On Thu, Mar 24 2016, Andrew Morton <a...@linux-foundation.org> wrote:
> On Thu, 24 Mar 2016 00:42:32 +0100 Rasmus Villemoes > <li...@rasmusvillemoes.dk> wrote: > >> Attach the malloc attribute to a few allocation functions. This helps >> gcc generate better code by telling it that the return value doesn't >> alias any existing pointers (which is even more valuable given the >> pessimizations implied by -fno-strict-aliasing). >> > Shaves 6 bytes off my 1MB i386 defconfig vmlinux. Winner! Well, the full bloat-o-meter summary is add/remove: 0/0 grow/shrink: 72/155 up/down: 1165/-1674 (-509) which sure still isn't much, but this isn't (just) about saving a few bytes, but more about allowing gcc to generate better code; sometimes by not having to reload, but also by enabling it to reorder instructions (e.g. hoisting a load above a store) - the simple example was chosen because it was very easy to see the relationship between the source and the generated code. Anyway, thanks for picking them up. Rasmus
