From patchwork Thu Dec  2 15:42:29 2010
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Subject: 0005-Switch-Core-2-to-new-tuning
Date: Thu, 02 Dec 2010 05:42:29 -0000
From: H.J. Lu <hjl.tools@gmail.com>
X-Patchwork-Id: 73982
Message-Id: <AANLkTimkEjFp0FcywoCrzf+i--4HF5FA7B--_NfD8-6U@mail.gmail.com>
To: Uros Bizjak <ubizjak@gmail.com>
Cc: Maxim Kuvyrkov <maxim@codesourcery.com>,
 Jack Howarth <howarth@bromo.med.uc.edu>,
 Richard Henderson <rth@redhat.com>, gcc-patches <gcc-patches@gcc.gnu.org>

On Wed, Dec 1, 2010 at 1:50 PM, Uros Bizjak <ubizjak@gmail.com> wrote:
> On Wed, Dec 1, 2010 at 10:37 AM, Maxim Kuvyrkov <maxim@codesourcery.com> wrote:
>> On Dec 1, 2010, at 3:00 AM, Jack Howarth wrote:
>>
>>> On Tue, Nov 30, 2010 at 01:51:41PM +0100, Uros Bizjak wrote:
>>>> On Tue, Nov 30, 2010 at 1:39 PM, Maxim Kuvyrkov <maxim@codesourcery.com> wrote:
>>>>> This patch switches Core 2 to "new" tuning that Core i7 uses.
>>>>>
>>>>> The "new" tuning very much resembles tuning for generic32 and generic64 CPUs.  Generic tuning appears to provide best performance results on Core 2/i7 hardware.
>>>>>
>>>>> OK for trunk?
>>>>
>>>> Can you please summarize SPEC2k, SPEC2k6 and Polyhedron results for
>>>> patched and unpatched gcc?
>>>>
>>>> Thanks,
>>>> Uros.
>>>
>>> Uros,
>>>   On x86-apple-darwin10, benchmarking the Polyhedron 2005 suite using a dual 2.8 GHz
>>> Xeon 2008 MacPro, I get the following results with -mtune=generic and -mtune=core2
>>> at -m64 and -m32. These are for r167305 with both 0005-Switch-Core-2-to-new-tuning
>>> and 0006-Core-2-i7-DFA applied.
>>> ...
>>> It is interesting that at -m32, -mtune=core2 shows a net
>>> improvement whereas at -m64 that option is a wash compared
>>> to -mtune=generic.
>>
>> That's what I expected.  Jack, thanks for testing the patches on Polyhedron benchmarks.
>
> Thanks to H.J. and Jack for the results. These results are no worse
> than existing "generic" scheduling. Since this patch is mainly tuning
> (with a new DFA, of course), it is OK for mainline even in stage 3.
>
> We are all looking forward for H.J.'s experimental stuff ;)
>

Here is the first one.  OK for trunk?

Thanks.


diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 97477a0..7e76521 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -3495,12 +3495,12 @@ ix86_option_override_internal (bool main_args_p)
 
 	      case PROCESSOR_CORE2_64:
 		ix86_tune = PROCESSOR_CORE2_32;
-		ix86_schedule = CPU_PENTIUMPRO;
+		ix86_schedule = CPU_CORE2;
 		break;
 
 	      case PROCESSOR_COREI7_64:
 		ix86_tune = PROCESSOR_COREI7_32;
-		ix86_schedule = CPU_PENTIUMPRO;
+		ix86_schedule = CPU_COREI7;
 		break;
 
 	      default: