YunQiang Su <yunqiang...@cipunited.com> 于2021年8月31日周二 下午7:09写道：
>
> Currently, the enums from define_c_enum and define_enum can only
> has values one by one from 0.
>
> In fact we can support the behaviour just like C, aka like
> (define_enum "mips_isa" [(mips1 1) mips2 (mips32 32) mips32r2]),
> then we can get
> enum mips_isa {
> MIPS_ISA_MIPS1 = 1,
> MIPS_ISA_MIPS2 = 2,
> MIPS_ISA_MIPS32 = 32,
> MIPS_ISA_MIPS32R2 = 33
> };
>
> gcc/ChangeLog:
> * read-md.c (md_reader::handle_enum): support value assignation.
> * doc/md.texi: record define_c_enum value assignation support.
> ---
> gcc/doc/md.texi | 4 ++++
> gcc/read-md.c | 28 ++++++++++++++++++++++++----
> 2 files changed, 28 insertions(+), 4 deletions(-)
>
> diff --git a/gcc/doc/md.texi b/gcc/doc/md.texi
> index f8047aefc..2b41cb7fb 100644
> --- a/gcc/doc/md.texi
> +++ b/gcc/doc/md.texi
> @@ -11074,6 +11074,8 @@ The syntax is as follows:
> (define_c_enum "@var{name}" [
> @var{value0}
> @var{value1}
> + (@var{value32} 32)
> + @var{value33}
> @dots{}
> @var{valuen}
> ])
> @@ -11086,6 +11088,8 @@ in @file{insn-constants.h}:
> enum @var{name} @{
> @var{value0} = 0,
> @var{value1} = 1,
> + @var{value32} = 32,
> + @var{value33} = 33,
> @dots{}
> @var{valuen} = @var{n}
> @};
> diff --git a/gcc/read-md.c b/gcc/read-md.c
> index bb419e0f6..2d01c69fc 100644
> --- a/gcc/read-md.c
> +++ b/gcc/read-md.c
> @@ -902,7 +902,9 @@ void
> md_reader::handle_enum (file_location loc, bool md_p)
> {
> char *enum_name, *value_name;
> - struct md_name name;
> + unsigned int cur_value;
> + struct md_name name, value;
> + bool value_given;
This flag is not needed at all. So please ignore V2.
See V3 please.
> struct enum_type *def;
> struct enum_value *ev;
> void **slot;
> @@ -928,6 +930,7 @@ md_reader::handle_enum (file_location loc, bool md_p)
> *slot = def;
> }
>
> + cur_value = def->num_values;
> require_char_ws ('[');
>
> while ((c = read_skip_spaces ()) != ']')
> @@ -937,28 +940,45 @@ md_reader::handle_enum (file_location loc, bool md_p)
> error_at (loc, "unterminated construct");
> exit (1);
> }
> - unread_char (c);
> - read_name (&name);
> + value_given = false;
> + if (c == '(')
> + {
> + read_name (&name);
> + read_name (&value);
> + require_char_ws (')');
> + cur_value = atoi(value.string);
> + value_given = true;
> + }
> + else
> + {
> + unread_char (c);
> + read_name (&name);
> + }
>
> ev = XNEW (struct enum_value);
> ev->next = 0;
> if (md_p)
> {
> value_name = concat (def->name, "_", name.string, NULL);
> + if (value_given)
> + cur_value = atoi (value.string);
> upcase_string (value_name);
> ev->name = xstrdup (name.string);
> }
> else
> {
> value_name = xstrdup (name.string);
> + if (value_given)
> + cur_value = atoi (value.string);
> ev->name = value_name;
> }
> ev->def = add_constant (get_md_constants (), value_name,
> - md_decimal_string (def->num_values), def);
> + md_decimal_string (cur_value), def);
>
> *def->tail_ptr = ev;
> def->tail_ptr = &ev->next;
> def->num_values++;
> + cur_value++;
> }
> }
>
> --
> 2.30.2
>
