RFR: 8256956: RegisterImpl::max_slots_per_register is incorrect on AMD64 [v2]

[Jie Fu]

> Hi all,
> 
> The bug was found while I was learning @iwanowww 's patch [1].
> 
> As we know, the slot-size is 32-bit and the registers are 64-bit on AMD64.
> So RegisterImpl::max_slots_per_register [2] should be 2 on AMD64.
> 
> It would be better to fix it.
> 
> Testing:
>   - tier1~3 on Linux/x64
> 
> Thanks.
> Best regards,
> Jie
> 
> [1] https://github.com/openjdk/jdk/pull/1132
> [2] https://github.com/openjdk/jdk/blob/master/src/hotspot/cpu/x86/register_x86.hpp#L53

Jie Fu has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains two additional commits since the last revision:

 - Merge branch 'master' into JDK-8256956
 - 8256956: RegisterImpl::max_slots_per_register is incorrect on AMD64

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/1413/files
  - new: https://git.openjdk.java.net/jdk/pull/1413/files/915e653a..5de63d0c

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=1413&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=1413&range=00-01

  Stats: 9467 lines in 221 files changed: 2934 ins; 1175 del; 5358 mod
  Patch: https://git.openjdk.java.net/jdk/pull/1413.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/1413/head:pull/1413

PR: https://git.openjdk.java.net/jdk/pull/1413