Currently this is an LLVM extension to the COFF spec which is
experimental and intended to speed up linking. For now it is
behind a hidden cl::opt flag, but in the future we can move it
to a "real" cc1 flag and have the driver pass it through whenever
it is appropriate.
The patch to actually make use of this section in lld will come
in a followup.
Differential Revision: https://reviews.llvm.org/D40917
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@320649 91177308-0d34-0410-b5e6-96231b3b80d8
The motivation behind this patch is that future directions require us to
be able to compute the hash value of records independently of actually
using them for de-duplication.
The current structure of TypeSerializer / TypeTableBuilder being a
single entry point that takes an unserialized type record, and then
hashes and de-duplicates it is not flexible enough to allow this.
At the same time, the existing TypeSerializer is already extremely
complex for this very reason -- it tries to be too many things. In
addition to serializing, hashing, and de-duplicating, ti also supports
splitting up field list records and adding continuations. All of this
functionality crammed into this one class makes it very complicated to
work with and hard to maintain.
To solve all of these problems, I've re-written everything from scratch
and split the functionality into separate pieces that can easily be
reused. The end result is that one class TypeSerializer is turned into 3
new classes SimpleTypeSerializer, ContinuationRecordBuilder, and
TypeTableBuilder, each of which in isolation is simple and
straightforward.
A quick summary of these new classes and their responsibilities are:
- SimpleTypeSerializer : Turns a non-FieldList leaf type into a series of
bytes. Does not do any hashing. Every time you call it, it will
re-serialize and return bytes again. The same instance can be re-used
over and over to avoid re-allocations, and in exchange for this
optimization the bytes returned by the serializer only live until the
caller attempts to serialize a new record.
- ContinuationRecordBuilder : Turns a FieldList-like record into a series
of fragments. Does not do any hashing. Like SimpleTypeSerializer,
returns references to privately owned bytes, so the storage is
invalidated as soon as the caller tries to re-use the instance. Works
equally well for LF_FIELDLIST as it does for LF_METHODLIST, solving a
long-standing theoretical limitation of the previous implementation.
- TypeTableBuilder : Accepts sequences of bytes that the user has already
serialized, and inserts them by de-duplicating with a hash table. For
the sake of convenience and efficiency, this class internally stores a
SimpleTypeSerializer so that it can accept unserialized records. The
same is not true of ContinuationRecordBuilder. The user is required to
create their own instance of ContinuationRecordBuilder.
Differential Revision: https://reviews.llvm.org/D40518
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@319198 91177308-0d34-0410-b5e6-96231b3b80d8
Previously we were writing an empty globals stream. Windows
tools interpret this as "private symbols are not present in
this PDB", even when they are, so we need to fix this. Regardless,
without it we don't have information about global variables, so
we need to fix it anyway. This patch does that.
With this patch, the "lm" command in WinDbg correctly reports
that we have private symbols available, but the "dv" command
still refuses to display local variables.
Differential Revision: https://reviews.llvm.org/D36535
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@310743 91177308-0d34-0410-b5e6-96231b3b80d8
Merge the functionality into the random access type collection.
This class was only being used in 2 places, so getting rid of it
simplifies the code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305653 91177308-0d34-0410-b5e6-96231b3b80d8
Suppose we had a type index offsets array with a boundary at type index
N. Then you request the name of the type with index N+1, and that name
requires the name of index N-1 (think a parameter list, for example). We
didn't handle this, and we would print something like (<unknown UDT>,
<unknown UDT>).
The fix for this is not entirely trivial, and speaks to a larger
problem. I think we need to kill TypeDatabase, or at the very least kill
TypeDatabaseVisitor. We need a thing that doesn't do any caching
whatsoever, just given a type index it can compute the type name "the
slow way". The reason for the bug is that we don't have anything like
that. Everything goes through the type database, and if we've visited a
record, then we're "done". It doesn't know how to do the expensive thing
of re-visiting dependent records if they've not yet been visited.
What I've done here is more or less copied the code (albeit greatly
simplified) from TypeDatabaseVisitor, but wrapped it in an interface
that just returns a std::string. The logic of caching the name is now in
LazyRandomTypeCollection. Eventually I'd like to move the record
database here as well and the visited record bitfield here as well, at
which point we can actually just delete TypeDatabase. I don't see any
reason for it if a "sequential" collection is just a special case of a
random access collection with an empty partial offsets array.
Differential Revision: https://reviews.llvm.org/D34297
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305612 91177308-0d34-0410-b5e6-96231b3b80d8
This was originally reverted because of some non-deterministic
failures on certain buildbots. Luckily ASAN eventually caught
this as a stack-use-after-scope, so the fix is included in
this patch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305393 91177308-0d34-0410-b5e6-96231b3b80d8
This is causing failures on linux bots with an invalid stream
read. It doesn't repro in any configuration on Windows, so
reverting until I have a chance to investigate on Linux.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305371 91177308-0d34-0410-b5e6-96231b3b80d8
This allows us to use yaml2obj and obj2yaml to round-trip CodeView
symbol and type information without having to manually specify the bytes
of the section. This makes for much easier to maintain tests. See the
tests under lld/COFF in this patch for example. Before they just said
SectionData: <blob> whereas now we can use meaningful record
descriptions. Note that it still supports the SectionData yaml field,
which could be useful for initializing a section to invalid bytes for
testing, for example.
Differential Revision: https://reviews.llvm.org/D34127
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305366 91177308-0d34-0410-b5e6-96231b3b80d8
While it's not entirely clear why a compiler or linker might
put this information into an object or PDB file, one has been
spotted in the wild which was causing llvm-pdbdump to crash.
This patch adds support for reading-writing these sections.
Since I don't know how to get one of the native tools to
generate this kind of debug info, the only test here is one
in which we feed YAML into the tool to produce a PDB and
then spit out YAML from the resulting PDB and make sure that
it matches.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@304738 91177308-0d34-0410-b5e6-96231b3b80d8
This adds implementations for Symbols and FrameData, and renames
the existing codeview::StringTable class to conform to the
DebugSectionStringTable convention.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@304222 91177308-0d34-0410-b5e6-96231b3b80d8
Merging two type streams is one of the most time consuming
parts of generating a PDB, and as such it needs to be as
fast as possible. The visitor abstractions used for interoperating
nicely with many different types of inputs and outputs have
been used widely and help greatly for testability and implementing
tools, but the abstractions build up and get in the way of
performance.
This patch removes all of the visitation stuff from the type
stream merger, essentially re-inventing the leaf / member switch
and loop, but at a very low level. This allows us many other
optimizations, such as not actually deserializing *any* records
(even member records which don't describe their own length), as
the operation of "figure out how long this record is" is somewhat
faster than "figure out how long this record *and* get all its
fields out". Furthermore, whereas before we had to deserialize,
re-write type indices, then re-serialize, now we don't have to
do any of those 3 steps. We just find out where the type indices
are and pull them directly out of the byte stream and re-write
them.
This is worth a 50-60% performance increase. On top of all other
optimizations that have been applied this week, I now get the
following numbers when linking lld.exe and lld.pdb
MSVC: 25.67s
Before This Patch: 18.59s
After This Patch: 8.92s
So this is a huge performance win.
Differential Revision: https://reviews.llvm.org/D33564
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303935 91177308-0d34-0410-b5e6-96231b3b80d8
This was originally reverted because it was a breaking a bunch
of bots and the breakage was not surfacing on Windows. After much
head-scratching this was ultimately traced back to a bug in the
lit test runner related to its pipe handling. Now that the bug
in lit is fixed, Windows correctly reports these test failures,
and as such I have finally (hopefully) fixed all of them in this
patch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303446 91177308-0d34-0410-b5e6-96231b3b80d8
This is a squash of ~5 reverts of, well, pretty much everything
I did today. Something is seriously broken with lit on Windows
right now, and as a result assertions that fire in tests are
triggering failures. I've been breaking non-Windows bots all
day which has seriously confused me because all my tests have
been passing, and after running lit with -a to view the output
even on successful runs, I find out that the tool is crashing
and yet lit is still reporting it as a success!
At this point I don't even know where to start, so rather than
leave the tree broken for who knows how long, I will get this
back to green, and then once lit is fixed on Windows, hopefully
hopefully fix the remaining set of problems for real.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303409 91177308-0d34-0410-b5e6-96231b3b80d8
Right now we have multiple notions of things that represent collections of
types. Most commonly used are TypeDatabase, which is supposed to keep
mappings from TypeIndex to type name when reading a type stream, which
happens when reading PDBs. And also TypeTableBuilder, which is used to
build up a collection of types dynamically which we will later serialize
(i.e. when writing PDBs).
But often you just want to do some operation on a collection of types, and
you may want to do the same operation on any kind of collection. For
example, you might want to merge two TypeTableBuilders or you might want
to merge two type streams that you loaded from various files.
This dichotomy between reading and writing is responsible for a lot of the
existing code duplication and overlapping responsibilities in the existing
CodeView library classes. For example, after building up a
TypeTableBuilder with a bunch of type records, if we want to dump it we
have to re-invent a bunch of extra glue because our dumper takes a
TypeDatabase or a CVTypeArray, which are both incompatible with
TypeTableBuilder.
This patch introduces an abstract base class called TypeCollection which
is shared between the various type collection like things. Wherever we
previously stored a TypeDatabase& in some common class, we now store a
TypeCollection&.
The advantage of this is that all the details of how the collection are
implemented, such as lazy deserialization of partial type streams, is
completely transparent and you can just treat any collection of types the
same regardless of where it came from.
Differential Revision: https://reviews.llvm.org/D33293
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This adds a visitor that is capable of accessing type
records randomly and caching intermediate results that it
learns about during partial linear scans. This yields
amortized O(1) access to a type stream even though type
streams cannot normally be indexed.
Differential Revision: https://reviews.llvm.org/D33009
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@302936 91177308-0d34-0410-b5e6-96231b3b80d8
This was reverted due to a "missing" file, but in reality
what happened was that I renamed a file, and then due to
a merge conflict both the old file and the new file got
added to the repository. This led to an unused cpp file
being in the repo and not referenced by any CMakeLists.txt
but #including a .h file that wasn't in the repo. In an
even more unfortunate coincidence, CMake didn't report the
unused cpp file because it was in a subdirectory of the
folder with the CMakeLists.txt, and not in the same directory
as any CMakeLists.txt.
The presence of the unused file was then breaking certain
tools that determine file lists by globbing rather than
by what's specified in CMakeLists.txt
In any case, the fix is to just remove the unused file from
the patch set.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@302042 91177308-0d34-0410-b5e6-96231b3b80d8
The patch is failing to add StringTableStreamBuilder.h, but that isn't
even discovered because the corresponding StringTableStreamBuilder.cpp
isn't added to any CMakeLists.txt file and thus never built. I think
this patch is just incomplete.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@302002 91177308-0d34-0410-b5e6-96231b3b80d8
Previously we had knowledge of how to serialize and deserialize
a string table inside of DebugInfo/PDB, but the string table
that it serializes contains a piece that is actually considered
CodeView and can appear outside of a PDB. We already have logic
in llvm-readobj and MCCodeView to read and write this format,
so it doesn't make sense to duplicate the logic in DebugInfoPDB
as well.
This patch makes codeview::StringTable (for writing) and
codeview::StringTableRef (for reading), updates DebugInfoPDB
to use these classes for its own writing, and updates llvm-readobj
to additionally use StringTableRef for reading.
It's a bit more difficult to get MCCodeView to use this for
writing, but it's a logical next step.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301986 91177308-0d34-0410-b5e6-96231b3b80d8
Previously we wrote line information and file checksum
information, but we did not write information about inlinee
lines and functions. This patch adds support for that.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301936 91177308-0d34-0410-b5e6-96231b3b80d8
Previously parsing of these were all grouped together into a
single master class that could parse any type of debug info
fragment.
With writing forthcoming, the complexity of each individual
fragment is enough to warrant them having their own classes so
that reading and writing of each fragment type can be grouped
together, but isolated from the code for reading and writing
other fragment types.
In doing so, I found a place where parsing code was duplicated
for the FileChecksums fragment, across llvm-readobj and the
CodeView library, and one of the implementations had a bug.
Now that the codepaths are merged, the bug is resolved.
Differential Revision: https://reviews.llvm.org/D32547
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301557 91177308-0d34-0410-b5e6-96231b3b80d8
We have a lot of very similarly named classes related to
dealing with module debug info. This patch has NFC, it just
renames some classes to be more descriptive (albeit slightly
more to type). The mapping from old to new class names is as
follows:
Old | New
ModInfo | DbiModuleDescriptor
ModuleSubstream | ModuleDebugFragment
ModStream | ModuleDebugStream
With the corresponding Builder classes renamed accordingly.
Differential Revision: https://reviews.llvm.org/D32506
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301555 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This removes the 'remapTypeIndices' method on every TypeRecord class. My
original idea was that this would be the beginning of some kind of
generic entry point that would enumerate all of the TypeIndices inside
of a TypeRecord, so that we could write generic graph algorithms for
them without duplicating the knowledge of which fields are type index
fields everywhere. This never happened, and nothing else uses this
method. I need to change the API to deal with merging into IPI streams,
so let's move it into the file that uses it first.
Reviewers: zturner, ruiu
Reviewed By: zturner, ruiu
Subscribers: mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D31267
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298564 91177308-0d34-0410-b5e6-96231b3b80d8
Previously we could round-trip type records from PDB -> Yaml ->
PDB, but for symbols we could only go from PDB -> Yaml. This
completes the round-tripping for symbols as well.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@297625 91177308-0d34-0410-b5e6-96231b3b80d8
Previously the type dumper itself was passed around to a lot of different
places and manipulated in ways that were more appropriate on the type
database. For example, the entire TypeDumper was passed into the symbol
dumper, when all the symbol dumper wanted to do was lookup the name of a
TypeIndex so it could print it. That's what the TypeDatabase is for --
mapping type indices to names.
Another example is how if the user runs llvm-pdbdump with the option to
dump symbols but not types, we still have to visit all types so that we
can print minimal information about the type of a symbol, but just without
dumping full symbol records. The way we did this before is by hacking it
up so that we run everything through the type dumper with a null printer,
so that the output goes to /dev/null. But really, we don't need to dump
anything, all we want to do is build the type database. Since
TypeDatabaseVisitor now exists independently of TypeDumper, we can do
this. We just build a custom visitor callback pipeline that includes a
database visitor but not a dumper.
All the hackery around printers etc goes away. After this patch, we could
probably even delete the entire CVTypeDumper class since really all it is
at this point is a thin wrapper that hides the details of how to build a
useful visitation pipeline. It's not a priority though, so CVTypeDumper
remains for now.
After this patch we will be able to easily plug in a different style of
type dumper by only implementing the proper visitation methods to dump
one-line output and then sticking it on the pipeline.
Differential Revision: https://reviews.llvm.org/D28524
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291724 91177308-0d34-0410-b5e6-96231b3b80d8
We were starting to get some name clashes between llvm-pdbdump
and the common CodeView framework, so I took this opportunity
to rename a bunch of files to more accurately describe their
usage. This also helps in llvm-pdbdump to distinguish
between different files and whether they are used for pretty
dump mode or raw dump mode.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291627 91177308-0d34-0410-b5e6-96231b3b80d8
This creates a centralized class in which to store type records.
It stores types as an array of entries, which matches the
notion of a type stream being a topologically sorted DAG.
Logic to build up such a database was already being used in
CVTypeDumper, so CVTypeDumper is now updated to to read from
a TypeDatabase which is filled out by an earlier visitor in
the pipeline.
Differential Revision: https://reviews.llvm.org/D28486
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The original patch was broken due to some undefined behavior
as well as warnings that were triggering -Werror.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@290000 91177308-0d34-0410-b5e6-96231b3b80d8
Previously support had been added for using CodeViewRecordIO
to read (deserialize) CodeView type records. This patch adds
support for writing those same records. With this patch,
reading and writing of CodeView type records finally uses a single
codepath.
Differential Revision: https://reviews.llvm.org/D26253
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@286304 91177308-0d34-0410-b5e6-96231b3b80d8
Using a pattern similar to that of YamlIO, this allows
us to have a single codepath for translating codeview
records to and from serialized byte streams. The
current patch only hooks this up to the reading of
CodeView type records. A subsequent patch will hook
it up for writing of CodeView type records, and then a
third patch will hook up the reading and writing of
CodeView symbols.
Differential Revision: https://reviews.llvm.org/D26040
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@285836 91177308-0d34-0410-b5e6-96231b3b80d8
Type visitor code had already been refactored previously to
decouple the visitor and the visitor callback interface. This
was necessary for having the flexibility to visit in different
ways (for example, dumping to yaml, reading from yaml, dumping
to ScopedPrinter, etc).
This patch merely implements the same visitation pattern for
symbol records that has already been implemented for type records.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@283609 91177308-0d34-0410-b5e6-96231b3b80d8
Until now, our use case for the visitor has been to take a stream of bytes
representing a type stream, deserialize the records in sequence, and do
something with them, where "something" is determined by how the user
implements a particular set of callbacks on an abstract class.
For actually writing PDBs, however, we want to do the reverse. We have
some kind of description of the list of records in their in-memory format,
and we want to process each one. Perhaps by serializing them to a byte
stream, or perhaps by converting them from one description format (Yaml)
to another (in-memory representation).
This was difficult in the current model because deserialization and
invoking the callbacks were tightly coupled.
With this patch we change this so that TypeDeserializer is itself an
implementation of the particular set of callbacks. This decouples
deserialization from the iteration over a list of records and invocation
of the callbacks. TypeDeserializer is initialized with another
implementation of the callback interface, so that upon deserialization it
can pass the deserialized record through to the next set of callbacks. In
a sense this is like an implementation of the Decorator design pattern,
where the Deserializer is a decorator.
This will be useful for writing Pdbs from yaml, where we have a
description of the type records in Yaml format. In this case, the visitor
implementation would have each visitation callback method implemented in
such a way as to extract the proper set of fields from the Yaml, and it
could maintain state that builds up a list of these records. Finally at
the end we can pass this information through to another set of callbacks
which serializes them into a byte stream.
Reviewed By: majnemer, ruiu, rnk
Differential Revision: https://reviews.llvm.org/D23177
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@277871 91177308-0d34-0410-b5e6-96231b3b80d8
This provides a better layering of responsibilities among different
aspects of PDB writing code. Some of the MSF related code was
contained in CodeView, and some was in PDB prior to this. Further,
we were often saying PDB when we meant MSF, and the two are
actually independent of each other since in theory you can have
other types of data besides PDB data in an MSF. So, this patch
separates the MSF specific code into its own library, with no
dependencies on anything else, and DebugInfoCodeView and
DebugInfoPDB take dependencies on DebugInfoMsf.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@276458 91177308-0d34-0410-b5e6-96231b3b80d8
There was a regression introduced during type stream merging when
visiting a field list record. This has been fixed in this patch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@272929 91177308-0d34-0410-b5e6-96231b3b80d8
This allows better catching of compiler errors since we can use
the override keyword to verify that methods are actually
overridden.
Also in this patch I've changed from storing a boolean Error
code everywhere to returning an llvm::Error, to propagate richer
error information up the call stack.
Reviewed By: ruiu, rnk
Differential Revision: http://reviews.llvm.org/D21410
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@272926 91177308-0d34-0410-b5e6-96231b3b80d8
This adds method and tests for writing to a PDB stream. With
this, even a PDB stream which is discontiguous can be treated
as a sequential stream of bytes for the purposes of writing.
Reviewed By: ruiu
Differential Revision: http://reviews.llvm.org/D21157
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@272369 91177308-0d34-0410-b5e6-96231b3b80d8
To facilitate this, a couple of changes had to be made:
1. `ModuleSubstream` got moved from `DebugInfo/PDB` to
`DebugInfo/CodeView`, and various codeview related types are defined
there. It turns out `DebugInfo/CodeView/Line.h` already defines many of
these structures, but this is really old code that is not endian aware,
doesn't interact well with `StreamInterface` and not very helpful for
getting stuff out of a PDB. Eventually we should migrate the old readobj
`COFFDumper` code to these new structures, or at least merge their
functionality somehow.
2. A `ModuleSubstream` visitor is introduced. Depending on where your
module substream array comes from, different subsets of record types can
be expected. We are already hand parsing these substream arrays in many
places especially in `COFFDumper.cpp`. In the future we can migrate these
paths to the visitor as well, which should reduce a lot of code in
`COFFDumper.cpp`.
Differential Revision: http://reviews.llvm.org/D20936
Reviewed By: ruiu, majnemer
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@271621 91177308-0d34-0410-b5e6-96231b3b80d8
We have need to reuse this functionality, including making
additional generic stream types that are smarter about how and
when they copy memory versus referencing the original memory.
So all of these structures belong in the common library
rather than being pdb specific.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@270751 91177308-0d34-0410-b5e6-96231b3b80d8
