Commit Graph

64 Commits

Author SHA1 Message Date
David Blaikie 2f04011435 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.

This was then reverted again in r213581 as it caused PR20367. The root
cause of this was the early exit in LiveDebugVariables meant that
spurious DBG_VALUE intrinsics that referenced dead variables were not
removed, causing an assertion/crash later on. The fix is to have
LiveDebugVariables strip all DBG_VALUE intrinsics in functions without
debug info as they're not needed anyway. Test case added to cover this
situation (that occurs when a debug-having function is inlined into a
nodebug function) in test/DebugInfo/X86/nodebug_with_debug_loc.ll

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: 213952
2014-07-25 16:10:16 +00:00
David Blaikie 26f2268cc5 Revert "Recommit r212203: Don't try to construct debug LexicalScopes hierarchy for functions that do not have top level debug information."
This reverts commit r212649 while I investigate/reduce/etc PR20367.

llvm-svn: 213581
2014-07-21 20:45:59 +00:00
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
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 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 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
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 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
Adrian Prantl 8714aaf0a5 Re-apply r206096 after investigating the gdb buildbot failure.
Thanks to dblaikie for updating the testcase!

Debug info: (bugfix) C++ C/Dtors can be compiled to multiple functions,
therefore, their declaration cannot have one DW_AT_linkage_name.
The specific instances however can and should have that attribute.

This patch reorders the code in DwarfUnit::getOrCreateSubprogramDIE()
to emit linkage names for C/Dtors.

rdar://problem/16362674.

llvm-svn: 206210
2014-04-14 21:16:04 +00:00
Adrian Prantl d3dd11d628 Revert "Debug info: (bugfix) C++ C/Dtors can be compiled to multiple functions,"
This reverts commit 206096 while I investigate why this broke the gdb
buildbot.

llvm-svn: 206103
2014-04-12 04:25:02 +00:00
Adrian Prantl 1f2f3c3434 Debug info: (bugfix) C++ C/Dtors can be compiled to multiple functions,
therefore, their declaration cannot have one DW_AT_linkage_name.
The specific instances however can and should have that attribute.

This patch reorders the code in DwarfUnit::getOrCreateSubprogramDIE()
to emit linkage names for C/Dtors.

rdar://problem/16362674.

llvm-svn: 206096
2014-04-12 01:44:42 +00:00
David Blaikie f5040a64bb DebugInfo: Refactor test to not rely on fixed DIE offsets
llvm-svn: 203186
2014-03-07 01:19:31 +00:00
David Blaikie 5e390e4df7 DebugInfo: Remove some unneeded conditionals now that DIBuilder no longer emits zero-length arrays as {i32 0}
A bunch of test cases needed to be cleaned up for this, many my fault -
when implementid imported modules I updated test cases by simply
duplicating the prior metadata field - which wasn't always the empty
metadata entry.

llvm-svn: 200731
2014-02-04 01:23:52 +00:00
Eric Christopher cf48ade87e Revert "Use DW_AT_high_pc and DW_AT_low_pc for the high and low pc for a"
in order to fix the cygwin/mingw bots.

This reverts commit r199990.

llvm-svn: 199991
2014-01-24 11:52:53 +00:00
Eric Christopher c528858cbd Use DW_AT_high_pc and DW_AT_low_pc for the high and low pc for a
compile unit. Make these relocations on the platforms that need
relocations and add a routine to ensure that we don't put the
addresses in an offset table for split dwarf.

llvm-svn: 199990
2014-01-24 11:40:29 +00:00
David Blaikie 22b29a5f1a Revert "Reverting r193835 due to weirdness with Go..."
The cgo problem was that it wants dwarf2 which doesn't support direct
constant encoding of the location. So let's add support for dwarf2
encoding (using a location expression) of data member locations.

This reverts commit r198385.

llvm-svn: 198389
2014-01-03 01:30:05 +00:00
David Blaikie 2ada116a34 Reverting r193835 due to weirdness with Go...
Apologies for the noise - we're seeing some Go failures with cgo
interacting with Clang's debug info due to this change.

llvm-svn: 198385
2014-01-03 00:48:38 +00:00
Manman Ren 409558f81e Debug Info: update testing cases to specify the debug info version number.
We are going to drop debug info without a version number or with a different
version number, to make sure we don't crash when we see bitcode files with
different debug info metadata format.

llvm-svn: 195504
2013-11-22 21:49:45 +00:00
David Blaikie 71d34a2eef DebugInfo: Emit member variable locations as data instead of expressions in blocks
Drive by space optimization. Also makes the DIEs more regular which
might speed up DWARF parsing.

llvm-svn: 193835
2013-11-01 00:25:45 +00:00
David Blaikie 309ffe4016 DebugInfo: Fix ordering of members after r191928
In the case (shown in the attached test) where a member function
definition was emitted into debug info the following could occur:

1) build the debug info for the member function definition
2) in (1), build the debug info for the member function declaration
3) construct and add the member function declaration DIE
4) add it to its context
5) build its context (the type it is a member of)
6) construct the members and add them to the type
7) except don't add member functions because "getOrCreateSubprogram"
adds the function to its parent anyway
8) except we're only partway through building this subprogram
declaration so it hasn't been added yet - but we returned the partially
constructed DIE (since it's already in the MDNode->DIE mapping to avoid
infinitely recursing trying to create the member function DIE)
9) once the type is constructed, add the member function to it
10) now the members are out of order (the member function being defined
is listed as the last member, even though it was declared as the first)

To avoid this, construct the context of the subprogram DIE before we
query to see if it exists. That way we never end up creating it before
creating its context and ending up in this situation.

Alternatively, the type construction that visits/builds all the members
could call something like getOrCreateSubprogram, but that doesn't ever
do the "add to context" step. Then the type building code would always
be responsible for adding members (and the subprogram "addToContextDIE"
would no-op because the context building would have added the subprogram
declaration to the type/context DIE already).

(the test cases updated were overly-sensitive to offsets or abbreviation
numbers. We don't have a nice way to make these tests more robust as yet
- multiline FileCheck matches would be required)

llvm-svn: 191939
2013-10-04 01:39:59 +00:00
Manman Ren f2a88f3622 Debug Info Testing: update context from empty string to null.
Context should be either null or MDNode.

llvm-svn: 190267
2013-09-08 03:11:54 +00:00
Manman Ren deeafd8a58 Debug Info Testing: updated to use NULL instead of "i32 0" in a few fields.
Field 2 of DIType (Context), field 9 of DIDerivedType (TypeDerivedFrom),
field 12 of DICompositeType (ContainingType), fields 2, 7, 12 of DISubprogram
(Context, Type, ContainingType).

llvm-svn: 190205
2013-09-06 21:03:58 +00:00
Manman Ren 4c12bf5ac7 Debug Info Testing: Updated to use null instead of "i32 0" for containing-type
field of DICompositeType.

This will help the follow-on patch of using DITypeRef for containing-type field.

llvm-svn: 190187
2013-09-06 18:13:59 +00:00
Manman Ren 0ed70aeb85 Debug Info: add an identifier field to DICompositeType.
DICompositeType will have an identifier field at position 14. For now, the
field is set to null in DIBuilder.
For DICompositeTypes where the template argument field (the 13th field)
was optional, modify DIBuilder to make sure the template argument field is set.
Now DICompositeType has 15 fields.

Update DIBuilder to use NULL instead of "i32 0" for null value of a MDNode.
Update verifier to check that DICompositeType has 15 fields and the last
field is null or a MDString.

Update testing cases to include an extra field for DICompositeType.
The identifier field will be used by type uniquing so a front end can
genearte a DICompositeType with a unique identifer.

llvm-svn: 189282
2013-08-26 22:39:55 +00:00
Eric Christopher f20ff979e9 Revert "Make sure debug info contains linkage names (DW_AT_MIPS_linkage_name)"
temporarily while investigating gdb.cp/templates.exp.

This reverts commit r181471.

llvm-svn: 181496
2013-05-09 00:42:33 +00:00
Eric Christopher 697fa1c8be Make sure debug info contains linkage names (DW_AT_MIPS_linkage_name)
for constructors and destructors since the original declaration given
by the AT_specification both won't and can't.

Patch by Yacine Belkadi, I've cleaned up the testcases.

llvm-svn: 181471
2013-05-08 21:23:22 +00:00
David Blaikie f55abeaf4c Revert "Revert "PR14606: debug info imported_module support""
This reverts commit r179840 with a fix to test/DebugInfo/two-cus-from-same-file.ll

I'm not sure why that test only failed on ARM & MIPS and not X86 Linux, even
though the debug info was clearly invalid on all of them, but this ought to fix
it.

llvm-svn: 179996
2013-04-22 06:12:31 +00:00
Eric Christopher 0e89ade8ff Revert "PR14606: debug info imported_module support"
This reverts commit r179836 as it seems to have caused test failures.

llvm-svn: 179840
2013-04-19 07:47:16 +00:00
David Blaikie 88564f3cf7 PR14606: debug info imported_module support
Adding another CU-wide list, in this case of imported_modules (since they
should be relatively rare, it seemed better to add a list where each element
had a "context" value, rather than add a (usually empty) list to every scope).
This takes care of DW_TAG_imported_module, but to fully address PR14606 we'll
need to expand this to cover DW_TAG_imported_declaration too.

llvm-svn: 179836
2013-04-19 06:57:04 +00:00
David Blaikie 5692e72f30 Revert "Adding DIImportedModules to DIScopes."
This reverts commit 342d92c7a0adeabc9ab00f3f0d88d739fe7da4c7.

Turns out we're going with a different schema design to represent
DW_TAG_imported_modules so we won't need this extra field.

llvm-svn: 178215
2013-03-28 02:44:59 +00:00
David Blaikie a26d70358f Adding DIImportedModules to DIScopes.
This is just the basic groundwork for supporting DW_TAG_imported_module but I
wanted to commit this before pushing support further into Clang or LLVM so that
this rather churny change is isolated from the rest of the work. The major
churn here is obviously adding another field (within the common DIScope prefix)
to all DIScopes (files, classes, namespaces, lexical scopes, etc). This should
be the last big churny change needed for DW_TAG_imported_module/using directive
support/PR14606.

llvm-svn: 178099
2013-03-27 00:07:26 +00:00
David Blaikie f333dc9571 Reorder the DIFile field in DILexicalBlock to become a prefix common with other DIScopes
llvm-svn: 177703
2013-03-22 05:47:44 +00:00
David Blaikie 0d7d62e4b2 Move the DIFile in DISubprogram to the beginning to be a common prefix along with other DIScopes
llvm-svn: 177674
2013-03-21 22:29:36 +00:00
David Blaikie cc8d090163 Remove unused field in DISubprogram
llvm-svn: 177661
2013-03-21 20:28:52 +00:00
David Blaikie efb0d65ed7 Debug info: refactor the first field of DICompileUnit to be a raw file/directory pair
This removes the DICompileUnit special case from DIScope.

llvm-svn: 177610
2013-03-20 23:58:12 +00:00
David Blaikie 3b88852a2d Debug Info: Swap the 2nd and 3rd parameters to DICompileUnit to match the common DIScope prefix
llvm-svn: 177595
2013-03-20 22:52:54 +00:00
David Blaikie 43a729d165 Remove unused field in DICompileUnit
llvm-svn: 177590
2013-03-20 22:34:33 +00:00
David Blaikie 200b6ed80f Refactor the DIFile (2nd) parameter to DITypes to be an MDNode reference to a raw directory/file pair
This makes DIType's first non-tag parameter the same as DIFile's, allowing them
to both share the common implementation of getFilename/getDirectory in DIScope.

llvm-svn: 177467
2013-03-20 00:26:26 +00:00
David Blaikie abec74b38e Move the DIFile operand to DITypes from the 4th operand to the 2nd.
This is another step along the way to making all DIScopes have a common prefix
which can be added to in a general manner to support using directives
(DW_TAG_imported_module).

llvm-svn: 177462
2013-03-19 23:25:22 +00:00
David Blaikie 8fb8224578 Split out filename & directory from DIFile to start generalizing over DIScopes
This is the first step to making all DIScopes have a common metadata prefix (so
that things (using directives, for example) that can appear in any scope can be
added to that common prefix). DIFile is itself a DIScope so the common prefix
of all DIScopes cannot be a DIFile - instead it's the raw filename/directory
name pair.

llvm-svn: 177239
2013-03-17 21:13:55 +00:00
David Blaikie 1ca2f36289 Refactor filename/directory in DICompileUnit into a DIFile
This is the next step towards making the metadata for DIScopes have a common
prefix rather than having to delegate based on their tag type.

llvm-svn: 176913
2013-03-13 00:01:35 +00:00
David Blaikie 452c3ff649 Remove unused "isMain" field from DICompileUnit
llvm-svn: 176910
2013-03-12 22:43:04 +00:00
David Blaikie a4f770d51c Update debug info test cases with empty SplitDebugFilename field.
This could be 'null' or the empty string, DIDescriptor::getStringField
coalesces the two cases anyway so it's just a matter of legible/efficient
representation.

The change in behavior of the DICompileUnit::get* functions could be
subsumed by the full verification check - but ideally that should just be an
assertion if we could front-load the actual debug info metadata failure paths.

llvm-svn: 176907
2013-03-12 22:25:36 +00:00
David Blaikie 47922fb006 Upgrading debug info test cases to be (more) compatible with the current debug info format.
These cases were found by further work to remove support for debug info
versioning. Common cleanups (other than changing the version info in the tag
field) included adding the last parameter to compile_units (recently added for
fission support) and other cases of trailing fields in lexical blocks, compile
units, and subprograms.

llvm-svn: 176834
2013-03-11 22:37:40 +00:00