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Commit 2b09d672 authored by Amir Ayupov's avatar Amir Ayupov Committed by Maksim Panchenko
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Conservatively handle jump tables in split functions

Summary:
- Allow jump table entries to point to locations inside the function and its fragments.
Reasoning behind this is that jump table identification has the logic of stopping at entry which belongs to a function different from the one originally referencing jump table. This assumption is invalid for jump tables with entries pointing to both parent function and cold fragments, leading to "unclaimed PC-relative relocations" assertion.

- Add fragment identification heuristic based on function name regex and contiguous jump table entries.
Currently, parent-to-fragment relationship is set up based on interprocedural references – direct references from the parent function. These references don't include references through jump table.
Additionally, some fragments are only reachable through jump table. In that case, in order to fully consume jump table, add parent-to-fragment relationship during `analyzeJumpTable` using the following heuristics:
  1. Fragment is identified as such based on name (contains `.cold.` part), but
  2. Parent function is not set – no direct interprocedural references to that fragment, and
  3. Fragment has the name of the form <parent>.cold(.\d+)

* For split functions with jump table entries spanning parent and fragments, mark parent and all fragments as ignored.

(cherry picked from FBD24456904)
parent dc48354f
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