A new ia32 backend

craig@jcb-sc.com craig@jcb-sc.com
Wed Jun 16 06:51:00 GMT 1999


>Richard Henderson wrote in < 19990615224736.A29894@cygnus.com >: 
>
>>...
>>	while (a--) { /* nothing dependant on a */ }
>>    becomes
>>	if (a) do { ... } while (--a);
>>...
>
>Is it really equivalent? Even if `(a == 0)' just before
>the two lines?

No, good point, there needs to be an `else --a;' added to the
`if' clause.  (Presumably the actual code in the compiler is
correct, but it's always good to check, as well as make sure
these email'ed "doclets" are correct as well!)

        tq vm, (burley)


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