include/gdbstub/helpers.h

   1 /*
   2  * gdbstub helpers
   3  *
   4  * These are all used by the various frontends and have to be host
   5  * aware to ensure things are store in target order.
   6  *
   7  * Copyright (c) 2022 Linaro Ltd
   8  *
   9  * SPDX-License-Identifier: GPL-2.0-or-later
  10  */
  11
  12 #ifndef _GDBSTUB_HELPERS_H_
  13 #define _GDBSTUB_HELPERS_H_
  14
  15 #ifndef COMPILING_PER_TARGET
  16 #error "gdbstub helpers should only be included by target specific code"
  17 #endif
  18
  19 #include "exec/tswap.h"
  20 #include "cpu-param.h"
  21
  22 /*
  23  * The GDB remote protocol transfers values in target byte order. As
  24  * the gdbstub may be batching up several register values we always
  25  * append to the array.
  26  */
  27
  28 static inline int gdb_get_reg8(GByteArray *buf, uint8_t val)
  29 {
  30     g_byte_array_append(buf, &val, 1);
  31     return 1;
  32 }
  33
  34 static inline int gdb_get_reg16(GByteArray *buf, uint16_t val)
  35 {
  36     uint16_t to_word = tswap16(val);
  37     g_byte_array_append(buf, (uint8_t *) &to_word, 2);
  38     return 2;
  39 }
  40
  41 static inline int gdb_get_reg32(GByteArray *buf, uint32_t val)
  42 {
  43     uint32_t to_long = tswap32(val);
  44     g_byte_array_append(buf, (uint8_t *) &to_long, 4);
  45     return 4;
  46 }
  47
  48 static inline int gdb_get_reg64(GByteArray *buf, uint64_t val)
  49 {
  50     uint64_t to_quad = tswap64(val);
  51     g_byte_array_append(buf, (uint8_t *) &to_quad, 8);
  52     return 8;
  53 }
  54
  55 static inline int gdb_get_reg128(GByteArray *buf, uint64_t val_hi,
  56                                  uint64_t val_lo)
  57 {
  58     uint64_t to_quad;
  59 #if TARGET_BIG_ENDIAN
  60     to_quad = tswap64(val_hi);
  61     g_byte_array_append(buf, (uint8_t *) &to_quad, 8);
  62     to_quad = tswap64(val_lo);
  63     g_byte_array_append(buf, (uint8_t *) &to_quad, 8);
  64 #else
  65     to_quad = tswap64(val_lo);
  66     g_byte_array_append(buf, (uint8_t *) &to_quad, 8);
  67     to_quad = tswap64(val_hi);
  68     g_byte_array_append(buf, (uint8_t *) &to_quad, 8);
  69 #endif
  70     return 16;
  71 }
  72
  73 static inline int gdb_get_zeroes(GByteArray *array, size_t len)
  74 {
  75     guint oldlen = array->len;
  76     g_byte_array_set_size(array, oldlen + len);
  77     memset(array->data + oldlen, 0, len);
  78
  79     return len;
  80 }
  81
  82 /**
  83  * gdb_get_reg_ptr: get pointer to start of last element
  84  * @len: length of element
  85  *
  86  * This is a helper function to extract the pointer to the last
  87  * element for additional processing. Some front-ends do additional
  88  * dynamic swapping of the elements based on CPU state.
  89  */
  90 static inline uint8_t *gdb_get_reg_ptr(GByteArray *buf, int len)
  91 {
  92     return buf->data + buf->len - len;
  93 }
  94
  95 #if TARGET_LONG_BITS == 64
  96 #define gdb_get_regl(buf, val) gdb_get_reg64(buf, val)
  97 #define ldtul_p(addr) ldq_p(addr)
  98 #else
  99 #define gdb_get_regl(buf, val) gdb_get_reg32(buf, val)
 100 #define ldtul_p(addr) ldl_p(addr)
 101 #endif
 102
 103 #endif /* _GDBSTUB_HELPERS_H_ */