This commit reverts the changes in
https://github.com/llvm/llvm-project/pull/71780 and all of its follow-up
patches.
We got reports of the `.debug_names/.debug_gnu_pubnames/gdb_index/etc.`
sections growing by a non-trivial amount for some large projects. While
GCC emits definitions for static data member constants into the Names
index, they do so *only* for explicitly `constexpr` members. We were
indexing *all* constant-initialized const-static members, which is
likely where the significant size difference comes from. However, only
emitting explicitly `constexpr` variables into the index doesn't seem
like a good way forward, since from clang's perspective `const`-static
integrals are `constexpr` too, and that shouldn't be any different in
the debug-info component. Also, as new code moves to `constexpr` instead
of `const` static for constants, such solution would just delay the
growth of the Names index.
To prevent the size regression we revert to not emitting definitions for
static data-members that have no location.
To support access to such constants from LLDB we'll most likely have to
have to make LLDB find the constants by looking at the containing class
first.
This patch relands https://github.com/llvm/llvm-project/pull/70639
It was reverted because under certain conditions we triggered an
assertion
in `DIBuilder`. Specifically, in the original patch we called
`EmitGlobalVariable`
at the end of `CGDebugInfo::finalize`, after all the temporary `DIType`s
have
been uniqued. With limited debug-info such temporary nodes would be
created
more frequently, leaving us with non-uniqued nodes by the time we got to
`DIBuilder::finalize`; this violated its pre-condition and caused
assertions to trigger.
To fix this, the latest iteration of the patch moves
`EmitGlobalVariable` to the
beginning of `CGDebugInfo::finalize`. Now, when we create a temporary
`DIType` node as a result of emitting a variable definition, it will get
uniqued
in time. A test-case was added for this scenario.
We also now don't emit a linkage name for non-locationed constants since
LLDB doesn't make use of it anyway.
Original commit message:
"""
When an LLDB user asks for the value of a static data member, LLDB
starts
by searching the Names accelerator table for the corresponding variable
definition DIE. For static data members with out-of-class definitions
that
works fine, because those get represented as global variables with a
location
and making them eligible to be added to the Names table. However,
in-class
definitions won’t get indexed because we usually don't emit global
variables
for them. So in DWARF we end up with a single `DW_TAG_member` that
usually holds the constant initializer. But we don't get a corresponding
CU-level `DW_TAG_variable` like we do for out-of-class definitions.
To make it more convenient for debuggers to get to the value of inline
static data
members, this patch makes sure we emit definitions for static variables
with
constant initializers the same way we do for other static variables.
This also aligns
Clang closer to GCC, which produces CU-level definitions for inline
statics and also
emits these into `.debug_pubnames`.
The implementation keeps track of newly created static data members.
Then in `CGDebugInfo::finalize`, we emit a global `DW_TAG_variable` with
a
`DW_AT_const_value` for any of those declarations that didn't end up
with a
definition in the `DeclCache`.
The newly emitted `DW_TAG_variable` will look as follows:
```
0x0000007b: DW_TAG_structure_type
DW_AT_calling_convention (DW_CC_pass_by_value)
DW_AT_name ("Foo")
...
0x0000008d: DW_TAG_member
DW_AT_name ("i")
DW_AT_type (0x00000062 "const int")
DW_AT_external (true)
DW_AT_declaration (true)
DW_AT_const_value (4)
Newly added
vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
0x0000009a: DW_TAG_variable
DW_AT_specification (0x0000008d "i")
DW_AT_const_value (4)
DW_AT_linkage_name ("_ZN2t2IiE1iIfEE")
```
This patch also drops the `DW_AT_const_value` off of the declaration
since we
now always have it on the definition. This ensures that the
`DWARFParallelLinker`
can type-merge class with static members where we couldn't attach the
constant
on the declaration in some CUs.
"""
Dependent changes:
* https://github.com/llvm/llvm-project/pull/71800
This casued asserts:
llvm/lib/IR/Metadata.cpp:689:
void llvm::MDNode::resolve(): Assertion `isUniqued() && "Expected this to be uniqued"' failed.
See comments on the PR.
This also reverts the dependent follow-up commits, see below.
> When an LLDB user asks for the value of a static data member, LLDB
> starts by searching the Names accelerator table for the corresponding
> variable definition DIE. For static data members with out-of-class
> definitions that works fine, because those get represented as global
> variables with a location and making them eligible to be added to the
> Names table. However, in-class definitions won<E2><80><99>t get indexed because
> we usually don't emit global variables for them. So in DWARF we end
> up with a single `DW_TAG_member` that usually holds the constant
> initializer. But we don't get a corresponding CU-level
> `DW_TAG_variable` like we do for out-of-class definitions.
>
> To make it more convenient for debuggers to get to the value of
> inline static data members, this patch makes sure we emit definitions
> for static variables with constant initializers the same way we do
> for other static variables. This also aligns Clang closer to GCC,
> which produces CU-level definitions for inline statics and also
> emits these into `.debug_pubnames`.
>
> The implementation keeps track of newly created static data members.
> Then in `CGDebugInfo::finalize`, we emit a global `DW_TAG_variable`
> with a `DW_AT_const_value` for any of those declarations that didn't
> end up with a definition in the `DeclCache`.
>
> The newly emitted `DW_TAG_variable` will look as follows:
> ```
> 0x0000007b: DW_TAG_structure_type
> DW_AT_calling_convention (DW_CC_pass_by_value)
> DW_AT_name ("Foo")
> ...
>
> 0x0000008d: DW_TAG_member
> DW_AT_name ("i")
> DW_AT_type (0x00000062 "const int")
> DW_AT_external (true)
> DW_AT_declaration (true)
> DW_AT_const_value (4)
>
> Newly added
> vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
>
> 0x0000009a: DW_TAG_variable
> DW_AT_specification (0x0000008d "i")
> DW_AT_const_value (4)
> DW_AT_linkage_name ("_ZN2t2IiE1iIfEE")
> ```
>
> This patch also drops the `DW_AT_const_value` off of the declaration
> since we now always have it on the definition. This ensures that the
> `DWARFParallelLinker` can type-merge class with static members where
> we couldn't attach the constant on the declaration in some CUs.
This reverts commit 7c3707aea8a6f1fc245ad2862982b8a51b6c0fea.
This reverts commit cab0a19467ac2e6e1e022087f4b6cb90d55da040.
This reverts commit 317481b3c8b34b0c3f106c514e6aa39b70886110.
This reverts commit 15fc809404d4715822e5349b76dcca50eb100eec.
This reverts commit 470de2bbec7f5fdd199775aa99c68ac76f4d5c74.
When an LLDB user asks for the value of a static data member, LLDB
starts by searching the Names accelerator table for the corresponding
variable definition DIE. For static data members with out-of-class
definitions that works fine, because those get represented as global
variables with a location and making them eligible to be added to the
Names table. However, in-class definitions won’t get indexed because
we usually don't emit global variables for them. So in DWARF we end
up with a single `DW_TAG_member` that usually holds the constant
initializer. But we don't get a corresponding CU-level
`DW_TAG_variable` like we do for out-of-class definitions.
To make it more convenient for debuggers to get to the value of
inline static data members, this patch makes sure we emit definitions
for static variables with constant initializers the same way we do
for other static variables. This also aligns Clang closer to GCC,
which produces CU-level definitions for inline statics and also
emits these into `.debug_pubnames`.
The implementation keeps track of newly created static data members.
Then in `CGDebugInfo::finalize`, we emit a global `DW_TAG_variable`
with a `DW_AT_const_value` for any of those declarations that didn't
end up with a definition in the `DeclCache`.
The newly emitted `DW_TAG_variable` will look as follows:
```
0x0000007b: DW_TAG_structure_type
DW_AT_calling_convention (DW_CC_pass_by_value)
DW_AT_name ("Foo")
...
0x0000008d: DW_TAG_member
DW_AT_name ("i")
DW_AT_type (0x00000062 "const int")
DW_AT_external (true)
DW_AT_declaration (true)
DW_AT_const_value (4)
Newly added
vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
0x0000009a: DW_TAG_variable
DW_AT_specification (0x0000008d "i")
DW_AT_const_value (4)
DW_AT_linkage_name ("_ZN2t2IiE1iIfEE")
```
This patch also drops the `DW_AT_const_value` off of the declaration
since we now always have it on the definition. This ensures that the
`DWARFParallelLinker` can type-merge class with static members where
we couldn't attach the constant on the declaration in some CUs.
This reverts commit 4909814c08fdf4ec8bd9dad4f157d03de7c3c800.
Following LLDB patch had to be reverted due to Linux test failures:
```
ef3febadf606c2fc4f1ad8d85a7ecdde16e4cbb3
```
Since without that LLDB patch the LLDB tests would fail, revert
this clang patch for now.
When an LLDB user asks for the value of a static data member, LLDB
starts by
searching the Names accelerator table for the corresponding variable
definition
DIE. For static data members with out-of-class definitions that works
fine,
because those get represented as global variables with a location and
making them
eligible to be added to the Names table. However, in-class definitions
won’t get
indexed because we usually don't emit global variables for them. So in
DWARF
we end up with a single `DW_TAG_member` that usually holds the constant
initializer.
But we don't get a corresponding CU-level `DW_TAG_variable` like we do
for
out-of-class definitions.
To make it more convenient for debuggers to get to the value of inline
static data members,
this patch makes sure we emit definitions for static variables with
constant initializers
the same way we do for other static variables. This also aligns Clang
closer to GCC, which
produces CU-level definitions for inline statics and also emits these
into `.debug_pubnames`.
The implementation keeps track of newly created static data members.
Then in
`CGDebugInfo::finalize`, we emit a global `DW_TAG_variable` with a
`DW_AT_const_value` for
any of those declarations that didn't end up with a definition in the
`DeclCache`.
The newly emitted `DW_TAG_variable` will look as follows:
```
0x0000007b: DW_TAG_structure_type
DW_AT_calling_convention (DW_CC_pass_by_value)
DW_AT_name ("Foo")
...
0x0000008d: DW_TAG_member
DW_AT_name ("i")
DW_AT_type (0x00000062 "const int")
DW_AT_external (true)
DW_AT_declaration (true)
DW_AT_const_value (4)
Newly added
vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
0x0000009a: DW_TAG_variable
DW_AT_specification (0x0000008d "i")
DW_AT_const_value (4)
DW_AT_linkage_name ("_ZN2t2IiE1iIfEE")
```
This patch also drops the `DW_AT_const_value` off of the declaration since we now always have it on the definition. This ensures that the `DWARFParallelLinker` can type-merge class with static members where we couldn't attach the constant on the declaration in some CUs.
Reverting to simplify some Google-internal rollout issues. Will recommit
in a week or two.
This reverts commit 517bbc64dbe493644eff8d55fd9566435e930520.
Simplify debug info back to just "limited" or "full" by rolling the ctor
type homing fully into the "limited" debug info.
Also fix a bug I found along the way that was causing ctor type homing
to kick in even when something could be vtable homed (where vtable
homing is stronger/more effective than ctor homing) - fixing at the same
time as it keeps the tests (that were testing only "limited non ctor"
homing and now test ctor homing) passing.
This adds -no-opaque-pointers to clang tests whose output will
change when opaque pointers are enabled by default. This is
intended to be part of the migration approach described in
https://discourse.llvm.org/t/enabling-opaque-pointers-by-default/61322/9.
The patch has been produced by replacing %clang_cc1 with
%clang_cc1 -no-opaque-pointers for tests that fail with opaque
pointers enabled. Worth noting that this doesn't cover all tests,
there's a remaining ~40 tests not using %clang_cc1 that will need
a followup change.
Differential Revision: https://reviews.llvm.org/D123115
Follow-up to fe2dcd89acfd9301a230e38e9030734553baa8dc.
Update test per review comments, restoring the "D" type to its
original state, and adding new "L" type. (Sorry, this was intended to
be included in the prior commit)
Differential Revision: https://reviews.llvm.org/D96044
Previously, the definition was so-marked, but the declaration was
not. This resulted in LLVM's dwarf emission treating the function as
being external, and incorrectly emitting DW_AT_external.
Differential Revision: https://reviews.llvm.org/D96044
arguments.
* Adds 'nonnull' and 'dereferenceable(N)' to 'this' pointer arguments
* Gates 'nonnull' on -f(no-)delete-null-pointer-checks
* Introduces this-nonnull.cpp and microsoft-abi-this-nullable.cpp tests to
explicitly test the behavior of this change
* Refactors hundreds of over-constrained clang tests to permit these
attributes, where needed
* Updates Clang12 patch notes mentioning this change
Reviewed-by: rsmith, jdoerfert
Differential Revision: https://reviews.llvm.org/D17993
This adds the size to forward declared class DITypes, if the size is known.
Fixes an issue where we determine whether to emit fragments based on the
type size, so fragments would sometimes be incorrectly emitted if there
was no size.
Bug: https://bugs.llvm.org/show_bug.cgi?id=47338
Differential Revision: https://reviews.llvm.org/D87062
llvm function is marked nounwind
This fixes cases where an invoke is emitted, despite the called llvm
function being marked nounwind, because ConstructAttributeList failed to
add the attribute to the attribute list. llvm optimization passes turn
invokes into calls and optimize away the exception handling code, but
it's better to avoid emitting the code in the front-end if the called
function is known not to raise an exception.
Differential Revision: https://reviews.llvm.org/D83906
(this would regress size without a corresponding LLVM change that avoids
putting other user defined types inside type units when they aren't in
their own type units - instead emitting declarations inside the type
unit and a definition in the primary CU)
Reviewers: aprantl
Differential Revision: https://reviews.llvm.org/D61079
llvm-svn: 359235
In C++11, a destructor's implicit exception-spec is nothrow.
The IR for the destructor's invocation changed from invoke to call.
Differential Revision: https://reviews.llvm.org/D28425
llvm-svn: 291458
This seems like it must've been a leftover by accident - no tests were
backing it up & it doesn't make much sense to include size/alignment on
class declarations (it'd only be on those declarations for which the
definition was available - otherwise the size/alignment would not be
known).
llvm-svn: 290631
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
Summary:
This flag is enabled by default in the driver when NDEBUG is set. It
is forwarded on the LLVMContext to discard all value names (but
GlobalValue) for performance purpose.
This an improved version of D18024
Reviewers: echristo, chandlerc
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D18127
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 263394
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 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
These members will still be lazily added to the relevant DWARF DIEs in
LLVM but when enumerating the members they will not appear. This allows
DWARF type units to be more consistent - the type unit will never
contain these special members (so all instances of the type should have
the same DIEs without some having some special members and others having
others) and the special members will be added to the skeletal
declaration that appears in the relevant compile_unit.
llvm-svn: 197844
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
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
This might be able to be optimized further by only doing this in the
absence of a key function, but it doesn't look like GCC is doing that so
I'm not rushing to do it just yet.
llvm-svn: 189022
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
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
- Relax a expression for arm-gnueabi.
- Exclude msvc to limit target triplets to add limited a few targets.
Feel free to remove actions if guys thought they redundant.
llvm-svn: 174278
r173593 made us a little too eager to associate all code at the end of a
function with the user-written 'return' line. This caused problems with
breakpoints as they'd be set in exception handling code preceeding the
actual non-exception return handling code, leading to the breakpoint never
being hit in non-exceptional execution.
This change restores the pre-r173593 exception handling line information where
the cleanup code is associated with the '}' not the return line.
llvm-svn: 174206
