David added the JamCRC implementation in r246590. More recently, Eugene
added a CRC-32 implementation in r357901, which falls back to zlib's
crc32 function if present.
These checksums are essentially the same, so having multiple
implementations seems unnecessary. This replaces the CRC-32
implementation with the simpler one from JamCRC, and implements the
JamCRC interface in terms of CRC-32 since this means it can use zlib's
implementation when available, saving a few bytes and potentially making
it faster.
JamCRC took an ArrayRef<char> argument, and CRC-32 took a StringRef.
This patch changes it to ArrayRef<uint8_t> which I think is the best
choice, and simplifies a few of the callers nicely.
Differential revision: https://reviews.llvm.org/D68570
llvm-svn: 374148
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
Some records point to an LF_CLASS, LF_UNION, LF_STRUCTURE, or LF_ENUM
which is a forward reference and doesn't contain complete debug
information. In these cases, we'd like to be able to quickly locate the
full record. The TPI stream stores an array of pre-computed record hash
values, one for each type record. If we pre-process this on startup, we
can build a mapping from hash value -> {list of possible matching type
indices}. Since hashes of full records are only based on the name and or
unique name and not the full record contents, we can then use forward
ref record to compute the hash of what *would* be the full record by
just hashing the name, use this to get the list of possible matches, and
iterate those looking for a match on name or unique name.
llvm-pdbutil is updated to resolve forward references for the purposes
of testing (plus it's just useful).
Differential Revision: https://reviews.llvm.org/D52283
llvm-svn: 342656
Summary:
This removes the CVTypeVisitor updater and verifier classes. They were
made dead by the minimal type dumping refactoring. Replace them with a
single function that takes a type record and produces a hash. Call this
from the minimal type dumper and compare the hash.
I also noticed that the microsoft-pdb reference repository uses a basic
CRC32 for records that aren't special. We already have an implementation
of that CRC ready to use, because it's used in COFF for ICF.
I'll make LLD call this hashing utility in a follow-up change. We might
also consider using this same hash in type stream merging, so that we
don't have to hash our records twice.
Reviewers: inglorion, ruiu
Subscribers: llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D35515
llvm-svn: 308240
Bill Wendling