ExternalASTMerger has hitherto relied on being able to look up
any Decl through its named DeclContext chain. This works for
many cases, but causes problems for function-local structs,
which cannot be looked up in their containing FunctionDecl. An
example case is
void f() {
{ struct S { int a; }; }
{ struct S { bool b; }; }
}
It is not possible to lookup either of the two Ses individually
(or even to provide enough information to disambiguate) after
parsing is over; and there is typically no need to, since they
are invisible to the outside world.
However, ExternalASTMerger needs to be able to complete either
S on demand. This led to an XFAIL on test/Import/local-struct,
which this patch removes. The way the patch works is:
It defines a new data structure, ExternalASTMerger::OriginMap,
which clients are expected to maintain (default-constructing
if the origin does not have an ExternalASTMerger servicing it)
As DeclContexts are imported, if they cannot be looked up by
name they are placed in the OriginMap. This allows
ExternalASTMerger to complete them later if necessary.
As DeclContexts are imported from an origin that already has
its own OriginMap, the origins are forwarded – but only for
those DeclContexts that are actually used. This keeps the
amount of stored data minimal.
The patch also applies several improvements from review:
- Thoroughly documents the interface to ExternalASTMerger;
- Adds optional logging to help track what's going on; and
- Cleans up a bunch of braces and dangling elses.
Differential Revision: https://reviews.llvm.org/D38208
llvm-svn: 314336
viewing of the final IR. This is useful for confirming that
structure layout was correct.
I've added two tests:
- A test that checks that structs in top-level code are completed
correctly during struct layout (they are)
- A test that checks that structs defined in function bodies are
cpmpleted correctly during struct layout (currently they are not,
so this is XFAIL).
The second test fails because LookupSameContext()
(ExternalASTMerger.cpp) can't find the struct. This is an issue I
intend to resolve separately.
Differential Revision: https://reviews.llvm.org/D36429
llvm-svn: 310318
This patch adds functionality and a test for importing Objective-C classes
and their methods.
It also adds a flag to clang-import-test to set the language used for
parsing. This takes the same argument format as the -x option to the
driver.
Differential Revision: https://reviews.llvm.org/D35274
llvm-svn: 309014
- eliminated error handling for the indirect CompilerInstance, which should
never generate an error as it is created;
- added a new test for direct importation; and
- removed an unused implementation of the CompleteType() API.
This brings clang-import-test.cpp and ExternalASTMerge.cpp back to 100%
coverage on all metrics measured by DLLVM_BUILD_INSTRUMENTED_COVERAGE.
Differential Revision: https://reviews.llvm.org/D35220
llvm-svn: 307600
Summary:
setMustBuildLookupTable should be called on imported TagDecls otherwise we may fail
to import their member decls (if they have any).
Not calling the setMustBuildLookupTable method results in a failure in the attached test
case when lookup for the 'x' member fails on struct S, which hasn't had its decls imported
elsewhere. (By contrast the member-in-struct testcase hasn't run into this issue
because the import of its decls is triggered when the struct instance is defined, and the
member access follows this).
Reviewers: spyffe, rsmith
Reviewed By: spyffe, rsmith
Differential Revision: https://reviews.llvm.org/D34253
llvm-svn: 305619
ASTImporter has some bugs when it's importing types
that themselves come from an ExternalASTSource. This
is exposed particularly in the behavior when
comparing complete TagDecls with forward
declarations. This patch does several things:
- Adds a test case making sure that conflicting
forward-declarations are resolved correctly;
- Extends the clang-import-test harness to test
two-level importing, so that we make sure we
complete types when necessary; and
- Fixes a few bugs I found this way. Failure to
complete types was one; however, I also discovered
that complete RecordDecls aren't properly added to
the redecls chain for existing forward
declarations.
llvm-svn: 302975
clang-import-test has until now been only able to report top-level Decls.
This is clearly insufficient; we should be able to look inside structs
and namespaces also. This patch adds new test cases for a variety of
lookups inside existing ASTContexts, and adds the functionality necessar
to make most of these testcases work. (One testcase is known to fail
because of ASTImporter limitations when importing templates; I'll look
into that separately.)
This patch also separates the core functionality out into
ExternalASTMerger, an interface that allows clients like LLDB to make
use of it. clang-import-test now only has the machinery necessary to
set up the tests.
Differential revision: https://reviews.llvm.org/D30435
llvm-svn: 299976
Recommitted after formal approval.
LLVM's JIT is now the foundation of dynamic-compilation features for many languages. Clang also has low-level support for dynamic compilation (ASTImporter and ExternalASTSource, notably). How the compiler is set up for dynamic parsing is generally left up to individual clients, for example LLDB's C/C++/Objective-C expression parser and the ROOT project.
Although this arrangement offers external clients the flexibility to implement dynamic features as they see fit, the lack of an in-tree client means that subtle bugs can be introduced that cause regressions in the external clients but aren't caught by tests (or users) until much later. LLDB for example regularly encounters complicated ODR violation scenarios where it is not immediately clear who is at fault.
Other external clients (notably, Cling) rely on similar functionality, and another goal is to break this functionality up into composable parts so that any client can be built easily on top of Clang without requiring extensive additional code.
I propose that the parts required to build a simple expression parser be added to Clang. Initially, I aim to have the following features:
A piece that looks up external declarations from a variety of sources (e.g., from previous dynamic compilations, from modules, or from DWARF) and uses clear conflict resolution rules to reconcile differences, with easily understood errors. This functionality will be supported by in-tree tests.
A piece that works hand in hand with the LLVM JIT to resolve the locations of external declarations so that e.g. variables can be redeclared and (for high-performance applications like DTrace) external variables can be accessed directly from the registers where they reside.
This commit adds a tester that parses a sequence of source files and then uses them as source data for an expression. External references are resolved using an ExternalASTSource that responds to name queries using an ASTImporter. This is the setup that LLDB uses, and the motivating reason for MinimalImport in ASTImporter. When complete, this tester will implement the first of the above goals.
Differential Revision: https://reviews.llvm.org/D27180
llvm-svn: 290367
LLVM's JIT is now the foundation of dynamic-compilation features for many languages. Clang also has low-level support for dynamic compilation (ASTImporter and ExternalASTSource, notably). How the compiler is set up for dynamic parsing is generally left up to individual clients, for example LLDB's C/C++/Objective-C expression parser and the ROOT project.
Although this arrangement offers external clients the flexibility to implement dynamic features as they see fit, the lack of an in-tree client means that subtle bugs can be introduced that cause regressions in the external clients but aren't caught by tests (or users) until much later. LLDB for example regularly encounters complicated ODR violation scenarios where it is not immediately clear who is at fault.
Other external clients (notably, Cling) rely on similar functionality, and another goal is to break this functionality up into composable parts so that any client can be built easily on top of Clang without requiring extensive additional code.
I propose that the parts required to build a simple expression parser be added to Clang. Initially, I aim to have the following features:
- A piece that looks up external declarations from a variety of sources (e.g., from previous dynamic compilations, from modules, or from DWARF) and uses clear conflict resolution rules to reconcile differences, with easily understood errors. This functionality will be supported by in-tree tests.
- A piece that works hand in hand with the LLVM JIT to resolve the locations of external declarations so that e.g. variables can be redeclared and (for high-performance applications like DTrace) external variables can be accessed directly from the registers where they reside.
This commit adds a tester that parses a sequence of source files and then uses them as source data for an expression. External references are resolved using an ExternalASTSource that responds to name queries using an ASTImporter. This is the setup that LLDB uses, and the motivating reason for MinimalImport in ASTImporter. When complete, this tester will implement the first of the above goals.
Differential Revision: https://reviews.llvm.org/D27180
llvm-svn: 290004