RFR: 8272563: Possible assertion failure in CardTableBarrierSetC1

[Fairoz Matte]

This patch is proposed by the submitter of the bug - ugawa at ci.i.u-tokyo.ac.jp

The method CardTableBarrierSetC1::post_barrier generates a move LIR when TwoOperandLIRForm flag is true to move the address to be marked in the card table to a temporary register.
> __ move(addr, tmp);
However, this code only guarantees that `addr` is a valid register for LIR, which can be a virtual register. If the virtual register for `addr` is spilled to the stack by chance, the `move(addr, tmp)` is compiled to a memory-to-register which causes an assertion failure because a memory-to-register move requires their arguments to have the same size. 
The fix is to check if it is is_oop() and call the mov appropriately.

No issues found in local testing and Mach5 tier1-3

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

Commit messages:
 - 8272563: Possible assertion failure in CardTableBarrierSetC1

Changes: https://git.openjdk.java.net/jdk/pull/5164/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=5164&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8272563
  Stats: 7 lines in 1 file changed: 6 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/5164.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/5164/head:pull/5164

PR: https://git.openjdk.java.net/jdk/pull/5164