On Thu, Dec 03, 2020 at 11:06:12PM -0500, Michael Meissner wrote:
> +proc check_effective_target_ppc_long_double_ibm { } {
> + return [check_cached_effective_target ppc_long_double_ibm {
> + int main()
> + {
> + #if !defined(_ARCH_PPC) || !defined(__LONG_DOUBLE_IBM128__)
> + return 1;
> + #else
> + return 0;
> + #endif
> + }
> + }]
> +}
OK.
> +proc check_effective_target_ppc_long_double_ieee { } {
> + return [check_cached_effective_target ppc_long_double_ieee {
> + int main()
> + {
> + #if !defined(_ARCH_PPC) || !defined(__LONG_DOUBLE_IEEE128__)
> + return 1;
> + #else
> + return 0;
> + #endif
> + }
> + }]
> +}
OK.
These names could be without "_ppc", if the functions were defined more
generically. It's not clear that will be useful right now though.
> +# Like check_effective_target_ppc_long_double_ibm, but check if we can
> +# explicitly override the long double format to use the IBM 128-bit extended
> +# double format, and GLIBC supports doing this override by switching the
> +# sprintf to handle long double.
This comment needs work.
> +proc check_effective_target_ppc_long_double_override_ibm { } {
> + set options "-mlong-double-128 -mabi=ibmlongdouble -Wno-psabi"
> + check_runtime_nocache ppc_long_double_ovveride_ibm {
It is spelled "override".
> + #include <string.h>
> + #include <stdio.h>
> + volatile __ibm128 a = (__ibm128) 3.0;
> + volatile long double one = 1.0L;
> + volatile long double two = 2.0L;
> + volatile long double b;
> + char buffer[20];
> + int main()
> + {
> + #if !defined(_ARCH_PPC) || !defined(__LONG_DOUBLE_IBM128__)
> + return 1;
> + #else
> + b = one + two;
> + if (memcmp ((void *)&a, (void *)&b, sizeof (long double)) != 0)
The pointer casts are unnecessary, and can be harmful.
You should use sizeof(b) , and check that sizeof(a) == sizeof(b) .
> + return 1;
> + sprintf (buffer, "%lg", b);
> + return strcmp (buffer, "3") != 0;
> + #endif
> + }
> + } $options
> +}
The name of this should say it is something to do with libc, or even
glibc in fact ("lg" is not portable), and with text output.
> +# Like check_effective_target_ppc_long_double_ieee, but check if we can
> +# explicitly override the long double format to use the IEEE 128-bit format,
> +# and GLIBC supports doing this override by switching the sprintf to handle
> +# long double.
> +
> +proc check_effective_target_ppc_long_double_override_ieee { } {
> + set options "-mlong-double-128 -mabi=ieeelongdouble -Wno-psabi"
> + check_runtime_nocache ppc_long_double_ovveride_ieee {
> + #include <string.h>
> + #include <stdio.h>
> + volatile _Float128 a = 3.0f128;
> + volatile long double one = 1.0L;
> + volatile long double two = 2.0L;
> + volatile long double b;
> + char buffer[20];
> + int main()
> + {
> + #if !defined(_ARCH_PPC) || !defined(__LONG_DOUBLE_IEEE128__)
> + return 1;
> + #else
> + b = one + two;
> + if (memcmp ((void *)&a, (void *)&b, sizeof (long double)) != 0)
> + return 1;
> + sprintf (buffer, "%lg", b);
> + return strcmp (buffer, "3") != 0;
> + #endif
> + }
> + } $options
> +}
Ditto.
> +# See if the target is a powerpc with the long double format that is
> 128-bits.
> +
> +proc check_effective_target_ppc_long_double_128bit { } {
> + return [check_cached_effective_target ppc_long_double_128bit {
> + int main()
> + {
> + #ifndef _ARCH_PPC
> + return 1;
> + #else
> + return sizeof (long double) != 16;
> + #endif
> + }
> + }]
> +}
In this case checking for PowerPC seems a really bad design: this is
obviously exactly the same on any architecture.
> +proc check_effective_target_ppc_long_double_64bit { } {
> + return [check_cached_effective_target ppc_long_double_64bit {
> + int main()
> + {
> + #ifndef _ARCH_PPC
> + return 1;
> + #else
> + return sizeof (long double) != 8;
> + #endif
> + }
> + }]
> +}
Ditto.
Segher
