Re: [PATCH] pkl: Get rid of string literals as exception names

[Jose E. Marchesi]

Hi Mohammad.

> 2022-01-27  Mohammad-Reza Nabipoor  <mnabipoor@gnu.org>
>
>       * libpoke/pvm.h (PVM_EXCEPTIONS): New macro.
>       * libpoke/pvm.jitter (wrapped-globals): Add `pvm_exception_names`.
>       (PVM_RAISE_DFL): Use `pvm_exception_names` instead of string
>       literals.
>       (late-c): Define `pvm_exception_names`.
> ---
>
> Hello, Jose.
>
> With this patch, I declare ARMv7 as a "supported" platform :)

Related to this: I see these comments that Luca left when he first
turned Jitter in poke to use non-threaded mode:

  # XXX make non-relocatable: see raise

Luca, was it because of these string constants, or because the raising
of the exceptions?  If the first, we can remove the comments once this
patch gets applied.

>
>                 === poke Summary ===
>               
>               # of expected passes            6258
>               # of unsupported tests          7
>               
>
> Regards,
> Mohammad-Reza
>
>
>  etc/pvm-wraps-static-whitelist |  1 +
>  libpoke/pvm.h                  | 21 +++++++++++++++++++++
>  libpoke/pvm.jitter             |  9 ++++++++-
>  3 files changed, 30 insertions(+), 1 deletion(-)
>
> diff --git a/etc/pvm-wraps-static-whitelist b/etc/pvm-wraps-static-whitelist
> index 8886c0a9..5f08f93e 100644
> --- a/etc/pvm-wraps-static-whitelist
> +++ b/etc/pvm-wraps-static-whitelist
> @@ -12,6 +12,7 @@ pvm_literal_invalid_class
>  pvm_literal_eindex
>  pvm_literal_notmappable
>  pvm_literal_newline
> +pvm_exception_names
>  pvm_memcpy
>  pvm_strlen
>  pvm_strcpy
> diff --git a/libpoke/pvm.h b/libpoke/pvm.h
> index 4baee433..0980675e 100644
> --- a/libpoke/pvm.h
> +++ b/libpoke/pvm.h
> @@ -491,6 +491,27 @@ enum pvm_exit_code
>  /* Exceptions.  These should be in sync with the exception code macros
>     in libpoke.h, and variables and exception names, declared in pkl-rt.pk */
>  
> +#define PVM_EXCEPTIONS(E)    \
> +  E(GENERIC)                 \
> +  E(DIV_BY_ZERO)             \
> +  E(NO_IOS)                  \
> +  E(NO_RETURN)               \
> +  E(OUT_OF_BOUNDS)           \
> +  E(MAP_BOUNDS)              \
> +  E(EOF)                     \
> +  E(MAP)                     \
> +  E(CONV)                    \
> +  E(ELEM)                    \
> +  E(CONSTRAINT)              \
> +  E(IO)                      \
> +  E(SIGNAL)                  \
> +  E(IOFLAGS)                 \
> +  E(INVAL)                   \
> +  E(EXIT)                    \
> +  E(ASSERT)                  \
> +  E(OVERFLOW)                \
> +  E(PERM)
> +
>  #define PVM_E_GENERIC       0
>  #define PVM_E_GENERIC_NAME "generic"
>  #define PVM_E_GENERIC_ESTATUS 1
> diff --git a/libpoke/pvm.jitter b/libpoke/pvm.jitter
> index 0cb1cf7d..8d95a155 100644
> --- a/libpoke/pvm.jitter
> +++ b/libpoke/pvm.jitter
> @@ -163,6 +163,7 @@ wrapped-globals
>    pvm_literal_notmappable
>    pvm_literal_newline
>    libpoke_term_if
> +  pvm_exception_names
>  end
>  
>  
> @@ -288,7 +289,7 @@ late-header-c
>  #define PVM_RAISE_DFL(BASE)                                           \
>   do                                                                   \
>   {                                                                    \
> -   PVM_RAISE (BASE,BASE##_NAME,BASE##_ESTATUS);                        \
> +   PVM_RAISE (BASE,pvm_exception_names[BASE],BASE##_ESTATUS);         \
>   } while (0)
>  
>      /* Macros to implement different kind of instructions.  These are to
> @@ -909,6 +910,12 @@ late-c
>      static const char *pvm_literal_notmappable = "not mappable value";
>      static const char *pvm_literal_newline = "\n";
>  
> +#define E(key) [PVM_E_##key] = PVM_E_##key##_NAME,
> +    static const char *pvm_exception_names[] = {
> +      PVM_EXCEPTIONS(E)
> +    };
> +#undef E
> +
>      static int
>      pvm_nanosleep (const struct timespec *rqtp, struct timespec *rmtp)
>      {

I think the table of exception names should be in pvm.h, not in
pvm.jitter.  And it would be better to define it in a portable way,
without array initializers:

const char *pvm_exception_names[] =
{
  PVM_E_GENERIC_NAME,
  ...
};

After the release I will put all the C side of the exception information
in a pkl-exception.def file.  But for now the above will suffice.

Thanks!