2 * Copyright 1985, 1988 by the Massachusetts Institute of Technology.
4 * For copying and distribution information, please
5 * see the file <mit-cpyright.h>.
7 * This routine generates the P permutation code for the DES.
10 #include <afsconfig.h>
11 #include <afs/param.h>
14 #include <mit-cpyright.h>
17 #include "des_internal.h"
19 #include "des_prototypes.h"
24 /* P permutes 32 bit input R1 into 32 bit output R2 */
26 /* clear the output */
27 fprintf(stream, " L2 = 0;\n");
29 fprintf(stream, " R2 = 0;\n");
30 fprintf(stream, "/* P operations */\n/* from right to right */\n");
31 /* first list mapping from left to left */
32 for (i = 0; i <= 31; i++)
34 fprintf(stream, " if (R1 & (1<<%d)) R2 |= 1<<%d;\n", P[i], i);
36 /* flip p into p_temp */
37 fprintf(stream, " P_temp = R1;\n");
38 fprintf(stream, " P_temp_p = (unsigned char *) &P_temp;\n");
40 #ifdef AFS_DARWIN80_ENV
41 fprintf(stream, "#if defined(__i386__) || defined(__amd64__)\n");
42 fprintf(stream, " R2 = P_prime[0][*P_temp_p++];\n");
43 fprintf(stream, " R2 |= P_prime[1][*P_temp_p++];\n");
44 fprintf(stream, " R2 |= P_prime[2][*P_temp_p++];\n");
45 fprintf(stream, " R2 |= P_prime[3][*P_temp_p];\n");
46 fprintf(stream, "#elif defined(__ppc__) || defined(__ppc64__)\n");
47 fprintf(stream, " R2 = P_prime[3][*P_temp_p++];\n");
48 fprintf(stream, " R2 |= P_prime[2][*P_temp_p++];\n");
49 fprintf(stream, " R2 |= P_prime[1][*P_temp_p++];\n");
50 fprintf(stream, " R2 |= P_prime[0][*P_temp_p];\n");
51 fprintf(stream, "#else\n#error Unsupported architecture\n#endif\n");
52 #else /* !AFS_DARWIN80_ENV */
54 fprintf(stream, " R2 = P_prime[0][*P_temp_p++];\n");
55 fprintf(stream, " R2 |= P_prime[1][*P_temp_p++];\n");
56 fprintf(stream, " R2 |= P_prime[2][*P_temp_p++];\n");
57 fprintf(stream, " R2 |= P_prime[3][*P_temp_p];\n");
59 fprintf(stream, " R2 = P_prime[3][*P_temp_p++];\n");
60 fprintf(stream, " R2 |= P_prime[2][*P_temp_p++];\n");
61 fprintf(stream, " R2 |= P_prime[1][*P_temp_p++];\n");
62 fprintf(stream, " R2 |= P_prime[0][*P_temp_p];\n");
64 #endif /* !AFS_DARWIN80_ENV */