> The IBM LTC team has tested the benefit of -frename-registers at -O2 > and sees no net benefit for PowerPC -- some benchmarks improve > slightly but others degrade slightly (a few percent). You mentioned > no overall benefit for x86. Although you mentioned benefit for > Itanium, it is not a primary nor secondary architecture target for GCC > and continues to have limited adoption. Andreas also reported a > bootstrap comparison failure for Itanium due to the change.
...which had nothing to do with -frename-registers but was a latent issue in the speculation support of the scheduler, see the audit trail. -- Eric Botcazou