[memprof] Undrift MemProf profile even when some frames are missing (#120500) This patch makes the MemProf undrifting process a little more lenient. Consider an inlined call hierarchy: foo -> bar -> ::new If bar tail-calls ::new, the profile appears to indicate that foo directly calls ::new. This is a problem because the perceived call hierarchy in the profile looks different from what we can obtain from the inline stack in the IR. Recall that undrifting works by constructing and comparing a list of direct calls from the profile and that from the IR. This patch modifies the construction of the latter. Specifically, if foo calls bar in the IR, but bar is missing the profile, we pretend that foo directly calls some heap allocation function. We apply this transformation only in the inline stack leading to some heap allocation function.
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