Integrated: 8280511: AArch64: Combine shift and negate to a single instruction

Fei Gao fgao at openjdk.java.net
Fri Apr 8 01:29:42 UTC 2022


On Tue, 15 Feb 2022 06:48:10 GMT, Fei Gao <fgao at openjdk.org> wrote:

> Hi,
> 
> In AArch64,
> 
> asr     x10, x1, #31
> neg     x0, x10
> 
> can be optimized to:
> `neg    x0, x1, asr #31`
> 
> To implement the instruction combining, we add matching rules in the backend.
> 
> Thanks.

This pull request has now been integrated.

Changeset: e572a525
Author:    Fei Gao <fgao at openjdk.org>
Committer: Ningsheng Jian <njian at openjdk.org>
URL:       https://git.openjdk.java.net/jdk/commit/e572a525f55259402a21822c4045ba5cd4726d07
Stats:     259 lines in 3 files changed: 257 ins; 0 del; 2 mod

8280511: AArch64: Combine shift and negate to a single instruction

Reviewed-by: njian, ngasson

-------------

PR: https://git.openjdk.java.net/jdk/pull/7471


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