RFR: 8280089: compiler/c2/irTests/TestIRAbs.java fails on some arches

[Aleksey Shipilev]

This new test is apparently fails in GHA. 

The trouble is that AbsL parts of the test are arch-specific, as only {x86_64,aarch64,ppc64,s390}.ad have the match rules for AbsL. x86_32.ad does not have it, so C2 never actually emits AbsL in x86_32 case. AbsI, AbsF, AbsD are also not supported by arm.ad.

I wonder if IR Test Framework might be able to disable subtests based on arch... It is probably all around easier to make this test x86_64 specific. It tests shared C2 code, so testing one architecture is probably enough. 

Open for other suggestions, though.

Additional testing:
 - [x] Linux x86_64 fastdebug, test still passes
 - [x] Linux x86_32 fastdebug, test used to fail, now is skipped

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

Commit messages:
 - Fix

Changes: https://git.openjdk.java.net/jdk/pull/7116/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=7116&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8280089
  Stats: 2 lines in 1 file changed: 1 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/7116.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/7116/head:pull/7116

PR: https://git.openjdk.java.net/jdk/pull/7116