There's a nuanced check about when to use suffixes on these integer
non-type-template-parameters, but when rebuilding names for
-gsimple-template-names there isn't enough data in the DWARF to
determine when to use suffixes or not. So turn on suffixes always to
make it easy to match up names in llvm-dwarfdump --verify.
I /think/ if we correctly modelled auto non-type-template parameters
maybe we could put suffixes only on those. But there's also some logic
in Clang that puts the suffixes on overloaded functions - at least
that's what the parameter says (see D77598 and printTemplateArguments
"TemplOverloaded" parameter) - but I think maybe it's for anything that
/can/ be overloaded, not necessarily only the things that are overloaded
(the argument value is hardcoded at the various callsites, doesn't seem
to depend on overload resolution/searching for overloaded functions). So
maybe with "auto" modeled more accurately, and differentiating between
function templates (always using type suffixes there) and class/variable
templates (only using the suffix for "auto" types) we could correctly
use integer type suffixes only in the minimal set of cases.
But that seems all too much fuss, so let's just put integer type
suffixes everywhere always in the debug info of integer non-type
template parameters in template names.
(more context:
* https://reviews.llvm.org/D77598#inline-1057607
* https://groups.google.com/g/llvm-dev/c/ekLMllbLIZg/m/-dhJ0hO1AAAJ )
Differential Revision: https://reviews.llvm.org/D111477
Using the preferred name creates a mismatch between the textual name of
a type and the DWARF tags describing the parameters as well as possible
inconsistency between DWARF producers (like Clang and GCC, or
older/newer Clang versions, etc).
This improves diagnostic (& important to me, DWARF) accuracy - otherwise
there could be ambiguities between "std::nullptr_t" and some user-defined
type that's /actually/ "nullptr_t" defined in the global namespace.
Differential Revision: https://reviews.llvm.org/D110044
eg: t1<void () const> - DWARF doesn't have a particularly nice way to
encode this, for real member function types (like `void (t1::*)()
const`) the const-ness is encoded in the type of the artificial first
parameter. But `void () const` has no parameters, so encode it like a
normal const-qualified type, using DW_TAG_const_type. (similarly for
restrict and volatile)
Reference qualifiers (& and &&) coming in a separate commit shortly.
It looks like this array was missed in 4276d4a8d0
Fixed tests that expected `elements` to be empty or depeneded on the order of the empty DINode.
Reviewed By: aprantl
Differential Revision: https://reviews.llvm.org/D107024
Empty packs in the non-final position would result in an extra ", ".
Empty packs in the final position would result in missing the space
between trailing >>.
It's noteworthy that GCC has the same bug here, which is a bit
surprising. Both Clang and GCC's bug is only for function template
arguments that are themselves templates with default template arguments
(f1<t1<int[, missing_default_here]>>). Probably because function name
matching isn't generally necessary - whereas type matching is necessary
for DWARF consumers to associate declarations and definitions across
translation units, so the bug's been addressed there already - but
continued to exist for function templates since it's fairly benign
there.
I came across this while working on a change that could reconstitute
these pretty printed names based on the rest of the DWARF, reducing the
size of the DWARF by not having to encode all the template parameters in
the name string. That reconstitution code can't tell the difference
between a defaulted argument or not, so couldn't create the current
buggy-ish output.
Making the names more consistent between direct and indirect references,
and between function and class templates seems all to the good.
(I fixed the function template version of this a few years back in
9fdd09a4cc - clearly I should've looked
more closely and generalized the code better so it only had to be fixed
once - well, doing that here now)
This ensures these types have distinct names if they are distinct types
(eg: if one is an instantiation with a type in one inline namespace, and
another from a type with the same simple name, but in a different inline
namespace).
parameters.
It appears that LLVM isn't able to generate a DW_AT_const_value for a
constant of class type, but if it could, we'd match GCC's debug info in
this case, and in the interim we no longer crash.
template parameters.
No support for the new kinds of non-type template argument yet.
This is not entirely NFC for prior language modes: we have historically
incorrectly accepted rvalue references as the types of non-type template
parameters. Such invalid code is now rejected.
The difference from the previous try is that we no longer directly
access function declarations from position independent executables. It
should work, but currently doesn't with some linkers.
It now includes a fix to not mark available_externally definitions as
dso_local.
Original message:
Start setting dso_local in clang.
This starts adding dso_local to clang.
The hope is to eventually have TargetMachine::shouldAssumeDsoLocal go
away. My objective for now is to move enough of it to clang to remove
the need for the TargetMachine one to handle PIE copy relocations and
-fno-plt. With that it should then be easy to implement a
-fno-copy-reloc in clang.
This patch just adds the cases where we assume a symbol to be local
based on the file being compiled for an executable or a shared
library.
llvm-svn: 324535
This reverts commit r324500.
The bots found two failures:
ThreadSanitizer-x86_64 :: Linux/pie_no_aslr.cc
ThreadSanitizer-x86_64 :: pie_test.cc
when using gold. The issue is a limitation in gold when building pie
binaries. I will investigate how to work around it.
llvm-svn: 324505
It now includes a fix to not mark available_externally definitions as
dso_local.
Original message:
Start setting dso_local in clang.
This starts adding dso_local to clang.
The hope is to eventually have TargetMachine::shouldAssumeDsoLocal go
away. My objective for now is to move enough of it to clang to remove
the need for the TargetMachine one to handle PIE copy relocations and
-fno-plt. With that it should then be easy to implement a
-fno-copy-reloc in clang.
This patch just adds the cases where we assume a symbol to be local
based on the file being compiled for an executable or a shared
library.
llvm-svn: 324500
This starts adding dso_local to clang.
The hope is to eventually have TargetMachine::shouldAssumeDsoLocal go
away. My objective for now is to move enough of it to clang to remove
the need for the TargetMachine one to handle PIE copy relocations and
-fno-plt. With that it should then be easy to implement a
-fno-copy-reloc in clang.
This patch just adds the cases where we assume a symbol to be local
based on the file being compiled for an executable or a shared
library.
llvm-svn: 324107
Preparation to implement DW_AT_alignment support:
- We pass non-zero align value to DIBuilder only when alignment was forced
- Modify tests to match this change
Differential Revision: https://reviews.llvm.org/D24426
llvm-svn: 284679
LLVM stopped using MDString-based type references, and DIBuilder no
longer fills 'retainedTypes:' with every DICompositeType that has an
'identifier:' field. There are just minor changes to keep the same
behaviour in CFE.
Leaving 'retainedTypes:' unfilled has a dramatic impact on the output
order of the IR though. There are a huge number of testcase changes,
which were unfortunately not really scriptable.
llvm-svn: 267297
Since elements of most kinds of DICompositeType have back references,
most are involved in uniquing cycles. Except via the ODR 'identifier:'
field, which doesn't care about the storage type (see r266549),
they have no hope of being uniqued.
Distinct nodes are far more efficient, so use them for most kinds of
DICompositeType definitions (i.e., when DIType::isForwardDecl is false).
The exceptions:
- DW_TAG_array_type, since their elements never have back-references
and they never have ODR 'identifier:' fields;
- DW_TAG_enumeration_type when there is no ODR 'identifier:' field,
since their elements usually don't have back-references.
This breaks the last major uniquing cycle I'm aware of in the debug info
graph. The impact won't be enormous for C++ because references to
ODR-uniqued nodes still use string-based DITypeRefs; but this should
prevent a regression in C++ when we drop the string-based references.
This wouldn't have been reasonable until r266549, when composite types
stopped relying on being uniqued by structural equivalence to prevent
blow-ups at LTO time.
llvm-svn: 266556
LLVM r236120 renamed debug info IR constructs to use a `DI` prefix, now
that the `DIDescriptor` hierarchy has been gone for about a week. This
commit was generated using the rename-md-di-nodes.sh upgrade script
attached to PR23080, followed by running clang-format-diff.py on the
`lib/` portion of the patch.
llvm-svn: 236121
This reverts commit r220169 which reverted r220153. However, it also
contains additional changes:
- We may need to add padding *after* we've packed the struct. This
occurs when the aligned next field offset is greater than the new
field's offset. When this occurs, we make the struct packed.
*However*, once packed the next field offset might be less than the
new feild's offset. It is in this case that we might further pad the
struct.
- We would pad structs which were perfectly sized! This behavior is
immensely old. This behavior came from blindly subtracting
NextFieldOffsetInChars from RecordSize. This doesn't take into
account the fact that the struct might have a greater overall
alignment than the last field.
llvm-svn: 220175
Plumb through the full QualType of the TemplateArgument::Declaration, as
it's insufficient to only know whether the type is a reference or
pointer (that was necessary for mangling, but insufficient for debug
info). This shouldn't increase the size of TemplateArgument as
TemplateArgument::Integer is still longer by another 32 bits.
Several bits of code were testing that the reference-ness of the
parameters matched, but this seemed to be insufficient (various other
features of the type could've mismatched and wouldn't've been caught)
and unnecessary, at least insofar as removing those tests didn't cause
anything to fail.
(Richard - perchaps you can hypothesize why any of these checks might
need to test reference-ness of the parameters (& explain why
reference-ness is part of the mangling - I would've figured that for the
reference-ness to be different, a prior template argument would have to
be different). I'd be happy to add them in/beef them up and add test
cases if there's a reason for them)
llvm-svn: 219900
Separate out the non-nullable parameters from the nullable ones
(currently only the template template parameter) and demonstrate that
cv-qualifiers aren't preserved for non-null parameters (but are
preserved for null parameters) by adding 'const' to an int* non-type
template parameter.
llvm-svn: 219883
This reverts commit r218917, effectively reapplying r218913. Original
commit message follows.
--
Update debug info testcases for an LLVM metadata schema change to fold
metadata constant operands into a single `MDString`.
Part of PR17891.
llvm-svn: 219011
Update debug info testcases for an LLVM metadata schema change to fold
metadata constant operands into a single `MDString`.
Part of PR17891.
llvm-svn: 218913
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
Seperate the parts related to uuid from debug-info-template.cpp to
debug-info-uuid.cpp since Itanium mangler does not have support for mangling
uuid yet.
Remove -fms-extensions from RUN line of debug-info-template.cpp.
RUN line of debug-info-uuid.cpp has -fms-extensions and -cxx-abi microsoft.
llvm-svn: 189498
David Blaikie