RFR: 8280152: AArch64: Reuse runtime call trampolines in C2 [v2]

[Yi-Fan Tsai]

> A trampoline stub could be generated for each runtime call. These trampolines could be duplication if the callees are the same. This change delays the stub generation and generates one stub for a distinct callee.
> 
> Benchmark als, chi-square, dec-tree, gauss-mix, log-regression, movie-lens, naive-bayes, page-rank, fj-means, reactors, future-genetic, mnemonics, dotty, scala-kmeans, and finagle-http in Renaissance (0.14.1) are tested. The sum of the used size of CodeHeap 'non-profiled nmethods' and CodeHeap 'profiled nmethods' shows ~4.7% reduction on average.

Yi-Fan Tsai has updated the pull request incrementally with one additional commit since the last revision:

  Rename variables

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/9405/files
  - new: https://git.openjdk.org/jdk/pull/9405/files/8e0f473a..0c225a66

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=9405&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=9405&range=00-01

  Stats: 20 lines in 4 files changed: 1 ins; 1 del; 18 mod
  Patch: https://git.openjdk.org/jdk/pull/9405.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/9405/head:pull/9405

PR: https://git.openjdk.org/jdk/pull/9405