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[PATCH/AARCH64] Improve ThunderX2 T99 address cost model

From: Andrew Pinski <apinski at cavium dot com>
To: GCC Patches <gcc-patches at gcc dot gnu dot org>
Date: Mon, 23 Jan 2017 15:35:22 -0800
Subject: [PATCH/AARCH64] Improve ThunderX2 T99 address cost model
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Hi,
  On ThunderX 2, the logical shifts that are part of the address cause
a 1 cycle extra and this is not modeled correctly.  For induction
variables we don't want to do the shift.  When I change the cost for
the shift of the addresses, I get a 12% improvement on HMMER; all over
benchmarks in SPEC CPU 2006 were neutral.

OK? Bootstrapped and tested on aarch64-linux-gnu with no regressions.

Thanks,
Andrew Pinski

ChangeLog:
* config/aarch64/aarch64.c (thunderx2t99_addrcost_table): Improve cost table.

Attachment: improve-t2addresscost.diff.txt
Description: Text document

Follow-Ups:
- Re: [PATCH/AARCH64] Improve ThunderX2 T99 address cost model
  - From: Richard Earnshaw

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