Hi Mike,
On Tue, Oct 23, 2018 at 04:12:11PM -0400, Michael Meissner wrote:
> This patch changes the name used by the <math>l built-in functions that return
> or are passed long double if the long double type is changed from the current
> IBM long double format to the IEEE 128-bit format.
>
> I have done a bootstrap and make check with no regressions on a little endian
> power8 system. Is it ok to check into the trunk? This will need to be back
> ported to the GCC 8.x branch.
Could you test it on the usual assortment of systems instead of just one?
BE 7 and 8, LE 8 and 9. Or wait for possible fallout :-)
A backport to 8 is wanted yes, but please wait as usual. It's fine after
a week or so of no problems.
> +/* On 64-bit Linux and Freebsd systems, possibly switch the long double
> library
> + function names from <foo>l to <foo>f128 if the default long double type is
> + IEEE 128-bit. Typically, with the C and C++ languages, the standard
> math.h
> + include file switches the names on systems that support long double as
> IEEE
> + 128-bit, but that doesn't work if the user uses __builtin_<foo>l directly
> or
> + if they use Fortran. Use the TARGET_MANGLE_DECL_ASSEMBLER_NAME hook to
> + change this name. We only do this if the default is long double is not
> IEEE
> + 128-bit, and the user asked for IEEE 128-bit. */
s/default is/default/
Does this need some synchronisation with the libm headers? I guess things
will just work out, but it is desirable if libm stops doing this with
compilers that have this change?
> +static tree
> +rs6000_mangle_decl_assembler_name (tree decl, tree id)
> +{
> + if (!TARGET_IEEEQUAD_DEFAULT && TARGET_IEEEQUAD && TARGET_LONG_DOUBLE_128
Write this is in the opposite order?
if (TARGET_LONG_DOUBLE_128 && TARGET_IEEEQUAD && !TARGET_IEEEQUAD_DEFAULT
> + {
> + size_t len = IDENTIFIER_LENGTH (id);
> + const char *name = IDENTIFIER_POINTER (id);
> +
> + if (name[len-1] == 'l')
> + {
> + bool has_long_double_p = false;
> + tree type = TREE_TYPE (decl);
> + machine_mode ret_mode = TYPE_MODE (type);
> +
> + /* See if the function returns long double or long double
> + complex. */
> + if (ret_mode == TFmode || ret_mode == TCmode)
> + has_long_double_p = true;
This comment is a bit misleading I think? The code checks if it is the
same mode as would be used for long double, not if that is the actual
asked-for type. The code is fine AFAICS, the comment isn't so great
though.
> + else
> + {
> + function_args_iterator args_iter;
> + tree arg;
> +
> + /* See if we have a long double or long double complex
> + argument. */
And same here.
> + FOREACH_FUNCTION_ARGS (type, arg, args_iter)
> + {
> + machine_mode arg_mode = TYPE_MODE (arg);
> + if (arg_mode == TFmode || arg_mode == TCmode)
> + {
> + has_long_double_p = true;
> + break;
> + }
> + }
> + }
> +
> + /* If we have long double, change the name. */
And this.
> + if (has_long_double_p)
> + {
> + char *name2 = (char *) alloca (len + 4);
> + memcpy (name2, name, len-1);
len - 1
Okay for trunk with those things fixed. Thanks!
Segher
