hg: jdk/hs: 8190869: C2: missing strength reduction of Math.pow(x, 2.0D) to x*x

[vladimir.x.ivanov at oracle.com]

Changeset: 3c9975e46464
Author:    vlivanov
Date:      2017-12-13 19:32 +0300
URL:       http://hg.openjdk.java.net/jdk/hs/rev/3c9975e46464

8190869: C2: missing strength reduction of Math.pow(x, 2.0D) to x*x
Reviewed-by: kvn

! src/hotspot/cpu/x86/macroAssembler_x86_pow.cpp
! src/hotspot/share/opto/library_call.cpp