ARM支持的數據寬度

ARM 處理器支持6種數據類型;

8位有符號和無符號字節。 (char, unsigned char)

16位有符號和無符號半字，它們以2字節的邊界對准。(short int, unsigned short int)

32位有符號和無符號字，它們以4字節的邊界對准。(int, unsigned int)

ARM指令全是以32bit的字並且必須是字對准的。

Thumb指令是半字而且必以兩字節的邊界對准的。

1. #include <stdio.h>
2. #include <stdlib.h>
4. void main()
5. {
6. printf("sizeof(char) = %d\n", sizeof(char));
7. printf("sizeof(short) = %d\n", sizeof(short));
8. printf("sizeof(int) = %d\n", sizeof(int));
9. printf("sizeof(long) = %d\n", sizeof(long));
10. printf("sizeof(float) = %d\n", sizeof(float));
11. printf("sizeof(double) = %d\n", sizeof(double));

運行結果：

1. [[email protected] width]# arm-linux-gcc arm-width.c -o arm-width
2. [[email protected] width]# ./arm-width
3. sizeof(char) = 1
4. sizeof(short) = 2
5. sizeof(int) = 4
6. sizeof(long) = 4
7. sizeof(float) = 4
8. sizeof(double) = 8
9. [[email protected] width]#