[jdk25u-dev] RFR: 8360271: String.indexOf intrinsics fail with +EnableX86ECoreOpts and -CompactStrings

[Aleksey Shipilev]

Same as for JDK 26, fixes the regression in JDK 24.

Additional testing:
 - [x] Linux x86_64 server fastdebug, new test case fails without the patch, passes with it
 - [ ]  Linux x86_64 server fastdebug, `tier1` with `-XX:-CompactStrings`

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Commit messages:
 - Backport 1d889b92bde5dfcb1fbe6cddb389a77f92eb1ce7

Changes: https://git.openjdk.org/jdk25u-dev/pull/165/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk25u-dev&pr=165&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8360271
  Stats: 19 lines in 2 files changed: 11 ins; 0 del; 8 mod
  Patch: https://git.openjdk.org/jdk25u-dev/pull/165.diff
  Fetch: git fetch https://git.openjdk.org/jdk25u-dev.git pull/165/head:pull/165

PR: https://git.openjdk.org/jdk25u-dev/pull/165