hg: jdk/jdk: 8209783: AArch64: Combine Multiply and Neg operations in C2

[adinn at redhat.com]

Changeset: 25048be67f4a
Author:    adinn
Date:      2018-08-22 16:06 +0100
URL:       http://hg.openjdk.java.net/jdk/jdk/rev/25048be67f4a

8209783: AArch64: Combine Multiply and Neg operations in C2
Summary: Generate mneg instructions for a*(-b) or (-a)*b to save one instruction
Reviewed-by: adinn
Contributed-by: pengfei.li at arm.com

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