Commit Graph

447 Commits

Author SHA1 Message Date
David Blaikie 029bd3350e Recommit r212203: Don't try to construct debug LexicalScopes hierarchy for functions that do not have top level debug information.
Reverted by Eric Christopher (Thanks!) in r212203 after Bob Wilson
reported LTO issues. Duncan Exon Smith and Aditya Nandakumar helped
provide a reduced reproduction, though the failure wasn't too hard to
guess, and even easier with the example to confirm.

The assertion that the subprogram metadata associated with an
llvm::Function matches the scope data referenced by the DbgLocs on the
instructions in that function is not valid under LTO. In LTO, a C++
inline function might exist in multiple CUs and the subprogram metadata
nodes will refer to the same llvm::Function. In this case, depending on
the order of the CUs, the first intance of the subprogram metadata may
not be the one referenced by the instructions in that function and the
assertion will fail.

A test case (test/DebugInfo/cross-cu-linkonce-distinct.ll) is added, the
assertion removed and a comment added to explain this situation.

Original commit message:

If a function isn't actually in a CU's subprogram list in the debug info
metadata, ignore all the DebugLocs and don't try to build scopes, track
variables, etc.

While this is possibly a minor optimization, it's also a correctness fix
for an incoming patch that will add assertions to LexicalScopes and the
debug info verifier to ensure that all scope chains lead to debug info
for the current function.

Fix up a few test cases that had broken/incomplete debug info that could
violate this constraint.

Add a test case where this occurs by design (inlining a
debug-info-having function in an attribute nodebug function - we want
this to work because /if/ the nodebug function is then inlined into a
debug-info-having function, it should be fine (and will work fine - we
just stitch the scopes up as usual), but should the inlining not happen
we need to not assert fail either).

llvm-svn: 212649
2014-07-09 21:02:41 +00:00
Eric Christopher 09f7131984 Temporarily revert "Don't try to construct debug LexicalScopes hierarchy for functions that do not have top level debug information." as it appears to be breaking some LTO constructs.
This reverts commit r212203.

llvm-svn: 212298
2014-07-03 22:24:54 +00:00
David Blaikie d47fb5b339 Don't try to construct debug LexicalScopes hierarchy for functions that do not have top level debug information.
If a function isn't actually in a CU's subprogram list in the debug info
metadata, ignore all the DebugLocs and don't try to build scopes, track
variables, etc.

While this is possibly a minor optimization, it's also a correctness fix
for an incoming patch that will add assertions to LexicalScopes and the
debug info verifier to ensure that all scope chains lead to debug info
for the current function.

Fix up a few test cases that had broken/incomplete debug info that could
violate this constraint.

Add a test case where this occurs by design (inlining a
debug-info-having function in an attribute nodebug function - we want
this to work because /if/ the nodebug function is then inlined into a
debug-info-having function, it should be fine (and will work fine - we
just stitch the scopes up as usual), but should the inlining not happen
we need to not assert fail either).

llvm-svn: 212203
2014-07-02 18:31:35 +00:00
Adrian Prantl da7d92e3e2 Debug info: split out complex DIVariable address expressions into a
separate MDNode so they can be uniqued via folding set magic. To conserve
space, DIVariable nodes are still variable-length, with the last two
fields being optional.

No functional change.
http://reviews.llvm.org/D3526

llvm-svn: 212050
2014-06-30 17:17:35 +00:00
Rafael Espindola 6804d450cd Fix another asserting method in the null streamer.
llvm-svn: 211668
2014-06-25 05:37:58 +00:00
David Blaikie 6800e39865 Fix up scoping in a few tests (and delete one that validates unnecessary behavior).
Most of this is just tests that were silently succeeding in spite of
schema changes I made over a year ago. Cleaning them up as they lead to
failures in a change I'm working on/will come soon.

test/DebugInfo/2010-01-19-DbgScope.ll was removed as it tested miscoping
where a DebugLoc described a location not in the current function. The
test case doesn't describe why this is a valid situation and should be
supported, so I'm removing it and shortly going to commit changes that
make this firmly unsupported/assert-fail.

llvm-svn: 211628
2014-06-24 20:10:27 +00:00
David Blaikie de8e12a49a DebugInfo: Fission: Ensure the address pool entries for location lists are emitted.
The address pool was being emitted before location lists. The latter
could add more entries to the pool which would be lost/never emitted.

llvm-svn: 211284
2014-06-19 17:59:14 +00:00
Louis Gerbarg 343f5cdfad Allow X86FastIsel to cope with 64 bit absolute relocations
This patch is a follow up to r211040 & r211052. Rather than bailing out of fast
isel this patch will generate an alternate instruction (movabsq) instead of the
leaq. While this will always have enough room to handle the 64 bit displacment
it is generally over kill for internal symbols (most displacements will be
within 32 bits) but since we have no way of communicating the code model to the
the assmebler in order to avoid flagging an absolute leal/leaq as illegal when
using a symbolic displacement.

llvm-svn: 211130
2014-06-17 23:22:41 +00:00
Louis Gerbarg dcf00251ea Improve comments for r211040
Added comment to clarify why we r211040 choose to bail out of fast isel instead
of generating a more complicated relocation, and fix mislabelled register in the
comments of the asan test case.

llvm-svn: 211052
2014-06-16 20:31:50 +00:00
Louis Gerbarg a5360c4cd8 Fix illegal relocations in X86FastISel
On x86_86  the lea instruction can only use a 32 bit immediate value. When
the code is compiled statically the RIP register is not used, meaning the
immediate is all that can be used for the relocation, which is not sufficient
in the case of targets more than +/- 2GB away. This patch bails out of fast
isel in those cases and reverts to DAG which does the right thing.

Test case included.

llvm-svn: 211040
2014-06-16 17:35:40 +00:00
David Blaikie e847f132f7 DebugInfo: Reference abstract definitions from variables in concrete definitions that preceed their first inline definition.
Rather than relying on abstract variables looked up at the time the
concrete variable is created, look them up at the end of the module to
ensure they're referenced even if they're created after the concrete
definition. This completes/matches the work done in r209677 to handle
this for the subprograms themselves.

llvm-svn: 210946
2014-06-13 22:35:44 +00:00
David Blaikie eb1a27239c DebugInfo: Following up to r209677, refactor local variable emission to delay the choice between emitting the definition attributes or using DW_AT_abstract_definition
This doesn't fix the abstract variable handling yet, but it introduces a
similar delay mechanism as was added for subprograms, causing
DW_AT_location to be reordered to the beginning of the attribute list
for local variables, and fixes all the test fallout for that.

A subsequent commit will remove the abstract variable handling in
DbgVariable and just do the abstract variable lookup at module end to
ensure that abstract variables introduced after their concrete
counterparts are appropriately referenced by the concrete variable.

llvm-svn: 210943
2014-06-13 22:18:23 +00:00
David Blaikie 04ed1d1b68 DebugInfo: Refactor some tests to allow DW_AT_name to not be the first attribute in a local variable.
In an effort to fix concrete variables referencing abstract origins
where the concrete variable preceeds the first inlined usage, the
addition of attributes such as name, file, etc will be delayed until the
end of the module (to wait to see if any inlined instances have
occurred, thus necessitating an abstract definition that the concrete
definition should also reference).

These test cases don't actually need to care about this ordering of
attributes, so update them to be more resilient to such changes coming
in the near future.

llvm-svn: 210940
2014-06-13 21:52:33 +00:00
David Blaikie be315b63e2 test/DebugInfo/X86/dbg-value-isel.s: correct lexical block descriptor to match schema
This silently broke a long time ago when I unified some aspects of the
debug info schema. I'm just cleaning these up if/when they become a
problem.

llvm-svn: 210939
2014-06-13 21:52:28 +00:00
Alp Toker d3d017cf00 Reduce verbiage of lit.local.cfg files
We can just split targets_to_build in one place and make it immutable.

llvm-svn: 210496
2014-06-09 22:42:55 +00:00
Alexey Samsonov 8000e2734e Generate better location ranges for some register-described variables.
Don't terminate location ranges for register-described variables
at the end of machine basic block if this register is never modified
in the function body, except for the prologue and epilogue. Prologue
location is guessed by FrameSetup flags on MachineInstructions, while
epilogue location is deduced from debug locations of instructions
in the basic blocks ending with return instructions.

This patch is mostly targeted to fix non-trivial debug locations for
variables addressed via stack and frame pointers.

It is not really a generic fix. We can still produce poor debug info
for register-described variables if this register *is* modified somewhere
in the function, but in unrelated places. This might be the case for the debug
info in optimized binaries (e.g. for local variables in inlined functions).
LiveDebugVariables pass in CodeGen attempts to fix this problem by adjusting
DBG_VALUE instructions, but this pass is tied to greedy register allocator,
which is used in optimized builds only. Proper fix would likely involve
generalizing LiveDebugVariables to all register allocators. See more discussion
in http://reviews.llvm.org/D3933 review thread.

I'm proceeding with this patch to fix immediate severe problems and
important cases, e.g. fix completely broken debug info with AddressSanitizer
and fix PR19307 (missing debug info for by-value std::string arguments).

llvm-svn: 210492
2014-06-09 21:53:47 +00:00
Alp Toker 5c53639492 Fix typos
llvm-svn: 210401
2014-06-07 21:23:09 +00:00
David Blaikie 3dca59902b DebugInfo: Use the scope of the function declaration, if any, to name a function in DWARF pubnames
This ensures that member functions, for example, are entered into
pubnames with their fully qualified name, rather than inside the global
namespace.

llvm-svn: 210379
2014-06-06 22:29:05 +00:00
David Blaikie 553eb4a880 DebugInfo: pubnames: include file-local (static or anonymous namespace) variables and anonymous namespaces themselves.
Still some issues with name qualification, FIXMEs added to test cases
and fixes will come next.

llvm-svn: 210378
2014-06-06 22:16:56 +00:00
David Blaikie fcf31a73d1 Match the full hex offsets in test/DebugInfo/X86/gnu-public-names.ll
These checks were accidentally skipping the 0x prefix in the hex
offsets, then cunningly ignoring the prefix in the use of those captured
values.

Except in the case of the unit length, where the match was only matching
the leading '0' before the x in the 0x prefix, then matching that
against the length. We can't actually express the length association
here, as the length field in the Compile Unit header does not include
the length field itself, but the length field in the pubnames section
/does/ include the size of the length field in the Compile Unit header -
so the two numbers are actually 4 bytes different. Just skip matching
that.

llvm-svn: 210364
2014-06-06 18:45:14 +00:00
David Blaikie 941644d1bb Remove DWARF3 testing of test/DebugInfo/X86/gnu-public-names.ll
This was added to test that DW_AT_GNU_pubnames used sec_offset in DWARF4
and data4 in DWARF3 and below. Since then we've updated
DW_AT_GNU_pubnames to be a flag, rather than a section offset anyway.

Granted this still differs between DWARF 3 and DWARF 4
(FORM_flag_present versun FORM_flag) but it doesn't seem worthwhile
testing that codepath again here. It's covered adequately in many other
test cases.

And while I'm here, don't hardcode the byte size of the compile unit -
it's not relevant to this test and just makes it brittle if/when
anything changes in the way this CU is emitted.

llvm-svn: 210362
2014-06-06 18:22:04 +00:00
Alp Toker da0c7933cf Fix typos
llvm-svn: 209982
2014-05-31 21:26:28 +00:00
David Blaikie 482097d098 DebugInfo: Create abstract function definitions even when concrete definitions preceed inline definitions.
After much puppetry, here's the major piece of the work to ensure that
even when a concrete definition preceeds all inline definitions, an
abstract definition is still created and referenced from both concrete
and inline definitions.

Variables are still broken in this case (see comment in
dbg-value-inlined-parameter.ll test case) and will be addressed in
follow up work.

llvm-svn: 209677
2014-05-27 18:37:55 +00:00
David Blaikie 3c2fff3fe6 DebugInfo: Lazily construct subprogram definition DIEs.
A further step to correctly emitting concrete out of line definitions
preceeding inlined instances of the same program.

To do this, emission of subprograms must be delayed until required since
we don't know which (abstract only (if there's no out of line
definition), concrete only (if there are no inlined instances), or both)
DIEs are required at the start of the module.

To reduce the test churn in the following commit that actually fixes the
bug, this commit introduces the lazy DIE construction and cleans up test
cases that are impacted by the changes in the resulting DIE ordering.

llvm-svn: 209675
2014-05-27 18:37:48 +00:00
David Blaikie f7221adb8e DebugInfo: Lazily attach definition attributes to definitions.
This is a precursor to fixing inlined debug info where the concrete,
out-of-line definition may preceed any inlined usage. To cope with this,
the attributes that may appear on the concrete definition or the
abstract definition are delayed until the end of the module. Then, if an
abstract definition was created, it is referenced (and no other
attributes are added to the out-of-line definition), otherwise the
attributes are added directly to the out-of-line definition.

In a couple of cases this causes not just reordering of attributes, but
reordering of types. When the creation of the attribute is delayed, if
that creation would create a type (such as for a DW_AT_type attribute)
then other top level DIEs may've been constructed during the delay,
causing the referenced type to be created and added after those
intervening DIEs. In the extreme case, in cross-cu-inlining.ll, this
actually causes the DW_TAG_basic_type for "int" to move from one CU to
another.

llvm-svn: 209674
2014-05-27 18:37:43 +00:00
David Blaikie 66c3077470 DebugInfo: Fix argument ordering in test by adding argument numbering.
This old test didn't have the argument numbering that's now squirelled
away in the high bits of the line number in the DW_TAG_arg_variable
metadata.

Add the numbering and update the test to ensure arguments are in-order.

llvm-svn: 209669
2014-05-27 17:57:14 +00:00
David Blaikie 69d3406a2d Streamline test case by avoiding a temporary file and piping llc output straight to llvm-dwarfdump
We still do temporary files in many cases, just updating this particular
one because I was debugging it and made this change while doing so.

llvm-svn: 209601
2014-05-25 15:38:52 +00:00
David Blaikie 2f75351c02 DebugInfo: Generalize some tests to handle variations in attribute ordering.
In an effort to fix inlined debug info in situations where the out of
line definition of a function preceeds any inlined usage, the order in
which some attributes are added to subprogram DIEs may change. (in
essence, definition-necessary attributes like DW_AT_low_pc/high_pc will
be added immediately, but the names, types, and other features will be
delayed to module end where they may either be added to the subprogram
DIE or instead reference an abstract definition for those values)

These tests can be generalized to be resilient to this change. 5 or so
tests actually have to be incompatibly changed to cope with this
reordering and will go along with the change that affects the order.

llvm-svn: 209554
2014-05-23 21:11:46 +00:00
David Blaikie 71ed20f671 DebugInfo: Generalize a test case to not depend on abbreviation numbering.
It's an unnecessary detail for this test and just gets in the way when
making unrelated changes to the output in this test.

llvm-svn: 209553
2014-05-23 21:07:01 +00:00
David Blaikie 2da282b860 Revert "DebugInfo: Don't put fission type units in comdat sections."
This reverts commit r208930, r208933, and r208975.

It seems not all fission consumers are ready to handle this behavior.
Reverting until tools are brought up to spec.

llvm-svn: 209338
2014-05-21 23:27:41 +00:00
David Blaikie 825bdd2fc6 DebugInfo: Ensure concrete out of line variables from inlined functions reference their abstract origins.
llvm-svn: 209327
2014-05-21 22:41:17 +00:00
David Blaikie ce7a1bd038 DebugInfo: Simplify subprogram declaration creation/references and accidentally refix PR11300.
Also simplifies the linkage name handling a little too.

llvm-svn: 209311
2014-05-21 18:04:33 +00:00
Eric Christopher a6342c581e Add a comment here.
llvm-svn: 209262
2014-05-21 00:02:50 +00:00
Eric Christopher 12a7155f60 Move this test to the backend from the frontend.
llvm-svn: 209259
2014-05-20 23:59:54 +00:00
Eric Christopher 2feed5fd68 Move the function and data section flags into the options struct and
make the functions to set them non-static.
Move and rename the llvm specific backend options to avoid conflicting
with the clang option.

Paired with a backend commit to update.

llvm-svn: 209238
2014-05-20 21:25:34 +00:00
David Blaikie 424b59b1ce DebugInfo: Assume all subprogram DIEs have been created before any abstract subprograms are constructed.
Since we visit the whole list of subprograms for each CU at module
start, this is clearly true - don't test for the case, just assert it.

A few old test cases seemed to have incomplete subprogram lists, but any
attempt to reproduce them shows full subprogram lists that even include
entities that have been completely inlined and the out of line
definition removed.

llvm-svn: 209178
2014-05-19 23:16:19 +00:00
David Blaikie 973141a035 DebugInfo: Don't include DW_AT_inline on each abstract definition multiple times.
When I refactored this in r208636 I accidentally caused this to be added
multiple times to each abstract subprogram (not accounting for the
deduplicating effect of the InlinedSubprogramDIEs set).

This got better in r208798 when the abstract definitions got the
attribute added to them at construction time, but still had the
redundant copies introduced in r208636.

This commit removes those excess DW_AT_inlines and relies solely on the
insertion in r208798.

llvm-svn: 209166
2014-05-19 22:07:16 +00:00
David Blaikie 48b056bab0 DebugInfo: Fix missing inlined_subroutines caused by r208748.
The check in DwarfDebug::constructScopeDIE was meant to consider inlined
subroutines as any non-top-level scope that was a subprogram. Instead of
checking "not top level scope" it was checking if the /subprogram's/
scope was non-top-level.

Fix this and beef up a test case to demonstrate some of the missing
inlined_subroutines are no longer missing.

In the course of fixing this I also found that r208748 (with this fix)
found one /extra/ inlined_subroutine in concrete_out_of_line.ll due to
two inlined_subroutines having the same inlinedAt location. The previous
implementation was collapsing these into a single inlined subroutine.

I'm not sure what the original code was that created this .ll file so
I'm not sure if this actually happens in practice today. Since we
deliberately include column information to disambiguate two calls on the
same line, that may've addressed this bug in the frontend, but it's good
to know that workaround isn't necessary for this particular case
anymore.

llvm-svn: 209165
2014-05-19 21:54:31 +00:00
David Blaikie 825f487b68 DebugInfo: Assume the CU's Subprogram list only contains definitions.
DIBuilder maintains this invariant and the current DwarfDebug code could
end up doing weird things if it contained declarations (such as putting
the definition DIE inside a CU that contained the declaration - this
doesn't seem like a good idea, so rather than adding logic to handle
this case we'll just ban in for now & cross that bridge if we come to
it later).

llvm-svn: 209004
2014-05-16 18:26:53 +00:00
David Blaikie bc094f387b DebugInfo: Don't put fission type units in comdat sections.
Since type units in the dwo file are handled by a debug aware tool, they
don't need to leverage the ELF comdat grouping to implement
deduplication. Avoid creating all the .group sections for these as a
space optimization.

llvm-svn: 208930
2014-05-15 23:18:15 +00:00
David Blaikie 9ba7254688 DebugInfo: Sure up subprogram variable list handling with more assertions and fewer conditionals.
Many old tests using prior schemas still had some brokenness here (both
indirect arrays and arrays with single bogus elements). Fixed those up
so they don't hit the new assertions.

Also reduced nesting in some places, etc.

llvm-svn: 208817
2014-05-14 21:52:46 +00:00
David Blaikie 7af6e6f267 DebugInfo: Assert that a CU's subprogram list contains only subprograms.
llvm-svn: 208816
2014-05-14 21:52:37 +00:00
David Blaikie 866c87f07b DebugInfo: Simplify/correct test for correct constant emission when dealing with derived types.
This test was using the inliner and other optimizations to test a case
that's actually a bug anyway. Bug and possible fix/discussion described
here ( http://reviews.llvm.org/D3714 ).

But the functionality that was implemented along with this test is still
desired, so simplify the test to verify a more obvious/less wrong case
that the functionality addressed: looking through const sugar to the
underlying type when emitting a constant (so the constant is emitted as
signed/unsigned as appropriate depending on the signedness of the
underlying type).

llvm-svn: 208504
2014-05-11 17:25:50 +00:00
David Blaikie c05c8f483b DwarfUnit: Share common constant value emission between APInts of small (<= 64 bit) and MCOperand immediates.
Doesn't seem a good reason to duplicate this code (it was more literally
duplicated prior to r208494, and while the dataN code /does/ actually
fire in this case, it doesn't seem necessary (and the DWARF standard
recommends using udata/sdata pervasively instead of dataN, so as to
indicate signedness of the values))

llvm-svn: 208495
2014-05-11 15:47:39 +00:00
David Blaikie 899ae61fee Revert "Emit DW_AT_object_pointer once, on the declaration, for each function."
Breaks GDB buildbot
(http://lab.llvm.org:8011/builders/clang-x86_64-ubuntu-gdb-75/builds/14517)

GCC emits DW_AT_object_pointer /everywhere/ (declaration, abstract
definition, inlined subroutine), but it looks like GCC relies on it
being somewhere other than the declaration, at least. I'll experiment
further & can hopefully still remove it from the inlined_subroutine.

This reverts commit r207705.

llvm-svn: 207719
2014-04-30 22:58:19 +00:00
David Blaikie 44078b3260 DebugInfo: Omit DW_AT_artificial on DW_TAG_formal_parameters in DW_TAG_inlined_subroutines.
They just don't need to be there - they're inherited from the abstract
definition. In theory I would like them to be inherited from the
declaration, but the DWARF standard doesn't quite say that... we can
probably do it anyway but I'm less confident about that so I'll leave it
for a separate commit.

llvm-svn: 207717
2014-04-30 22:41:33 +00:00
David Blaikie 3b2a53a437 Emit DW_AT_object_pointer once, on the declaration, for each function.
This effectively reverts r164326, but adds some comments and
justification and ensures we /don't/ emit the DW_AT_object_pointer on
the (abstract and concrete) definitions. (while still preserving it on
standalone definitions involving ObjC Blocks)

This does increase the size of member function declarations from 7 to 11
bytes, unfortunately, but still seems like the Right Thing to do so that
callers that see only the declaration still have the information about
the object pointer. That said, I don't know what, if any, DWARF
consumers don't have a heuristic to guess this in the case of normal
C++ member functions - perhaps we can remove it entirely.

llvm-svn: 207705
2014-04-30 21:29:41 +00:00
David Blaikie d8f0ac7b4a DwarfDebug: Omit DW_AT_object_pointer on inlined_subroutines
While refactoring out constructScopeDIE into two functions I realized we
were emitting DW_AT_object_pointer in the inlined subroutine when we
didn't need to (GCC doesn't, and the abstract subprogram definition has
the information already).

So here's the refactoring and the bug fix. This is one step of
refactoring to remove some subtle memory ownership semantics. It turns
out the original constructScopeDIE returned ownership in its return
value in some cases and not in others. The split into two functions now
separates those two semantics - further cleanup (unique_ptr, etc) will
follow.

llvm-svn: 207441
2014-04-28 20:27:02 +00:00
David Blaikie 2b4669de8a DebugInfo: Fix and test a regression caused by r207263 causing the DW_AT_object_pointer to go missing on blocks
Noticed by inspection. Test coverage added.

llvm-svn: 207333
2014-04-26 22:12:18 +00:00
David Blaikie 9c34526c17 Include C++ source for debug info test case committed in r207323
llvm-svn: 207324
2014-04-26 18:25:07 +00:00