The code in LLDB assumes that CompilerType and friends use the size 0
as a sentinel value to signal an error. This works for C++, where no
zero-sized type exists, but in many other programming languages
(including I believe C) types of size zero are possible and even
common. This is a particular pain point in swift-lldb, where extra
code exists to double-check that a type is *really* of size zero and
not an error at various locations.
To remedy this situation, this patch starts by converting
CompilerType::getBitSize() and getByteSize() to return an optional
result. To avoid wasting space, I hand-rolled my own optional data
type assuming that no type is larger than what fits into 63
bits. Follow-up patches would make similar changes to the ValueObject
hierarchy.
rdar://problem/47178964
Differential Revision: https://reviews.llvm.org/D56688
llvm-svn: 351214
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
Every callsite was passing an empty SymbolContext, so this parameter
had no effect. Inside the DWARF implementation of this function,
however, there was one codepath that checked members of the
SymbolContext. Since no call-sites actually ever used this
functionality, it was essentially dead code, so I've deleted this
code path as well.
llvm-svn: 351132
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
Summary:
This commit adds the glue code necessary to integrate the
SymbolFileBreakpad into the plugin system. Most of the methods are
stubbed out. The only method implemented method is AddSymbols, which
parses the PUBLIC "section" of the breakpad "object file", and fills out
the Module's symtab.
To enable testing this, I've made two additional changes:
- dump Symtab from the SymbolVendor class. The symtab was already being
dumped as a part of the object file dump, but that happened before
symbol vendor kicked in, so it did not reflect any symbols added
there.
- add ability to explicitly specify the external symbol file in
lldb-test (so that the object file could be linked with the breakpad
symbol file). To make things simpler, I've changed lldb-test from
consuming multiple inputs (and dumping their symbols) to having it
just process a single file per invocation. This was not a problem
since everyone was using it that way already.
Reviewers: clayborg, zturner, lemo, markmentovai, amccarth
Subscribers: mgorny, lldb-commits
Differential Revision: https://reviews.llvm.org/D56173
llvm-svn: 350924
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
Typedefs are represented as S_UDT records in the globals stream. This
creates a strange situation where "types" are actually represented as
"symbols", so they need special handling.
In order to test this, we don't just use lldb and print out some
variables causing the AST to get created, because variables whose type
is a typedef will have debug info referencing the original type, not the
typedef. So we use lldb-test instead which will parse all debug info in
the entire file. This exposed some problems with lldb-test and the
native reader, mainly that certain types of obscure symbols which we can
find when iterating every single record would trigger crashes. These
have been fixed as well so that lldb-test can be used to test this
functionality.
Differential Revision: https://reviews.llvm.org/D56461
llvm-svn: 350888
ParseDeclsForContext was originally created to serve the very specific
case where the context is a function block. It was never intended to be
used for arbitrary DeclContexts, however due to the generic name, the
DWARF and PDB plugins implemented it in this way "just in case". Then,
lldb-test came along and decided to use it in that way.
Related to this, there are a set of functions in the SymbolFile class
interface whose requirements and expectations are not documented. For
example, if you call ParseCompileUnitFunctions, there's an inherent
requirement that you create entries in the underlying clang AST for
these functions as well as their signature types, because in order to
create an lldb_private::Function object, you have to pass it a
CompilerType for the parameter representing the signature.
On the other hand, there is no similar requirement (either inherent or
documented) if one were to call ParseDeclsForContext. Specifically, if
one calls ParseDeclsForContext, and some variable declarations, types,
and other things are added to the clang AST, is it necessary to create
lldb::Variable, lldb::Type, etc objects representing them? Nobody knows.
There is, however, an accidental requirement, because since all of the
plugins implemented this just in case, lldb-test came along and used
ParsedDeclsForContext, and then wrote check lines that depended on this.
When I went to try and implemented the NativePDB reader, I did not
adhere to this (in fact, from a layering perspective I went out of my
way to avoid it), and as a result the existing DIA PDB tests don't work
when the native PDB reader is enabled, because they expect that calling
ParseDeclsForContext will modify the *module's* view of symbols, and not
just the internal AST.
All of this confusion, however, can be avoided if we simply stick to
using ParseDeclsForContext for its original intended use case (blocks),
and use a different function (ParseAllDebugSymbols) for its intended use
case which is, unsuprisingly, to parse all the debug symbols (which is
all lldb-test really wanted to do anyway).
In the future, I would like to change ParseDeclsForContext to
ParseDeclsForFunctionBlock, then delete all of the dead code inside that
handles other types of DeclContexts (and probably even assert if the
DeclContext is anything other than a block).
A few PDB tests needed to be fixed up as a result of this, and this also
exposed a couple of bugs in the DIA PDB reader (doesn't matter much
since it should be going away soon, but worth mentioning) where the
appropriate AST entries weren't being created always.
Differential Revision: https://reviews.llvm.org/D56418
llvm-svn: 350764
Summary:
The main difference between the classes was supposed to be the fact that
one is backed by llvm::SmallVector, and the other by std::vector.
However, over the years, they have accumulated various other differences
too.
This essentially removes the std::vector version, as that is pretty much
identical to llvm::SmallVector<T, 0>, and combines their interfaces. It
does not attempt to do a more significant refactoring, even though there
is still a lot of duplication in this file, as it is hard to tell which
quirk of some API is depended on by somebody (and, a previous, more
ambitious attempt at this in D16769 has failed).
I also add some tests, including one which demonstrates one of the
quirks/bugs of the API I have noticed in the process.
Reviewers: clayborg, teemperor, tberghammer
Subscribers: mgorny, JDevlieghere, lldb-commits
Differential Revision: https://reviews.llvm.org/D56170
llvm-svn: 350380
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
This is a first step towards getting lldb-test symbols working
with the native plugin. There is a remaining issue, which is
that the plugin expects that ParseDeclsForContext will also
create lldb symbols rather than just the decls, but the native
pdb plugin doesn't currently do this. This will be addressed
in a followup patch.
llvm-svn: 350243
There were several problems preventing this from working. The
first is that when the PDB had an absolute path to the main
source file, we would construct an invalid path by prepending the
compilation directory to it anyway. So we needed to check if the
path is already absolute first.
Second, LLDB assumes that the zero'th item in the support file list
is the main compilation unit. We were respecting this requirement,
but LLDB *also* requires that file to appear somewhere in the list
starting from index 1 as well. So the main compilation file should
appear in the support file list twice. And when parsing a line
table, it expects the LineEntry records to be constructed using
the 1-based index. With these two fixes we can now set breakpoints
by file and line using the native PDB reader.
llvm-svn: 350240
Summary:
r346165 introduced a bug, where we would fail to parse the size of an
array if that size happened to match an existing die offset.
The logic was:
if (DWARFDIE count = die.GetReferencedDie(DW_AT_count))
num_elements = compute_vla_size(count);
else
num_elements = die.GetUsigned(DW_AT_count); // a fixed-size array
The problem with this logic was that GetReferencedDie did not take the
form class of the attribute into account, and would happily return a die
reference for any form, if its value happened to match some die.
As this behavior is inconsistent with how llvm's DWARFFormValue class
operates, I chose to fix the problem by making our version of this class
match the llvm behavior. For this to work, I had to add an explicit form
class check to the .apple_XXX tables parsing code, because they do
(incorrectly?) use data forms as die references.
Reviewers: aprantl, clayborg
Subscribers: JDevlieghere, lldb-commits
Differential Revision: https://reviews.llvm.org/D55991
llvm-svn: 350086
Previously we would create these for local variables but not for
global variables.
Also updated existing tests which created global variables to check
for them in the resulting AST.
llvm-svn: 349854
We had a use after free where we were assigning the result of a function
that returned a string to a StringRef. After fixing this use after
free, one of the DIA PDB tests now passes with the native PDB reader,
so we enable the test under native mode as well. The goal is to
eventually make all the tests pass under both, at which point we can
disable them all under DIA mode.
llvm-svn: 349673
We reconstruct the AST hierarchy by trying to hack up a mangled
name for the parent type using the child type's mangled name.
This was failing for enums because their tag type is represented
with two letters ("W4") instead of one letter ("T", "U", etc) as
it is with classes, structs, and unions. After accounting for
this we can now correctly determine when an enum is nested
inside of a namespace or a class.
llvm-svn: 349565
Previously the code that parsed debug info to create lldb's Symbol
objects such as Variable, Type, Function, etc was tightly coupled
to the AST reconstruction code. This made it difficult / impossible
to implement functions such as ParseDeclsForContext() that were only
supposed to be operating on clang AST's. By splitting these apart,
the logic becomes much cleaner and we have a clear separation of
responsibilities.
llvm-svn: 349383
This patch simplifies boolean expressions acorss LLDB. It was generated
using clang-tidy with the following command:
run-clang-tidy.py -checks='-*,readability-simplify-boolean-expr' -format -fix $PWD
Differential revision: https://reviews.llvm.org/D55584
llvm-svn: 349215
This patch adds support for parsing and evaluating local variables.
using the native pdb plugin.
Differential Revision: https://reviews.llvm.org/D55575
llvm-svn: 349067
Previously CreateParameterDeclaration was always using the translation
unit DeclContext. We would later go and add parameters to the
FunctionDecl, but internally clang makes a copy when you do this, and
we'd end up with ParmVarDecl's at the global scope as well as in the
function scope.
This fixes the issue. It's hard to say whether this will introduce
a behavioral change in name lookup, but I know there have been several
hacks introduced in previous years to deal with collisions between
various types of variables, so there's a chance that this patch could
obviate one of those hacks.
Differential Revision: https://reviews.llvm.org/D55571
llvm-svn: 348941
Previously we would create an lldb::Function object for each function
parsed, but we would not add these to the clang AST. This is a first
step towards getting local variable support working, as we first need an
AST decl so that when we create local variable entries, they have the
proper DeclContext.
Differential Revision: https://reviews.llvm.org/D55384
llvm-svn: 348631
VarStreamArray was built on the assumption that it is backed by a
StreamRef, and offset 0 of that StreamRef is the first byte of the first
record in the array.
This is a logical and intuitive assumption, but unfortunately we have
use cases where it doesn't hold. Specifically, a PDB module's symbol
stream is prefixed by 4 bytes containing a magic value, and the first
byte of record data in the array is actually at offset 4 of this byte
sequence.
Previously, we would just truncate the first 4 bytes and then construct
the VarStreamArray with the resulting StreamRef, so that offset 0 of the
underlying stream did correspond to the first byte of the first record,
but this is problematic, because symbol records reference other symbol
records by the absolute offset including that initial magic 4 bytes. So
if another record wants to refer to the first record in the array, it
would say "the record at offset 4".
This led to extremely confusing hacks and semantics in loading code, and
after spending 30 minutes trying to get some math right and failing, I
decided to fix this in the underlying implementation of VarStreamArray.
Now, we can say that a stream is skewed by a particular amount. This
way, when we access a record by absolute offset, we can use the same
values that the records themselves contain, instead of having to do
fixups.
Differential Revision: https://reviews.llvm.org/D55344
llvm-svn: 348499
Summary:
This patch contains several small fixes, which makes it possible to evaluate
expressions on Windows using information from PDB. The changes are:
- several sanitize checks;
- make IRExecutionUnit::MemoryManager::getSymbolAddress to not return a magic
value on a failure, because callers wait 0 in this case;
- entry point required to be a file address, not RVA, in the ObjectFilePECOFF;
- do not crash on a debuggee second chance exception - it may be an expression
evaluation crash. Also fix detection of "crushed" threads in tests;
- create parameter declarations for functions in AST to make it possible to call
debugee functions from expressions;
- relax name searching rules for variables, functions, namespaces and types. Now
it works just like in the DWARF plugin;
- fix endless recursion in SymbolFilePDB::ParseCompileUnitFunctionForPDBFunc.
Reviewers: zturner, asmith, stella.stamenova
Reviewed By: stella.stamenova, asmith
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D53759
llvm-svn: 348136
This reverts commit dec87759523b2f22fcff3325bc2cd543e4cda0e7.
This commit caused the tests on Windows to run forever rather than complete.
Reverting until the commit can be fixed to not stall.
llvm-svn: 348009
Summary:
This patch contains several small fixes, which makes it possible to evaluate
expressions on Windows using information from PDB. The changes are:
- several sanitize checks;
- make IRExecutionUnit::MemoryManager::getSymbolAddress to not return a magic
value on a failure, because callers wait 0 in this case;
- entry point required to be a file address, not RVA, in the ObjectFilePECOFF;
- do not crash on a debuggee second chance exception - it may be an expression
evaluation crash;
- create parameter declarations for functions in AST to make it possible to call
debugee functions from expressions;
- relax name searching rules for variables, functions, namespaces and types. Now
it works just like in the DWARF plugin;
- fix endless recursion in SymbolFilePDB::ParseCompileUnitFunctionForPDBFunc.
Reviewers: zturner, asmith, stella.stamenova
Reviewed By: stella.stamenova, asmith
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D53759
llvm-svn: 347962
Summary:
This patch adds possibility of searching a public symbol with name and type in
a symbol file, not only in a symtab. It is helpful when working with PE, because
PE's symtabs contain only imported / exported symbols only. Such a search is
required for e.g. evaluation of an expression that calls some function of
the debuggee.
Reviewers: zturner, asmith, labath, clayborg, espindola
Reviewed By: clayborg
Subscribers: davide, emaste, arichardson, aleksandr.urakov, jingham,
lldb-commits, stella.stamenova
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D53368
llvm-svn: 347960
A skeleton compilation unit may contain the DW_AT_str_offsets_base attribute
that points to the first string offset of the CU contribution to the
.debug_str_offsets. At the same time, when we use split dwarf,
the corresponding split debug unit also
may use DW_FORM_strx* forms pointing to its own .debug_str_offsets.dwo.
In that case, DWO does not contain DW_AT_str_offsets_base, but LLDB
still need to know and skip the .debug_str_offsets.dwo section header to
access the offsets.
The patch implements the support of DW_AT_str_offsets_base.
Differential revision: https://reviews.llvm.org/D54844
llvm-svn: 347859
The issue happens because starting from DWARF v5
DW_AT_addr_base attribute should be used
instead of DW_AT_GNU_addr_base. LLDB does not do that and
we end up reading the .debug_addr header as section content
(as addresses) instead of skipping it and reading the real addresses.
Then LLDB is unable to match 2 similar locations and
thinks they are different.
Differential revision: https://reviews.llvm.org/D54751
llvm-svn: 347842
When trying to fix the bots we expected that the cast would be needed in
different places. Ultimately it turned out only the
SymbolFileDWARFDebugMap was affected so, as Pavel correctly notes, it
makes more sense to do the cast just there instead of in teh FS.
llvm-svn: 347660
After a recent change in LLVM the TimePoint encoding become more
precise, exceeding the precision of the TimePoint obtained from the
DebugMap. This patch adds a flag to the GetModificationTime helper in
the FileSystem to return the modification time with less precision.
Thanks to Davide for bisecting this failure on the LLDB bots.
llvm-svn: 347615
