Revert "[regalloc] Introduce deferred fixed ranges"

This reverts commit b176931311c49597e312056109abfa45e31ea4a2.

Reason for revert: Flag access breaks TSAN (not an issue with this
CL as such, but we need to revert to re-open the tree).

Original change's description:
> [regalloc] Introduce deferred fixed ranges
> Fixed ranges are used to express register constraints in the
> allocator. This change splits these fixed ranges into one for
> normal code and deferred code. The former are handeled as before
> whereas the latter are only made visible while allocating
> registers for deferred code.
> This prevents forward looking decisions in normal code to be
> impacted by register constraints from deferred code.
> Change-Id: I67d562bb41166194e62765d5ab051bc961054fc7
> Reviewed-on:
> Commit-Queue: Sigurd Schneider <>
> Reviewed-by: Jaroslav Sevcik <>
> Reviewed-by: Sigurd Schneider <>
> Cr-Commit-Position: refs/heads/master@{#60322},,

Change-Id: I5675a96acf0b5e5f7d63c60a742d2971b6d0d34d
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-by: Leszek Swirski <>
Commit-Queue: Leszek Swirski <>
Cr-Commit-Position: refs/heads/master@{#60324}
5 files changed
tree: 5bc2c7c3a0eb79af5136f6bf40150b277ba2003e
  1. .clang-format
  2. .clang-tidy
  3. .editorconfig
  4. .git-blame-ignore-revs
  5. .gitattributes
  6. .gitignore
  7. .gn
  8. .vpython
  13. ChangeLog
  14. DEPS
  16. LICENSE.fdlibm
  17. LICENSE.strongtalk
  18. LICENSE.v8
  19. LICENSE.valgrind
  20. OWNERS
  24. benchmarks/
  25. build_overrides/
  26. codereview.settings
  27. custom_deps/
  28. docs/
  29. gni/
  30. include/
  31. infra/
  32. samples/
  33. snapshot_toolchain.gni
  34. src/
  35. test/
  36. testing/
  37. third_party/
  38. tools/

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