Jeff Layton <jlay...@redhat.com> wrote: > 0xffffffff813ae828 <+136>: je 0xffffffff813ae83a <ima_file_free+154> > 0xffffffff813ae82a <+138>: mov 0x150(%rbp),%rcx > 0xffffffff813ae831 <+145>: shr %rcx > 0xffffffff813ae834 <+148>: cmp %rcx,0x20(%rax) > 0xffffffff813ae838 <+152>: je 0xffffffff813ae862 <ima_file_free+194>
Is it possible there's a stall between the load of RCX and the subsequent instructions because they all have to wait for RCX to become available? The interleaving between operating on RSI and RCX in the older code might alleviate that. In addition, the load if the 20(%rax) value is now done in the CMP instruction rather than earlier, so it might not get speculatively loaded in time, whereas the earlier code explicitly loads it up front. David
