Wei Wang f51eca20cf [IndirectCallPromotion] Proper canonicalize coroutine function (#175606) ...

Fix an issue where coroutine function and its await suspend wrappers are
all canonicalized to the same name. This creates duplicate entries in
`MD5FuncMap` (a sorted vector) and may return an incorrect GUID that
mismatches the one from prof metadata and miss ICP. For example, coro
function `foo` and its wrappers `foo.__await_suspend_wrapper__init`,
`foo.__await_suspend_wrapper__final` are all canonicalized to `foo`.
During GUID lookup, any of them can be returned due to unstable sort.
This is more of the reliability issue (the indeterminism) than a
performance issue because hot indirect calls should've been promoted in
sample loader pass.

This also fixes the same naming issue in `CGProfile` where symtab is
created. By the time the pass is run, wrapper functions should already
be inlined but naming collision can happen to the coro function and its
post-split clones (`foo.resume`, `foo.cleanup`).

This change
* Unifies `InstrProfSymtab::getCanonicalName` with
`FunctionSamples::getCanonicalFnName` by providing a customized list of
suffixes to remove instead of removing everything after the first dot
(.) except ".__uniq.". This also addresses the "FIXME" comment.
* Uses stable sort when storing `MD5FuncMap` which avoids indeterminism
during GUID lookup. `MD5FuncMap` can still contain duplicate entries
even with this change, because no check is done before insertion. Making
entries unique needs some additional work.
* Checks for same PGO names before calling the second `addFuncWithName`,
which does nothing in case of name match.

2026-01-13 23:18:45 -08:00

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