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 15/09/2021 13:26, Christophe LYON via Gcc-patches wrote:
> 
> On 15/09/2021 13:02, Richard Earnshaw wrote:
>>
>>
>> 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;
>> }
> 
> 
> I tried similar things but they failed on some testing configurations.
> 
> Let me try your version, I'll let you know if there is any fallout.

Of course, the asm syntax should be converted to the new 'unified 
syntax' form ie vmov.f{32,64}.

R.

> 
> Christophe
> 
> 
>>
>> R.