lib/zlib_dfltcc/dfltcc_util.h

   1 // SPDX-License-Identifier: Zlib
   2 #ifndef DFLTCC_UTIL_H
   3 #define DFLTCC_UTIL_H
   4
   5 #include <linux/zutil.h>
   6
   7 /*
   8  * C wrapper for the DEFLATE CONVERSION CALL instruction.
   9  */
  10 typedef enum {
  11     DFLTCC_CC_OK = 0,
  12     DFLTCC_CC_OP1_TOO_SHORT = 1,
  13     DFLTCC_CC_OP2_TOO_SHORT = 2,
  14     DFLTCC_CC_OP2_CORRUPT = 2,
  15     DFLTCC_CC_AGAIN = 3,
  16 } dfltcc_cc;
  17
  18 #define DFLTCC_QAF 0
  19 #define DFLTCC_GDHT 1
  20 #define DFLTCC_CMPR 2
  21 #define DFLTCC_XPND 4
  22 #define HBT_CIRCULAR (1 << 7)
  23 #define HB_BITS 15
  24 #define HB_SIZE (1 << HB_BITS)
  25
  26 static inline dfltcc_cc dfltcc(
  27     int fn,
  28     void *param,
  29     Byte **op1,
  30     size_t *len1,
  31     const Byte **op2,
  32     size_t *len2,
  33     void *hist
  34 )
  35 {
  36     Byte *t2 = op1 ? *op1 : NULL;
  37     size_t t3 = len1 ? *len1 : 0;
  38     const Byte *t4 = op2 ? *op2 : NULL;
  39     size_t t5 = len2 ? *len2 : 0;
  40     register int r0 __asm__("r0") = fn;
  41     register void *r1 __asm__("r1") = param;
  42     register Byte *r2 __asm__("r2") = t2;
  43     register size_t r3 __asm__("r3") = t3;
  44     register const Byte *r4 __asm__("r4") = t4;
  45     register size_t r5 __asm__("r5") = t5;
  46     int cc;
  47
  48     __asm__ volatile(
  49                      ".insn rrf,0xb9390000,%[r2],%[r4],%[hist],0\n"
  50                      "ipm %[cc]\n"
  51                      : [r2] "+r" (r2)
  52                      , [r3] "+r" (r3)
  53                      , [r4] "+r" (r4)
  54                      , [r5] "+r" (r5)
  55                      , [cc] "=r" (cc)
  56                      : [r0] "r" (r0)
  57                      , [r1] "r" (r1)
  58                      , [hist] "r" (hist)
  59                      : "cc", "memory");
  60     t2 = r2; t3 = r3; t4 = r4; t5 = r5;
  61
  62     if (op1)
  63         *op1 = t2;
  64     if (len1)
  65         *len1 = t3;
  66     if (op2)
  67         *op2 = t4;
  68     if (len2)
  69         *len2 = t5;
  70     return (cc >> 28) & 3;
  71 }
  72
  73 static inline int is_bit_set(
  74     const char *bits,
  75     int n
  76 )
  77 {
  78     return bits[n / 8] & (1 << (7 - (n % 8)));
  79 }
  80
  81 static inline void turn_bit_off(
  82     char *bits,
  83     int n
  84 )
  85 {
  86     bits[n / 8] &= ~(1 << (7 - (n % 8)));
  87 }
  88
  89 static inline int dfltcc_are_params_ok(
  90     int level,
  91     uInt window_bits,
  92     int strategy,
  93     uLong level_mask
  94 )
  95 {
  96     return (level_mask & (1 << level)) != 0 &&
  97         (window_bits == HB_BITS) &&
  98         (strategy == Z_DEFAULT_STRATEGY);
  99 }
 100
 101 char *oesc_msg(char *buf, int oesc);
 102
 103 #endif /* DFLTCC_UTIL_H */