On 29 April 2015 at 01:24, Andrew Pinski <pins...@gmail.com> wrote: > On Tue, Dec 16, 2014 at 2:19 AM, Renlin Li <renlin...@arm.com> wrote: >> Hi all, >> >> This is a simple patch to add another two ACLE 2.0 predefined macros into >> aarch64 backend. >> They are __ARM_ALIGN_MAX_PWR and __ARM_ALIGN_MAX_STACK_PWR. Currently, those >> two values are hard-wired to 16. >> >> The following clauses from ACLE 2.0 documentation indicate the meaning of >> those two macros: >> >> The macro __ARM_ALIGN_MAX_STACK_PWR indicates (as the exponent of a power of >> 2) the maximum available stack alignment. >> The macro __ARM_ALIGN_MAX_PWR indicates (as the exponent of a power of 2) >> the maximum available alignment of static data. >> >> aarch64-none-elf target is tested on on the model. No new regression. >> >> Is it Okay for trunk? > > Have you tested these alignments? That is have we tested 65536 > alignment for both stack and static data? > I suspect the stack alignment that is support is not 64k but much > smaller. And the supported static data alignment is much larger, > maybe 20 or more.
Looks to me __ARM_ALIGN_MAX_STACK_PWR can be lifted to 2^16 without issue. GCC won't gripe about the static data alignment until 2^29. Aside from the latter being rather conservative I think we should add a test case to the testsuite for each. RenLin can you prep a testcase? /Marcus