On 17/08/16 09:23, Richard Biener wrote: > On Tue, Aug 16, 2016 at 6:06 PM, Jeff Law <l...@redhat.com> wrote: >> On 08/16/2016 08:01 AM, Tamar Christina wrote: >>> >>> >>> Hi All, >>> >>> This patch turns off the usage of section anchors for >>> declarations that do not fit in a single anchor range. >>> A large enough object will use the full anchor range >>> and also force the use of another anchor pointer. >>> >>> By not using an anchor for large objects more globals >>> can share the same anchor. >>> >>> The patch has been benchmarked using Spec2000 and >>> the impact on performance is negligible, however some files >>> using large arrays showed a appreciable reduction in amount of >>> instructions in the assembly file. >>> >>> Regression tests were run on aarch64-none-elf and no regressions. >>> >>> Ok for trunk? >>> >>> 2016-08-16 Tamar Christina <tamar.christ...@arm.com> >>> Ramana Radhakrishnan <ramana.radhakrish...@arm.com> >>> >>> * gcc/varasm.c >>> (default_use_anchors_for_symbol_p): Reject too large decls. >> >> Do you have to worry about DECL_SIZE being non-constant here or are those >> filtered out earlier? > > Globals can't have variable size. >
And Common variables (which may change size at link time) can't go in anchor groups. Nor, for that matter, can anything that's preemtible at link time. R. > Richard. > >> jeff >
