RFR: 8224090: [PPC64] Fix SLP patterns for filling an array with double float literals

[Kazunori Ogata]

Hi,

May I get review for a webrev to fix SLP patterns that use PPC64 VSX 
instructions?

We found that SLP patterns added by JDK-8208171 [1] use incorrect data 
type, so the patterns have never been used. Further, the pattern for 
filling -1.0 is confused with the operation for filling -1L. 

This webrev fixes the pattern to fill an array with 0 to use 0.0d instead 
of 0d, and removes the pattern to will with -1 because the bit pattern of 
-1.0d is not easy to generate using a single VSX instruction.  It's should 
be better to load the literal from TOC and use general repl2D_reg_Ex 
pattern.

I also fixed some comments in "format %{ ... %}" to show correct matching 
types.


Bug: https://bugs.openjdk.java.net/browse/JDK-8224090

Webrev: http://cr.openjdk.java.net/~horii/8224090/webrev.00/

Ref:
[1] https://bugs.openjdk.java.net/browse/JDK-8208171


Regards,
Ogata