Reverse in a nutshell

In this preparatory chapter, we are going to cover the basics of reverse-engineering an executable file. If you are already familiar with binary file format, you can skip and directly go to the next chapter.

We are going to use the tiny ELF executable fibonacci as a running example, paving the way to the next chapter.

What is inside?

An executable file contains machine code instructions and data that the processor will operate, but also some metadata that instruct the operating system how to map the content in the process memory.

note

The content and encoding of these metadata are operating system dependent. The common ones are:

the Executable and Linkable Format (ELF) for Linux;
the Portable Executable (PE) for Windows;
Mach-O for MacOS.

Hexdump

The following gives you an overview of the file content as read by BINSEC. Next sections describe this information in detail.

tip

Hover block content to display section names or string constants.
Click on instruction to get the disassembly preview.

00000000000000100000002000000030000000400000005000000060000000700000008000000090000000a0000000b0000000c0000000d0000000e0000000f000000100000001100000012000000130000001400000015000000160000001700000018000000190000001a0000001b0000001c0000001d0000001e0000001f000000200000002100000022000000230000002400000025000000260000002700000028000000290000002a0000002b0000002c0000002d0000002e0000002f0000003000000031000000320000003300000034000000350000003600000037000000380

7f45 4c46 0201 0100 0000 0000 0000 0000 0200 3e00 0100 0000 e800 4000 0000 0000 4000 0000 0000 0000 1002 0000 0000 0000 0000 0000 4000 3800 0100 4000 0600 0500 0100 0000 0500 0000 7800 0000 0000 0000 7800 4000 0000 0000 7800 4000 0000 0000 c400 0000 0000 0000 c400 0000 0000 0000 0400 0000 0000 0000 31c0 4885 ff74 0fba 0100 0000 4892 4801 d048 ffcf 75f6 c390 31ff 0fb6 0685 c074 1c83 e830 0f88 8200 0000 3c09 777e 48ff c648 8d3c bf48 01ff 4801 c7eb ddc3 6690 6668 000a 4889 e666 5abb 0a00 0000 48ff ce31 d248 f7f3 80c2 3088 1648 85c0 75ee bf01 0000 0048 89e2 4829 f289 f80f 05c3 5f66 83ff 0275 1f48 89e7 488b 7708 e895 ffff ffe8 78ff ffff e8b3 ffff ff31 ffb8 3c00 0000 0f05 bf01 0000 0048 8d34 2529 0140 00ba 1300 0000 89f8 0f05 40b7 ffeb de55 7361 6765 3a20 6669 626f 6e61 6363 6920 4e0a 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0100 0000 0200 0100 9000 4000 0000 0000 2600 0000 0000 0000 0e00 0000 0200 0100 b800 4000 0000 0000 3000 0000 0000 0000 1a00 0000 1000 0100 e800 4000 0000 0000 0000 0000 0000 0000 2100 0000 1200 0100 7800 4000 0000 0000 1700 0000 0000 0000 0070 6172 7365 5f75 696e 7436 3400 6563 686f 5f75 696e 7436 3400 5f73 7461 7274 0066 6962 6f6e 6163 6369 0000 2e73 796d 7461 6200 2e73 7472 7461 6200 2e73 6873 7472 7461 6200 2e74 6578 7400 2e72 6f64 6174 6100 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 1b00 0000 0100 0000 0600 0000 0000 0000 7800 4000 0000 0000 7800 0000 0000 0000 b100 0000 0000 0000 0000 0000 0000 0000 0400 0000 0000 0000 0000 0000 0000 0000 2100 0000 0100 0000 0200 0000 0000 0000 2901 4000 0000 0000 2901 0000 0000 0000 1300 0000 0000 0000 0000 0000 0000 0000 0100 0000 0000 0000 0000 0000 0000 0000 0100 0000 0200 0000 0000 0000 0000 0000 0000 0000 0000 0000 4001 0000 0000 0000 7800 0000 0000 0000 0400 0000 0300 0000 0800 0000 0000 0000 1800 0000 0000 0000 0900 0000 0300 0000 0000 0000 0000 0000 0000 0000 0000 0000 b801 0000 0000 0000 2b00 0000 0000 0000 0000 0000 0000 0000 0100 0000 0000 0000 0000 0000 0000 0000 1100 0000 0300 0000 0000 0000 0000 0000 0000 0000 0000 0000 e301 0000 0000 0000 2900 0000 0000 0000 0000 0000 0000 0000 0100 0000 0000 0000 0000 0000 0000 0000

Legend
Headers Magic
Code Instructions
Read-Only Data Strings
Data Other Sections

Headers
Disassembly

ELF Header:
Class:               ELF64                        
Data:                2's complement, little endian
Type:                EXEC                         
Machine:             x86                        
Entry point address: 0x4000e8                     

Section Headers:
[Nr] Name      Type     Addr             Off    Size   ES Flg Lk Inf Al
[ 0]           NULL     0000000000000000 000000 000000 00      0   0  0
[ 1] .text     PROGBITS 0000000000400078 000078 0000b1 00  AX  0   0  4
[ 2] .rodata   PROGBITS 0000000000400129 000129 000013 00   A  0   0  1
[ 3] .symtab   SYMTAB   0000000000000000 000140 000078 18      4   3  8
[ 4] .strtab   STRTAB   0000000000000000 0001b8 00002b 00      0   0  1
[ 5] .shstrtab STRTAB   0000000000000000 0001e3 000029 00      0   0  1
Key to Flags:
W (write), A (alloc), X (execute), M (merge), S (strings), I (info),
L (link order), G (group), T (TLS), O (extra OS processing required)

Symbol table '.symtab' contains 5 entries:
Num:            Value Size Type   Bind   Section Name        
  0: 0000000000000000    0 NOTYPE LOCAL  UND                 
  1: 0000000000400090   38 FUNC   LOCAL  .text   parse_uint64
  2: 00000000004000b8   48 FUNC   LOCAL  .text   echo_uint64
  3: 00000000004000e8    0 NOTYPE GLOBAL .text   _start    
  4: 0000000000400078   23 FUNC   GLOBAL .text   fibonacci

Disassembly of section .text:
00400078 <fibonacci>:
  400078: 31 c0 xor %eax,%eax
0: %%0<1> := undef;
1: rax<64> := 0<64>;
2: of<1> := 0<1>;
3: sf<1> := 0<1>;
4: zf<1> := -1<1>;
5: af<1> := %%0<1>;
6: pf<1> := -1<1>;
7: cf<1> := 0<1>;
8: goto (0x40007a, 0) 
  40007a: 48 85 ff test %rdi,%rdi
0: %%0<1> :=
 !
 ((((rdi<64>{0} ^ rdi<64>{4}) ^ (rdi<64>{2} ^ rdi<64>{6})) ^
   ((rdi<64>{1} ^ rdi<64>{5}) ^ (rdi<64>{3} ^ rdi<64>{7}))));
1: %%1<1> := undef;
2: %%2<1> := (0<64> = rdi<64>);
3: %%3<1> := (rdi<64> <s 0<64>);
4: of<1> := 0<1>;
5: sf<1> := %%3<1>;
6: zf<1> := %%2<1>;
7: af<1> := %%1<1>;
8: pf<1> := %%0<1>;
9: cf<1> := 0<1>;
10: goto (0x40007d, 0) 
  40007d: 74 0f je 0x40008e
0: if zf<1> goto 2 else goto 1
1: goto (0x40007f, 0) 
2: goto (0x40008e, 0) 
  40007f: ba 01 00 00 00 mov $0x1,%edx
0: rdx<64> := 1<64>;
1: goto (0x400084, 0) 
  400084: 48 92 xchg %rax,%rdx
0: %%0<64> := rdx<64>;
1: %%1<64> := rax<64>;
2: rdx<64> := %%1<64>;
3: rax<64> := %%0<64>;
4: goto (0x400086, 0) 
  400086: 48 01 d0 add %rdx,%rax
0: %%0<64> := (rax<64> & rdx<64>);
1: %%1<64> := (rax<64> + rdx<64>);
2: %%2<64> := ! (%%1<64>);
3: %%3<1> :=
 (0x8000000000000000 =
  (0x8000000000000000 &
   (((rax<64> | rdx<64>) & %%2<64>) | (%%0<64> & %%1<64>))));
4: %%4<1> :=
 !
 ((((%%1<64>{0} ^ %%1<64>{4}) ^ (%%1<64>{2} ^ %%1<64>{6})) ^
   ((%%1<64>{1} ^ %%1<64>{5}) ^ (%%1<64>{3} ^ %%1<64>{7}))));
5: %%5<1> := undef;
6: %%6<1> := (0<64> = %%1<64>);
7: %%7<1> := (%%1<64> <s 0<64>);
8: %%8<1> :=
 (0x8000000000000000 =
  (0x8000000000000000 &
   ((%%0<64> & %%2<64>) | ((! (rax<64>) & ! (rdx<64>)) & %%1<64>))));
9: rax<64> := %%1<64>;
10: of<1> := %%8<1>;
11: sf<1> := %%7<1>;
12: zf<1> := %%6<1>;
13: af<1> := %%5<1>;
14: pf<1> := %%4<1>;
15: cf<1> := %%3<1>;
16: goto (0x400089, 0) 
  400089: 48 ff cf dec %rdi
0: %%0<64> := (rdi<64> - 1<64>);
1: %%1<1> :=
 !
 ((((%%0<64>{0} ^ %%0<64>{4}) ^ (%%0<64>{2} ^ %%0<64>{6})) ^
   ((%%0<64>{1} ^ %%0<64>{5}) ^ (%%0<64>{3} ^ %%0<64>{7}))));
2: %%2<1> := undef;
3: %%3<1> := (0<64> = %%0<64>);
4: %%4<1> := (%%0<64> <s 0<64>);
5: %%5<1> :=
 (0x8000000000000000 = (0x8000000000000000 & (rdi<64> & ! (%%0<64>))));
6: rdi<64> := %%0<64>;
7: of<1> := %%5<1>;
8: sf<1> := %%4<1>;
9: zf<1> := %%3<1>;
10: af<1> := %%2<1>;
11: pf<1> := %%1<1>;
12: goto (0x40008c, 0) 
  40008c: 75 f6 jne 0x400084
0: if ! (zf<1>) goto 2 else goto 1
1: goto (0x40008e, 0) 
2: goto (0x400084, 0) 
  40008e: c3 ret
0: %%0<64> := (rsp<64> + 8<64>);
1: %%1<64> := @[rsp<64>,<-,8];
2: rsp<64> := %%0<64>;
3: goto %%1<64> #return
  40008f: 90 nop
0: goto (0x400090, 0) 
00400090 <parse_uint64>:
  400090: 31 ff xor %edi,%edi
0: %%0<1> := undef;
1: rdi<64> := 0<64>;
2: of<1> := 0<1>;
3: sf<1> := 0<1>;
4: zf<1> := -1<1>;
5: af<1> := %%0<1>;
6: pf<1> := -1<1>;
7: cf<1> := 0<1>;
8: goto (0x400092, 0) 
  400092: 0f b6 06 movzbl (%rsi),%eax
0: %%0<64> := (uext64 @[rsi<64>,<-,1]);
1: rax<64> := %%0<64>;
2: goto (0x400095, 0) 
  400095: 85 c0 test %eax,%eax
0: %%0<32> := rax<64>{31..0};
1: %%1<1> :=
 !
 ((((rax<64>{0} ^ rax<64>{4}) ^ (rax<64>{2} ^ rax<64>{6})) ^
   ((rax<64>{1} ^ rax<64>{5}) ^ (rax<64>{3} ^ rax<64>{7}))));
2: %%2<1> := undef;
3: %%3<1> := (0<32> = %%0<32>);
4: %%4<1> := (%%0<32> <s 0<32>);
5: of<1> := 0<1>;
6: sf<1> := %%4<1>;
7: zf<1> := %%3<1>;
8: af<1> := %%2<1>;
9: pf<1> := %%1<1>;
10: cf<1> := 0<1>;
11: goto (0x400097, 0) 
  400097: 74 1c je 0x4000b5
0: if zf<1> goto 2 else goto 1
1: goto (0x400099, 0) 
2: goto (0x4000b5, 0) 
  400099: 83 e8 30 sub $0x30,%eax
0: %%0<32> := rax<64>{31..0};
1: %%1<32> := (%%0<32> - 48<32>);
2: %%2<1> := (0x80000000 = (0x80000000 & (! (%%0<32>) & %%1<32>)));
3: %%3<1> :=
 !
 ((((%%1<32>{0} ^ %%1<32>{4}) ^ (%%1<32>{2} ^ %%1<32>{6})) ^
   ((%%1<32>{1} ^ %%1<32>{5}) ^ (%%1<32>{3} ^ %%1<32>{7}))));
4: %%4<1> := undef;
5: %%5<1> := (0<32> = %%1<32>);
6: %%6<1> := (%%1<32> <s 0<32>);
7: %%7<1> := (0x80000000 = (0x80000000 & (%%0<32> & ! (%%1<32>))));
8: %%8<64> := (uext64 %%1<32>);
9: rax<64> := %%8<64>;
10: of<1> := %%7<1>;
11: sf<1> := %%6<1>;
12: zf<1> := %%5<1>;
13: af<1> := %%4<1>;
14: pf<1> := %%3<1>;
15: cf<1> := %%2<1>;
16: goto (0x40009c, 0) 
  40009c: 0f 88 82 00 00 00 js 0x400124
0: if sf<1> goto 2 else goto 1
1: goto (0x4000a2, 0) 
2: goto (0x400124, 0) 
  4000a2: 3c 09 cmp $0x9,%al
0: %%0<8> := rax<64>{7..0};
1: %%1<8> := (%%0<8> - 9<8>);
2: %%2<1> := (-128<8> = (-128<8> & (! (%%0<8>) & %%1<8>)));
3: %%3<1> :=
 !
 ((((%%1<8>{0} ^ %%1<8>{4}) ^ (%%1<8>{2} ^ %%1<8>{6})) ^
   ((%%1<8>{1} ^ %%1<8>{5}) ^ (%%1<8>{3} ^ %%1<8>{7}))));
4: %%4<1> := undef;
5: %%5<1> := (0<8> = %%1<8>);
6: %%6<1> := (%%1<8> <s 0<8>);
7: %%7<1> := (-128<8> = (-128<8> & (%%0<8> & ! (%%1<8>))));
8: of<1> := %%7<1>;
9: sf<1> := %%6<1>;
10: zf<1> := %%5<1>;
11: af<1> := %%4<1>;
12: pf<1> := %%3<1>;
13: cf<1> := %%2<1>;
14: goto (0x4000a4, 0) 
  4000a4: 77 7e ja 0x400124
0: if ! ((cf<1> | zf<1>)) goto 2 else goto 1
1: goto (0x4000a6, 0) 
2: goto (0x400124, 0) 
  4000a6: 48 ff c6 inc %rsi
0: %%0<64> := (rsi<64> + 1<64>);
1: %%1<1> :=
 !
 ((((%%0<64>{0} ^ %%0<64>{4}) ^ (%%0<64>{2} ^ %%0<64>{6})) ^
   ((%%0<64>{1} ^ %%0<64>{5}) ^ (%%0<64>{3} ^ %%0<64>{7}))));
2: %%2<1> := undef;
3: %%3<1> := (0<64> = %%0<64>);
4: %%4<1> := (%%0<64> <s 0<64>);
5: %%5<1> :=
 (0x8000000000000000 = (0x8000000000000000 & (! (rsi<64>) & %%0<64>)));
6: rsi<64> := %%0<64>;
7: of<1> := %%5<1>;
8: sf<1> := %%4<1>;
9: zf<1> := %%3<1>;
10: af<1> := %%2<1>;
11: pf<1> := %%1<1>;
12: goto (0x4000a9, 0) 
  4000a9: 48 8d 3c bf lea (%rdi,%rdi,4),%rdi
0: %%0<64> := (rdi<64> + (rdi<64> lsl 2<64>));
1: rdi<64> := %%0<64>;
2: goto (0x4000ad, 0) 
  4000ad: 48 01 ff add %rdi,%rdi
0: %%0<64> := (rdi<64> + rdi<64>);
1: %%1<64> := (rdi<64> & ! (%%0<64>));
2: %%2<1> :=
 (0x8000000000000000 =
  (0x8000000000000000 & (%%1<64> | (rdi<64> & %%0<64>))));
3: %%3<1> :=
 !
 ((((%%0<64>{0} ^ %%0<64>{4}) ^ (%%0<64>{2} ^ %%0<64>{6})) ^
   ((%%0<64>{1} ^ %%0<64>{5}) ^ (%%0<64>{3} ^ %%0<64>{7}))));
4: %%4<1> := undef;
5: %%5<1> := (0<64> = %%0<64>);
6: %%6<1> := (%%0<64> <s 0<64>);
7: %%7<1> :=
 (0x8000000000000000 =
  (0x8000000000000000 & (%%1<64> | (! (rdi<64>) & %%0<64>))));
8: rdi<64> := %%0<64>;
9: of<1> := %%7<1>;
10: sf<1> := %%6<1>;
11: zf<1> := %%5<1>;
12: af<1> := %%4<1>;
13: pf<1> := %%3<1>;
14: cf<1> := %%2<1>;
15: goto (0x4000b0, 0) 
  4000b0: 48 01 c7 add %rax,%rdi
0: %%0<64> := (rdi<64> & rax<64>);
1: %%1<64> := (rdi<64> + rax<64>);
2: %%2<64> := ! (%%1<64>);
3: %%3<1> :=
 (0x8000000000000000 =
  (0x8000000000000000 &
   (((rdi<64> | rax<64>) & %%2<64>) | (%%0<64> & %%1<64>))));
4: %%4<1> :=
 !
 ((((%%1<64>{0} ^ %%1<64>{4}) ^ (%%1<64>{2} ^ %%1<64>{6})) ^
   ((%%1<64>{1} ^ %%1<64>{5}) ^ (%%1<64>{3} ^ %%1<64>{7}))));
5: %%5<1> := undef;
6: %%6<1> := (0<64> = %%1<64>);
7: %%7<1> := (%%1<64> <s 0<64>);
8: %%8<1> :=
 (0x8000000000000000 =
  (0x8000000000000000 &
   ((%%0<64> & %%2<64>) | ((! (rdi<64>) & ! (rax<64>)) & %%1<64>))));
9: rdi<64> := %%1<64>;
10: of<1> := %%8<1>;
11: sf<1> := %%7<1>;
12: zf<1> := %%6<1>;
13: af<1> := %%5<1>;
14: pf<1> := %%4<1>;
15: cf<1> := %%3<1>;
16: goto (0x4000b3, 0) 
  4000b3: eb dd jmp 0x400092
0: goto (0x400092, 0) 
  4000b5: c3 ret
0: %%0<64> := (rsp<64> + 8<64>);
1: %%1<64> := @[rsp<64>,<-,8];
2: rsp<64> := %%0<64>;
3: goto %%1<64> #return
  4000b6: 66 90 nop
0: goto (0x4000b8, 0) 
004000b8 <echo_uint64>:
  4000b8: 66 68 00 0a pushw $0xa00
0: %%0<64> := (rsp<64> - 2<64>);
1: @[%%0<64>,<-,2] := 2560<16>;
2: rsp<64> := %%0<64>;
3: goto (0x4000bc, 0) 
  4000bc: 48 89 e6 mov %rsp,%rsi
0: %%0<64> := rsp<64>;
1: rsi<64> := %%0<64>;
2: goto (0x4000bf, 0) 
  4000bf: 66 5a pop %dx
0: %%0<16> := @[rsp<64>,<-,2];
1: %%1<64> := (rsp<64> + 2<64>);
2: rsp<64> := %%1<64>;
3: rdx<64>{0, 15} := %%0<16>;
4: goto (0x4000c1, 0) 
  4000c1: bb 0a 00 00 00 mov $0xa,%ebx
0: rbx<64> := 10<64>;
1: goto (0x4000c6, 0) 
  4000c6: 48 ff ce dec %rsi
0: %%0<64> := (rsi<64> - 1<64>);
1: %%1<1> :=
 !
 ((((%%0<64>{0} ^ %%0<64>{4}) ^ (%%0<64>{2} ^ %%0<64>{6})) ^
   ((%%0<64>{1} ^ %%0<64>{5}) ^ (%%0<64>{3} ^ %%0<64>{7}))));
2: %%2<1> := undef;
3: %%3<1> := (0<64> = %%0<64>);
4: %%4<1> := (%%0<64> <s 0<64>);
5: %%5<1> :=
 (0x8000000000000000 = (0x8000000000000000 & (rsi<64> & ! (%%0<64>))));
6: rsi<64> := %%0<64>;
7: of<1> := %%5<1>;
8: sf<1> := %%4<1>;
9: zf<1> := %%3<1>;
10: af<1> := %%2<1>;
11: pf<1> := %%1<1>;
12: goto (0x4000c9, 0) 
  4000c9: 31 d2 xor %edx,%edx
0: %%0<1> := undef;
1: rdx<64> := 0<64>;
2: of<1> := 0<1>;
3: sf<1> := 0<1>;
4: zf<1> := -1<1>;
5: af<1> := %%0<1>;
6: pf<1> := -1<1>;
7: cf<1> := 0<1>;
8: goto (0x4000cb, 0) 
  4000cb: 48 f7 f3 div %rbx
0: %%0<128> := (uext128 rbx<64>);
1: %%1<1> := (0<64> = rbx<64>);
2: %%2<128> := (rdx<64> :: rax<64>);
3: %%3<64> := %%1<1> ? rax<64> : (%%2<128> /u %%0<128>){63..0};
4: %%4<64> := %%1<1> ? rdx<64> : (%%2<128> %u %%0<128>){63..0};
5: if %%1<1> goto 6 else goto 7
6: @assert (0<1>);
7: rdx<64> := %%4<64>;
8: rax<64> := %%3<64>;
9: goto (0x4000ce, 0) 
  4000ce: 80 c2 30 add $0x30,%dl
0: %%0<8> := rdx<64>{7..0};
1: %%1<8> := (%%0<8> + 48<8>);
2: %%2<1> := (-128<8> = (-128<8> & (%%0<8> & ! (%%1<8>))));
3: %%3<1> :=
 !
 ((((%%1<8>{0} ^ %%1<8>{4}) ^ (%%1<8>{2} ^ %%1<8>{6})) ^
   ((%%1<8>{1} ^ %%1<8>{5}) ^ (%%1<8>{3} ^ %%1<8>{7}))));
4: %%4<1> := undef;
5: %%5<1> := (0<8> = %%1<8>);
6: %%6<1> := (%%1<8> <s 0<8>);
7: %%7<1> := (-128<8> = (-128<8> & (! (%%0<8>) & %%1<8>)));
8: rdx<64>{0, 7} := %%1<8>;
9: of<1> := %%7<1>;
10: sf<1> := %%6<1>;
11: zf<1> := %%5<1>;
12: af<1> := %%4<1>;
13: pf<1> := %%3<1>;
14: cf<1> := %%2<1>;
15: goto (0x4000d1, 0) 
  4000d1: 88 16 mov %dl,(%rsi)
0: %%0<8> := rdx<64>{7..0};
1: %%1<64> := rsi<64>;
2: @[%%1<64>,<-,1] := %%0<8>;
3: goto (0x4000d3, 0) 
  4000d3: 48 85 c0 test %rax,%rax
0: %%0<1> :=
 !
 ((((rax<64>{0} ^ rax<64>{4}) ^ (rax<64>{2} ^ rax<64>{6})) ^
   ((rax<64>{1} ^ rax<64>{5}) ^ (rax<64>{3} ^ rax<64>{7}))));
1: %%1<1> := undef;
2: %%2<1> := (0<64> = rax<64>);
3: %%3<1> := (rax<64> <s 0<64>);
4: of<1> := 0<1>;
5: sf<1> := %%3<1>;
6: zf<1> := %%2<1>;
7: af<1> := %%1<1>;
8: pf<1> := %%0<1>;
9: cf<1> := 0<1>;
10: goto (0x4000d6, 0) 
  4000d6: 75 ee jne 0x4000c6
0: if ! (zf<1>) goto 2 else goto 1
1: goto (0x4000d8, 0) 
2: goto (0x4000c6, 0) 
  4000d8: bf 01 00 00 00 mov $0x1,%edi
0: rdi<64> := 1<64>;
1: goto (0x4000dd, 0) 
  4000dd: 48 89 e2 mov %rsp,%rdx
0: %%0<64> := rsp<64>;
1: rdx<64> := %%0<64>;
2: goto (0x4000e0, 0) 
  4000e0: 48 29 f2 sub %rsi,%rdx
0: %%0<64> := ! (rdx<64>);
1: %%1<64> := (rdx<64> - rsi<64>);
2: %%2<64> := ! (%%1<64>);
3: %%3<64> := (%%0<64> & rsi<64>);
4: %%4<1> :=
 (0x8000000000000000 =
  (0x8000000000000000 &
   (((%%0<64> | rsi<64>) & %%1<64>) | (%%3<64> & %%2<64>))));
5: %%5<1> :=
 !
 ((((%%1<64>{0} ^ %%1<64>{4}) ^ (%%1<64>{2} ^ %%1<64>{6})) ^
   ((%%1<64>{1} ^ %%1<64>{5}) ^ (%%1<64>{3} ^ %%1<64>{7}))));
6: %%6<1> := undef;
7: %%7<1> := (0<64> = %%1<64>);
8: %%8<1> := (%%1<64> <s 0<64>);
9: %%9<1> :=
 (0x8000000000000000 =
  (0x8000000000000000 &
   (((rdx<64> & ! (rsi<64>)) & %%2<64>) | (%%3<64> & %%1<64>))));
10: rdx<64> := %%1<64>;
11: of<1> := %%9<1>;
12: sf<1> := %%8<1>;
13: zf<1> := %%7<1>;
14: af<1> := %%6<1>;
15: pf<1> := %%5<1>;
16: cf<1> := %%4<1>;
17: goto (0x4000e3, 0) 
  4000e3: 89 f8 mov %edi,%eax
0: %%0<64> := (0x00000000ffffffff & rdi<64>);
1: rax<64> := %%0<64>;
2: goto (0x4000e5, 0) 
  4000e5: 0f 05 syscall
0: #unsupported syscall
  4000e7: c3 ret
0: %%0<64> := (rsp<64> + 8<64>);
1: %%1<64> := @[rsp<64>,<-,8];
2: rsp<64> := %%0<64>;
3: goto %%1<64> #return
004000e8 <_start>:
  4000e8: 5f pop %rdi
0: %%0<64> := (rsp<64> + 8<64>);
1: %%1<64> := @[rsp<64>,<-,8];
2: rdi<64> := %%1<64>;
3: rsp<64> := %%0<64>;
4: goto (0x4000e9, 0) 
  4000e9: 66 83 ff 02 cmp $0x2,%di
0: %%0<16> := rdi<64>{15..0};
1: %%1<16> := (%%0<16> - 2<16>);
2: %%2<1> := (0x8000 = (0x8000 & (! (%%0<16>) & %%1<16>)));
3: %%3<1> :=
 !
 ((((%%1<16>{0} ^ %%1<16>{4}) ^ (%%1<16>{2} ^ %%1<16>{6})) ^
   ((%%1<16>{1} ^ %%1<16>{5}) ^ (%%1<16>{3} ^ %%1<16>{7}))));
4: %%4<1> := undef;
5: %%5<1> := (0<16> = %%1<16>);
6: %%6<1> := (%%1<16> <s 0<16>);
7: %%7<1> := (0x8000 = (0x8000 & (%%0<16> & ! (%%1<16>))));
8: of<1> := %%7<1>;
9: sf<1> := %%6<1>;
10: zf<1> := %%5<1>;
11: af<1> := %%4<1>;
12: pf<1> := %%3<1>;
13: cf<1> := %%2<1>;
14: goto (0x4000ed, 0) 
  4000ed: 75 1f jne 0x40010e
0: if ! (zf<1>) goto 2 else goto 1
1: goto (0x4000ef, 0) 
2: goto (0x40010e, 0) 
  4000ef: 48 89 e7 mov %rsp,%rdi
0: %%0<64> := rsp<64>;
1: rdi<64> := %%0<64>;
2: goto (0x4000f2, 0) 
  4000f2: 48 8b 77 08 mov 0x8(%rdi),%rsi
0: %%0<64> := @[(rdi<64> + 8<64>),<-,8];
1: rsi<64> := %%0<64>;
2: goto (0x4000f6, 0) 
  4000f6: e8 95 ff ff ff call 0x400090
0: %%0<64> := (rsp<64> - 8<64>);
1: @[%%0<64>,<-,8] := 0x00000000004000fb;
2: rsp<64> := %%0<64>;
3: goto (0x400090, 0) #call with return address @ (0x4000fb, 0)
  4000fb: e8 78 ff ff ff call 0x400078
0: %%0<64> := (rsp<64> - 8<64>);
1: @[%%0<64>,<-,8] := 0x0000000000400100;
2: rsp<64> := %%0<64>;
3: goto (0x400078, 0) #call with return address @ (0x400100, 0)
  400100: e8 b3 ff ff ff call 0x4000b8
0: %%0<64> := (rsp<64> - 8<64>);
1: @[%%0<64>,<-,8] := 0x0000000000400105;
2: rsp<64> := %%0<64>;
3: goto (0x4000b8, 0) #call with return address @ (0x400105, 0)
  400105: 31 ff xor %edi,%edi
0: %%0<1> := undef;
1: rdi<64> := 0<64>;
2: of<1> := 0<1>;
3: sf<1> := 0<1>;
4: zf<1> := -1<1>;
5: af<1> := %%0<1>;
6: pf<1> := -1<1>;
7: cf<1> := 0<1>;
8: goto (0x400107, 0) 
  400107: b8 3c 00 00 00 mov $0x3c,%eax
0: rax<64> := 60<64>;
1: goto (0x40010c, 0) 
  40010c: 0f 05 syscall
0: #unsupported syscall
  40010e: bf 01 00 00 00 mov $0x1,%edi
0: rdi<64> := 1<64>;
1: goto (0x400113, 0) 
  400113: 48 8d 34 25 29 01 40 00 lea 0x400129,%rsi
0: rsi<64> := 0x0000000000400129;
1: goto (0x40011b, 0) 
  40011b: ba 13 00 00 00 mov $0x13,%edx
0: rdx<64> := 19<64>;
1: goto (0x400120, 0) 
  400120: 89 f8 mov %edi,%eax
0: %%0<64> := (0x00000000ffffffff & rdi<64>);
1: rax<64> := %%0<64>;
2: goto (0x400122, 0) 
  400122: 0f 05 syscall
0: #unsupported syscall
  400124: 40 b7 ff mov $0xff,%dil
0: rdi<64>{0, 7} := -1<8>;
1: goto (0x400127, 0) 
  400127: eb de jmp 0x400107
0: goto (0x400107, 0)

Headers

The headers contain information about the type of the file and the structure of its content.

BINSEC can output basic information about the file using the -describe flag.

Browser
Command-line

binsec -describe fibonacci

Output
[kernel:result]                          
ELF Header:
Class:               ELF64                        
Data:                2's complement, little endian
Type:                EXEC                         
Machine:             x86                        
Entry point address: 0x4000e8                     

Section Headers:
[Nr] Name      Type     Addr             Off    Size   ES Flg Lk Inf Al
[ 0]           NULL     0000000000000000 000000 000000 00      0   0  0
[ 1] .text     PROGBITS 0000000000400078 000078 0000b1 00  AX  0   0  4
[ 2] .rodata   PROGBITS 0000000000400129 000129 000013 00   A  0   0  1
[ 3] .symtab   SYMTAB   0000000000000000 000140 000078 18      4   3  8
[ 4] .strtab   STRTAB   0000000000000000 0001b8 00002b 00      0   0  1
[ 5] .shstrtab STRTAB   0000000000000000 0001e3 000029 00      0   0  1
Key to Flags:
W (write), A (alloc), X (execute), M (merge), S (strings), I (info),
L (link order), G (group), T (TLS), O (extra OS processing required)

Symbol table '.symtab' contains 5 entries:
Num:            Value Size Type   Bind   Section Name        
0: 0000000000000000    0 NOTYPE LOCAL  UND                 
1: 0000000000400090   38 FUNC   LOCAL  .text   parse_uint64
2: 00000000004000b8   48 FUNC   LOCAL  .text   echo_uint64
3: 00000000004000e8    0 NOTYPE GLOBAL .text   _start    
4: 0000000000400078   23 FUNC   GLOBAL .text   fibonacci 

tip

You may get more / prettier information using dedicated tools like readelf or readpe.

ELF header

The ELF header identifies the type of the binary file.

ELF Header:
  Class:               ELF64                        
  Data:                2's complement, little endian
  Type:                EXEC                         
  Machine:             x86
  Entry point address: 0x4000e8                     

Here fibonacci is an executable for the x86-64 architecture. The entrypoint (0x4000e8) will be the first address to be executed when the program is started.

info

The file tool determine the file type by reading this header.

Section header

Sections structure the content of the file and provide the mapping between the file offsets and the process virtual addresses.

Section Headers:
 [Nr] Name      Type     Addr             Off    Size   ES Flg Lk Inf Al
 [ 0]           NULL     0000000000000000 000000 000000 00      0   0  0
 [ 1] .text     PROGBITS 0000000000400078 000078 0000b1 00  AX  0   0  4
 [ 2] .rodata   PROGBITS 0000000000400129 000129 000013 00   A  0   0  1
 [ 3] .symtab   SYMTAB   0000000000000000 000140 000078 18      4   3  8
 [ 4] .strtab   STRTAB   0000000000000000 0001b8 00002b 00      0   0  1
 [ 5] .shstrtab STRTAB   0000000000000000 0001e3 000029 00      0   0  1
Key to Flags:
 W (write), A (alloc), X (execute), M (merge), S (strings), I (info),
 L (link order), G (group), T (TLS), O (extra OS processing required)

Here, the program loads two section in memory (A):

.text gets the executable permission (X), it contains the machine instruction;
.rodata contains read-only data.

note

The other sections are not loaded in memory. Their only purpose is to provide or complement metadata like the symbols (.symtab, .strtab) or section names (.shstrtab). They are optional (see strip), but their absence makes it more opaque for human.

Symbol table

Symbols label some elements of the program. They are often provided by the compilation process from a higher language to identify the program functions or global variables.

Symbol table '.symtab' contains 5 entries:
  Num:            Value Size Type   Bind   Section Name        
0000000000000000    0 NOTYPE LOCAL  UND                 
0000000000400090   38 FUNC   LOCAL  .text   parse_uint64
00000000004000b8   48 FUNC   LOCAL  .text   echo_uint64
00000000004000e8    0 NOTYPE GLOBAL .text   _start
0000000000400078   23 FUNC   GLOBAL .text   fibonacci 

Here, fibonacci identifies the entry point of a function that we will study in the next chapter.

Disassembly

The .text section is full of machine instruction opcode. The disassembly aims to recover the (more) human readable assembly language mnemonic.

BINSEC can output the code disassembly using the -disasm flag.

Browser
Command-line

binsec -disasm -disasm-o-dba fibonacci.dba -disasm-sections .text fibonacci

Output
[disasm:result] Linear disassembly from 0x00400078 to 0x00400128
[disasm:result] 0x00400078 31 c0                                  xor %eax,%eax
                0x0040007a 48 85 ff                               test %rdi,%rdi
                0x0040007d 74 0f                                  je 0x40008e
                0x0040007f ba 01 00 00 00                         mov $0x1,%edx
                0x00400084 48 92                                  xchg %rax,%rdx
                0x00400086 48 01 d0                               add %rdx,%rax
                0x00400089 48 ff cf                               dec %rdi
                0x0040008c 75 f6                                  jne 0x400084
                0x0040008e c3                                     ret
                0x0040008f 90                                     nop
                0x00400090 31 ff                                  xor %edi,%edi
                0x00400092 0f b6 06                               movzbl (%rsi),%eax
                0x00400095 85 c0                                  test %eax,%eax
                0x00400097 74 1c                                  je 0x4000b5
                0x00400099 83 e8 30                               sub $0x30,%eax
                0x0040009c 0f 88 82 00 00 00                      js 0x400124
                0x004000a2 3c 09                                  cmp $0x9,%al
                0x004000a4 77 7e                                  ja 0x400124
                0x004000a6 48 ff c6                               inc %rsi
                0x004000a9 48 8d 3c bf                            lea (%rdi,%rdi,4),%rdi
                0x004000ad 48 01 ff                               add %rdi,%rdi
                0x004000b0 48 01 c7                               add %rax,%rdi
                0x004000b3 eb dd                                  jmp 0x400092
                0x004000b5 c3                                     ret
                0x004000b6 66 90                                  nop
                0x004000b8 66 68 00 0a                            pushw $0xa00
                0x004000bc 48 89 e6                               mov %rsp,%rsi
                0x004000bf 66 5a                                  pop %dx
                0x004000c1 bb 0a 00 00 00                         mov $0xa,%ebx
                0x004000c6 48 ff ce                               dec %rsi
                0x004000c9 31 d2                                  xor %edx,%edx
                0x004000cb 48 f7 f3                               div %rbx
                0x004000ce 80 c2 30                               add $0x30,%dl
                0x004000d1 88 16                                  mov %dl,(%rsi)
                0x004000d3 48 85 c0                               test %rax,%rax
                0x004000d6 75 ee                                  jne 0x4000c6
                0x004000d8 bf 01 00 00 00                         mov $0x1,%edi
                0x004000dd 48 89 e2                               mov %rsp,%rdx
                0x004000e0 48 29 f2                               sub %rsi,%rdx
                0x004000e3 89 f8                                  mov %edi,%eax
                0x004000e5 0f 05                                  syscall
                0x004000e7 c3                                     ret
                0x004000e8 5f                                     pop %rdi
                0x004000e9 66 83 ff 02                            cmp $0x2,%di
                0x004000ed 75 1f                                  jne 0x40010e
                0x004000ef 48 89 e7                               mov %rsp,%rdi
                0x004000f2 48 8b 77 08                            mov 0x8(%rdi),%rsi
                0x004000f6 e8 95 ff ff ff                         call 0x400090
                0x004000fb e8 78 ff ff ff                         call 0x400078
                0x00400100 e8 b3 ff ff ff                         call 0x4000b8
                0x00400105 31 ff                                  xor %edi,%edi
                0x00400107 b8 3c 00 00 00                         mov $0x3c,%eax
                0x0040010c 0f 05                                  syscall
                0x0040010e bf 01 00 00 00                         mov $0x1,%edi
                0x00400113 48 8d 34 25 29 01 40 00                lea 0x400129,%rsi
                0x0040011b ba 13 00 00 00                         mov $0x13,%edx
                0x00400120 89 f8                                  mov %edi,%eax
                0x00400122 0f 05                                  syscall
                0x00400124 40 b7 ff                               mov $0xff,%dil
                0x00400127 eb de                                  jmp 0x400107
                
                ## Unresolved jumps (3)
                  0x0040008e; 0x004000b5; 0x004000e7;

In addition, this command output the DBA intermediate representation of BINSEC in the file fibonacci.dba.

fibonacci.dba
# -- 0x00400078 31 c0                                  xor %eax,%eax
%%0<1> := \undef;
rax<64> := 0<64>;
of<1> := 0<1>;
sf<1> := 0<1>;
zf<1> := -1<1>;
af<1> := %%0<1>;
pf<1> := -1<1>;
cf<1> := 0<1>;
goto (0x0040007a, 0) 


# -- 0x0040007a 48 85 ff                               test %rdi,%rdi
%%0<1> :=
     !
     ((((rdi<64>{0} ^ rdi<64>{4}) ^ (rdi<64>{2} ^ rdi<64>{6})) ^
       ((rdi<64>{1} ^ rdi<64>{5}) ^ (rdi<64>{3} ^ rdi<64>{7}))));
%%1<1> := \undef;
%%2<1> := (0<64> = rdi<64>);
%%3<1> := (rdi<64> <s 0<64>);
of<1> := 0<1>;
sf<1> := %%3<1>;
zf<1> := %%2<1>;
af<1> := %%1<1>;
pf<1> := %%0<1>;
cf<1> := 0<1>;
goto (0x0040007d, 0) 


# -- 0x0040007d 74 0f                                  je 0x40008e
if zf<1> goto 2 else goto 1
goto (0x0040007f, 0) 
goto (0x0040008e, 0) 


# -- 0x0040007f ba 01 00 00 00                         mov $0x1,%edx
rdx<64> := 1<64>;
goto (0x00400084, 0) 


# -- 0x00400084 48 92                                  xchg %rax,%rdx
%%0<64> := rdx<64>;
%%1<64> := rax<64>;
rdx<64> := %%1<64>;
rax<64> := %%0<64>;
goto (0x00400086, 0) 


# -- 0x00400086 48 01 d0                               add %rdx,%rax
%%0<64> := (rax<64> & rdx<64>);
%%1<64> := (rax<64> + rdx<64>);
%%2<64> := ! (%%1<64>);
%%3<1> :=
     (0x8000000000000000 =
      (0x8000000000000000 &
       (((rax<64> | rdx<64>) & %%2<64>) | (%%0<64> & %%1<64>))));
%%4<1> :=
     !
     ((((%%1<64>{0} ^ %%1<64>{4}) ^ (%%1<64>{2} ^ %%1<64>{6})) ^
       ((%%1<64>{1} ^ %%1<64>{5}) ^ (%%1<64>{3} ^ %%1<64>{7}))));
%%5<1> := \undef;
%%6<1> := (0<64> = %%1<64>);
%%7<1> := (%%1<64> <s 0<64>);
%%8<1> :=
     (0x8000000000000000 =
      (0x8000000000000000 &
       ((%%0<64> & %%2<64>) | ((! (rax<64>) & ! (rdx<64>)) & %%1<64>))));
rax<64> := %%1<64>;
of<1> := %%8<1>;
sf<1> := %%7<1>;
zf<1> := %%6<1>;
af<1> := %%5<1>;
pf<1> := %%4<1>;
cf<1> := %%3<1>;
goto (0x00400089, 0) 


# -- 0x00400089 48 ff cf                               dec %rdi
%%0<64> := (rdi<64> - 1<64>);
%%1<1> :=
     !
     ((((%%0<64>{0} ^ %%0<64>{4}) ^ (%%0<64>{2} ^ %%0<64>{6})) ^
       ((%%0<64>{1} ^ %%0<64>{5}) ^ (%%0<64>{3} ^ %%0<64>{7}))));
%%2<1> := \undef;
%%3<1> := (0<64> = %%0<64>);
%%4<1> := (%%0<64> <s 0<64>);
%%5<1> :=
     (0x8000000000000000 = (0x8000000000000000 & (rdi<64> & ! (%%0<64>))));
rdi<64> := %%0<64>;
of<1> := %%5<1>;
sf<1> := %%4<1>;
zf<1> := %%3<1>;
af<1> := %%2<1>;
pf<1> := %%1<1>;
goto (0x0040008c, 0) 


# -- 0x0040008c 75 f6                                  jne 0x400084
if ! (zf<1>) goto 2 else goto 1
goto (0x0040008e, 0) 
goto (0x00400084, 0) 


# -- 0x0040008e c3                                     ret
%%0<64> := (rsp<64> + 8<64>);
%%1<64> := @[rsp<64>,8];
rsp<64> := %%0<64>;
goto %%1<64> #return


# -- 0x0040008f 90                                     nop
goto (0x00400090, 0) 


# -- 0x00400090 31 ff                                  xor %edi,%edi
%%0<1> := \undef;
rdi<64> := 0<64>;
of<1> := 0<1>;
sf<1> := 0<1>;
zf<1> := -1<1>;
af<1> := %%0<1>;
pf<1> := -1<1>;
cf<1> := 0<1>;
goto (0x00400092, 0) 


# -- 0x00400092 0f b6 06                               movzbl (%rsi),%eax
%%0<64> := (extu @[rsi<64>,1] 64);
rax<64> := %%0<64>;
goto (0x00400095, 0) 


# -- 0x00400095 85 c0                                  test %eax,%eax
%%0<32> := rax<64>{0,31};
%%1<1> :=
     !
     ((((rax<64>{0} ^ rax<64>{4}) ^ (rax<64>{2} ^ rax<64>{6})) ^
       ((rax<64>{1} ^ rax<64>{5}) ^ (rax<64>{3} ^ rax<64>{7}))));
%%2<1> := \undef;
%%3<1> := (0<32> = %%0<32>);
%%4<1> := (%%0<32> <s 0<32>);
of<1> := 0<1>;
sf<1> := %%4<1>;
zf<1> := %%3<1>;
af<1> := %%2<1>;
pf<1> := %%1<1>;
cf<1> := 0<1>;
goto (0x00400097, 0) 


# -- 0x00400097 74 1c                                  je 0x4000b5
if zf<1> goto 2 else goto 1
goto (0x00400099, 0) 
goto (0x004000b5, 0) 


# -- 0x00400099 83 e8 30                               sub $0x30,%eax
%%0<32> := rax<64>{0,31};
%%1<32> := (%%0<32> - 48<32>);
%%2<1> := (0x80000000 = (0x80000000 & (! (%%0<32>) & %%1<32>)));
%%3<1> :=
     !
     ((((%%1<32>{0} ^ %%1<32>{4}) ^ (%%1<32>{2} ^ %%1<32>{6})) ^
       ((%%1<32>{1} ^ %%1<32>{5}) ^ (%%1<32>{3} ^ %%1<32>{7}))));
%%4<1> := \undef;
%%5<1> := (0<32> = %%1<32>);
%%6<1> := (%%1<32> <s 0<32>);
%%7<1> := (0x80000000 = (0x80000000 & (%%0<32> & ! (%%1<32>))));
%%8<64> := (extu %%1<32> 64);
rax<64> := %%8<64>;
of<1> := %%7<1>;
sf<1> := %%6<1>;
zf<1> := %%5<1>;
af<1> := %%4<1>;
pf<1> := %%3<1>;
cf<1> := %%2<1>;
goto (0x0040009c, 0) 


# -- 0x0040009c 0f 88 82 00 00 00                      js 0x400124
if sf<1> goto 2 else goto 1
goto (0x004000a2, 0) 
goto (0x00400124, 0) 


# -- 0x004000a2 3c 09                                  cmp $0x9,%al
%%0<8> := rax<64>{0,7};
%%1<8> := (%%0<8> - 9<8>);
%%2<1> := (-128<8> = (-128<8> & (! (%%0<8>) & %%1<8>)));
%%3<1> :=
     !
     ((((%%1<8>{0} ^ %%1<8>{4}) ^ (%%1<8>{2} ^ %%1<8>{6})) ^
       ((%%1<8>{1} ^ %%1<8>{5}) ^ (%%1<8>{3} ^ %%1<8>{7}))));
%%4<1> := \undef;
%%5<1> := (0<8> = %%1<8>);
%%6<1> := (%%1<8> <s 0<8>);
%%7<1> := (-128<8> = (-128<8> & (%%0<8> & ! (%%1<8>))));
of<1> := %%7<1>;
sf<1> := %%6<1>;
zf<1> := %%5<1>;
af<1> := %%4<1>;
pf<1> := %%3<1>;
cf<1> := %%2<1>;
goto (0x004000a4, 0) 


# -- 0x004000a4 77 7e                                  ja 0x400124
if ! ((cf<1> | zf<1>)) goto 2 else goto 1
goto (0x004000a6, 0) 
goto (0x00400124, 0) 


# -- 0x004000a6 48 ff c6                               inc %rsi
%%0<64> := (rsi<64> + 1<64>);
%%1<1> :=
     !
     ((((%%0<64>{0} ^ %%0<64>{4}) ^ (%%0<64>{2} ^ %%0<64>{6})) ^
       ((%%0<64>{1} ^ %%0<64>{5}) ^ (%%0<64>{3} ^ %%0<64>{7}))));
%%2<1> := \undef;
%%3<1> := (0<64> = %%0<64>);
%%4<1> := (%%0<64> <s 0<64>);
%%5<1> :=
     (0x8000000000000000 = (0x8000000000000000 & (! (rsi<64>) & %%0<64>)));
rsi<64> := %%0<64>;
of<1> := %%5<1>;
sf<1> := %%4<1>;
zf<1> := %%3<1>;
af<1> := %%2<1>;
pf<1> := %%1<1>;
goto (0x004000a9, 0) 


# -- 0x004000a9 48 8d 3c bf                            lea (%rdi,%rdi,4),%rdi
%%0<64> := (rdi<64> + (rdi<64> << 2<64>));
rdi<64> := %%0<64>;
goto (0x004000ad, 0) 


# -- 0x004000ad 48 01 ff                               add %rdi,%rdi
%%0<64> := (rdi<64> + rdi<64>);
%%1<64> := (rdi<64> & ! (%%0<64>));
%%2<1> :=
     (0x8000000000000000 =
      (0x8000000000000000 & (%%1<64> | (rdi<64> & %%0<64>))));
%%3<1> :=
     !
     ((((%%0<64>{0} ^ %%0<64>{4}) ^ (%%0<64>{2} ^ %%0<64>{6})) ^
       ((%%0<64>{1} ^ %%0<64>{5}) ^ (%%0<64>{3} ^ %%0<64>{7}))));
%%4<1> := \undef;
%%5<1> := (0<64> = %%0<64>);
%%6<1> := (%%0<64> <s 0<64>);
%%7<1> :=
     (0x8000000000000000 =
      (0x8000000000000000 & (%%1<64> | (! (rdi<64>) & %%0<64>))));
rdi<64> := %%0<64>;
of<1> := %%7<1>;
sf<1> := %%6<1>;
zf<1> := %%5<1>;
af<1> := %%4<1>;
pf<1> := %%3<1>;
cf<1> := %%2<1>;
goto (0x004000b0, 0) 


# -- 0x004000b0 48 01 c7                               add %rax,%rdi
%%0<64> := (rdi<64> & rax<64>);
%%1<64> := (rdi<64> + rax<64>);
%%2<64> := ! (%%1<64>);
%%3<1> :=
     (0x8000000000000000 =
      (0x8000000000000000 &
       (((rdi<64> | rax<64>) & %%2<64>) | (%%0<64> & %%1<64>))));
%%4<1> :=
     !
     ((((%%1<64>{0} ^ %%1<64>{4}) ^ (%%1<64>{2} ^ %%1<64>{6})) ^
       ((%%1<64>{1} ^ %%1<64>{5}) ^ (%%1<64>{3} ^ %%1<64>{7}))));
%%5<1> := \undef;
%%6<1> := (0<64> = %%1<64>);
%%7<1> := (%%1<64> <s 0<64>);
%%8<1> :=
     (0x8000000000000000 =
      (0x8000000000000000 &
       ((%%0<64> & %%2<64>) | ((! (rdi<64>) & ! (rax<64>)) & %%1<64>))));
rdi<64> := %%1<64>;
of<1> := %%8<1>;
sf<1> := %%7<1>;
zf<1> := %%6<1>;
af<1> := %%5<1>;
pf<1> := %%4<1>;
cf<1> := %%3<1>;
goto (0x004000b3, 0) 


# -- 0x004000b3 eb dd                                  jmp 0x400092
goto (0x00400092, 0) 


# -- 0x004000b5 c3                                     ret
%%0<64> := (rsp<64> + 8<64>);
%%1<64> := @[rsp<64>,8];
rsp<64> := %%0<64>;
goto %%1<64> #return


# -- 0x004000b6 66 90                                  nop
goto (0x004000b8, 0) 


# -- 0x004000b8 66 68 00 0a                            pushw $0xa00
%%0<64> := (rsp<64> - 2<64>);
@[%%0<64>,2] := 2560<16>;
rsp<64> := %%0<64>;
goto (0x004000bc, 0) 


# -- 0x004000bc 48 89 e6                               mov %rsp,%rsi
%%0<64> := rsp<64>;
rsi<64> := %%0<64>;
goto (0x004000bf, 0) 


# -- 0x004000bf 66 5a                                  pop %dx
%%0<16> := @[rsp<64>,2];
%%1<64> := (rsp<64> + 2<64>);
rsp<64> := %%1<64>;
rdx<64>{0, 15} := %%0<16>;
goto (0x004000c1, 0) 


# -- 0x004000c1 bb 0a 00 00 00                         mov $0xa,%ebx
rbx<64> := 10<64>;
goto (0x004000c6, 0) 


# -- 0x004000c6 48 ff ce                               dec %rsi
%%0<64> := (rsi<64> - 1<64>);
%%1<1> :=
     !
     ((((%%0<64>{0} ^ %%0<64>{4}) ^ (%%0<64>{2} ^ %%0<64>{6})) ^
       ((%%0<64>{1} ^ %%0<64>{5}) ^ (%%0<64>{3} ^ %%0<64>{7}))));
%%2<1> := \undef;
%%3<1> := (0<64> = %%0<64>);
%%4<1> := (%%0<64> <s 0<64>);
%%5<1> :=
     (0x8000000000000000 = (0x8000000000000000 & (rsi<64> & ! (%%0<64>))));
rsi<64> := %%0<64>;
of<1> := %%5<1>;
sf<1> := %%4<1>;
zf<1> := %%3<1>;
af<1> := %%2<1>;
pf<1> := %%1<1>;
goto (0x004000c9, 0) 


# -- 0x004000c9 31 d2                                  xor %edx,%edx
%%0<1> := \undef;
rdx<64> := 0<64>;
of<1> := 0<1>;
sf<1> := 0<1>;
zf<1> := -1<1>;
af<1> := %%0<1>;
pf<1> := -1<1>;
cf<1> := 0<1>;
goto (0x004000cb, 0) 


# -- 0x004000cb 48 f7 f3                               div %rbx
%%0<128> := (extu rbx<64> 128);
%%1<1> := (0<64> = rbx<64>);
%%2<128> := (rdx<64> :: rax<64>);
%%3<64> := %%1<1> ? rax<64> : (%%2<128> /u %%0<128>){0,63};
%%4<64> := %%1<1> ? rdx<64> : (%%2<128> %u %%0<128>){0,63};
if %%1<1> goto 6 else goto 7
@assert (0<1>);
rdx<64> := %%4<64>;
rax<64> := %%3<64>;
goto (0x004000ce, 0) 


# -- 0x004000ce 80 c2 30                               add $0x30,%dl
%%0<8> := rdx<64>{0,7};
%%1<8> := (%%0<8> + 48<8>);
%%2<1> := (-128<8> = (-128<8> & (%%0<8> & ! (%%1<8>))));
%%3<1> :=
     !
     ((((%%1<8>{0} ^ %%1<8>{4}) ^ (%%1<8>{2} ^ %%1<8>{6})) ^
       ((%%1<8>{1} ^ %%1<8>{5}) ^ (%%1<8>{3} ^ %%1<8>{7}))));
%%4<1> := \undef;
%%5<1> := (0<8> = %%1<8>);
%%6<1> := (%%1<8> <s 0<8>);
%%7<1> := (-128<8> = (-128<8> & (! (%%0<8>) & %%1<8>)));
rdx<64>{0, 7} := %%1<8>;
of<1> := %%7<1>;
sf<1> := %%6<1>;
zf<1> := %%5<1>;
af<1> := %%4<1>;
pf<1> := %%3<1>;
cf<1> := %%2<1>;
goto (0x004000d1, 0) 


# -- 0x004000d1 88 16                                  mov %dl,(%rsi)
%%0<8> := rdx<64>{0,7};
%%1<64> := rsi<64>;
@[%%1<64>,1] := %%0<8>;
goto (0x004000d3, 0) 


# -- 0x004000d3 48 85 c0                               test %rax,%rax
%%0<1> :=
     !
     ((((rax<64>{0} ^ rax<64>{4}) ^ (rax<64>{2} ^ rax<64>{6})) ^
       ((rax<64>{1} ^ rax<64>{5}) ^ (rax<64>{3} ^ rax<64>{7}))));
%%1<1> := \undef;
%%2<1> := (0<64> = rax<64>);
%%3<1> := (rax<64> <s 0<64>);
of<1> := 0<1>;
sf<1> := %%3<1>;
zf<1> := %%2<1>;
af<1> := %%1<1>;
pf<1> := %%0<1>;
cf<1> := 0<1>;
goto (0x004000d6, 0) 


# -- 0x004000d6 75 ee                                  jne 0x4000c6
if ! (zf<1>) goto 2 else goto 1
goto (0x004000d8, 0) 
goto (0x004000c6, 0) 


# -- 0x004000d8 bf 01 00 00 00                         mov $0x1,%edi
rdi<64> := 1<64>;
goto (0x004000dd, 0) 


# -- 0x004000dd 48 89 e2                               mov %rsp,%rdx
%%0<64> := rsp<64>;
rdx<64> := %%0<64>;
goto (0x004000e0, 0) 


# -- 0x004000e0 48 29 f2                               sub %rsi,%rdx
%%0<64> := ! (rdx<64>);
%%1<64> := (rdx<64> - rsi<64>);
%%2<64> := ! (%%1<64>);
%%3<64> := (%%0<64> & rsi<64>);
%%4<1> :=
     (0x8000000000000000 =
      (0x8000000000000000 &
       (((%%0<64> | rsi<64>) & %%1<64>) | (%%3<64> & %%2<64>))));
%%5<1> :=
     !
     ((((%%1<64>{0} ^ %%1<64>{4}) ^ (%%1<64>{2} ^ %%1<64>{6})) ^
       ((%%1<64>{1} ^ %%1<64>{5}) ^ (%%1<64>{3} ^ %%1<64>{7}))));
%%6<1> := \undef;
%%7<1> := (0<64> = %%1<64>);
%%8<1> := (%%1<64> <s 0<64>);
%%9<1> :=
     (0x8000000000000000 =
      (0x8000000000000000 &
       (((rdx<64> & ! (rsi<64>)) & %%2<64>) | (%%3<64> & %%1<64>))));
rdx<64> := %%1<64>;
of<1> := %%9<1>;
sf<1> := %%8<1>;
zf<1> := %%7<1>;
af<1> := %%6<1>;
pf<1> := %%5<1>;
cf<1> := %%4<1>;
goto (0x004000e3, 0) 


# -- 0x004000e3 89 f8                                  mov %edi,%eax
%%0<64> := (0x00000000ffffffff & rdi<64>);
rax<64> := %%0<64>;
goto (0x004000e5, 0) 


# -- 0x004000e5 0f 05                                  syscall
#unsupported syscall


# -- 0x004000e7 c3                                     ret
%%0<64> := (rsp<64> + 8<64>);
%%1<64> := @[rsp<64>,8];
rsp<64> := %%0<64>;
goto %%1<64> #return


# -- 0x004000e8 5f                                     pop %rdi
%%0<64> := (rsp<64> + 8<64>);
%%1<64> := @[rsp<64>,8];
rdi<64> := %%1<64>;
rsp<64> := %%0<64>;
goto (0x004000e9, 0) 


# -- 0x004000e9 66 83 ff 02                            cmp $0x2,%di
%%0<16> := rdi<64>{0,15};
%%1<16> := (%%0<16> - 2<16>);
%%2<1> := (0x8000 = (0x8000 & (! (%%0<16>) & %%1<16>)));
%%3<1> :=
     !
     ((((%%1<16>{0} ^ %%1<16>{4}) ^ (%%1<16>{2} ^ %%1<16>{6})) ^
       ((%%1<16>{1} ^ %%1<16>{5}) ^ (%%1<16>{3} ^ %%1<16>{7}))));
%%4<1> := \undef;
%%5<1> := (0<16> = %%1<16>);
%%6<1> := (%%1<16> <s 0<16>);
%%7<1> := (0x8000 = (0x8000 & (%%0<16> & ! (%%1<16>))));
of<1> := %%7<1>;
sf<1> := %%6<1>;
zf<1> := %%5<1>;
af<1> := %%4<1>;
pf<1> := %%3<1>;
cf<1> := %%2<1>;
goto (0x004000ed, 0) 


# -- 0x004000ed 75 1f                                  jne 0x40010e
if ! (zf<1>) goto 2 else goto 1
goto (0x004000ef, 0) 
goto (0x0040010e, 0) 


# -- 0x004000ef 48 89 e7                               mov %rsp,%rdi
%%0<64> := rsp<64>;
rdi<64> := %%0<64>;
goto (0x004000f2, 0) 


# -- 0x004000f2 48 8b 77 08                            mov 0x8(%rdi),%rsi
%%0<64> := @[(rdi<64> + 8<64>),8];
rsi<64> := %%0<64>;
goto (0x004000f6, 0) 


# -- 0x004000f6 e8 95 ff ff ff                         call 0x400090
%%0<64> := (rsp<64> - 8<64>);
@[%%0<64>,8] := 0x00000000004000fb;
rsp<64> := %%0<64>;
goto (0x00400090, 0) #call with return address @ (0x004000fb, 0)


# -- 0x004000fb e8 78 ff ff ff                         call 0x400078
%%0<64> := (rsp<64> - 8<64>);
@[%%0<64>,8] := 0x0000000000400100;
rsp<64> := %%0<64>;
goto (0x00400078, 0) #call with return address @ (0x00400100, 0)


# -- 0x00400100 e8 b3 ff ff ff                         call 0x4000b8
%%0<64> := (rsp<64> - 8<64>);
@[%%0<64>,8] := 0x0000000000400105;
rsp<64> := %%0<64>;
goto (0x004000b8, 0) #call with return address @ (0x00400105, 0)


# -- 0x00400105 31 ff                                  xor %edi,%edi
%%0<1> := \undef;
rdi<64> := 0<64>;
of<1> := 0<1>;
sf<1> := 0<1>;
zf<1> := -1<1>;
af<1> := %%0<1>;
pf<1> := -1<1>;
cf<1> := 0<1>;
goto (0x00400107, 0) 


# -- 0x00400107 b8 3c 00 00 00                         mov $0x3c,%eax
rax<64> := 60<64>;
goto (0x0040010c, 0) 


# -- 0x0040010c 0f 05                                  syscall
#unsupported syscall


# -- 0x0040010e bf 01 00 00 00                         mov $0x1,%edi
rdi<64> := 1<64>;
goto (0x00400113, 0) 


# -- 0x00400113 48 8d 34 25 29 01 40 00                lea 0x400129,%rsi
rsi<64> := 0x0000000000400129;
goto (0x0040011b, 0) 


# -- 0x0040011b ba 13 00 00 00                         mov $0x13,%edx
rdx<64> := 19<64>;
goto (0x00400120, 0) 


# -- 0x00400120 89 f8                                  mov %edi,%eax
%%0<64> := (0x00000000ffffffff & rdi<64>);
rax<64> := %%0<64>;
goto (0x00400122, 0) 


# -- 0x00400122 0f 05                                  syscall
#unsupported syscall


# -- 0x00400124 40 b7 ff                               mov $0xff,%dil
rdi<64>{0, 7} := -1<8>;
goto (0x00400127, 0) 


# -- 0x00400127 eb de                                  jmp 0x400107
goto (0x00400107, 0) 

tip

You will get better output using objdump or a more powerful GUI disassembler like cutter, Ghidra or IDA.

00400078 <fibonacci>:
400078:	31 c0	xor %eax,%eax `0: %%0<1> := undef;1: rax<64> := 0<64>;2: of<1> := 0<1>;3: sf<1> := 0<1>;4: zf<1> := -1<1>;5: af<1> := %%0<1>;6: pf<1> := -1<1>;7: cf<1> := 0<1>;8: goto (0x40007a, 0)`
40007a:	48 85 ff	test %rdi,%rdi `0: %%0<1> := ! ((((rdi<64>{0} ^ rdi<64>{4}) ^ (rdi<64>{2} ^ rdi<64>{6})) ^ ((rdi<64>{1} ^ rdi<64>{5}) ^ (rdi<64>{3} ^ rdi<64>{7}))));1: %%1<1> := undef;2: %%2<1> := (0<64> = rdi<64>);3: %%3<1> := (rdi<64> <s 0<64>);4: of<1> := 0<1>;5: sf<1> := %%3<1>;6: zf<1> := %%2<1>;7: af<1> := %%1<1>;8: pf<1> := %%0<1>;9: cf<1> := 0<1>;10: goto (0x40007d, 0)`
40007d:	74 0f	je 0x40008e `0: if zf<1> goto 2 else goto 11: goto (0x40007f, 0)2: goto (0x40008e, 0)`
40007f:	ba 01 00 00 00	mov $0x1,%edx `0: rdx<64> := 1<64>;1: goto (0x400084, 0)`
400084:	48 92	xchg %rax,%rdx `0: %%0<64> := rdx<64>;1: %%1<64> := rax<64>;2: rdx<64> := %%1<64>;3: rax<64> := %%0<64>;4: goto (0x400086, 0)`
400086:	48 01 d0	add %rdx,%rax `0: %%0<64> := (rax<64> & rdx<64>);1: %%1<64> := (rax<64> + rdx<64>);2: %%2<64> := ! (%%1<64>);3: %%3<1> := (0x8000000000000000 = (0x8000000000000000 & (((rax<64> \| rdx<64>) & %%2<64>) \| (%%0<64> & %%1<64>))));4: %%4<1> := ! ((((%%1<64>{0} ^ %%1<64>{4}) ^ (%%1<64>{2} ^ %%1<64>{6})) ^ ((%%1<64>{1} ^ %%1<64>{5}) ^ (%%1<64>{3} ^ %%1<64>{7}))));5: %%5<1> := undef;6: %%6<1> := (0<64> = %%1<64>);7: %%7<1> := (%%1<64> <s 0<64>);8: %%8<1> := (0x8000000000000000 = (0x8000000000000000 & ((%%0<64> & %%2<64>) \| ((! (rax<64>) & ! (rdx<64>)) & %%1<64>))));9: rax<64> := %%1<64>;10: of<1> := %%8<1>;11: sf<1> := %%7<1>;12: zf<1> := %%6<1>;13: af<1> := %%5<1>;14: pf<1> := %%4<1>;15: cf<1> := %%3<1>;16: goto (0x400089, 0)`
400089:	48 ff cf	dec %rdi `0: %%0<64> := (rdi<64> - 1<64>);1: %%1<1> := ! ((((%%0<64>{0} ^ %%0<64>{4}) ^ (%%0<64>{2} ^ %%0<64>{6})) ^ ((%%0<64>{1} ^ %%0<64>{5}) ^ (%%0<64>{3} ^ %%0<64>{7}))));2: %%2<1> := undef;3: %%3<1> := (0<64> = %%0<64>);4: %%4<1> := (%%0<64> <s 0<64>);5: %%5<1> := (0x8000000000000000 = (0x8000000000000000 & (rdi<64> & ! (%%0<64>))));6: rdi<64> := %%0<64>;7: of<1> := %%5<1>;8: sf<1> := %%4<1>;9: zf<1> := %%3<1>;10: af<1> := %%2<1>;11: pf<1> := %%1<1>;12: goto (0x40008c, 0)`
40008c:	75 f6	jne 0x400084 `0: if ! (zf<1>) goto 2 else goto 11: goto (0x40008e, 0)2: goto (0x400084, 0)`
40008e:	c3	ret `0: %%0<64> := (rsp<64> + 8<64>);1: %%1<64> := @[rsp<64>,<-,8];2: rsp<64> := %%0<64>;3: goto %%1<64> #return`
40008f:	90	nop `0: goto (0x400090, 0)`
00400090 <parse_uint64>:
400090:	31 ff	xor %edi,%edi `0: %%0<1> := undef;1: rdi<64> := 0<64>;2: of<1> := 0<1>;3: sf<1> := 0<1>;4: zf<1> := -1<1>;5: af<1> := %%0<1>;6: pf<1> := -1<1>;7: cf<1> := 0<1>;8: goto (0x400092, 0)`
400092:	0f b6 06	movzbl (%rsi),%eax `0: %%0<64> := (uext64 @[rsi<64>,<-,1]);1: rax<64> := %%0<64>;2: goto (0x400095, 0)`
400095:	85 c0	test %eax,%eax `0: %%0<32> := rax<64>{31..0};1: %%1<1> := ! ((((rax<64>{0} ^ rax<64>{4}) ^ (rax<64>{2} ^ rax<64>{6})) ^ ((rax<64>{1} ^ rax<64>{5}) ^ (rax<64>{3} ^ rax<64>{7}))));2: %%2<1> := undef;3: %%3<1> := (0<32> = %%0<32>);4: %%4<1> := (%%0<32> <s 0<32>);5: of<1> := 0<1>;6: sf<1> := %%4<1>;7: zf<1> := %%3<1>;8: af<1> := %%2<1>;9: pf<1> := %%1<1>;10: cf<1> := 0<1>;11: goto (0x400097, 0)`
400097:	74 1c	je 0x4000b5 `0: if zf<1> goto 2 else goto 11: goto (0x400099, 0)2: goto (0x4000b5, 0)`
400099:	83 e8 30	sub $0x30,%eax `0: %%0<32> := rax<64>{31..0};1: %%1<32> := (%%0<32> - 48<32>);2: %%2<1> := (0x80000000 = (0x80000000 & (! (%%0<32>) & %%1<32>)));3: %%3<1> := ! ((((%%1<32>{0} ^ %%1<32>{4}) ^ (%%1<32>{2} ^ %%1<32>{6})) ^ ((%%1<32>{1} ^ %%1<32>{5}) ^ (%%1<32>{3} ^ %%1<32>{7}))));4: %%4<1> := undef;5: %%5<1> := (0<32> = %%1<32>);6: %%6<1> := (%%1<32> <s 0<32>);7: %%7<1> := (0x80000000 = (0x80000000 & (%%0<32> & ! (%%1<32>))));8: %%8<64> := (uext64 %%1<32>);9: rax<64> := %%8<64>;10: of<1> := %%7<1>;11: sf<1> := %%6<1>;12: zf<1> := %%5<1>;13: af<1> := %%4<1>;14: pf<1> := %%3<1>;15: cf<1> := %%2<1>;16: goto (0x40009c, 0)`
40009c:	0f 88 82 00 00 00	js 0x400124 `0: if sf<1> goto 2 else goto 11: goto (0x4000a2, 0)2: goto (0x400124, 0)`
4000a2:	3c 09	cmp $0x9,%al `0: %%0<8> := rax<64>{7..0};1: %%1<8> := (%%0<8> - 9<8>);2: %%2<1> := (-128<8> = (-128<8> & (! (%%0<8>) & %%1<8>)));3: %%3<1> := ! ((((%%1<8>{0} ^ %%1<8>{4}) ^ (%%1<8>{2} ^ %%1<8>{6})) ^ ((%%1<8>{1} ^ %%1<8>{5}) ^ (%%1<8>{3} ^ %%1<8>{7}))));4: %%4<1> := undef;5: %%5<1> := (0<8> = %%1<8>);6: %%6<1> := (%%1<8> <s 0<8>);7: %%7<1> := (-128<8> = (-128<8> & (%%0<8> & ! (%%1<8>))));8: of<1> := %%7<1>;9: sf<1> := %%6<1>;10: zf<1> := %%5<1>;11: af<1> := %%4<1>;12: pf<1> := %%3<1>;13: cf<1> := %%2<1>;14: goto (0x4000a4, 0)`
4000a4:	77 7e	ja 0x400124 `0: if ! ((cf<1> \| zf<1>)) goto 2 else goto 11: goto (0x4000a6, 0)2: goto (0x400124, 0)`
4000a6:	48 ff c6	inc %rsi `0: %%0<64> := (rsi<64> + 1<64>);1: %%1<1> := ! ((((%%0<64>{0} ^ %%0<64>{4}) ^ (%%0<64>{2} ^ %%0<64>{6})) ^ ((%%0<64>{1} ^ %%0<64>{5}) ^ (%%0<64>{3} ^ %%0<64>{7}))));2: %%2<1> := undef;3: %%3<1> := (0<64> = %%0<64>);4: %%4<1> := (%%0<64> <s 0<64>);5: %%5<1> := (0x8000000000000000 = (0x8000000000000000 & (! (rsi<64>) & %%0<64>)));6: rsi<64> := %%0<64>;7: of<1> := %%5<1>;8: sf<1> := %%4<1>;9: zf<1> := %%3<1>;10: af<1> := %%2<1>;11: pf<1> := %%1<1>;12: goto (0x4000a9, 0)`
4000a9:	48 8d 3c bf	lea (%rdi,%rdi,4),%rdi `0: %%0<64> := (rdi<64> + (rdi<64> lsl 2<64>));1: rdi<64> := %%0<64>;2: goto (0x4000ad, 0)`
4000ad:	48 01 ff	add %rdi,%rdi `0: %%0<64> := (rdi<64> + rdi<64>);1: %%1<64> := (rdi<64> & ! (%%0<64>));2: %%2<1> := (0x8000000000000000 = (0x8000000000000000 & (%%1<64> \| (rdi<64> & %%0<64>))));3: %%3<1> := ! ((((%%0<64>{0} ^ %%0<64>{4}) ^ (%%0<64>{2} ^ %%0<64>{6})) ^ ((%%0<64>{1} ^ %%0<64>{5}) ^ (%%0<64>{3} ^ %%0<64>{7}))));4: %%4<1> := undef;5: %%5<1> := (0<64> = %%0<64>);6: %%6<1> := (%%0<64> <s 0<64>);7: %%7<1> := (0x8000000000000000 = (0x8000000000000000 & (%%1<64> \| (! (rdi<64>) & %%0<64>))));8: rdi<64> := %%0<64>;9: of<1> := %%7<1>;10: sf<1> := %%6<1>;11: zf<1> := %%5<1>;12: af<1> := %%4<1>;13: pf<1> := %%3<1>;14: cf<1> := %%2<1>;15: goto (0x4000b0, 0)`
4000b0:	48 01 c7	add %rax,%rdi `0: %%0<64> := (rdi<64> & rax<64>);1: %%1<64> := (rdi<64> + rax<64>);2: %%2<64> := ! (%%1<64>);3: %%3<1> := (0x8000000000000000 = (0x8000000000000000 & (((rdi<64> \| rax<64>) & %%2<64>) \| (%%0<64> & %%1<64>))));4: %%4<1> := ! ((((%%1<64>{0} ^ %%1<64>{4}) ^ (%%1<64>{2} ^ %%1<64>{6})) ^ ((%%1<64>{1} ^ %%1<64>{5}) ^ (%%1<64>{3} ^ %%1<64>{7}))));5: %%5<1> := undef;6: %%6<1> := (0<64> = %%1<64>);7: %%7<1> := (%%1<64> <s 0<64>);8: %%8<1> := (0x8000000000000000 = (0x8000000000000000 & ((%%0<64> & %%2<64>) \| ((! (rdi<64>) & ! (rax<64>)) & %%1<64>))));9: rdi<64> := %%1<64>;10: of<1> := %%8<1>;11: sf<1> := %%7<1>;12: zf<1> := %%6<1>;13: af<1> := %%5<1>;14: pf<1> := %%4<1>;15: cf<1> := %%3<1>;16: goto (0x4000b3, 0)`
4000b3:	eb dd	jmp 0x400092 `0: goto (0x400092, 0)`
4000b5:	c3	ret `0: %%0<64> := (rsp<64> + 8<64>);1: %%1<64> := @[rsp<64>,<-,8];2: rsp<64> := %%0<64>;3: goto %%1<64> #return`
4000b6:	66 90	nop `0: goto (0x4000b8, 0)`
004000b8 <echo_uint64>:
4000b8:	66 68 00 0a	pushw $0xa00 `0: %%0<64> := (rsp<64> - 2<64>);1: @[%%0<64>,<-,2] := 2560<16>;2: rsp<64> := %%0<64>;3: goto (0x4000bc, 0)`
4000bc:	48 89 e6	mov %rsp,%rsi `0: %%0<64> := rsp<64>;1: rsi<64> := %%0<64>;2: goto (0x4000bf, 0)`
4000bf:	66 5a	pop %dx `0: %%0<16> := @[rsp<64>,<-,2];1: %%1<64> := (rsp<64> + 2<64>);2: rsp<64> := %%1<64>;3: rdx<64>{0, 15} := %%0<16>;4: goto (0x4000c1, 0)`
4000c1:	bb 0a 00 00 00	mov $0xa,%ebx `0: rbx<64> := 10<64>;1: goto (0x4000c6, 0)`
4000c6:	48 ff ce	dec %rsi `0: %%0<64> := (rsi<64> - 1<64>);1: %%1<1> := ! ((((%%0<64>{0} ^ %%0<64>{4}) ^ (%%0<64>{2} ^ %%0<64>{6})) ^ ((%%0<64>{1} ^ %%0<64>{5}) ^ (%%0<64>{3} ^ %%0<64>{7}))));2: %%2<1> := undef;3: %%3<1> := (0<64> = %%0<64>);4: %%4<1> := (%%0<64> <s 0<64>);5: %%5<1> := (0x8000000000000000 = (0x8000000000000000 & (rsi<64> & ! (%%0<64>))));6: rsi<64> := %%0<64>;7: of<1> := %%5<1>;8: sf<1> := %%4<1>;9: zf<1> := %%3<1>;10: af<1> := %%2<1>;11: pf<1> := %%1<1>;12: goto (0x4000c9, 0)`
4000c9:	31 d2	xor %edx,%edx `0: %%0<1> := undef;1: rdx<64> := 0<64>;2: of<1> := 0<1>;3: sf<1> := 0<1>;4: zf<1> := -1<1>;5: af<1> := %%0<1>;6: pf<1> := -1<1>;7: cf<1> := 0<1>;8: goto (0x4000cb, 0)`
4000cb:	48 f7 f3	div %rbx `0: %%0<128> := (uext128 rbx<64>);1: %%1<1> := (0<64> = rbx<64>);2: %%2<128> := (rdx<64> :: rax<64>);3: %%3<64> := %%1<1> ? rax<64> : (%%2<128> /u %%0<128>){63..0};4: %%4<64> := %%1<1> ? rdx<64> : (%%2<128> %u %%0<128>){63..0};5: if %%1<1> goto 6 else goto 76: @assert (0<1>);7: rdx<64> := %%4<64>;8: rax<64> := %%3<64>;9: goto (0x4000ce, 0)`
4000ce:	80 c2 30	add $0x30,%dl `0: %%0<8> := rdx<64>{7..0};1: %%1<8> := (%%0<8> + 48<8>);2: %%2<1> := (-128<8> = (-128<8> & (%%0<8> & ! (%%1<8>))));3: %%3<1> := ! ((((%%1<8>{0} ^ %%1<8>{4}) ^ (%%1<8>{2} ^ %%1<8>{6})) ^ ((%%1<8>{1} ^ %%1<8>{5}) ^ (%%1<8>{3} ^ %%1<8>{7}))));4: %%4<1> := undef;5: %%5<1> := (0<8> = %%1<8>);6: %%6<1> := (%%1<8> <s 0<8>);7: %%7<1> := (-128<8> = (-128<8> & (! (%%0<8>) & %%1<8>)));8: rdx<64>{0, 7} := %%1<8>;9: of<1> := %%7<1>;10: sf<1> := %%6<1>;11: zf<1> := %%5<1>;12: af<1> := %%4<1>;13: pf<1> := %%3<1>;14: cf<1> := %%2<1>;15: goto (0x4000d1, 0)`
4000d1:	88 16	mov %dl,(%rsi) `0: %%0<8> := rdx<64>{7..0};1: %%1<64> := rsi<64>;2: @[%%1<64>,<-,1] := %%0<8>;3: goto (0x4000d3, 0)`
4000d3:	48 85 c0	test %rax,%rax `0: %%0<1> := ! ((((rax<64>{0} ^ rax<64>{4}) ^ (rax<64>{2} ^ rax<64>{6})) ^ ((rax<64>{1} ^ rax<64>{5}) ^ (rax<64>{3} ^ rax<64>{7}))));1: %%1<1> := undef;2: %%2<1> := (0<64> = rax<64>);3: %%3<1> := (rax<64> <s 0<64>);4: of<1> := 0<1>;5: sf<1> := %%3<1>;6: zf<1> := %%2<1>;7: af<1> := %%1<1>;8: pf<1> := %%0<1>;9: cf<1> := 0<1>;10: goto (0x4000d6, 0)`
4000d6:	75 ee	jne 0x4000c6 `0: if ! (zf<1>) goto 2 else goto 11: goto (0x4000d8, 0)2: goto (0x4000c6, 0)`
4000d8:	bf 01 00 00 00	mov $0x1,%edi `0: rdi<64> := 1<64>;1: goto (0x4000dd, 0)`
4000dd:	48 89 e2	mov %rsp,%rdx `0: %%0<64> := rsp<64>;1: rdx<64> := %%0<64>;2: goto (0x4000e0, 0)`
4000e0:	48 29 f2	sub %rsi,%rdx `0: %%0<64> := ! (rdx<64>);1: %%1<64> := (rdx<64> - rsi<64>);2: %%2<64> := ! (%%1<64>);3: %%3<64> := (%%0<64> & rsi<64>);4: %%4<1> := (0x8000000000000000 = (0x8000000000000000 & (((%%0<64> \| rsi<64>) & %%1<64>) \| (%%3<64> & %%2<64>))));5: %%5<1> := ! ((((%%1<64>{0} ^ %%1<64>{4}) ^ (%%1<64>{2} ^ %%1<64>{6})) ^ ((%%1<64>{1} ^ %%1<64>{5}) ^ (%%1<64>{3} ^ %%1<64>{7}))));6: %%6<1> := undef;7: %%7<1> := (0<64> = %%1<64>);8: %%8<1> := (%%1<64> <s 0<64>);9: %%9<1> := (0x8000000000000000 = (0x8000000000000000 & (((rdx<64> & ! (rsi<64>)) & %%2<64>) \| (%%3<64> & %%1<64>))));10: rdx<64> := %%1<64>;11: of<1> := %%9<1>;12: sf<1> := %%8<1>;13: zf<1> := %%7<1>;14: af<1> := %%6<1>;15: pf<1> := %%5<1>;16: cf<1> := %%4<1>;17: goto (0x4000e3, 0)`
4000e3:	89 f8	mov %edi,%eax `0: %%0<64> := (0x00000000ffffffff & rdi<64>);1: rax<64> := %%0<64>;2: goto (0x4000e5, 0)`
4000e5:	0f 05	syscall `0: #unsupported syscall`
4000e7:	c3	ret `0: %%0<64> := (rsp<64> + 8<64>);1: %%1<64> := @[rsp<64>,<-,8];2: rsp<64> := %%0<64>;3: goto %%1<64> #return`
004000e8 <_start>:
4000e8:	5f	pop %rdi `0: %%0<64> := (rsp<64> + 8<64>);1: %%1<64> := @[rsp<64>,<-,8];2: rdi<64> := %%1<64>;3: rsp<64> := %%0<64>;4: goto (0x4000e9, 0)`
4000e9:	66 83 ff 02	cmp $0x2,%di `0: %%0<16> := rdi<64>{15..0};1: %%1<16> := (%%0<16> - 2<16>);2: %%2<1> := (0x8000 = (0x8000 & (! (%%0<16>) & %%1<16>)));3: %%3<1> := ! ((((%%1<16>{0} ^ %%1<16>{4}) ^ (%%1<16>{2} ^ %%1<16>{6})) ^ ((%%1<16>{1} ^ %%1<16>{5}) ^ (%%1<16>{3} ^ %%1<16>{7}))));4: %%4<1> := undef;5: %%5<1> := (0<16> = %%1<16>);6: %%6<1> := (%%1<16> <s 0<16>);7: %%7<1> := (0x8000 = (0x8000 & (%%0<16> & ! (%%1<16>))));8: of<1> := %%7<1>;9: sf<1> := %%6<1>;10: zf<1> := %%5<1>;11: af<1> := %%4<1>;12: pf<1> := %%3<1>;13: cf<1> := %%2<1>;14: goto (0x4000ed, 0)`
4000ed:	75 1f	jne 0x40010e `0: if ! (zf<1>) goto 2 else goto 11: goto (0x4000ef, 0)2: goto (0x40010e, 0)`
4000ef:	48 89 e7	mov %rsp,%rdi `0: %%0<64> := rsp<64>;1: rdi<64> := %%0<64>;2: goto (0x4000f2, 0)`
4000f2:	48 8b 77 08	mov 0x8(%rdi),%rsi `0: %%0<64> := @[(rdi<64> + 8<64>),<-,8];1: rsi<64> := %%0<64>;2: goto (0x4000f6, 0)`
4000f6:	e8 95 ff ff ff	call 0x400090 `0: %%0<64> := (rsp<64> - 8<64>);1: @[%%0<64>,<-,8] := 0x00000000004000fb;2: rsp<64> := %%0<64>;3: goto (0x400090, 0) #call with return address @ (0x4000fb, 0)`
4000fb:	e8 78 ff ff ff	call 0x400078 `0: %%0<64> := (rsp<64> - 8<64>);1: @[%%0<64>,<-,8] := 0x0000000000400100;2: rsp<64> := %%0<64>;3: goto (0x400078, 0) #call with return address @ (0x400100, 0)`
400100:	e8 b3 ff ff ff	call 0x4000b8 `0: %%0<64> := (rsp<64> - 8<64>);1: @[%%0<64>,<-,8] := 0x0000000000400105;2: rsp<64> := %%0<64>;3: goto (0x4000b8, 0) #call with return address @ (0x400105, 0)`
400105:	31 ff	xor %edi,%edi `0: %%0<1> := undef;1: rdi<64> := 0<64>;2: of<1> := 0<1>;3: sf<1> := 0<1>;4: zf<1> := -1<1>;5: af<1> := %%0<1>;6: pf<1> := -1<1>;7: cf<1> := 0<1>;8: goto (0x400107, 0)`
400107:	b8 3c 00 00 00	mov $0x3c,%eax `0: rax<64> := 60<64>;1: goto (0x40010c, 0)`
40010c:	0f 05	syscall `0: #unsupported syscall`
40010e:	bf 01 00 00 00	mov $0x1,%edi `0: rdi<64> := 1<64>;1: goto (0x400113, 0)`
400113:	48 8d 34 25 29 01 40 00	lea 0x400129,%rsi `0: rsi<64> := 0x0000000000400129;1: goto (0x40011b, 0)`
40011b:	ba 13 00 00 00	mov $0x13,%edx `0: rdx<64> := 19<64>;1: goto (0x400120, 0)`
400120:	89 f8	mov %edi,%eax `0: %%0<64> := (0x00000000ffffffff & rdi<64>);1: rax<64> := %%0<64>;2: goto (0x400122, 0)`
400122:	0f 05	syscall `0: #unsupported syscall`
400124:	40 b7 ff	mov $0xff,%dil `0: rdi<64>{0, 7} := -1<8>;1: goto (0x400127, 0)`
400127:	eb de	jmp 0x400107 `0: goto (0x400107, 0)`

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