Re: [PATCH 3/11] Add MIPS_MAX_REGISTER_SIZE (2/4)

[Yao Qi <qiyaoltc at gmail dot com>]

Alan Hayward <Alan.Hayward@arm.com> writes:

>  }
>
> +/* Supply register REGNUM, whose contents are stored in signed VAL, to
> +   REGCACHE.  */
> +
> +void
> +regcache::raw_supply_signed (int regnum, LONGEST val)

The unsigned version of this function is also needed, because I see such
pattern also exists,

      store_unsigned_integer (buf, 8, byte_order, sp + offset);
      regcache_raw_supply (regcache, AMD64_RSP_REGNUM, buf);

this leads me thinking we need to use function template to define
functions for both LONGEST and ULONGEST.

Secondly, this method can be named as raw_supply.

> +{
> +  enum bfd_endian byte_order = gdbarch_byte_order (m_descr->gdbarch);
> +  gdb_byte *regbuf;
> +  size_t size;
> +
> +  gdb_assert (regnum >= 0 && regnum < m_descr->nr_raw_registers);
> +  gdb_assert (!m_readonly_p);
> +
> +  regbuf = register_buffer (regnum);
> +  size = m_descr->sizeof_register[regnum];
> +
> +  store_signed_integer (regbuf, size, byte_order, val);
> +  m_register_status[regnum] = REG_VALID;
> +}
> +
>  /* Collect register REGNUM from REGCACHE and store its contents in BUF.  */
>
>  void
> @@ -1251,6 +1271,23 @@ regcache::raw_collect (int regnum, void *buf) const
>    memcpy (buf, regbuf, size);
>  }
>
> +/* Collect register REGNUM from REGCACHE and extract its contents into a signed

This line is too long.

> +   LONGEST.  */
> +
> +LONGEST
> +regcache::raw_collect_signed (int regnum) const

We can define this method like this,

template<typename T>
using LongType = typename std::enable_if<(std::is_same<T, LONGEST>::value
					  || std::is_same<T, ULONGEST>::value),
					 T>::type;

  template<typename T>
  LongType<T> raw_collect (int regnum) const
  {
    ....
    if (std::is_signed<T>::value)
      return extract_signed_integer (regbuf, size, byte_order);
    else
      return extract_unsigned_integer (regbuf, size, byte_order);
  }

> +{
> +  enum bfd_endian byte_order = gdbarch_byte_order (m_descr->gdbarch);
> +  const gdb_byte *regbuf;
> +  size_t size;
> +
> +  gdb_assert (regnum >= 0 && regnum < m_descr->nr_raw_registers);
> +
> +  regbuf = register_buffer (regnum);
> +  size = m_descr->sizeof_register[regnum];
> +  return extract_signed_integer (regbuf, size, byte_order);
> +}

If you want, we can add a function template for extract_signed_integer
and extract_unsigned_integer.

template<typename T>
LongType<T>
extract_integer (const gdb_byte *addr, int len, enum bfd_endian byte_order)
{
  T retval;

  ...
  if (std::is_signed<T>::value)
    {
      ...
    }
  else
    {
      ...
    }
  return retval;
}

so, the raw_collect above becomes, 

  template<typename T>
  LongType<T> raw_collect (int regnum) const
  {
    ....
    return extract_integer<T> (regbuf, size, byte_order);
  }

and raw_read_{signed,unsigned}, cooked_read_{signed,unsigned} can be
merged as function template too.

-- 
Yao (齐尧)