RFR: 8339132: Make DirectCodeBuilder write through without allocating instruction objects [v2]

[Chen Liang]

> Make `DirectCodeBuilder` write instructions actually directly without allocating extra objects. This speed up a lot of simple Class-File building cases that never go through intermediate transforms.

Chen Liang has updated the pull request incrementally with one additional commit since the last revision:

  Use uppercase L for long literals
  
  Co-authored-by: Andrey Turbanov <turbanoff at gmail.com>

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Changes:
  - all: https://git.openjdk.org/jdk/pull/20738/files
  - new: https://git.openjdk.org/jdk/pull/20738/files/2a3b2cf6..d798b302

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=20738&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=20738&range=00-01

  Stats: 3 lines in 1 file changed: 0 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/20738.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/20738/head:pull/20738

PR: https://git.openjdk.org/jdk/pull/20738