Summary:
The FileSpec class is often used as a sort of a pattern -- one specifies
a bare file name to search, and we check if in matches the full file
name of an existing module (for example).
These comparisons used FileSpec::Equal, which had some support for it
(via the full=false argument), but it was not a good fit for this job.
For one, it did a symmetric comparison, which makes sense for a function
called "equal", but not for typical searches (when searching for
"/foo/bar.so", we don't want to find a module whose name is just
"bar.so"). This resulted in patterns like:
if (FileSpec::Equal(pattern, file, pattern.GetDirectory()))
which would request a "full" match only if the pattern really contained
a directory. This worked, but the intended behavior was very unobvious.
On top of that, a lot of the code wanted to handle the case of an
"empty" pattern, and treat it as matching everything. This resulted in
conditions like:
if (pattern && !FileSpec::Equal(pattern, file, pattern.GetDirectory())
which are nearly impossible to decipher.
This patch introduces a FileSpec::Match function, which does exactly
what most of FileSpec::Equal callers want, an asymmetric match between a
"pattern" FileSpec and a an actual FileSpec. Empty paterns match
everything, filename-only patterns match only the filename component.
I've tried to update all callers of FileSpec::Equal to use a simpler
interface. Those that hardcoded full=true have been changed to use
operator==. Those passing full=pattern.GetDirectory() have been changed
to use FileSpec::Match.
There was also a handful of places which hardcoded full=false. I've
changed these to use FileSpec::Match too. This is a slight change in
semantics, but it does not look like that was ever intended, and it was
more likely a result of a misunderstanding of the "proper" way to use
FileSpec::Equal.
[In an ideal world a "FileSpec" and a "FileSpec pattern" would be two
different types, but given how widespread FileSpec is, it is unlikely
we'll get there in one go. This at least provides a good starting point
by centralizing all matching behavior.]
Reviewers: teemperor, JDevlieghere, jdoerfert
Subscribers: emaste, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D70851
Summary:
CompileUnit is a complicated class. Having it be implicitly convertible
to a FileSpec makes reasoning about it even harder.
This patch replaces the inheritance by a simple member and an accessor
function. This avoid the need for casting in places where one needed to
force a CompileUnit to be treated as a FileSpec, and does not add much
verbosity elsewhere.
It also fixes a bug where we were wrongly comparing CompileUnit& and a
CompileUnit*, which compiled due to a combination of this inheritance
and the FileSpec*->FileSpec implicit constructor.
Reviewers: teemperor, JDevlieghere, jdoerfert
Subscribers: lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D70827
This is basically the same bug as in r260434.
SymbolFileDWARF::FindTypes has exponential worst-case when digging
through dependency DAG of .pcm files because each object file and .pcm
file may depend on an already-visited .pcm file, which may again have
dependencies. Fixed here by carrying a set of already visited
SymbolFiles around.
rdar://problem/56993424
Differential Revision: https://reviews.llvm.org/D70106
This patch removes the size_t return value and the append parameter
from the remainder of the Find.* functions in LLDB's internal API. As
in the previous patches, this is motivated by the fact that these
parameters aren't really used, and in the case of the append parameter
were frequently implemented incorrectly.
Differential Revision: https://reviews.llvm.org/D69119
llvm-svn: 375160
In r368345 I accidentally introduced a regression that would
over-report the number of matches found by FindTypes if the
DeclContext Filter was hit.
This patch simply removes the size_t return parameter altogether —
it's not that useful.
rdar://problem/55500457
Differential Revision: https://reviews.llvm.org/D68169
llvm-svn: 373344
I noticed that SymbolFileDWARFDebugMap::FindTypes was implementing it
incorrectly (passing append=false in a for-loop to recursive calls to
FindTypes would yield only the very last set of results), but instead
of fixing it, removing it seemed like an even better option.
rdar://problem/54412692
Differential Revision: https://reviews.llvm.org/D68171
llvm-svn: 373224
plugin.
Unfortunately the test is currently XFAILed because of missing changes
to the clang driver.
Differential Revision: https://reviews.llvm.org/D67124
llvm-svn: 370931
This patch is also motivated by the Swift branch and is effectively NFC for the single-TypeSystem llvm.org branch.
In multi-language projects it is extremely common to have, e.g., a
Clang type and a similarly-named rendition of that same type in
another language. When searching for a type It is much cheaper to pass
a set of supported languages to the SymbolFile than having it
materialize every result and then rejecting the materialized types
that have the wrong language.
Differential Revision: https://reviews.llvm.org/D66546
<rdar://problem/54471165>
This reapplies r369690 with a previously missing constructor for LanguageSet.
llvm-svn: 369710
Now that we've moved to C++14, we no longer need the llvm::make_unique
implementation from STLExtras.h. This patch is a mechanical replacement
of (hopefully) all the llvm::make_unique instances across the monorepo.
Differential revision: https://reviews.llvm.org/D66259
llvm-svn: 368933
Summary:
This patch removes the GetSymbolVendor function, and the various
mentions of the SymbolVendor in the Module class. The implementation of
GetSymbolVendor is "inlined" into the GetSymbolFile class which I
created earlier.
After this patch, the SymbolVendor class still exists inside the Module
object, but only as an implementation detail -- a fancy holder for the
SymbolFile. That will be removed in the next patch.
Reviewers: clayborg, JDevlieghere, jingham, jdoerfert
Subscribers: jfb, lldb-commits
Differential Revision: https://reviews.llvm.org/D65864
llvm-svn: 368263
Summary:
This patch removes the GetSymtab method from the SymbolVendor, which is
a no-op as it's implementation just forwards to the relevant SymbolFile.
Instead it creates a Module::GetSymtab, which calls the SymbolFile
method directly.
All callers have been updated to use the Module method directly instead
of a two phase GetSymbolVendor->GetSymtab search, which leads to reduced
intentation in a lot of deeply nested code.
Reviewers: clayborg, JDevlieghere, jingham
Subscribers: lldb-commits
Differential Revision: https://reviews.llvm.org/D65569
llvm-svn: 367820
Summary:
This is the next step in avoiding funneling all SymbolFile calls through
the SymbolVendor. Right now, it is just a convenience function, but it
allows us to update all calls to SymbolVendor functions to access the
SymbolFile directly. Once all call sites have been updated, we can
remove the GetSymbolVendor member function.
This patch just updates the calls to GetSymbolVendor, which were calling
it just so they could fetch the underlying symbol file. Other calls will
be done in follow-ups.
Reviewers: JDevlieghere, clayborg, jingham
Subscribers: lldb-commits
Differential Revision: https://reviews.llvm.org/D65435
llvm-svn: 367664
Summary:
This commit achieves the following:
- Functions used to return a `TypeSystem *` return an
`llvm::Expected<TypeSystem *>` now. This means that the result of a call
is always checked, forcing clients to move more carefully.
- `TypeSystemMap::GetTypeSystemForLanguage` will either return an Error or a
non-null pointer to a TypeSystem.
Reviewers: JDevlieghere, davide, compnerd
Subscribers: jdoerfert, lldb-commits
Differential Revision: https://reviews.llvm.org/D65122
llvm-svn: 367360
Summary:
Similarly to the compile unit lists, the list of types can also be
managed by the symbol file itself.
Since the only purpose of this list seems to be to maintain an owning
reference to all the types a symbol file has created (items are only
ever added to the list, never retrieved), I remove the passthrough
functions in SymbolVendor and Module. I also tighten the interface of
the function (return a reference instead of a pointer, make it protected
instead of public).
Reviewers: clayborg, JDevlieghere, jingham
Subscribers: lldb-commits
Differential Revision: https://reviews.llvm.org/D65135
llvm-svn: 366994
This patch replaces explicit calls to log::Printf with the new LLDB_LOGF
macro. The macro is similar to LLDB_LOG but supports printf-style format
strings, instead of formatv-style format strings.
So instead of writing:
if (log)
log->Printf("%s\n", str);
You'd write:
LLDB_LOG(log, "%s\n", str);
This change was done mechanically with the command below. I replaced the
spurious if-checks with vim, since I know how to do multi-line
replacements with it.
find . -type f -name '*.cpp' -exec \
sed -i '' -E 's/log->Printf\(/LLDB_LOGF\(log, /g' "{}" +
Differential revision: https://reviews.llvm.org/D65128
llvm-svn: 366936
This is part two of the change started in r359330. This patch moves the
ownership of the script interpreter from the command interpreter into
the debugger. I would've preferred to remove the lazy initialization,
however the fact that the scripting language is set after the debugger
is created makes that tricky. So for now this does exactly the same
thing as when it was under the command interpreter. The result is that
this patch is fully NFC.
Differential revision: https://reviews.llvm.org/D61211
llvm-svn: 359354
Summary:
This is a preparatory step to enable adding of unwind plans by symbol
file plugins.
Although at the surface it seems that currently symbol files have
nothing to do with unwinding, this isn't entirely correct even now. The
mere act of adding a symbol file can have the effect of making more
sections (typically .debug_frame) available to the unwinding machinery,
so that it can have more unwind strategies to choose from.
Up until now, we've had a bug, which went largely unnoticed, where
unwind info in the manually added symbols files (target symbols add) was
being ignored during unwinding. Reinitializing the UnwindTable fixes
that bug too.
Reviewers: clayborg, jasonmolenda, alexshap
Subscribers: jdoerfert, lldb-commits
Differential Revision: https://reviews.llvm.org/D58347
llvm-svn: 356361
My apologies for the large patch. With the exception of ConstString.h
itself it was entirely produced by sed.
ConstString has exactly one const char * data member, so passing a
ConstString by reference is not any more efficient than copying it by
value. In both cases a single pointer is passed. But passing it by
value makes it harder to accidentally return the address of a local
object.
(This fixes rdar://problem/48640859 for the Apple folks)
Differential Revision: https://reviews.llvm.org/D59030
llvm-svn: 355553
Summary:
While debugging an android process remotely from a windows machine, I
noticed that the modules constructed from an object file in memory only had
information about the architecture. Without knowledge of the OS or environment,
expression evaluation sometimes leads to incorrectly generated code or a
debugger crash. While we cannot know for certain what triple a module
constructed from an in-memory object file will have, we can use the
triple from the target to try and fill in the missing details.
Reviewers: clayborg, zturner, JDevlieghere, compnerd, aprantl, labath
Subscribers: jdoerfert, lldb-commits
Differential Revision: https://reviews.llvm.org/D58405
llvm-svn: 354526
The `ap` suffix is a remnant of lldb's former use of auto pointers,
before they got deprecated. Although all their uses were replaced by
unique pointers, some variables still carried the suffix.
In r353795 I removed another auto_ptr remnant, namely redundant calls to
::get for unique_pointers. Jim justly noted that this is a good
opportunity to clean up the variable names as well.
I went over all the changes to ensure my find-and-replace didn't have
any undesired side-effects. I hope I didn't miss any, but if you end up
at this commit doing a git blame on a weirdly named variable, please
know that the change was unintentional.
llvm-svn: 353912
instead of returning the UUID through by-ref argument and a boolean
value indicating success, we can just return it directly. Since the UUID
class already has an invalid state, it can be used to denote the failure
without the additional bool.
llvm-svn: 353714
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
This parameter was only ever used with the Module set, and
since a SymbolFile is tied to a module, the parameter turns
out to be entirely unnecessary. Furthermore, it doesn't make
a lot of sense to ask a caller to ask SymbolFile which is tied
to Module X to find types for Module Y, but that possibility
was open with the previous interface. By removing this
parameter from the API, it makes it harder to use incorrectly
as well as easier for an implementor to understand what it
needs to do.
llvm-svn: 351133
This method took a SymbolContext but only actually cared about the
case where the m_function member was set. Furthermore, it was
intended to be implemented to parse blocks recursively despite not
documenting this in its name. So we change the name to indicate
that it should be recursive, while also limiting the function
parameter to be a Function&. This lets the caller know what is
required to use it, as well as letting new implementers know what
kind of inputs they need to be prepared to handle.
llvm-svn: 351131
Previously all of these functions accepted a SymbolContext&.
While a CompileUnit is one member of a SymbolContext, there
are also many others, and by passing such a monolithic parameter
in this way it makes the requirements and assumptions of the
API unclear for both callers as well as implementors.
All these methods need is a CompileUnit. By limiting the
parameter type in this way, we simplify the code as well as
make it self-documenting for both implementers and users.
Differential Revision: https://reviews.llvm.org/D56564
llvm-svn: 350943
The function SymbolFile::ParseTypes previously accepted a SymbolContext.
This makes it extremely difficult to implement faithfully, because you
have to account for all possible combinations of members being set in
the SymbolContext. On the other hand, no clients of this function
actually care about implementing this function to this strict of a
standard. AFAICT, there is actually only 1 client in the entire
codebase, and it is the function ParseAllDebugSymbols, which is itself
only called for testing purposes when dumping information. At this
call-site, the only field it sets is the CompileUnit, meaning that an
implementer of a SymbolFile need not worry about any examining or
handling any other fields which might be set.
By restricting this API to accept exactly a CompileUnit& and nothing
more, we can simplify the life of new SymbolFile plugin implementers by
making it clear exactly what the necessary and sufficient set of
functionality they need to implement is, while at the same time removing
some dead code that tried to handle other types of SymbolContext fields
that were never going to be set anyway.
Differential Revision: https://reviews.llvm.org/D56462
llvm-svn: 350889
Summary:
instead of returning the architecture through by-ref argument and a
boolean value indicating success, we can just return the ArchSpec
directly. Since the ArchSpec already has an invalid state, it can be
used to denote the failure without the additional bool.
Reviewers: clayborg, zturner, espindola
Subscribers: emaste, arichardson, JDevlieghere, lldb-commits
Differential Revision: https://reviews.llvm.org/D56129
llvm-svn: 350291
Using compare is verbose, bug prone and potentially inefficient (because
of early termination). Replace relevant call sites with the (in)equality
operator.
llvm-svn: 349972
This patch removes the comments following the header includes. They were
added after running IWYU over the LLDB codebase. However they add little
value, are often outdates and burdensome to maintain.
Differential revision: https://reviews.llvm.org/D54385
llvm-svn: 346625
Replace calls to LLVM's is_directory with calls to LLDB's FileSytem
class. For this I introduced a new convenience method that, like the
other methods, takes either a path or filespec. This still uses the LLVM
functions under the hood.
Differential revision: https://reviews.llvm.org/D54135
llvm-svn: 346375
This patch removes the logic for resolving paths out of FileSpec and
updates call sites to rely on the FileSystem class instead.
Differential revision: https://reviews.llvm.org/D53915
llvm-svn: 345890
This patch removes the Exists method from FileSpec and updates its uses
with calls to the FileSystem.
Differential revision: https://reviews.llvm.org/D53845
llvm-svn: 345854
This patch removes the GetByteSize method from FileSpec and updates its
uses with calls to the FileSystem.
Differential revision: https://reviews.llvm.org/D53788
llvm-svn: 345812
This patch extends the FileSystem class with a bunch of functions that
are currently implemented as methods of the FileSpec class. These
methods will be removed in future commits and replaced by calls to the
file system.
The new functions are operated in terms of the virtual file system which
was recently moved from clang into LLVM so it could be reused in lldb.
Because the VFS is stateful, we turned the FileSystem class into a
singleton.
Differential revision: https://reviews.llvm.org/D53532
llvm-svn: 345783
This is similar to D53597, but following up with 2 more enums.
After this, all flag enums should be strongly typed all the way
through to the symbol files plugins.
Differential Revision: https://reviews.llvm.org/D53616
llvm-svn: 345314
When we get the `resolve_scope` parameter from the SB API, it's a
`uint32_t`. We then pass it through all of LLDB this way, as a uint32.
This is unfortunate, because it means the user of an API never actually
knows what they're dealing with. We can call it something like
`resolve_scope` and have comments saying "this is a value from the
`SymbolContextItem` enumeration, but it makes more sense to just have it
actually *be* the correct type in the actual C++ type system to begin
with. This way the person reading the code just knows what it is.
The reason to use integers instead of enumerations for flags is because
when you do bitwise operations on enumerations they get promoted to
integers, so it makes it tedious to constantly be casting them back
to the enumeration types, so I've introduced a macro to make this
happen magically. By writing LLDB_MARK_AS_BITMASK_ENUM after defining
an enumeration, it will define overloaded operators so that the
returned type will be the original enum. This should address all
the mechanical issues surrounding using rich enum types directly.
This way, we get a better debugger experience, and new users to
the codebase can get more easily acquainted with the codebase because
their IDE features can help them understand what the types mean.
Differential Revision: https://reviews.llvm.org/D53597
llvm-svn: 345313
Summary:
Instead of iterating over our vector of functions, we might as well use a map here to
directly get the function we need.
Thanks to Vedant for pointing this out.
Reviewers: vsk
Reviewed By: vsk
Subscribers: mgrang, lldb-commits
Differential Revision: https://reviews.llvm.org/D50225
llvm-svn: 339504
This change improves the logging for the lldb.module category to note a few interesting cases:
1. Local object file found, but specs not matching
2. Local object file not found, using a placeholder module
The handling and logging for the cases wehre we fail to load compressed dwarf
symbols is also improved.
Differential Revision: https://reviews.llvm.org/D50274
llvm-svn: 339161
Summary:
This has multiple advantages:
- we need only one function argument/instance variable instead of three
- no need to default initialize variables
- no custom parsing code
- VersionTuple has comparison operators, which makes version comparisons much
simpler
Reviewers: zturner, friss, clayborg, jingham
Subscribers: emaste, lldb-commits
Differential Revision: https://reviews.llvm.org/D47889
llvm-svn: 334950
In r331719, I changed Module::FindTypes not to limit the amount
of types returned by the Symbol provider, because we want all
possible matches to be able to filter them. In one code path,
the filtering was applied to the TypeList without changing the
number of types that gets returned. This is turn could cause
consumers to access beyond the end of the TypeList.
This patch fixes this case and also adds an assertion to
TypeList::GetTypeAtIndex to catch those obvious programming
mistakes.
Triggering the condition in which we performed the incorrect
access was not easy. It happened a lot in mixed Swift/ObjectiveC
code, but I was able to trigger it in pure Objective C++ although
in a contrieved way.
rdar://problem/40254997
llvm-svn: 333786
Summary:
As discussed in https://bugs.llvm.org/show_bug.cgi?id=37317,
FindGlobalVariables does not properly handle the case where
append=false. As this doesn't seem to be used in the tree, this patch
removes the parameter entirely.
Reviewers: clayborg, jingham, labath
Reviewed By: clayborg
Subscribers: aprantl, lldb-commits, kubamracek, JDevlieghere
Differential Revision: https://reviews.llvm.org/D46885
Patch by Tom Tromey <ttromey@mozilla.com>.
llvm-svn: 333639
The only reason this was here was so that Module could have a
function called CreateJITModule which created things in a special
order. Instead of making this specific to creating JIT modules,
I converted this into a template function that can create a module
for any type of object file plugin and just forwards arguments
through. Since the template is not instantiated in Core, the linker
(and header file) dependency moves to the point where it is
instantiated, which only happens in Expression. Conceptually, this
location also makes more sense for a dependency on ObjectFileJIT.
After all, we JIT expressions so it's no surprise that Expression
needs to make use of ObjectFileJIT.
Differential Revision: https://reviews.llvm.org/D47228
llvm-svn: 333143
Summary:
... and fix one bug found this way. Currently, the test works not because
types are looked up correctly, but because by injecting local variables
we also materialize the types for Clang. If we disable the local variable
injection, then one check fails.
The reason of the failure is that FindTypes is run with max_matches==1
and this value is passed down to the symbol lookup functions. When the
search is performed only on the basename (like it's the case for an
entity defined in the root namespace), then the search will stop after
having found one match on the basename. But that match might be in a
namespace, we were really just looking up the basename in the accelerator
tables.
The solution is to not pass max_matches down, but to search without a
limit and let RemoveMismatchedTypes do its job afterwards. Note the
patch includes 2 hunks with the same change, but only the latter is
tested. I couldn't find a way to create a testcase for the other
branch of the if ('image lookup -t' allows me to get there, but it
only ever returns one type anyway).
Reviewers: clayborg, jingham
Subscribers: lldb-commits
Differential Revision: https://reviews.llvm.org/D46548
llvm-svn: 331719
This change adds support for two types of Minidump CodeView records:
PDB70 (reference: https://crashpad.chromium.org/doxygen/structcrashpad_1_1CodeViewRecordPDB70.html)
This is by far the most common record type.
ELF BuildID (found in Breakpad/Crashpad generated minidumps)
This would set a proper UUID for placeholder modules, in turn enabling
an accurate match with local module images.
Differential Revision: https://reviews.llvm.org/D46292
llvm-svn: 331394
This patch fixes an issue where we weren't looking for exact matches in the expression parser and also fixed the type lookup logic in the Module.cpp. Tests added to make sure we don't regress.
Differential Revision: https://reviews.llvm.org/D46128
llvm-svn: 331227
This is intended as a clean up after the big clang-format commit
(r280751), which unfortunately resulted in many of the comment
paragraphs in LLDB being very hard to read.
FYI, the script I used was:
import textwrap
import commands
import os
import sys
import re
tmp = "%s.tmp"%sys.argv[1]
out = open(tmp, "w+")
with open(sys.argv[1], "r") as f:
header = ""
text = ""
comment = re.compile(r'^( *//) ([^ ].*)$')
special = re.compile(r'^((([A-Z]+[: ])|([0-9]+ )).*)|(.*;)$')
for line in f:
match = comment.match(line)
if match and not special.match(match.group(2)):
# skip intentionally short comments.
if not text and len(match.group(2)) < 40:
out.write(line)
continue
if text:
text += " " + match.group(2)
else:
header = match.group(1)
text = match.group(2)
continue
if text:
filled = textwrap.wrap(text, width=(78-len(header)),
break_long_words=False)
for l in filled:
out.write(header+" "+l+'\n')
text = ""
out.write(line)
os.rename(tmp, sys.argv[1])
Differential Revision: https://reviews.llvm.org/D46144
llvm-svn: 331197
Normally, LLDB is creating a high-fidelity representation of a live
process, including a list of modules and sections, with the
associated memory address ranges. In order to build the module and
section map LLDB tries to locate the local module image (object file)
and will parse it.
This does not work for postmortem debugging scenarios where the crash
dump (minidump in this case) was captured on a different machine.
Fortunately the minidump format encodes enough information about
each module's memory range to allow us to create placeholder modules.
This enables most LLDB functionality involving address-to-module
translations.
Also, we may want to completly disable the search for matching
local object files if we load minidumps unless we can prove that the
local image matches the one from the crash origin.
(not part of this change, see: llvm.org/pr35193)
Example: Identify the module from a stack frame PC:
Before:
thread #1, stop reason = Exception 0xc0000005 encountered at address 0x164d14
frame #0: 0x00164d14
frame #1: 0x00167c79
frame #2: 0x00167e6d
frame #3: 0x7510336a
frame #4: 0x77759882
frame #5: 0x77759855
After:
thread #1, stop reason = Exception 0xc0000005 encountered at address 0x164d14
frame #0: 0x00164d14 C:\Users\amccarth\Documents\Visual Studio 2013\Projects\fizzbuzz\Debug\fizzbuzz.exe
frame #1: 0x00167c79 C:\Users\amccarth\Documents\Visual Studio 2013\Projects\fizzbuzz\Debug\fizzbuzz.exe
frame #2: 0x00167e6d C:\Users\amccarth\Documents\Visual Studio 2013\Projects\fizzbuzz\Debug\fizzbuzz.exe
frame #3: 0x7510336a C:\Windows\SysWOW64\kernel32.dll
frame #4: 0x77759882 C:\Windows\SysWOW64\ntdll.dll
frame #5: 0x77759855 C:\Windows\SysWOW64\ntdll.dll
Example: target modules list
Before:
error: the target has no associated executable images
After:
[ 0] C:\Windows\System32\MSVCP120D.dll
[ 1] C:\Windows\SysWOW64\kernel32.dll
[ 2] C:\Users\amccarth\Documents\Visual Studio 2013\Projects\fizzbuzz\Debug\fizzbuzz.exe
[ 3] C:\Windows\System32\MSVCR120D.dll
[ 4] C:\Windows\SysWOW64\KERNELBASE.dll
[ 5] C:\Windows\SysWOW64\ntdll.dll
NOTE: the minidump format also includes the debug info GUID, so we can
fill-in the module UUID from it, but this part was excluded from this change
to keep the changes simple (the LLDB UUID is hardcoded to be either 16 or
20 bytes, while the CodeView GUIDs are normally 24 bytes)
Differential Revision: https://reviews.llvm.org/D45700
llvm-svn: 330302