GDB disassembly output is weird


Device - IPAD running IOS 9.3.3 ( ARM architecture 64 bit - jailbroken) When i try to disassemble the function , i get weird output with unrecognized instruction set such as vqrshl, svcge. How do i fix it? I would really appreciate your help.

Please see the gdb output below

gdb) disassemble
Dump of assembler code for function mach_msg_trap:
0x21f1f894 <mach_msg_trap+0>:   mov r12, sp
0x21f1f898 <mach_msg_trap+4>:   push    {r4, r5, r6, r8}
0x21f1f89c <mach_msg_trap+8>:   ldm r12, {r4, r5, r6}
0x21f1f8a0 <mach_msg_trap+12>:  mvn r12, #30    ; 0x1e
0x21f1f8a4 <mach_msg_trap+16>:  svc 0x00000080
0x21f1f8a8 <mach_msg_trap+20>:  pop {r4, r5, r6, r8}
0x21f1f8ac <mach_msg_trap+24>:  bx  lr
End of assembler dump.
(gdb) break -[AntiPiracyViewController isJailbroken]
Breakpoint 1 at 0x73314
(gdb) C
warning: Unrecognized osabi 0 in arm_set_osabi_from_host_info

Breakpoint 1, 0x00073314 in -[AntiPiracyViewController isJailbroken] ()
(gdb) disassemble
Dump of assembler code for function -[AntiPiracyViewController isJailbroken]:
0x00073314 <-[AntiPiracyViewController isJailbroken]+0>:    vqrshl.s8   <illegal reg q13.5>, q8, <illegal reg q8.5>
0x00073318 <-[AntiPiracyViewController isJailbroken]+4>:    svcge   0x00032148
0x0007331c <-[AntiPiracyViewController isJailbroken]+8>:    smlabteq    r0, r0, r2, pc
0x00073320 <-[AntiPiracyViewController isJailbroken]+12>:   adccs   pc, r2, r1, asr #4
0x00073324 <-[AntiPiracyViewController isJailbroken]+16>:   andeq   pc, r0, r0, asr #5
0x00073328 <-[AntiPiracyViewController isJailbroken]+20>:   ldrbtmi r4, [r8], #-1145
0x0007332c <-[AntiPiracyViewController isJailbroken]+24>:   stmdavs r0, {r0, r3, r11, sp, lr}
0x00073330 <-[AntiPiracyViewController isJailbroken]+28>:   cdp 0, 5, cr15, cr8, cr0, {0}
0x00073334 <-[AntiPiracyViewController isJailbroken]+32>:   msrcs   SPSR_f, r1, asr #4
0x00073338 <-[AntiPiracyViewController isJailbroken]+36>:   smlabteq    r0, r0, r2, pc
0x0007333c <-[AntiPiracyViewController isJailbroken]+40>:   rscscs  pc, r2, #268435460  ; 0x10000004
0x00073340 <-[AntiPiracyViewController isJailbroken]+44>:   vmvn.i32    q10, #589824    ; 0x00090000
0x00073344 <-[AntiPiracyViewController isJailbroken]+48>:   ldrbtmi r0, [r10], #-512
0x00073348 <-[AntiPiracyViewController isJailbroken]+52>:   undefined instruction 0xf0006809
0x0007334c <-[AntiPiracyViewController isJailbroken]+56>:   vceq.f32    q15, <illegal reg q0.5>, q6
0x00073350 <-[AntiPiracyViewController isJailbroken]+60>:   vorr.i32    q9, #0  ; 0x00000000
0x00073354 <-[AntiPiracyViewController isJailbroken]+64>:   strmi   r0, [r4], -r0, lsl #2
0x00073358 <-[AntiPiracyViewController isJailbroken]+68>:   rsbcs   pc, lr, r1, asr #4
0x0007335c <-[AntiPiracyViewController isJailbroken]+72>:   vmvn.i32    q10, #589824    ; 0x00090000
0x00073360 <-[AntiPiracyViewController isJailbroken]+76>:   ldrbtmi r0, [r8]
0x00073364 <-[AntiPiracyViewController isJailbroken]+80>:   stmdavs r0, {r0, r3, r11, sp, lr}
0x00073368 <-[AntiPiracyViewController isJailbroken]+84>:   cdp 0, 3, cr15, cr12, cr0, {0}
0x0007336c <-[AntiPiracyViewController isJailbroken]+88>:   undefined instruction 0xf000463f
0x00073370 <-[AntiPiracyViewController isJailbroken]+92>:   strtmi  lr, [r2], -r2, asr #28
0x00073374 <-[AntiPiracyViewController isJailbroken]+96>:   vmax.s8 d20, d1, d5
0x00073378 <-[AntiPiracyViewController isJailbroken]+100>:  vmvn.i32    d18, #2 ; 0x00000002
0x0007337c <-[AntiPiracyViewController isJailbroken]+104>:  ldrbtmi r0, [r8]
0x00073380 <-[AntiPiracyViewController isJailbroken]+108>:  strtmi  r6, [r8], -r1, lsl #16
0x00073384 <-[AntiPiracyViewController isJailbroken]+112>:  cdp 0, 2, cr15, cr14, cr0, {0}
0x00073388 <-[AntiPiracyViewController isJailbroken]+116>:  strtmi  r4, [r8], -r6, lsl #12
0x0007338c <-[AntiPiracyViewController isJailbroken]+120>:  cdp 0, 3, cr15, cr0, cr0, {0}
0x00073390 <-[AntiPiracyViewController isJailbroken]+124>:  undefined instruction 0xf0004620
0x00073394 <-[AntiPiracyViewController isJailbroken]+128>:  rscslt  lr, r0, #736    ; 0x2e0
0x00073398 <-[AntiPiracyViewController isJailbroken]+132>:  svclt   0x00182800
0x0007339c <-[AntiPiracyViewController isJailbroken]+136>:  ldcllt  0, cr2, [r0, #4]!
End of assembler dump.
asked on Stack Overflow Oct 7, 2016 by user1970157

0 Answers

Nobody has answered this question yet.

User contributions licensed under CC BY-SA 3.0