Integrated: 8255553: [PPC64] Introduce and use setbc and setnbc P10 instructions

[Ziviani]

On Wed, 28 Oct 2020 17:00:43 GMT, Ziviani <github.com+670087+jrziviani at openjdk.org> wrote:

> - setbc RT,BI: sets RT to 1 if CR(BI) is 1, otherwise 0.
> - setnbc RT,BI: sets RT to -1 if CR(BI) is 1, otherwise 0.
> Ref: PowerISA 3.1, page 129.
> 
> These instructions are particularly interesting to improve the following
> pattern `(src1<src2)? -1: ((src1>src2)? 1: 0)`, which can be found in
> `instruct cmpL3_reg_reg_ExEx()@ppc.ad`, by removing its branches.
> 
> Long.toString, that generate such pattern in getChars, has showed a
> good performance gain by using these new instructions.
> 
> Example:
> for (int i = 0; i < 200_000; i++)
>   res = Long.toString((long)i);
> 
> java -Xcomp -XX:CompileThreshold=1 -XX:-TieredCompilation TestToString
> 
> Without setbc (average): 0.1178 seconds
> With setbc (average): 0.0396 seconds

This pull request has now been integrated.

Changeset: c3717826
Author:    Jose Ricardo Ziviani <joserz at linux.ibm.com>
Committer: Martin Doerr <mdoerr at openjdk.org>
URL:       https://git.openjdk.java.net/jdk/commit/c3717826
Stats:     180 lines in 7 files changed: 62 ins; 94 del; 24 mod

8255553: [PPC64] Introduce and use setbc and setnbc P10 instructions

Reviewed-by: mdoerr

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PR: https://git.openjdk.java.net/jdk/pull/907