[Lightning] Re: PATCH - Correct comparison of float branch test on i386

[Paulo César Pereira de Andrade]

Paolo Bonzini wrote:
> On 08/18/2010 09:15 PM, Paulo César Pereira de Andrade wrote:
>>    Now, changing it to
>> #define FLOAT_BRANCH_WORKS   1
>> I get a problem in x86_64... The attached patch is somewhat simple
>> minded, and just a suggestion of possible way to correct the issue.
>> Since the macros UCOMISSrr and UCOMISDrr are called in other places,
>> and some of the float branch test macros have a longer body, I added
>> jit_fp_btest receiving only one argument.
>>
>>    With this change, it now works correctly in x86_64 also, with either
>> approach to branch on float compare.
>>
>>    Please review.
>
> Thanks, looks good, but I inlined jit_fp_btest inside every use instead.
>
> Paolo

  I just git pull'ed lightning, but it still misses returning the
patch address.

  In my testing tool:
$ ./lightning ldst.tst
ldst.tst:176: error: bad patch
(1 prepare 1 prepare_d 2 extr_f_d %f0 %f0 pusharg_d %f0 extr_f_d %f1 %f1
pu...)

that means that it got null/0 as the patch address. Actually, it should
be extended to check if the address returned is in bounds of
>= code_start and < code_end, or instead of < code_end, use
<= jit_get_label() (I will add this change to the testing tool).

Paulo