On 07/03/2013 04:25 PM, Pedro Alves wrote:
> On 07/03/2013 08:22 PM, Luis Machado wrote:
>> On 07/03/2013 12:05 PM, Pedro Alves wrote:
>>> On 07/02/2013 07:50 PM, Luis Machado wrote:
>>>> -
>>>> -if {[istarget "spu*-*-*"]} then {
>>>> -    # The internal address format used for the combined Cell/B.E.
>>>> -    # debugger requires 64-bit.
>>>> -    set is64bitonly "yes"
>>>> -}
>>>> -
>>>
>>> I'm not sure this equates to sizeof pointer == 64-bit.
>>> This bit may need to be retained.  [Adding Ulrich].
>>
>> Fair enough. Ulrich, let me know if the pointer check in the attached
>> patch doesn't make sense for Cell BE.
>>
>>>
>>>> +
>>>> +    set sizeof_function_ptr [get_sizeof "void (*)(void)" 8]
>>>> +    set sizeof_data_ptr [get_sizeof "void *" 8]
>>>> +    if {${sizeof_function_ptr} != 4 && ${sizeof_data_ptr} != 4} then {
>>>> +	set is64bitonly "yes"
>>>> +    }
>>>> +}
>>>> +
>>>
>>> srec (etc.) is most used in small embedded targets (e.g., those
>>> that include dsrec.o in the configure.tgt), consequently
>>> that's where the test is most useful.  Such targets
>>> are the most likely to have 16-bit pointers (< 4 bytes).
>>> E.g., h8300, etc.  Looks like this ends up causing the tests to
>>> be skipped there too.  IOW, a better check would be:
>>>
>>>      if {${sizeof_function_ptr} > 4 || ${sizeof_data_ptr} > 4} then {
>>>
>>
>> Ah, yes. This check is indeed better. Follows an updated patch that does
>> this.
>>
>>> But, this change also means we have reduced routine-checking,
>>> as most people test on x86_64.  I think we can do better.  The test
>>> works fine on e.g., x86_64, because programs get linked to low (< 32-bit)
>>> addresses by default.  That's the point of:
>>>
>>> if [istarget "alpha*-*-*"] then {
>>>       # SREC etc cannot handle 64-bit addresses.  Force the test
>>>       # program into the low 31 bits of the address space.
>>>       lappend options "additional_flags=-Wl,-taso"
>>> }
>>>
>>> (For MIPS N64, if you wanted, I guess you could do similarly
>>>    to Alpha, and rebuild with:
>>>
>>>     lappend options "ldflags=-Wl,-Tdata=0x600000"
>>>
>>>    to force use of low addresses.)
>>>
>>> IOW, instead of checking for ABI pointer sizes, I think it'd
>>> be better to test for the actual address size of one the
>>> variables dumped.  That is, check that &intarray is < 32-bit.
>>>
>>
>> If lack of coverage for x86_64 running things on low addresses is a
>> problem, we can add an exception for x86_64, what do you think? Adding
>> these exceptions usually polute the testcases though.
>
> But do you see a problem with checking whether "&intarray is < 32-bit" instead?
>

Not really. Like so?

Luis