARM64_32, DNBArchMachARM64::Create,
77       DNBArchMachARM64::GetRegisterSetInfo,
78       DNBArchMachARM64::SoftwareBreakpointOpcode};
79 
80   // Register this arch plug-in with the main protocol class
81   DNBArchProtocol::RegisterArchPlugin(arch_plugin_info_32);
82 }
83 
84 DNBArchProtocol *DNBArchMachARM64::Create(MachThread *thread) {
85   DNBArchMachARM64 *obj = new DNBArchMachARM64(thread);
86 
87   return obj;
88 }
89 
90 const uint8_t *
91 DNBArchMachARM64::SoftwareBreakpointOpcode(nub_size_t byte_size) {
92   return g_arm64_breakpoint_opcode;
93 }
94 
95 uint32_t DNBArchMachARM64::GetCPUType() { return CPU_TYPE_ARM64; }
96 
97 uint64_t DNBArchMachARM64::GetPC(uint64_t failValue) {
98   // Get program counter
99   if (GetGPRState(false) == KERN_SUCCESS)
100 #if defined(__LP64__)
101     return arm_thread_state64_get_pc(m_state.context.gpr);
102 #else
103     return m_state.context.gpr.__pc;
104 #endif
105   return failValue;
106 }
107 
108 kern_return_t DNBArchMachARM64::SetPC(uint64_t value) {
109   // Get program counter
110   kern_return_t err = GetGPRState(false);
111   if (err == KERN_SUCCESS) {
112 #if defined(__LP64__)
113 #if __has_feature(ptrauth_calls)
114     // The incoming value could be garbage.  Strip it to avoid
115     // trapping when it gets resigned in the thread state.
116     value = (uint64_t) ptrauth_strip((void*) value, ptrauth_key_function_pointer);
117     value = (uint64_t) ptrauth_sign_unauthenticated((void*) value, ptrauth_key_function_pointer, 0);
118 #endif
119     arm_thread_state64_set_pc_fptr (m_state.context.gpr, (void*) value);
120 #else
121     m_state.context.gpr.__pc = value;
122 #endif
123     err = SetGPRState();
124   }
125   return err == KERN_SUCCESS;
126 }
127 
128 uint64_t DNBArchMachARM64::GetSP(uint64_t failValue) {
129   // Get stack pointer
130   if (GetGPRState(false) == KERN_SUCCESS)
131 #if defined(__LP64__)
132     return arm_thread_state64_get_sp(m_state.context.gpr);
133 #else
134     return m_state.context.gpr.__sp;
135 #endif
136   return failValue;
137 }
138 
139 kern_return_t DNBArchMachARM64::GetGPRState(bool force) {
140   int set = e_regSetGPR;
141   // Check if we have valid cached registers
142   if (!force && m_state.GetError(set, Read) == KERN_SUCCESS)
143     return KERN_SUCCESS;
144 
145   // Read the registers from our thread
146   mach_msg_type_number_t count = e_regSetGPRCount;
147   kern_return_t kret =
148       ::thread_get_state(m_thread->MachPortNumber(), ARM_THREAD_STATE64,
149                          (thread_state_t)&m_state.context.gpr, &count);
150   if (DNBLogEnabledForAny(LOG_THREAD)) {
151     uint64_t *x = &m_state.context.gpr.__x[0];
152     DNBLogThreaded(
153         "thread_get_state(0x%4.4x, %u, &gpr, %u) => 0x%8.8x (count = %u) regs"
154         "\n   x0=%16.16llx"
155         "\n   x1=%16.16llx"
156         "\n   x2=%16.16llx"
157         "\n   x3=%16.16llx"
158         "\n   x4=%16.16llx"
159         "\n   x5=%16.16llx"
160         "\n   x6=%16.16llx"
161         "\n   x7=%16.16llx"
162         "\n   x8=%16.16llx"
163         "\n   x9=%16.16llx"
164         "\n  x10=%16.16llx"
165         "\n  x11=%16.16llx"
166         "\n  x12=%16.16llx"
167         "\n  x13=%16.16llx"
168         "\n  x14=%16.16llx"
169         "\n  x15=%16.16llx"
170         "\n  x16=%16.16llx"
171         "\n  x17=%16.16llx"
172         "\n  x18=%16.16llx"
173         "\n  x19=%16.16llx"
174         "\n  x20=%16.16llx"
175         "\n  x21=%16.16llx"
176         "\n  x22=%16.16llx"
177         "\n  x23=%16.16llx"
178         "\n  x24=%16.16llx"
179         "\n  x25=%16.16llx"
180         "\n  x26=%16.16llx"
181         "\n  x27=%16.16llx"
182         "\n  x28=%16.16llx"
183         "\n   fp=%16.16llx"
184         "\n   lr=%16.16llx"
185         "\n   sp=%16.16llx"
186         "\n   pc=%16.16llx"
187         "\n cpsr=%8.8x",
188         m_thread->MachPortNumber(), e_regSetGPR, e_regSetGPRCount, kret, count,
189         x[0], x[1], x[2], x[3], x[4], x[5], x[6], x[7], x[8], x[9], x[0], x[11],
190         x[12], x[13], x[14], x[15], x[16], x[17], x[18], x[19], x[20], x[21],
191         x[22], x[23], x[24], x[25], x[26], x[27], x[28],
192 #if defined(__LP64__)
193         (uint64_t) arm_thread_state64_get_fp (m_state.context.gpr),
194         (uint64_t) arm_thread_state64_get_lr (m_state.context.gpr),
195         (uint64_t) arm_thread_state64_get_sp (m_state.context.gpr),
196         (uint64_t) arm_thread_state64_get_pc (m_state.context.gpr),
197 #else
198         m_state.context.gpr.__fp, m_state.context.gpr.__lr,
199         m_state.context.gpr.__sp, m_state.context.gpr.__pc,
200 #endif
201         m_state.context.gpr.__cpsr);
202   }
203   m_state.SetError(set, Read, kret);
204   return kret;
205 }
206 
207 kern_return_t DNBArchMachARM64::GetVFPState(bool force) {
208   int set = e_regSetVFP;
209   // Check if we have valid cached registers
210   if (!force && m_state.GetError(set, Read) == KERN_SUCCESS)
211     return KERN_SUCCESS;
212 
213   // Read the registers from our thread
214   mach_msg_type_number_t count = e_regSetVFPCount;
215   kern_return_t kret =
216       ::thread_get_state(m_thread->MachPortNumber(), ARM_NEON_STATE64,
217                          (thread_state_t)&m_state.context.vfp, &count);
218   if (DNBLogEnabledForAny(LOG_THREAD)) {
219 #if defined(__arm64__) || defined(__aarch64__)
220     DNBLogThreaded(
221         "thread_get_state(0x%4.4x, %u, &vfp, %u) => 0x%8.8x (count = %u) regs"
222         "\n   q0  = 0x%16.16llx%16.16llx"
223         "\n   q1  = 0x%16.16llx%16.16llx"
224         "\n   q2  = 0x%16.16llx%16.16llx"
225         "\n   q3  = 0x%16.16llx%16.16llx"
226         "\n   q4  = 0x%16.16llx%16.16llx"
227         "\n   q5  = 0x%16.16llx%16.16llx"
228         "\n   q6  = 0x%16.16llx%16.16llx"
229         "\n   q7  = 0x%16.16llx%16.16llx"
230         "\n   q8  = 0x%16.16llx%16.16llx"
231         "\n   q9  = 0x%16.16llx%16.16llx"
232         "\n   q10 = 0x%16.16llx%16.16llx"
233         "\n   q11 = 0x%16.16llx%16.16llx"
234         "\n   q12 = 0x%16.16llx%16.16llx"
235         "\n   q13 = 0x%16.16llx%16.16llx"
236         "\n   q14 = 0x%16.16llx%16.16llx"
237         "\n   q15 = 0x%16.16llx%16.16llx"
238         "\n   q16 = 0x%16.16llx%16.16llx"
239         "\n   q17 = 0x%16.16llx%16.16llx"
240         "\n   q18 = 0x%16.16llx%16.16llx"
241         "\n   q19 = 0x%16.16llx%16.16llx"
242         "\n   q20 = 0x%16.16llx%16.16llx"
243         "\n   q21 = 0x%16.16llx%16.16llx"
244         "\n   q22 = 0x%16.16llx%16.16llx"
245         "\n   q23 = 0x%16.16llx%16.16llx"
246         "\n   q24 = 0x%16.16llx%16.16llx"
247         "\n   q25 = 0x%16.16llx%16.16llx"
248         "\n   q26 = 0x%16.16llx%16.16llx"
249         "\n   q27 = 0x%16.16llx%16.16llx"
250         "\n   q28 = 0x%16.16llx%16.16llx"
251         "\n   q29 = 0x%16.16llx%16.16llx"
252         "\n   q30 = 0x%16.16llx%16.16llx"
253         "\n   q31 = 0x%16.16llx%16.16llx"
254         "\n  fpsr = 0x%8.8x"
255         "\n  fpcr = 0x%8.8x\n\n",
256         m_thread->MachPortNumber(), e_regSetVFP, e_regSetVFPCount, kret, count,
257         ((uint64_t *)&m_state.context.vfp.__v[0])[0],
258         ((uint64_t *)&m_state.context.vfp.__v[0])[1],
259         ((uint64_t *)&m_state.context.vfp.__v[1])[0],
260         ((uint64_t *)&m_state.context.vfp.__v[1])[1],
261         ((uint64_t *)&m_state.context.vfp.__v[2])[0],
262         ((uint64_t *)&m_state.context.vfp.__v[2])[1],
263         ((uint64_t *)&m_state.context.vfp.__v[3])[0],
264         ((uint64_t *)&m_state.context.vfp.__v[3])[1],
265         ((uint64_t *)&m_state.context.vfp.__v[4])[0],
266         ((uint64_t *)&m_state.context.vfp.__v[4])[1],
267         ((uint64_t *)&m_state.context.vfp.__v[5])[0],
268         ((uint64_t *)&m_state.context.vfp.__v[5])[1],
269         ((uint64_t *)&m_state.context.vfp.__v[6])[0],
270         ((uint64_t *)&m_state.context.vfp.__v[6])[1],
271         ((uint64_t *)&m_state.context.vfp.__v[7])[0],
272         ((uint64_t *)&m_state.context.vfp.__v[7])[1],
273         ((uint64_t *)&m_state.context.vfp.__v[8])[0],
274         ((uint64_t *)&m_state.context.vfp.__v[8])[1],
275         ((uint64_t *)&m_state.context.vfp.__v[9])[0],
276         ((uint64_t *)&m_state.context.vfp.__v[9])[1],
277         ((uint64_t *)&m_state.context.vfp.__v[10])[0],
278         ((uint64_t *)&m_state.context.vfp.__v[10])[1],
279         ((uint64_t *)&m_state.context.vfp.__v[11])[0],
280         ((uint64_t *)&m_state.context.vfp.__v[11])[1],
281         ((uint64_t *)&m_state.context.vfp.__v[12])[0],
282         ((uint64_t *)&m_state.context.vfp.__v[12])[1],
283         ((uint64_t *)&m_state.context.vfp.__v[13])[0],
284         ((uint64_t *)&m_state.context.vfp.__v[13])[1],
285         ((uint64_t *)&m_state.context.vfp.__v[14])[0],
286         ((uint64_t *)&m_state.context.vfp.__v[14])[1],
287         ((uint64_t *)&m_state.context.vfp.__v[15])[0],
288         ((uint64_t *)&m_state.context.vfp.__v[15])[1],
289         ((uint64_t *)&m_state.context.vfp.__v[16])[0],
290         ((uint64_t *)&m_state.context.vfp.__v[16])[1],
291         ((uint64_t *)&m_state.context.vfp.__v[17])[0],
292         ((uint64_t *)&m_state.context.vfp.__v[17])[1],
293         ((uint64_t *)&m_state.context.vfp.__v[18])[0],
294         ((uint64_t *)&m_state.context.vfp.__v[18])[1],
295         ((uint64_t *)&m_state.context.vfp.__v[19])[0],
296         ((uint64_t *)&m_state.context.vfp.__v[19])[1],
297         ((uint64_t *)&m_state.context.vfp.__v[20])[0],
298         ((uint64_t *)&m_state.context.vfp.__v[20])[1],
299         ((uint64_t *)&m_state.context.vfp.__v[21])[0],
300         ((uint64_t *)&m_state.context.vfp.__v[21])[1],
301         ((uint64_t *)&m_state.context.vfp.__v[22])[0],
302         ((uint64_t *)&m_state.context.vfp.__v[22])[1],
303         ((uint64_t *)&m_state.context.vfp.__v[23])[0],
304         ((uint64_t *)&m_state.context.vfp.__v[23])[1],
305         ((uint64_t *)&m_state.context.vfp.__v[24])[0],
306         ((uint64_t *)&m_state.context.vfp.__v[24])[1],
307         ((uint64_t *)&m_state.context.vfp.__v[25])[0],
308         ((uint64_t *)&m_state.context.vfp.__v[25])[1],
309         ((uint64_t *)&m_state.context.vfp.__v[26])[0],
310         ((uint64_t *)&m_state.context.vfp.__v[26])[1],
311         ((uint64_t *)&m_state.context.vfp.__v[27])[0],
312         ((uint64_t *)&m_state.context.vfp.__v[27])[1],
313         ((uint64_t *)&m_state.context.vfp.__v[28])[0],
314         ((uint64_t *)&m_state.context.vfp.__v[28])[1],
315         ((uint64_t *)&m_state.context.vfp.__v[29])[0],
316         ((uint64_t *)&m_state.context.vfp.__v[29])[1],
317         ((uint64_t *)&m_state.context.vfp.__v[30])[0],
318         ((uint64_t *)&m_state.context.vfp.__v[30])[1],
319         ((uint64_t *)&m_state.context.vfp.__v[31])[0],
320         ((uint64_t *)&m_state.context.vfp.__v[31])[1],
321         m_state.context.vfp.__fpsr, m_state.context.vfp.__fpcr);
322 #endif
323   }
324   m_state.SetError(set, Read, kret);
325   return kret;
326 }
327 
328 kern_return_t DNBArchMachARM64::GetEXCState(bool force) {
329   int set = e_regSetEXC;
330   // Check if we have valid cached registers
331   if (!force && m_state.GetError(set, Read) == KERN_SUCCESS)
332     return KERN_SUCCESS;
333 
334   // Read the registers from our thread
335   mach_msg_type_number_t count = e_regSetEXCCount;
336   kern_return_t kret =
337       ::thread_get_state(m_thread->MachPortNumber(), ARM_EXCEPTION_STATE64,
338                          (thread_state_t)&m_state.context.exc, &count);
339   m_state.SetError(set, Read, kret);
340   return kret;
341 }
342 
343 static void DumpDBGState(const arm_debug_state_t &dbg) {
344   uint32_t i = 0;
345   for (i = 0; i < 16; i++)
346     DNBLogThreadedIf(LOG_STEP, "BVR%-2u/BCR%-2u = { 0x%8.8x, 0x%8.8x } "
347                                "WVR%-2u/WCR%-2u = { 0x%8.8x, 0x%8.8x }",
348                      i, i, dbg.__bvr[i], dbg.__bcr[i], i, i, dbg.__wvr[i],
349                      dbg.__wcr[i]);
350 }
351 
352 kern_return_t DNBArchMachARM64::GetDBGState(bool force) {
353   int set = e_regSetDBG;
354 
355   // Check if we have valid cached registers
356   if (!force && m_state.GetError(set, Read) == KERN_SUCCESS)
357     return KERN_SUCCESS;
358 
359   // Read the registers from our thread
360   mach_msg_type_number_t count = e_regSetDBGCount;
361   kern_return_t kret =
362       ::thread_get_state(m_thread->MachPortNumber(), ARM_DEBUG_STATE64,
363                          (thread_state_t)&m_state.dbg, &count);
364   m_state.SetError(set, Read, kret);
365 
366   return kret;
367 }
368 
369 kern_return_t DNBArchMachARM64::SetGPRState() {
370   int set = e_regSetGPR;
371   kern_return_t kret = ::thread_set_state(
372       m_thread->MachPortNumber(), ARM_THREAD_STATE64,
373       (thread_state_t)&m_state.context.gpr, e_regSetGPRCount);
374   m_state.SetError(set, Write,
375                    kret); // Set the current write error for this register set
376   m_state.InvalidateRegisterSetState(set); // Invalidate the current register
377                                            // state in case registers are read
378                                            // back differently
379   return kret;                             // Return the error code
380 }
381 
382 kern_return_t DNBArchMachARM64::SetVFPState() {
383   int set = e_regSetVFP;
384   kern_return_t kret = ::thread_set_state(
385       m_thread->MachPortNumber(), ARM_NEON_STATE64,
386       (thread_state_t)&m_state.context.vfp, e_regSetVFPCount);
387   m_state.SetError(set, Write,
388                    kret); // Set the current write error for this register set
389   m_state.InvalidateRegisterSetState(set); // Invalidate the current register
390                                            // state in case registers are read
391                                            // back differently
392   return kret;                             // Return the error code
393 }
394 
395 kern_return_t DNBArchMachARM64::SetEXCState() {
396   int set = e_regSetEXC;
397   kern_return_t kret = ::thread_set_state(
398       m_thread->MachPortNumber(), ARM_EXCEPTION_STATE64,
399       (thread_state_t)&m_state.context.exc, e_regSetEXCCount);
400   m_state.SetError(set, Write,
401                    kret); // Set the current write error for this register set
402   m_state.InvalidateRegisterSetState(set); // Invalidate the current register
403                                            // state in case registers are read
404                                            // back differently
405   return kret;                             // Return the error code
406 }
407 
408 kern_return_t DNBArchMachARM64::SetDBGState(bool also_set_on_task) {
409   int set = e_regSetDBG;
410   kern_return_t kret =
411       ::thread_set_state(m_thread->MachPortNumber(), ARM_DEBUG_STATE64,
412                          (thread_state_t)&m_state.dbg, e_regSetDBGCount);
413   if (also_set_on_task) {
414     kern_return_t task_kret = task_set_state(
415         m_thread->Process()->Task().TaskPort(), ARM_DEBUG_STATE64,
416         (thread_state_t)&m_state.dbg, e_regSetDBGCount);
417     if (task_kret != KERN_SUCCESS)
418       DNBLogThreadedIf(LOG_WATCHPOINTS, "DNBArchMachARM64::SetDBGState failed "
419                                         "to set debug control register state: "
420                                         "0x%8.8x.",
421                        task_kret);
422   }
423   m_state.SetError(set, Write,
424                    kret); // Set the current write error for this register set
425   m_state.InvalidateRegisterSetState(set); // Invalidate the current register
426                                            // state in case registers are read
427                                            // back differently
428 
429   return kret; // Return the error code
430 }
431 
432 void DNBArchMachARM64::ThreadWillResume() {
433   // Do we need to step this thread? If so, let the mach thread tell us so.
434   if (m_thread->IsStepping()) {
435     EnableHardwareSingleStep(true);
436   }
437 
438   // Disable the triggered watchpoint temporarily before we resume.
439   // Plus, we try to enable hardware single step to execute past the instruction
440   // which triggered our watchpoint.
441   if (m_watchpoint_did_occur) {
442     if (m_watchpoint_hw_index >= 0) {
443       kern_return_t kret = GetDBGState(false);
444       if (kret == KERN_SUCCESS &&
445           !IsWatchpointEnabled(m_state.dbg, m_watchpoint_hw_index)) {
446         // The watchpoint might have been disabled by the user.  We don't need
447         // to do anything at all
448         // to enable hardware single stepping.
449         m_watchpoint_did_occur = false;
450         m_watchpoint_hw_index = -1;
451         return;
452       }
453 
454       DisableHardwareWatchpoint(m_watchpoint_hw_index, false);
455       DNBLogThreadedIf(LOG_WATCHPOINTS, "DNBArchMachARM::ThreadWillResume() "
456                                         "DisableHardwareWatchpoint(%d) called",
457                        m_watchpoint_hw_index);
458 
459       // Enable hardware single step to move past the watchpoint-triggering
460       // instruction.
461       m_watchpoint_resume_single_step_enabled =
462           (EnableHardwareSingleStep(true) == KERN_SUCCESS);
463 
464       // If we are not able to enable single step to move past the
465       // watchpoint-triggering instruction,
466       // at least we should reset the two watchpoint member variables so that
467       // the next time around
468       // this callback function is invoked, the enclosing logical branch is
469       // skipped.
470       if (!m_watchpoint_resume_single_step_enabled) {
471         // Reset the two watchpoint member variables.
472         m_watchpoint_did_occur = false;
473         m_watchpoint_hw_index = -1;
474         DNBLogThreadedIf(
475             LOG_WATCHPOINTS,
476             "DNBArchMachARM::ThreadWillResume() failed to enable single step");
477       } else
478         DNBLogThreadedIf(LOG_WATCHPOINTS, "DNBArchMachARM::ThreadWillResume() "
479                                           "succeeded to enable single step");
480     }
481   }
482 }
483 
484 bool DNBArchMachARM64::NotifyException(MachException::Data &exc) {
485 
486   switch (exc.exc_type) {
487   default:
488     break;
489   case EXC_BREAKPOINT:
490     if (exc.exc_data.size() == 2 && exc.exc_data[0] == EXC_ARM_DA_DEBUG) {
491       // The data break address is passed as exc_data[1].
492       nub_addr_t addr = exc.exc_data[1];
493       // Find the hardware index with the side effect of possibly massaging the
494       // addr to return the starting address as seen from the debugger side.
495       uint32_t hw_index = GetHardwareWatchpointHit(addr);
496 
497       // One logical watchpoint was split into two watchpoint locations because
498       // it was too big.  If the watchpoint exception is indicating the 2nd half
499       // of the two-parter, find the address of the 1st half and report that --
500       // that's what lldb is going to expect to see.
501       DNBLogThreadedIf(LOG_WATCHPOINTS, "DNBArchMachARM::NotifyException "
502                                         "watchpoint %d was hit on address "
503                                         "0x%llx",
504                        hw_index, (uint64_t)addr);
505       const int num_watchpoints = NumSupportedHardwareWatchpoints();
506       for (int i = 0; i < num_watchpoints; i++) {
507         if (LoHi[i] != 0 && LoHi[i] == hw_index && LoHi[i] != i &&
508             GetWatchpointAddressByIndex(i) != INVALID_NUB_ADDRESS) {
509           addr = GetWatchpointAddressByIndex(i);
510           DNBLogThreadedIf(LOG_WATCHPOINTS, "DNBArchMachARM::NotifyException "
511                                             "It is a linked watchpoint; "
512                                             "rewritten to index %d addr 0x%llx",
513                            LoHi[i], (uint64_t)addr);
514         }
515       }
516 
517       if (hw_index != INVALID_NUB_HW_INDEX) {
518         m_watchpoint_did_occur = true;
519         m_watchpoint_hw_index = hw_index;
520         exc.exc_data[1] = addr;
521         // Piggyback the hw_index in the exc.data.
522         exc.exc_data.push_back(hw_index);
523       }
524 
525       return true;
526     }
527     break;
528   }
529   return false;
530 }
531 
532 bool DNBArchMachARM64::ThreadDidStop() {
533   bool success = true;
534 
535   m_state.InvalidateAllRegisterStates();
536 
537   if (m_watchpoint_resume_single_step_enabled) {
538     // Great!  We now disable the hardware single step as well as re-enable the
539     // hardware watchpoint.
540     // See also ThreadWillResume().
541     if (EnableHardwareSingleStep(false) == KERN_SUCCESS) {
542       if (m_watchpoint_did_occur && m_watchpoint_hw_index >= 0) {
543         ReenableHardwareWatchpoint(m_watchpoint_hw_index);
544         m_watchpoint_resume_single_step_enabled = false;
545         m_watchpoint_did_occur = false;
546         m_watchpoint_hw_index = -1;
547       } else {
548         DNBLogError("internal error detected: m_watchpoint_resume_step_enabled "
549                     "is true but (m_watchpoint_did_occur && "
550                     "m_watchpoint_hw_index >= 0) does not hold!");
551       }
552     } else {
553       DNBLogError("internal error detected: m_watchpoint_resume_step_enabled "
554                   "is true but unable to disable single step!");
555     }
556   }
557 
558   // Are we stepping a single instruction?
559   if (GetGPRState(true) == KERN_SUCCESS) {
560     // We are single stepping, was this the primary thread?
561     if (m_thread->IsStepping()) {
562       // This was the primary thread, we need to clear the trace
563       // bit if so.
564       success = EnableHardwareSingleStep(false) == KERN_SUCCESS;
565     } else {
566       // The MachThread will automatically restore the suspend count
567       // in ThreadDidStop(), so we don't need to do anything here if
568       // we weren't the primary thread the last time
569     }
570   }
571   return success;
572 }
573 
574 // Set the single step bit in the processor status register.
575 kern_return_t DNBArchMachARM64::EnableHardwareSingleStep(bool enable) {
576   DNBError err;
577   DNBLogThreadedIf(LOG_STEP, "%s( enable = %d )", __FUNCTION__, enable);
578 
579   err = GetGPRState(false);
580 
581   if (err.Fail()) {
582     err.LogThreaded("%s: failed to read the GPR registers", __FUNCTION__);
583     return err.Status();
584   }
585 
586   err = GetDBGState(false);
587 
588   if (err.Fail()) {
589     err.LogThreaded("%s: failed to read the DBG registers", __FUNCTION__);
590     return err.Status();
591   }
592 
593   if (enable) {
594     DNBLogThreadedIf(LOG_STEP,
595                      "%s: Setting MDSCR_EL1 Single Step bit at pc 0x%llx",
596 #if defined(__LP64__)
597                      __FUNCTION__, (uint64_t)arm_thread_state64_get_pc (m_state.context.gpr));
598 #else
599                      __FUNCTION__, (uint64_t)m_state.context.gpr.__pc);
600 #endif
601     m_state.dbg.__mdscr_el1 |= SS_ENABLE;
602   } else {
603     DNBLogThreadedIf(LOG_STEP,
604                      "%s: Clearing MDSCR_EL1 Single Step bit at pc 0x%llx",
605 #if defined(__LP64__)
606                      __FUNCTION__, (uint64_t)arm_thread_state64_get_pc (m_state.context.gpr));
607 #else
608                      __FUNCTION__, (uint64_t)m_state.context.gpr.__pc);
609 #endif
610     m_state.dbg.__mdscr_el1 &= ~(SS_ENABLE);
611   }
612 
613   return SetDBGState(false);
614 }
615 
616 // return 1 if bit "BIT" is set in "value"
617 static inline uint32_t bit(uint32_t value, uint32_t bit) {
618   return (value >> bit) & 1u;
619 }
620 
621 // return the bitfield "value[msbit:lsbit]".
622 static inline uint64_t bits(uint64_t value, uint32_t msbit, uint32_t lsbit) {
623   assert(msbit >= lsbit);
624   uint64_t shift_left = sizeof(value) * 8 - 1 - msbit;
625   value <<=
626       shift_left; // shift anything above the msbit off of the unsigned edge
627   value >>= shift_left + lsbit; // shift it back again down to the lsbit
628                                 // (including undoing any shift from above)
629   return value;                 // return our result
630 }
631 
632 uint32_t DNBArchMachARM64::NumSupportedHardwareWatchpoints() {
633   // Set the init value to something that will let us know that we need to
634   // autodetect how many watchpoints are supported dynamically...
635   static uint32_t g_num_supported_hw_watchpoints = UINT_MAX;
636   if (g_num_supported_hw_watchpoints == UINT_MAX) {
637     // Set this to zero in case we can't tell if there are any HW breakpoints
638     g_num_supported_hw_watchpoints = 0;
639 
640     size_t len;
641     uint32_t n = 0;
642     len = sizeof(n);
643     if (::sysctlbyname("hw.optional.watchpoint", &n, &len, NULL, 0) == 0) {
644       g_num_supported_hw_watchpoints = n;
645       DNBLogThreadedIf(LOG_THREAD, "hw.optional.watchpoint=%u", n);
646     } else {
647 // For AArch64 we would need to look at ID_AA64DFR0_EL1 but debugserver runs in
648 // EL0 so it can't
649 // access that reg.  The kernel should have filled in the sysctls based on it
650 // though.
651 #if defined(__arm__)
652       uint32_t register_DBGDIDR;
653 
654       asm("mrc p14, 0, %0, c0, c0, 0" : "=r"(register_DBGDIDR));
655       uint32_t numWRPs = bits(register_DBGDIDR, 31, 28);
656       // Zero is reserved for the WRP count, so don't increment it if it is zero
657       if (numWRPs > 0)
658         numWRPs++;
659       g_num_supported_hw_watchpoints = numWRPs;
660       DNBLogThreadedIf(LOG_THREAD,
661                        "Number of supported hw watchpoints via asm():  %d",
662                        g_num_supported_hw_watchpoints);
663 #endif
664     }
665   }
666   return g_num_supported_hw_watchpoints;
667 }
668 
669 uint32_t DNBArchMachARM64::NumSupportedHardwareBreakpoints() {
670   // Set the init value to something that will let us know that we need to
671   // autodetect how many breakpoints are supported dynamically...
672   static uint32_t g_num_supported_hw_breakpoints = UINT_MAX;
673   if (g_num_supported_hw_breakpoints == UINT_MAX) {
674     // Set this to zero in case we can't tell if there are any HW breakpoints
675     g_num_supported_hw_breakpoints = 0;
676 
677     size_t len;
678     uint32_t n = 0;
679     len = sizeof(n);
680     if (::sysctlbyname("hw.optional.breakpoint", &n, &len, NULL, 0) == 0) {
681       g_num_supported_hw_breakpoints = n;
682       DNBLogThreadedIf(LOG_THREAD, "hw.optional.breakpoint=%u", n);
683     } else {
684 // For AArch64 we would need to look at ID_AA64DFR0_EL1 but debugserver runs in
685 // EL0 so it can't access that reg.  The kernel should have filled in the
686 // sysctls based on it though.
687 #if defined(__arm__)
688       uint32_t register_DBGDIDR;
689 
690       asm("mrc p14, 0, %0, c0, c0, 0" : "=r"(register_DBGDIDR));
691       uint32_t numWRPs = bits(register_DBGDIDR, 31, 28);
692       // Zero is reserved for the WRP count, so don't increment it if it is zero
693       if (numWRPs > 0)
694         numWRPs++;
695       g_num_supported_hw_breakpoints = numWRPs;
696       DNBLogThreadedIf(LOG_THREAD,
697                        "Number of supported hw breakpoint via asm():  %d",
698                        g_num_supported_hw_breakpoints);
699 #endif
700     }
701   }
702   return g_num_supported_hw_breakpoints;
703 }
704 
705 uint32_t DNBArchMachARM64::EnableHardwareBreakpoint(nub_addr_t addr,
706                                                     nub_size_t size,
707                                                     bool also_set_on_task) {
708   DNBLogThreadedIf(LOG_WATCHPOINTS,
709                    "DNBArchMachARM64::EnableHardwareBreakpoint(addr = "
710                    "0x%8.8llx, size = %zu)",
711                    (uint64_t)addr, size);
712 
713   const uint32_t num_hw_breakpoints = NumSupportedHardwareBreakpoints();
714 
715   nub_addr_t aligned_bp_address = addr;
716   uint32_t control_value = 0;
717 
718   switch (size) {
719   case 2:
720     control_value = (0x3 << 5) | 7;
721     aligned_bp_address &= ~1;
722     break;
723   case 4:
724     control_value = (0xfu << 5) | 7;
725     aligned_bp_address &= ~3;
726     break;
727   };
728 
729   // Read the debug state
730   kern_return_t kret = GetDBGState(false);
731   if (kret == KERN_SUCCESS) {
732     // Check to make sure we have the needed hardware support
733     uint32_t i = 0;
734 
735     for (i = 0; i < num_hw_breakpoints; ++i) {
736       if ((m_state.dbg.__bcr[i] & BCR_ENABLE) == 0)
737         break; // We found an available hw breakpoint slot (in i)
738     }
739 
740     // See if we found an available hw breakpoint slot above
741     if (i < num_hw_breakpoints) {
742       m_state.dbg.__bvr[i] = aligned_bp_address;
743       m_state.dbg.__bcr[i] = control_value;
744 
745       DNBLogThreadedIf(LOG_WATCHPOINTS,
746                        "DNBArchMachARM64::EnableHardwareBreakpoint() "
747                        "adding breakpoint on address 0x%llx with control "
748                        "register value 0x%x",
749                        (uint64_t)m_state.dbg.__bvr[i],
750                        (uint32_t)m_state.dbg.__bcr[i]);
751 
752       // The kernel will set the MDE_ENABLE bit in the MDSCR_EL1 for us
753       // automatically, don't need to do it here.
754       kret = SetDBGState(also_set_on_task);
755 
756       DNBLogThreadedIf(LOG_WATCHPOINTS,
757                        "DNBArchMachARM64::"
758                        "EnableHardwareBreakpoint() "
759                        "SetDBGState() => 0x%8.8x.",
760                        kret);
761 
762       if (kret == KERN_SUCCESS)
763         return i;
764     } else {
765       DNBLogThreadedIf(LOG_WATCHPOINTS,
766                        "DNBArchMachARM64::"
767                        "EnableHardwareBreakpoint(): All "
768                        "hardware resources (%u) are in use.",
769                        num_hw_breakpoints);
770     }
771   }
772   return INVALID_NUB_HW_INDEX;
773 }
774 
775 uint32_t DNBArchMachARM64::EnableHardwareWatchpoint(nub_addr_t addr,
776                                                     nub_size_t size, bool read,
777                                                     bool write,
778                                                     bool also_set_on_task) {
779   DNBLogThreadedIf(LOG_WATCHPOINTS,
780                    "DNBArchMachARM64::EnableHardwareWatchpoint(addr = "
781                    "0x%8.8llx, size = %zu, read = %u, write = %u)",
782                    (uint64_t)addr, size, read, write);
783 
784   const uint32_t num_hw_watchpoints = NumSupportedHardwareWatchpoints();
785 
786   // Can't watch zero bytes
787   if (size == 0)
788     return INVALID_NUB_HW_INDEX;
789 
790   // We must watch for either read or write
791   if (read == false && write == false)
792     return INVALID_NUB_HW_INDEX;
793 
794   // Otherwise, can't watch more than 8 bytes per WVR/WCR pair
795   if (size > 8)
796     return INVALID_NUB_HW_INDEX;
797 
798   // Aarch64 watchpoints are in one of two forms: (1) 1-8 bytes, aligned to
799   // an 8 byte address, or (2) a power-of-two size region of memory; minimum
800   // 8 bytes, maximum 2GB; the starting address must be aligned to that power
801   // of two.
802   //
803   // For (1), 1-8 byte watchpoints, using the Byte Address Selector field in
804   // DBGWCR<n>.BAS.  Any of the bytes may be watched, but if multiple bytes
805   // are watched, the bytes selected must be contiguous.  The start address
806   // watched must be doubleword (8-byte) aligned; if the start address is
807   // word (4-byte) aligned, only 4 bytes can be watched.
808   //
809   // For (2), the MASK field in DBGWCR<n>.MASK is used.
810   //
811   // See the ARM ARM, section "Watchpoint exceptions", and more specifically,
812   // "Watchpoint data address comparisons".
813   //
814   // debugserver today only supports (1) - the Byte Address Selector 1-8 byte
815   // watchpoints that are 8-byte aligned.  To support larger watchpoints,
816   // debugserver would need to interpret the mach exception when the watched
817   // region was hit, see if the address accessed lies within the subset
818   // of the power-of-two region that lldb asked us to watch (v. ARM ARM,
819   // "Determining the memory location that caused a Watchpoint exception"),
820   // and silently resume the inferior (disable watchpoint, stepi, re-enable
821   // watchpoint) if the address lies outside the region that lldb asked us
822   // to watch.
823   //
824   // Alternatively, lldb would need to be prepared for a larger region
825   // being watched than it requested, and silently resume the inferior if
826   // the accessed address is outside the region lldb wants to watch.
827 
828   nub_addr_t aligned_wp_address = addr & ~0x7;
829   uint32_t addr_dword_offset = addr & 0x7;
830 
831   // Do we need to split up this logical watchpoint into two hardware watchpoint
832   // registers?
833   // e.g. a watchpoint of length 4 on address 6.  We need do this with
834   //   one watchpoint on address 0 with bytes 6 & 7 being monitored
835   //   one watchpoint on address 8 with bytes 0, 1, 2, 3 being monitored
836 
837   if (addr_dword_offset + size > 8) {
838     DNBLogThreadedIf(LOG_WATCHPOINTS, "DNBArchMachARM64::"
839                                       "EnableHardwareWatchpoint(addr = "
840                                       "0x%8.8llx, size = %zu) needs two "
841                                       "hardware watchpoints slots to monitor",
842                      (uint64_t)addr, size);
843     int low_watchpoint_size = 8 - addr_dword_offset;
844     int high_watchpoint_size = addr_dword_offset + size - 8;
845 
846     uint32_t lo = EnableHardwareWatchpoint(addr, low_watchpoint_size, read,
847                                            write, also_set_on_task);
848     if (lo == INVALID_NUB_HW_INDEX)
849       return INVALID_NUB_HW_INDEX;
850     uint32_t hi =
851         EnableHardwareWatchpoint(aligned_wp_address + 8, high_watchpoint_size,
852                                  read, write, also_set_on_task);
853     if (hi == INVALID_NUB_HW_INDEX) {
854       DisableHardwareWatchpoint(lo, also_set_on_task);
855       return INVALID_NUB_HW_INDEX;
856     }
857     // Tag this lo->hi mapping in our database.
858     LoHi[lo] = hi;
859     return lo;
860   }
861 
862   // At this point
863   //  1 aligned_wp_address is the requested address rounded down to 8-byte
864   //  alignment
865   //  2 addr_dword_offset is the offset into that double word (8-byte) region
866   //  that we are watching
867   //  3 size is the number of bytes within that 8-byte region that we are
868   //  watching
869 
870   // Set the Byte Address Selects bits DBGWCRn_EL1 bits [12:5] based on the
871   // above.
872   // The bit shift and negation operation will give us 0b11 for 2, 0b1111 for 4,
873   // etc, up to 0b11111111 for 8.
874   // then we shift those bits left by the offset into this dword that we are
875   // interested in.
876   // e.g. if we are watching bytes 4,5,6,7 in a dword we want a BAS of
877   // 0b11110000.
878   uint32_t byte_address_select = ((1 << size) - 1) << addr_dword_offset;
879 
880   // Read the debug state
881   kern_return_t kret = GetDBGState(false);
882 
883   if (kret == KERN_SUCCESS) {
884     // Check to make sure we have the needed hardware support
885     uint32_t i = 0;
886 
887     for (i = 0; i < num_hw_watchpoints; ++i) {
888       if ((m_state.dbg.__wcr[i] & WCR_ENABLE) == 0)
889         break; // We found an available hw watchpoint slot (in i)
890     }
891 
892     // See if we found an available hw watchpoint slot above
893     if (i < num_hw_watchpoints) {
894       // DumpDBGState(m_state.dbg);
895 
896       // Clear any previous LoHi joined-watchpoint that may have been in use
897       LoHi[i] = 0;
898 
899       // shift our Byte Address Select bits up to the correct bit range for the
900       // DBGWCRn_EL1
901       byte_address_select = byte_address_select << 5;
902 
903       // Make sure bits 1:0 are clear in our address
904       m_state.dbg.__wvr[i] = aligned_wp_address;   // DVA (Data Virtual Address)
905       m_state.dbg.__wcr[i] = byte_address_select | // Which bytes that follow
906                                                    // the DVA that we will watch
907                              S_USER |              // Stop only in user mode
908                              (read ? WCR_LOAD : 0) |   // Stop on read access?
909                              (write ? WCR_STORE : 0) | // Stop on write access?
910                              WCR_ENABLE; // Enable this watchpoint;
911 
912       DNBLogThreadedIf(
913           LOG_WATCHPOINTS, "DNBArchMachARM64::EnableHardwareWatchpoint() "
914                            "adding watchpoint on address 0x%llx with control "
915                            "register value 0x%x",
916           (uint64_t)m_state.dbg.__wvr[i], (uint32_t)m_state.dbg.__wcr[i]);
917 
918       // The kernel will set the MDE_ENABLE bit in the MDSCR_EL1 for us
919       // automatically, don't need to do it here.
920 
921       kret = SetDBGState(also_set_on_task);
922       // DumpDBGState(m_state.dbg);
923 
924       DNBLogThreadedIf(LOG_WATCHPOINTS, "DNBArchMachARM64::"
925                                         "EnableHardwareWatchpoint() "
926                                         "SetDBGState() => 0x%8.8x.",
927                        kret);
928 
929       if (kret == KERN_SUCCESS)
930         return i;
931     } else {
932       DNBLogThreadedIf(LOG_WATCHPOINTS, "DNBArchMachARM64::"
933                                         "EnableHardwareWatchpoint(): All "
934                                         "hardware resources (%u) are in use.",
935                        num_hw_watchpoints);
936     }
937   }
938   return INVALID_NUB_HW_INDEX;
939 }
940 
941 bool DNBArchMachARM64::ReenableHardwareWatchpoint(uint32_t hw_index) {
942   // If this logical watchpoint # is actually implemented using
943   // two hardware watchpoint registers, re-enable both of them.
944 
945   if (hw_index < NumSupportedHardwareWatchpoints() && LoHi[hw_index]) {
946     return ReenableHardwareWatchpoint_helper(hw_index) &&
947            ReenableHardwareWatchpoint_helper(LoHi[hw_index]);
948   } else {
949     return ReenableHardwareWatchpoint_helper(hw_index);
950   }
951 }
952 
953 bool DNBArchMachARM64::ReenableHardwareWatchpoint_helper(uint32_t hw_index) {
954   kern_return_t kret = GetDBGState(false);
955   if (kret != KERN_SUCCESS)
956     return false;
957 
958   const uint32_t num_hw_points = NumSupportedHardwareWatchpoints();
959   if (hw_index >= num_hw_points)
960     return false;
961 
962   m_state.dbg.__wvr[hw_index] = m_disabled_watchpoints[hw_index].addr;
963   m_state.dbg.__wcr[hw_index] = m_disabled_watchpoints[hw_index].control;
964 
965   DNBLogThreadedIf(LOG_WATCHPOINTS, "DNBArchMachARM64::"
966                                     "EnableHardwareWatchpoint( %u ) - WVR%u = "
967                                     "0x%8.8llx  WCR%u = 0x%8.8llx",
968                    hw_index, hw_index, (uint64_t)m_state.dbg.__wvr[hw_index],
969                    hw_index, (uint64_t)m_state.dbg.__wcr[hw_index]);
970 
971   // The kernel will set the MDE_ENABLE bit in the MDSCR_EL1 for us
972   // automatically, don't need to do it here.
973 
974   kret = SetDBGState(false);
975 
976   return (kret == KERN_SUCCESS);
977 }
978 
979 bool DNBArchMachARM64::DisableHardwareWatchpoint(uint32_t hw_index,
980                                                  bool also_set_on_task) {
981   if (hw_index < NumSupportedHardwareWatchpoints() && LoHi[hw_index]) {
982     return DisableHardwareWatchpoint_helper(hw_index, also_set_on_task) &&
983            DisableHardwareWatchpoint_helper(LoHi[hw_index], also_set_on_task);
984   } else {
985     return DisableHardwareWatchpoint_helper(hw_index, also_set_on_task);
986   }
987 }
988 
989 bool DNBArchMachARM64::DisableHardwareWatchpoint_helper(uint32_t hw_index,
990                                                         bool also_set_on_task) {
991   kern_return_t kret = GetDBGState(false);
992   if (kret != KERN_SUCCESS)
993     return false;
994 
995   const uint32_t num_hw_points = NumSupportedHardwareWatchpoints();
996   if (hw_index >= num_hw_points)
997     return false;
998 
999   m_disabled_watchpoints[hw_index].addr = m_state.dbg.__wvr[hw_index];
1000   m_disabled_watchpoints[hw_index].control = m_state.dbg.__wcr[hw_index];
1001 
1002   m_state.dbg.__wcr[hw_index] &= ~((nub_addr_t)WCR_ENABLE);
1003   DNBLogThreadedIf(LOG_WATCHPOINTS, "DNBArchMachARM64::"
1004                                     "DisableHardwareWatchpoint( %u ) - WVR%u = "
1005                                     "0x%8.8llx  WCR%u = 0x%8.8llx",
1006                    hw_index, hw_index, (uint64_t)m_state.dbg.__wvr[hw_index],
1007                    hw_index, (uint64_t)m_state.dbg.__wcr[hw_index]);
1008 
1009   kret = SetDBGState(also_set_on_task);
1010 
1011   return (kret == KERN_SUCCESS);
1012 }
1013 
1014 bool DNBArchMachARM64::DisableHardwareBreakpoint(uint32_t hw_index,
1015                                                  bool also_set_on_task) {
1016   kern_return_t kret = GetDBGState(false);
1017   if (kret != KERN_SUCCESS)
1018     return false;
1019 
1020   const uint32_t num_hw_points = NumSupportedHardwareBreakpoints();
1021   if (hw_index >= num_hw_points)
1022     return false;
1023 
1024   m_disabled_breakpoints[hw_index].addr = m_state.dbg.__bvr[hw_index];
1025   m_disabled_breakpoints[hw_index].control = m_state.dbg.__bcr[hw_index];
1026 
1027   m_state.dbg.__bcr[hw_index] = 0;
1028   DNBLogThreadedIf(LOG_WATCHPOINTS,
1029                    "DNBArchMachARM64::"
1030                    "DisableHardwareBreakpoint( %u ) - WVR%u = "
1031                    "0x%8.8llx  BCR%u = 0x%8.8llx",
1032                    hw_index, hw_index, (uint64_t)m_state.dbg.__bvr[hw_index],
1033                    hw_index, (uint64_t)m_state.dbg.__bcr[hw_index]);
1034 
1035   kret = SetDBGState(also_set_on_task);
1036 
1037   return (kret == KERN_SUCCESS);
1038 }
1039 
1040 // This is for checking the Byte Address Select bits in the DBRWCRn_EL1 control
1041 // register.
1042 // Returns -1 if the trailing bit patterns are not one of:
1043 // { 0b???????1, 0b??????10, 0b?????100, 0b????1000, 0b???10000, 0b??100000,
1044 // 0b?1000000, 0b10000000 }.
1045 static inline int32_t LowestBitSet(uint32_t val) {
1046   for (unsigned i = 0; i < 8; ++i) {
1047     if (bit(val, i))
1048       return i;
1049   }
1050   return -1;
1051 }
1052 
1053 // Iterate through the debug registers; return the index of the first watchpoint
1054 // whose address matches.
1055 // As a side effect, the starting address as understood by the debugger is
1056 // returned which could be
1057 // different from 'addr' passed as an in/out argument.
1058 uint32_t DNBArchMachARM64::GetHardwareWatchpointHit(nub_addr_t &addr) {
1059   // Read the debug state
1060   kern_return_t kret = GetDBGState(true);
1061   // DumpDBGState(m_state.dbg);
1062   DNBLogThreadedIf(
1063       LOG_WATCHPOINTS,
1064       "DNBArchMachARM64::GetHardwareWatchpointHit() GetDBGState() => 0x%8.8x.",
1065       kret);
1066   DNBLogThreadedIf(LOG_WATCHPOINTS,
1067                    "DNBArchMachARM64::GetHardwareWatchpointHit() addr = 0x%llx",
1068                    (uint64_t)addr);
1069 
1070   // This is the watchpoint value to match against, i.e., word address.
1071   nub_addr_t wp_val = addr & ~((nub_addr_t)3);
1072   if (kret == KERN_SUCCESS) {
1073     DBG &debug_state = m_state.dbg;
1074     uint32_t i, num = NumSupportedHardwareWatchpoints();
1075     for (i = 0; i < num; ++i) {
1076       nub_addr_t wp_addr = GetWatchAddress(debug_state, i);
1077       DNBLogThreadedIf(LOG_WATCHPOINTS, "DNBArchMachARM64::"
1078                                         "GetHardwareWatchpointHit() slot: %u "
1079                                         "(addr = 0x%llx).",
1080                        i, (uint64_t)wp_addr);
1081       if (wp_val == wp_addr) {
1082         uint32_t byte_mask = bits(debug_state.__wcr[i], 12, 5);
1083 
1084         // Sanity check the byte_mask, first.
1085         if (LowestBitSet(byte_mask) < 0)
1086           continue;
1087 
1088         // Check that the watchpoint is enabled.
1089         if (!IsWatchpointEnabled(debug_state, i))
1090           continue;
1091 
1092         // Compute the starting address (from the point of view of the
1093         // debugger).
1094         addr = wp_addr + LowestBitSet(byte_mask);
1095         return i;
1096       }
1097     }
1098   }
1099   return INVALID_NUB_HW_INDEX;
1100 }
1101 
1102 nub_addr_t DNBArchMachARM64::GetWatchpointAddressByIndex(uint32_t hw_index) {
1103   kern_return_t kret = GetDBGState(true);
1104   if (kret != KERN_SUCCESS)
1105     return INVALID_NUB_ADDRESS;
1106   const uint32_t num = NumSupportedHardwareWatchpoints();
1107   if (hw_index >= num)
1108     return INVALID_NUB_ADDRESS;
1109   if (IsWatchpointEnabled(m_state.dbg, hw_index))
1110     return GetWatchAddress(m_state.dbg, hw_index);
1111   return INVALID_NUB_ADDRESS;
1112 }
1113 
1114 bool DNBArchMachARM64::IsWatchpointEnabled(const DBG &debug_state,
1115                                            uint32_t hw_index) {
1116   // Watchpoint Control Registers, bitfield definitions
1117   // ...
1118   // Bits    Value    Description
1119   // [0]     0        Watchpoint disabled
1120   //         1        Watchpoint enabled.
1121   return (debug_state.__wcr[hw_index] & 1u);
1122 }
1123 
1124 nub_addr_t DNBArchMachARM64::GetWatchAddress(const DBG &debug_state,
1125                                              uint32_t hw_index) {
1126   // Watchpoint Value Registers, bitfield definitions
1127   // Bits        Description
1128   // [31:2]      Watchpoint value (word address, i.e., 4-byte aligned)
1129   // [1:0]       RAZ/SBZP
1130   return bits(debug_state.__wvr[hw_index], 63, 0);
1131 }
1132 
1133 // Register information definitions for 64 bit ARMv8.
1134 enum gpr_regnums {
1135   gpr_x0 = 0,
1136   gpr_x1,
1137   gpr_x2,
1138   gpr_x3,
1139   gpr_x4,
1140   gpr_x5,
1141   gpr_x6,
1142   gpr_x7,
1143   gpr_x8,
1144   gpr_x9,
1145   gpr_x10,
1146   gpr_x11,
1147   gpr_x12,
1148   gpr_x13,
1149   gpr_x14,
1150   gpr_x15,
1151   gpr_x16,
1152   gpr_x17,
1153   gpr_x18,
1154   gpr_x19,
1155   gpr_x20,
1156   gpr_x21,
1157   gpr_x22,
1158   gpr_x23,
1159   gpr_x24,
1160   gpr_x25,
1161   gpr_x26,
1162   gpr_x27,
1163   gpr_x28,
1164   gpr_fp,
1165   gpr_x29 = gpr_fp,
1166   gpr_lr,
1167   gpr_x30 = gpr_lr,
1168   gpr_sp,
1169   gpr_x31 = gpr_sp,
1170   gpr_pc,
1171   gpr_cpsr,
1172   gpr_w0,
1173   gpr_w1,
1174   gpr_w2,
1175   gpr_w3,
1176   gpr_w4,
1177   gpr_w5,
1178   gpr_w6,
1179   gpr_w7,
1180   gpr_w8,
1181   gpr_w9,
1182   gpr_w10,
1183   gpr_w11,
1184   gpr_w12,
1185   gpr_w13,
1186   gpr_w14,
1187   gpr_w15,
1188   gpr_w16,
1189   gpr_w17,
1190   gpr_w18,
1191   gpr_w19,
1192   gpr_w20,
1193   gpr_w21,
1194   gpr_w22,
1195   gpr_w23,
1196   gpr_w24,
1197   gpr_w25,
1198   gpr_w26,
1199   gpr_w27,
1200   gpr_w28
1201 
1202 };
1203 
1204 enum {
1205   vfp_v0 = 0,
1206   vfp_v1,
1207   vfp_v2,
1208   vfp_v3,
1209   vfp_v4,
1210   vfp_v5,
1211   vfp_v6,
1212   vfp_v7,
1213   vfp_v8,
1214   vfp_v9,
1215   vfp_v10,
1216   vfp_v11,
1217   vfp_v12,
1218   vfp_v13,
1219   vfp_v14,
1220   vfp_v15,
1221   vfp_v16,
1222   vfp_v17,
1223   vfp_v18,
1224   vfp_v19,
1225   vfp_v20,
1226   vfp_v21,
1227   vfp_v22,
1228   vfp_v23,
1229   vfp_v24,
1230   vfp_v25,
1231   vfp_v26,
1232   vfp_v27,
1233   vfp_v28,
1234   vfp_v29,
1235   vfp_v30,
1236   vfp_v31,
1237   vfp_fpsr,
1238   vfp_fpcr,
1239 
1240   // lower 32 bits of the corresponding vfp_v<n> reg.
1241   vfp_s0,
1242   vfp_s1,
1243   vfp_s2,
1244   vfp_s3,
1245   vfp_s4,
1246   vfp_s5,
1247   vfp_s6,
1248   vfp_s7,
1249   vfp_s8,
1250   vfp_s9,
1251   vfp_s10,
1252   vfp_s11,
1253   vfp_s12,
1254   vfp_s13,
1255   vfp_s14,
1256   vfp_s15,
1257   vfp_s16,
1258   vfp_s17,
1259   vfp_s18,
1260   vfp_s19,
1261   vfp_s20,
1262   vfp_s21,
1263   vfp_s22,
1264   vfp_s23,
1265   vfp_s24,
1266   vfp_s25,
1267   vfp_s26,
1268   vfp_s27,
1269   vfp_s28,
1270   vfp_s29,
1271   vfp_s30,
1272   vfp_s31,
1273 
1274   // lower 64 bits of the corresponding vfp_v<n> reg.
1275   vfp_d0,
1276   vfp_d1,
1277   vfp_d2,
1278   vfp_d3,
1279   vfp_d4,
1280   vfp_d5,
1281   vfp_d6,
1282   vfp_d7,
1283   vfp_d8,
1284   vfp_d9,
1285   vfp_d10,
1286   vfp_d11,
1287   vfp_d12,
1288   vfp_d13,
1289   vfp_d14,
1290   vfp_d15,
1291   vfp_d16,
1292   vfp_d17,
1293   vfp_d18,
1294   vfp_d19,
1295   vfp_d20,
1296   vfp_d21,
1297   vfp_d22,
1298   vfp_d23,
1299   vfp_d24,
1300   vfp_d25,
1301   vfp_d26,
1302   vfp_d27,
1303   vfp_d28,
1304   vfp_d29,
1305   vfp_d30,
1306   vfp_d31
1307 };
1308 
1309 enum { exc_far = 0, exc_esr, exc_exception };
1310 
1311 // These numbers from the "DWARF for the ARM 64-bit Architecture (AArch64)"
1312 // document.
1313 
1314 enum {
1315   dwarf_x0 = 0,
1316   dwarf_x1,
1317   dwarf_x2,
1318   dwarf_x3,
1319   dwarf_x4,
1320   dwarf_x5,
1321   dwarf_x6,
1322   dwarf_x7,
1323   dwarf_x8,
1324   dwarf_x9,
1325   dwarf_x10,
1326   dwarf_x11,
1327   dwarf_x12,
1328   dwarf_x13,
1329   dwarf_x14,
1330   dwarf_x15,
1331   dwarf_x16,
1332   dwarf_x17,
1333   dwarf_x18,
1334   dwarf_x19,
1335   dwarf_x20,
1336   dwarf_x21,
1337   dwarf_x22,
1338   dwarf_x23,
1339   dwarf_x24,
1340   dwarf_x25,
1341   dwarf_x26,
1342   dwarf_x27,
1343   dwarf_x28,
1344   dwarf_x29,
1345   dwarf_x30,
1346   dwarf_x31,
1347   dwarf_pc = 32,
1348   dwarf_elr_mode = 33,
1349   dwarf_fp = dwarf_x29,
1350   dwarf_lr = dwarf_x30,
1351   dwarf_sp = dwarf_x31,
1352   // 34-63 reserved
1353 
1354   // V0-V31 (128 bit vector registers)
1355   dwarf_v0 = 64,
1356   dwarf_v1,
1357   dwarf_v2,
1358   dwarf_v3,
1359   dwarf_v4,
1360   dwarf_v5,
1361   dwarf_v6,
1362   dwarf_v7,
1363   dwarf_v8,
1364   dwarf_v9,
1365   dwarf_v10,
1366   dwarf_v11,
1367   dwarf_v12,
1368   dwarf_v13,
1369   dwarf_v14,
1370   dwarf_v15,
1371   dwarf_v16,
1372   dwarf_v17,
1373   dwarf_v18,
1374   dwarf_v19,
1375   dwarf_v20,
1376   dwarf_v21,
1377   dwarf_v22,
1378   dwarf_v23,
1379   dwarf_v24,
1380   dwarf_v25,
1381   dwarf_v26,
1382   dwarf_v27,
1383   dwarf_v28,
1384   dwarf_v29,
1385   dwarf_v30,
1386   dwarf_v31
1387 
1388   // 96-127 reserved
1389 };
1390 
1391 enum {
1392   debugserver_gpr_x0 = 0,
1393   debugserver_gpr_x1,
1394   debugserver_gpr_x2,
1395   debugserver_gpr_x3,
1396   debugserver_gpr_x4,
1397   debugserver_gpr_x5,
1398   debugserver_gpr_x6,
1399   debugserver_gpr_x7,
1400   debugserver_gpr_x8,
1401   debugserver_gpr_x9,
1402   debugserver_gpr_x10,
1403   debugserver_gpr_x11,
1404   debugserver_gpr_x12,
1405   debugserver_gpr_x13,
1406   debugserver_gpr_x14,
1407   debugserver_gpr_x15,
1408   debugserver_gpr_x16,
1409   debugserver_gpr_x17,
1410   debugserver_gpr_x18,
1411   debugserver_gpr_x19,
1412   debugserver_gpr_x20,
1413   debugserver_gpr_x21,
1414   debugserver_gpr_x22,
1415   debugserver_gpr_x23,
1416   debugserver_gpr_x24,
1417   debugserver_gpr_x25,
1418   debugserver_gpr_x26,
1419   debugserver_gpr_x27,
1420   debugserver_gpr_x28,
1421   debugserver_gpr_fp, // x29
1422   debugserver_gpr_lr, // x30
1423   debugserver_gpr_sp, // sp aka xsp
1424   debugserver_gpr_pc,
1425   debugserver_gpr_cpsr,
1426   debugserver_vfp_v0,
1427   debugserver_vfp_v1,
1428   debugserver_vfp_v2,
1429   debugserver_vfp_v3,
1430   debugserver_vfp_v4,
1431   debugserver_vfp_v5,
1432   debugserver_vfp_v6,
1433   debugserver_vfp_v7,
1434   debugserver_vfp_v8,
1435   debugserver_vfp_v9,
1436   debugserver_vfp_v10,
1437   debugserver_vfp_v11,
1438   debugserver_vfp_v12,
1439   debugserver_vfp_v13,
1440   debugserver_vfp_v14,
1441   debugserver_vfp_v15,
1442   debugserver_vfp_v16,
1443   debugserver_vfp_v17,
1444   debugserver_vfp_v18,
1445   debugserver_vfp_v19,
1446   debugserver_vfp_v20,
1447   debugserver_vfp_v21,
1448   debugserver_vfp_v22,
1449   debugserver_vfp_v23,
1450   debugserver_vfp_v24,
1451   debugserver_vfp_v25,
1452   debugserver_vfp_v26,
1453   debugserver_vfp_v27,
1454   debugserver_vfp_v28,
1455   debugserver_vfp_v29,
1456   debugserver_vfp_v30,
1457   debugserver_vfp_v31,
1458   debugserver_vfp_fpsr,
1459   debugserver_vfp_fpcr
1460 };
1461 
1462 const char *g_contained_x0[]{"x0", NULL};
1463 const char *g_contained_x1[]{"x1", NULL};
1464 const char *g_contained_x2[]{"x2", NULL};
1465 const char *g_contained_x3[]{"x3", NULL};
1466 const char *g_contained_x4[]{"x4", NULL};
1467 const char *g_contained_x5[]{"x5", NULL};
1468 const char *g_contained_x6[]{"x6", NULL};
1469 const char *g_contained_x7[]{"x7", NULL};
1470 const char *g_contained_x8[]{"x8", NULL};
1471 const char *g_contained_x9[]{"x9", NULL};
1472 const char *g_contained_x10[]{"x10", NULL};
1473 const char *g_contained_x11[]{"x11", NULL};
1474 const char *g_contained_x12[]{"x12", NULL};
1475 const char *g_contained_x13[]{"x13", NULL};
1476 const char *g_contained_x14[]{"x14", NULL};
1477 const char *g_contained_x15[]{"x15", NULL};
1478 const char *g_contained_x16[]{"x16", NULL};
1479 const char *g_contained_x17[]{"x17", NULL};
1480 const char *g_contained_x18[]{"x18", NULL};
1481 const char *g_contained_x19[]{"x19", NULL};
1482 const char *g_contained_x20[]{"x20", NULL};
1483 const char *g_contained_x21[]{"x21", NULL};
1484 const char *g_contained_x22[]{"x22", NULL};
1485 const char *g_contained_x23[]{"x23", NULL};
1486 const char *g_contained_x24[]{"x24", NULL};
1487 const char *g_contained_x25[]{"x25", NULL};
1488 const char *g_contained_x26[]{"x26", NULL};
1489 const char *g_contained_x27[]{"x27", NULL};
1490 const char *g_contained_x28[]{"x28", NULL};
1491 
1492 const char *g_invalidate_x0[]{"x0", "w0", NULL};
1493 const char *g_invalidate_x1[]{"x1", "w1", NULL};
1494 const char *g_invalidate_x2[]{"x2", "w2", NULL};
1495 const char *g_invalidate_x3[]{"x3", "w3", NULL};
1496 const char *g_invalidate_x4[]{"x4", "w4", NULL};
1497 const char *g_invalidate_x5[]{"x5", "w5", NULL};
1498 const char *g_invalidate_x6[]{"x6", "w6", NULL};
1499 const char *g_invalidate_x7[]{"x7", "w7", NULL};
1500 const char *g_invalidate_x8[]{"x8", "w8", NULL};
1501 const char *g_invalidate_x9[]{"x9", "w9", NULL};
1502 const char *g_invalidate_x10[]{"x10", "w10", NULL};
1503 const char *g_invalidate_x11[]{"x11", "w11", NULL};
1504 const char *g_invalidate_x12[]{"x12", "w12", NULL};
1505 const char *g_invalidate_x13[]{"x13", "w13", NULL};
1506 const char *g_invalidate_x14[]{"x14", "w14", NULL};
1507 const char *g_invalidate_x15[]{"x15", "w15", NULL};
1508 const char *g_invalidate_x16[]{"x16", "w16", NULL};
1509 const char *g_invalidate_x17[]{"x17", "w17", NULL};
1510 const char *g_invalidate_x18[]{"x18", "w18", NULL};
1511 const char *g_invalidate_x19[]{"x19", "w19", NULL};
1512 const char *g_invalidate_x20[]{"x20", "w20", NULL};
1513 const char *g_invalidate_x21[]{"x21", "w21", NULL};
1514 const char *g_invalidate_x22[]{"x22", "w22", NULL};
1515 const char *g_invalidate_x23[]{"x23", "w23", NULL};
1516 const char *g_invalidate_x24[]{"x24", "w24", NULL};
1517 const char *g_invalidate_x25[]{"x25", "w25", NULL};
1518 const char *g_invalidate_x26[]{"x26", "w26", NULL};
1519 const char *g_invalidate_x27[]{"x27", "w27", NULL};
1520 const char *g_invalidate_x28[]{"x28", "w28", NULL};
1521 
1522 #define GPR_OFFSET_IDX(idx) (offsetof(DNBArchMachARM64::GPR, __x[idx]))
1523 
1524 #define GPR_OFFSET_NAME(reg) (offsetof(DNBArchMachARM64::GPR, __##reg))
1525 
1526 // These macros will auto define the register name, alt name, register size,
1527 // register offset, encoding, format and native register. This ensures that
1528 // the register state structures are defined correctly and have the correct
1529 // sizes and offsets.
1530 #define DEFINE_GPR_IDX(idx, reg, alt, gen)                                     \
1531   {                                                                            \
1532     e_regSetGPR, gpr_##reg, #reg, alt, Uint, Hex, 8, GPR_OFFSET_IDX(idx),      \
1533         dwarf_##reg, dwarf_##reg, gen, debugserver_gpr_##reg, NULL,            \
1534         g_invalidate_x##idx                                                    \
1535   }
1536 #define DEFINE_GPR_NAME(reg, alt, gen)                                         \
1537   {                                                                            \
1538     e_regSetGPR, gpr_##reg, #reg, alt, Uint, Hex, 8, GPR_OFFSET_NAME(reg),     \
1539         dwarf_##reg, dwarf_##reg, gen, debugserver_gpr_##reg, NULL, NULL       \
1540   }
1541 #define DEFINE_PSEUDO_GPR_IDX(idx, reg)                                        \
1542   {                                                                            \
1543     e_regSetGPR, gpr_##reg, #reg, NULL, Uint, Hex, 4, 0, INVALID_NUB_REGNUM,   \
1544         INVALID_NUB_REGNUM, INVALID_NUB_REGNUM, INVALID_NUB_REGNUM,            \
1545         g_contained_x##idx, g_invalidate_x##idx                                \
1546   }
1547 
1548 //_STRUCT_ARM_THREAD_STATE64
1549 //{
1550 //	uint64_t    x[29];	/* General purpose registers x0-x28 */
1551 //	uint64_t    fp;		/* Frame pointer x29 */
1552 //	uint64_t    lr;		/* Link register x30 */
1553 //	uint64_t    sp;		/* Stack pointer x31 */
1554 //	uint64_t    pc;		/* Program counter */
1555 //	uint32_t    cpsr;	/* Current program status register */
1556 //};
1557 
1558 // General purpose registers
1559 const DNBRegisterInfo DNBArchMachARM64::g_gpr_registers[] = {
1560     DEFINE_GPR_IDX(0, x0, "arg1", GENERIC_REGNUM_ARG1),
1561     DEFINE_GPR_IDX(1, x1, "arg2", GENERIC_REGNUM_ARG2),
1562     DEFINE_GPR_IDX(2, x2, "arg3", GENERIC_REGNUM_ARG3),
1563     DEFINE_GPR_IDX(3, x3, "arg4", GENERIC_REGNUM_ARG4),
1564     DEFINE_GPR_IDX(4, x4, "arg5", GENERIC_REGNUM_ARG5),
1565     DEFINE_GPR_IDX(5, x5, "arg6", GENERIC_REGNUM_ARG6),
1566     DEFINE_GPR_IDX(6, x6, "arg7", GENERIC_REGNUM_ARG7),
1567     DEFINE_GPR_IDX(7, x7, "arg8", GENERIC_REGNUM_ARG8),
1568     DEFINE_GPR_IDX(8, x8, NULL, INVALID_NUB_REGNUM),
1569     DEFINE_GPR_IDX(9, x9, NULL, INVALID_NUB_REGNUM),
1570     DEFINE_GPR_IDX(10, x10, NULL, INVALID_NUB_REGNUM),
1571     DEFINE_GPR_IDX(11, x11, NULL, INVALID_NUB_REGNUM),
1572     DEFINE_GPR_IDX(12, x12, NULL, INVALID_NUB_REGNUM),
1573     DEFINE_GPR_IDX(13, x13, NULL, INVALID_NUB_REGNUM),
1574     DEFINE_GPR_IDX(14, x14, NULL, INVALID_NUB_REGNUM),
1575     DEFINE_GPR_IDX(15, x15, NULL, INVALID_NUB_REGNUM),
1576     DEFINE_GPR_IDX(16, x16, NULL, INVALID_NUB_REGNUM),
1577     DEFINE_GPR_IDX(17, x17, NULL, INVALID_NUB_REGNUM),
1578     DEFINE_GPR_IDX(18, x18, NULL, INVALID_NUB_REGNUM),
1579     DEFINE_GPR_IDX(19, x19, NULL, INVALID_NUB_REGNUM),
1580     DEFINE_GPR_IDX(20, x20, NULL, INVALID_NUB_REGNUM),
1581     DEFINE_GPR_IDX(21, x21, NULL, INVALID_NUB_REGNUM),
1582     DEFINE_GPR_IDX(22, x22, NULL, INVALID_NUB_REGNUM),
1583     DEFINE_GPR_IDX(23, x23, NULL, INVALID_NUB_REGNUM),
1584     DEFINE_GPR_IDX(24, x24, NULL, INVALID_NUB_REGNUM),
1585     DEFINE_GPR_IDX(25, x25, NULL, INVALID_NUB_REGNUM),
1586     DEFINE_GPR_IDX(26, x26, NULL, INVALID_NUB_REGNUM),
1587     DEFINE_GPR_IDX(27, x27, NULL, INVALID_NUB_REGNUM),
1588     DEFINE_GPR_IDX(28, x28, NULL, INVALID_NUB_REGNUM),
1589     // For the G/g packet we want to show where the offset into the regctx
1590     // is for fp/lr/sp/pc, but we cannot directly access them on arm64e
1591     // devices (and therefore can't offsetof() them)) - add the offset based
1592     // on the last accessible register by hand for advertising the location
1593     // in the regctx to lldb.  We'll go through the accessor functions when
1594     // we read/write them here.
1595     {
1596        e_regSetGPR, gpr_fp, "fp", "x29", Uint, Hex, 8, GPR_OFFSET_IDX(28) + 8,
1597        dwarf_fp, dwarf_fp, GENERIC_REGNUM_FP, debugserver_gpr_fp, NULL, NULL
1598     },
1599     {
1600        e_regSetGPR, gpr_lr, "lr", "x30", Uint, Hex, 8, GPR_OFFSET_IDX(28) + 16,
1601        dwarf_lr, dwarf_lr, GENERIC_REGNUM_RA, debugserver_gpr_lr, NULL, NULL
1602     },
1603     {
1604        e_regSetGPR, gpr_sp, "sp", "xsp", Uint, Hex, 8, GPR_OFFSET_IDX(28) + 24,
1605        dwarf_sp, dwarf_sp, GENERIC_REGNUM_SP, debugserver_gpr_sp, NULL, NULL
1606     },
1607     {
1608        e_regSetGPR, gpr_pc, "pc", NULL, Uint, Hex, 8, GPR_OFFSET_IDX(28) + 32,
1609        dwarf_pc, dwarf_pc, GENERIC_REGNUM_PC, debugserver_gpr_pc, NULL, NULL
1610     },
1611 
1612     // in armv7 we specify that writing to the CPSR should invalidate r8-12, sp,
1613     // lr.
1614     // this should be specified for arm64 too even though debugserver is only
1615     // used for
1616     // userland debugging.
1617     {e_regSetGPR, gpr_cpsr, "cpsr", "flags", Uint, Hex, 4,
1618      GPR_OFFSET_NAME(cpsr), dwarf_elr_mode, dwarf_elr_mode, INVALID_NUB_REGNUM,
1619      debugserver_gpr_cpsr, NULL, NULL},
1620 
1621     DEFINE_PSEUDO_GPR_IDX(0, w0),
1622     DEFINE_PSEUDO_GPR_IDX(1, w1),
1623     DEFINE_PSEUDO_GPR_IDX(2, w2),
1624     DEFINE_PSEUDO_GPR_IDX(3, w3),
1625     DEFINE_PSEUDO_GPR_IDX(4, w4),
1626     DEFINE_PSEUDO_GPR_IDX(5, w5),
1627     DEFINE_PSEUDO_GPR_IDX(6, w6),
1628     DEFINE_PSEUDO_GPR_IDX(7, w7),
1629     DEFINE_PSEUDO_GPR_IDX(8, w8),
1630     DEFINE_PSEUDO_GPR_IDX(9, w9),
1631     DEFINE_PSEUDO_GPR_IDX(10, w10),
1632     DEFINE_PSEUDO_GPR_IDX(11, w11),
1633     DEFINE_PSEUDO_GPR_IDX(12, w12),
1634     DEFINE_PSEUDO_GPR_IDX(13, w13),
1635     DEFINE_PSEUDO_GPR_IDX(14, w14),
1636     DEFINE_PSEUDO_GPR_IDX(15, w15),
1637     DEFINE_PSEUDO_GPR_IDX(16, w16),
1638     DEFINE_PSEUDO_GPR_IDX(17, w17),
1639     DEFINE_PSEUDO_GPR_IDX(18, w18),
1640     DEFINE_PSEUDO_GPR_IDX(19, w19),
1641     DEFINE_PSEUDO_GPR_IDX(20, w20),
1642     DEFINE_PSEUDO_GPR_IDX(21, w21),
1643     DEFINE_PSEUDO_GPR_IDX(22, w22),
1644     DEFINE_PSEUDO_GPR_IDX(23, w23),
1645     DEFINE_PSEUDO_GPR_IDX(24, w24),
1646     DEFINE_PSEUDO_GPR_IDX(25, w25),
1647     DEFINE_PSEUDO_GPR_IDX(26, w26),
1648     DEFINE_PSEUDO_GPR_IDX(27, w27),
1649     DEFINE_PSEUDO_GPR_IDX(28, w28)};
1650 
1651 const char *g_contained_v0[]{"v0", NULL};
1652 const char *g_contained_v1[]{"v1", NULL};
1653 const char *g_contained_v2[]{"v2", NULL};
1654 const char *g_contained_v3[]{"v3", NULL};
1655 const char *g_contained_v4[]{"v4", NULL};
1656 const char *g_contained_v5[]{"v5", NULL};
1657 const char *g_contained_v6[]{"v6", NULL};
1658 const char *g_contained_v7[]{"v7", NULL};
1659 const char *g_contained_v8[]{"v8", NULL};
1660 const char *g_contained_v9[]{"v9", NULL};
1661 const char *g_contained_v10[]{"v10", NULL};
1662 const char *g_contained_v11[]{"v11", NULL};
1663 const char *g_contained_v12[]{"v12", NULL};
1664 const char *g_contained_v13[]{"v13", NULL};
1665 const char *g_contained_v14[]{"v14", NULL};
1666 const char *g_contained_v15[]{"v15", NULL};
1667 const char *g_contained_v16[]{"v16", NULL};
1668 const char *g_contained_v17[]{"v17", NULL};
1669 const char *g_contained_v18[]{"v18", NULL};
1670 const char *g_contained_v19[]{"v19", NULL};
1671 const char *g_contained_v20[]{"v20", NULL};
1672 const char *g_contained_v21[]{"v21", NULL};
1673 const char *g_contained_v22[]{"v22", NULL};
1674 const char *g_contained_v23[]{"v23", NULL};
1675 const char *g_contained_v24[]{"v24", NULL};
1676 const char *g_contained_v25[]{"v25", NULL};
1677 const char *g_contained_v26[]{"v26", NULL};
1678 const char *g_contained_v27[]{"v27", NULL};
1679 const char *g_contained_v28[]{"v28", NULL};
1680 const char *g_contained_v29[]{"v29", NULL};
1681 const char *g_contained_v30[]{"v30", NULL};
1682 const char *g_contained_v31[]{"v31", NULL};
1683 
1684 const char *g_invalidate_v0[]{"v0", "d0", "s0", NULL};
1685 const char *g_invalidate_v1[]{"v1", "d1", "s1", NULL};
1686 const char *g_invalidate_v2[]{"v2", "d2", "s2", NULL};
1687 const char *g_invalidate_v3[]{"v3", "d3", "s3", NULL};
1688 const char *g_invalidate_v4[]{"v4", "d4", "s4", NULL};
1689 const char *g_invalidate_v5[]{"v5", "d5", "s5", NULL};
1690 const char *g_invalidate_v6[]{"v6", "d6", "s6", NULL};
1691 const char *g_invalidate_v7[]{"v7", "d7", "s7", NULL};
1692 const char *g_invalidate_v8[]{"v8", "d8", "s8", NULL};
1693 const char *g_invalidate_v9[]{"v9", "d9", "s9", NULL};
1694 const char *g_invalidate_v10[]{"v10", "d10", "s10", NULL};
1695 const char *g_invalidate_v11[]{"v11", "d11", "s11", NULL};
1696 const char *g_invalidate_v12[]{"v12", "d12", "s12", NULL};
1697 const char *g_invalidate_v13[]{"v13", "d13", "s13", NULL};
1698 const char *g_invalidate_v14[]{"v14", "d14", "s14", NULL};
1699 const char *g_invalidate_v15[]{"v15", "d15", "s15", NULL};
1700 const char *g_invalidate_v16[]{"v16", "d16", "s16", NULL};
1701 const char *g_invalidate_v17[]{"v17", "d17", "s17", NULL};
1702 const char *g_invalidate_v18[]{"v18", "d18", "s18", NULL};
1703 const char *g_invalidate_v19[]{"v19", "d19", "s19", NULL};
1704 const char *g_invalidate_v20[]{"v20", "d20", "s20", NULL};
1705 const char *g_invalidate_v21[]{"v21", "d21", "s21", NULL};
1706 const char *g_invalidate_v22[]{"v22", "d22", "s22", NULL};
1707 const char *g_invalidate_v23[]{"v23", "d23", "s23", NULL};
1708 const char *g_invalidate_v24[]{"v24", "d24", "s24", NULL};
1709 const char *g_invalidate_v25[]{"v25", "d25", "s25", NULL};
1710 const char *g_invalidate_v26[]{"v26", "d26", "s26", NULL};
1711 const char *g_invalidate_v27[]{"v27", "d27", "s27", NULL};
1712 const char *g_invalidate_v28[]{"v28", "d28", "s28", NULL};
1713 const char *g_invalidate_v29[]{"v29", "d29", "s29", NULL};
1714 const char *g_invalidate_v30[]{"v30", "d30", "s30", NULL};
1715 const char *g_invalidate_v31[]{"v31", "d31", "s31", NULL};
1716 
1717 #if defined(__arm64__) || defined(__aarch64__)
1718 #define VFP_V_OFFSET_IDX(idx)                                                  \
1719   (offsetof(DNBArchMachARM64::FPU, __v) + (idx * 16) +                         \
1720    offsetof(DNBArchMachARM64::Context, vfp))
1721 #else
1722 #define VFP_V_OFFSET_IDX(idx)                                                  \
1723   (offsetof(DNBArchMachARM64::FPU, opaque) + (idx * 16) +                      \
1724    offsetof(DNBArchMachARM64::Context, vfp))
1725 #endif
1726 #define VFP_OFFSET_NAME(reg)                                                   \
1727   (offsetof(DNBArchMachARM64::FPU, reg) +                                      \
1728    offsetof(DNBArchMachARM64::Context, vfp))
1729 #define EXC_OFFSET(reg)                                                        \
1730   (offsetof(DNBArchMachARM64::EXC, reg) +                                      \
1731    offsetof(DNBArchMachARM64::Context, exc))
1732 
1733 //#define FLOAT_FORMAT Float
1734 #define DEFINE_VFP_V_IDX(idx)                                                  \
1735   {                                                                            \
1736     e_regSetVFP, vfp_v##idx, "v" #idx, "q" #idx, Vector, VectorOfUInt8, 16,    \
1737         VFP_V_OFFSET_IDX(idx), INVALID_NUB_REGNUM, dwarf_v##idx,               \
1738         INVALID_NUB_REGNUM, debugserver_vfp_v##idx, NULL, g_invalidate_v##idx  \
1739   }
1740 #define DEFINE_PSEUDO_VFP_S_IDX(idx)                                           \
1741   {                                                                            \
1742     e_regSetVFP, vfp_s##idx, "s" #idx, NULL, IEEE754, Float, 4, 0,             \
1743         INVALID_NUB_REGNUM, INVALID_NUB_REGNUM, INVALID_NUB_REGNUM,            \
1744         INVALID_NUB_REGNUM, g_contained_v##idx, g_invalidate_v##idx            \
1745   }
1746 #define DEFINE_PSEUDO_VFP_D_IDX(idx)                                           \
1747   {                                                                            \
1748     e_regSetVFP, vfp_d##idx, "d" #idx, NULL, IEEE754, Float, 8, 0,             \
1749         INVALID_NUB_REGNUM, INVALID_NUB_REGNUM, INVALID_NUB_REGNUM,            \
1750         INVALID_NUB_REGNUM, g_contained_v##idx, g_invalidate_v##idx            \
1751   }
1752 
1753 // Floating point registers
1754 const DNBRegisterInfo DNBArchMachARM64::g_vfp_registers[] = {
1755     DEFINE_VFP_V_IDX(0),
1756     DEFINE_VFP_V_IDX(1),
1757     DEFINE_VFP_V_IDX(2),
1758     DEFINE_VFP_V_IDX(3),
1759     DEFINE_VFP_V_IDX(4),
1760     DEFINE_VFP_V_IDX(5),
1761     DEFINE_VFP_V_IDX(6),
1762     DEFINE_VFP_V_IDX(7),
1763     DEFINE_VFP_V_IDX(8),
1764     DEFINE_VFP_V_IDX(9),
1765     DEFINE_VFP_V_IDX(10),
1766     DEFINE_VFP_V_IDX(11),
1767     DEFINE_VFP_V_IDX(12),
1768     DEFINE_VFP_V_IDX(13),
1769     DEFINE_VFP_V_IDX(14),
1770     DEFINE_VFP_V_IDX(15),
1771     DEFINE_VFP_V_IDX(16),
1772     DEFINE_VFP_V_IDX(17),
1773     DEFINE_VFP_V_IDX(18),
1774     DEFINE_VFP_V_IDX(19),
1775     DEFINE_VFP_V_IDX(20),
1776     DEFINE_VFP_V_IDX(21),
1777     DEFINE_VFP_V_IDX(22),
1778     DEFINE_VFP_V_IDX(23),
1779     DEFINE_VFP_V_IDX(24),
1780     DEFINE_VFP_V_IDX(25),
1781     DEFINE_VFP_V_IDX(26),
1782     DEFINE_VFP_V_IDX(27),
1783     DEFINE_VFP_V_IDX(28),
1784     DEFINE_VFP_V_IDX(29),
1785     DEFINE_VFP_V_IDX(30),
1786     DEFINE_VFP_V_IDX(31),
1787     {e_regSetVFP, vfp_fpsr, "fpsr", NULL, Uint, Hex, 4,
1788      VFP_V_OFFSET_IDX(32) + 0, INVALID_NUB_REGNUM, INVALID_NUB_REGNUM,
1789      INVALID_NUB_REGNUM, INVALID_NUB_REGNUM, NULL, NULL},
1790     {e_regSetVFP, vfp_fpcr, "fpcr", NULL, Uint, Hex, 4,
1791      VFP_V_OFFSET_IDX(32) + 4, INVALID_NUB_REGNUM, INVALID_NUB_REGNUM,
1792      INVALID_NUB_REGNUM, INVALID_NUB_REGNUM, NULL, NULL},
1793 
1794     DEFINE_PSEUDO_VFP_S_IDX(0),
1795     DEFINE_PSEUDO_VFP_S_IDX(1),
1796     DEFINE_PSEUDO_VFP_S_IDX(2),
1797     DEFINE_PSEUDO_VFP_S_IDX(3),
1798     DEFINE_PSEUDO_VFP_S_IDX(4),
1799     DEFINE_PSEUDO_VFP_S_IDX(5),
1800     DEFINE_PSEUDO_VFP_S_IDX(6),
1801     DEFINE_PSEUDO_VFP_S_IDX(7),
1802     DEFINE_PSEUDO_VFP_S_IDX(8),
1803     DEFINE_PSEUDO_VFP_S_IDX(9),
1804     DEFINE_PSEUDO_VFP_S_IDX(10),
1805     DEFINE_PSEUDO_VFP_S_IDX(11),
1806     DEFINE_PSEUDO_VFP_S_IDX(12),
1807     DEFINE_PSEUDO_VFP_S_IDX(13),
1808     DEFINE_PSEUDO_VFP_S_IDX(14),
1809     DEFINE_PSEUDO_VFP_S_IDX(15),
1810     DEFINE_PSEUDO_VFP_S_IDX(16),
1811     DEFINE_PSEUDO_VFP_S_IDX(17),
1812     DEFINE_PSEUDO_VFP_S_IDX(18),
1813     DEFINE_PSEUDO_VFP_S_IDX(19),
1814     DEFINE_PSEUDO_VFP_S_IDX(20),
1815     DEFINE_PSEUDO_VFP_S_IDX(21),
1816     DEFINE_PSEUDO_VFP_S_IDX(22),
1817     DEFINE_PSEUDO_VFP_S_IDX(23),
1818     DEFINE_PSEUDO_VFP_S_IDX(24),
1819     DEFINE_PSEUDO_VFP_S_IDX(25),
1820     DEFINE_PSEUDO_VFP_S_IDX(26),
1821     DEFINE_PSEUDO_VFP_S_IDX(27),
1822     DEFINE_PSEUDO_VFP_S_IDX(28),
1823     DEFINE_PSEUDO_VFP_S_IDX(29),
1824     DEFINE_PSEUDO_VFP_S_IDX(30),
1825     DEFINE_PSEUDO_VFP_S_IDX(31),
1826 
1827     DEFINE_PSEUDO_VFP_D_IDX(0),
1828     DEFINE_PSEUDO_VFP_D_IDX(1),
1829     DEFINE_PSEUDO_VFP_D_IDX(2),
1830     DEFINE_PSEUDO_VFP_D_IDX(3),
1831     DEFINE_PSEUDO_VFP_D_IDX(4),
1832     DEFINE_PSEUDO_VFP_D_IDX(5),
1833     DEFINE_PSEUDO_VFP_D_IDX(6),
1834     DEFINE_PSEUDO_VFP_D_IDX(7),
1835     DEFINE_PSEUDO_VFP_D_IDX(8),
1836     DEFINE_PSEUDO_VFP_D_IDX(9),
1837     DEFINE_PSEUDO_VFP_D_IDX(10),
1838     DEFINE_PSEUDO_VFP_D_IDX(11),
1839     DEFINE_PSEUDO_VFP_D_IDX(12),
1840     DEFINE_PSEUDO_VFP_D_IDX(13),
1841     DEFINE_PSEUDO_VFP_D_IDX(14),
1842     DEFINE_PSEUDO_VFP_D_IDX(15),
1843     DEFINE_PSEUDO_VFP_D_IDX(16),
1844     DEFINE_PSEUDO_VFP_D_IDX(17),
1845     DEFINE_PSEUDO_VFP_D_IDX(18),
1846     DEFINE_PSEUDO_VFP_D_IDX(19),
1847     DEFINE_PSEUDO_VFP_D_IDX(20),
1848     DEFINE_PSEUDO_VFP_D_IDX(21),
1849     DEFINE_PSEUDO_VFP_D_IDX(22),
1850     DEFINE_PSEUDO_VFP_D_IDX(23),
1851     DEFINE_PSEUDO_VFP_D_IDX(24),
1852     DEFINE_PSEUDO_VFP_D_IDX(25),
1853     DEFINE_PSEUDO_VFP_D_IDX(26),
1854     DEFINE_PSEUDO_VFP_D_IDX(27),
1855     DEFINE_PSEUDO_VFP_D_IDX(28),
1856     DEFINE_PSEUDO_VFP_D_IDX(29),
1857     DEFINE_PSEUDO_VFP_D_IDX(30),
1858     DEFINE_PSEUDO_VFP_D_IDX(31)
1859 
1860 };
1861 
1862 //_STRUCT_ARM_EXCEPTION_STATE64
1863 //{
1864 //	uint64_t	far; /* Virtual Fault Address */
1865 //	uint32_t	esr; /* Exception syndrome */
1866 //	uint32_t	exception; /* number of arm exception taken */
1867 //};
1868 
1869 // Exception registers
1870 const DNBRegisterInfo DNBArchMachARM64::g_exc_registers[] = {
1871     {e_regSetEXC, exc_far, "far", NULL, Uint, Hex, 8, EXC_OFFSET(__far),
1872      INVALID_NUB_REGNUM, INVALID_NUB_REGNUM, INVALID_NUB_REGNUM,
1873      INVALID_NUB_REGNUM, NULL, NULL},
1874     {e_regSetEXC, exc_esr, "esr", NULL, Uint, Hex, 4, EXC_OFFSET(__esr),
1875      INVALID_NUB_REGNUM, INVALID_NUB_REGNUM, INVALID_NUB_REGNUM,
1876      INVALID_NUB_REGNUM, NULL, NULL},
1877     {e_regSetEXC, exc_exception, "exception", NULL, Uint, Hex, 4,
1878      EXC_OFFSET(__exception), INVALID_NUB_REGNUM, INVALID_NUB_REGNUM,
1879      INVALID_NUB_REGNUM, INVALID_NUB_REGNUM, NULL, NULL}};
1880 
1881 // Number of registers in each register set
1882 const size_t DNBArchMachARM64::k_num_gpr_registers =
1883     sizeof(g_gpr_registers) / sizeof(DNBRegisterInfo);
1884 const size_t DNBArchMachARM64::k_num_vfp_registers =
1885     sizeof(g_vfp_registers) / sizeof(DNBRegisterInfo);
1886 const size_t DNBArchMachARM64::k_num_exc_registers =
1887     sizeof(g_exc_registers) / sizeof(DNBRegisterInfo);
1888 const size_t DNBArchMachARM64::k_num_all_registers =
1889     k_num_gpr_registers + k_num_vfp_registers + k_num_exc_registers;
1890 
1891 // Register set definitions. The first definitions at register set index
1892 // of zero is for all registers, followed by other registers sets. The
1893 // register information for the all register set need not be filled in.
1894 const DNBRegisterSetInfo DNBArchMachARM64::g_reg_sets[] = {
1895     {"ARM64 Registers", NULL, k_num_all_registers},
1896     {"General Purpose Registers", g_gpr_registers, k_num_gpr_registers},
1897     {"Floating Point Registers", g_vfp_registers, k_num_vfp_registers},
1898     {"Exception State Registers", g_exc_registers, k_num_exc_registers}};
1899 // Total number of register sets for this architecture
1900 const size_t DNBArchMachARM64::k_num_register_sets =
1901     sizeof(g_reg_sets) / sizeof(DNBRegisterSetInfo);
1902 
1903 const DNBRegisterSetInfo *
1904 DNBArchMachARM64::GetRegisterSetInfo(nub_size_t *num_reg_sets) {
1905   *num_reg_sets = k_num_register_sets;
1906   return g_reg_sets;
1907 }
1908 
1909 bool DNBArchMachARM64::FixGenericRegisterNumber(uint32_t &set, uint32_t &reg) {
1910   if (set == REGISTER_SET_GENERIC) {
1911     switch (reg) {
1912     case GENERIC_REGNUM_PC: // Program Counter
1913       set = e_regSetGPR;
1914       reg = gpr_pc;
1915       break;
1916 
1917     case GENERIC_REGNUM_SP: // Stack Pointer
1918       set = e_regSetGPR;
1919       reg = gpr_sp;
1920       break;
1921 
1922     case GENERIC_REGNUM_FP: // Frame Pointer
1923       set = e_regSetGPR;
1924       reg = gpr_fp;
1925       break;
1926 
1927     case GENERIC_REGNUM_RA: // Return Address
1928       set = e_regSetGPR;
1929       reg = gpr_lr;
1930       break;
1931 
1932     case GENERIC_REGNUM_FLAGS: // Processor flags register
1933       set = e_regSetGPR;
1934       reg = gpr_cpsr;
1935       break;
1936 
1937     case GENERIC_REGNUM_ARG1:
1938     case GENERIC_REGNUM_ARG2:
1939     case GENERIC_REGNUM_ARG3:
1940     case GENERIC_REGNUM_ARG4:
1941     case GENERIC_REGNUM_ARG5:
1942     case GENERIC_REGNUM_ARG6:
1943       set = e_regSetGPR;
1944       reg = gpr_x0 + reg - GENERIC_REGNUM_ARG1;
1945       break;
1946 
1947     default:
1948       return false;
1949     }
1950   }
1951   return true;
1952 }
1953 bool DNBArchMachARM64::GetRegisterValue(uint32_t set, uint32_t reg,
1954                                         DNBRegisterValue *value) {
1955   if (!FixGenericRegisterNumber(set, reg))
1956     return false;
1957 
1958   if (GetRegisterState(set, false) != KERN_SUCCESS)
1959     return false;
1960 
1961   const DNBRegisterInfo *regInfo = m_thread->GetRegisterInfo(set, reg);
1962   if (regInfo) {
1963     value->info = *regInfo;
1964     switch (set) {
1965     case e_regSetGPR:
1966       if (reg <= gpr_pc) {
1967 #if defined(__LP64__)
1968         if (reg == gpr_pc)
1969           value->value.uint64 = arm_thread_state64_get_pc (m_state.context.gpr);
1970         else if (reg == gpr_lr)
1971           value->value.uint64 = arm_thread_state64_get_lr (m_state.context.gpr);
1972         else if (reg == gpr_sp)
1973           value->value.uint64 = arm_thread_state64_get_sp (m_state.context.gpr);
1974         else if (reg == gpr_fp)
1975           value->value.uint64 = arm_thread_state64_get_fp (m_state.context.gpr);
1976         else
1977         value->value.uint64 = m_state.context.gpr.__x[reg];
1978 #else
1979         value->value.uint64 = m_state.context.gpr.__x[reg];
1980 #endif
1981         return true;
1982       } else if (reg == gpr_cpsr) {
1983         value->value.uint32 = m_state.context.gpr.__cpsr;
1984         return true;
1985       }
1986       break;
1987 
1988     case e_regSetVFP:
1989 
1990       if (reg >= vfp_v0 && reg <= vfp_v31) {
1991 #if defined(__arm64__) || defined(__aarch64__)
1992         memcpy(&value->value.v_uint8, &m_state.context.vfp.__v[reg - vfp_v0],
1993                16);
1994 #else
1995         memcpy(&value->value.v_uint8,
1996                ((uint8_t *)&m_state.context.vfp.opaque) + ((reg - vfp_v0) * 16),
1997                16);
1998 #endif
1999         return true;
2000       } else if (reg == vfp_fpsr) {
2001 #if defined(__arm64__) || defined(__aarch64__)
2002         memcpy(&value->value.uint32, &m_state.context.vfp.__fpsr, 4);
2003 #else
2004         memcpy(&value->value.uint32,
2005                ((uint8_t *)&m_state.context.vfp.opaque) + (32 * 16) + 0, 4);
2006 #endif
2007         return true;
2008       } else if (reg == vfp_fpcr) {
2009 #if defined(__arm64__) || defined(__aarch64__)
2010         memcpy(&value->value.uint32, &m_state.context.vfp.__fpcr, 4);
2011 #else
2012         memcpy(&value->value.uint32,
2013                ((uint8_t *)&m_state.context.vfp.opaque) + (32 * 16) + 4, 4);
2014 #endif
2015         return true;
2016       } else if (reg >= vfp_s0 && reg <= vfp_s31) {
2017 #if defined(__arm64__) || defined(__aarch64__)
2018         memcpy(&value->value.v_uint8, &m_state.context.vfp.__v[reg - vfp_s0],
2019                4);
2020 #else
2021         memcpy(&value->value.v_uint8,
2022                ((uint8_t *)&m_state.context.vfp.opaque) + ((reg - vfp_s0) * 16),
2023                4);
2024 #endif
2025         return true;
2026       } else if (reg >= vfp_d0 && reg <= vfp_d31) {
2027 #if defined(__arm64__) || defined(__aarch64__)
2028         memcpy(&value->value.v_uint8, &m_state.context.vfp.__v[reg - vfp_d0],
2029                8);
2030 #else
2031         memcpy(&value->value.v_uint8,
2032                ((uint8_t *)&m_state.context.vfp.opaque) + ((reg - vfp_d0) * 16),
2033                8);
2034 #endif
2035         return true;
2036       }
2037       break;
2038 
2039     case e_regSetEXC:
2040       if (reg == exc_far) {
2041         value->value.uint64 = m_state.context.exc.__far;
2042         return true;
2043       } else if (reg == exc_esr) {
2044         value->value.uint32 = m_state.context.exc.__esr;
2045         return true;
2046       } else if (reg == exc_exception) {
2047         value->value.uint32 = m_state.context.exc.__exception;
2048         return true;
2049       }
2050       break;
2051     }
2052   }
2053   return false;
2054 }
2055 
2056 bool DNBArchMachARM64::SetRegisterValue(uint32_t set, uint32_t reg,
2057                                         const DNBRegisterValue *value) {
2058   if (!FixGenericRegisterNumber(set, reg))
2059     return false;
2060 
2061   if (GetRegisterState(set, false) != KERN_SUCCESS)
2062     return false;
2063 
2064   bool success = false;
2065   const DNBRegisterInfo *regInfo = m_thread->GetRegisterInfo(set, reg);
2066   if (regInfo) {
2067     switch (set) {
2068     case e_regSetGPR:
2069       if (reg <= gpr_pc) {
2070 #if defined(__LP64__)
2071           uint64_t signed_value = value->value.uint64;
2072 #if __has_feature(ptrauth_calls)
2073           // The incoming value could be garbage.  Strip it to avoid
2074           // trapping when it gets resigned in the thread state.
2075           signed_value = (uint64_t) ptrauth_strip((void*) signed_value, ptrauth_key_function_pointer);
2076           signed_value = (uint64_t) ptrauth_sign_unauthenticated((void*) signed_value, ptrauth_key_function_pointer, 0);
2077 #endif
2078         if (reg == gpr_pc)
2079          arm_thread_state64_set_pc_fptr (m_state.context.gpr, (void*) signed_value);
2080         else if (reg == gpr_lr)
2081           arm_thread_state64_set_lr_fptr (m_state.context.gpr, (void*) signed_value);
2082         else if (reg == gpr_sp)
2083           arm_thread_state64_set_sp (m_state.context.gpr, value->value.uint64);
2084         else if (reg == gpr_fp)
2085           arm_thread_state64_set_fp (m_state.context.gpr, value->value.uint64);
2086         else
2087           m_state.context.gpr.__x[reg] = value->value.uint64;
2088 #else
2089         m_state.context.gpr.__x[reg] = value->value.uint64;
2090 #endif
2091         success = true;
2092       } else if (reg == gpr_cpsr) {
2093         m_state.context.gpr.__cpsr = value->value.uint32;
2094         success = true;
2095       }
2096       break;
2097 
2098     case e_regSetVFP:
2099       if (reg >= vfp_v0 && reg <= vfp_v31) {
2100 #if defined(__arm64__) || defined(__aarch64__)
2101         memcpy(&m_state.context.vfp.__v[reg - vfp_v0], &value->value.v_uint8,
2102                16);
2103 #else
2104         memcpy(((uint8_t *)&m_state.context.vfp.opaque) + ((reg - vfp_v0) * 16),
2105                &value->value.v_uint8, 16);
2106 #endif
2107         success = true;
2108       } else if (reg == vfp_fpsr) {
2109 #if defined(__arm64__) || defined(__aarch64__)
2110         memcpy(&m_state.context.vfp.__fpsr, &value->value.uint32, 4);
2111 #else
2112         memcpy(((uint8_t *)&m_state.context.vfp.opaque) + (32 * 16) + 0,
2113                &value->value.uint32, 4);
2114 #endif
2115         success = true;
2116       } else if (reg == vfp_fpcr) {
2117 #if defined(__arm64__) || defined(__aarch64__)
2118         memcpy(&m_state.context.vfp.__fpcr, &value->value.uint32, 4);
2119 #else
2120         memcpy(((uint8_t *)m_state.context.vfp.opaque) + (32 * 16) + 4,
2121                &value->value.uint32, 4);
2122 #endif
2123         success = true;
2124       } else if (reg >= vfp_s0 && reg <= vfp_s31) {
2125 #if defined(__arm64__) || defined(__aarch64__)
2126         memcpy(&m_state.context.vfp.__v[reg - vfp_s0], &value->value.v_uint8,
2127                4);
2128 #else
2129         memcpy(((uint8_t *)&m_state.context.vfp.opaque) + ((reg - vfp_s0) * 16),
2130                &value->value.v_uint8, 4);
2131 #endif
2132         success = true;
2133       } else if (reg >= vfp_d0 && reg <= vfp_d31) {
2134 #if defined(__arm64__) || defined(__aarch64__)
2135         memcpy(&m_state.context.vfp.__v[reg - vfp_d0], &value->value.v_uint8,
2136                8);
2137 #else
2138         memcpy(((uint8_t *)&m_state.context.vfp.opaque) + ((reg - vfp_d0) * 16),
2139                &value->value.v_uint8, 8);
2140 #endif
2141         success = true;
2142       }
2143       break;
2144 
2145     case e_regSetEXC:
2146       if (reg == exc_far) {
2147         m_state.context.exc.__far = value->value.uint64;
2148         success = true;
2149       } else if (reg == exc_esr) {
2150         m_state.context.exc.__esr = value->value.uint32;
2151         success = true;
2152       } else if (reg == exc_exception) {
2153         m_state.context.exc.__exception = value->value.uint32;
2154         success = true;
2155       }
2156       break;
2157     }
2158   }
2159   if (success)
2160     return SetRegisterState(set) == KERN_SUCCESS;
2161   return false;
2162 }
2163 
2164 kern_return_t DNBArchMachARM64::GetRegisterState(int set, bool force) {
2165   switch (set) {
2166   case e_regSetALL:
2167     return GetGPRState(force) | GetVFPState(force) | GetEXCState(force) |
2168            GetDBGState(force);
2169   case e_regSetGPR:
2170     return GetGPRState(force);
2171   case e_regSetVFP:
2172     return GetVFPState(force);
2173   case e_regSetEXC:
2174     return GetEXCState(force);
2175   case e_regSetDBG:
2176     return GetDBGState(force);
2177   default:
2178     break;
2179   }
2180   return KERN_INVALID_ARGUMENT;
2181 }
2182 
2183 kern_return_t DNBArchMachARM64::SetRegisterState(int set) {
2184   // Make sure we have a valid context to set.
2185   kern_return_t err = GetRegisterState(set, false);
2186   if (err != KERN_SUCCESS)
2187     return err;
2188 
2189   switch (set) {
2190   case e_regSetALL:
2191     return SetGPRState() | SetVFPState() | SetEXCState() | SetDBGState(false);
2192   case e_regSetGPR:
2193     return SetGPRState();
2194   case e_regSetVFP:
2195     return SetVFPState();
2196   case e_regSetEXC:
2197     return SetEXCState();
2198   case e_regSetDBG:
2199     return SetDBGState(false);
2200   default:
2201     break;
2202   }
2203   return KERN_INVALID_ARGUMENT;
2204 }
2205 
2206 bool DNBArchMachARM64::RegisterSetStateIsValid(int set) const {
2207   return m_state.RegsAreValid(set);
2208 }
2209 
2210 nub_size_t DNBArchMachARM64::GetRegisterContext(void *buf, nub_size_t buf_len) {
2211   nub_size_t size = sizeof(m_state.context.gpr) + sizeof(m_state.context.vfp) +
2212                     sizeof(m_state.context.exc);
2213 
2214   if (buf && buf_len) {
2215     if (size > buf_len)
2216       size = buf_len;
2217 
2218     bool force = false;
2219     if (GetGPRState(force) | GetVFPState(force) | GetEXCState(force))
2220       return 0;
2221 
2222     // Copy each struct individually to avoid any padding that might be between
2223     // the structs in m_state.context
2224     uint8_t *p = (uint8_t *)buf;
2225     ::memcpy(p, &m_state.context.gpr, sizeof(m_state.context.gpr));
2226     p += sizeof(m_state.context.gpr);
2227     ::memcpy(p, &m_state.context.vfp, sizeof(m_state.context.vfp));
2228     p += sizeof(m_state.context.vfp);
2229     ::memcpy(p, &m_state.context.exc, sizeof(m_state.context.exc));
2230     p += sizeof(m_state.context.exc);
2231 
2232     size_t bytes_written = p - (uint8_t *)buf;
2233     UNUSED_IF_ASSERT_DISABLED(bytes_written);
2234     assert(bytes_written == size);
2235   }
2236   DNBLogThreadedIf(
2237       LOG_THREAD,
2238       "DNBArchMachARM64::GetRegisterContext (buf = %p, len = %zu) => %zu", buf,
2239       buf_len, size);
2240   // Return the size of the register context even if NULL was passed in
2241   return size;
2242 }
2243 
2244 nub_size_t DNBArchMachARM64::SetRegisterContext(const void *buf,
2245                                                 nub_size_t buf_len) {
2246   nub_size_t size = sizeof(m_state.context.gpr) + sizeof(m_state.context.vfp) +
2247                     sizeof(m_state.context.exc);
2248 
2249   if (buf == NULL || buf_len == 0)
2250     size = 0;
2251 
2252   if (size) {
2253     if (size > buf_len)
2254       size = buf_len;
2255 
2256     // Copy each struct individually to avoid any padding that might be between
2257     // the structs in m_state.context
2258     uint8_t *p = (uint8_t *)buf;
2259     ::memcpy(&m_state.context.gpr, p, sizeof(m_state.context.gpr));
2260     p += sizeof(m_state.context.gpr);
2261     ::memcpy(&m_state.context.vfp, p, sizeof(m_state.context.vfp));
2262     p += sizeof(m_state.context.vfp);
2263     ::memcpy(&m_state.context.exc, p, sizeof(m_state.context.exc));
2264     p += sizeof(m_state.context.exc);
2265 
2266     size_t bytes_written = p - (uint8_t *)buf;
2267     UNUSED_IF_ASSERT_DISABLED(bytes_written);
2268     assert(bytes_written == size);
2269     SetGPRState();
2270     SetVFPState();
2271     SetEXCState();
2272   }
2273   DNBLogThreadedIf(
2274       LOG_THREAD,
2275       "DNBArchMachARM64::SetRegisterContext (buf = %p, len = %zu) => %zu", buf,
2276       buf_len, size);
2277   return size;
2278 }
2279 
2280 uint32_t DNBArchMachARM64::SaveRegisterState() {
2281   kern_return_t kret = ::thread_abort_safely(m_thread->MachPortNumber());
2282   DNBLogThreadedIf(
2283       LOG_THREAD, "thread = 0x%4.4x calling thread_abort_safely (tid) => %u "
2284                   "(SetGPRState() for stop_count = %u)",
2285       m_thread->MachPortNumber(), kret, m_thread->Process()->StopCount());
2286 
2287   // Always re-read the registers because above we call thread_abort_safely();
2288   bool force = true;
2289 
2290   if ((kret = GetGPRState(force)) != KERN_SUCCESS) {
2291     DNBLogThreadedIf(LOG_THREAD, "DNBArchMachARM64::SaveRegisterState () "
2292                                  "error: GPR regs failed to read: %u ",
2293                      kret);
2294   } else if ((kret = GetVFPState(force)) != KERN_SUCCESS) {
2295     DNBLogThreadedIf(LOG_THREAD, "DNBArchMachARM64::SaveRegisterState () "
2296                                  "error: %s regs failed to read: %u",
2297                      "VFP", kret);
2298   } else {
2299     const uint32_t save_id = GetNextRegisterStateSaveID();
2300     m_saved_register_states[save_id] = m_state.context;
2301     return save_id;
2302   }
2303   return UINT32_MAX;
2304 }
2305 
2306 bool DNBArchMachARM64::RestoreRegisterState(uint32_t save_id) {
2307   SaveRegisterStates::iterator pos = m_saved_register_states.find(save_id);
2308   if (pos != m_saved_register_states.end()) {
2309     m_state.context.gpr = pos->second.gpr;
2310     m_state.context.vfp = pos->second.vfp;
2311     kern_return_t kret;
2312     bool success = true;
2313     if ((kret = SetGPRState()) != KERN_SUCCESS) {
2314       DNBLogThreadedIf(LOG_THREAD, "DNBArchMachARM64::RestoreRegisterState "
2315                                    "(save_id = %u) error: GPR regs failed to "
2316                                    "write: %u",
2317                        save_id, kret);
2318       success = false;
2319     } else if ((kret = SetVFPState()) != KERN_SUCCESS) {
2320       DNBLogThreadedIf(LOG_THREAD, "DNBArchMachARM64::RestoreRegisterState "
2321                                    "(save_id = %u) error: %s regs failed to "
2322                                    "write: %u",
2323                        save_id, "VFP", kret);
2324       success = false;
2325     }
2326     m_saved_register_states.erase(pos);
2327     return success;
2328   }
2329   return false;
2330 }
2331 
2332 #endif // #if defined (ARM_THREAD_STATE64_COUNT)
2333 #endif // #if defined (__arm__) || defined (__arm64__) || defined (__aarch64__)
2334