[Function] Lock the function when parsing call site info #1436
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Summary:
DWARF-parsing methods in SymbolFileDWARF which update module state
typically take the module lock. ParseCallEdgesInFunction doesn't do
this, but higher-level locking within lldb::Function (which owns the
storage for parsed call edges) is necessary.
The lack of locking could explain some as-of-yet unreproducible crashes
which occur in Function::GetTailCallingEdges(). In these crashes, the
m_call_edgesvector is non-empty but contains a nullptr, whichshouldn't be possible. (If this vector is non-empty, it must contain a
non-null unique_ptr.)
This may address rdar://55622443 and rdar://65119458.
Reviewers: jasonmolenda, friss, jingham
Subscribers: aprantl, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D83359
(cherry picked from commit 6cfc90b)