Hi, Continuing investigation of fails on bootstrap I found next problem (besides the problem with unknown alignment described above): there is a mess with size_needed and epilogue_size_needed when we generate epilogue loop which also use SSE-moves, but no unrolled - that's probably the reason of the fails we saw.
Please check the attached patch - though the full testing isn't over
yet. bootstraps seem to be ok as well as arrayarg.f90-test (with
sse_loop enabled).
On 19 November 2011 05:38, Jan Hubicka <hubi...@ucw.cz> wrote:
>> Given that x86 memset/memcpy is still broken, I think we should revert
>> it for now.
>
> Well, looking into the code, the SSE alignment issues needs work - the
> alignment test merely tests whether some alignmnet is known not whether 16
> byte
> alignment is known that is the cause of failures in 32bit bootstrap. I
> originally
> convinced myself that this is safe since we soot for unaligned load/stores
> anyway.
>
>
> I've commited the following patch that disabled SSE codegen and unbreaks atom
> bootstrap. This seems more sensible to me given that the patch cumulated some
> good improvements on the non-SSE path as well and we could return into the SSE
> alignment issues incremntally. There is still falure in the fortran testcase
> that I am convinced is previously latent issue.
>
> I will be offline tomorrow. If there are futher serious problems, just fell
> free to revert the changes and we could look into them for next stage1.
>
> Honza
>
> * i386.c (atom_cost): Disable SSE loop until alignment issues are
> fixed.
> Index: i386.c
> ===================================================================
> --- i386.c (revision 181479)
> +++ i386.c (working copy)
> @@ -1783,18 +1783,18 @@ struct processor_costs atom_cost = {
> /* stringop_algs for memcpy.
> SSE loops works best on Atom, but fall back into non-SSE unrolled loop
> variant
> if that fails. */
> - {{{libcall, {{4096, sse_loop}, {4096, unrolled_loop}, {-1, libcall}}}, /*
> Known alignment. */
> - {libcall, {{4096, sse_loop}, {4096, unrolled_loop}, {-1, libcall}}}},
> - {{libcall, {{2048, sse_loop}, {2048, unrolled_loop}, {-1, libcall}}}, /*
> Unknown alignment. */
> - {libcall, {{2048, sse_loop}, {2048, unrolled_loop},
> + {{{libcall, {{4096, unrolled_loop}, {-1, libcall}}}, /* Known alignment.
> */
> + {libcall, {{4096, unrolled_loop}, {-1, libcall}}}},
> + {{libcall, {{2048, unrolled_loop}, {-1, libcall}}}, /* Unknown alignment.
> */
> + {libcall, {{2048, unrolled_loop},
> {-1, libcall}}}}},
>
> /* stringop_algs for memset. */
> - {{{libcall, {{4096, sse_loop}, {4096, unrolled_loop}, {-1, libcall}}}, /*
> Known alignment. */
> - {libcall, {{4096, sse_loop}, {4096, unrolled_loop}, {-1, libcall}}}},
> - {{libcall, {{1024, sse_loop}, {1024, unrolled_loop}, /* Unknown
> alignment. */
> + {{{libcall, {{4096, unrolled_loop}, {-1, libcall}}}, /* Known alignment.
> */
> + {libcall, {{4096, unrolled_loop}, {-1, libcall}}}},
> + {{libcall, {{1024, unrolled_loop}, /* Unknown alignment. */
> {-1, libcall}}},
> - {libcall, {{2048, sse_loop}, {2048, unrolled_loop},
> + {libcall, {{2048, unrolled_loop},
> {-1, libcall}}}}},
> 1, /* scalar_stmt_cost. */
> 1, /* scalar load_cost. */
--
---
Best regards,
Michael V. Zolotukhin,
Software Engineer
Intel Corporation.
memfunc_epilogue_loops.patch
Description: Binary data
