Most are within 10. The largest one I see is 17 across all benchmark.
Dehao
On Fri, Oct 25, 2013 at 4:21 PM, Xinliang David Li <davi...@google.com> wrote:
> What is the usual number of iterations?
>
> David
>
> On Fri, Oct 25, 2013 at 4:10 PM, Dehao Chen <de...@google.com> wrote:
>> If the propagation finds an infinite look, if the in-edge count is
>> non-zero, then it will cause compiler go into infinite loop when
>> building with AutoFDO.
>>
>> Bootstrapped and regression test on-going.
>>
>> OK for google-4_8 branch?
>>
>> Thanks,
>> Dehao
>>
>> Index: gcc/auto-profile.c
>> ===================================================================
>> --- gcc/auto-profile.c (revision 204027)
>> +++ gcc/auto-profile.c (working copy)
>> @@ -1287,6 +1287,7 @@ afdo_propagate (void)
>> {
>> basic_block bb;
>> bool changed = true;
>> + int i = 0;
>>
>> FOR_ALL_BB (bb)
>> {
>> @@ -1295,7 +1296,7 @@ afdo_propagate (void)
>> bb->flags |= BB_ANNOTATED;
>> }
>>
>> - while (changed)
>> + while (changed && i++ < PARAM_VALUE
>> (PARAM_AUTOFDO_MAX_PROPAGATE_ITERATIONS))
>> {
>> changed = false;
>>
>> Index: gcc/params.def
>> ===================================================================
>> --- gcc/params.def (revision 204027)
>> +++ gcc/params.def (working copy)
>> @@ -460,6 +460,14 @@ DEFPARAM(PARAM_MAX_PREDICTED_ITERATIONS,
>> "The maximum number of loop iterations we predict statically",
>> 100, 0, 0)
>>
>> +/* This parameter controls the maximum iterations that AutoFDO profile
>> + prpagation algorithm will run for a specific CFG. */
>> +
>> +DEFPARAM(PARAM_AUTOFDO_MAX_PROPAGATE_ITERATIONS,
>> + "max-autofdo-max-propagate-iterations",
>> + "The maximum number of AutoFDO profile propagation iterations",
>> + 1000, 0, 0)
>> +
>> /* This parameter controls the probability of builtin_expect. The default
>> value is 90%. This empirical value is obtained through the weighted
>> probability of FDO counters (with the FDO count value as the weight)
