请考虑下面的代码段。
程序的入口点是C源代码中定义的main。现在，通常函数从减少%rsp开始为局部变量保留空间。但是在这里，GCC编译器在一些增加的（初始）函数中保留了这个空间。
我的问题是，在这些GCC特定的初始化函数中，我在哪里查找保留变量的字节数？在这种情况下，保留字节数为0x08。
此外，这些初始函数的调用顺序是什么？
00000000004003c0 <_start>:
4003c0: 31 ed xor ebp,ebp
4003c2: 49 89 d1 mov r9,rdx
4003c5: 5e pop rsi
4003c6: 48 89 e2 mov rdx,rsp
4003c9: 48 83 e4 f0 and rsp,0xfffffffffffffff0
4003cd: 50 push rax
4003ce: 54 push rsp
4003cf: 49 c7 c0 a0 05 40 00 mov r8,0x4005a0
4003d6: 48 c7 c1 30 05 40 00 mov rcx,0x400530
4003dd: 48 c7 c7 c0 04 40 00 mov rdi,0x4004c0
4003e4: e8 b7 ff ff ff call 4003a0 <__libc_start_main@plt>
4003e9: f4 hlt
4003ea: 66 0f 1f 44 00 00 nop WORD PTR [rax+rax*1+0x0]
00000000004003f0 <deregister_tm_clones>:
4003f0: b8 37 10 60 00 mov eax,0x601037
4003f5: 55 push rbp
4003f6: 48 2d 30 10 60 00 sub rax,0x601030
4003fc: 48 83 f8 0e cmp rax,0xe
400400: 48 89 e5 mov rbp,rsp
400403: 76 1b jbe 400420 <deregister_tm_clones+0x30>
400405: b8 00 00 00 00 mov eax,0x0
40040a: 48 85 c0 test rax,rax
40040d: 74 11 je 400420 <deregister_tm_clones+0x30>
40040f: 5d pop rbp
400410: bf 30 10 60 00 mov edi,0x601030
400415: ff e0 jmp rax
400417: 66 0f 1f 84 00 00 00 nop WORD PTR [rax+rax*1+0x0]
40041e: 00 00
400420: 5d pop rbp
400421: c3 ret
400422: 0f 1f 40 00 nop DWORD PTR [rax+0x0]
400426: 66 2e 0f 1f 84 00 00 nop WORD PTR cs:[rax+rax*1+0x0]
40042d: 00 00 00
0000000000400430 <register_tm_clones>:
400430: be 30 10 60 00 mov esi,0x601030
400435: 55 push rbp
400436: 48 81 ee 30 10 60 00 sub rsi,0x601030
40043d: 48 c1 fe 03 sar rsi,0x3
400441: 48 89 e5 mov rbp,rsp
400444: 48 89 f0 mov rax,rsi
400447: 48 c1 e8 3f shr rax,0x3f
40044b: 48 01 c6 add rsi,rax
40044e: 48 d1 fe sar rsi,1
400451: 74 15 je 400468 <register_tm_clones+0x38>
400453: b8 00 00 00 00 mov eax,0x0
400458: 48 85 c0 test rax,rax
40045b: 74 0b je 400468 <register_tm_clones+0x38>
40045d: 5d pop rbp
40045e: bf 30 10 60 00 mov edi,0x601030
400463: ff e0 jmp rax
400465: 0f 1f 00 nop DWORD PTR [rax]
400468: 5d pop rbp
400469: c3 ret
40046a: 66 0f 1f 44 00 00 nop WORD PTR [rax+rax*1+0x0]
0000000000400470 <__do_global_dtors_aux>:
400470: 80 3d b9 0b 20 00 00 cmp BYTE PTR [rip+0x200bb9],0x0 # 601030 <__TMC_END__>
400477: 75 11 jne 40048a <__do_global_dtors_aux+0x1a>
400479: 55 push rbp
40047a: 48 89 e5 mov rbp,rsp
40047d: e8 6e ff ff ff call 4003f0 <deregister_tm_clones>
400482: 5d pop rbp
400483: c6 05 a6 0b 20 00 01 mov BYTE PTR [rip+0x200ba6],0x1 # 601030 <__TMC_END__>
40048a: f3 c3 repz ret
40048c: 0f 1f 40 00 nop DWORD PTR [rax+0x0]
0000000000400490 <frame_dummy>:
400490: bf 20 0e 60 00 mov edi,0x600e20
400495: 48 83 3f 00 cmp QWORD PTR [rdi],0x0
400499: 75 05 jne 4004a0 <frame_dummy+0x10>
40049b: eb 93 jmp 400430 <register_tm_clones>
40049d: 0f 1f 00 nop DWORD PTR [rax]
4004a0: b8 00 00 00 00 mov eax,0x0
4004a5: 48 85 c0 test rax,rax
4004a8: 74 f1 je 40049b <frame_dummy+0xb>
4004aa: 55 push rbp
4004ab: 48 89 e5 mov rbp,rsp
4004ae: ff d0 call rax
4004b0: 5d pop rbp
4004b1: e9 7a ff ff ff jmp 400430 <register_tm_clones>
4004b6: 66 2e 0f 1f 84 00 00 nop WORD PTR cs:[rax+rax*1+0x0]
4004bd: 00 00 00
00000000004004c0 <main>:
4004c0: 55 push rbp
4004c1: 48 89 e5 mov rbp,rsp
4004c4: c7 45 f8 00 00 00 00 mov DWORD PTR [rbp-0x8],0x0
4004cb: c7 45 fc 01 00 00 00 mov DWORD PTR [rbp-0x4],0x1
4004d2: eb 46 jmp 40051a <.cend>
4004d4: 66 66 66 2e 0f 1f 84 data16 data16 nop WORD PTR cs:[rax+rax*1+0x0]
4004db: 00 00 00 00 00
4004e0: ff 05 4e 0b 20 00 inc DWORD PTR [rip+0x200b4e] # 601034 <sum>
4004e6: 50 push rax
4004e7: 53 push rbx
4004e8: 56 push rsi
4004e9: 48 31 c0 xor rax,rax
4004ec: 48 c7 c6 14 05 40 00 mov rsi,0x400514
00000000004004f3 <.cloop>:
4004f3: 48 0f b6 1e movzx rbx,BYTE PTR [rsi]
4004f7: 48 31 d8 xor rax,rbx
4004fa: 48 ff c6 inc rsi
4004fd: 48 81 fe 1a 05 40 00 cmp rsi,0x40051a
400504: 75 ed jne 4004f3 <.cloop>
400506: 48 83 f8 00 cmp rax,0x0
40050a: 74 05 je 400511 <.restore>
40050c: 48 31 c0 xor rax,rax
40050f: ff d0 call rax
0000000000400511 <.restore>:
400511: 5e pop rsi
400512: 5b pop rbx
400513: 58 pop rax
0000000000400514 <.cstart>:
400514: eb 01 jmp 400517 <.end>
0000000000400516 <.cslot>:
400516: ac lods al,BYTE PTR ds:[rsi]
0000000000400517 <.end>:
400517: ff 45 fc inc DWORD PTR [rbp-0x4]
000000000040051a <.cend>:
40051a: 83 7d fc 1e cmp DWORD PTR [rbp-0x4],0x1e
40051e: 7e c0 jle 4004e0 <main+0x20>
400520: 8b 05 0e 0b 20 00 mov eax,DWORD PTR [rip+0x200b0e] # 601034 <sum>
400526: 5d pop rbp
400527: c3 ret
400528: 0f 1f 84 00 00 00 00 nop DWORD PTR [rax+rax*1+0x0]
40052f: 00
0000000000400530 <__libc_csu_init>:
400530: 41 57 push r15
400532: 41 56 push r14
400534: 41 89 ff mov r15d,edi
400537: 41 55 push r13
400539: 41 54 push r12
40053b: 4c 8d 25 ce 08 20 00 lea r12,[rip+0x2008ce] # 600e10 <__frame_dummy_init_array_entry>
400542: 55 push rbp
400543: 48 8d 2d ce 08 20 00 lea rbp,[rip+0x2008ce] # 600e18 <__init_array_end>
40054a: 53 push rbx
40054b: 49 89 f6 mov r14,rsi
40054e: 49 89 d5 mov r13,rdx
400551: 4c 29 e5 sub rbp,r12
400554: 48 83 ec 08 sub rsp,0x8
400558: 48 c1 fd 03 sar rbp,0x3
40055c: e8 0f fe ff ff call 400370 <_init>
400561: 48 85 ed test rbp,rbp
400564: 74 20 je 400586 <__libc_csu_init+0x56>
400566: 31 db xor ebx,ebx
400568: 0f 1f 84 00 00 00 00 nop DWORD PTR [rax+rax*1+0x0]
40056f: 00
400570: 4c 89 ea mov rdx,r13
400573: 4c 89 f6 mov rsi,r14
400576: 44 89 ff mov edi,r15d
400579: 41 ff 14 dc call QWORD PTR [r12+rbx*8]
40057d: 48 83 c3 01 add rbx,0x1
400581: 48 39 eb cmp rbx,rbp
400584: 75 ea jne 400570 <__libc_csu_init+0x40>
400586: 48 83 c4 08 add rsp,0x8
40058a: 5b pop rbx
40058b: 5d pop rbp
40058c: 41 5c pop r12
40058e: 41 5d pop r13
400590: 41 5e pop r14
400592: 41 5f pop r15
400594: c3 ret
400595: 90 nop
400596: 66 2e 0f 1f 84 00 00 nop WORD PTR cs:[rax+rax*1+0x0]
40059d: 00 00 00
00000000004005a0 <__libc_csu_fini>:
4005a0: f3 c3 repz ret
Disassembly of section .fini:
00000000004005a4 <_fini>:
4005a4: 48 83 ec 08 sub rsp,0x8
4005a8: 48 83 c4 08 add rsp,0x8
4005ac: c3