This is handy for some AutoFDO stuff, and seems like a minor improvement
to correctness (otherwise a debug info consumer might think the decl
line/file of the def was the same as that of the declaration - though
what a consumer might use that for, I'm not sure - maybe "list <func>"
would've misbehaved with the old behavior?) and at a minor cost (in my
experiment, with fission, without type units, without compression, 0.01%
growth in debug info in the executable/objects, 0.02% growth in the .dwo
files).
llvm-svn: 249487
Currently the DWARF backend requires that subprograms have a type, and
the type is ignored if it has an empty type array. The long term
direction here -- see PR23079 -- is instead to skip the type entirely if
there's no valid type.
It turns out we have cases in tree of missing types on subprograms, but
since they're not referenced by compile units, the backend never crashes
on them. One option would be to add a Verifier check that subprograms
have types, and fix the bitrot. However, this is a fair bit of churn
(20-30 testcases) that would be reversed anyway by PR23079.
I found this inconsistency because of a WIP patch and upgrade script for
PR23367 that started crashing on test/DebugInfo/2010-10-01-crash.ll.
This commit updates the testcase to reference the subprogram from the
compile unit, and fixes the resulting crash (in line with the direction
of PR23079). This also updates `DIBuilder` to stop assuming a non-null
pointer for the subroutine types.
llvm-svn: 246333
Mangled "linkage" names can be huge, and if the debugger (or other
tools) have no use for them, the size savings can be very impressive
(on the order of 40%).
Add one test for controlling behavior, and modify a number of tests to
either stop using linkage names, or make llc emit them (so these tests
will still run when the default triple is for PS4).
Differential Revision: http://reviews.llvm.org/D11374
llvm-svn: 244678
Remove the fake `DW_TAG_auto_variable` and `DW_TAG_arg_variable` tags,
using `DW_TAG_variable` in their place Stop exposing the `tag:` field at
all in the assembly format for `DILocalVariable`.
Most of the testcase updates were generated by the following sed script:
find test/ -name "*.ll" -o -name "*.mir" |
xargs grep -l 'DILocalVariable' |
xargs sed -i '' \
-e 's/tag: DW_TAG_arg_variable, //' \
-e 's/tag: DW_TAG_auto_variable, //'
There were only a handful of tests in `test/Assembly` that I needed to
update by hand.
(Note: a follow-up could change `DILocalVariable::DILocalVariable()` to
set the tag to `DW_TAG_formal_parameter` instead of `DW_TAG_variable`
(as appropriate), instead of having that logic magically in the backend
in `DbgVariable`. I've added a FIXME to that effect.)
llvm-svn: 243774
Instead of the pattern
for (auto I = x.rbegin(), E = x.end(); I != E; ++I)
we can use make_range to construct the reverse range and iterate using
that instead.
llvm-svn: 243163
`DISubroutineType` is impossible at this `dyn_cast` site, since we're
only dealing with named types and `DISubroutineType` cannot be named.
Strengthen the `dyn_cast` to `DICompositeType`.
llvm-svn: 243157
Refactor `isUnsignedDIType()` to deal with `DICompositeType` explicitly.
Since `DW_TAG_subroutine_type` isn't handled here (the assertions about
tags rule it out), this allows strengthening the `dyn_cast` to
`DIDerivedType`.
Besides making the code clearer, this it removes a use of
`DIDerivedTypeBase`.
llvm-svn: 243148
There is an assertion inside `DICompositeTypeBase::getElements()` that
`this` is not a `DISubroutineType`, leaving only `DICompositeType`.
Make that clear at the call sites.
llvm-svn: 243134
This is a necessary prerequisite for bootstrapping the emission
of debug info inside modules.
- Adds a FlagExternalTypeRef to DICompositeType.
External types must have a unique identifier.
- External type references are emitted using a forward declaration
with a DW_AT_signature([DW_FORM_ref_sig8]) based on the UID.
http://reviews.llvm.org/D9612
llvm-svn: 242302
Function static variables, typedefs and records (class, struct or union) declared inside
a lexical scope were associated with the function as their parent scope, rather than the
lexical scope they are defined or declared in.
This fixes PR19238
Patch by: amjad.aboud@intel.com
Differential Revision: http://reviews.llvm.org/D9758
llvm-svn: 241153
the DW_AT_bit_offset computation, the byte offset is in fact also
endian-dependent as it needs to point to the storage unit containing the
most-significant bit of the the bitfield.
I'm so looking forward to emitting the endian-agnostic DWARF 3 version
instead.
llvm-svn: 240890
Replace the `std::vector<>` for `DIE::Children` with an intrusively
linked list. This is a strict memory improvement: it requires no
auxiliary storage, and reduces `sizeof(DIE)` by one pointer. It also
factors out the DIE-related malloc traffic.
This drops llc memory usage from 735 MB down to 718 MB, or ~2.3%.
(I'm looking at `llc` memory usage on `verify-uselistorder.lto.opt.bc`;
see r236629 for details.)
llvm-svn: 240736
Change `DIE::Values` to a singly linked list, where each node is
allocated on a `BumpPtrAllocator`. In order to support `push_back()`,
the list is circular, and points at the tail element instead of the
head. I abstracted the core list logic out to `IntrusiveBackList` so
that it can be reused for `DIE::Children`, which also cares about
`push_back()`.
This drops llc memory usage from 799 MB down to 735 MB, about 8%.
(I'm looking at `llc` memory usage on `verify-uselistorder.lto.opt.bc`;
see r236629 for details.)
llvm-svn: 240733
Different object formats represent references from dwarf in different ways.
ELF uses a relocation to the referenced point (except for .dwo) and
COFF/MachO use the offset of the referenced point inside its section.
This patch renames emitSectionOffset because
* It doesn't produce an offset on ELF.
* It changes behavior depending on how DWARF is represented, so adding
dwarf to its name is probably a good thing.
The patch also adds an option to force the use of offsets.That avoids
funny looking code like
if (!UseOffsets)
Asm->emitSectionOffset....
It was correct, but read as if the ! was inverted.
llvm-svn: 239866
Change `DIE::addChild()` to return a reference to the just-added node,
and update consumers to use it directly. An upcoming commit will
abstract away (and eventually change) the underlying storage of
`DIE::Children`.
llvm-svn: 238372
This reverts commit r238350, effectively reapplying r238349 after fixing
(all?) the problems, all somehow related to how I was using
`AlignedArrayCharUnion<>` inside `DIEValue`:
- MSVC can only handle `sizeof()` on types, not values. Change the
assert.
- GCC doesn't know the `is_trivially_copyable` type trait. Instead of
asserting it, add destructors.
- Call placement new even when constructing POD (i.e., the pointers).
- Instead of copying the char buffer, copy the casted classes.
I've left in a couple of `static_assert`s that I think both MSVC and GCC
know how to handle. If the bots disagree with me, I'll remove them.
- Check that the constructed type is either standard layout or a
pointer. This protects against a programming error: we really want
the "small" `DIEValue`s to be small and simple, so don't
accidentally change them not to be.
- Similarly, check that the size of the buffer is no bigger than a
`uint64_t` or a pointer. (I thought checking against
`sizeof(uint64_t)` would be good enough, but Chandler suggested that
pointers might sometimes be bigger than that in the context of
sanitizers.)
I've also committed r238359 in the meantime, which introduces a
DIEValue.def to simplify dispatching between the various types (thanks
to a review comment by David Blaikie). Without that, this commit would
be almost unintelligible.
Here's the original commit message:
--
Change `DIEValue` to be stored/passed/etc. by value, instead of
reference. It's now a discriminated union, with a `Val` field storing
the actual type. The classes that used to inherit from `DIEValue` no
longer do. There are two categories of these:
- Small values fit in a single pointer and are stored by value.
- Large values require auxiliary storage, and are stored by reference.
The only non-mechanical change is to tools/dsymutil/DwarfLinker.cpp. It
was relying on `DIEInteger`s being passed around by reference, so I
replaced that assumption with a `PatchLocation` type that stores a safe
reference to where the `DIEInteger` lives instead.
This commit causes a temporary regression in memory usage, since I've
left merging `DIEAbbrevData` into `DIEValue` for a follow-up commit. I
measured an increase from 845 MB to 879 MB, around 3.9%. The follow-up
drops it lower than the starting point, and I've only recently brought
the memory this low anyway, so I'm committing these changes separately
to keep them incremental. (I also considered swapping the commits, but
the other one first would cause a lot more code churn.)
(I'm looking at `llc` memory usage on `verify-uselistorder.lto.opt.bc`;
see r236629 for details.)
--
llvm-svn: 238362
This reverts commit r238349, since it caused some errors on bots:
- std::is_trivially_copyable isn't available until GCC 5.0.
- It was complaining about strict aliasing with my use of
ArrayCharUnion.
llvm-svn: 238350
Change `DIEValue` to be stored/passed/etc. by value, instead of
reference. It's now a discriminated union, with a `Val` field storing
the actual type. The classes that used to inherit from `DIEValue` no
longer do. There are two categories of these:
- Small values fit in a single pointer and are stored by value.
- Large values require auxiliary storage, and are stored by reference.
The only non-mechanical change is to tools/dsymutil/DwarfLinker.cpp. It
was relying on `DIEInteger`s being passed around by reference, so I
replaced that assumption with a `PatchLocation` type that stores a safe
reference to where the `DIEInteger` lives instead.
This commit causes a temporary regression in memory usage, since I've
left merging `DIEAbbrevData` into `DIEValue` for a follow-up commit. I
measured an increase from 845 MB to 879 MB, around 3.9%. The follow-up
drops it lower than the starting point, and I've only recently brought
the memory this low anyway, so I'm committing these changes separately
to keep them incremental. (I also considered swapping the commits, but
the other one first would cause a lot more code churn.)
(I'm looking at `llc` memory usage on `verify-uselistorder.lto.opt.bc`;
see r236629 for details.)
llvm-svn: 238349
Expose the `DwarfStringPool` entry in a header, and store a pointer to
it directly in `DIEString`. Instead of choosing at creation time how to
emit it, use the `dwarf::Form` to determine that at emission time.
Besides avoiding the other `DIEValue`, this shaves two pointers off of
`DIEString`; the data is now a single pointer. This is a nice cleanup
on its own -- and drops memory usage from 861 MB down to 853 MB, around
0.9% -- but it's also preparation for passing `DIEValue`s by value.
(I'm looking at `llc` memory usage on `verify-uselistorder.lto.opt.bc`;
see r236629 for details.)
llvm-svn: 238117
Change `DwarfStringPool` to calculate byte offsets on-the-fly, and
update `DwarfUnit::getLocalString()` to use a `DIEInteger` instead of a
`DIEDelta` when Dwarf doesn't use relocations (i.e., Mach-O). This
eliminates another call to `EmitLabelDifference()`, and drops memory
usage from 865 MB down to 861 MB, around 0.5%.
(I'm looking at `llc` memory usage on `verify-uselistorder.lto.opt.bc`;
see r236629 for details.)
llvm-svn: 238114
This starts merging MCSection and MCSectionData.
There are a few issues with the current split between MCSection and
MCSectionData.
* It optimizes the the not as important case. We want the production
of .o files to be really fast, but the split puts the information used
for .o emission in a separate data structure.
* The ELF/COFF/MachO hierarchy is not represented in MCSectionData,
leading to some ad-hoc ways to represent the various flags.
* It makes it harder to remember where each item is.
The attached patch starts merging the two by moving the alignment from
MCSectionData to MCSection.
Most of the patch is actually just dropping 'const', since
MCSectionData is mutable, but MCSection was not.
llvm-svn: 237936
This reverts commit 0037b6bcbc874aa1b93d7ce3ad8dba3753ee2d9d (r237827).
David Blaikie suggested some alternatives to this which are better. Reverting to apply a better solution later.
llvm-svn: 237849
DebugLocDwarfExpression::EmitOp was creating temporary strings by concatenating Twine's.
When emitting to object files, these comments are thrown away.
This commit adds a boolean to the constructor of the DwarfExpression to control whether it will actually emit
any comments. This prevents it from even generating the temporary comments which would have been thrown away anyway.
llvm-svn: 237827
Finish off PR23080 by renaming the debug info IR constructs from `MD*`
to `DI*`. The last of the `DIDescriptor` classes were deleted in
r235356, and the last of the related typedefs removed in r235413, so
this has all baked for about a week.
Note: If you have out-of-tree code (like a frontend), I recommend that
you get everything compiling and tests passing with the *previous*
commit before updating to this one. It'll be easier to keep track of
what code is using the `DIDescriptor` hierarchy and what you've already
updated, and I think you're extremely unlikely to insert bugs. YMMV of
course.
Back to *this* commit: I did this using the rename-md-di-nodes.sh
upgrade script I've attached to PR23080 (both code and testcases) and
filtered through clang-format-diff.py. I edited the tests for
test/Assembler/invalid-generic-debug-node-*.ll by hand since the columns
were off-by-three. It should work on your out-of-tree testcases (and
code, if you've followed the advice in the previous paragraph).
Some of the tests are in badly named files now (e.g.,
test/Assembler/invalid-mdcompositetype-missing-tag.ll should be
'dicompositetype'); I'll come back and move the files in a follow-up
commit.
llvm-svn: 236120
Remove the `DIArray` and `DITypeArray` typedefs, preferring the
underlying types (`DebugNodeArray` and `MDTypeRefArray`, respectively).
llvm-svn: 235413
Delete subclasses of (the already deleted) `DIType` in favour of
directly using pointers from the `Metadata` hierarchy.
While `DICompositeType` wraps `MDCompositeTypeBase` and `DIDerivedType`
wraps `MDDerivedTypeBase`, most uses of each really meant the more
specific `MDCompositeType` and `MDDerivedType`.
llvm-svn: 235351
The version of `constructTypeDIE()` for `MDSubroutineType` is unrelated
to (and has different callers than) the `MDCompositeType`. Split the
two in half.
This simplifies an upcoming patch to delete `DICompositeType`. There
shouldn't be any real functionality change here. `createTypeDIE()` is
`cast<>`'ing where it didn't need to before, but that function in turn
is only called for true `MDCompositeType`s.
llvm-svn: 235349
Update comment style in `DwarfUnit`.
- Drop duplicated comments at definition, and update the comments at
the declaration where the definition comments looked newer or more
complete.
- Drop the `functionName -` prefix.
- Add `\brief` in a few places.
- Remove a few comments entirely that weren't adding value (just
turned the function name and arguments into a sentence).
llvm-svn: 235345
This is the last major parent class, so I'll probably start deleting
classes in batches now. Looks like many of the references to the DI*
hierarchy were updated organically along the way.
llvm-svn: 235331
Replace uses of `DIScope` with `MDScope*`. There was one spot where
I've left an `MDScope*` uninitialized (where `DIScope` would have been
default-initialized to `nullptr`) -- this is intentional, since the
if/else that follows should unconditional assign it to a value.
llvm-svn: 235327
PR23080 is almost finished. With this commit, there's no consequential
API in `DIDescriptor` and its subclasses. What's left?
- Default-constructed to `nullptr`.
- Handy `const_cast<>` (constructed from `const`, but accessors are
non-`const`).
I think the safe way to catch those is to delete the classes and fix
compile errors. That'll be my next step, after I delete the `DITypeRef`
(etc.) wrapper around `MDTypeRef`.
llvm-svn: 235069
Continuing PR23080, gut `DIType` and its various subclasses, leaving
behind thin wrappers around the pointer types in the new debug info
hierarchy.
llvm-svn: 235064
Remove the accessors of `DIDerivedType` that downcast to
`MDDerivedType`, shifting the `cast<MDDerivedType>` into the callers.
Also remove `DIType::isValid()`, which is really just a check against
`nullptr` at this point.
llvm-svn: 235059
Gut the `DIDescriptor` wrappers around `MDLocalScope` subclasses. Note
that `DILexicalBlock` wraps `MDLexicalBlockBase`, not `MDLexicalBlock`.
llvm-svn: 234850
Gut all the non-pointer API from the variable wrappers, except an
implicit conversion from `DIGlobalVariable` to `DIDescriptor`. Note
that if you're updating out-of-tree code, `DIVariable` wraps
`MDLocalVariable` (`MDVariable` is a common base class shared with
`MDGlobalVariable`).
llvm-svn: 234840