Hi,

This patch adds non-relative jump table support on Power Linux. It 
implements ASM_OUTPUT_ADDR_VEC_ELT and adds four new expansions for 
non-relative jump table in rs6000.md. It also defines a rs6000 
option(mrelative-jumptables). If it's set to false, the non-relative 
jump table is picked up even PIC flag is set.

The attachments are the patch diff file and change log file.

Bootstrapped and tested on powerpc64le-linux-gnu with no regressions.  
Is this okay for trunk? Any recommendations? Thanks a lot.