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Re: Determine more IVs to be non-overflowing


On Tue, 5 Jul 2016, Richard Biener wrote:

given widest_int has only precision of TImode on x86_64?

Is that the case? The comments say:

     It is really finite precision math where the precision is 4 times the
     size of the largest integer that the target port can represent.

And the target has

/* Keep the OI and XI modes from confusing the compiler into thinking
   that these modes could actually be used for computation.  They are
   only holders for vectors during data movement.  */
#define MAX_BITSIZE_MODE_ANY_INT (128)

I would thus expect widest_int to have at 512 bits on x86_64 (possibly more depending on the exact definition of largest integer).

--
Marc Glisse


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