On Mon, Apr 06, 2020 at 12:25:27PM +0200, Christophe Leroy wrote: > > if (ppc_inst_prefixed(x) != ppc_inst_prefixed(y)) > > return false; > > else if (ppc_inst_prefixed(x)) > > return !memcmp(&x, &y, sizeof(struct ppc_inst)); > > Are we sure memcmp() is a good candidate for the comparison ? Can we do > simpler ? Especially, I understood a prefixed instruction is a 64 bits > properly aligned instruction, can we do a simple u64 compare ? Or is GCC > intelligent enough to do that without calling memcmp() function which is > heavy ?
A prefixed insn is *not* 8-byte aligned, it is 4-byte aligned, fwiw. memcmp() isn't as heavy as you fear, not with a non-ancient GCC at least. But this could be written in a nicer way, sure :-) Segher
