SymbolStringPoolEntryUnsafe provides unsafe access to SymbolStringPtr objects,
allowing clients to manually retain and release pool entries, or consume or
create SymbolStringPtr instances without affecting an entry's ref-count. This
can be useful when writing C APIs that need to handle SymbolStringPtrs.
As part of this patch the LLVM-C API implementation is updated to use the new
utility, rather than the old, private OrcV2CAPIHelper utility.
A follow-up to https://reviews.llvm.org/D142314:
* Make SymbolStringPtrs constructible from NonOwningSymbolStringPtrs.
* Move and rename getRefCount and isValid (now poolEntryIsAlive) to improve
readability. Also updates these routines to make them safe for use with
sentinel values (null, empty, tombstone).
* Move ref-counting operations into their own incRef and decRef methods.
Introduces a non-owning SymbolStringPool entry pointer. Instances of the new
type can be compared with SymbolStringPtr instances, but do not participate in
ref-counting and are therefore cheaper to copy. This makes it efficient to use
in algorithms that use symbol-strings as ids, e.g. ORC's waiting-on graph. A
future commit will rewrite ORC's waiting-on graph.
Reviewed By: dblaikie
Differential Revision: https://reviews.llvm.org/D142314
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
comparison of symbol names.
SymbolStringPool is a thread-safe string pool that will be used in upcoming Orc
APIs to facilitate efficient storage and fast comparison of symbol name strings.
llvm-svn: 319839
