Originally we created our 64-bit UID scheme by using the first byte as
sort of a "tag" to represent what kind of symbol this was, and we
re-used the PDB_SymType enumeration for this. For native pdb support,
this is not really the right abstraction layer, because what we really
want is something that tells us *how* to find the symbol. This means,
specifically, is in the globals stream / public stream / module stream /
TPI stream / etc, and for whichever one it is in, where is it within
that stream?
A good example of why the old namespacing scheme was insufficient is
that it is more or less impossible to create a uid for a field list
member of a class/struction/union/enum that tells you how to locate
the original record.
With this new scheme, the first byte is no longer a PDB_SymType enum
but a new enum created specifically to identify where in the PDB
this record lives. This gives us much better flexibility in
what kinds of symbols the uids can identify.
llvm-svn: 347018
In order to accurately put a type into the correct location in the AST
we construct from debug info, we need to be able to determine what
DeclContext (namespace, global, nested class, etc) that it goes into.
PDB doesn't contain this mapping. It does, however, contain the reverse
mapping. That is, for a given class type T, you can determine all
classes Q1, Q2, ..., Qn that are nested inside of T. We need to know,
for a given class type Q, what type T is it nested inside of.
This patch builds this map as a pre-processing step when we first
load the PDB by scanning every type. Initial tests show that while
this can be slow in debug builds of LLDB, it is quite fast in release
builds (less than 2 seconds for a ~1GB PDB, and it only needs to happen
once).
Furthermore, having this pre-processing step in place allows us to
repurpose it for building up other kinds of indexing to it down the
line. For the time being, this gives us very accurate reconstruction
of the DeclContext hierarchy.
Differential Revision: https://reviews.llvm.org/D54216
llvm-svn: 346429
This adds basic support for getting function signature types
into LLDB's type system, including into clang's AST. There are
a few edge cases which are not correctly handled, mostly dealing
with nested classes, but this isn't specific to functions and
apply equally to variable types. Note that no attempt has been
made yet to deal with member function types, which will happen
in subsequent patches.
Differential Revision: https://reviews.llvm.org/D53951
llvm-svn: 345848
Previous patches added support for dumping global variables of
primitive types, so we now do the same for class types.
For the most part, everything just worked, there was only one
minor bug needing fixed, which was that for variables of modified
types (e.g. const, volatile, etc) we can't resolve the forward
decl in CreateAndCacheType because the PdbSymUid must point to the
LF_MODIFIER which must point to the forward decl. So when it comes
time to call CompleteType, an assert was firing because we expected
to get a class, struct, union, or enum, but we were getting an
LF_MODIFIER instead.
The other issue is that one the newly added tests is for an array
member, which was not yet supported, so we add support for that
now in this patch.
There's probably room for other interesting layout test cases
here, but this at least should test the basics.
Differential Revision: https://reviews.llvm.org/D53822
llvm-svn: 345629
This is mostly some cleanup done in the process of implementing
some basic support for types. I tried to split up the patch a
bit to get some of the NFC portion of the patch out into a separate
commit, and this is the result of that. It moves some code around,
deletes some spurious namespace qualifications, removes some
unnecessary header includes, forward declarations, etc.
llvm-svn: 344913
This was originally reverted due to some test failures on
Linux. Those problems turned out to require several additional
patches to lld and clang in order to fix, which have since been
submitted. This patch is resubmitted unchanged. All tests now
pass on both Linux and Windows.
llvm-svn: 344409
This was originally causing some test failures on non-Windows
platforms, which required fixes in the compiler and linker. After
those fixes, however, other tests started failing. Reverting
temporarily until I can address everything.
llvm-svn: 344279
The existing SymbolFilePDB only works on Windows, as it is written
against a closed-source Microsoft SDK that ships with their debugging
tools.
There are several reasons we want to bypass this and go straight to the
bits of the PDB, but just to list a few:
More room for optimization. We can't see inside the implementation of
the Microsoft SDK, so we don't always know if we're doing things in the
most efficient way possible. For example, setting a breakpoint on main
of a big program currently takes several seconds. With the
implementation here, the time is unnoticeable.
We want to be able to symbolize Windows minidumps even if not on
Windows. Someone should be able to debug Windows minidumps as if they
were on Windows, given that no running process is necessary.
This patch is a very crude first attempt at filling out some of the
basic pieces.
I've implemented FindFunctions, ParseCompileUnitLineTable, and
ResolveSymbolContext for a limited subset of possible parameter values,
which is just enough to get it to display something nice for the
breakpoint location.
I've added several tests exercising this functionality which are limited
enough to work on all platforms but still exercise this functionality.
I'll try to add as many tests of this nature as I can, but at some
point we'll need a live process.
For now, this plugin is enabled always on non-Windows, and by setting
the environment variable LLDB_USE_NATIVE_PDB_READER=1 on Windows.
Eventually, once it's at parity with the Windows implementation, we'll
delete the Windows DIA-based implementation.
Differential Revision: https://reviews.llvm.org/D53002
llvm-svn: 344154
