On Mon, Jan 12, 2009 at 11:02:17AM -0800, Linus Torvalds wrote: > > Something at the back of my mind said "aliasing". > > > > $ gcc linus.c -O2 -S ; grep subl linus.s > > subl $1624, %esp > > $ gcc linus.c -O2 -S -fno-strict-aliasing; grep subl linus.s > > subl $824, %esp > > > > That's with 4.3.2. > > Interesting. > > Nonsensical, but interesting.
What I find nonsensical is that -fno-strict-aliasing generates better code here. Normally one would expect the compiler seeing more aliases with that option and then be more conservative regarding any sharing. But it seems to be the other way round here. -Andi -- a...@linux.intel.com -- Speaking for myself only. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
