Re: [PATCH] testsuite: Make sure double-precision is supported in g++.dg/eh/arm-vfp-unwind.C

[Richard Earnshaw <Richard.Earnshaw@foss.arm.com>]

On 26/08/2021 16:53, Christophe Lyon via Gcc-patches wrote:
> g++.dg/eh/arm-vfp-unwind.C uses an asm statement relying on
> double-precision FPU support, but does not make sure it is actually
> supported by the target.
> Check (__ARM_FP & 8) to ensure this.
> 
> 2021-08-26  Christophe Lyon  <christophe.lyon@foss.st.com>
> 
> 	gcc/testsuite/
> 	* g++.dg/eh/arm-vfp-unwind.C: Check __ARM_FP.
> ---
>   gcc/testsuite/g++.dg/eh/arm-vfp-unwind.C | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/gcc/testsuite/g++.dg/eh/arm-vfp-unwind.C b/gcc/testsuite/g++.dg/eh/arm-vfp-unwind.C
> index 62263c0c3b0..90d20081d78 100644
> --- a/gcc/testsuite/g++.dg/eh/arm-vfp-unwind.C
> +++ b/gcc/testsuite/g++.dg/eh/arm-vfp-unwind.C
> @@ -3,7 +3,7 @@
>   
>   /* Test to catch off-by-one errors in arm/pr-support.c.  */
>   
> -#if defined (__VFP_FP__) && !defined (__SOFTFP__)
> +#if defined (__VFP_FP__) && !defined (__SOFTFP__) && (__ARM_FP & 8)
>   
>   #include <iostream>
>   #include <stdlib.h>
> 

Wouldn't it be better to have an alternate to the asm for the case where 
we only have single-precision float?  Something like (untested):

static void donkey ()
{
#if __ARM_FP & 8
   asm volatile ("fcpyd d9, %P0" : : "w" (1.2345) : "d9");
#else
   asm volatile ("fcpys s18, %P0" : : "w" (1.2345f) : "s18");
#endif
   throw 1;
}

R.