Summary:
1) Make sure to discard dangling debug info if the variable (or
variable fragment) is mapped to something new before we had a
chance to resolve the dangling debug info.
2) When resolving debug info, make sure to bump the associated
SDNodeOrder to ensure that the DBG_VALUE is emitted after the
instruction that defines the value used in the DBG_VALUE.
This will avoid a debug-use before def scenario as seen in
https://bugs.llvm.org/show_bug.cgi?id=36417.
The new test case, test/DebugInfo/X86/sdag-dangling-dbgvalue.ll,
show some other limitations in how dangling debug info is
handled in the SelectionDAG. Since we currently only support
having one dangling dbg.value per Value, we will end up dropping
debug info when there are more than one variable that is described
by the same "dangling value".
Reviewers: aprantl
Reviewed By: aprantl
Subscribers: aprantl, eraman, llvm-commits, JDevlieghere
Tags: #debug-info
Differential Revision: https://reviews.llvm.org/D44369
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@327303 91177308-0d34-0410-b5e6-96231b3b80d8
Fixes the bug found by asan. Also XFAIL the new test for Darwin,
which is stuck on DWARF v2, and fix up other tests so they stop
failing on Windows.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@326839 91177308-0d34-0410-b5e6-96231b3b80d8
DWARF v5 specifies that the root file (also given in the DW_AT_name
attribute of the compilation unit DIE) should be emitted explicitly to
the line table's list of files. This makes the line table more
independent of the .debug_info section.
Differential Revision: https://reviews.llvm.org/D44054
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@326758 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r326328 to remove checks for emission of certain
sections after discussion with Eric Christofer.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@326436 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Some targets does not support labels inside debug sections, but support
references in form `section +|- offset`. Patch adds initial support
for this. Also, this patch disables emission of all additional debug
sections that may have labels inside of it (like pub sections and
string tables).
Reviewers: probinson, echristo
Subscribers: JDevlieghere, llvm-commits
Differential Revision: https://reviews.llvm.org/D43627
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@326328 91177308-0d34-0410-b5e6-96231b3b80d8
In DWARF v5 the Line Number Program Header is extensible, allowing values with
new content types. In this extension a content type is added,
DW_LNCT_LLVM_source, which contains the embedded source code of the file.
Add new optional attribute for !DIFile IR metadata called source which contains
source text. Use this to output the source to the DWARF line table of code
objects. Analogously extend METADATA_FILE in Bitcode and .file directive in ASM
to support optional source.
Teach llvm-dwarfdump and llvm-objdump about the new values. Update the output
format of llvm-dwarfdump to make room for the new attribute on file_names
entries, and support embedded sources for the -source option in llvm-objdump.
Differential Revision: https://reviews.llvm.org/D42765
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@325970 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
If there is no debug info for macros, do not emit labels for empty
macinfo sections.
Reviewers: probinson, echristo
Subscribers: aprantl, llvm-commits, JDevlieghere
Differential Revision: https://reviews.llvm.org/D43589
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@325803 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This commit separates the abstract accelerator table data structure
from the code for writing out an on-disk representation of a specific
accelerator table format. The idea is that former (now called
AccelTable<T>) can be reused for the DWARF v5 accelerator tables
as-is, without any further customizations.
Some bits of the emission code (now living in the EmissionContext class)
can be reused for DWARF v5 as well, but the subtle differences in the
layout of various subtables mean the sharing is not always possible.
(Also, the individual emit*** functions are fairly simple so there's a
tradeoff between making a bigger general-purpose function, and two
smaller targeted functions.)
Another advantage of this setup is that more of the serialization logic
can be hidden in the .cpp file -- I have moved declarations of the
header and all the emission functions there.
Reviewers: JDevlieghere, aprantl, probinson, dblaikie
Subscribers: echristo, clayborg, vleschuk, llvm-commits
Differential Revision: https://reviews.llvm.org/D43285
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@325516 91177308-0d34-0410-b5e6-96231b3b80d8
The prologue-end line record must be emitted after the last
instruction that is part of the function frame setup code and before
the instruction that marks the beginning of the function body.
Patch by Carlos Alberto Enciso!
Differential Revision: https://reviews.llvm.org/D41762
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@325143 91177308-0d34-0410-b5e6-96231b3b80d8
This patch refactors the way data is stored in the accelerator table and
makes them truly generic. There have been several attempts to do this in
the past:
- D8215 & D8216: Using a union and partial hardcoding.
- D11805: Using inheritance.
- D42246: Using a callback.
In the end I didn't like either of them, because for some reason or
another parts of it felt hacky or decreased runtime performance. I
didn't want to completely rewrite them as I was hoping that we could
reuse parts for the successor in the DWARF standard. However, it seems
less and less likely that there will be a lot of opportunities for
sharing code and/or an interface.
Originally I choose to template the whole class, because it introduces
no performance overhead compared to the original implementation.
We ended up settling on a hybrid between a templated method and a
virtual call to emit the data. The motivation is that we don't want to
increase code size for a feature that should soon be superseded by the
DWARFv5 accelerator tables. While the code will continue to be used for
compatibility, it won't be on the hot path. Furthermore this does not
regress performance compared to Apple's internal implementation that
already uses virtual calls for this.
A quick summary for why these changes are necessary: dsymutil likes to
reuse the current implementation of the Apple accelerator tables.
However, LLDB expects a slightly different interface than what is
currently emitted. Additionally, in dsymutil we only have offsets and no
actual DIEs.
Although the patch suggests a lot of code has changed, this change is
pretty straightforward:
- We created an abstract class `AppleAccelTableData` to serve as an
interface for the different data classes.
- We created two implementations of this class, one for type tables and
one for everything else. There will be a third one for dsymutil that
takes just the offset.
- We use the supplied class to deduct the atoms for the header which
makes the structure of the table fully self contained, although not
enforced by the interface as was the case for the fully templated
approach.
- We renamed the prefix from DWARF- to Apple- to make space for the
future implementation of .debug_names.
This change is NFC and relies on the existing tests.
Differential revision: https://reviews.llvm.org/D42334
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@323653 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: This is the producer side for DWARF v5 string offsets tables. The reader/consumer
side was committed with r321295. All compile and type units in a module share a
contribution to the string offsets table. Indirect strings use the strx{1,2,3,4} index forms.
Reviewers: dblaikie, aprantl, JDevliegehere
Differential Revision: https://reviews.llvm.org/D42021
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@323546 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Currently -glldb turns on emission of apple tables on all targets, but
lldb is only really capable of consuming them on darwin. Furthermore,
making lldb consume these tables is not straight-forward because of the
differences in how the debug info is distributed on darwin vs. elf
targets.
The darwin debug model assumes that the debug info (along with
accelerator tables) will either remain in the .o files or it will be
linked into a dsym bundle by a linker that knows how to merge these
tables. In the elf world, all present linkers will simply concatenate
these accelerator tables into the shared object. Since the tables are
not self-terminating, this renders the tables unusable, as the debugger
cannot pry the individual tables apart anymore.
It might theoretically be possible to make the tables work with split
dwarf, as that is somewhat similar to the apple .o model, but
unfortunately right now the combination of -glldb and -gsplit-dwarf
produces broken object files.
Until these issues are resolved there is no point in emitting the apple
tables for these targets. At best, it wastes space; at worst, it breaks
compilation and prevents the user from getting other benefits of -glldb.
Reviewers: probinson, aprantl, dblaikie
Subscribers: emaste, dim, llvm-commits, JDevlieghere
Differential Revision: https://reviews.llvm.org/D41986
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@322633 91177308-0d34-0410-b5e6-96231b3b80d8
Pass MD5 checksums through from IR to assembly/object files.
After this, getting Clang to compute the MD5 should be the last step
to supporting MD5 in the DWARF v5 line table header.
Differential Revision: https://reviews.llvm.org/D41926
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@322391 91177308-0d34-0410-b5e6-96231b3b80d8
Extend .file directive syntax to allow specifying an MD5 checksum for
the source file. Emit the checksums in DWARF v5 line tables.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@322134 91177308-0d34-0410-b5e6-96231b3b80d8
All these headers already depend on CodeGen headers so moving them into
CodeGen fixes the layering (since CodeGen depends on Target, not the
other way around).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@318490 91177308-0d34-0410-b5e6-96231b3b80d8
The comparator passed to std::sort must provide a strict weak ordering;
otherwise, the behavior is undefined.
Fixes an assertion failure generating debug info for globals
split by GlobalOpt. I have a testcase, but not sure how to reduce it,
so not included here. (Someone else came up with a testcase, but I
can't reproduce the crash with it, presumably because my version of LLVM
ends up sorting the array differently.)
This isn't really a complete fix (see the FIXME in the patch), but at
least it doesn't have undefined behavior.
Differential Revision: https://reviews.llvm.org/D38830
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@315619 91177308-0d34-0410-b5e6-96231b3b80d8
While this shouldn't be necessary anymore, we have cases where we run
into the assertion below, i.e. cases with two non-fragment entries for the
same variable at different frame indices.
This should be fixed, but for now, we should revert to a version that
does not trigger asserts.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@315576 91177308-0d34-0410-b5e6-96231b3b80d8
Since r315388 we have a shorter way to say this, so we'll replace
MI->getParent()->getParent() with MI->getMF() in a few places.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@315390 91177308-0d34-0410-b5e6-96231b3b80d8
Some passes might duplicate calls to llvm.dbg.declare creating
duplicate frame index expression which currently trigger an assertion
which is meant to catch erroneous, overlapping fragment declarations.
But identical frame index expressions are just redundant and don't
actually conflict with each other, so we can be more lenient and just
ignore the duplicates.
Reviewers: aprantl, rnk
Subscribers: llvm-commits, JDevlieghere
Differential Revision: https://reviews.llvm.org/D38540
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@315279 91177308-0d34-0410-b5e6-96231b3b80d8
A prologue-end line record is emitted with an incorrect associated address,
which causes a debugger to show the beginning of function body to be inside
the prologue.
Patch written by Carlos Alberto Enciso.
Differential Revision: https://reviews.llvm.org/D37625
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@313047 91177308-0d34-0410-b5e6-96231b3b80d8
Chromium's gold build seems to have trouble with this (gold produces
errors) - not sure if it's gold that's not coping with the valid
representation, or a bug in the implementation in LLVM, etc.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@309630 91177308-0d34-0410-b5e6-96231b3b80d8
Missed the resetting base address selections when going from a base
address version to zero base address for non-base-addressed entries.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@309529 91177308-0d34-0410-b5e6-96231b3b80d8
(from comments in the test)
Group ranges in a range list that apply to the same section and use a base
address selection entry to reduce the number of relocations to one reloc per
section per range list. DWARF5 debug_rnglist will be more efficient than this
in terms of relocations, but it's still better than one reloc per entry in a
range list.
This is an object/executable size tradeoff - shrinking objects, but growing
the linked executable. In one large binary tested, total object size (not just
debug info) shrank by 16%, entirely relocation entries. Linked executable
grew by 4%. This was with compressed debug info in the objects, uncompressed
in the linked executable. Without compression in the objects, the win would be
smaller (the growth of debug_ranges itself would be more significant).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@309526 91177308-0d34-0410-b5e6-96231b3b80d8
This can come up in ThinLTO & wastes space & makes degenerate IR.
As per the added FIXME, ultimately, local imported entities should hang
off the function and that way the imported entity list on the CU can be
tested for emptiness like all the other CU lists.
(function-attached local imported entities are probably also the best
path forward for fixing how imported entities are handled both in
cross-module use (currently, while ThinLTO preserves the imported
entities, they would not get used at the imported inlined location -
only in the abstract origin that appears in the partial CU created by
the import (which isn't emitted under Fission due to cross-CU
limitations there)) and to reduce the number of points where imported
entities are emitted (they're currently emitted into every inlined
instance, concrete instance, and abstract origin - they should only go
in teh abstract origin if there is one, otherwise in the concrete
instance - but this requires lots of delayed handling and wiring up,
same as abstract variables & subprograms))
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@309354 91177308-0d34-0410-b5e6-96231b3b80d8
Local imported entities at the top level of a subprogram were being
handled differently from those in nested scopes - that different
handling would cause pseudo concrete out-of-line definitions to be
created (but without any of their attributes, nor an abstract_origin) in
the case where there was no real concrete definition.
These local imported entities also only appeared in the concrete
definition where those imported entities in nested scopes appear in all
cases (abstract, concrete, and inlined). This change at least makes top
level case handle the same as the others - though there's a FIXME to
improve this to /only/ emit them into the abstract origin (though this
requires more plumbing - like the abstract subprogram and variable
handling that must defer population until the end of the unit to
discover if there is an abstract origin, or only a standalone concrete
definition).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@309237 91177308-0d34-0410-b5e6-96231b3b80d8
This is a better fix than r308708 for the problem introduced in
r304020. It restores the skeleton CU testcases modified by that commit
to their original form and most importantly ensures that
frontend-generated skeleton CUs (such as used to point to Clang
modules) come after the regular CUs. This broke for DICompileUnit
nodes that don't have any immediate children because they are now
constructed lazily instead of the order in which they are listed in
!llvm.dbg.cu. After this commit we still don't guarantee that order,
but we do guarantee that empty skeletons come last.
Shipping versions of LLDB are very sensitive to the ordering of
CUs. I'll track a fix for LLDB to be more permissive separately.
This fixes a test failure in the LLDB testsuite.
rdar://problem/33357252
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@309154 91177308-0d34-0410-b5e6-96231b3b80d8
The instruction it falls over on is an IMPLICT_DEF that also happens
to be the only instruction in its lexical scope. That LexicalScope has
never been created because its range is empty. This patch skips over
all meta-instructions instead of just DBG_VALUEs.
Thanks to David Blaikie for providing a testcase!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305853 91177308-0d34-0410-b5e6-96231b3b80d8
For the following motivating example
bool c();
void f();
bool start() {
bool result = c();
if (!c()) {
result = false;
goto exit;
}
f();
result = true;
exit:
return result;
}
we would previously generate a single DW_AT_const_value(1) because
only the DBG_VALUE in the second-to-last basic block survived
codegen. This patch improves the heuristic used to determine when a
DBG_VALUE is available at the beginning of its variable's enclosing
lexical scope:
- Stop giving singular constants blanket permission to take over the
entire scope. There is still a special case for constants in the
function prologue that we also miight want to retire later.
- Use the lexical scope information to determine available-at-entry
instead of proximity to the function prologue.
After this patch we generate a location list with a more accurate
narrower availability for the constant true value. As a pleasant side
effect, we also generate inline locations instead of location lists
where a loacation covers the entire range of the enclosing lexical
scope.
Measured on compiling llc with four targets this doesn't have an
effect on compile time and reduces the size of the debug info for llc
by ~600K.
rdar://problem/30286912
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305599 91177308-0d34-0410-b5e6-96231b3b80d8
