AliasAnalysis: check for immutable scopes. #37473
Merged
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If the "regular" alias analysis thinks that an instruction may write to an address, check if the instruction is in an immutable scope of
V
.That means that even if we don't know anything about the instruction (e.g. a call to an unknown function), we can be sure that it cannot write to the address.
An immutable scope is for example a read-only begin_access/end_access scope.
Another example is a borrow scope of an immutable copy-on-write buffer, for example: