1 //===-- DNBArchImpl.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/arm/DNBArchImpl.h"
16 #include "ARM_DWARF_Registers.h"
17 #include "ARM_ehframe_Registers.h"
18 #include "DNB.h"
19 #include "DNBBreakpoint.h"
20 #include "DNBLog.h"
21 #include "DNBRegisterInfo.h"
22 #include "MacOSX/MachProcess.h"
23 #include "MacOSX/MachThread.h"
24 
25 #include <inttypes.h>
26 #include <sys/sysctl.h>
27 
28 // BCR address match type
29 #define BCR_M_IMVA_MATCH ((uint32_t)(0u << 21))
30 #define BCR_M_CONTEXT_ID_MATCH ((uint32_t)(1u << 21))
31 #define BCR_M_IMVA_MISMATCH ((uint32_t)(2u << 21))
32 #define BCR_M_RESERVED ((uint32_t)(3u << 21))
33 
34 // Link a BVR/BCR or WVR/WCR pair to another
35 #define E_ENABLE_LINKING ((uint32_t)(1u << 20))
36 
37 // Byte Address Select
38 #define BAS_IMVA_PLUS_0 ((uint32_t)(1u << 5))
39 #define BAS_IMVA_PLUS_1 ((uint32_t)(1u << 6))
40 #define BAS_IMVA_PLUS_2 ((uint32_t)(1u << 7))
41 #define BAS_IMVA_PLUS_3 ((uint32_t)(1u << 8))
42 #define BAS_IMVA_0_1 ((uint32_t)(3u << 5))
43 #define BAS_IMVA_2_3 ((uint32_t)(3u << 7))
44 #define BAS_IMVA_ALL ((uint32_t)(0xfu << 5))
45 
46 // Break only in privileged or user mode
47 #define S_RSVD ((uint32_t)(0u << 1))
48 #define S_PRIV ((uint32_t)(1u << 1))
49 #define S_USER ((uint32_t)(2u << 1))
50 #define S_PRIV_USER ((S_PRIV) | (S_USER))
51 
52 #define BCR_ENABLE ((uint32_t)(1u))
53 #define WCR_ENABLE ((uint32_t)(1u))
54 
55 // Watchpoint load/store
56 #define WCR_LOAD ((uint32_t)(1u << 3))
57 #define WCR_STORE ((uint32_t)(1u << 4))
58 
59 // Definitions for the Debug Status and Control Register fields:
60 // [5:2] => Method of debug entry
61 //#define WATCHPOINT_OCCURRED     ((uint32_t)(2u))
62 // I'm seeing this, instead.
63 #define WATCHPOINT_OCCURRED ((uint32_t)(10u))
64 
65 // 0xE120BE70
66 static const uint8_t g_arm_breakpoint_opcode[] = {0x70, 0xBE, 0x20, 0xE1};
67 static const uint8_t g_thumb_breakpoint_opcode[] = {0x70, 0xBE};
68 
69 // A watchpoint may need to be implemented using two watchpoint registers.
70 // e.g. watching an 8-byte region when the device can only watch 4-bytes.
71 //
72 // This stores the lo->hi mappings.  It's safe to initialize to all 0's
73 // since hi > lo and therefore LoHi[i] cannot be 0.
74 static uint32_t LoHi[16] = {0};
75 
76 // ARM constants used during decoding
77 #define REG_RD 0
78 #define LDM_REGLIST 1
79 #define PC_REG 15
80 #define PC_REGLIST_BIT 0x8000
81 
82 // ARM conditions
83 #define COND_EQ 0x0
84 #define COND_NE 0x1
85 #define COND_CS 0x2
86 #define COND_HS 0x2
87 #define COND_CC 0x3
88 #define COND_LO 0x3
89 #define COND_MI 0x4
90 #define COND_PL 0x5
91 #define COND_VS 0x6
92 #define COND_VC 0x7
93 #define COND_HI 0x8
94 #define COND_LS 0x9
95 #define COND_GE 0xA
96 #define COND_LT 0xB
97 #define COND_GT 0xC
98 #define COND_LE 0xD
99 #define COND_AL 0xE
100 #define COND_UNCOND 0xF
101 
102 #define MASK_CPSR_T (1u << 5)
103 #define MASK_CPSR_J (1u << 24)
104 
105 #define MNEMONIC_STRING_SIZE 32
106 #define OPERAND_STRING_SIZE 128
107 
108 // Returns true if the first 16 bit opcode of a thumb instruction indicates
109 // the instruction will be a 32 bit thumb opcode
IsThumb32Opcode(uint16_t opcode)110 static bool IsThumb32Opcode(uint16_t opcode) {
111   if (((opcode & 0xE000) == 0xE000) && (opcode & 0x1800))
112     return true;
113   return false;
114 }
115 
Initialize()116 void DNBArchMachARM::Initialize() {
117   DNBArchPluginInfo arch_plugin_info = {
118       CPU_TYPE_ARM, DNBArchMachARM::Create, DNBArchMachARM::GetRegisterSetInfo,
119       DNBArchMachARM::SoftwareBreakpointOpcode};
120 
121   // Register this arch plug-in with the main protocol class
122   DNBArchProtocol::RegisterArchPlugin(arch_plugin_info);
123 }
124 
Create(MachThread * thread)125 DNBArchProtocol *DNBArchMachARM::Create(MachThread *thread) {
126   DNBArchMachARM *obj = new DNBArchMachARM(thread);
127   return obj;
128 }
129 
SoftwareBreakpointOpcode(nub_size_t byte_size)130 const uint8_t *DNBArchMachARM::SoftwareBreakpointOpcode(nub_size_t byte_size) {
131   switch (byte_size) {
132   case 2:
133     return g_thumb_breakpoint_opcode;
134   case 4:
135     return g_arm_breakpoint_opcode;
136   }
137   return NULL;
138 }
139 
GetCPUType()140 uint32_t DNBArchMachARM::GetCPUType() { return CPU_TYPE_ARM; }
141 
GetPC(uint64_t failValue)142 uint64_t DNBArchMachARM::GetPC(uint64_t failValue) {
143   // Get program counter
144   if (GetGPRState(false) == KERN_SUCCESS)
145     return m_state.context.gpr.__pc;
146   return failValue;
147 }
148 
SetPC(uint64_t value)149 kern_return_t DNBArchMachARM::SetPC(uint64_t value) {
150   // Get program counter
151   kern_return_t err = GetGPRState(false);
152   if (err == KERN_SUCCESS) {
153     m_state.context.gpr.__pc = (uint32_t)value;
154     err = SetGPRState();
155   }
156   return err == KERN_SUCCESS;
157 }
158 
GetSP(uint64_t failValue)159 uint64_t DNBArchMachARM::GetSP(uint64_t failValue) {
160   // Get stack pointer
161   if (GetGPRState(false) == KERN_SUCCESS)
162     return m_state.context.gpr.__sp;
163   return failValue;
164 }
165 
GetGPRState(bool force)166 kern_return_t DNBArchMachARM::GetGPRState(bool force) {
167   int set = e_regSetGPR;
168   // Check if we have valid cached registers
169   if (!force && m_state.GetError(set, Read) == KERN_SUCCESS)
170     return KERN_SUCCESS;
171 
172   // Read the registers from our thread
173   mach_msg_type_number_t count = ARM_THREAD_STATE_COUNT;
174   kern_return_t kret =
175       ::thread_get_state(m_thread->MachPortNumber(), ARM_THREAD_STATE,
176                          (thread_state_t)&m_state.context.gpr, &count);
177   uint32_t *r = &m_state.context.gpr.__r[0];
178   DNBLogThreadedIf(
179       LOG_THREAD, "thread_get_state(0x%4.4x, %u, &gpr, %u) => 0x%8.8x (count = "
180                   "%u) regs r0=%8.8x r1=%8.8x r2=%8.8x r3=%8.8x r4=%8.8x "
181                   "r5=%8.8x r6=%8.8x r7=%8.8x r8=%8.8x r9=%8.8x r10=%8.8x "
182                   "r11=%8.8x s12=%8.8x sp=%8.8x lr=%8.8x pc=%8.8x cpsr=%8.8x",
183       m_thread->MachPortNumber(), ARM_THREAD_STATE, ARM_THREAD_STATE_COUNT,
184       kret, count, r[0], r[1], r[2], r[3], r[4], r[5], r[6], r[7], r[8], r[9],
185       r[10], r[11], r[12], r[13], r[14], r[15], r[16]);
186   m_state.SetError(set, Read, kret);
187   return kret;
188 }
189 
GetVFPState(bool force)190 kern_return_t DNBArchMachARM::GetVFPState(bool force) {
191   int set = e_regSetVFP;
192   // Check if we have valid cached registers
193   if (!force && m_state.GetError(set, Read) == KERN_SUCCESS)
194     return KERN_SUCCESS;
195 
196   kern_return_t kret;
197 
198 #if defined(__arm64__) || defined(__aarch64__)
199   // Read the registers from our thread
200   mach_msg_type_number_t count = ARM_NEON_STATE_COUNT;
201   kret = ::thread_get_state(m_thread->MachPortNumber(), ARM_NEON_STATE,
202                             (thread_state_t)&m_state.context.vfp, &count);
203   if (DNBLogEnabledForAny(LOG_THREAD)) {
204     DNBLogThreaded(
205         "thread_get_state(0x%4.4x, %u, &vfp, %u) => 0x%8.8x (count = %u) regs"
206         "\n   q0  = 0x%16.16llx%16.16llx"
207         "\n   q1  = 0x%16.16llx%16.16llx"
208         "\n   q2  = 0x%16.16llx%16.16llx"
209         "\n   q3  = 0x%16.16llx%16.16llx"
210         "\n   q4  = 0x%16.16llx%16.16llx"
211         "\n   q5  = 0x%16.16llx%16.16llx"
212         "\n   q6  = 0x%16.16llx%16.16llx"
213         "\n   q7  = 0x%16.16llx%16.16llx"
214         "\n   q8  = 0x%16.16llx%16.16llx"
215         "\n   q9  = 0x%16.16llx%16.16llx"
216         "\n   q10 = 0x%16.16llx%16.16llx"
217         "\n   q11 = 0x%16.16llx%16.16llx"
218         "\n   q12 = 0x%16.16llx%16.16llx"
219         "\n   q13 = 0x%16.16llx%16.16llx"
220         "\n   q14 = 0x%16.16llx%16.16llx"
221         "\n   q15 = 0x%16.16llx%16.16llx"
222         "\n  fpsr = 0x%8.8x"
223         "\n  fpcr = 0x%8.8x\n\n",
224         m_thread->MachPortNumber(), ARM_NEON_STATE, ARM_NEON_STATE_COUNT, kret,
225         count, ((uint64_t *)&m_state.context.vfp.__v[0])[0],
226         ((uint64_t *)&m_state.context.vfp.__v[0])[1],
227         ((uint64_t *)&m_state.context.vfp.__v[1])[0],
228         ((uint64_t *)&m_state.context.vfp.__v[1])[1],
229         ((uint64_t *)&m_state.context.vfp.__v[2])[0],
230         ((uint64_t *)&m_state.context.vfp.__v[2])[1],
231         ((uint64_t *)&m_state.context.vfp.__v[3])[0],
232         ((uint64_t *)&m_state.context.vfp.__v[3])[1],
233         ((uint64_t *)&m_state.context.vfp.__v[4])[0],
234         ((uint64_t *)&m_state.context.vfp.__v[4])[1],
235         ((uint64_t *)&m_state.context.vfp.__v[5])[0],
236         ((uint64_t *)&m_state.context.vfp.__v[5])[1],
237         ((uint64_t *)&m_state.context.vfp.__v[6])[0],
238         ((uint64_t *)&m_state.context.vfp.__v[6])[1],
239         ((uint64_t *)&m_state.context.vfp.__v[7])[0],
240         ((uint64_t *)&m_state.context.vfp.__v[7])[1],
241         ((uint64_t *)&m_state.context.vfp.__v[8])[0],
242         ((uint64_t *)&m_state.context.vfp.__v[8])[1],
243         ((uint64_t *)&m_state.context.vfp.__v[9])[0],
244         ((uint64_t *)&m_state.context.vfp.__v[9])[1],
245         ((uint64_t *)&m_state.context.vfp.__v[10])[0],
246         ((uint64_t *)&m_state.context.vfp.__v[10])[1],
247         ((uint64_t *)&m_state.context.vfp.__v[11])[0],
248         ((uint64_t *)&m_state.context.vfp.__v[11])[1],
249         ((uint64_t *)&m_state.context.vfp.__v[12])[0],
250         ((uint64_t *)&m_state.context.vfp.__v[12])[1],
251         ((uint64_t *)&m_state.context.vfp.__v[13])[0],
252         ((uint64_t *)&m_state.context.vfp.__v[13])[1],
253         ((uint64_t *)&m_state.context.vfp.__v[14])[0],
254         ((uint64_t *)&m_state.context.vfp.__v[14])[1],
255         ((uint64_t *)&m_state.context.vfp.__v[15])[0],
256         ((uint64_t *)&m_state.context.vfp.__v[15])[1],
257         m_state.context.vfp.__fpsr, m_state.context.vfp.__fpcr);
258   }
259 #else
260   // Read the registers from our thread
261   mach_msg_type_number_t count = ARM_VFP_STATE_COUNT;
262   kret = ::thread_get_state(m_thread->MachPortNumber(), ARM_VFP_STATE,
263                             (thread_state_t)&m_state.context.vfp, &count);
264 
265   if (DNBLogEnabledForAny(LOG_THREAD)) {
266     uint32_t *r = &m_state.context.vfp.__r[0];
267     DNBLogThreaded(
268         "thread_get_state(0x%4.4x, %u, &gpr, %u) => 0x%8.8x (count => %u)",
269         m_thread->MachPortNumber(), ARM_THREAD_STATE, ARM_THREAD_STATE_COUNT,
270         kret, count);
271     DNBLogThreaded("   s0=%8.8x  s1=%8.8x  s2=%8.8x  s3=%8.8x  s4=%8.8x  "
272                    "s5=%8.8x  s6=%8.8x  s7=%8.8x",
273                    r[0], r[1], r[2], r[3], r[4], r[5], r[6], r[7]);
274     DNBLogThreaded("   s8=%8.8x  s9=%8.8x s10=%8.8x s11=%8.8x s12=%8.8x "
275                    "s13=%8.8x s14=%8.8x s15=%8.8x",
276                    r[8], r[9], r[10], r[11], r[12], r[13], r[14], r[15]);
277     DNBLogThreaded("  s16=%8.8x s17=%8.8x s18=%8.8x s19=%8.8x s20=%8.8x "
278                    "s21=%8.8x s22=%8.8x s23=%8.8x",
279                    r[16], r[17], r[18], r[19], r[20], r[21], r[22], r[23]);
280     DNBLogThreaded("  s24=%8.8x s25=%8.8x s26=%8.8x s27=%8.8x s28=%8.8x "
281                    "s29=%8.8x s30=%8.8x s31=%8.8x",
282                    r[24], r[25], r[26], r[27], r[28], r[29], r[30], r[31]);
283     DNBLogThreaded("  s32=%8.8x s33=%8.8x s34=%8.8x s35=%8.8x s36=%8.8x "
284                    "s37=%8.8x s38=%8.8x s39=%8.8x",
285                    r[32], r[33], r[34], r[35], r[36], r[37], r[38], r[39]);
286     DNBLogThreaded("  s40=%8.8x s41=%8.8x s42=%8.8x s43=%8.8x s44=%8.8x "
287                    "s45=%8.8x s46=%8.8x s47=%8.8x",
288                    r[40], r[41], r[42], r[43], r[44], r[45], r[46], r[47]);
289     DNBLogThreaded("  s48=%8.8x s49=%8.8x s50=%8.8x s51=%8.8x s52=%8.8x "
290                    "s53=%8.8x s54=%8.8x s55=%8.8x",
291                    r[48], r[49], r[50], r[51], r[52], r[53], r[54], r[55]);
292     DNBLogThreaded("  s56=%8.8x s57=%8.8x s58=%8.8x s59=%8.8x s60=%8.8x "
293                    "s61=%8.8x s62=%8.8x s63=%8.8x fpscr=%8.8x",
294                    r[56], r[57], r[58], r[59], r[60], r[61], r[62], r[63],
295                    r[64]);
296   }
297 
298 #endif
299   m_state.SetError(set, Read, kret);
300   return kret;
301 }
302 
GetEXCState(bool force)303 kern_return_t DNBArchMachARM::GetEXCState(bool force) {
304   int set = e_regSetEXC;
305   // Check if we have valid cached registers
306   if (!force && m_state.GetError(set, Read) == KERN_SUCCESS)
307     return KERN_SUCCESS;
308 
309   // Read the registers from our thread
310   mach_msg_type_number_t count = ARM_EXCEPTION_STATE_COUNT;
311   kern_return_t kret =
312       ::thread_get_state(m_thread->MachPortNumber(), ARM_EXCEPTION_STATE,
313                          (thread_state_t)&m_state.context.exc, &count);
314   m_state.SetError(set, Read, kret);
315   return kret;
316 }
317 
DumpDBGState(const DNBArchMachARM::DBG & dbg)318 static void DumpDBGState(const DNBArchMachARM::DBG &dbg) {
319   uint32_t i = 0;
320   for (i = 0; i < 16; i++) {
321     DNBLogThreadedIf(LOG_STEP, "BVR%-2u/BCR%-2u = { 0x%8.8x, 0x%8.8x } "
322                                "WVR%-2u/WCR%-2u = { 0x%8.8x, 0x%8.8x }",
323                      i, i, dbg.__bvr[i], dbg.__bcr[i], i, i, dbg.__wvr[i],
324                      dbg.__wcr[i]);
325   }
326 }
327 
GetDBGState(bool force)328 kern_return_t DNBArchMachARM::GetDBGState(bool force) {
329   int set = e_regSetDBG;
330 
331   // Check if we have valid cached registers
332   if (!force && m_state.GetError(set, Read) == KERN_SUCCESS)
333     return KERN_SUCCESS;
334 
335 // Read the registers from our thread
336 #if defined(ARM_DEBUG_STATE32) && (defined(__arm64__) || defined(__aarch64__))
337   mach_msg_type_number_t count = ARM_DEBUG_STATE32_COUNT;
338   kern_return_t kret =
339       ::thread_get_state(m_thread->MachPortNumber(), ARM_DEBUG_STATE32,
340                          (thread_state_t)&m_state.dbg, &count);
341 #else
342   mach_msg_type_number_t count = ARM_DEBUG_STATE_COUNT;
343   kern_return_t kret =
344       ::thread_get_state(m_thread->MachPortNumber(), ARM_DEBUG_STATE,
345                          (thread_state_t)&m_state.dbg, &count);
346 #endif
347   m_state.SetError(set, Read, kret);
348 
349   return kret;
350 }
351 
SetGPRState()352 kern_return_t DNBArchMachARM::SetGPRState() {
353   int set = e_regSetGPR;
354   kern_return_t kret = ::thread_set_state(
355       m_thread->MachPortNumber(), ARM_THREAD_STATE,
356       (thread_state_t)&m_state.context.gpr, ARM_THREAD_STATE_COUNT);
357   m_state.SetError(set, Write,
358                    kret); // Set the current write error for this register set
359   m_state.InvalidateRegisterSetState(set); // Invalidate the current register
360                                            // state in case registers are read
361                                            // back differently
362   return kret;                             // Return the error code
363 }
364 
SetVFPState()365 kern_return_t DNBArchMachARM::SetVFPState() {
366   int set = e_regSetVFP;
367   kern_return_t kret;
368   mach_msg_type_number_t count;
369 
370 #if defined(__arm64__) || defined(__aarch64__)
371   count = ARM_NEON_STATE_COUNT;
372   kret = ::thread_set_state(m_thread->MachPortNumber(), ARM_NEON_STATE,
373                             (thread_state_t)&m_state.context.vfp, count);
374 #else
375   count = ARM_VFP_STATE_COUNT;
376   kret = ::thread_set_state(m_thread->MachPortNumber(), ARM_VFP_STATE,
377                             (thread_state_t)&m_state.context.vfp, count);
378 #endif
379 
380 #if defined(__arm64__) || defined(__aarch64__)
381   if (DNBLogEnabledForAny(LOG_THREAD)) {
382     DNBLogThreaded(
383         "thread_set_state(0x%4.4x, %u, &vfp, %u) => 0x%8.8x (count = %u) regs"
384         "\n   q0  = 0x%16.16llx%16.16llx"
385         "\n   q1  = 0x%16.16llx%16.16llx"
386         "\n   q2  = 0x%16.16llx%16.16llx"
387         "\n   q3  = 0x%16.16llx%16.16llx"
388         "\n   q4  = 0x%16.16llx%16.16llx"
389         "\n   q5  = 0x%16.16llx%16.16llx"
390         "\n   q6  = 0x%16.16llx%16.16llx"
391         "\n   q7  = 0x%16.16llx%16.16llx"
392         "\n   q8  = 0x%16.16llx%16.16llx"
393         "\n   q9  = 0x%16.16llx%16.16llx"
394         "\n   q10 = 0x%16.16llx%16.16llx"
395         "\n   q11 = 0x%16.16llx%16.16llx"
396         "\n   q12 = 0x%16.16llx%16.16llx"
397         "\n   q13 = 0x%16.16llx%16.16llx"
398         "\n   q14 = 0x%16.16llx%16.16llx"
399         "\n   q15 = 0x%16.16llx%16.16llx"
400         "\n  fpsr = 0x%8.8x"
401         "\n  fpcr = 0x%8.8x\n\n",
402         m_thread->MachPortNumber(), ARM_NEON_STATE, ARM_NEON_STATE_COUNT, kret,
403         count, ((uint64_t *)&m_state.context.vfp.__v[0])[0],
404         ((uint64_t *)&m_state.context.vfp.__v[0])[1],
405         ((uint64_t *)&m_state.context.vfp.__v[1])[0],
406         ((uint64_t *)&m_state.context.vfp.__v[1])[1],
407         ((uint64_t *)&m_state.context.vfp.__v[2])[0],
408         ((uint64_t *)&m_state.context.vfp.__v[2])[1],
409         ((uint64_t *)&m_state.context.vfp.__v[3])[0],
410         ((uint64_t *)&m_state.context.vfp.__v[3])[1],
411         ((uint64_t *)&m_state.context.vfp.__v[4])[0],
412         ((uint64_t *)&m_state.context.vfp.__v[4])[1],
413         ((uint64_t *)&m_state.context.vfp.__v[5])[0],
414         ((uint64_t *)&m_state.context.vfp.__v[5])[1],
415         ((uint64_t *)&m_state.context.vfp.__v[6])[0],
416         ((uint64_t *)&m_state.context.vfp.__v[6])[1],
417         ((uint64_t *)&m_state.context.vfp.__v[7])[0],
418         ((uint64_t *)&m_state.context.vfp.__v[7])[1],
419         ((uint64_t *)&m_state.context.vfp.__v[8])[0],
420         ((uint64_t *)&m_state.context.vfp.__v[8])[1],
421         ((uint64_t *)&m_state.context.vfp.__v[9])[0],
422         ((uint64_t *)&m_state.context.vfp.__v[9])[1],
423         ((uint64_t *)&m_state.context.vfp.__v[10])[0],
424         ((uint64_t *)&m_state.context.vfp.__v[10])[1],
425         ((uint64_t *)&m_state.context.vfp.__v[11])[0],
426         ((uint64_t *)&m_state.context.vfp.__v[11])[1],
427         ((uint64_t *)&m_state.context.vfp.__v[12])[0],
428         ((uint64_t *)&m_state.context.vfp.__v[12])[1],
429         ((uint64_t *)&m_state.context.vfp.__v[13])[0],
430         ((uint64_t *)&m_state.context.vfp.__v[13])[1],
431         ((uint64_t *)&m_state.context.vfp.__v[14])[0],
432         ((uint64_t *)&m_state.context.vfp.__v[14])[1],
433         ((uint64_t *)&m_state.context.vfp.__v[15])[0],
434         ((uint64_t *)&m_state.context.vfp.__v[15])[1],
435         m_state.context.vfp.__fpsr, m_state.context.vfp.__fpcr);
436   }
437 #else
438   if (DNBLogEnabledForAny(LOG_THREAD)) {
439     uint32_t *r = &m_state.context.vfp.__r[0];
440     DNBLogThreaded(
441         "thread_get_state(0x%4.4x, %u, &gpr, %u) => 0x%8.8x (count => %u)",
442         m_thread->MachPortNumber(), ARM_THREAD_STATE, ARM_THREAD_STATE_COUNT,
443         kret, count);
444     DNBLogThreaded("   s0=%8.8x  s1=%8.8x  s2=%8.8x  s3=%8.8x  s4=%8.8x  "
445                    "s5=%8.8x  s6=%8.8x  s7=%8.8x",
446                    r[0], r[1], r[2], r[3], r[4], r[5], r[6], r[7]);
447     DNBLogThreaded("   s8=%8.8x  s9=%8.8x s10=%8.8x s11=%8.8x s12=%8.8x "
448                    "s13=%8.8x s14=%8.8x s15=%8.8x",
449                    r[8], r[9], r[10], r[11], r[12], r[13], r[14], r[15]);
450     DNBLogThreaded("  s16=%8.8x s17=%8.8x s18=%8.8x s19=%8.8x s20=%8.8x "
451                    "s21=%8.8x s22=%8.8x s23=%8.8x",
452                    r[16], r[17], r[18], r[19], r[20], r[21], r[22], r[23]);
453     DNBLogThreaded("  s24=%8.8x s25=%8.8x s26=%8.8x s27=%8.8x s28=%8.8x "
454                    "s29=%8.8x s30=%8.8x s31=%8.8x",
455                    r[24], r[25], r[26], r[27], r[28], r[29], r[30], r[31]);
456     DNBLogThreaded("  s32=%8.8x s33=%8.8x s34=%8.8x s35=%8.8x s36=%8.8x "
457                    "s37=%8.8x s38=%8.8x s39=%8.8x",
458                    r[32], r[33], r[34], r[35], r[36], r[37], r[38], r[39]);
459     DNBLogThreaded("  s40=%8.8x s41=%8.8x s42=%8.8x s43=%8.8x s44=%8.8x "
460                    "s45=%8.8x s46=%8.8x s47=%8.8x",
461                    r[40], r[41], r[42], r[43], r[44], r[45], r[46], r[47]);
462     DNBLogThreaded("  s48=%8.8x s49=%8.8x s50=%8.8x s51=%8.8x s52=%8.8x "
463                    "s53=%8.8x s54=%8.8x s55=%8.8x",
464                    r[48], r[49], r[50], r[51], r[52], r[53], r[54], r[55]);
465     DNBLogThreaded("  s56=%8.8x s57=%8.8x s58=%8.8x s59=%8.8x s60=%8.8x "
466                    "s61=%8.8x s62=%8.8x s63=%8.8x fpscr=%8.8x",
467                    r[56], r[57], r[58], r[59], r[60], r[61], r[62], r[63],
468                    r[64]);
469   }
470 #endif
471 
472   m_state.SetError(set, Write,
473                    kret); // Set the current write error for this register set
474   m_state.InvalidateRegisterSetState(set); // Invalidate the current register
475                                            // state in case registers are read
476                                            // back differently
477   return kret;                             // Return the error code
478 }
479 
SetEXCState()480 kern_return_t DNBArchMachARM::SetEXCState() {
481   int set = e_regSetEXC;
482   kern_return_t kret = ::thread_set_state(
483       m_thread->MachPortNumber(), ARM_EXCEPTION_STATE,
484       (thread_state_t)&m_state.context.exc, ARM_EXCEPTION_STATE_COUNT);
485   m_state.SetError(set, Write,
486                    kret); // Set the current write error for this register set
487   m_state.InvalidateRegisterSetState(set); // Invalidate the current register
488                                            // state in case registers are read
489                                            // back differently
490   return kret;                             // Return the error code
491 }
492 
SetDBGState(bool also_set_on_task)493 kern_return_t DNBArchMachARM::SetDBGState(bool also_set_on_task) {
494   int set = e_regSetDBG;
495 #if defined(ARM_DEBUG_STATE32) && (defined(__arm64__) || defined(__aarch64__))
496   kern_return_t kret =
497       ::thread_set_state(m_thread->MachPortNumber(), ARM_DEBUG_STATE32,
498                          (thread_state_t)&m_state.dbg, ARM_DEBUG_STATE32_COUNT);
499   if (also_set_on_task) {
500     kern_return_t task_kret = ::task_set_state(
501         m_thread->Process()->Task().TaskPort(), ARM_DEBUG_STATE32,
502         (thread_state_t)&m_state.dbg, ARM_DEBUG_STATE32_COUNT);
503     if (task_kret != KERN_SUCCESS)
504       DNBLogThreadedIf(LOG_WATCHPOINTS, "DNBArchMachARM::SetDBGState failed to "
505                                         "set debug control register state: "
506                                         "0x%8.8x.",
507                        kret);
508   }
509 #else
510   kern_return_t kret =
511       ::thread_set_state(m_thread->MachPortNumber(), ARM_DEBUG_STATE,
512                          (thread_state_t)&m_state.dbg, ARM_DEBUG_STATE_COUNT);
513   if (also_set_on_task) {
514     kern_return_t task_kret = ::task_set_state(
515         m_thread->Process()->Task().TaskPort(), ARM_DEBUG_STATE,
516         (thread_state_t)&m_state.dbg, ARM_DEBUG_STATE_COUNT);
517     if (task_kret != KERN_SUCCESS)
518       DNBLogThreadedIf(LOG_WATCHPOINTS, "DNBArchMachARM::SetDBGState failed to "
519                                         "set debug control register state: "
520                                         "0x%8.8x.",
521                        kret);
522   }
523 #endif
524 
525   m_state.SetError(set, Write,
526                    kret); // Set the current write error for this register set
527   m_state.InvalidateRegisterSetState(set); // Invalidate the current register
528                                            // state in case registers are read
529                                            // back differently
530   return kret;                             // Return the error code
531 }
532 
ThreadWillResume()533 void DNBArchMachARM::ThreadWillResume() {
534   // Do we need to step this thread? If so, let the mach thread tell us so.
535   if (m_thread->IsStepping()) {
536     // This is the primary thread, let the arch do anything it needs
537     if (NumSupportedHardwareBreakpoints() > 0) {
538       if (EnableHardwareSingleStep(true) != KERN_SUCCESS) {
539         DNBLogThreaded("DNBArchMachARM::ThreadWillResume() failed to enable "
540                        "hardware single step");
541       }
542     }
543   }
544 
545   // Disable the triggered watchpoint temporarily before we resume.
546   // Plus, we try to enable hardware single step to execute past the instruction
547   // which triggered our watchpoint.
548   if (m_watchpoint_did_occur) {
549     if (m_watchpoint_hw_index >= 0) {
550       kern_return_t kret = GetDBGState(false);
551       if (kret == KERN_SUCCESS &&
552           !IsWatchpointEnabled(m_state.dbg, m_watchpoint_hw_index)) {
553         // The watchpoint might have been disabled by the user.  We don't need
554         // to do anything at all
555         // to enable hardware single stepping.
556         m_watchpoint_did_occur = false;
557         m_watchpoint_hw_index = -1;
558         return;
559       }
560 
561       DisableHardwareWatchpoint(m_watchpoint_hw_index, false);
562       DNBLogThreadedIf(LOG_WATCHPOINTS, "DNBArchMachARM::ThreadWillResume() "
563                                         "DisableHardwareWatchpoint(%d) called",
564                        m_watchpoint_hw_index);
565 
566       // Enable hardware single step to move past the watchpoint-triggering
567       // instruction.
568       m_watchpoint_resume_single_step_enabled =
569           (EnableHardwareSingleStep(true) == KERN_SUCCESS);
570 
571       // If we are not able to enable single step to move past the
572       // watchpoint-triggering instruction,
573       // at least we should reset the two watchpoint member variables so that
574       // the next time around
575       // this callback function is invoked, the enclosing logical branch is
576       // skipped.
577       if (!m_watchpoint_resume_single_step_enabled) {
578         // Reset the two watchpoint member variables.
579         m_watchpoint_did_occur = false;
580         m_watchpoint_hw_index = -1;
581         DNBLogThreadedIf(
582             LOG_WATCHPOINTS,
583             "DNBArchMachARM::ThreadWillResume() failed to enable single step");
584       } else
585         DNBLogThreadedIf(LOG_WATCHPOINTS, "DNBArchMachARM::ThreadWillResume() "
586                                           "succeeded to enable single step");
587     }
588   }
589 }
590 
ThreadDidStop()591 bool DNBArchMachARM::ThreadDidStop() {
592   bool success = true;
593 
594   m_state.InvalidateRegisterSetState(e_regSetALL);
595 
596   if (m_watchpoint_resume_single_step_enabled) {
597     // Great!  We now disable the hardware single step as well as re-enable the
598     // hardware watchpoint.
599     // See also ThreadWillResume().
600     if (EnableHardwareSingleStep(false) == KERN_SUCCESS) {
601       if (m_watchpoint_did_occur && m_watchpoint_hw_index >= 0) {
602         ReenableHardwareWatchpoint(m_watchpoint_hw_index);
603         m_watchpoint_resume_single_step_enabled = false;
604         m_watchpoint_did_occur = false;
605         m_watchpoint_hw_index = -1;
606       } else {
607         DNBLogError("internal error detected: m_watchpoint_resume_step_enabled "
608                     "is true but (m_watchpoint_did_occur && "
609                     "m_watchpoint_hw_index >= 0) does not hold!");
610       }
611     } else {
612       DNBLogError("internal error detected: m_watchpoint_resume_step_enabled "
613                   "is true but unable to disable single step!");
614     }
615   }
616 
617   // Are we stepping a single instruction?
618   if (GetGPRState(true) == KERN_SUCCESS) {
619     // We are single stepping, was this the primary thread?
620     if (m_thread->IsStepping()) {
621       success = EnableHardwareSingleStep(false) == KERN_SUCCESS;
622     } else {
623       // The MachThread will automatically restore the suspend count
624       // in ThreadDidStop(), so we don't need to do anything here if
625       // we weren't the primary thread the last time
626     }
627   }
628   return success;
629 }
630 
NotifyException(MachException::Data & exc)631 bool DNBArchMachARM::NotifyException(MachException::Data &exc) {
632   switch (exc.exc_type) {
633   default:
634     break;
635   case EXC_BREAKPOINT:
636     if (exc.exc_data.size() == 2 && exc.exc_data[0] == EXC_ARM_DA_DEBUG) {
637       // The data break address is passed as exc_data[1].
638       nub_addr_t addr = exc.exc_data[1];
639       // Find the hardware index with the side effect of possibly massaging the
640       // addr to return the starting address as seen from the debugger side.
641       uint32_t hw_index = GetHardwareWatchpointHit(addr);
642       DNBLogThreadedIf(LOG_WATCHPOINTS, "DNBArchMachARM::NotifyException "
643                                         "watchpoint %d was hit on address "
644                                         "0x%llx",
645                        hw_index, (uint64_t)addr);
646       const int num_watchpoints = NumSupportedHardwareWatchpoints();
647       for (int i = 0; i < num_watchpoints; i++) {
648         if (LoHi[i] != 0 && LoHi[i] == hw_index && LoHi[i] != i &&
649             GetWatchpointAddressByIndex(i) != INVALID_NUB_ADDRESS) {
650           addr = GetWatchpointAddressByIndex(i);
651           DNBLogThreadedIf(LOG_WATCHPOINTS, "DNBArchMachARM::NotifyException "
652                                             "It is a linked watchpoint; "
653                                             "rewritten to index %d addr 0x%llx",
654                            LoHi[i], (uint64_t)addr);
655         }
656       }
657       if (hw_index != INVALID_NUB_HW_INDEX) {
658         m_watchpoint_did_occur = true;
659         m_watchpoint_hw_index = hw_index;
660         exc.exc_data[1] = addr;
661         // Piggyback the hw_index in the exc.data.
662         exc.exc_data.push_back(hw_index);
663       }
664 
665       return true;
666     }
667     break;
668   }
669   return false;
670 }
671 
StepNotComplete()672 bool DNBArchMachARM::StepNotComplete() {
673   if (m_hw_single_chained_step_addr != INVALID_NUB_ADDRESS) {
674     kern_return_t kret = KERN_INVALID_ARGUMENT;
675     kret = GetGPRState(false);
676     if (kret == KERN_SUCCESS) {
677       if (m_state.context.gpr.__pc == m_hw_single_chained_step_addr) {
678         DNBLogThreadedIf(LOG_STEP, "Need to step some more at 0x%8.8llx",
679                          (uint64_t)m_hw_single_chained_step_addr);
680         return true;
681       }
682     }
683   }
684 
685   m_hw_single_chained_step_addr = INVALID_NUB_ADDRESS;
686   return false;
687 }
688 
689 // Set the single step bit in the processor status register.
EnableHardwareSingleStep(bool enable)690 kern_return_t DNBArchMachARM::EnableHardwareSingleStep(bool enable) {
691   DNBError err;
692   DNBLogThreadedIf(LOG_STEP, "%s( enable = %d )", __FUNCTION__, enable);
693 
694   err = GetGPRState(false);
695 
696   if (err.Fail()) {
697     err.LogThreaded("%s: failed to read the GPR registers", __FUNCTION__);
698     return err.Status();
699   }
700 
701   err = GetDBGState(false);
702 
703   if (err.Fail()) {
704     err.LogThreaded("%s: failed to read the DBG registers", __FUNCTION__);
705     return err.Status();
706   }
707 
708 // The use of __arm64__ here is not ideal.  If debugserver is running on
709 // an armv8 device, regardless of whether it was built for arch arm or arch
710 // arm64,
711 // it needs to use the MDSCR_EL1 SS bit to single instruction step.
712 
713 #if defined(__arm64__) || defined(__aarch64__)
714   if (enable) {
715     DNBLogThreadedIf(LOG_STEP,
716                      "%s: Setting MDSCR_EL1 Single Step bit at pc 0x%llx",
717                      __FUNCTION__, (uint64_t)m_state.context.gpr.__pc);
718     m_state.dbg.__mdscr_el1 |=
719         1; // Set bit 0 (single step, SS) in the MDSCR_EL1.
720   } else {
721     DNBLogThreadedIf(LOG_STEP,
722                      "%s: Clearing MDSCR_EL1 Single Step bit at pc 0x%llx",
723                      __FUNCTION__, (uint64_t)m_state.context.gpr.__pc);
724     m_state.dbg.__mdscr_el1 &=
725         ~(1ULL); // Clear bit 0 (single step, SS) in the MDSCR_EL1.
726   }
727 #else
728   const uint32_t i = 0;
729   if (enable) {
730     m_hw_single_chained_step_addr = INVALID_NUB_ADDRESS;
731 
732     // Save our previous state
733     m_dbg_save = m_state.dbg;
734     // Set a breakpoint that will stop when the PC doesn't match the current
735     // one!
736     m_state.dbg.__bvr[i] =
737         m_state.context.gpr.__pc &
738         0xFFFFFFFCu; // Set the current PC as the breakpoint address
739     m_state.dbg.__bcr[i] = BCR_M_IMVA_MISMATCH | // Stop on address mismatch
740                            S_USER |              // Stop only in user mode
741                            BCR_ENABLE;           // Enable this breakpoint
742     if (m_state.context.gpr.__cpsr & 0x20) {
743       // Thumb breakpoint
744       if (m_state.context.gpr.__pc & 2)
745         m_state.dbg.__bcr[i] |= BAS_IMVA_2_3;
746       else
747         m_state.dbg.__bcr[i] |= BAS_IMVA_0_1;
748 
749       uint16_t opcode;
750       if (sizeof(opcode) ==
751           m_thread->Process()->Task().ReadMemory(m_state.context.gpr.__pc,
752                                                  sizeof(opcode), &opcode)) {
753         if (IsThumb32Opcode(opcode)) {
754           // 32 bit thumb opcode...
755           if (m_state.context.gpr.__pc & 2) {
756             // We can't take care of a 32 bit thumb instruction single step
757             // with just IVA mismatching. We will need to chain an extra
758             // hardware single step in order to complete this single step...
759             m_hw_single_chained_step_addr = m_state.context.gpr.__pc + 2;
760           } else {
761             // Extend the number of bits to ignore for the mismatch
762             m_state.dbg.__bcr[i] |= BAS_IMVA_ALL;
763           }
764         }
765       }
766     } else {
767       // ARM breakpoint
768       m_state.dbg.__bcr[i] |= BAS_IMVA_ALL; // Stop when any address bits change
769     }
770 
771     DNBLogThreadedIf(LOG_STEP, "%s: BVR%u=0x%8.8x  BCR%u=0x%8.8x", __FUNCTION__,
772                      i, m_state.dbg.__bvr[i], i, m_state.dbg.__bcr[i]);
773 
774     for (uint32_t j = i + 1; j < 16; ++j) {
775       // Disable all others
776       m_state.dbg.__bvr[j] = 0;
777       m_state.dbg.__bcr[j] = 0;
778     }
779   } else {
780     // Just restore the state we had before we did single stepping
781     m_state.dbg = m_dbg_save;
782   }
783 #endif
784 
785   return SetDBGState(false);
786 }
787 
788 // return 1 if bit "BIT" is set in "value"
bit(uint32_t value,uint32_t bit)789 static inline uint32_t bit(uint32_t value, uint32_t bit) {
790   return (value >> bit) & 1u;
791 }
792 
793 // return the bitfield "value[msbit:lsbit]".
bits(uint32_t value,uint32_t msbit,uint32_t lsbit)794 static inline uint32_t bits(uint32_t value, uint32_t msbit, uint32_t lsbit) {
795   assert(msbit >= lsbit);
796   uint32_t shift_left = sizeof(value) * 8 - 1 - msbit;
797   value <<=
798       shift_left; // shift anything above the msbit off of the unsigned edge
799   value >>= (shift_left + lsbit); // shift it back again down to the lsbit
800                                   // (including undoing any shift from above)
801   return value;                   // return our result
802 }
803 
ConditionPassed(uint8_t condition,uint32_t cpsr)804 bool DNBArchMachARM::ConditionPassed(uint8_t condition, uint32_t cpsr) {
805   uint32_t cpsr_n = bit(cpsr, 31); // Negative condition code flag
806   uint32_t cpsr_z = bit(cpsr, 30); // Zero condition code flag
807   uint32_t cpsr_c = bit(cpsr, 29); // Carry condition code flag
808   uint32_t cpsr_v = bit(cpsr, 28); // Overflow condition code flag
809 
810   switch (condition) {
811   case COND_EQ: // (0x0)
812     if (cpsr_z == 1)
813       return true;
814     break;
815   case COND_NE: // (0x1)
816     if (cpsr_z == 0)
817       return true;
818     break;
819   case COND_CS: // (0x2)
820     if (cpsr_c == 1)
821       return true;
822     break;
823   case COND_CC: // (0x3)
824     if (cpsr_c == 0)
825       return true;
826     break;
827   case COND_MI: // (0x4)
828     if (cpsr_n == 1)
829       return true;
830     break;
831   case COND_PL: // (0x5)
832     if (cpsr_n == 0)
833       return true;
834     break;
835   case COND_VS: // (0x6)
836     if (cpsr_v == 1)
837       return true;
838     break;
839   case COND_VC: // (0x7)
840     if (cpsr_v == 0)
841       return true;
842     break;
843   case COND_HI: // (0x8)
844     if ((cpsr_c == 1) && (cpsr_z == 0))
845       return true;
846     break;
847   case COND_LS: // (0x9)
848     if ((cpsr_c == 0) || (cpsr_z == 1))
849       return true;
850     break;
851   case COND_GE: // (0xA)
852     if (cpsr_n == cpsr_v)
853       return true;
854     break;
855   case COND_LT: // (0xB)
856     if (cpsr_n != cpsr_v)
857       return true;
858     break;
859   case COND_GT: // (0xC)
860     if ((cpsr_z == 0) && (cpsr_n == cpsr_v))
861       return true;
862     break;
863   case COND_LE: // (0xD)
864     if ((cpsr_z == 1) || (cpsr_n != cpsr_v))
865       return true;
866     break;
867   default:
868     return true;
869     break;
870   }
871 
872   return false;
873 }
874 
NumSupportedHardwareBreakpoints()875 uint32_t DNBArchMachARM::NumSupportedHardwareBreakpoints() {
876   // Set the init value to something that will let us know that we need to
877   // autodetect how many breakpoints are supported dynamically...
878   static uint32_t g_num_supported_hw_breakpoints = UINT_MAX;
879   if (g_num_supported_hw_breakpoints == UINT_MAX) {
880     // Set this to zero in case we can't tell if there are any HW breakpoints
881     g_num_supported_hw_breakpoints = 0;
882 
883     size_t len;
884     uint32_t n = 0;
885     len = sizeof(n);
886     if (::sysctlbyname("hw.optional.breakpoint", &n, &len, NULL, 0) == 0) {
887       g_num_supported_hw_breakpoints = n;
888       DNBLogThreadedIf(LOG_THREAD, "hw.optional.breakpoint=%u", n);
889     } else {
890 #if !defined(__arm64__) && !defined(__aarch64__)
891       // Read the DBGDIDR to get the number of available hardware breakpoints
892       // However, in some of our current armv7 processors, hardware
893       // breakpoints/watchpoints were not properly connected. So detect those
894       // cases using a field in a sysctl. For now we are using "hw.cpusubtype"
895       // field to distinguish CPU architectures. This is a hack until we can
896       // get <rdar://problem/6372672> fixed, at which point we will switch to
897       // using a different sysctl string that will tell us how many BRPs
898       // are available to us directly without having to read DBGDIDR.
899       uint32_t register_DBGDIDR;
900 
901       asm("mrc p14, 0, %0, c0, c0, 0" : "=r"(register_DBGDIDR));
902       uint32_t numBRPs = bits(register_DBGDIDR, 27, 24);
903       // Zero is reserved for the BRP count, so don't increment it if it is zero
904       if (numBRPs > 0)
905         numBRPs++;
906       DNBLogThreadedIf(LOG_THREAD, "DBGDIDR=0x%8.8x (number BRP pairs = %u)",
907                        register_DBGDIDR, numBRPs);
908 
909       if (numBRPs > 0) {
910         uint32_t cpusubtype;
911         len = sizeof(cpusubtype);
912         // TODO: remove this hack and change to using hw.optional.xx when
913         // implmented
914         if (::sysctlbyname("hw.cpusubtype", &cpusubtype, &len, NULL, 0) == 0) {
915           DNBLogThreadedIf(LOG_THREAD, "hw.cpusubtype=%d", cpusubtype);
916           if (cpusubtype == CPU_SUBTYPE_ARM_V7)
917             DNBLogThreadedIf(LOG_THREAD, "Hardware breakpoints disabled for "
918                                          "armv7 (rdar://problem/6372672)");
919           else
920             g_num_supported_hw_breakpoints = numBRPs;
921         }
922       }
923 #endif
924     }
925   }
926   return g_num_supported_hw_breakpoints;
927 }
928 
NumSupportedHardwareWatchpoints()929 uint32_t DNBArchMachARM::NumSupportedHardwareWatchpoints() {
930   // Set the init value to something that will let us know that we need to
931   // autodetect how many watchpoints are supported dynamically...
932   static uint32_t g_num_supported_hw_watchpoints = UINT_MAX;
933   if (g_num_supported_hw_watchpoints == UINT_MAX) {
934     // Set this to zero in case we can't tell if there are any HW breakpoints
935     g_num_supported_hw_watchpoints = 0;
936 
937     size_t len;
938     uint32_t n = 0;
939     len = sizeof(n);
940     if (::sysctlbyname("hw.optional.watchpoint", &n, &len, NULL, 0) == 0) {
941       g_num_supported_hw_watchpoints = n;
942       DNBLogThreadedIf(LOG_THREAD, "hw.optional.watchpoint=%u", n);
943     } else {
944 #if !defined(__arm64__) && !defined(__aarch64__)
945       // Read the DBGDIDR to get the number of available hardware breakpoints
946       // However, in some of our current armv7 processors, hardware
947       // breakpoints/watchpoints were not properly connected. So detect those
948       // cases using a field in a sysctl. For now we are using "hw.cpusubtype"
949       // field to distinguish CPU architectures. This is a hack until we can
950       // get <rdar://problem/6372672> fixed, at which point we will switch to
951       // using a different sysctl string that will tell us how many WRPs
952       // are available to us directly without having to read DBGDIDR.
953 
954       uint32_t register_DBGDIDR;
955       asm("mrc p14, 0, %0, c0, c0, 0" : "=r"(register_DBGDIDR));
956       uint32_t numWRPs = bits(register_DBGDIDR, 31, 28) + 1;
957       DNBLogThreadedIf(LOG_THREAD, "DBGDIDR=0x%8.8x (number WRP pairs = %u)",
958                        register_DBGDIDR, numWRPs);
959 
960       if (numWRPs > 0) {
961         uint32_t cpusubtype;
962         size_t len;
963         len = sizeof(cpusubtype);
964         // TODO: remove this hack and change to using hw.optional.xx when
965         // implmented
966         if (::sysctlbyname("hw.cpusubtype", &cpusubtype, &len, NULL, 0) == 0) {
967           DNBLogThreadedIf(LOG_THREAD, "hw.cpusubtype=0x%d", cpusubtype);
968 
969           if (cpusubtype == CPU_SUBTYPE_ARM_V7)
970             DNBLogThreadedIf(LOG_THREAD, "Hardware watchpoints disabled for "
971                                          "armv7 (rdar://problem/6372672)");
972           else
973             g_num_supported_hw_watchpoints = numWRPs;
974         }
975       }
976 #endif
977     }
978   }
979   return g_num_supported_hw_watchpoints;
980 }
981 
EnableHardwareBreakpoint(nub_addr_t addr,nub_size_t size,bool also_set_on_task)982 uint32_t DNBArchMachARM::EnableHardwareBreakpoint(nub_addr_t addr,
983                                                   nub_size_t size,
984                                                   bool also_set_on_task) {
985   // Make sure our address isn't bogus
986   if (addr & 1)
987     return INVALID_NUB_HW_INDEX;
988 
989   kern_return_t kret = GetDBGState(false);
990 
991   if (kret == KERN_SUCCESS) {
992     const uint32_t num_hw_breakpoints = NumSupportedHardwareBreakpoints();
993     uint32_t i;
994     for (i = 0; i < num_hw_breakpoints; ++i) {
995       if ((m_state.dbg.__bcr[i] & BCR_ENABLE) == 0)
996         break; // We found an available hw breakpoint slot (in i)
997     }
998 
999     // See if we found an available hw breakpoint slot above
1000     if (i < num_hw_breakpoints) {
1001       // Make sure bits 1:0 are clear in our address
1002       m_state.dbg.__bvr[i] = addr & ~((nub_addr_t)3);
1003 
1004       if (size == 2 || addr & 2) {
1005         uint32_t byte_addr_select = (addr & 2) ? BAS_IMVA_2_3 : BAS_IMVA_0_1;
1006 
1007         // We have a thumb breakpoint
1008         // We have an ARM breakpoint
1009         m_state.dbg.__bcr[i] =
1010             BCR_M_IMVA_MATCH | // Stop on address mismatch
1011             byte_addr_select | // Set the correct byte address select so we only
1012                                // trigger on the correct opcode
1013             S_USER |           // Which modes should this breakpoint stop in?
1014             BCR_ENABLE;        // Enable this hardware breakpoint
1015         DNBLogThreadedIf(LOG_BREAKPOINTS,
1016                          "DNBArchMachARM::EnableHardwareBreakpoint( addr = "
1017                          "0x%8.8llx, size = %llu ) - BVR%u/BCR%u = 0x%8.8x / "
1018                          "0x%8.8x (Thumb)",
1019                          (uint64_t)addr, (uint64_t)size, i, i,
1020                          m_state.dbg.__bvr[i], m_state.dbg.__bcr[i]);
1021       } else if (size == 4) {
1022         // We have an ARM breakpoint
1023         m_state.dbg.__bcr[i] =
1024             BCR_M_IMVA_MATCH | // Stop on address mismatch
1025             BAS_IMVA_ALL | // Stop on any of the four bytes following the IMVA
1026             S_USER |       // Which modes should this breakpoint stop in?
1027             BCR_ENABLE;    // Enable this hardware breakpoint
1028         DNBLogThreadedIf(LOG_BREAKPOINTS,
1029                          "DNBArchMachARM::EnableHardwareBreakpoint( addr = "
1030                          "0x%8.8llx, size = %llu ) - BVR%u/BCR%u = 0x%8.8x / "
1031                          "0x%8.8x (ARM)",
1032                          (uint64_t)addr, (uint64_t)size, i, i,
1033                          m_state.dbg.__bvr[i], m_state.dbg.__bcr[i]);
1034       }
1035 
1036       kret = SetDBGState(false);
1037       DNBLogThreadedIf(LOG_BREAKPOINTS, "DNBArchMachARM::"
1038                                         "EnableHardwareBreakpoint() "
1039                                         "SetDBGState() => 0x%8.8x.",
1040                        kret);
1041 
1042       if (kret == KERN_SUCCESS)
1043         return i;
1044     } else {
1045       DNBLogThreadedIf(LOG_BREAKPOINTS,
1046                        "DNBArchMachARM::EnableHardwareBreakpoint(addr = "
1047                        "0x%8.8llx, size = %llu) => all hardware breakpoint "
1048                        "resources are being used.",
1049                        (uint64_t)addr, (uint64_t)size);
1050     }
1051   }
1052 
1053   return INVALID_NUB_HW_INDEX;
1054 }
1055 
DisableHardwareBreakpoint(uint32_t hw_index,bool also_set_on_task)1056 bool DNBArchMachARM::DisableHardwareBreakpoint(uint32_t hw_index,
1057                                                bool also_set_on_task) {
1058   kern_return_t kret = GetDBGState(false);
1059 
1060   const uint32_t num_hw_points = NumSupportedHardwareBreakpoints();
1061   if (kret == KERN_SUCCESS) {
1062     if (hw_index < num_hw_points) {
1063       m_state.dbg.__bcr[hw_index] = 0;
1064       DNBLogThreadedIf(LOG_BREAKPOINTS, "DNBArchMachARM::SetHardwareBreakpoint("
1065                                         " %u ) - BVR%u = 0x%8.8x  BCR%u = "
1066                                         "0x%8.8x",
1067                        hw_index, hw_index, m_state.dbg.__bvr[hw_index],
1068                        hw_index, m_state.dbg.__bcr[hw_index]);
1069 
1070       kret = SetDBGState(false);
1071 
1072       if (kret == KERN_SUCCESS)
1073         return true;
1074     }
1075   }
1076   return false;
1077 }
1078 
1079 // ARM v7 watchpoints may be either word-size or double-word-size.
1080 // It's implementation defined which they can handle.  It looks like on an
1081 // armv8 device, armv7 processes can watch dwords.  But on a genuine armv7
1082 // device I tried, only word watchpoints are supported.
1083 
1084 #if defined(__arm64__) || defined(__aarch64__)
1085 #define WATCHPOINTS_ARE_DWORD 1
1086 #else
1087 #undef WATCHPOINTS_ARE_DWORD
1088 #endif
1089 
EnableHardwareWatchpoint(nub_addr_t addr,nub_size_t size,bool read,bool write,bool also_set_on_task)1090 uint32_t DNBArchMachARM::EnableHardwareWatchpoint(nub_addr_t addr,
1091                                                   nub_size_t size, bool read,
1092                                                   bool write,
1093                                                   bool also_set_on_task) {
1094 
1095   DNBLogThreadedIf(LOG_WATCHPOINTS, "DNBArchMachARM::EnableHardwareWatchpoint("
1096                                     "addr = 0x%8.8llx, size = %zu, read = %u, "
1097                                     "write = %u)",
1098                    (uint64_t)addr, size, read, write);
1099 
1100   const uint32_t num_hw_watchpoints = NumSupportedHardwareWatchpoints();
1101 
1102   // Can't watch zero bytes
1103   if (size == 0)
1104     return INVALID_NUB_HW_INDEX;
1105 
1106   // We must watch for either read or write
1107   if (read == false && write == false)
1108     return INVALID_NUB_HW_INDEX;
1109 
1110   // Otherwise, can't watch more than 8 bytes per WVR/WCR pair
1111   if (size > 8)
1112     return INVALID_NUB_HW_INDEX;
1113 
1114 // Treat arm watchpoints as having an 8-byte alignment requirement.  You can put
1115 // a watchpoint on a 4-byte
1116 // offset address but you can only watch 4 bytes with that watchpoint.
1117 
1118 // arm watchpoints on an 8-byte (double word) aligned addr can watch any bytes
1119 // in that
1120 // 8-byte long region of memory.  They can watch the 1st byte, the 2nd byte, 3rd
1121 // byte, etc, or any
1122 // combination therein by setting the bits in the BAS [12:5] (Byte Address
1123 // Select) field of
1124 // the DBGWCRn_EL1 reg for the watchpoint.
1125 
1126 // If the MASK [28:24] bits in the DBGWCRn_EL1 allow a single watchpoint to
1127 // monitor a larger region
1128 // of memory (16 bytes, 32 bytes, or 2GB) but the Byte Address Select bitfield
1129 // then selects a larger
1130 // range of bytes, instead of individual bytes.  See the ARMv8 Debug
1131 // Architecture manual for details.
1132 // This implementation does not currently use the MASK bits; the largest single
1133 // region watched by a single
1134 // watchpoint right now is 8-bytes.
1135 
1136 #if defined(WATCHPOINTS_ARE_DWORD)
1137   nub_addr_t aligned_wp_address = addr & ~0x7;
1138   uint32_t addr_dword_offset = addr & 0x7;
1139   const int max_watchpoint_size = 8;
1140 #else
1141   nub_addr_t aligned_wp_address = addr & ~0x3;
1142   uint32_t addr_dword_offset = addr & 0x3;
1143   const int max_watchpoint_size = 4;
1144 #endif
1145 
1146   DNBLogThreadedIf(LOG_WATCHPOINTS, "DNBArchMachARM::EnableHardwareWatchpoint "
1147                                     "aligned_wp_address is 0x%llx and "
1148                                     "addr_dword_offset is 0x%x",
1149                    (uint64_t)aligned_wp_address, addr_dword_offset);
1150 
1151   // Do we need to split up this logical watchpoint into two hardware watchpoint
1152   // registers?
1153   // e.g. a watchpoint of length 4 on address 6.  We need do this with
1154   //   one watchpoint on address 0 with bytes 6 & 7 being monitored
1155   //   one watchpoint on address 8 with bytes 0, 1, 2, 3 being monitored
1156 
1157   if (addr_dword_offset + size > max_watchpoint_size) {
1158     DNBLogThreadedIf(LOG_WATCHPOINTS, "DNBArchMachARM::"
1159                                       "EnableHardwareWatchpoint(addr = "
1160                                       "0x%8.8llx, size = %zu) needs two "
1161                                       "hardware watchpoints slots to monitor",
1162                      (uint64_t)addr, size);
1163     int low_watchpoint_size = max_watchpoint_size - addr_dword_offset;
1164     int high_watchpoint_size = addr_dword_offset + size - max_watchpoint_size;
1165 
1166     uint32_t lo = EnableHardwareWatchpoint(addr, low_watchpoint_size, read,
1167                                            write, also_set_on_task);
1168     if (lo == INVALID_NUB_HW_INDEX)
1169       return INVALID_NUB_HW_INDEX;
1170     uint32_t hi = EnableHardwareWatchpoint(
1171         aligned_wp_address + max_watchpoint_size, high_watchpoint_size, read,
1172         write, also_set_on_task);
1173     if (hi == INVALID_NUB_HW_INDEX) {
1174       DisableHardwareWatchpoint(lo, also_set_on_task);
1175       return INVALID_NUB_HW_INDEX;
1176     }
1177     // Tag this lo->hi mapping in our database.
1178     LoHi[lo] = hi;
1179     return lo;
1180   }
1181 
1182   // At this point
1183   //  1 aligned_wp_address is the requested address rounded down to 8-byte
1184   //  alignment
1185   //  2 addr_dword_offset is the offset into that double word (8-byte) region
1186   //  that we are watching
1187   //  3 size is the number of bytes within that 8-byte region that we are
1188   //  watching
1189 
1190   // Set the Byte Address Selects bits DBGWCRn_EL1 bits [12:5] based on the
1191   // above.
1192   // The bit shift and negation operation will give us 0b11 for 2, 0b1111 for 4,
1193   // etc, up to 0b11111111 for 8.
1194   // then we shift those bits left by the offset into this dword that we are
1195   // interested in.
1196   // e.g. if we are watching bytes 4,5,6,7 in a dword we want a BAS of
1197   // 0b11110000.
1198   uint32_t byte_address_select = ((1 << size) - 1) << addr_dword_offset;
1199 
1200   // Read the debug state
1201   kern_return_t kret = GetDBGState(true);
1202 
1203   if (kret == KERN_SUCCESS) {
1204     // Check to make sure we have the needed hardware support
1205     uint32_t i = 0;
1206 
1207     for (i = 0; i < num_hw_watchpoints; ++i) {
1208       if ((m_state.dbg.__wcr[i] & WCR_ENABLE) == 0)
1209         break; // We found an available hw watchpoint slot (in i)
1210     }
1211 
1212     // See if we found an available hw watchpoint slot above
1213     if (i < num_hw_watchpoints) {
1214       // DumpDBGState(m_state.dbg);
1215 
1216       // Clear any previous LoHi joined-watchpoint that may have been in use
1217       LoHi[i] = 0;
1218 
1219       // shift our Byte Address Select bits up to the correct bit range for the
1220       // DBGWCRn_EL1
1221       byte_address_select = byte_address_select << 5;
1222 
1223       // Make sure bits 1:0 are clear in our address
1224       m_state.dbg.__wvr[i] = aligned_wp_address;   // DVA (Data Virtual Address)
1225       m_state.dbg.__wcr[i] = byte_address_select | // Which bytes that follow
1226                                                    // the DVA that we will watch
1227                              S_USER |              // Stop only in user mode
1228                              (read ? WCR_LOAD : 0) |   // Stop on read access?
1229                              (write ? WCR_STORE : 0) | // Stop on write access?
1230                              WCR_ENABLE; // Enable this watchpoint;
1231 
1232       DNBLogThreadedIf(
1233           LOG_WATCHPOINTS, "DNBArchMachARM::EnableHardwareWatchpoint() adding "
1234                            "watchpoint on address 0x%llx with control register "
1235                            "value 0x%x",
1236           (uint64_t)m_state.dbg.__wvr[i], (uint32_t)m_state.dbg.__wcr[i]);
1237 
1238       // The kernel will set the MDE_ENABLE bit in the MDSCR_EL1 for us
1239       // automatically, don't need to do it here.
1240 
1241       kret = SetDBGState(also_set_on_task);
1242       // DumpDBGState(m_state.dbg);
1243 
1244       DNBLogThreadedIf(LOG_WATCHPOINTS, "DNBArchMachARM::"
1245                                         "EnableHardwareWatchpoint() "
1246                                         "SetDBGState() => 0x%8.8x.",
1247                        kret);
1248 
1249       if (kret == KERN_SUCCESS)
1250         return i;
1251     } else {
1252       DNBLogThreadedIf(LOG_WATCHPOINTS, "DNBArchMachARM::"
1253                                         "EnableHardwareWatchpoint(): All "
1254                                         "hardware resources (%u) are in use.",
1255                        num_hw_watchpoints);
1256     }
1257   }
1258   return INVALID_NUB_HW_INDEX;
1259 }
1260 
ReenableHardwareWatchpoint(uint32_t hw_index)1261 bool DNBArchMachARM::ReenableHardwareWatchpoint(uint32_t hw_index) {
1262   // If this logical watchpoint # is actually implemented using
1263   // two hardware watchpoint registers, re-enable both of them.
1264 
1265   if (hw_index < NumSupportedHardwareWatchpoints() && LoHi[hw_index]) {
1266     return ReenableHardwareWatchpoint_helper(hw_index) &&
1267            ReenableHardwareWatchpoint_helper(LoHi[hw_index]);
1268   } else {
1269     return ReenableHardwareWatchpoint_helper(hw_index);
1270   }
1271 }
1272 
ReenableHardwareWatchpoint_helper(uint32_t hw_index)1273 bool DNBArchMachARM::ReenableHardwareWatchpoint_helper(uint32_t hw_index) {
1274   kern_return_t kret = GetDBGState(false);
1275   if (kret != KERN_SUCCESS)
1276     return false;
1277   const uint32_t num_hw_points = NumSupportedHardwareWatchpoints();
1278   if (hw_index >= num_hw_points)
1279     return false;
1280 
1281   m_state.dbg.__wvr[hw_index] = m_disabled_watchpoints[hw_index].addr;
1282   m_state.dbg.__wcr[hw_index] = m_disabled_watchpoints[hw_index].control;
1283 
1284   DNBLogThreadedIf(LOG_WATCHPOINTS, "DNBArchMachARM::EnableHardwareWatchpoint( "
1285                                     "%u ) - WVR%u = 0x%8.8llx  WCR%u = "
1286                                     "0x%8.8llx",
1287                    hw_index, hw_index, (uint64_t)m_state.dbg.__wvr[hw_index],
1288                    hw_index, (uint64_t)m_state.dbg.__wcr[hw_index]);
1289 
1290   // The kernel will set the MDE_ENABLE bit in the MDSCR_EL1 for us
1291   // automatically, don't need to do it here.
1292 
1293   kret = SetDBGState(false);
1294 
1295   return (kret == KERN_SUCCESS);
1296 }
1297 
DisableHardwareWatchpoint(uint32_t hw_index,bool also_set_on_task)1298 bool DNBArchMachARM::DisableHardwareWatchpoint(uint32_t hw_index,
1299                                                bool also_set_on_task) {
1300   if (hw_index < NumSupportedHardwareWatchpoints() && LoHi[hw_index]) {
1301     return DisableHardwareWatchpoint_helper(hw_index, also_set_on_task) &&
1302            DisableHardwareWatchpoint_helper(LoHi[hw_index], also_set_on_task);
1303   } else {
1304     return DisableHardwareWatchpoint_helper(hw_index, also_set_on_task);
1305   }
1306 }
1307 
DisableHardwareWatchpoint_helper(uint32_t hw_index,bool also_set_on_task)1308 bool DNBArchMachARM::DisableHardwareWatchpoint_helper(uint32_t hw_index,
1309                                                       bool also_set_on_task) {
1310   kern_return_t kret = GetDBGState(false);
1311   if (kret != KERN_SUCCESS)
1312     return false;
1313 
1314   const uint32_t num_hw_points = NumSupportedHardwareWatchpoints();
1315   if (hw_index >= num_hw_points)
1316     return false;
1317 
1318   m_disabled_watchpoints[hw_index].addr = m_state.dbg.__wvr[hw_index];
1319   m_disabled_watchpoints[hw_index].control = m_state.dbg.__wcr[hw_index];
1320 
1321   m_state.dbg.__wvr[hw_index] = 0;
1322   m_state.dbg.__wcr[hw_index] = 0;
1323   DNBLogThreadedIf(LOG_WATCHPOINTS, "DNBArchMachARM::DisableHardwareWatchpoint("
1324                                     " %u ) - WVR%u = 0x%8.8llx  WCR%u = "
1325                                     "0x%8.8llx",
1326                    hw_index, hw_index, (uint64_t)m_state.dbg.__wvr[hw_index],
1327                    hw_index, (uint64_t)m_state.dbg.__wcr[hw_index]);
1328 
1329   kret = SetDBGState(also_set_on_task);
1330 
1331   return (kret == KERN_SUCCESS);
1332 }
1333 
1334 // Returns -1 if the trailing bit patterns are not one of:
1335 // { 0b???1, 0b??10, 0b?100, 0b1000 }.
LowestBitSet(uint32_t val)1336 static inline int32_t LowestBitSet(uint32_t val) {
1337   for (unsigned i = 0; i < 4; ++i) {
1338     if (bit(val, i))
1339       return i;
1340   }
1341   return -1;
1342 }
1343 
1344 // Iterate through the debug registers; return the index of the first watchpoint
1345 // whose address matches.
1346 // As a side effect, the starting address as understood by the debugger is
1347 // returned which could be
1348 // different from 'addr' passed as an in/out argument.
GetHardwareWatchpointHit(nub_addr_t & addr)1349 uint32_t DNBArchMachARM::GetHardwareWatchpointHit(nub_addr_t &addr) {
1350   // Read the debug state
1351   kern_return_t kret = GetDBGState(true);
1352   // DumpDBGState(m_state.dbg);
1353   DNBLogThreadedIf(
1354       LOG_WATCHPOINTS,
1355       "DNBArchMachARM::GetHardwareWatchpointHit() GetDBGState() => 0x%8.8x.",
1356       kret);
1357   DNBLogThreadedIf(LOG_WATCHPOINTS,
1358                    "DNBArchMachARM::GetHardwareWatchpointHit() addr = 0x%llx",
1359                    (uint64_t)addr);
1360 
1361 // This is the watchpoint value to match against, i.e., word address.
1362 #if defined(WATCHPOINTS_ARE_DWORD)
1363   nub_addr_t wp_val = addr & ~((nub_addr_t)7);
1364 #else
1365   nub_addr_t wp_val = addr & ~((nub_addr_t)3);
1366 #endif
1367   if (kret == KERN_SUCCESS) {
1368     DBG &debug_state = m_state.dbg;
1369     uint32_t i, num = NumSupportedHardwareWatchpoints();
1370     for (i = 0; i < num; ++i) {
1371       nub_addr_t wp_addr = GetWatchAddress(debug_state, i);
1372       DNBLogThreadedIf(LOG_WATCHPOINTS, "DNBArchMachARM::"
1373                                         "GetHardwareWatchpointHit() slot: %u "
1374                                         "(addr = 0x%llx).",
1375                        i, (uint64_t)wp_addr);
1376       if (wp_val == wp_addr) {
1377 #if defined(WATCHPOINTS_ARE_DWORD)
1378         uint32_t byte_mask = bits(debug_state.__wcr[i], 12, 5);
1379 #else
1380         uint32_t byte_mask = bits(debug_state.__wcr[i], 8, 5);
1381 #endif
1382 
1383         // Sanity check the byte_mask, first.
1384         if (LowestBitSet(byte_mask) < 0)
1385           continue;
1386 
1387         // Compute the starting address (from the point of view of the
1388         // debugger).
1389         addr = wp_addr + LowestBitSet(byte_mask);
1390         return i;
1391       }
1392     }
1393   }
1394   return INVALID_NUB_HW_INDEX;
1395 }
1396 
GetWatchpointAddressByIndex(uint32_t hw_index)1397 nub_addr_t DNBArchMachARM::GetWatchpointAddressByIndex(uint32_t hw_index) {
1398   kern_return_t kret = GetDBGState(true);
1399   if (kret != KERN_SUCCESS)
1400     return INVALID_NUB_ADDRESS;
1401   const uint32_t num = NumSupportedHardwareWatchpoints();
1402   if (hw_index >= num)
1403     return INVALID_NUB_ADDRESS;
1404   if (IsWatchpointEnabled(m_state.dbg, hw_index))
1405     return GetWatchAddress(m_state.dbg, hw_index);
1406   return INVALID_NUB_ADDRESS;
1407 }
1408 
IsWatchpointEnabled(const DBG & debug_state,uint32_t hw_index)1409 bool DNBArchMachARM::IsWatchpointEnabled(const DBG &debug_state,
1410                                          uint32_t hw_index) {
1411   // Watchpoint Control Registers, bitfield definitions
1412   // ...
1413   // Bits    Value    Description
1414   // [0]     0        Watchpoint disabled
1415   //         1        Watchpoint enabled.
1416   return (debug_state.__wcr[hw_index] & 1u);
1417 }
1418 
GetWatchAddress(const DBG & debug_state,uint32_t hw_index)1419 nub_addr_t DNBArchMachARM::GetWatchAddress(const DBG &debug_state,
1420                                            uint32_t hw_index) {
1421   // Watchpoint Value Registers, bitfield definitions
1422   // Bits        Description
1423   // [31:2]      Watchpoint value (word address, i.e., 4-byte aligned)
1424   // [1:0]       RAZ/SBZP
1425   return bits(debug_state.__wvr[hw_index], 31, 0);
1426 }
1427 
1428 // Register information definitions for 32 bit ARMV7.
1429 enum gpr_regnums {
1430   gpr_r0 = 0,
1431   gpr_r1,
1432   gpr_r2,
1433   gpr_r3,
1434   gpr_r4,
1435   gpr_r5,
1436   gpr_r6,
1437   gpr_r7,
1438   gpr_r8,
1439   gpr_r9,
1440   gpr_r10,
1441   gpr_r11,
1442   gpr_r12,
1443   gpr_sp,
1444   gpr_lr,
1445   gpr_pc,
1446   gpr_cpsr
1447 };
1448 
1449 enum {
1450   vfp_s0 = 0,
1451   vfp_s1,
1452   vfp_s2,
1453   vfp_s3,
1454   vfp_s4,
1455   vfp_s5,
1456   vfp_s6,
1457   vfp_s7,
1458   vfp_s8,
1459   vfp_s9,
1460   vfp_s10,
1461   vfp_s11,
1462   vfp_s12,
1463   vfp_s13,
1464   vfp_s14,
1465   vfp_s15,
1466   vfp_s16,
1467   vfp_s17,
1468   vfp_s18,
1469   vfp_s19,
1470   vfp_s20,
1471   vfp_s21,
1472   vfp_s22,
1473   vfp_s23,
1474   vfp_s24,
1475   vfp_s25,
1476   vfp_s26,
1477   vfp_s27,
1478   vfp_s28,
1479   vfp_s29,
1480   vfp_s30,
1481   vfp_s31,
1482   vfp_d0,
1483   vfp_d1,
1484   vfp_d2,
1485   vfp_d3,
1486   vfp_d4,
1487   vfp_d5,
1488   vfp_d6,
1489   vfp_d7,
1490   vfp_d8,
1491   vfp_d9,
1492   vfp_d10,
1493   vfp_d11,
1494   vfp_d12,
1495   vfp_d13,
1496   vfp_d14,
1497   vfp_d15,
1498   vfp_d16,
1499   vfp_d17,
1500   vfp_d18,
1501   vfp_d19,
1502   vfp_d20,
1503   vfp_d21,
1504   vfp_d22,
1505   vfp_d23,
1506   vfp_d24,
1507   vfp_d25,
1508   vfp_d26,
1509   vfp_d27,
1510   vfp_d28,
1511   vfp_d29,
1512   vfp_d30,
1513   vfp_d31,
1514   vfp_q0,
1515   vfp_q1,
1516   vfp_q2,
1517   vfp_q3,
1518   vfp_q4,
1519   vfp_q5,
1520   vfp_q6,
1521   vfp_q7,
1522   vfp_q8,
1523   vfp_q9,
1524   vfp_q10,
1525   vfp_q11,
1526   vfp_q12,
1527   vfp_q13,
1528   vfp_q14,
1529   vfp_q15,
1530 #if defined(__arm64__) || defined(__aarch64__)
1531   vfp_fpsr,
1532   vfp_fpcr,
1533 #else
1534   vfp_fpscr
1535 #endif
1536 };
1537 
1538 enum {
1539   exc_exception,
1540   exc_fsr,
1541   exc_far,
1542 };
1543 
1544 #define GPR_OFFSET_IDX(idx) (offsetof(DNBArchMachARM::GPR, __r[idx]))
1545 #define GPR_OFFSET_NAME(reg) (offsetof(DNBArchMachARM::GPR, __##reg))
1546 
1547 #define EXC_OFFSET(reg)                                                        \
1548   (offsetof(DNBArchMachARM::EXC, __##reg) +                                    \
1549    offsetof(DNBArchMachARM::Context, exc))
1550 
1551 // These macros will auto define the register name, alt name, register size,
1552 // register offset, encoding, format and native register. This ensures that
1553 // the register state structures are defined correctly and have the correct
1554 // sizes and offsets.
1555 #define DEFINE_GPR_IDX(idx, reg, alt, gen)                                     \
1556   {                                                                            \
1557     e_regSetGPR, gpr_##reg, #reg, alt, Uint, Hex, 4, GPR_OFFSET_IDX(idx),      \
1558         ehframe_##reg, dwarf_##reg, gen, INVALID_NUB_REGNUM, NULL, NULL        \
1559   }
1560 #define DEFINE_GPR_NAME(reg, alt, gen, inval)                                  \
1561   {                                                                            \
1562     e_regSetGPR, gpr_##reg, #reg, alt, Uint, Hex, 4, GPR_OFFSET_NAME(reg),     \
1563         ehframe_##reg, dwarf_##reg, gen, INVALID_NUB_REGNUM, NULL, inval       \
1564   }
1565 
1566 // In case we are debugging to a debug target that the ability to
1567 // change into the protected modes with folded registers (ABT, IRQ,
1568 // FIQ, SYS, USR, etc..), we should invalidate r8-r14 if the CPSR
1569 // gets modified.
1570 
1571 const char *g_invalidate_cpsr[] = {"r8",  "r9", "r10", "r11",
1572                                    "r12", "sp", "lr",  NULL};
1573 
1574 // General purpose registers
1575 const DNBRegisterInfo DNBArchMachARM::g_gpr_registers[] = {
1576     DEFINE_GPR_IDX(0, r0, "arg1", GENERIC_REGNUM_ARG1),
1577     DEFINE_GPR_IDX(1, r1, "arg2", GENERIC_REGNUM_ARG2),
1578     DEFINE_GPR_IDX(2, r2, "arg3", GENERIC_REGNUM_ARG3),
1579     DEFINE_GPR_IDX(3, r3, "arg4", GENERIC_REGNUM_ARG4),
1580     DEFINE_GPR_IDX(4, r4, NULL, INVALID_NUB_REGNUM),
1581     DEFINE_GPR_IDX(5, r5, NULL, INVALID_NUB_REGNUM),
1582     DEFINE_GPR_IDX(6, r6, NULL, INVALID_NUB_REGNUM),
1583     DEFINE_GPR_IDX(7, r7, "fp", GENERIC_REGNUM_FP),
1584     DEFINE_GPR_IDX(8, r8, NULL, INVALID_NUB_REGNUM),
1585     DEFINE_GPR_IDX(9, r9, NULL, INVALID_NUB_REGNUM),
1586     DEFINE_GPR_IDX(10, r10, NULL, INVALID_NUB_REGNUM),
1587     DEFINE_GPR_IDX(11, r11, NULL, INVALID_NUB_REGNUM),
1588     DEFINE_GPR_IDX(12, r12, NULL, INVALID_NUB_REGNUM),
1589     DEFINE_GPR_NAME(sp, "r13", GENERIC_REGNUM_SP, NULL),
1590     DEFINE_GPR_NAME(lr, "r14", GENERIC_REGNUM_RA, NULL),
1591     DEFINE_GPR_NAME(pc, "r15", GENERIC_REGNUM_PC, NULL),
1592     DEFINE_GPR_NAME(cpsr, "flags", GENERIC_REGNUM_FLAGS, g_invalidate_cpsr)};
1593 
1594 const char *g_contained_q0[]{"q0", NULL};
1595 const char *g_contained_q1[]{"q1", NULL};
1596 const char *g_contained_q2[]{"q2", NULL};
1597 const char *g_contained_q3[]{"q3", NULL};
1598 const char *g_contained_q4[]{"q4", NULL};
1599 const char *g_contained_q5[]{"q5", NULL};
1600 const char *g_contained_q6[]{"q6", NULL};
1601 const char *g_contained_q7[]{"q7", NULL};
1602 const char *g_contained_q8[]{"q8", NULL};
1603 const char *g_contained_q9[]{"q9", NULL};
1604 const char *g_contained_q10[]{"q10", NULL};
1605 const char *g_contained_q11[]{"q11", NULL};
1606 const char *g_contained_q12[]{"q12", NULL};
1607 const char *g_contained_q13[]{"q13", NULL};
1608 const char *g_contained_q14[]{"q14", NULL};
1609 const char *g_contained_q15[]{"q15", NULL};
1610 
1611 const char *g_invalidate_q0[]{"q0", "d0", "d1", "s0", "s1", "s2", "s3", NULL};
1612 const char *g_invalidate_q1[]{"q1", "d2", "d3", "s4", "s5", "s6", "s7", NULL};
1613 const char *g_invalidate_q2[]{"q2", "d4", "d5", "s8", "s9", "s10", "s11", NULL};
1614 const char *g_invalidate_q3[]{"q3",  "d6",  "d7",  "s12",
1615                               "s13", "s14", "s15", NULL};
1616 const char *g_invalidate_q4[]{"q4",  "d8",  "d9",  "s16",
1617                               "s17", "s18", "s19", NULL};
1618 const char *g_invalidate_q5[]{"q5",  "d10", "d11", "s20",
1619                               "s21", "s22", "s23", NULL};
1620 const char *g_invalidate_q6[]{"q6",  "d12", "d13", "s24",
1621                               "s25", "s26", "s27", NULL};
1622 const char *g_invalidate_q7[]{"q7",  "d14", "d15", "s28",
1623                               "s29", "s30", "s31", NULL};
1624 const char *g_invalidate_q8[]{"q8", "d16", "d17", NULL};
1625 const char *g_invalidate_q9[]{"q9", "d18", "d19", NULL};
1626 const char *g_invalidate_q10[]{"q10", "d20", "d21", NULL};
1627 const char *g_invalidate_q11[]{"q11", "d22", "d23", NULL};
1628 const char *g_invalidate_q12[]{"q12", "d24", "d25", NULL};
1629 const char *g_invalidate_q13[]{"q13", "d26", "d27", NULL};
1630 const char *g_invalidate_q14[]{"q14", "d28", "d29", NULL};
1631 const char *g_invalidate_q15[]{"q15", "d30", "d31", NULL};
1632 
1633 #define VFP_S_OFFSET_IDX(idx)                                                  \
1634   (((idx) % 4) * 4) // offset into q reg: 0, 4, 8, 12
1635 #define VFP_D_OFFSET_IDX(idx) (((idx) % 2) * 8) // offset into q reg: 0, 8
1636 #define VFP_Q_OFFSET_IDX(idx) (VFP_S_OFFSET_IDX((idx)*4))
1637 
1638 #define VFP_OFFSET_NAME(reg)                                                   \
1639   (offsetof(DNBArchMachARM::FPU, __##reg) +                                    \
1640    offsetof(DNBArchMachARM::Context, vfp))
1641 
1642 #define FLOAT_FORMAT Float
1643 
1644 #define DEFINE_VFP_S_IDX(idx)                                                  \
1645   e_regSetVFP, vfp_s##idx, "s" #idx, NULL, IEEE754, FLOAT_FORMAT, 4,           \
1646       VFP_S_OFFSET_IDX(idx), INVALID_NUB_REGNUM, dwarf_s##idx,                 \
1647       INVALID_NUB_REGNUM, INVALID_NUB_REGNUM
1648 #define DEFINE_VFP_D_IDX(idx)                                                  \
1649   e_regSetVFP, vfp_d##idx, "d" #idx, NULL, IEEE754, FLOAT_FORMAT, 8,           \
1650       VFP_D_OFFSET_IDX(idx), INVALID_NUB_REGNUM, dwarf_d##idx,                 \
1651       INVALID_NUB_REGNUM, INVALID_NUB_REGNUM
1652 #define DEFINE_VFP_Q_IDX(idx)                                                  \
1653   e_regSetVFP, vfp_q##idx, "q" #idx, NULL, Vector, VectorOfUInt8, 16,          \
1654       VFP_Q_OFFSET_IDX(idx), INVALID_NUB_REGNUM, dwarf_q##idx,                 \
1655       INVALID_NUB_REGNUM, INVALID_NUB_REGNUM
1656 
1657 // Floating point registers
1658 const DNBRegisterInfo DNBArchMachARM::g_vfp_registers[] = {
1659     {DEFINE_VFP_S_IDX(0), g_contained_q0, g_invalidate_q0},
1660     {DEFINE_VFP_S_IDX(1), g_contained_q0, g_invalidate_q0},
1661     {DEFINE_VFP_S_IDX(2), g_contained_q0, g_invalidate_q0},
1662     {DEFINE_VFP_S_IDX(3), g_contained_q0, g_invalidate_q0},
1663     {DEFINE_VFP_S_IDX(4), g_contained_q1, g_invalidate_q1},
1664     {DEFINE_VFP_S_IDX(5), g_contained_q1, g_invalidate_q1},
1665     {DEFINE_VFP_S_IDX(6), g_contained_q1, g_invalidate_q1},
1666     {DEFINE_VFP_S_IDX(7), g_contained_q1, g_invalidate_q1},
1667     {DEFINE_VFP_S_IDX(8), g_contained_q2, g_invalidate_q2},
1668     {DEFINE_VFP_S_IDX(9), g_contained_q2, g_invalidate_q2},
1669     {DEFINE_VFP_S_IDX(10), g_contained_q2, g_invalidate_q2},
1670     {DEFINE_VFP_S_IDX(11), g_contained_q2, g_invalidate_q2},
1671     {DEFINE_VFP_S_IDX(12), g_contained_q3, g_invalidate_q3},
1672     {DEFINE_VFP_S_IDX(13), g_contained_q3, g_invalidate_q3},
1673     {DEFINE_VFP_S_IDX(14), g_contained_q3, g_invalidate_q3},
1674     {DEFINE_VFP_S_IDX(15), g_contained_q3, g_invalidate_q3},
1675     {DEFINE_VFP_S_IDX(16), g_contained_q4, g_invalidate_q4},
1676     {DEFINE_VFP_S_IDX(17), g_contained_q4, g_invalidate_q4},
1677     {DEFINE_VFP_S_IDX(18), g_contained_q4, g_invalidate_q4},
1678     {DEFINE_VFP_S_IDX(19), g_contained_q4, g_invalidate_q4},
1679     {DEFINE_VFP_S_IDX(20), g_contained_q5, g_invalidate_q5},
1680     {DEFINE_VFP_S_IDX(21), g_contained_q5, g_invalidate_q5},
1681     {DEFINE_VFP_S_IDX(22), g_contained_q5, g_invalidate_q5},
1682     {DEFINE_VFP_S_IDX(23), g_contained_q5, g_invalidate_q5},
1683     {DEFINE_VFP_S_IDX(24), g_contained_q6, g_invalidate_q6},
1684     {DEFINE_VFP_S_IDX(25), g_contained_q6, g_invalidate_q6},
1685     {DEFINE_VFP_S_IDX(26), g_contained_q6, g_invalidate_q6},
1686     {DEFINE_VFP_S_IDX(27), g_contained_q6, g_invalidate_q6},
1687     {DEFINE_VFP_S_IDX(28), g_contained_q7, g_invalidate_q7},
1688     {DEFINE_VFP_S_IDX(29), g_contained_q7, g_invalidate_q7},
1689     {DEFINE_VFP_S_IDX(30), g_contained_q7, g_invalidate_q7},
1690     {DEFINE_VFP_S_IDX(31), g_contained_q7, g_invalidate_q7},
1691 
1692     {DEFINE_VFP_D_IDX(0), g_contained_q0, g_invalidate_q0},
1693     {DEFINE_VFP_D_IDX(1), g_contained_q0, g_invalidate_q0},
1694     {DEFINE_VFP_D_IDX(2), g_contained_q1, g_invalidate_q1},
1695     {DEFINE_VFP_D_IDX(3), g_contained_q1, g_invalidate_q1},
1696     {DEFINE_VFP_D_IDX(4), g_contained_q2, g_invalidate_q2},
1697     {DEFINE_VFP_D_IDX(5), g_contained_q2, g_invalidate_q2},
1698     {DEFINE_VFP_D_IDX(6), g_contained_q3, g_invalidate_q3},
1699     {DEFINE_VFP_D_IDX(7), g_contained_q3, g_invalidate_q3},
1700     {DEFINE_VFP_D_IDX(8), g_contained_q4, g_invalidate_q4},
1701     {DEFINE_VFP_D_IDX(9), g_contained_q4, g_invalidate_q4},
1702     {DEFINE_VFP_D_IDX(10), g_contained_q5, g_invalidate_q5},
1703     {DEFINE_VFP_D_IDX(11), g_contained_q5, g_invalidate_q5},
1704     {DEFINE_VFP_D_IDX(12), g_contained_q6, g_invalidate_q6},
1705     {DEFINE_VFP_D_IDX(13), g_contained_q6, g_invalidate_q6},
1706     {DEFINE_VFP_D_IDX(14), g_contained_q7, g_invalidate_q7},
1707     {DEFINE_VFP_D_IDX(15), g_contained_q7, g_invalidate_q7},
1708     {DEFINE_VFP_D_IDX(16), g_contained_q8, g_invalidate_q8},
1709     {DEFINE_VFP_D_IDX(17), g_contained_q8, g_invalidate_q8},
1710     {DEFINE_VFP_D_IDX(18), g_contained_q9, g_invalidate_q9},
1711     {DEFINE_VFP_D_IDX(19), g_contained_q9, g_invalidate_q9},
1712     {DEFINE_VFP_D_IDX(20), g_contained_q10, g_invalidate_q10},
1713     {DEFINE_VFP_D_IDX(21), g_contained_q10, g_invalidate_q10},
1714     {DEFINE_VFP_D_IDX(22), g_contained_q11, g_invalidate_q11},
1715     {DEFINE_VFP_D_IDX(23), g_contained_q11, g_invalidate_q11},
1716     {DEFINE_VFP_D_IDX(24), g_contained_q12, g_invalidate_q12},
1717     {DEFINE_VFP_D_IDX(25), g_contained_q12, g_invalidate_q12},
1718     {DEFINE_VFP_D_IDX(26), g_contained_q13, g_invalidate_q13},
1719     {DEFINE_VFP_D_IDX(27), g_contained_q13, g_invalidate_q13},
1720     {DEFINE_VFP_D_IDX(28), g_contained_q14, g_invalidate_q14},
1721     {DEFINE_VFP_D_IDX(29), g_contained_q14, g_invalidate_q14},
1722     {DEFINE_VFP_D_IDX(30), g_contained_q15, g_invalidate_q15},
1723     {DEFINE_VFP_D_IDX(31), g_contained_q15, g_invalidate_q15},
1724 
1725     {DEFINE_VFP_Q_IDX(0), NULL, g_invalidate_q0},
1726     {DEFINE_VFP_Q_IDX(1), NULL, g_invalidate_q1},
1727     {DEFINE_VFP_Q_IDX(2), NULL, g_invalidate_q2},
1728     {DEFINE_VFP_Q_IDX(3), NULL, g_invalidate_q3},
1729     {DEFINE_VFP_Q_IDX(4), NULL, g_invalidate_q4},
1730     {DEFINE_VFP_Q_IDX(5), NULL, g_invalidate_q5},
1731     {DEFINE_VFP_Q_IDX(6), NULL, g_invalidate_q6},
1732     {DEFINE_VFP_Q_IDX(7), NULL, g_invalidate_q7},
1733     {DEFINE_VFP_Q_IDX(8), NULL, g_invalidate_q8},
1734     {DEFINE_VFP_Q_IDX(9), NULL, g_invalidate_q9},
1735     {DEFINE_VFP_Q_IDX(10), NULL, g_invalidate_q10},
1736     {DEFINE_VFP_Q_IDX(11), NULL, g_invalidate_q11},
1737     {DEFINE_VFP_Q_IDX(12), NULL, g_invalidate_q12},
1738     {DEFINE_VFP_Q_IDX(13), NULL, g_invalidate_q13},
1739     {DEFINE_VFP_Q_IDX(14), NULL, g_invalidate_q14},
1740     {DEFINE_VFP_Q_IDX(15), NULL, g_invalidate_q15},
1741 
1742 #if defined(__arm64__) || defined(__aarch64__)
1743     {e_regSetVFP, vfp_fpsr, "fpsr", NULL, Uint, Hex, 4, VFP_OFFSET_NAME(fpsr),
1744      INVALID_NUB_REGNUM, INVALID_NUB_REGNUM, INVALID_NUB_REGNUM,
1745      INVALID_NUB_REGNUM, NULL, NULL},
1746     {e_regSetVFP, vfp_fpcr, "fpcr", NULL, Uint, Hex, 4, VFP_OFFSET_NAME(fpcr),
1747      INVALID_NUB_REGNUM, INVALID_NUB_REGNUM, INVALID_NUB_REGNUM,
1748      INVALID_NUB_REGNUM, NULL, NULL}
1749 #else
1750     {e_regSetVFP, vfp_fpscr, "fpscr", NULL, Uint, Hex, 4,
1751      VFP_OFFSET_NAME(fpscr), INVALID_NUB_REGNUM, INVALID_NUB_REGNUM,
1752      INVALID_NUB_REGNUM, INVALID_NUB_REGNUM, NULL, NULL}
1753 #endif
1754 };
1755 
1756 // Exception registers
1757 
1758 const DNBRegisterInfo DNBArchMachARM::g_exc_registers[] = {
1759     {e_regSetVFP, exc_exception, "exception", NULL, Uint, Hex, 4,
1760      EXC_OFFSET(exception), INVALID_NUB_REGNUM, INVALID_NUB_REGNUM,
1761      INVALID_NUB_REGNUM, INVALID_NUB_REGNUM},
1762     {e_regSetVFP, exc_fsr, "fsr", NULL, Uint, Hex, 4, EXC_OFFSET(fsr),
1763      INVALID_NUB_REGNUM, INVALID_NUB_REGNUM, INVALID_NUB_REGNUM,
1764      INVALID_NUB_REGNUM},
1765     {e_regSetVFP, exc_far, "far", NULL, Uint, Hex, 4, EXC_OFFSET(far),
1766      INVALID_NUB_REGNUM, INVALID_NUB_REGNUM, INVALID_NUB_REGNUM,
1767      INVALID_NUB_REGNUM}};
1768 
1769 // Number of registers in each register set
1770 const size_t DNBArchMachARM::k_num_gpr_registers =
1771     sizeof(g_gpr_registers) / sizeof(DNBRegisterInfo);
1772 const size_t DNBArchMachARM::k_num_vfp_registers =
1773     sizeof(g_vfp_registers) / sizeof(DNBRegisterInfo);
1774 const size_t DNBArchMachARM::k_num_exc_registers =
1775     sizeof(g_exc_registers) / sizeof(DNBRegisterInfo);
1776 const size_t DNBArchMachARM::k_num_all_registers =
1777     k_num_gpr_registers + k_num_vfp_registers + k_num_exc_registers;
1778 
1779 // Register set definitions. The first definitions at register set index
1780 // of zero is for all registers, followed by other registers sets. The
1781 // register information for the all register set need not be filled in.
1782 const DNBRegisterSetInfo DNBArchMachARM::g_reg_sets[] = {
1783     {"ARM Registers", NULL, k_num_all_registers},
1784     {"General Purpose Registers", g_gpr_registers, k_num_gpr_registers},
1785     {"Floating Point Registers", g_vfp_registers, k_num_vfp_registers},
1786     {"Exception State Registers", g_exc_registers, k_num_exc_registers}};
1787 // Total number of register sets for this architecture
1788 const size_t DNBArchMachARM::k_num_register_sets =
1789     sizeof(g_reg_sets) / sizeof(DNBRegisterSetInfo);
1790 
1791 const DNBRegisterSetInfo *
GetRegisterSetInfo(nub_size_t * num_reg_sets)1792 DNBArchMachARM::GetRegisterSetInfo(nub_size_t *num_reg_sets) {
1793   *num_reg_sets = k_num_register_sets;
1794   return g_reg_sets;
1795 }
1796 
GetRegisterValue(uint32_t set,uint32_t reg,DNBRegisterValue * value)1797 bool DNBArchMachARM::GetRegisterValue(uint32_t set, uint32_t reg,
1798                                       DNBRegisterValue *value) {
1799   if (set == REGISTER_SET_GENERIC) {
1800     switch (reg) {
1801     case GENERIC_REGNUM_PC: // Program Counter
1802       set = e_regSetGPR;
1803       reg = gpr_pc;
1804       break;
1805 
1806     case GENERIC_REGNUM_SP: // Stack Pointer
1807       set = e_regSetGPR;
1808       reg = gpr_sp;
1809       break;
1810 
1811     case GENERIC_REGNUM_FP: // Frame Pointer
1812       set = e_regSetGPR;
1813       reg = gpr_r7; // is this the right reg?
1814       break;
1815 
1816     case GENERIC_REGNUM_RA: // Return Address
1817       set = e_regSetGPR;
1818       reg = gpr_lr;
1819       break;
1820 
1821     case GENERIC_REGNUM_FLAGS: // Processor flags register
1822       set = e_regSetGPR;
1823       reg = gpr_cpsr;
1824       break;
1825 
1826     default:
1827       return false;
1828     }
1829   }
1830 
1831   if (GetRegisterState(set, false) != KERN_SUCCESS)
1832     return false;
1833 
1834   const DNBRegisterInfo *regInfo = m_thread->GetRegisterInfo(set, reg);
1835   if (regInfo) {
1836     value->info = *regInfo;
1837     switch (set) {
1838     case e_regSetGPR:
1839       if (reg < k_num_gpr_registers) {
1840         value->value.uint32 = m_state.context.gpr.__r[reg];
1841         return true;
1842       }
1843       break;
1844 
1845     case e_regSetVFP:
1846       // "reg" is an index into the floating point register set at this point.
1847       // We need to translate it up so entry 0 in the fp reg set is the same as
1848       // vfp_s0
1849       // in the enumerated values for case statement below.
1850       if (reg >= vfp_s0 && reg <= vfp_s31) {
1851 #if defined(__arm64__) || defined(__aarch64__)
1852         uint32_t *s_reg =
1853             ((uint32_t *)&m_state.context.vfp.__v[0]) + (reg - vfp_s0);
1854         memcpy(&value->value.v_uint8, s_reg, 4);
1855 #else
1856         value->value.uint32 = m_state.context.vfp.__r[reg];
1857 #endif
1858         return true;
1859       } else if (reg >= vfp_d0 && reg <= vfp_d31) {
1860 #if defined(__arm64__) || defined(__aarch64__)
1861         uint64_t *d_reg =
1862             ((uint64_t *)&m_state.context.vfp.__v[0]) + (reg - vfp_d0);
1863         memcpy(&value->value.v_uint8, d_reg, 8);
1864 #else
1865         uint32_t d_reg_idx = reg - vfp_d0;
1866         uint32_t s_reg_idx = d_reg_idx * 2;
1867         value->value.v_sint32[0] = m_state.context.vfp.__r[s_reg_idx + 0];
1868         value->value.v_sint32[1] = m_state.context.vfp.__r[s_reg_idx + 1];
1869 #endif
1870         return true;
1871       } else if (reg >= vfp_q0 && reg <= vfp_q15) {
1872 #if defined(__arm64__) || defined(__aarch64__)
1873         memcpy(&value->value.v_uint8,
1874                (uint8_t *)&m_state.context.vfp.__v[reg - vfp_q0], 16);
1875 #else
1876         uint32_t s_reg_idx = (reg - vfp_q0) * 4;
1877         memcpy(&value->value.v_uint8,
1878                (uint8_t *)&m_state.context.vfp.__r[s_reg_idx], 16);
1879 #endif
1880         return true;
1881       }
1882 #if defined(__arm64__) || defined(__aarch64__)
1883       else if (reg == vfp_fpsr) {
1884         value->value.uint32 = m_state.context.vfp.__fpsr;
1885         return true;
1886       } else if (reg == vfp_fpcr) {
1887         value->value.uint32 = m_state.context.vfp.__fpcr;
1888         return true;
1889       }
1890 #else
1891       else if (reg == vfp_fpscr) {
1892         value->value.uint32 = m_state.context.vfp.__fpscr;
1893         return true;
1894       }
1895 #endif
1896       break;
1897 
1898     case e_regSetEXC:
1899       if (reg < k_num_exc_registers) {
1900         value->value.uint32 = (&m_state.context.exc.__exception)[reg];
1901         return true;
1902       }
1903       break;
1904     }
1905   }
1906   return false;
1907 }
1908 
SetRegisterValue(uint32_t set,uint32_t reg,const DNBRegisterValue * value)1909 bool DNBArchMachARM::SetRegisterValue(uint32_t set, uint32_t reg,
1910                                       const DNBRegisterValue *value) {
1911   if (set == REGISTER_SET_GENERIC) {
1912     switch (reg) {
1913     case GENERIC_REGNUM_PC: // Program Counter
1914       set = e_regSetGPR;
1915       reg = gpr_pc;
1916       break;
1917 
1918     case GENERIC_REGNUM_SP: // Stack Pointer
1919       set = e_regSetGPR;
1920       reg = gpr_sp;
1921       break;
1922 
1923     case GENERIC_REGNUM_FP: // Frame Pointer
1924       set = e_regSetGPR;
1925       reg = gpr_r7;
1926       break;
1927 
1928     case GENERIC_REGNUM_RA: // Return Address
1929       set = e_regSetGPR;
1930       reg = gpr_lr;
1931       break;
1932 
1933     case GENERIC_REGNUM_FLAGS: // Processor flags register
1934       set = e_regSetGPR;
1935       reg = gpr_cpsr;
1936       break;
1937 
1938     default:
1939       return false;
1940     }
1941   }
1942 
1943   if (GetRegisterState(set, false) != KERN_SUCCESS)
1944     return false;
1945 
1946   bool success = false;
1947   const DNBRegisterInfo *regInfo = m_thread->GetRegisterInfo(set, reg);
1948   if (regInfo) {
1949     switch (set) {
1950     case e_regSetGPR:
1951       if (reg < k_num_gpr_registers) {
1952         m_state.context.gpr.__r[reg] = value->value.uint32;
1953         success = true;
1954       }
1955       break;
1956 
1957     case e_regSetVFP:
1958       // "reg" is an index into the floating point register set at this point.
1959       // We need to translate it up so entry 0 in the fp reg set is the same as
1960       // vfp_s0
1961       // in the enumerated values for case statement below.
1962       if (reg >= vfp_s0 && reg <= vfp_s31) {
1963 #if defined(__arm64__) || defined(__aarch64__)
1964         uint32_t *s_reg =
1965             ((uint32_t *)&m_state.context.vfp.__v[0]) + (reg - vfp_s0);
1966         memcpy(s_reg, &value->value.v_uint8, 4);
1967 #else
1968         m_state.context.vfp.__r[reg] = value->value.uint32;
1969 #endif
1970         success = true;
1971       } else if (reg >= vfp_d0 && reg <= vfp_d31) {
1972 #if defined(__arm64__) || defined(__aarch64__)
1973         uint64_t *d_reg =
1974             ((uint64_t *)&m_state.context.vfp.__v[0]) + (reg - vfp_d0);
1975         memcpy(d_reg, &value->value.v_uint8, 8);
1976 #else
1977         uint32_t d_reg_idx = reg - vfp_d0;
1978         uint32_t s_reg_idx = d_reg_idx * 2;
1979         m_state.context.vfp.__r[s_reg_idx + 0] = value->value.v_sint32[0];
1980         m_state.context.vfp.__r[s_reg_idx + 1] = value->value.v_sint32[1];
1981 #endif
1982         success = true;
1983       } else if (reg >= vfp_q0 && reg <= vfp_q15) {
1984 #if defined(__arm64__) || defined(__aarch64__)
1985         memcpy((uint8_t *)&m_state.context.vfp.__v[reg - vfp_q0],
1986                &value->value.v_uint8, 16);
1987 #else
1988         uint32_t s_reg_idx = (reg - vfp_q0) * 4;
1989         memcpy((uint8_t *)&m_state.context.vfp.__r[s_reg_idx],
1990                &value->value.v_uint8, 16);
1991 #endif
1992         success = true;
1993       }
1994 #if defined(__arm64__) || defined(__aarch64__)
1995       else if (reg == vfp_fpsr) {
1996         m_state.context.vfp.__fpsr = value->value.uint32;
1997         success = true;
1998       } else if (reg == vfp_fpcr) {
1999         m_state.context.vfp.__fpcr = value->value.uint32;
2000         success = true;
2001       }
2002 #else
2003       else if (reg == vfp_fpscr) {
2004         m_state.context.vfp.__fpscr = value->value.uint32;
2005         success = true;
2006       }
2007 #endif
2008       break;
2009 
2010     case e_regSetEXC:
2011       if (reg < k_num_exc_registers) {
2012         (&m_state.context.exc.__exception)[reg] = value->value.uint32;
2013         success = true;
2014       }
2015       break;
2016     }
2017   }
2018   if (success)
2019     return SetRegisterState(set) == KERN_SUCCESS;
2020   return false;
2021 }
2022 
GetRegisterState(int set,bool force)2023 kern_return_t DNBArchMachARM::GetRegisterState(int set, bool force) {
2024   switch (set) {
2025   case e_regSetALL:
2026     return GetGPRState(force) | GetVFPState(force) | GetEXCState(force) |
2027            GetDBGState(force);
2028   case e_regSetGPR:
2029     return GetGPRState(force);
2030   case e_regSetVFP:
2031     return GetVFPState(force);
2032   case e_regSetEXC:
2033     return GetEXCState(force);
2034   case e_regSetDBG:
2035     return GetDBGState(force);
2036   default:
2037     break;
2038   }
2039   return KERN_INVALID_ARGUMENT;
2040 }
2041 
SetRegisterState(int set)2042 kern_return_t DNBArchMachARM::SetRegisterState(int set) {
2043   // Make sure we have a valid context to set.
2044   kern_return_t err = GetRegisterState(set, false);
2045   if (err != KERN_SUCCESS)
2046     return err;
2047 
2048   switch (set) {
2049   case e_regSetALL:
2050     return SetGPRState() | SetVFPState() | SetEXCState() | SetDBGState(false);
2051   case e_regSetGPR:
2052     return SetGPRState();
2053   case e_regSetVFP:
2054     return SetVFPState();
2055   case e_regSetEXC:
2056     return SetEXCState();
2057   case e_regSetDBG:
2058     return SetDBGState(false);
2059   default:
2060     break;
2061   }
2062   return KERN_INVALID_ARGUMENT;
2063 }
2064 
RegisterSetStateIsValid(int set) const2065 bool DNBArchMachARM::RegisterSetStateIsValid(int set) const {
2066   return m_state.RegsAreValid(set);
2067 }
2068 
GetRegisterContext(void * buf,nub_size_t buf_len)2069 nub_size_t DNBArchMachARM::GetRegisterContext(void *buf, nub_size_t buf_len) {
2070   nub_size_t size = sizeof(m_state.context.gpr) + sizeof(m_state.context.vfp) +
2071                     sizeof(m_state.context.exc);
2072 
2073   if (buf && buf_len) {
2074     if (size > buf_len)
2075       size = buf_len;
2076 
2077     bool force = false;
2078     if (GetGPRState(force) | GetVFPState(force) | GetEXCState(force))
2079       return 0;
2080 
2081     // Copy each struct individually to avoid any padding that might be between
2082     // the structs in m_state.context
2083     uint8_t *p = (uint8_t *)buf;
2084     ::memcpy(p, &m_state.context.gpr, sizeof(m_state.context.gpr));
2085     p += sizeof(m_state.context.gpr);
2086     ::memcpy(p, &m_state.context.vfp, sizeof(m_state.context.vfp));
2087     p += sizeof(m_state.context.vfp);
2088     ::memcpy(p, &m_state.context.exc, sizeof(m_state.context.exc));
2089     p += sizeof(m_state.context.exc);
2090 
2091     size_t bytes_written = p - (uint8_t *)buf;
2092     UNUSED_IF_ASSERT_DISABLED(bytes_written);
2093     assert(bytes_written == size);
2094   }
2095   DNBLogThreadedIf(
2096       LOG_THREAD,
2097       "DNBArchMachARM::GetRegisterContext (buf = %p, len = %llu) => %llu", buf,
2098       (uint64_t)buf_len, (uint64_t)size);
2099   // Return the size of the register context even if NULL was passed in
2100   return size;
2101 }
2102 
SetRegisterContext(const void * buf,nub_size_t buf_len)2103 nub_size_t DNBArchMachARM::SetRegisterContext(const void *buf,
2104                                               nub_size_t buf_len) {
2105   nub_size_t size = sizeof(m_state.context.gpr) + sizeof(m_state.context.vfp) +
2106                     sizeof(m_state.context.exc);
2107 
2108   if (buf == NULL || buf_len == 0)
2109     size = 0;
2110 
2111   if (size) {
2112     if (size > buf_len)
2113       size = buf_len;
2114 
2115     // Copy each struct individually to avoid any padding that might be between
2116     // the structs in m_state.context
2117     uint8_t *p = (uint8_t *)buf;
2118     ::memcpy(&m_state.context.gpr, p, sizeof(m_state.context.gpr));
2119     p += sizeof(m_state.context.gpr);
2120     ::memcpy(&m_state.context.vfp, p, sizeof(m_state.context.vfp));
2121     p += sizeof(m_state.context.vfp);
2122     ::memcpy(&m_state.context.exc, p, sizeof(m_state.context.exc));
2123     p += sizeof(m_state.context.exc);
2124 
2125     size_t bytes_written = p - (uint8_t *)buf;
2126     UNUSED_IF_ASSERT_DISABLED(bytes_written);
2127     assert(bytes_written == size);
2128 
2129     if (SetGPRState() | SetVFPState() | SetEXCState())
2130       return 0;
2131   }
2132   DNBLogThreadedIf(
2133       LOG_THREAD,
2134       "DNBArchMachARM::SetRegisterContext (buf = %p, len = %llu) => %llu", buf,
2135       (uint64_t)buf_len, (uint64_t)size);
2136   return size;
2137 }
2138 
SaveRegisterState()2139 uint32_t DNBArchMachARM::SaveRegisterState() {
2140   kern_return_t kret = ::thread_abort_safely(m_thread->MachPortNumber());
2141   DNBLogThreadedIf(
2142       LOG_THREAD, "thread = 0x%4.4x calling thread_abort_safely (tid) => %u "
2143                   "(SetGPRState() for stop_count = %u)",
2144       m_thread->MachPortNumber(), kret, m_thread->Process()->StopCount());
2145 
2146   // Always re-read the registers because above we call thread_abort_safely();
2147   bool force = true;
2148 
2149   if ((kret = GetGPRState(force)) != KERN_SUCCESS) {
2150     DNBLogThreadedIf(LOG_THREAD, "DNBArchMachARM::SaveRegisterState () error: "
2151                                  "GPR regs failed to read: %u ",
2152                      kret);
2153   } else if ((kret = GetVFPState(force)) != KERN_SUCCESS) {
2154     DNBLogThreadedIf(LOG_THREAD, "DNBArchMachARM::SaveRegisterState () error: "
2155                                  "%s regs failed to read: %u",
2156                      "VFP", kret);
2157   } else {
2158     const uint32_t save_id = GetNextRegisterStateSaveID();
2159     m_saved_register_states[save_id] = m_state.context;
2160     return save_id;
2161   }
2162   return UINT32_MAX;
2163 }
2164 
RestoreRegisterState(uint32_t save_id)2165 bool DNBArchMachARM::RestoreRegisterState(uint32_t save_id) {
2166   SaveRegisterStates::iterator pos = m_saved_register_states.find(save_id);
2167   if (pos != m_saved_register_states.end()) {
2168     m_state.context.gpr = pos->second.gpr;
2169     m_state.context.vfp = pos->second.vfp;
2170     kern_return_t kret;
2171     bool success = true;
2172     if ((kret = SetGPRState()) != KERN_SUCCESS) {
2173       DNBLogThreadedIf(LOG_THREAD, "DNBArchMachARM::RestoreRegisterState "
2174                                    "(save_id = %u) error: GPR regs failed to "
2175                                    "write: %u",
2176                        save_id, kret);
2177       success = false;
2178     } else if ((kret = SetVFPState()) != KERN_SUCCESS) {
2179       DNBLogThreadedIf(LOG_THREAD, "DNBArchMachARM::RestoreRegisterState "
2180                                    "(save_id = %u) error: %s regs failed to "
2181                                    "write: %u",
2182                        save_id, "VFP", kret);
2183       success = false;
2184     }
2185     m_saved_register_states.erase(pos);
2186     return success;
2187   }
2188   return false;
2189 }
2190 
2191 #endif // #if defined (__arm__)
2192