GCC ToT doesn't do this & it's worth about 3.2% on Clang's DWO file size
with Clang. Some or all of this may be due to things like r190715 which
could have source fixes/improvements, but it's not clear that's the case
and that doesn't help other source bases.
llvm-svn: 190716
By removing the possibility of strange partial definitions with no
members that older GCC's produced for the otherwise unreferenced outer
types of referenced inner types, we can simplify debug info generation
and correct this bug. Newer (4.8.1 and ToT) GCC's don't produce this
quirky debug info, and instead produce the full definition for the outer
type (except in the case where that type is dynamic and its vtable is
not emitted in this TU).
During the creation of the context for a type, we may revisit that type
(due to the need to visit template parameters, among other things) and
used to end up visiting it first there. Then when we would reach the
original code attempting to define that type, we would lose debug info
by overwriting its members.
By avoiding the possibility of latent "defined with no members" types,
we can be sure than whenever we already have a type in a cache (either a
definition or declaration), we can just return that. In the case of a
full definition, our work is done. In the case of a partial definition,
we must already be in the process of completing it. And in the case of a
declaration, the completed/vtable/etc callbacks can handle converting it
to a definition.
llvm-svn: 190122
Debug info emission was tripping over an IRGen bug (fixed in r189996)
that was resulting in duplicate emission of static data members of class
templates in namespaces.
We could add more test coverage to debug info for this issue
specifically, but I think the underlying IRGen test is more targeted and
sufficient for the issue.
llvm-svn: 190001
We use CXX mangler to generate unique identifier for external C++ struct,
union, class and enum. Types with unique identifier are added to retained
types by DIBuilder.
Testing cases are updated to reflect the unique identifier generated for types.
The order of MDNodes is changed because of retained types and testing cases
are updated accordingly.
Testing case debug-info-uuid.cpp now emits error with Itanium mangler, since
uuid is not yet handled in Itanium mangler. And it will check for the error
message.
llvm-svn: 189622
We had further discussions on how to retain types, whether to do it in front end
or in DIBuilder. And we agree to do it in DIBuilder so front ends
generating unique identifier do not need to worry about retaining them.
llvm-svn: 189609
We use CXX mangler to generate unique identifier for external C++ struct,
union, class and enum. Types with unique identifier are added to RetainedTypes
to make sure they are treated as used even when all uses are replaced with
the identifiers.
A single type can be added to RetainedTypes multiple times. For example, both
createForwardDecl and createLimitedType can add the same type to RetainedTypes.
A set is used to avoid duplication when updating AllRetainTypes in DIBuilder.
Testing cases are updated to reflect the unique identifier generated for types.
The order of MDNodes is changed because of retained types and testing cases
are updated accordingly.
Testing case debug-info-uuid.cpp now emits error with Itanium mangler, since
uuid is not yet handled in Itanium mangler.
We choose to update RetainedTypes in clang, then at finalize(), we update
AllRetainTypes in DIBuilder. The other choice is to update AllRetainTypes
in DIBuilder when creating a DICompositeType with unique identifier. This
option requires using ValueHandle for AllRetainTypes in DIBuilder since
the created DICompositeType can be modified later on by setContainingType etc.
llvm-svn: 189600
Both functions will take a Type pointer instead of a Decl pointer. This helps
with follow-up type uniquing patches, which need the Type pointer to call
CXX mangler to generate unique identifiers.
No functionality change.
llvm-svn: 189519
In the transition from declaration (with some members) to definition, we
were overwriting the list of members with the empty list when attaching
template parameters.
The fix is in llvm::DICompositeType::addMember (along with asserts that
cause this bug to be covered by existing Clang test cases), including
adding some asserts to catch this sort of issue which found issues fixed
in this commit.
llvm-svn: 189494
This reverts commit r189320.
Alexey Samsonov and Dmitry Vyukov presented some arguments for keeping
these around - though it still seems like those tasks could be solved by
a tool just using the symbol table. In a very small number of cases,
thunks may be inlined & debug info might be able to save profilers &
similar tools from misclassifying those cases as part of the caller.
The extra changes here plumb through the VarDecl for various cases to
CodeGenFunction - this provides better fidelity through a few APIs but
generally just causes the CGF::StartFunction to fallback to using the
name of the IR function as the name in the debug info.
The changes to debug-info-global-ctor-dtor.cpp seem like goodness. The
two names that go missing (in favor of only emitting those names as
linkage names) are names that can be demangled - emitting them only as
the linkage name should encourage tools to do just that.
Again, thanks to Dinesh Dwivedi for investigation/work on this issue.
llvm-svn: 189421
Summary:
Previously the backend wouldn't get to see the underlying GlobalValue
that corresponds to the template argument because it would be hidden by
a cast at the IR level. Instead strip the pointer casts off of the
value until we see the underlying GlobalValue.
Reviewers: dblaikie, echristo, majnemer
Reviewed By: majnemer
CC: cfe-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D1508
llvm-svn: 189200
Summary:
This allows us to handle the general case where a non-type template
argument evaluates to a constant expression which isn't integral or a
declaration.
This fixes PR16939.
Reviewers: dblaikie, rsmith
Reviewed By: dblaikie
CC: cfe-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D1453
llvm-svn: 189165
This reverts commit r188687 (reverts r188642 (reverts 188600 (reverts
188576))).
With added test coverage & fix for -gline-tables-only.
Thanks Michael Gottesman for reverting this patch when it demonstrated
problems & providing a reproduction/details to help me track this down.
llvm-svn: 188739
This reverts commit r188642.
This change is causing LTO builds to cause our 16 GB machines to swap and OOM
all weekend. I am going to work with Dave Blaikie to resolve the issue.
Sorry Dave =(.
llvm-svn: 188687
This reverts commit r188600.
r188640/r188639 fixed the root cause of the crash-on-valid that r188600
originally introduced. This now appears to bootstrap debug clang
successfully to the best of my testing.
llvm-svn: 188642
A partner to r188639, this is a somewhat heavy-handed fix to the general
issue, since even after that prior change the issue does still
unavoidably arise with template parameters (see test case).
There are other ways we could consider addressing this (see FIXME).
llvm-svn: 188640
Possible minor reduction in debug info & avoid some cases where creating
a context chain could lead to the type the context chain is being
created for, being created. (this is still possible with template
parameters - tests/fixes/improvements to follow)
llvm-svn: 188639
Fixes a crash-on-valid introduced by r188486 (which should've occurred
earlier but for a blatant bug where calling createFwdDecl from the
requireCompleteType callback was useless under -flimit-debug-info and we
were just getting lucky with other later callbacks requiring the type
anyway).
llvm-svn: 188622
Updated test case to not rely on line numbers in more cases (it's hard
to use the @ check syntax for debug info test cases (due to the
interesting ordering of metadata) and this case in particular (given the
hash-line directive)) - left a few in there to cover the line number
information for these.
llvm-svn: 188585