int B = 5;
による変換
5E 23 ...
| 高水準言語 int B = 5; |
|
言語プロセッサ による変換 |
|
機械語 5E 23 ... |
CPUが実行するプログラムは機械語とか機械語プログラムと言われる。
「プログラム実行のしくみ」中の機械語のプログラムにあるように、5E 23 56 F3 3E FE D3 71 CD ...... というようなもので、ニーモニックを書き加えて多少理解しやすく書いたものは次のようになっている。
| 番地 | 機械語 | ニーモニック |
| D000 | 5E | LD E,(HL) |
| D001 | 23 | INC HL |
| D002 | 56 | LD D,(HL) |
| D003 | F3 | DI |
| D004 | 3E FE | LD A,FE |
| D006 | D3 71 | OUT (71),A |
| ............ | ||
この機械語でプログラムを組むのは手間がかかるので、人間にわかりやすい書き方をしたものをコンピュータを使って機械語へ書き直すことを考えた。上記のニーモニックはその最も簡単なもので、これにいろいろな機能を加えて発展させたものをアセンブリ言語という。
この機械語への変換をするソフトウェアを言語プロセッサという。
アセンブリ言語は対象となるCPUによって書き方が異なるし、まだまだ人間にはわかりにくい。そこでさらに人間の言葉に近い言語から変換できるようになっていった。このような言語を高水準言語あるいは高級言語という。
高水準言語には、FORTRAN, BASIC, C, C++, Java などたくさん存在する。目的により使い分けるが時代と共に流行もある。
高水準言語から、機械語に変換することを「翻訳」ということがある。
高水準言語から、機械語に変換する方法は大きく分けてコンパイラ方式とインタプリタ方式がある。
コンパイラではファイルが作成され、OS上で直接実行される
| ソースプログラム ファイル |
|
コンパイラによる変換 オブジェクトプログラムの生成 |
|
オブジェクトプログラム ファイル |
|
OSから実行 |
インタプリタでは変換しながら実行もする
| ソースプログラム ファイル |
|
インタプリタによる変換 と実行 |
実際には途中で中間言語に変換することもあるので、簡単に2つに分類できないこともある。
たとえば Java という言語では、コンパイルにより中間言語のファイルを作った後、javaというプログラムで中間言語を解釈しながら実行する。後半の仕組みはインタプリタと同じ動作である。
有名なCのプログラム例を実際にコンパイルしてみます。まずはソースファイルを作ります。次のプログラムを書いてHello.cという名前で保存します。
#include <stdio.h>
int main(void)
{
printf("Hello, World!\n");
return 0;
}
コンパイルします。
$ gcc Hello.c -o Hello
Helloという名前のファイルができています。
$ ls -l -rwx------ 1 hoge hoge 6273 2009-05-06 20:00 Hello -rw------- 1 hoge hoge 82 2009-05-06 20:00 Hello.c
実行します。
$ ./Hello Hello, World!
この時実行されるのはHello.cではなくコンパイルして作成されたHelloです。
Hello.cを調べます。fileというコマンドで調べることができます。
$ file Hello.c Hello.c: ASCII C program text
ASCIIで書かれたテキストファイルでCのプログラムだといっています。
テキストファイルならばcatコマンドで内容を表示できます。
$ cat Hello.c
#include <stdio.h>
int main(void)
{
printf("Hello, World!\n");
return 0;
}
ではコンパイルの結果作成されたHelloをfileコマンドで調べると
$ file Hello Hello: ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.6.8, not stripped
このファィルはcatコマンドで表示するとまともに読めません。hdコマンドでコードを見ることができます。
$ hd Hello 00000000 7f 45 4c 46 01 01 01 00 00 00 00 00 00 00 00 00 |.ELF............| 00000010 02 00 03 00 01 00 00 00 10 83 04 08 34 00 00 00 |............4...| 00000020 c8 06 00 00 00 00 00 00 34 00 20 00 07 00 28 00 |........4. ...(.| 00000030 1e 00 1b 00 06 00 00 00 34 00 00 00 34 80 04 08 |........4...4...| 00000040 34 80 04 08 e0 00 00 00 e0 00 00 00 05 00 00 00 |4...............| 00000050 04 00 00 00 03 00 00 00 14 01 00 00 14 81 04 08 |................| 00000060 14 81 04 08 13 00 00 00 13 00 00 00 04 00 00 00 |................| 00000070 01 00 00 00 01 00 00 00 00 00 00 00 00 80 04 08 |................| 00000080 00 80 04 08 b4 04 00 00 b4 04 00 00 05 00 00 00 |................| 00000090 00 10 00 00 01 00 00 00 b4 04 00 00 b4 94 04 08 |................| 000000a0 b4 94 04 08 08 01 00 00 10 01 00 00 06 00 00 00 |................| 000000b0 00 10 00 00 02 00 00 00 c8 04 00 00 c8 94 04 08 |................| 000000c0 c8 94 04 08 d0 00 00 00 d0 00 00 00 06 00 00 00 |................| 000000d0 04 00 00 00 04 00 00 00 28 01 00 00 28 81 04 08 |........(...(...| 000000e0 28 81 04 08 44 00 00 00 44 00 00 00 04 00 00 00 |(...D...D.......| 000000f0 04 00 00 00 51 e5 74 64 00 00 00 00 00 00 00 00 |....Q.td........| 00000100 00 00 00 00 00 00 00 00 00 00 00 00 06 00 00 00 |................| 00000110 04 00 00 00 2f 6c 69 62 2f 6c 64 2d 6c 69 6e 75 |..../lib/ld-linu| 00000120 78 2e 73 6f 2e 32 00 00 04 00 00 00 10 00 00 00 |x.so.2..........| 00000130 01 00 00 00 47 4e 55 00 00 00 00 00 02 00 00 00 |....GNU.........| 00000140 06 00 00 00 12 00 00 00 04 00 00 00 14 00 00 00 |................| 00000150 03 00 00 00 47 4e 55 00 b1 f8 ed c8 35 10 d0 5b |....GNU.....5..[| 00000160 15 37 26 d7 6c 83 c9 05 df 2c 66 8a 03 00 00 00 |.7&.l....,f.....| 00000170 05 00 00 00 01 00 00 00 03 00 00 00 04 00 00 00 |................| 00000180 00 00 00 00 00 00 00 00 00 00 00 00 02 00 00 00 |................| 00000190 00 00 00 00 02 00 00 00 04 00 00 00 01 00 00 00 |................| 000001a0 05 00 00 00 00 20 00 20 00 00 00 00 04 00 00 00 |..... . ........| 000001b0 ad 4b e3 c0 00 00 00 00 00 00 00 00 00 00 00 00 |.K..............| 000001c0 00 00 00 00 01 00 00 00 00 00 00 00 00 00 00 00 |................| 000001d0 20 00 00 00 2e 00 00 00 00 00 00 00 00 00 00 00 | ...............| 000001e0 12 00 00 00 29 00 00 00 00 00 00 00 00 00 00 00 |....)...........| 000001f0 12 00 00 00 1a 00 00 00 9c 84 04 08 04 00 00 00 |................| 00000200 11 00 10 00 00 5f 5f 67 6d 6f 6e 5f 73 74 61 72 |.....__gmon_star| 00000210 74 5f 5f 00 6c 69 62 63 2e 73 6f 2e 36 00 5f 49 |t__.libc.so.6._I| 00000220 4f 5f 73 74 64 69 6e 5f 75 73 65 64 00 70 75 74 |O_stdin_used.put| 00000230 73 00 5f 5f 6c 69 62 63 5f 73 74 61 72 74 5f 6d |s.__libc_start_m| 00000240 61 69 6e 00 47 4c 49 42 43 5f 32 2e 30 00 00 00 |ain.GLIBC_2.0...| 00000250 00 00 02 00 02 00 01 00 01 00 01 00 10 00 00 00 |................| 00000260 10 00 00 00 00 00 00 00 10 69 69 0d 00 00 02 00 |.........ii.....| 00000270 40 00 00 00 00 00 00 00 98 95 04 08 06 01 00 00 |@...............| 00000280 a8 95 04 08 07 01 00 00 ac 95 04 08 07 02 00 00 |................| 00000290 b0 95 04 08 07 03 00 00 55 89 e5 53 83 ec 04 e8 |........U..S....| 000002a0 00 00 00 00 5b 81 c3 f8 12 00 00 8b 93 fc ff ff |....[...........| 000002b0 ff 85 d2 74 05 e8 1e 00 00 00 e8 e1 00 00 00 e8 |...t............| 000002c0 8c 01 00 00 58 5b c9 c3 ff 35 a0 95 04 08 ff 25 |....X[...5.....%| 000002d0 a4 95 04 08 00 00 00 00 ff 25 a8 95 04 08 68 00 |.........%....h.| 000002e0 00 00 00 e9 e0 ff ff ff ff 25 ac 95 04 08 68 08 |.........%....h.| 000002f0 00 00 00 e9 d0 ff ff ff ff 25 b0 95 04 08 68 10 |.........%....h.| 00000300 00 00 00 e9 c0 ff ff ff 00 00 00 00 00 00 00 00 |................| 00000310 31 ed 5e 89 e1 83 e4 f0 50 54 52 68 e0 83 04 08 |1.^.....PTRh....| 00000320 68 f0 83 04 08 51 56 68 c4 83 04 08 e8 b7 ff ff |h....QVh........| 00000330 ff f4 90 90 90 90 90 90 90 90 90 90 90 90 90 90 |................| 00000340 55 89 e5 53 83 ec 04 80 3d bc 95 04 08 00 75 3f |U..S....=.....u?| 00000350 a1 c0 95 04 08 bb c0 94 04 08 81 eb bc 94 04 08 |................| 00000360 c1 fb 02 83 eb 01 39 d8 73 1e 8d b6 00 00 00 00 |......9.s.......| 00000370 83 c0 01 a3 c0 95 04 08 ff 14 85 bc 94 04 08 a1 |................| 00000380 c0 95 04 08 39 d8 72 e8 c6 05 bc 95 04 08 01 83 |....9.r.........| 00000390 c4 04 5b 5d c3 8d 74 26 00 8d bc 27 00 00 00 00 |..[]..t&...'....| 000003a0 55 89 e5 83 ec 18 a1 c4 94 04 08 85 c0 74 12 b8 |U............t..| 000003b0 00 00 00 00 85 c0 74 09 c7 04 24 c4 94 04 08 ff |......t...$.....| 000003c0 d0 c9 c3 90 55 89 e5 83 e4 f0 83 ec 10 c7 04 24 |....U..........$| 000003d0 a0 84 04 08 e8 1f ff ff ff b8 00 00 00 00 c9 c3 |................| 000003e0 55 89 e5 5d c3 8d 74 26 00 8d bc 27 00 00 00 00 |U..]..t&...'....| 000003f0 55 89 e5 57 56 53 e8 4f 00 00 00 81 c3 a1 11 00 |U..WVS.O........| 00000400 00 83 ec 1c e8 8f fe ff ff 8d bb 18 ff ff ff 8d |................| 00000410 83 18 ff ff ff 29 c7 c1 ff 02 85 ff 74 24 31 f6 |.....)......t$1.| 00000420 8b 45 10 89 44 24 08 8b 45 0c 89 44 24 04 8b 45 |.E..D$..E..D$..E| 00000430 08 89 04 24 ff 94 b3 18 ff ff ff 83 c6 01 39 fe |...$..........9.| 00000440 72 de 83 c4 1c 5b 5e 5f 5d c3 8b 1c 24 c3 90 90 |r....[^_]...$...| 00000450 55 89 e5 53 83 ec 04 a1 b4 94 04 08 83 f8 ff 74 |U..S...........t| 00000460 13 bb b4 94 04 08 66 90 83 eb 04 ff d0 8b 03 83 |......f.........| 00000470 f8 ff 75 f4 83 c4 04 5b 5d c3 90 90 55 89 e5 53 |..u....[]...U..S| 00000480 83 ec 04 e8 00 00 00 00 5b 81 c3 14 11 00 00 e8 |........[.......| 00000490 ac fe ff ff 59 5b c9 c3 03 00 00 00 01 00 02 00 |....Y[..........| 000004a0 48 65 6c 6c 6f 2c 20 57 6f 72 6c 64 21 00 00 00 |Hello, World!...| 000004b0 00 00 00 00 ff ff ff ff 00 00 00 00 ff ff ff ff |................| 000004c0 00 00 00 00 00 00 00 00 01 00 00 00 10 00 00 00 |................| 000004d0 0c 00 00 00 98 82 04 08 0d 00 00 00 7c 84 04 08 |............|...| 000004e0 04 00 00 00 6c 81 04 08 f5 fe ff 6f 94 81 04 08 |....l......o....| 000004f0 05 00 00 00 04 82 04 08 06 00 00 00 b4 81 04 08 |................| 00000500 0a 00 00 00 4a 00 00 00 0b 00 00 00 10 00 00 00 |....J...........| 00000510 15 00 00 00 00 00 00 00 03 00 00 00 9c 95 04 08 |................| 00000520 02 00 00 00 18 00 00 00 14 00 00 00 11 00 00 00 |................| 00000530 17 00 00 00 80 82 04 08 11 00 00 00 78 82 04 08 |............x...| 00000540 12 00 00 00 08 00 00 00 13 00 00 00 08 00 00 00 |................| 00000550 fe ff ff 6f 58 82 04 08 ff ff ff 6f 01 00 00 00 |...oX......o....| 00000560 f0 ff ff 6f 4e 82 04 08 00 00 00 00 00 00 00 00 |...oN...........| 00000570 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| * 00000590 00 00 00 00 00 00 00 00 00 00 00 00 c8 94 04 08 |................| 000005a0 00 00 00 00 00 00 00 00 de 82 04 08 ee 82 04 08 |................| 000005b0 fe 82 04 08 00 00 00 00 00 00 00 00 47 43 43 3a |............GCC:| 000005c0 20 28 44 65 62 69 61 6e 20 34 2e 34 2e 35 2d 38 | (Debian 4.4.5-8| 000005d0 29 20 34 2e 34 2e 35 00 00 2e 73 79 6d 74 61 62 |) 4.4.5...symtab| 000005e0 00 2e 73 74 72 74 61 62 00 2e 73 68 73 74 72 74 |..strtab..shstrt| 000005f0 61 62 00 2e 69 6e 74 65 72 70 00 2e 6e 6f 74 65 |ab..interp..note| 00000600 2e 41 42 49 2d 74 61 67 00 2e 6e 6f 74 65 2e 67 |.ABI-tag..note.g| 00000610 6e 75 2e 62 75 69 6c 64 2d 69 64 00 2e 67 6e 75 |nu.build-id..gnu| 00000620 2e 68 61 73 68 00 2e 64 79 6e 73 79 6d 00 2e 64 |.hash..dynsym..d| 00000630 79 6e 73 74 72 00 2e 67 6e 75 2e 76 65 72 73 69 |ynstr..gnu.versi| 00000640 6f 6e 00 2e 67 6e 75 2e 76 65 72 73 69 6f 6e 5f |on..gnu.version_| 00000650 72 00 2e 72 65 6c 2e 64 79 6e 00 2e 72 65 6c 2e |r..rel.dyn..rel.| 00000660 70 6c 74 00 2e 69 6e 69 74 00 2e 74 65 78 74 00 |plt..init..text.| 00000670 2e 66 69 6e 69 00 2e 72 6f 64 61 74 61 00 2e 65 |.fini..rodata..e| 00000680 68 5f 66 72 61 6d 65 00 2e 63 74 6f 72 73 00 2e |h_frame..ctors..| 00000690 64 74 6f 72 73 00 2e 6a 63 72 00 2e 64 79 6e 61 |dtors..jcr..dyna| 000006a0 6d 69 63 00 2e 67 6f 74 00 2e 67 6f 74 2e 70 6c |mic..got..got.pl| 000006b0 74 00 2e 64 61 74 61 00 2e 62 73 73 00 2e 63 6f |t..data..bss..co| 000006c0 6d 6d 65 6e 74 00 00 00 00 00 00 00 00 00 00 00 |mment...........| 000006d0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| * 000006f0 1b 00 00 00 01 00 00 00 02 00 00 00 14 81 04 08 |................| 00000700 14 01 00 00 13 00 00 00 00 00 00 00 00 00 00 00 |................| 00000710 01 00 00 00 00 00 00 00 23 00 00 00 07 00 00 00 |........#.......| 00000720 02 00 00 00 28 81 04 08 28 01 00 00 20 00 00 00 |....(...(... ...| 00000730 00 00 00 00 00 00 00 00 04 00 00 00 00 00 00 00 |................| 00000740 31 00 00 00 07 00 00 00 02 00 00 00 48 81 04 08 |1...........H...| 00000750 48 01 00 00 24 00 00 00 00 00 00 00 00 00 00 00 |H...$...........| 00000760 04 00 00 00 00 00 00 00 48 00 00 00 05 00 00 00 |........H.......| 00000770 02 00 00 00 6c 81 04 08 6c 01 00 00 28 00 00 00 |....l...l...(...| 00000780 06 00 00 00 00 00 00 00 04 00 00 00 04 00 00 00 |................| 00000790 44 00 00 00 f6 ff ff 6f 02 00 00 00 94 81 04 08 |D......o........| 000007a0 94 01 00 00 20 00 00 00 06 00 00 00 00 00 00 00 |.... ...........| 000007b0 04 00 00 00 04 00 00 00 4e 00 00 00 0b 00 00 00 |........N.......| 000007c0 02 00 00 00 b4 81 04 08 b4 01 00 00 50 00 00 00 |............P...| 000007d0 07 00 00 00 01 00 00 00 04 00 00 00 10 00 00 00 |................| 000007e0 56 00 00 00 03 00 00 00 02 00 00 00 04 82 04 08 |V...............| 000007f0 04 02 00 00 4a 00 00 00 00 00 00 00 00 00 00 00 |....J...........| 00000800 01 00 00 00 00 00 00 00 5e 00 00 00 ff ff ff 6f |........^......o| 00000810 02 00 00 00 4e 82 04 08 4e 02 00 00 0a 00 00 00 |....N...N.......| 00000820 06 00 00 00 00 00 00 00 02 00 00 00 02 00 00 00 |................| 00000830 6b 00 00 00 fe ff ff 6f 02 00 00 00 58 82 04 08 |k......o....X...| 00000840 58 02 00 00 20 00 00 00 07 00 00 00 01 00 00 00 |X... ...........| 00000850 04 00 00 00 00 00 00 00 7a 00 00 00 09 00 00 00 |........z.......| 00000860 02 00 00 00 78 82 04 08 78 02 00 00 08 00 00 00 |....x...x.......| 00000870 06 00 00 00 00 00 00 00 04 00 00 00 08 00 00 00 |................| 00000880 83 00 00 00 09 00 00 00 02 00 00 00 80 82 04 08 |................| 00000890 80 02 00 00 18 00 00 00 06 00 00 00 0d 00 00 00 |................| 000008a0 04 00 00 00 08 00 00 00 8c 00 00 00 01 00 00 00 |................| 000008b0 06 00 00 00 98 82 04 08 98 02 00 00 30 00 00 00 |............0...| 000008c0 00 00 00 00 00 00 00 00 04 00 00 00 00 00 00 00 |................| 000008d0 87 00 00 00 01 00 00 00 06 00 00 00 c8 82 04 08 |................| 000008e0 c8 02 00 00 40 00 00 00 00 00 00 00 00 00 00 00 |....@...........| 000008f0 04 00 00 00 04 00 00 00 92 00 00 00 01 00 00 00 |................| 00000900 06 00 00 00 10 83 04 08 10 03 00 00 6c 01 00 00 |............l...| 00000910 00 00 00 00 00 00 00 00 10 00 00 00 00 00 00 00 |................| 00000920 98 00 00 00 01 00 00 00 06 00 00 00 7c 84 04 08 |............|...| 00000930 7c 04 00 00 1c 00 00 00 00 00 00 00 00 00 00 00 ||...............| 00000940 04 00 00 00 00 00 00 00 9e 00 00 00 01 00 00 00 |................| 00000950 02 00 00 00 98 84 04 08 98 04 00 00 16 00 00 00 |................| 00000960 00 00 00 00 00 00 00 00 04 00 00 00 00 00 00 00 |................| 00000970 a6 00 00 00 01 00 00 00 02 00 00 00 b0 84 04 08 |................| 00000980 b0 04 00 00 04 00 00 00 00 00 00 00 00 00 00 00 |................| 00000990 04 00 00 00 00 00 00 00 b0 00 00 00 01 00 00 00 |................| 000009a0 03 00 00 00 b4 94 04 08 b4 04 00 00 08 00 00 00 |................| 000009b0 00 00 00 00 00 00 00 00 04 00 00 00 00 00 00 00 |................| 000009c0 b7 00 00 00 01 00 00 00 03 00 00 00 bc 94 04 08 |................| 000009d0 bc 04 00 00 08 00 00 00 00 00 00 00 00 00 00 00 |................| 000009e0 04 00 00 00 00 00 00 00 be 00 00 00 01 00 00 00 |................| 000009f0 03 00 00 00 c4 94 04 08 c4 04 00 00 04 00 00 00 |................| 00000a00 00 00 00 00 00 00 00 00 04 00 00 00 00 00 00 00 |................| 00000a10 c3 00 00 00 06 00 00 00 03 00 00 00 c8 94 04 08 |................| 00000a20 c8 04 00 00 d0 00 00 00 07 00 00 00 00 00 00 00 |................| 00000a30 04 00 00 00 08 00 00 00 cc 00 00 00 01 00 00 00 |................| 00000a40 03 00 00 00 98 95 04 08 98 05 00 00 04 00 00 00 |................| 00000a50 00 00 00 00 00 00 00 00 04 00 00 00 04 00 00 00 |................| 00000a60 d1 00 00 00 01 00 00 00 03 00 00 00 9c 95 04 08 |................| 00000a70 9c 05 00 00 18 00 00 00 00 00 00 00 00 00 00 00 |................| 00000a80 04 00 00 00 04 00 00 00 da 00 00 00 01 00 00 00 |................| 00000a90 03 00 00 00 b4 95 04 08 b4 05 00 00 08 00 00 00 |................| 00000aa0 00 00 00 00 00 00 00 00 04 00 00 00 00 00 00 00 |................| 00000ab0 e0 00 00 00 08 00 00 00 03 00 00 00 bc 95 04 08 |................| 00000ac0 bc 05 00 00 08 00 00 00 00 00 00 00 00 00 00 00 |................| 00000ad0 04 00 00 00 00 00 00 00 e5 00 00 00 01 00 00 00 |................| 00000ae0 30 00 00 00 00 00 00 00 bc 05 00 00 1c 00 00 00 |0...............| 00000af0 00 00 00 00 00 00 00 00 01 00 00 00 01 00 00 00 |................| 00000b00 11 00 00 00 03 00 00 00 00 00 00 00 00 00 00 00 |................| 00000b10 d8 05 00 00 ee 00 00 00 00 00 00 00 00 00 00 00 |................| 00000b20 01 00 00 00 00 00 00 00 01 00 00 00 02 00 00 00 |................| 00000b30 00 00 00 00 00 00 00 00 78 0b 00 00 10 04 00 00 |........x.......| 00000b40 1d 00 00 00 2d 00 00 00 04 00 00 00 10 00 00 00 |....-...........| 00000b50 09 00 00 00 03 00 00 00 00 00 00 00 00 00 00 00 |................| 00000b60 88 0f 00 00 fb 01 00 00 00 00 00 00 00 00 00 00 |................| 00000b70 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| 00000b80 00 00 00 00 00 00 00 00 00 00 00 00 14 81 04 08 |................| 00000b90 00 00 00 00 03 00 01 00 00 00 00 00 28 81 04 08 |............(...| 00000ba0 00 00 00 00 03 00 02 00 00 00 00 00 48 81 04 08 |............H...| 00000bb0 00 00 00 00 03 00 03 00 00 00 00 00 6c 81 04 08 |............l...| 00000bc0 00 00 00 00 03 00 04 00 00 00 00 00 94 81 04 08 |................| 00000bd0 00 00 00 00 03 00 05 00 00 00 00 00 b4 81 04 08 |................| 00000be0 00 00 00 00 03 00 06 00 00 00 00 00 04 82 04 08 |................| 00000bf0 00 00 00 00 03 00 07 00 00 00 00 00 4e 82 04 08 |............N...| 00000c00 00 00 00 00 03 00 08 00 00 00 00 00 58 82 04 08 |............X...| 00000c10 00 00 00 00 03 00 09 00 00 00 00 00 78 82 04 08 |............x...| 00000c20 00 00 00 00 03 00 0a 00 00 00 00 00 80 82 04 08 |................| 00000c30 00 00 00 00 03 00 0b 00 00 00 00 00 98 82 04 08 |................| 00000c40 00 00 00 00 03 00 0c 00 00 00 00 00 c8 82 04 08 |................| 00000c50 00 00 00 00 03 00 0d 00 00 00 00 00 10 83 04 08 |................| 00000c60 00 00 00 00 03 00 0e 00 00 00 00 00 7c 84 04 08 |............|...| 00000c70 00 00 00 00 03 00 0f 00 00 00 00 00 98 84 04 08 |................| 00000c80 00 00 00 00 03 00 10 00 00 00 00 00 b0 84 04 08 |................| 00000c90 00 00 00 00 03 00 11 00 00 00 00 00 b4 94 04 08 |................| 00000ca0 00 00 00 00 03 00 12 00 00 00 00 00 bc 94 04 08 |................| 00000cb0 00 00 00 00 03 00 13 00 00 00 00 00 c4 94 04 08 |................| 00000cc0 00 00 00 00 03 00 14 00 00 00 00 00 c8 94 04 08 |................| 00000cd0 00 00 00 00 03 00 15 00 00 00 00 00 98 95 04 08 |................| 00000ce0 00 00 00 00 03 00 16 00 00 00 00 00 9c 95 04 08 |................| 00000cf0 00 00 00 00 03 00 17 00 00 00 00 00 b4 95 04 08 |................| 00000d00 00 00 00 00 03 00 18 00 00 00 00 00 bc 95 04 08 |................| 00000d10 00 00 00 00 03 00 19 00 00 00 00 00 00 00 00 00 |................| 00000d20 00 00 00 00 03 00 1a 00 01 00 00 00 00 00 00 00 |................| 00000d30 00 00 00 00 04 00 f1 ff 0c 00 00 00 b4 94 04 08 |................| 00000d40 00 00 00 00 01 00 12 00 1a 00 00 00 bc 94 04 08 |................| 00000d50 00 00 00 00 01 00 13 00 28 00 00 00 c4 94 04 08 |........(.......| 00000d60 00 00 00 00 01 00 14 00 35 00 00 00 40 83 04 08 |........5...@...| 00000d70 00 00 00 00 02 00 0e 00 4b 00 00 00 bc 95 04 08 |........K.......| 00000d80 01 00 00 00 01 00 19 00 5a 00 00 00 c0 95 04 08 |........Z.......| 00000d90 04 00 00 00 01 00 19 00 68 00 00 00 a0 83 04 08 |........h.......| 00000da0 00 00 00 00 02 00 0e 00 01 00 00 00 00 00 00 00 |................| 00000db0 00 00 00 00 04 00 f1 ff 74 00 00 00 b8 94 04 08 |........t.......| 00000dc0 00 00 00 00 01 00 12 00 81 00 00 00 b0 84 04 08 |................| 00000dd0 00 00 00 00 01 00 11 00 8f 00 00 00 c4 94 04 08 |................| 00000de0 00 00 00 00 01 00 14 00 9b 00 00 00 50 84 04 08 |............P...| 00000df0 00 00 00 00 02 00 0e 00 b1 00 00 00 00 00 00 00 |................| 00000e00 00 00 00 00 04 00 f1 ff b9 00 00 00 9c 95 04 08 |................| 00000e10 00 00 00 00 01 02 17 00 cf 00 00 00 b4 94 04 08 |................| 00000e20 00 00 00 00 00 02 12 00 e0 00 00 00 b4 94 04 08 |................| 00000e30 00 00 00 00 00 02 12 00 f3 00 00 00 c8 94 04 08 |................| 00000e40 00 00 00 00 01 02 15 00 fc 00 00 00 b4 95 04 08 |................| 00000e50 00 00 00 00 20 00 18 00 07 01 00 00 e0 83 04 08 |.... ...........| 00000e60 05 00 00 00 12 00 0e 00 17 01 00 00 10 83 04 08 |................| 00000e70 00 00 00 00 12 00 0e 00 1e 01 00 00 00 00 00 00 |................| 00000e80 00 00 00 00 20 00 00 00 2d 01 00 00 00 00 00 00 |.... ...-.......| 00000e90 00 00 00 00 20 00 00 00 41 01 00 00 98 84 04 08 |.... ...A.......| 00000ea0 04 00 00 00 11 00 10 00 48 01 00 00 7c 84 04 08 |........H...|...| 00000eb0 00 00 00 00 12 00 0f 00 4e 01 00 00 00 00 00 00 |........N.......| 00000ec0 00 00 00 00 12 00 00 00 6b 01 00 00 9c 84 04 08 |........k.......| 00000ed0 04 00 00 00 11 00 10 00 7a 01 00 00 b4 95 04 08 |........z.......| 00000ee0 00 00 00 00 10 00 18 00 87 01 00 00 b8 95 04 08 |................| 00000ef0 00 00 00 00 11 02 18 00 94 01 00 00 c0 94 04 08 |................| 00000f00 00 00 00 00 11 02 13 00 a1 01 00 00 f0 83 04 08 |................| 00000f10 5a 00 00 00 12 00 0e 00 b1 01 00 00 bc 95 04 08 |Z...............| 00000f20 00 00 00 00 10 00 f1 ff bd 01 00 00 c4 95 04 08 |................| 00000f30 00 00 00 00 10 00 f1 ff c2 01 00 00 00 00 00 00 |................| 00000f40 00 00 00 00 12 00 00 00 d2 01 00 00 bc 95 04 08 |................| 00000f50 00 00 00 00 10 00 f1 ff d9 01 00 00 4a 84 04 08 |............J...| 00000f60 00 00 00 00 12 02 0e 00 f0 01 00 00 c4 83 04 08 |................| 00000f70 1c 00 00 00 12 00 0e 00 f5 01 00 00 98 82 04 08 |................| 00000f80 00 00 00 00 12 00 0c 00 00 63 72 74 73 74 75 66 |.........crtstuf| 00000f90 66 2e 63 00 5f 5f 43 54 4f 52 5f 4c 49 53 54 5f |f.c.__CTOR_LIST_| 00000fa0 5f 00 5f 5f 44 54 4f 52 5f 4c 49 53 54 5f 5f 00 |_.__DTOR_LIST__.| 00000fb0 5f 5f 4a 43 52 5f 4c 49 53 54 5f 5f 00 5f 5f 64 |__JCR_LIST__.__d| 00000fc0 6f 5f 67 6c 6f 62 61 6c 5f 64 74 6f 72 73 5f 61 |o_global_dtors_a| 00000fd0 75 78 00 63 6f 6d 70 6c 65 74 65 64 2e 35 39 38 |ux.completed.598| 00000fe0 32 00 64 74 6f 72 5f 69 64 78 2e 35 39 38 34 00 |2.dtor_idx.5984.| 00000ff0 66 72 61 6d 65 5f 64 75 6d 6d 79 00 5f 5f 43 54 |frame_dummy.__CT| 00001000 4f 52 5f 45 4e 44 5f 5f 00 5f 5f 46 52 41 4d 45 |OR_END__.__FRAME| 00001010 5f 45 4e 44 5f 5f 00 5f 5f 4a 43 52 5f 45 4e 44 |_END__.__JCR_END| 00001020 5f 5f 00 5f 5f 64 6f 5f 67 6c 6f 62 61 6c 5f 63 |__.__do_global_c| 00001030 74 6f 72 73 5f 61 75 78 00 48 65 6c 6c 6f 2e 63 |tors_aux.Hello.c| 00001040 00 5f 47 4c 4f 42 41 4c 5f 4f 46 46 53 45 54 5f |._GLOBAL_OFFSET_| 00001050 54 41 42 4c 45 5f 00 5f 5f 69 6e 69 74 5f 61 72 |TABLE_.__init_ar| 00001060 72 61 79 5f 65 6e 64 00 5f 5f 69 6e 69 74 5f 61 |ray_end.__init_a| 00001070 72 72 61 79 5f 73 74 61 72 74 00 5f 44 59 4e 41 |rray_start._DYNA| 00001080 4d 49 43 00 64 61 74 61 5f 73 74 61 72 74 00 5f |MIC.data_start._| 00001090 5f 6c 69 62 63 5f 63 73 75 5f 66 69 6e 69 00 5f |_libc_csu_fini._| 000010a0 73 74 61 72 74 00 5f 5f 67 6d 6f 6e 5f 73 74 61 |start.__gmon_sta| 000010b0 72 74 5f 5f 00 5f 4a 76 5f 52 65 67 69 73 74 65 |rt__._Jv_Registe| 000010c0 72 43 6c 61 73 73 65 73 00 5f 66 70 5f 68 77 00 |rClasses._fp_hw.| 000010d0 5f 66 69 6e 69 00 5f 5f 6c 69 62 63 5f 73 74 61 |_fini.__libc_sta| 000010e0 72 74 5f 6d 61 69 6e 40 40 47 4c 49 42 43 5f 32 |rt_main@@GLIBC_2| 000010f0 2e 30 00 5f 49 4f 5f 73 74 64 69 6e 5f 75 73 65 |.0._IO_stdin_use| 00001100 64 00 5f 5f 64 61 74 61 5f 73 74 61 72 74 00 5f |d.__data_start._| 00001110 5f 64 73 6f 5f 68 61 6e 64 6c 65 00 5f 5f 44 54 |_dso_handle.__DT| 00001120 4f 52 5f 45 4e 44 5f 5f 00 5f 5f 6c 69 62 63 5f |OR_END__.__libc_| 00001130 63 73 75 5f 69 6e 69 74 00 5f 5f 62 73 73 5f 73 |csu_init.__bss_s| 00001140 74 61 72 74 00 5f 65 6e 64 00 70 75 74 73 40 40 |tart._end.puts@@| 00001150 47 4c 49 42 43 5f 32 2e 30 00 5f 65 64 61 74 61 |GLIBC_2.0._edata| 00001160 00 5f 5f 69 36 38 36 2e 67 65 74 5f 70 63 5f 74 |.__i686.get_pc_t| 00001170 68 75 6e 6b 2e 62 78 00 6d 61 69 6e 00 5f 69 6e |hunk.bx.main._in| 00001180 69 74 00 |it.|
コンパイルしたファイルには文字として解釈できない文字がありますから、16進数でバイト列をそのまま表示しています。右の | | で挟まれたところには1バイトの文字と解釈できるものはその文字を、そうでない時は"."を表示しています。
コンパイルはソースを機械語に書き直すといいますが、そう単純ではないことが分かると思います。
実行はOSがこのプログラムHelloをファイルからメモリ上にロードし、始まりの場所をセットして処理を開始させます。Hello側は作業が終わればOSに制御を戻します。これが プログラムソースにあるreturnの意味です。0 は正常に終わったことを知らせるもので、UNIX系OSの取り決めです。
聖愛中学高等学校