test/tools/llvm-opt-report/Inputs/sr2.c

   1 /*
   2 ** Write a 64-bit variable-length integer to memory starting at p[0].
   3 ** The length of data write will be between 1 and 9 bytes.  The number
   4 ** of bytes written is returned.
   5 **
   6 ** A variable-length integer consists of the lower 7 bits of each byte
   7 ** for all bytes that have the 8th bit set and one byte with the 8th
   8 ** bit clear.  Except, if we get to the 9th byte, it stores the full
   9 ** 8 bits and is the last byte.
  10 */
  11 SQLITE_PRIVATE int sqlite3PutVarint(unsigned char *p, u64 v){
  12   int i, j, n;
  13   u8 buf[10];
  14   if( v & (((u64)0xff000000)<<32) ){
  15     p[8] = v;
  16     v >>= 8;
  17     for(i=7; i>=0; i--){
  18       p[i] = (v & 0x7f) | 0x80;
  19       v >>= 7;
  20     }
  21     return 9;
  22   }
  23   n = 0;
  24   do{
  25     buf[n++] = (v & 0x7f) | 0x80;
  26     v >>= 7;
  27   }while( v!=0 );
  28   buf[0] &= 0x7f;
  29   assert( n<=9 );
  30   for(i=0, j=n-1; j>=0; j--, i++){
  31     p[i] = buf[j];
  32   }
  33   return n;
  34 }
  35