1 2 #include <stdio.h> 3 #include <stdlib.h> 4 5 void do_fsave_interesting_stuff ( void* p ) 6 { 7 asm __volatile__("fninit"); 8 asm __volatile__("fldpi"); 9 asm __volatile__("fld1"); 10 asm __volatile__("fldln2"); 11 asm __volatile__("fsave (%0)" : : "r" (p) : "memory" ); 12 } 13 14 void do_fsave ( void* p ) 15 { 16 asm __volatile__("fsave (%0)" : : "r" (p) : "memory" ); 17 } 18 19 void do_frstor ( void* p ) 20 { 21 asm __volatile__("frstor (%0)" : : "r" (p) : "memory" ); 22 } 23 24 25 int isFPLsbs ( int i ) 26 { 27 int q; 28 q = 0; if (i == q || i == q+1) return 1; 29 q = 10; if (i == q || i == q+1) return 1; 30 q = 20; if (i == q || i == q+1) return 1; 31 q = 30; if (i == q || i == q+1) return 1; 32 q = 40; if (i == q || i == q+1) return 1; 33 q = 50; if (i == q || i == q+1) return 1; 34 q = 60; if (i == q || i == q+1) return 1; 35 q = 70; if (i == q || i == q+1) return 1; 36 return 0; 37 } 38 39 void show_fpustate ( unsigned char* buf, int hide64to80 ) 40 { 41 int i; 42 printf(" 0 "); 43 for (i = 0; i < 14; i++) 44 printf("%02x ", buf[i]); 45 printf("\n"); 46 47 printf(" 14 "); 48 for (i = 14; i < 28; i++) 49 printf("%02x ", buf[i]); 50 printf("\n"); 51 52 for (i = 0; i < 80; i++) { 53 if ((i % 10) == 0) 54 printf("%3d ", i+28); 55 if (hide64to80 && isFPLsbs(i)) 56 printf("xx "); 57 else 58 printf("%02x ", buf[i+28]); 59 if (i > 0 && ((i % 10) == 9)) 60 printf("\n"); 61 } 62 } 63 64 int main ( int argc, char** argv ) 65 { 66 unsigned short* buf1 = malloc(54*sizeof(short)); 67 unsigned short* buf2 = malloc(54*sizeof(short)); 68 int xx = argc > 1; 69 printf("Re-run with any arg to suppress least-significant\n" 70 " 16 bits of FP numbers\n"); 71 72 /* Create an initial image. */ 73 do_fsave_interesting_stuff(buf1); 74 show_fpustate( (unsigned char*)buf1, xx ); 75 76 /* Reload it into buf2. */ 77 do_frstor(buf1); 78 do_fsave(buf2); 79 show_fpustate( (unsigned char*)buf2, xx ); 80 81 return 0; 82 } 83
