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
Recently I tried to port LLDB's lit configuration files over to use a
on the surface, but broke some cases that weren't broken before and also
exposed some additional problems with the old approach that we were just
getting lucky with.
When we set up a lit environment, the goal is to make it as hermetic as
possible. We should not be relying on PATH and enabling the use of
arbitrary shell commands. Instead, only whitelisted commands should be
allowed. These are, generally speaking, the lit builtins such as echo,
cd, etc, as well as anything for which substitutions have been
explicitly set up for. These substitutions should map to the build
output directory, but in some cases it's useful to be able to override
this (for example to point to an installed tools directory).
This is, of course, how it's supposed to work. What was actually
happening is that we were bringing in PATH and LD_LIBRARY_PATH and then
just running the given run line as a shell command. This led to problems
such as finding the wrong version of clang-cl on PATH since it wasn't
even a substitution, and flakiness / non-determinism since the
environment the tests were running in would change per-machine. On the
other hand, it also made other things possible. For example, we had some
tests that were explicitly running cl.exe and link.exe instead of
clang-cl and lld-link and the only reason it worked at all is because it
was finding them on PATH. Unfortunately we can't entirely get rid of
these tests, because they support a few things in debug info that
clang-cl and lld-link don't (notably, the LF_UDT_MOD_SRC_LINE record
which makes some of the tests fail.
The high level changes introduced in this patch are:
1. Removal of functionality - The lit test suite no longer respects
LLDB_TEST_C_COMPILER and LLDB_TEST_CXX_COMPILER. This means there is no
more support for gcc, but nobody was using this anyway (note: The
functionality is still there for the dotest suite, just not the lit test
suite). There is no longer a single substitution %cxx and %cc which maps
to <arbitrary-compiler>, you now explicitly specify the compiler with a
substitution like %clang or %clangxx or %clang_cl. We can revisit this
in the future when someone needs gcc.
2. Introduction of the LLDB_LIT_TOOLS_DIR directory. This does in spirit
what LLDB_TEST_C_COMPILER and LLDB_TEST_CXX_COMPILER used to do, but now
more friendly. If this is not specified, all tools are expected to be
the just-built tools. If it is specified, the tools which are not
themselves being tested but are being used to construct and run checks
(e.g. clang, FileCheck, llvm-mc, etc) will be searched for in this
directory first, then the build output directory.
3. Changes to core llvm lit files. The use_lld() and use_clang()
functions were introduced long ago in anticipation of using them in
lldb, but since they were never actually used anywhere but their
respective problems, there were some issues to be resolved regarding
generality and ability to use them outside their project.
4. Changes to .test files - These are all just replacing things like
clang-cl with %clang_cl and %cxx with %clangxx, etc.
5. Changes to lit.cfg.py - Previously we would load up some system
environment variables and then add some new things to them. Then do a
bunch of work building out our own substitutions. First, we delete the
system environment variable code, making the environment hermetic. Then,
we refactor the substitution logic into two separate helper functions,
one which sets up substitutions for the tools we want to test (which
must come from the build output directory), and another which sets up
substitutions for support tools (like compilers, etc).
6. New substitutions for MSVC -- Previously we relied on location of
MSVC by bringing in the entire parent's PATH and letting
subprocess.Popen just run the command line. Now we set up real
substitutions that should have the same effect. We use PATH to find
them, and then look for INCLUDE and LIB to construct a substitution
command line with appropriate /I and /LIBPATH: arguments. The nice thing
about this is that it opens the door to having separate %msvc-cl32 and
%msvc-cl64 substitutions, rather than only requiring the user to run
vcvars first. Because we can deduce the path to 32-bit libraries from
64-bit library directories, and vice versa. Without these substitutions
this would have been impossible.
Differential Revision: https://reviews.llvm.org/D54567
llvm-svn: 347216
A year or so ago, I re-wrote most of the lit infrastructure in LLVM so
that it wasn't so boilerplate-y. I added lots of common helper type
stuff, simplifed usage patterns, and made the code more elegant and
maintainable.
We migrated to this in LLVM, clang, and lld's lit files, but not in
LLDBs. This started to bite me recently, as the 4 most recent times I
tried to run the lit test suite in LLDB on a fresh checkout the first
thing that would happen is that python would just start crashing with
unhelpful backtraces and I would have to spend time investigating.
You can reproduce this today by doing a fresh cmake generation, doing
ninja lldb and then python bin/llvm-lit.py -sv ~/lldb/lit/SymbolFile at
which point you'll get a segfault that tells you nothing about what your
problem is.
I started trying to fix the issues with bandaids, but it became clear
that the proper solution was to just bring in the work I did in the rest
of the projects. The side benefit of this is that the lit configuration
files become much cleaner and more understandable as a result.
Differential Revision: https://reviews.llvm.org/D54009
llvm-svn: 346008
Summary:
- Fix a null array access bug. This happens when creating the lldb type for a function that has no argument.
- Implement SymbolFilePDB::ParseTypes method. Using `lldb-test symbols` will show all supported types in the target.
- Create lldb types for variadic function, PDBSymbolTypePointer, PDBSymbolTypeBuiltin
- The underlying builtin type for PDBSymbolTypeEnum is always `Int`, correct it with the very first enumerator's encoding if any. This is more accurate when the underlying type is not signed or another integer type.
- Fix a bug when the compiler type is not created based on PDB_BuiltinType. For example, basic type `long` is of same width as `int` in a 32-bit target, and the compiler type of former one will be represented by the one generated for latter if using the default method. Introduce a static function GetBuiltinTypeForPDBEncodingAndBitSize to correct this issue.
- Basic type `long double` and `double` have the same bit size in MSVC and there is no information in a PDB to distinguish them. The compiler type of the former one is represented by the latter's.
- There is no line information about typedef, enum etc in a PDB and the source and line information for them are not shown.
- There is no information about scoped enumeration. The compiler type is represented as an unscoped one.
Reviewers: zturner, lldb-commits
Reviewed By: zturner
Subscribers: majnemer, llvm-commits
Differential Revision: https://reviews.llvm.org/D42434
llvm-svn: 323255
Summary:
- Fix a null array access bug. This happens when creating the lldb type for a function that has no argument.
- Implement SymbolFilePDB::ParseTypes method. Using `lldb-test symbols` will show all supported types in the target.
- Create lldb types for variadic function, PDBSymbolTypePointer, PDBSymbolTypeBuiltin
- The underlying builtin type for PDBSymbolTypeEnum is always `Int`, correct it with the very first enumerator's encoding if any. This is more accurate when the underlying type is not signed or another integer type.
- Fix a bug when the compiler type is not created based on PDB_BuiltinType. For example, basic type `long` is of same width as `int` in a 32-bit target, and the compiler type of former one will be represented by the one generated for latter if using the default method. Introduce a static function GetBuiltinTypeForPDBEncodingAndBitSize to correct this issue.
- Basic type `long double` and `double` have the same bit size in MSVC and there is no information in a PDB to distinguish them. The compiler type of the former one is represented by the latter's.
- There is no line informaton about typedef, enum etc in a PDB and the source and line information for them are not shown.
- There is no information about scoped enumeration. The compiler type is represented as an unscoped one.
Reviewers: zturner, lldb-commits, davide, asmith
Reviewed By: zturner, asmith
Subscribers: llvm-commits, davide
Differential Revision: https://reviews.llvm.org/D41427
llvm-svn: 322995