Commit Graph

1957 Commits

Author SHA1 Message Date
Paul Robinson b271f31d8d Reapply "[DWARFv5] Emit file 0 to the line table."
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.
We emit the new syntax only for DWARF v5 and later.

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.  Last but not least, don't break "clang -g" of an assembler
file that has .file directives in it.

Differential Revision: https://reviews.llvm.org/D44054

llvm-svn: 328805
2018-03-29 17:16:41 +00:00
Alexander Potapenko 202f809437 Revert "Reapply "[DWARFv5] Emit file 0 to the line table.""
This reverts commit r328676.

Commit r328676 broke the -no-integrated-as flag necessary to build Linux kernel with Clang:

$ cat t.c
void foo() {}
$ clang -no-integrated-as   -c  t.c -g
/tmp/t-dcdec5.s: Assembler messages:
/tmp/t-dcdec5.s:8: Error: file number less than one
clang-7.0: error: assembler command failed with exit code 1 (use -v to see invocation)

llvm-svn: 328699
2018-03-28 12:36:46 +00:00
Paul Robinson 07480bd177 Reapply "[DWARFv5] Emit file 0 to the line table."
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.

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.  Last but not least, don't break "clang -g" of an assembler
file that has .file directives in it.

Differential Revision: https://reviews.llvm.org/D44054

llvm-svn: 328676
2018-03-27 22:40:34 +00:00
Paul Robinson 7cb26ad2ef [DWARF] Suppress split line tables more carefully.
If a given split type unit does not have source locations, don't have
it refer to the split line table.
If no split type unit refers to the split line table, don't emit the
line table at all.

This will save a little space on rare occasions, but also refactors
things a bit to improve which class is responsible for what.

Responding to review comments on r326395.

Differential Revision: https://reviews.llvm.org/D44220

llvm-svn: 328670
2018-03-27 21:28:59 +00:00
David Blaikie 6054e650ff Move TargetLoweringObjectFile from CodeGen to Target to fix layering
It's implemented in Target & include from other Target headers, so the
header should be in Target.

llvm-svn: 328392
2018-03-23 23:58:19 +00:00
Alexey Bataev bff360865b [DEBUGINFO] Add flag for DWARF2 to use sections as references.
Summary:
Some targets does not support labels inside debug sections, but support
references in form `section+offset`. Patch adds initial support
for this.

Reviewers: echristo, probinson, jlebar

Subscribers: llvm-commits, JDevlieghere

Differential Revision: https://reviews.llvm.org/D43943

llvm-svn: 328314
2018-03-23 13:35:54 +00:00
Alexey Bataev 858a7dd6d7 [DEBUGINFO] Add -no-dwarf-debug-ranges option.
Summary:
Added option -no-dwarf-debug-ranges option to disable emission of
.debug_ranges section.

Reviewers: probinson, echristo

Subscribers: aprantl, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D44384

llvm-svn: 328030
2018-03-20 20:21:38 +00:00
Alexey Bataev 648ed2dedb [DEBUGINFO] Add flag -no-dwarf-pub-sections to disable pub sections.
Summary:
Added a flag -no-dwarf-pub-sections, which allows to disable
emission of DWARF public sections.

Reviewers: probinson, echristo

Subscribers: aprantl, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D44385

llvm-svn: 327994
2018-03-20 16:04:40 +00:00
Bjorn Pettersson a223f815dd [SelectionDAG] Improve handling of dangling debug info
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

llvm-svn: 327303
2018-03-12 18:02:39 +00:00
Alexander Kornienko e12a48bcc0 Revert "Reapply "[DWARFv5] Emit file 0 to the line table.""
This reverts commit r326839.

r326839 breaks assembly file parsing:

$ cat q.c
void g() {}
$ clang -S q.c -g
$ clang -g -c q.s
q.s:9:2: error: file number already allocated
     .file   1 "/tmp/test" "q.c"
     ^

llvm-svn: 326902
2018-03-07 16:27:44 +00:00
Paul Robinson 4428e90efa Reapply "[DWARFv5] Emit file 0 to the line table."
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.

llvm-svn: 326839
2018-03-06 22:37:45 +00:00
Paul Robinson 732e443bb9 Revert "[DWARFv5] Emit file 0 to the line table."
Caused an asan failure.

This reverts commit d54883f081186cdcce74e6f98cfc0438579ec019.
aka r326758

llvm-svn: 326762
2018-03-06 03:15:21 +00:00
Paul Robinson d5069ba3da [DWARFv5] Emit file 0 to the line table.
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

llvm-svn: 326758
2018-03-06 01:59:56 +00:00
Alexey Bataev d7c6fdbcd5 Revert "[DEBUGINFO] Add flag for DWARF2 or less to use sections as references."
This reverts commit r326328 to remove checks for emission of certain
sections after discussion with Eric Christofer.

llvm-svn: 326436
2018-03-01 14:32:37 +00:00
Paul Robinson 1e0116c91d [DWARF] Emit a split line table only if there are split type units.
A .debug_info.dwo section doesn't use the .debug_line.dwo section.

llvm-svn: 326395
2018-03-01 00:12:35 +00:00
Alexey Bataev 9de940b93b [DEBUGINFO] Add flag for DWARF2 or less to use sections as references.
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

llvm-svn: 326328
2018-02-28 15:02:59 +00:00
Mandeep Singh Grang 46d02dee65 [DebugInfo] Stable sort symbols to remove non-deterministic ordering
Summary: This fixes failure in DebugInfo/X86/multiple-aranges.ll uncovered by D39245.

Reviewers: rafael, echristo, probinson

Reviewed By: probinson

Subscribers: probinson, llvm-commits, JDevlieghere

Tags: #debug-info

Differential Revision: https://reviews.llvm.org/D39950

llvm-svn: 326056
2018-02-25 19:52:34 +00:00
Scott Linder 16c7bdaf32 [DebugInfo] Support DWARF v5 source code embedding extension
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

llvm-svn: 325970
2018-02-23 23:01:06 +00:00
Alexey Bataev bd786944b9 [DEBUGINFO] Do not output labels for empty macinfo sections.
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

llvm-svn: 325803
2018-02-22 16:20:30 +00:00
Alexey Bataev 0d6aeadc40 [DEBUGINFO] Add support for emission of the inlined strings.
Summary:
Patch adds an option for emission of inlined strings rather than
.debug_str section.

Reviewers: echristo, jlebar

Subscribers: eraman, llvm-commits, JDevlieghere

Differential Revision: https://reviews.llvm.org/D43390

llvm-svn: 325583
2018-02-20 15:28:08 +00:00
Pavel Labath a7c457d288 [CodeGen] Refactor AppleAccelTable
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

llvm-svn: 325516
2018-02-19 16:12:20 +00:00
Paul Robinson ee88ed6753 [DWARF] Fix incorrect prologue end line record.
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

llvm-svn: 325143
2018-02-14 17:35:52 +00:00
Jonas Devlieghere 855fc3bbca [NFC] Rename DwarfAccelTable and move header.
This patch renames DwarfAccelTable.{h,cpp} to AccelTable.{h,cpp} and
moves the header to the include dir so it is accessible by the
dsymutil implementation.

Differential revision: https://reviews.llvm.org/D42529

llvm-svn: 323654
2018-01-29 14:52:41 +00:00
Jonas Devlieghere e699dfaa7a [NFC] Refactor Apple Accelerator Tables
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

llvm-svn: 323653
2018-01-29 14:52:34 +00:00
Wolfgang Pieb 456b555ffe [DWARF] Generate DWARF v5 string offsets tables along with strx* index forms.
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

llvm-svn: 323546
2018-01-26 18:52:58 +00:00
Pavel Labath 67530e478b Don't emit apple accelerator tables on non-darwin targets
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

llvm-svn: 322633
2018-01-17 11:52:13 +00:00
Paul Robinson 612e89d74f [DWARFv5] CodeGen support for MD5 file checksums
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

llvm-svn: 322391
2018-01-12 19:17:50 +00:00
Paul Robinson 29f5f987f1 [DWARFv5] MC support for MD5 file checksums
Extend .file directive syntax to allow specifying an MD5 checksum for
the source file.  Emit the checksums in DWARF v5 line tables.

llvm-svn: 322134
2018-01-09 23:31:48 +00:00
Matthias Braun f1caa2833f MachineFunction: Return reference from getFunction(); NFC
The Function can never be nullptr so we can return a reference.

llvm-svn: 320884
2017-12-15 22:22:58 +00:00
David Blaikie b3bde2ea50 Fix a bunch more layering of CodeGen headers that are in Target
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).

llvm-svn: 318490
2017-11-17 01:07:10 +00:00
Eli Friedman 48e7549691 [DWARF] Fix bad comparator in sortGlobalExprs.
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

llvm-svn: 315619
2017-10-12 20:54:08 +00:00
Daniel Jasper 4d93120273 Reinstantiate old/bad deduplication logic that was removed in r315279.
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.

llvm-svn: 315576
2017-10-12 13:25:05 +00:00
Justin Bogner fdf9bf4f16 CodeGen: Minor cleanups to use MachineInstr::getMF. NFC
Since r315388 we have a shorter way to say this, so we'll replace
MI->getParent()->getParent() with MI->getMF() in a few places.

llvm-svn: 315390
2017-10-10 23:50:49 +00:00
Bjorn Steinbrink d36bbe9c89 Ignore all duplicate frame index expression
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

llvm-svn: 315279
2017-10-10 07:46:17 +00:00
Peter Collingbourne b52e23669c IR: Represent -ggnu-pubnames with a flag on the DICompileUnit.
This allows the flag to be persisted through to LTO.

Differential Revision: https://reviews.llvm.org/D37655

llvm-svn: 313078
2017-09-12 21:50:41 +00:00
Robert Lougher 51529eb0c2 Revert "[DWARF] Incorrect prologue end line record."
This reverts commit r313047 as it is causing buildbot failure (lldb inline
stepping tests).

llvm-svn: 313057
2017-09-12 18:23:15 +00:00
Robert Lougher f696a22d3c [DWARF] Incorrect prologue end line record.
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

llvm-svn: 313047
2017-09-12 16:35:25 +00:00
Paul Robinson bb92137080 [DWARF] Line 0 should not have a discriminator.
It's meaningless and takes up extra space in the line table.

Differential Revision: https://reviews.llvm.org/D37364

llvm-svn: 312751
2017-09-07 22:15:44 +00:00
NAKAMURA Takumi a1e97a77f5 Untabify.
llvm-svn: 311875
2017-08-28 06:47:47 +00:00
Adrian Prantl 2116dd360a Filter out non-constant DIGlobalVariableExpressions reachable via the CU
They won't affect the DWARF output, but they will mess with the
sorting of the fragments. This fixes the crash reported in PR34159.

https://bugs.llvm.org/show_bug.cgi?id=34159

llvm-svn: 311217
2017-08-19 01:15:06 +00:00
Eugene Zelenko 6e07bfd0d9 [CodeGen] Fix some Clang-tidy modernize and Include What You Use warnings; other minor fixes (NFC).
llvm-svn: 311124
2017-08-17 21:26:39 +00:00
Adrian Prantl bd6d291c59 Assert that the offset of a DBG_VALUE is always 0. (NFC)
llvm-svn: 309834
2017-08-02 17:19:13 +00:00
Adrian Prantl 5577363a2c Remove the unused Offset field from MachineLocation (NFC)
rdar://problem/33580047

llvm-svn: 309831
2017-08-02 17:07:38 +00:00
Adrian Prantl 2049c0d734 Remove unreachable code. (NFC)
MachineLocation::getOffset() always returns 0.

rdar://problem/33580047

llvm-svn: 309823
2017-08-02 15:22:17 +00:00
David Blaikie c2be863681 DebugInfo: Update flag description that'd been copypasted from another
Post-commit review feedback from Paul Robinson on r309630. Thanks Paul!

llvm-svn: 309685
2017-08-01 14:50:50 +00:00
David Blaikie 038e28a5a7 DebugInfo: Put range base specifier entry functionality behind a flag
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.

llvm-svn: 309630
2017-07-31 21:48:42 +00:00
David Blaikie 4dd663752d DebugInfo: Fix r309526, ensure resetting base address selection entries are used
Missed the resetting base address selections when going from a base
address version to zero base address for non-base-addressed entries.

llvm-svn: 309529
2017-07-31 00:18:24 +00:00
David Blaikie 89c81a0b91 DebugInfo: Use base address selection entries in debug_ranges to reduce relocations
(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).

llvm-svn: 309526
2017-07-30 22:10:00 +00:00
David Blaikie 89daf77a11 DebugInfo: Consider a CU containing only local imported entities to be 'empty'
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))

llvm-svn: 309354
2017-07-28 03:06:25 +00:00
Adrian Prantl 960e7663f3 remove redundant check
llvm-svn: 309280
2017-07-27 15:24:20 +00:00
David Blaikie 2195e13676 DebugInfo: Ensure imported entities at the top level of an inlined function don't cause degenerate concrete definitions
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).

llvm-svn: 309237
2017-07-27 00:06:53 +00:00
Adrian Prantl 833ad37c90 Do a better job at emitting prefrabricated skeleton CUs.
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

llvm-svn: 309154
2017-07-26 18:48:32 +00:00
Adrian Prantl be66271f04 Debug Info: Support fragmented variables in the MMI side table
This reapplies commit r309034 with a bugfix+test for inlined variables.

llvm-svn: 309057
2017-07-25 23:32:59 +00:00
Adrian Prantl b6d5faf2ea Revert "Debug Info: Support fragmented variables in the MMI side table"
This reverts commit r309034 because of a sanitizer issue.

llvm-svn: 309035
2017-07-25 21:50:45 +00:00
Adrian Prantl 3d1ab0cd1e Debug Info: Support fragmented variables in the MMI side table
<rdar://problem/17816343>

llvm-svn: 309034
2017-07-25 21:29:22 +00:00
Adrian Prantl 65e7ca995d Debug Info: Don't strip clang module skeleton CUs.
This corrects a (hopefully :-) accidental side-effect of r304020.

rdar://problem/33442618

llvm-svn: 308708
2017-07-21 01:24:05 +00:00
Adrian Prantl 25422dcccb Fix a crash in DwarfDebug::validThroughout.
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!

llvm-svn: 305853
2017-06-20 21:08:52 +00:00
Adrian Prantl 274bcbc139 Improve the accuracy of variable ranges .debug_loc location lists.
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

llvm-svn: 305599
2017-06-16 22:40:04 +00:00
Florian Hahn ffc498dfcc Align definition of DW_OP_plus with DWARF spec [3/3]
Summary:
This patch is part of 3 patches that together form a single patch, but must be introduced in stages in order not to break things.
 
The way that LLVM interprets DW_OP_plus in DIExpression nodes is basically that of the DW_OP_plus_uconst operator since LLVM expects an unsigned constant operand. This unnecessarily restricts the DW_OP_plus operator, preventing it from being used to describe the evaluation of runtime values on the expression stack. These patches try to align the semantics of DW_OP_plus and DW_OP_minus with that of the DWARF definition, which pops two elements off the expression stack, performs the operation and pushes the result back on the stack.
 
This is done in three stages:
• The first patch (LLVM) adds support for DW_OP_plus_uconst.
• The second patch (Clang) contains changes all its uses from DW_OP_plus to DW_OP_plus_uconst.
• The third patch (LLVM) changes the semantics of DW_OP_plus and DW_OP_minus to be in line with its DWARF meaning. This patch includes the bitcode upgrade from legacy DIExpressions.

Patch by Sander de Smalen.

Reviewers: echristo, pcc, aprantl

Reviewed By: aprantl

Subscribers: fhahn, javed.absar, aprantl, llvm-commits

Differential Revision: https://reviews.llvm.org/D33894

llvm-svn: 305386
2017-06-14 13:14:38 +00:00
Zachary Turner 264b5d9e88 Move Object format code to lib/BinaryFormat.
This creates a new library called BinaryFormat that has all of
the headers from llvm/Support containing structure and layout
definitions for various types of binary formats like dwarf, coff,
elf, etc as well as the code for identifying a file from its
magic.

Differential Revision: https://reviews.llvm.org/D33843

llvm-svn: 304864
2017-06-07 03:48:56 +00:00
Mehdi Amini 96ab48f9da DebugInfo: Include .dwo file name when hashing multiple CUs in a single file
This is really a workaround for ThinLTO in particular - since it can
import partial CUs that may end up looking very similar/the same as
the same partial import in another ThinLTO compile.

An alternative fix would be to change the DICompileUnit metadata to
include a "primary file" or the like - and when importing for ThinLTO
set the primary file to the name of the DICompileUnit that is being
imported into. This involves changing the schema and would reduce the
excessive uniqueness in the hash that this change creates - allowing
diagnosing of more duplicate CUs than will be caught with this change.

But duplicate CUs can still be caught in non-ThinLTO builds & are mostly
a nuisance rather than a particularly deliberate/effective tool for
finding broken code. (arguably the hash could always include the dwo
file and nothing in fission would break, I think..)

Reapply of r304119 after adding a triple to the test and moving it
to the X86 directory.

llvm-svn: 304130
2017-05-29 06:32:34 +00:00
Mehdi Amini 4181205563 DebugInfo: Omit an empty CU when a subprogram was moved into its use
When the only use of a CU is for a subprogram that's only emitted into
the using CU (to avoid cross-CU references in DWO files), avoid creating
that CU at all.

Reapply of r304111 after adding a triple to the test and moving it
to the X86 directory.

llvm-svn: 304129
2017-05-29 06:25:30 +00:00
Mehdi Amini e161ced16a Revert "DebugInfo: Omit an empty CU when a subprogram was moved into its use"
This reverts commit r304111.
GreenDragon is broken.

llvm-svn: 304126
2017-05-29 05:17:57 +00:00
Mehdi Amini d8056bb7d8 Revert "DebugInfo: Include .dwo file name when hashing multiple CUs in a single file"
This reverts commit r304119 and r304118. GreenDragon is broken.

llvm-svn: 304125
2017-05-29 05:17:54 +00:00
David Blaikie ce0c205813 DebugInfo: Include .dwo file name when hashing multiple CUs in a single file
This is really a workaround for ThinLTO in particular - since it can
import partial CUs that may end up looking very similar/the same as
the same partial import in another ThinLTO compile.

An alternative fix would be to change the DICompileUnit metadata to
include a "primary file" or the like - and when importing for ThinLTO
set the primary file to the name of the DICompileUnit that is being
imported into. This involves changing the schema and would reduce the
excessive uniqueness in the hash that this change creates - allowing
diagnosing of more duplicate CUs than will be caught with this change.

But duplicate CUs can still be caught in non-ThinLTO builds & are mostly
a nuisance rather than a particularly deliberate/effective tool for
finding broken code. (arguably the hash could always include the dwo
file and nothing in fission would break, I think..)

llvm-svn: 304119
2017-05-29 00:48:45 +00:00
David Blaikie f2f898a044 DebugInfo: Omit an empty CU when a subprogram was moved into its use
When the only use of a CU is for a subprogram that's only emitted into
the using CU (to avoid cross-CU references in DWO files), avoid creating
that CU at all.

llvm-svn: 304111
2017-05-28 22:51:37 +00:00
David Blaikie 07963bd1d1 DebugInfo: Do not emit empty CUs
Consistent with GCC and addresses a shortcoming with ThinLTO where many
imported CUs may end up being empty (because the functions imported from
them either ended up not being used (and were then discarded, since
they're imported as available_externally) or optimized away entirely).

Test cases previously testing empty CUs (either intentionally, or
because they didn't need anything more complicated) had a trivial 'int'
or similar basic type added to their retained types list.

This is a first order approximation - a deeper implementation could do
things like:

1) Be more lazy about construction of the CU - for example if two CUs
containing a single identical retained type are linked together, with
this change one of the two CUs will be produced but empty (since a
duplicate type won't be produced).

2) Go further and invert all the CU links the same way the subprogram
link is inverted - keep named CU lists of retained types, macros, etc,
and have those link back to the CU. Then if they're emitted, the CU is
emitted, but never otherwise - this would allow the metadata itself to
be dropped earlier too, though it seems unlikely that's an important
optimization as there shouldn't be many CUs relative to the number of
other entities.

llvm-svn: 304020
2017-05-26 18:52:56 +00:00
David Blaikie 7f2b717b52 DebugInfo: Don't include locations for debug-having code inlined into nodebug functions
This produced 'strange' DWARF anyway - the CU would have no ranges (or
at least not a range including the inlined code) nor any subprogram or
inlined_subroutine - yet the line table would have entries for these
instructions.

(this actually becomes more relevant with changes coming after this,
where a CU without any contents will be omitted entirely - so there
would be no line table to put this on anyway)

llvm-svn: 304004
2017-05-26 17:05:15 +00:00
David Blaikie 2c78f183fe DebugInfo: Simplify scopes+subprogram handling since the subprogram<>cu link inversion
Previously this code was defensive to the situation in which the debug
info scopes would lead to a different subprogram from the subprogram in
the CU's subprogram list (this could've happened with linkonce
functions, etc as per the comment being removed). Since the CU<>SP link
reversal this is no longer possible.

llvm-svn: 303933
2017-05-25 23:11:28 +00:00
David Blaikie b3cee2fb42 DebugInfo: Produce debug_{gnu_}pub{names,types} entries when explicitly requested, even in -gmlt or when empty
Turns out gold doesn't use the DW_AT_GNU_pubnames to decide whether to
parse the rest of the DIEs when building gdb-index. This causes gold to
trip over LLVM's output when there are DW_FORM_ref_addr present.

Gold does use the presence of a debug_gnu_pub{names,types} entry for the
CU to skip parsing the debug_info portion, so make sure that's included
even when empty (technically, when empty there couldn't be any ref_addr
anyway - it only came up when gmlt didn't produce any (even non-empty)
pubnames - but given what that reveals about gold's implementation, this
seems like a good thing to do for consistency).

llvm-svn: 303894
2017-05-25 18:50:28 +00:00
Adrian Prantl fb31da1306 Don't generate line&scope debug info for meta-instructions.
MachineInstructions that don't generate any code (such as
IMPLICIT_DEFs) should not generate any debug info either.

Fixes PR33107.

https://bugs.llvm.org/show_bug.cgi?id=33107

This reapplies r303566 without any modifications. The stage2 build
failures persisted even after reverting this patch, and looking back
through history, it looks like these tests are flaky.

llvm-svn: 303575
2017-05-22 20:47:09 +00:00
Adrian Prantl 334a130a6f Revert "Don't generate line&scope debug info for meta-instructions."
This reverts commit r303566 while investigating a stage2 buildbot failure.

llvm-svn: 303570
2017-05-22 18:50:12 +00:00
Adrian Prantl 4c047f8931 Don't generate line&scope debug info for meta-instructions.
MachineInstructions that don't generate any code (such as
IMPLICIT_DEFs) should not generate any debug info either.

Fixes PR33107.

https://bugs.llvm.org/show_bug.cgi?id=33107

llvm-svn: 303566
2017-05-22 16:21:02 +00:00
David Blaikie 488393f822 DWARF: Avoid cross-CU references under Fission
Turns out that the Fission/Split DWARF package format (DWP) is currently
insufficient to handle cross-CU (ref_addr) references. So for now,
duplicate any debug info needed in these situations:
* inlined_subroutine's abstract_origin
* inlined variable's abstract_origin
* types

Keep the ref_addr behavior in general, including in the split DWARF
inline debug info that can be emitted into the object files for online
symbolication.
Keep a flag to use the old (ref_addr) behavior for testing ways of
addressing this limitation in the DWP tool (& for those not using DWP
packaging).

llvm-svn: 302858
2017-05-12 01:13:45 +00:00
David Blaikie 96b1ed50e8 Move Split DWARF handling to an MC option/command line argument rather than using metadata
Since Split DWARF needs to name the actual .dwo file that is generated,
it can't be known at the time the llvm::Module is produced as it may be
merged with other Modules before the object is generated and that object
may be generated with any name.

By passing the Split DWARF file name when LLVM is producing object code
the .dwo file name in the object file can match correctly.

The support for Split DWARF for implicit modules remains the same -
using metadata to store the dwo name and dwo id so that potentially
multiple skeleton CUs referring to different dwo files can be generated
from one llvm::Module.

llvm-svn: 301062
2017-04-21 23:35:26 +00:00
Adrian Prantl c12cee3600 Fix bug that caused DwarfExpression to drop DW_OP_deref from FI locations
- introduced in r300522 and found via the Swift LLDB testsuite.

The fix is to set the location kind to memory whenever an FrameIndex
location is emitted.

rdar://problem/31707602

llvm-svn: 300793
2017-04-19 23:42:25 +00:00
Adrian Prantl 295c952b67 Revert "Fix bug that caused DwarfExpression to drop DW_OP_deref from FI locations"
This reverts commit r300790.

llvm-svn: 300792
2017-04-19 23:42:17 +00:00
Adrian Prantl 78ff122709 Fix bug that caused DwarfExpression to drop DW_OP_deref from FI locations
- introduced in r300522 and found via the Swift LLDB testsuite.

The fix is to set the location kind to memory whenever an FrameIndex
location is emitted.

rdar://problem/31707602

llvm-svn: 300790
2017-04-19 23:34:14 +00:00
Adrian Prantl 6825fb64e9 PR32382: Fix emitting complex DWARF expressions.
The DWARF specification knows 3 kinds of non-empty simple location
descriptions:
1. Register location descriptions
  - describe a variable in a register
  - consist of only a DW_OP_reg
2. Memory location descriptions
  - describe the address of a variable
3. Implicit location descriptions
  - describe the value of a variable
  - end with DW_OP_stack_value & friends

The existing DwarfExpression code is pretty much ignorant of these
restrictions. This used to not matter because we only emitted very
short expressions that we happened to get right by accident.  This
patch makes DwarfExpression aware of the rules defined by the DWARF
standard and now chooses the right kind of location description for
each expression being emitted.

This would have been an NFC commit (for the existing testsuite) if not
for the way that clang describes captured block variables. Based on
how the previous code in LLVM emitted locations, DW_OP_deref
operations that should have come at the end of the expression are put
at its beginning. Fixing this means changing the semantics of
DIExpression, so this patch bumps the version number of DIExpression
and implements a bitcode upgrade.

There are two major changes in this patch:

I had to fix the semantics of dbg.declare for describing function
arguments. After this patch a dbg.declare always takes the *address*
of a variable as the first argument, even if the argument is not an
alloca.

When lowering a DBG_VALUE, the decision of whether to emit a register
location description or a memory location description depends on the
MachineLocation — register machine locations may get promoted to
memory locations based on their DIExpression. (Future) optimization
passes that want to salvage implicit debug location for variables may
do so by appending a DW_OP_stack_value. For example:
  DBG_VALUE, [RBP-8]                        --> DW_OP_fbreg -8
  DBG_VALUE, RAX                            --> DW_OP_reg0 +0
  DBG_VALUE, RAX, DIExpression(DW_OP_deref) --> DW_OP_reg0 +0

All testcases that were modified were regenerated from clang. I also
added source-based testcases for each of these to the debuginfo-tests
repository over the last week to make sure that no synchronized bugs
slip in. The debuginfo-tests compile from source and run the debugger.

https://bugs.llvm.org/show_bug.cgi?id=32382
<rdar://problem/31205000>

Differential Revision: https://reviews.llvm.org/D31439

llvm-svn: 300522
2017-04-18 01:21:53 +00:00
Konstantin Zhuravlyov dc77b2e960 Distinguish between code pointer size and DataLayout::getPointerSize() in DWARF info generation
llvm-svn: 300463
2017-04-17 17:41:25 +00:00
Eric Christopher 9ea300f08d If the DIUnit has flags passed on it then have DW_AT_producer be a combination of DICompileUnit::Producer and Flags.
The darwin behavior is unchanged and will continue to use DW_AT_APPLE_flags.

Patch by Zhizhou Yang

llvm-svn: 299038
2017-03-29 23:34:27 +00:00
Adrian Prantl 5503077cde Fix PR32298 by adding an early exit to getFrameIndexExprs().
Also add an assertion for the case that there are multiple FI
expressions with a DW_OP_LLVM_fragment; which should violate internal
constraints in DbgVariable.

llvm-svn: 298518
2017-03-22 16:50:16 +00:00
Zachary Turner 82a0c97b32 Add a function to MD5 a file's contents.
In doing so, clean up the MD5 interface a little.  Most
existing users only care about the lower 8 bytes of an MD5,
but for some users that care about the upper and lower,
there wasn't a good interface.  Furthermore, consumers
of the MD5 checksum were required to handle endianness
details on their own, so it seems reasonable to abstract
this into a nicer interface that just gives you the right
value.

Differential Revision: https://reviews.llvm.org/D31105

llvm-svn: 298322
2017-03-20 23:33:18 +00:00
Adrian Prantl 956484b7b5 Replace uses of DwarfExpression::addMachineReg* with addMachineRegExpression
and mark the methods as protected.

Besides reducing the surface area of DwarfExpression, this is in
preparation for an upcoming bugfix in the DwarfExpression
implementation, for which it will be necessary to defer emitting
register operations until the rest of the expression is known.

NFC

llvm-svn: 298309
2017-03-20 21:35:09 +00:00
Adrian Prantl a63b8e8227 Rename methods in DwarfExpression to adhere to the LLVM coding guidelines.
NFC.

llvm-svn: 297966
2017-03-16 17:42:45 +00:00
Adrian Prantl 19aadf57c8 Revert "Debug Info: Add basic support for external types references."
This reverts commit r242302. External type refs of this form were
never used by any LLVM frontend so this is effectively dead code.
(They were introduced to support clang module debug info, but in the
end we came up with a better design that doesn't use this feature at
all.)

rdar://problem/25897929

Differential Revision: https://reviews.llvm.org/D30917

llvm-svn: 297684
2017-03-13 22:56:14 +00:00
Adrian Prantl 67c2442210 Debug Info: Sort frame index expressions before emitting them.
This fixes PR31381, which caused an assertion and/or invalid debug info.

This affects debug variables that have multiple fragments in the MMI
side (i.e.: in the stack frame) table.
rdar://problem/30571676

llvm-svn: 295486
2017-02-17 19:42:32 +00:00
David Blaikie b2fbb4b276 Refactor DebugHandlerBase a bit to common non-debug-having-function filtering
llvm-svn: 295354
2017-02-16 18:48:33 +00:00
David Blaikie a0e3c75187 DebugInfo: ensure type and namespace names are included in pubnames/pubtypes even when they are only present in type units
While looking to add support for placing singular types (types that will
only be emitted in one place (such as attached to a strong vtable or
explicit template instantiation definition)) not in type units (since
type units have overhead) I stumbled across that change causing an
increase in pubtypes.

Turns out we were missing some types from type units if they were only
referenced from other type units and not from the debug_info section.

This fixes that, following GCC's line of describing the offset of such
entities as the CU die (since there's no compile unit-relative offset
that would describe such an entity - they aren't in the CU). Also like
GCC, this change prefers to describe the type stub within the CU rather
than the "just use the CU offset" fallback where possible. This may give
the DWARF consumer some opportunity to find the extra info in the type
stub - though I'm not sure GDB does anything with this currently.

The size of the pubnames/pubtypes sections now match exactly with or
without type units enabled.

This nearly triples (+189%) the pubtypes section for a clang self-host
and grows pubnames by 0.07% (without compression). For a total of 8%
increase in debug info sections of the objects of a Split DWARF build
when using type units.

llvm-svn: 293971
2017-02-03 00:44:18 +00:00
Paul Robinson 5362216c36 Remove an assertion that doesn't hold when mixing -g and -gmlt through
LTO.  Replace it with a related assertion, ensuring that abstract
variables appear only in abstract scopes.
Part of PR31437.

Differential Revision: http://reviews.llvm.org/D29430

llvm-svn: 293841
2017-02-01 23:51:56 +00:00
Dehao Chen 0944a8c2ec Change debug-info-for-profiling from a TargetOption to a function attribute.
Summary: LTO requires the debug-info-for-profiling to be a function attribute.

Reviewers: echristo, mehdi_amini, dblaikie, probinson, aprantl

Reviewed By: mehdi_amini, dblaikie, aprantl

Subscribers: aprantl, probinson, ahatanak, llvm-commits, mehdi_amini

Differential Revision: https://reviews.llvm.org/D29203

llvm-svn: 293833
2017-02-01 22:45:09 +00:00
Paul Robinson a380e613f1 Remove an assertion that doesn't hold when mixing -g and -gmlt through
LTO.  Part of PR31437.

Differential Revision: http://reviews.llvm.org/D29310

llvm-svn: 293818
2017-02-01 21:54:50 +00:00
Dehao Chen 1ce8d6ca59 Add -debug-info-for-profiling to emit more debug info for sample pgo profile collection
Summary:
SamplePGO binaries built with -gmlt to collect profile. The current -gmlt debug info is limited, and we need some additional info:

* start line of all subprograms
* linkage name of all subprograms
* standalone subprograms (functions that has neither inlined nor been inlined)

This patch adds these information to the -gmlt binary. The impact on speccpu2006 binary size (size increase comparing with -g0 binary, also includes data for -g binary, which does not change with this patch):

               -gmlt(orig) -gmlt(patched) -g
433.milc       4.68%       5.40%          19.73%
444.namd       8.45%       8.93%          45.99%
447.dealII     97.43%      115.21%        374.89%
450.soplex     27.75%      31.88%         126.04%
453.povray     21.81%      26.16%         92.03%
470.lbm        0.60%       0.67%          1.96%
482.sphinx3    5.77%       6.47%          26.17%
400.perlbench  17.81%      19.43%         73.08%
401.bzip2      3.73%       3.92%          12.18%
403.gcc        31.75%      34.48%         122.75%
429.mcf        0.78%       0.88%          3.89%
445.gobmk      6.08%       7.92%          42.27%
456.hmmer      10.36%      11.25%         35.23%
458.sjeng      5.08%       5.42%          14.36%
462.libquantum 1.71%       1.96%          6.36%
464.h264ref    15.61%      16.56%         43.92%
471.omnetpp    11.93%      15.84%         60.09%
473.astar      3.11%       3.69%          14.18%
483.xalancbmk  56.29%      81.63%         353.22%
geomean        15.60%      18.30%         57.81%

Debug info size change for -gmlt binary with this patch:

433.milc       13.46%
444.namd       5.35%
447.dealII     18.21%
450.soplex     14.68%
453.povray     19.65%
470.lbm        6.03%
482.sphinx3    11.21%
400.perlbench  8.91%
401.bzip2      4.41%
403.gcc        8.56%
429.mcf        8.24%
445.gobmk      29.47%
456.hmmer      8.19%
458.sjeng      6.05%
462.libquantum 11.23%
464.h264ref    5.93%
471.omnetpp    31.89%
473.astar      16.20%
483.xalancbmk  44.62%
geomean        16.83%

Reviewers: davidxl, echristo, dblaikie

Reviewed By: echristo, dblaikie

Subscribers: aprantl, probinson, llvm-commits, mehdi_amini

Differential Revision: https://reviews.llvm.org/D25434

llvm-svn: 292457
2017-01-19 00:44:11 +00:00
Adrian Prantl 49797ca6be Refactor the DIExpression fragment query interface (NFC)
... so it becomes available to DIExpressionCursor.

llvm-svn: 290322
2016-12-22 05:27:12 +00:00
Adrian Prantl bceaaa9643 [IR] Remove the DIExpression field from DIGlobalVariable.
This patch implements PR31013 by introducing a
DIGlobalVariableExpression that holds a pair of DIGlobalVariable and
DIExpression.

Currently, DIGlobalVariables holds a DIExpression. This is not the
best way to model this:

(1) The DIGlobalVariable should describe the source level variable,
    not how to get to its location.

(2) It makes it unsafe/hard to update the expressions when we call
    replaceExpression on the DIGLobalVariable.

(3) It makes it impossible to represent a global variable that is in
    more than one location (e.g., a variable with multiple
    DW_OP_LLVM_fragment-s).  We also moved away from attaching the
    DIExpression to DILocalVariable for the same reasons.

This reapplies r289902 with additional testcase upgrades and a change
to the Bitcode record for DIGlobalVariable, that makes upgrading the
old format unambiguous also for variables without DIExpressions.

<rdar://problem/29250149>
https://llvm.org/bugs/show_bug.cgi?id=31013
Differential Revision: https://reviews.llvm.org/D26769

llvm-svn: 290153
2016-12-20 02:09:43 +00:00
Paul Robinson 2dfb688214 Allow "line 0" to be the first explicit debug location in a function.
Feedback on r289468 from Adrian Prantl.

llvm-svn: 290012
2016-12-16 23:54:33 +00:00
Adrian Prantl 73ec065604 Revert "[IR] Remove the DIExpression field from DIGlobalVariable."
This reverts commit 289920 (again).
I forgot to implement a Bitcode upgrade for the case where a DIGlobalVariable
has not DIExpression. Unfortunately it is not possible to safely upgrade
these variables without adding a flag to the bitcode record indicating which
version they are.
My plan of record is to roll the planned follow-up patch that adds a
unit: field to DIGlobalVariable into this patch before recomitting.
This way we only need one Bitcode upgrade for both changes (with a
version flag in the bitcode record to safely distinguish the record
formats).

Sorry for the churn!

llvm-svn: 289982
2016-12-16 19:39:01 +00:00
Adrian Prantl 74a835cda0 [IR] Remove the DIExpression field from DIGlobalVariable.
This patch implements PR31013 by introducing a
DIGlobalVariableExpression that holds a pair of DIGlobalVariable and
DIExpression.

Currently, DIGlobalVariables holds a DIExpression. This is not the
best way to model this:

(1) The DIGlobalVariable should describe the source level variable,
    not how to get to its location.

(2) It makes it unsafe/hard to update the expressions when we call
    replaceExpression on the DIGLobalVariable.

(3) It makes it impossible to represent a global variable that is in
    more than one location (e.g., a variable with multiple
    DW_OP_LLVM_fragment-s).  We also moved away from attaching the
    DIExpression to DILocalVariable for the same reasons.

This reapplies r289902 with additional testcase upgrades.

<rdar://problem/29250149>
https://llvm.org/bugs/show_bug.cgi?id=31013
Differential Revision: https://reviews.llvm.org/D26769

llvm-svn: 289920
2016-12-16 04:25:54 +00:00
Adrian Prantl 03c6d31a3b Revert "[IR] Remove the DIExpression field from DIGlobalVariable."
This reverts commit 289902 while investigating bot berakage.

llvm-svn: 289906
2016-12-16 01:00:30 +00:00
Adrian Prantl ce13935776 [IR] Remove the DIExpression field from DIGlobalVariable.
This patch implements PR31013 by introducing a
DIGlobalVariableExpression that holds a pair of DIGlobalVariable and
DIExpression.

Currently, DIGlobalVariables holds a DIExpression. This is not the
best way to model this:

(1) The DIGlobalVariable should describe the source level variable,
    not how to get to its location.

(2) It makes it unsafe/hard to update the expressions when we call
    replaceExpression on the DIGLobalVariable.

(3) It makes it impossible to represent a global variable that is in
    more than one location (e.g., a variable with multiple
    DW_OP_LLVM_fragment-s).  We also moved away from attaching the
    DIExpression to DILocalVariable for the same reasons.

<rdar://problem/29250149>
https://llvm.org/bugs/show_bug.cgi?id=31013
Differential Revision: https://reviews.llvm.org/D26769

llvm-svn: 289902
2016-12-16 00:36:43 +00:00
David Blaikie 38b74bf249 DebugInfo: Address non-deterministic output (iterating a SmallPtrSet) in 289697
Post-commit review feedback from Adrian Prantl.

Hopefully this fixes that up :)

llvm-svn: 289892
2016-12-15 23:37:38 +00:00
David Blaikie 3e3eb33ed7 DebugInfo: Emit ranges for functions with DISubprograms but lacking locations on any instructions
This seems more consistent, and helps tidy up/simplify some other code
in this change.

llvm-svn: 289889
2016-12-15 23:17:52 +00:00
David Blaikie b461468958 DebugInfo: Improve type safety and simplify some subprogram finalization code
This probably ended up this way aften the subprogram<>function link
inversion and debug info metadata schema changes.

llvm-svn: 289697
2016-12-14 19:38:39 +00:00
Paul Robinson 8fec3da00c [DWARF] Preserve column number when emitting 'line 0' record
Follow-up to r289256, address a FIXME to avoid resetting the column
number. This reduced .debug_line by 2.6% in a RelWithDebInfo
self-build of clang.

llvm-svn: 289620
2016-12-14 00:27:35 +00:00
Paul Robinson ac7fe5e0c4 Recommit r288212: Emit 'no line' information for interesting 'orphan' instructions.
DWARF specifies that "line 0" really means "no appropriate source
location" in the line table.  By default, use this for branch targets
and some other cases that have no specified source location, to
prevent inheriting unfortunate line numbers from physically preceding
instructions (which might be from completely unrelated source).

Updated patch allows enabling or suppressing this behavior for all
unspecified source locations.

Differential Revision: http://reviews.llvm.org/D24180

llvm-svn: 289468
2016-12-12 20:49:11 +00:00
Adrian Prantl 8fafb8d378 Fix LLVM's use of DW_OP_bit_piece in DWARF expressions.
LLVM's use of DW_OP_bit_piece is incorrect and a based on a
misunderstanding of the wording in the DWARF specification. The offset
argument of DW_OP_bit_piece refers to the offset into the location
that is on the top of the DWARF expression stack, and not an offset
into the source variable. This has since also been clarified in the
DWARF specification.

This patch fixes all uses of DW_OP_bit_piece to emit the correct
offset and simplifies the DwarfExpression class to semi-automaticaly
emit empty DW_OP_pieces to adjust the offset of the source variable,
thus simplifying the code using DwarfExpression.

While this is an incompatible bugfix, in practice I don't expect this
to be much of a problem since LLVM's old interpretation and the
correct interpretation of DW_OP_bit_piece differ only when there are
gaps in the fragmented locations of the described variables or if
individual fragments are smaller than a byte. LLDB at least won't
interpret locations with gaps in them because is has no way to present
undefined bits in a variable, and there is a high probability that an
old-form expression will be malformed when interpreted correctly,
because the DW_OP_bit_piece offset will be outside of the location at
the top of the stack.

As a nice side-effect, this patch enables us to use a more efficient
encoding for subregisters: In order to express a sub-register at a
non-zero offset we now use a DW_OP_bit_piece instead of shifting the
value into place manually.

This patch also adds missing test coverage for code paths that weren't
exercised before.

<rdar://problem/29335809>
Differential Revision: https://reviews.llvm.org/D27550

llvm-svn: 289266
2016-12-09 20:43:40 +00:00
Paul Robinson 4fa7b57a1f [DWARF] Suppress .loc directives from CFI instructions
Like DBG_VALUE, these emit nothing to the .text section, and sometimes
have no source location specified.  Just ignore them.

Differential Revision: http://reviews.llvm.org/D27492

llvm-svn: 289256
2016-12-09 19:15:32 +00:00
Adrian Prantl 941fa7588b [DIExpression] Introduce a dedicated DW_OP_LLVM_fragment operation
so we can stop using DW_OP_bit_piece with the wrong semantics.

The entire back story can be found here:
http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20161114/405934.html

The gist is that in LLVM we've been misinterpreting DW_OP_bit_piece's
offset field to mean the offset into the source variable rather than
the offset into the location at the top the DWARF expression stack. In
order to be able to fix this in a subsequent patch, this patch
introduces a dedicated DW_OP_LLVM_fragment operation with the
semantics that we used to apply to DW_OP_bit_piece, which is what we
actually need while inside of LLVM. This patch is complete with a
bitcode upgrade for expressions using the old format. It does not yet
fix the DWARF backend to use DW_OP_bit_piece correctly.

Implementation note: We discussed several options for implementing
this, including reserving a dedicated field in DIExpression for the
fragment size and offset, but using an custom operator at the end of
the expression works just fine and is more efficient because we then
only pay for it when we need it.

Differential Revision: https://reviews.llvm.org/D27361
rdar://problem/29335809

llvm-svn: 288683
2016-12-05 18:04:47 +00:00
Greg Clayton 35630c3357 This change removes the dependency on DwarfDebug that was used for DW_FORM_ref_addr by making a new DIEUnit class in DIE.cpp.
The DIEUnit class represents a compile or type unit and it owns the unit DIE as an instance variable. This allows anyone with a DIE, to get the unit DIE, and then get back to its DIEUnit without adding any new ivars to the DIE class. Why was this needed? The DIE class has an Offset that is always the CU relative DIE offset, not the "offset in debug info section" as was commented in the header file (the comment has been corrected). This is great for performance because most DIE references are compile unit relative and this means most code that accessed the DIE's offset didn't need to make it into a compile unit relative offset because it already was. When we needed to emit a DW_FORM_ref_addr though, we needed to find the absolute offset of the DIE by finding the DIE's compile/type unit. This class did have the absolute debug info/type offset and could be added to the CU relative offset to compute the absolute offset. With this change we can easily get back to a DIE's DIEUnit which will have this needed offset. Prior to this is required having a DwarfDebug and required calling:

DwarfCompileUnit *DwarfDebug::lookupUnit(const DIE *CU) const;
Now we can use the DIEUnit class to do so without needing DwarfDebug. All clients now use DIEUnit objects (the DwarfDebug stack and the DwarfLinker). A follow on patch for the DWARF generator will also take advantage of this.

Differential Revision: https://reviews.llvm.org/D27170

llvm-svn: 288399
2016-12-01 18:56:29 +00:00
Kostya Serebryany b66cb88c2e revert r288283 as it causes debug info (line numbers) to be lost in instrumented code. also revert r288299 which was a workaround for the problem.
llvm-svn: 288300
2016-12-01 02:06:56 +00:00
Matthias Braun ef331eff5a Move VariableDbgInfo from MachineModuleInfo to MachineFunction
VariableDbgInfo is per function data, so it makes sense to have it with
the function instead of the module.

This is a necessary step to have machine module passes work properly.

Differential Revision: https://reviews.llvm.org/D27186

llvm-svn: 288292
2016-11-30 23:48:50 +00:00
Paul Robinson 37a13ddb4b Recommit r288212: Emit 'no line' information for interesting 'orphan' instructions.
The LLDB tests are now ready for this patch.

DWARF specifies that "line 0" really means "no appropriate source
location" in the line table.  Use this for branch targets and some
other cases that have no specified source location, to prevent
inheriting unfortunate line numbers from physically preceding
instructions (which might be from completely unrelated source).

Differential Revision: http://reviews.llvm.org/D24180

llvm-svn: 288283
2016-11-30 22:49:55 +00:00
Paul Robinson 957ba405e8 Revert r288212 due to lldb failure.
llvm-svn: 288216
2016-11-29 23:20:35 +00:00
Paul Robinson 96de8c778b Emit 'no line' information for interesting 'orphan' instructions.
DWARF specifies that "line 0" really means "no appropriate source
location" in the line table.  Use this for branch targets and some
other cases that have no specified source location, to prevent
inheriting unfortunate line numbers from physically preceding
instructions (which might be from completely unrelated source).

Differential Revision: http://reviews.llvm.org/D24180

llvm-svn: 288212
2016-11-29 22:41:16 +00:00
Greg Clayton e65439797a Rely on a single DWARF version instead of having two copies
This patch makes AsmPrinter less reliant on DwarfDebug by relying on the DWARF version in the AsmPrinter's MCStreamer's MCContext. This allows us to remove the redundant DWARF version from DwarfDebug. It also lets us change code that used to access the AsmPrinter's DwarfDebug just to get to the DWARF version by changing the DWARF version accessor on AsmPrinter so that it grabs the version from its MCStreamer's MCContext.

Differential Revision: https://reviews.llvm.org/D27032

llvm-svn: 287839
2016-11-23 23:30:37 +00:00
Paul Robinson f428c9b298 Restructure DwarfDebug::beginInstruction(). [NFC]
Will help a pending patch.

Differential Revision: http://reviews.llvm.org/D26982

llvm-svn: 287686
2016-11-22 19:46:51 +00:00
Matthias Braun 9f15a79e5d Timer: Track name and description.
The previously used "names" are rather descriptions (they use multiple
words and contain spaces), use short programming language identifier
like strings for the "names" which should be used when exporting to
machine parseable formats.

Also removed a unused TimerGroup from Hexxagon.

Differential Revision: https://reviews.llvm.org/D25583

llvm-svn: 287369
2016-11-18 19:43:18 +00:00
Adrian Prantl 54286bda2c Simplify control flow in the the DWARF expression compiler
by refactoring common code into a DwarfExpressionCursor wrapper.

llvm-svn: 285827
2016-11-02 16:12:20 +00:00
Adrian Prantl 56527dc804 Emit DW_OP_piece also if the previous value was a constant.
This fixes a bug in the DWARF backend.

llvm-svn: 285826
2016-11-02 16:12:16 +00:00
Adrian Prantl c4fbbcf9ed Import/update constants from the DWARF 5 public review draft document.
https://reviews.llvm.org/D26051

llvm-svn: 285421
2016-10-28 17:59:50 +00:00
Mehdi Amini 732afdd09a Turn cl::values() (for enum) from a vararg function to using C++ variadic template
The core of the change is supposed to be NFC, however it also fixes
what I believe was an undefined behavior when calling:

 va_start(ValueArgs, Desc);

with Desc being a StringRef.

Differential Revision: https://reviews.llvm.org/D25342

llvm-svn: 283671
2016-10-08 19:41:06 +00:00
Dehao Chen 6e0c8446db Invoke add-discriminator at -g0 -fsample-profile
Summary: -fsample-profile needs discriminator, which will not be added if built with -g0. This patch makes sure the discriminator is added for sample-profile at -g0. A followup patch will be send out to update clang tests.

Reviewers: davidxl, dblaikie, echristo, dnovillo

Subscribers: mehdi_amini, probinson, llvm-commits

Differential Revision: https://reviews.llvm.org/D25132

llvm-svn: 283565
2016-10-07 15:21:31 +00:00
Eric Christopher 364dbe06d3 Stop calling getTargetTriple off of the AsmPrinter and constructing a
TargetTriple, just grab it off of the TargetMachine. NFC.

llvm-svn: 283001
2016-10-01 01:50:29 +00:00
Peter Collingbourne d4135bbc30 DebugInfo: New metadata representation for global variables.
This patch reverses the edge from DIGlobalVariable to GlobalVariable.
This will allow us to more easily preserve debug info metadata when
manipulating global variables.

Fixes PR30362. A program for upgrading test cases is attached to that
bug.

Differential Revision: http://reviews.llvm.org/D20147

llvm-svn: 281284
2016-09-13 01:12:59 +00:00
George Burgess IV 381fc0ee3c Make some LLVM_CONSTEXPR variables const. NFC.
This patch changes LLVM_CONSTEXPR variable declarations to const
variable declarations, since LLVM_CONSTEXPR expands to nothing if the
current compiler doesn't support constexpr. In all of the changed
cases, it looks like the code intended the variable to be const instead
of sometimes-constexpr sometimes-not.

llvm-svn: 279696
2016-08-25 01:05:08 +00:00
David Blaikie a01f295322 DebugInfo: Add flag to CU to disable emission of inline debug info into the skeleton CU
In cases where .dwo/.dwp files are guaranteed to be available, skipping
the extra online (in the .o file) inline info can save a substantial
amount of space - see the original r221306 for more details there.

llvm-svn: 279650
2016-08-24 18:29:49 +00:00
David Majnemer 0a16c22846 Use range algorithms instead of unpacking begin/end
No functionality change is intended.

llvm-svn: 278417
2016-08-11 21:15:00 +00:00
Benjamin Kramer b7d3311c77 Move helpers into anonymous namespaces. NFC.
llvm-svn: 277916
2016-08-06 11:13:10 +00:00
Benjamin Kramer 4ca41fd09e Run clang-tidy's performance-unnecessary-copy-initialization over LLVM.
No functionality change intended.

llvm-svn: 272516
2016-06-12 17:30:47 +00:00
Peter Collingbourne b326986de0 DwarfDebug: Simplify. NFC.
llvm-svn: 271360
2016-06-01 02:58:40 +00:00
Petr Hosek faef3207de [MC] Rename EmitFill to emitFill
This is to match the overloaded variants as well as the new style.

Differential Revision: http://reviews.llvm.org/D20690

llvm-svn: 271359
2016-06-01 01:59:58 +00:00
David Blaikie c53e18d93a DWARF: Omit DW_AT_APPLE attributes (except ObjC ones) when not targeting LLDB
These attributes aren't used by other debuggers (& may be confused with
other DWARF extensions) so they just waste space (about 1.5% on .dwo
file size on a random large program I tested).

We could remove the ObjC property ones too, but I figured they were
probably more necessary when trying to understand ObjC (I could be wrong
though) & so any debugger interested in working with ObjC would use
them, perhaps? (also, there are some legacy tests in Clang that test for
them - making it one of those annoying cross-project commits and/or
cleanup to refactor those tests)

llvm-svn: 270613
2016-05-24 21:19:28 +00:00
Peter Collingbourne 5973bc8a82 CodeGen: Move the call to DwarfDebug::beginModule() out of the constructor.
This gives AsmPrinter a chance to initialize its DD field before
we call beginModule(), which is about to start using it.

Differential Revision: http://reviews.llvm.org/D20413

llvm-svn: 270258
2016-05-20 19:35:35 +00:00
Peter Collingbourne 96c9ae6a20 CodeGen: Do not require a MachineFunction just to create a DIEDwarfExpression.
We are about to start using DIEDwarfExpression to create global variable
DIEs, which happens before we generate code for functions.

Differential Revision: http://reviews.llvm.org/D20412

llvm-svn: 270257
2016-05-20 19:35:17 +00:00
Rafael Espindola 78d947b4f5 Fix pr27728.
Sorry for the lack testcase. There is one in the pr, but it depends on
std::sort and the .ll version is 110 lines, so I don't think it is
wort it.

The bug was that we were sorting after adding a terminator, and the
sorting algorithm could end up putting the terminator in the middle of
the List vector.

With that we would create a Spans map entry keyed on nullptr which would
then be added to CUs and fail in that sorting.

llvm-svn: 270165
2016-05-20 00:38:28 +00:00
Rafael Espindola 0a78f8c463 clang-format. NFC.
llvm-svn: 270156
2016-05-19 23:17:37 +00:00
Adrian Prantl 6323ddf99c Debug Info: Introduce a DwarfDebug::UseDWARF2Bitfields flag
instead of having DwarfUnit query the debugger tuning options.

Follow-up commmit to r269827.
Thanks to Paul Robinson for pointing this out!

llvm-svn: 269840
2016-05-17 21:07:16 +00:00
Adrian Prantl 723ccd2790 Debug Info: Prevent DW_AT_abstract_origin from being emitted twice
for the same subprogram.

This fixes a bug where DW_AT_abstract_origin is being emitted twice for
the same subprogram if a function is both inlined and emitted in the same
translation unit, by restoring the pre-r266446 behavior.

http://reviews.llvm.org/D20072

llvm-svn: 269103
2016-05-10 19:38:51 +00:00
Amjad Aboud 72da9391f0 Reverting 268054 & 268063 as they caused PR27579.
llvm-svn: 268150
2016-04-30 01:44:07 +00:00
Amjad Aboud 293ee8bba1 Recommitted r264280 "Supporting all entities declared in lexical scope in LLVM debug info."
After fixing PR26942 in r267004.

llvm-svn: 268054
2016-04-29 16:07:55 +00:00
Duncan P. N. Exon Smith a59d3e5af8 DebugInfo: Remove MDString-based type references
Eliminate DITypeIdentifierMap and make DITypeRef a thin wrapper around
DIType*.  It is no longer legal to refer to a DICompositeType by its
'identifier:', and DIBuilder no longer retains all types with an
'identifier:' automatically.

Aside from the bitcode upgrade, this is mainly removing logic to resolve
an MDString-based reference to an actualy DIType.  The commits leading
up to this have made the implicit type map in DICompileUnit's
'retainedTypes:' field superfluous.

This does not remove DITypeRef, DIScopeRef, DINodeRef, and
DITypeRefArray, or stop using them in DI-related metadata.  Although as
of this commit they aren't serving a useful purpose, there are patchces
under review to reuse them for CodeView support.

The tests in LLVM were updated with deref-typerefs.sh, which is attached
to the thread "[RFC] Lazy-loading of debug info metadata":

  http://lists.llvm.org/pipermail/llvm-dev/2016-April/098318.html

llvm-svn: 267296
2016-04-23 21:08:00 +00:00
Paul Robinson 43d1e45347 [DWARF] Force a linkage_name on an inlined subprogram's abstract origin.
When we suppress linkage names, for a non-inlined subprogram the name
can still be found in the object-file symbol table, because we have
the code address of the subprogram.  This is not necessarily the case
for an inlined subprogram, so we still want to emit the linkage name
in the DWARF.  Put this on the abstract-origin DIE because it's common
to all inlined instances.

Differential Revision: http://reviews.llvm.org/D18706

llvm-svn: 266692
2016-04-18 22:41:41 +00:00
Adrian Prantl 75819aedf6 [PR27284] Reverse the ownership between DICompileUnit and DISubprogram.
Currently each Function points to a DISubprogram and DISubprogram has a
scope field. For member functions the scope is a DICompositeType. DIScopes
point to the DICompileUnit to facilitate type uniquing.

Distinct DISubprograms (with isDefinition: true) are not part of the type
hierarchy and cannot be uniqued. This change removes the subprograms
list from DICompileUnit and instead adds a pointer to the owning compile
unit to distinct DISubprograms. This would make it easy for ThinLTO to
strip unneeded DISubprograms and their transitively referenced debug info.

Motivation
----------

Materializing DISubprograms is currently the most expensive operation when
doing a ThinLTO build of clang.

We want the DISubprogram to be stored in a separate Bitcode block (or the
same block as the function body) so we can avoid having to expensively
deserialize all DISubprograms together with the global metadata. If a
function has been inlined into another subprogram we need to store a
reference the block containing the inlined subprogram.

Attached to https://llvm.org/bugs/show_bug.cgi?id=27284 is a python script
that updates LLVM IR testcases to the new format.

http://reviews.llvm.org/D19034
<rdar://problem/25256815>

llvm-svn: 266446
2016-04-15 15:57:41 +00:00
Adrian Prantl 3891e9e859 Drop debug info for DISubprograms that are not referenced by anything
This patch drops the debug info for all DISubprograms that are
(a) not attached to an llvm::Function and
(b) not indirectly reachable via inline scopes from any surviving Function and
(c) not reachable from a type (i.e.: member functions).

Background: I'm currently working on a patch to reverse the pointers
between DICompileUnit and DISubprogram (for more info check Duncan's RFC
on lazy-loading of debug info metadata
http://lists.llvm.org/pipermail/llvm-dev/2016-March/097419.html).
The idea is to remove the list of subprograms from DICompileUnit and
instead point to the owning compile unit from each DISubprogram.
After doing this all DISubprograms fulfilling the above criteria will be
implicitly dropped unless we go through an extra effort to preserve them.

http://reviews.llvm.org/D18477
<rdar://problem/25256815>

llvm-svn: 265876
2016-04-09 18:10:22 +00:00
Adrian Prantl 5992a72b4d Support the Nodebug emission kind for DICompileUnits.
Sample-based profiling and optimization remarks currently remove
DICompileUnits from llvm.dbg.cu to suppress the emission of debug info
from them. This is somewhat of a hack and only borderline legal IR.

This patch uses the recently introduced NoDebug emission kind in
DICompileUnit to achieve the same result without breaking the Verifier.
A nice side-effect of this change is that it is now possible to combine
NoDebug and regular compile units under LTO.

http://reviews.llvm.org/D18808
<rdar://problem/25427165>

llvm-svn: 265861
2016-04-08 22:43:03 +00:00
Adrian Prantl 3e9c88753b DwarfDebug: Support floating point constants in location lists.
This patch closes a gap in the DWARF backend that caused LLVM to drop
debug info for floating point variables that were constant for part of
their scope. Floating point constants are emitted as one or more
DW_OP_constu joined via DW_OP_piece.

This fixes a regression caught by the LLDB testsuite that I introduced
in r262247 when we stopped blindly expanding the range of singular
DBG_VALUEs to span the entire scope and started to emit location lists
with accurate ranges instead.

Also deletes a now-impossible testcase (debug-loc-empty-entries).

<rdar://problem/25448338>

llvm-svn: 265760
2016-04-08 00:38:37 +00:00
Adrian Prantl b939a25707 Move the DebugEmissionKind enum from DIBuilder into DICompileUnit.
This mostly cosmetic patch moves the DebugEmissionKind enum from DIBuilder
into DICompileUnit. DIBuilder is not the right place for this enum to live
in — a metadata consumer should not have to include DIBuilder.h.
I also added a Verifier check that checks that the emission kind of a
DICompileUnit is actually legal.

http://reviews.llvm.org/D18612
<rdar://problem/25427165>

llvm-svn: 265077
2016-03-31 23:56:58 +00:00
Reid Kleckner 01bc66a8ce Revert "Recommitted r263424 "Supporting all entities declared in lexical scope in LLVM debug info." After fixing PR26942 (the fix is included in this commit)."
This reverts commit r264280.

This broke building Chromium for iOS. We'll upload a reproducer to the
PR soon.

llvm-svn: 264334
2016-03-24 20:38:49 +00:00
David Blaikie 0b214e4a2a [debuginfo] Include dwo_name in the split unit to improve dwp diagnostics
When multiple DWP files are merged together and duplicate DWO IDs are
found it's currently difficult to give an actionable error message - the
DW_AT_name of the CU could be provided, but might be identical (if the
same source file is built into two different configurations), which
doesn't help the user identify the problem.

When no intermediate DWP files are generated, the path to the two DWO
files could be provided - but is lost once the DWOs are merged into a
DWP.

So, include the name of the DWO (dwo_name) in the split file so that
collissions involving a source CU from a DWP can be better diagnosed.

(improvements to llvm-dwp using this to come shortly)

llvm-svn: 264316
2016-03-24 18:37:08 +00:00
Amjad Aboud 6ff7e10052 Recommitted r263424 "Supporting all entities declared in lexical scope in LLVM debug info."
After fixing PR26942 (the fix is included in this commit).

Differential Revision: http://reviews.llvm.org/D18350

llvm-svn: 264280
2016-03-24 13:30:16 +00:00
Benjamin Kramer 1082fa66a5 Revert "Recommitted r261633 "Supporting all entities declared in lexical scope in LLVM debug info." After fixing PR26715 at r263379."
This reverts commit r263424. Breaks self-host.

llvm-svn: 263437
2016-03-14 14:58:36 +00:00
Amjad Aboud ab0378b16c Recommitted r261633 "Supporting all entities declared in lexical scope in LLVM debug info."
After fixing PR26715 at r263379.

llvm-svn: 263424
2016-03-14 12:03:20 +00:00
Adrian Prantl dba58fbdd9 Improve the debug output of DwarfDebug::buildLocationList().
llvm-svn: 262265
2016-02-29 22:28:22 +00:00
Adrian Prantl fb2add2be1 Fix PR26585 by improving the promotion of DBG_VALUEs to DW_AT_locations.
When a variable is described by a single DBG_VALUE instruction we can
often use a more efficient inline DW_AT_location instead of using a
location list.

This commit makes the heuristic that decides when to apply this
optimization stricter by also verifying that the DBG_VALUE is live at the
entry of the function (instead of just checking that it is valid until
the end of the function).

<rdar://problem/24611008>

llvm-svn: 262247
2016-02-29 19:49:46 +00:00
Adrian Prantl 693e8de0fa fix typo in comment
llvm-svn: 262236
2016-02-29 17:06:46 +00:00
Hans Wennborg d3661cd140 Revert r261633 "Supporting all entities declared in lexical scope in LLVM debug info."
This and the corresponding Clang change caused PR26715.

llvm-svn: 261671
2016-02-23 19:17:03 +00:00
Amjad Aboud fc8f296782 Supporting all entities declared in lexical scope in LLVM debug info.
Differential Revision: http://reviews.llvm.org/D15976

llvm-svn: 261633
2016-02-23 13:36:51 +00:00
Peter Collingbourne 7c384ccea2 DwarfDebug: emit type units immediately.
Rather than storing type units in a vector and emitting them at the end
of code generation, emit them immediately and destroy them, reclaiming the
memory we were using for their DIEs.

In one benchmark carried out against Chromium's 50 largest (by bitcode
file size) translation units, total peak memory consumption with type units
decreased by median 17%, or by 7% when compared against disabling type units.

Tested using check-{llvm,clang}, the GDB 7.5 test suite (with
'-fdebug-types-section') and by eyeballing llvm-dwarfdump output on those
Chromium translation units with split DWARF both disabled and enabled, and
verifying that the only changes were to addresses and abbreviation ordering.

Differential Revision: http://reviews.llvm.org/D17118

llvm-svn: 260578
2016-02-11 19:57:46 +00:00
Reid Kleckner f9c275fe0a [codeview] Describe int local variables using .cv_def_range
Summary:
Refactor common value, scope, and label tracking logic out of DwarfDebug
into a common base class called DebugHandlerBase.

Update an old LLVM IR test case to avoid an assertion in LexicalScopes.

Reviewers: dblaikie, majnemer

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D16931

llvm-svn: 260432
2016-02-10 20:55:49 +00:00
Keno Fischer 6c1e47a66b [DWARFDebug] Fix another case of overlapping ranges
Summary:
In r257979, I added code to ensure that we wouldn't merge DebugLocEntries if
the pieces they describe overlap. Unfortunately, I failed to cover the case,
where there may have multiple active Expressions in the entry, in which case we
need to make sure that no two values overlap before we can perform the merge.

This fixed PR26148.

Reviewers: aprantl
Differential Revision: http://reviews.llvm.org/D16742

llvm-svn: 259696
2016-02-03 21:13:33 +00:00
Eugene Zelenko ecefe5a81f Fix Clang-tidy readability-redundant-control-flow warnings; other minor fixes.
Differential revision: http://reviews.llvm.org/D16793

llvm-svn: 259539
2016-02-02 18:20:45 +00:00
Amjad Aboud 8bbce8ad8e Improved macro emission in dwarf.
Changed emitting offset of macinfo entry into compiler unit DIE to use "addSectionLabel" method rather than explicitly calculating size/offset of macro entry.

Differential Revision: http://reviews.llvm.org/D16292

llvm-svn: 259358
2016-02-01 14:09:41 +00:00
Amjad Aboud c077841492 Fixed few comments.
llvm-svn: 258658
2016-01-24 08:18:55 +00:00
Keno Fischer bc0cb11eb2 [DwarfDebug] Don't merge DebugLocEntries if their pieces overlap
Summary:
Later in DWARF emission we check that DebugLocEntries have
non-overlapping pieces, so we should create any such entries
by merging here.

Fixes PR26163.

Reviewers: aprantl
Differential Revision: http://reviews.llvm.org/D16249

llvm-svn: 257979
2016-01-16 01:15:32 +00:00
Keno Fischer f8eb6a1414 [DwarfDebug] Move MergeValues to .cpp, NFC
llvm-svn: 257977
2016-01-16 01:11:33 +00:00
Dimitry Andric 2c36421337 Turn off lldb debug tuning by default for FreeBSD
Summary:
In rL242338, debugger tuning was introduced, and the tuning for FreeBSD
was set to lldb by default.  However, for the foreseeable future we
still need to default to gdb tuning, since lldb is not ready for all of
FreeBSD's architectures, and some system tools (like objcopy, etc) have
not yet been adapted to cope with the lldb tuned format, which has
.apple sections.

Therefore, let FreeBSD use gdb by default for now.

Reviewers: emaste, probinson

Subscribers: llvm-commits, emaste

Differential Revision: http://reviews.llvm.org/D15966

llvm-svn: 257103
2016-01-07 22:09:12 +00:00
Amjad Aboud d7cfb48485 Added support for macro emission in dwarf (supporting DWARF version 4).
Differential Revision: http://reviews.llvm.org/D15495

llvm-svn: 257060
2016-01-07 14:28:20 +00:00
Paul Robinson 6c27a2c40e Set debugger tuning from TargetOptions (NFC)
Differential Revision: http://reviews.llvm.org/D15427

llvm-svn: 255810
2015-12-16 19:58:30 +00:00
Peter Collingbourne d4bff30370 DI: Reverse direction of subprogram -> function edge.
Previously, subprograms contained a metadata reference to the function they
described. Because most clients need to get or set a subprogram for a given
function rather than the other way around, this created unneeded inefficiency.

For example, many passes needed to call the function llvm::makeSubprogramMap()
to build a mapping from functions to subprograms, and the IR linker needed to
fix up function references in a way that caused quadratic complexity in the IR
linking phase of LTO.

This change reverses the direction of the edge by storing the subprogram as
function-level metadata and removing DISubprogram's function field.

Since this is an IR change, a bitcode upgrade has been provided.

Fixes PR23367. An upgrade script for textual IR for out-of-tree clients is
attached to the PR.

Differential Revision: http://reviews.llvm.org/D14265

llvm-svn: 252219
2015-11-05 22:03:56 +00:00
Ivan Krasin 298639a5fd Move imported entities into DwarfCompilationUnit to speed up LTO linking.
Summary:
In particular, this CL speeds up the official Chrome linking with LTO by
1.8x.

See more details in https://crbug.com/542426

Reviewers: dblaikie

Subscribers: jevinskie

Differential Revision: http://reviews.llvm.org/D13918

llvm-svn: 251353
2015-10-26 21:36:35 +00:00
Benjamin Kramer 7fa42c8a8c [AsmPrinter] Prune dead code. NFC.
I left all (dead) print and dump methods in place.

llvm-svn: 250433
2015-10-15 17:16:32 +00:00
Michael Kuperstein 2b3c16ca17 Do not assert on first non-prologue instruction being a CFI directive.
llvm-svn: 249668
2015-10-08 07:48:49 +00:00
Adrian Prantl 77fefeba37 Debug Info: Emit the dwo_name only in skeleton CUs, not in DWOs.
llvm-svn: 248340
2015-09-22 23:21:00 +00:00
Adrian Prantl deef90d7f5 DwarfDebug: Emit dwo_id+dwo_name for DICompileUnits that provide a dwoId.
For module debugging clang emits prefabricated skeleton compile units
that can be recognized by a nonzero dwoId.

llvm-svn: 247626
2015-09-14 22:10:22 +00:00
Paul Robinson 78046b49a9 Make DW_AT_[MIPS_]linkage_name optional, and off by default for SCE.
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
2015-08-11 21:36:45 +00:00
Frederic Riss a5ab8443c1 [MC/Dwarf] Allow to specify custom parameters for linetable emission.
NFC patch for current users, but llvm-dsymutil will use the new
functionality to adapt to the input linetable.

Based on a patch by Adrian Prantl.

llvm-svn: 244318
2015-08-07 15:14:08 +00:00
Reid Kleckner 12d2c12023 If the "CodeView" module flag is set, emit codeview instead of DWARF
Summary:
Emit both DWARF and CodeView if "CodeView" and "Dwarf Version" module
flags are set.

Reviewers: majnemer

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D11756

llvm-svn: 244158
2015-08-05 22:26:20 +00:00
Duncan P. N. Exon Smith ed013cd221 DI: Remove DW_TAG_arg_variable and DW_TAG_auto_variable
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
2015-07-31 18:58:39 +00:00
Duncan P. N. Exon Smith 099ea1c9ae DI: Strengthen block-byref cast to DIDerivedType, NFC
This code is visiting the members of a block-byref, and we know those
are all `DIDerivedType`.  Strengthen the cast.

llvm-svn: 243138
2015-07-24 18:58:32 +00:00
Duncan P. N. Exon Smith 6ac940db19 DI: Only DICompositeType has getElements(), NFC
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
2015-07-24 18:17:17 +00:00
Paul Robinson b9de106d04 Add a "debugger tuning" concept that allows us to fine-tune how we
emit debug info, according to the preferences of the different
debuggers used on various targets.
Darwin and FreeBSD default to tuning for LLDB; PS4 defaults to tuning for
the SCE (Sony Computer Entertainment) debugger.  All others default to GDB.

Differential Revision: http://reviews.llvm.org/D8506

llvm-svn: 242338
2015-07-15 22:04:54 +00:00
Adrian Prantl ee5feafc0f Debug Info: Add basic support for external types references.
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
2015-07-15 17:01:41 +00:00
David Blaikie d51dea67b3 Revert "[DWARF] Fix debug info generation for function static variables, typedefs, and records"
Caused PR24008

This reverts commit 37cb5f1c2db9f42d29f26b215585f56bb64ae4f5.

llvm-svn: 241176
2015-07-01 18:07:16 +00:00
Michael Kuperstein 01e8185c31 [DWARF] Fix debug info generation for function static variables, typedefs, and records
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
2015-07-01 12:33:11 +00:00
Duncan P. N. Exon Smith 3a73d9e067 AsmPrinter: Don't emit empty .debug_loc entries
If we don't know how to represent a .debug_loc entry, skip the entry
entirely rather than emitting an empty one.  Similarly, if a .debug_loc
list has no entries, don't create the list.

We still want to create the variables, just in an optimized-out form
that doesn't have a DW_AT_location.

llvm-svn: 240244
2015-06-21 16:54:56 +00:00
Duncan P. N. Exon Smith e6cc531b1a AsmPrinter: Rewrite initialization of DbgVariable, NFC
There are three types of `DbgVariable`:
  - alloca variables, created based on the MMI table,
  - register variables, created based on DBG_VALUE instructions, and
  - optimized-out variables.

This commit reconfigures `DbgVariable` to make it easier to tell which
kind we have, and make initialization a little clearer.

For MMI/alloca variables, `FrameIndex.size()` must always equal
`Expr.size()`, and there shouldn't be an `MInsn`.  For register
variables (with a `MInsn`), `FrameIndex` must be empty, and `Expr`
should have 0 or 1 element depending on whether it has a complex
expression (registers with multiple locations use `DebugLocListIndex`).
Optimized-out variables shouldn't have any of these fields.

Moreover, this separates DBG_VALUE initialization until after the
variable is created, simplifying logic in a future commit that changes
`collectVariableInfo()` to stop creating empty .debug_loc entries/lists.

llvm-svn: 240243
2015-06-21 16:50:43 +00:00
Rafael Espindola 857546e7e0 Rename and improve emitSectionOffset.
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
2015-06-16 23:22:02 +00:00
David Blaikie 0ebe35b278 Revert "[DWARF] Fix a few corner cases in expression emission"
This reverts commit r239380 due to apparently GDB regressions:
http://lab.llvm.org:8011/builders/clang-x86_64-ubuntu-gdb-75/builds/22562

llvm-svn: 239420
2015-06-09 18:01:51 +00:00
Keno Fischer e34147ce2f [DWARF] Fix a few corner cases in expression emission
Summary: I noticed an object file with `DW_OP_reg4 DW_OP_breg4 0` as a DWARF expression,
which I traced to a missing break (and `++I`) in this code snippet.
While I was at it, I also added support for a few other corner cases
along the same lines that I could think of.

Test Plan: Hand-crafted test case to exercises these cases is included.

Reviewers: echristo, dblaikie, aprantl

Reviewed By: aprantl

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D10302

llvm-svn: 239380
2015-06-09 01:53:59 +00:00
Duncan P. N. Exon Smith e7e1d0c706 Reapply "AsmPrinter: Change DIEValue to be stored by value"
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
2015-05-27 22:14:58 +00:00
Duncan P. N. Exon Smith 583bc03829 Revert "AsmPrinter: Change DIEValue to be stored by value"
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
2015-05-27 19:30:27 +00:00
Duncan P. N. Exon Smith 7735b48a8b AsmPrinter: Change DIEValue to be stored by value
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
2015-05-27 19:22:50 +00:00
Adrian Prantl 6f8c1b6be6 Use "auto &" in range-based for-loop and remove the extra braces.
llvm-svn: 238243
2015-05-26 20:06:51 +00:00
Adrian Prantl 757073191a Fix a use-after-free in a DEBUG output.
llvm-svn: 238242
2015-05-26 20:06:48 +00:00
Duncan P. N. Exon Smith f4599942fb AsmPrinter: Use DwarfStringPoolEntry in DwarfAccelTable, NFC
This is just an API change, but it prepares to stop using
`EmitLabelDifference()` when possible.

llvm-svn: 238118
2015-05-24 16:44:32 +00:00
Rafael Espindola 0709a7bd1a Move alignment from MCSectionData to MCSection.
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
2015-05-21 19:20:38 +00:00
Pete Cooper a05c082866 Don't generate comments in the DebugLocStream unless required. NFC.
The ByteStreamer here wasn't taking account of whether the asm streamer was text based and verbose.  Only with that combination should we emit comments.

This change makes sure that we only actually convert a Twine to a string using Twine::str() if we need the comment.  This saves about 10000 small allocations on a test case involving the verify-use_list-order bitcode going through llc with debug info.

Note, this is NFC as the comments would ultimately never be emitted unless required.

Reviewed by Duncan Exon Smith and David Blaikie.

llvm-svn: 237851
2015-05-20 22:51:27 +00:00
Pete Cooper 477300d333 Revert "Add bool to DebugLocDwarfExpression to control emitting comments."
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
2015-05-20 22:37:48 +00:00
Pete Cooper 35522001fa Add bool to DebugLocDwarfExpression to control emitting comments.
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
2015-05-20 19:50:03 +00:00
Jim Grosbach 6f482000e9 MC: Clean up method names in MCContext.
The naming was a mish-mash of old and new style. Update to be consistent
with the new. NFC.

llvm-svn: 237594
2015-05-18 18:43:14 +00:00
Duncan P. N. Exon Smith 653c1099b4 DwarfDebug: Emit number of bytes in .debug_loc entry directly
Emit the number of bytes in a `.debug_loc` entry directly.  The old code
created temp labels (expensive), emitted the difference between them,
and then emitted one on each side of the relevant bytes.

(I'm looking at `llc` memory usage on `verify-uselistorder.lto.opt.bc`
(the optimized version of ld64's `-save-temps` when linking the
`verify-uselistorder` executable in an LTO bootstrap).  I've hacked
`MCContext::Allocate()` to just call `malloc()` instead of using the
`BumpPtrAllocator` so that the heap profile is easier to read.  As far
as peak memory is concerned, `MCContext::Allocate()` is equivalent to a
leak, since it only gets freed at process teardown.

In my heap profile, this patch drops memory usage of
`DwarfDebug::emitDebugLoc()` from 132.56 MB (11.4%) down to 29.86 MB
(2.7%) at peak memory.  Some of that must be noise from `SmallVector`
(or other) allocations -- peak memory only dropped from 1160 MB down to
1100 MB -- but this nevertheless shaves 5% off the top.)

llvm-svn: 236629
2015-05-06 19:11:20 +00:00
David Blaikie 72d03efa6d DebugInfo: Use low_pc relative debug_ranges under fission when the CU has a low_pc
Seems we were setting the base address on the wrong DwarfCompileUnit
object so it wasn't being used when generating the ranges.

llvm-svn: 236377
2015-05-02 02:31:49 +00:00
Duncan P. N. Exon Smith a9308c49ef IR: Give 'DI' prefix to debug info metadata
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
2015-04-29 16:38:44 +00:00
Lang Hames 9ff69c8f4d [AsmPrinter] Make AsmPrinter's OutStreamer member a unique_ptr.
AsmPrinter owns the OutStreamer, so an owning pointer makes sense here. Using a
reference for this is crufty.

llvm-svn: 235752
2015-04-24 19:11:51 +00:00
Duncan P. N. Exon Smith 60635e39b6 DebugInfo: Drop rest of DIDescriptor subclasses
Delete the remaining subclasses of (the already deleted) `DIDescriptor`.
Part of PR23080.

llvm-svn: 235404
2015-04-21 18:44:06 +00:00
Duncan P. N. Exon Smith 2fbe13540a DebugInfo: Delete subclasses of DIScope
Delete subclasses of (the already defunct) `DIScope`, updating users to
use the raw pointers from the `Metadata` hierarchy directly.

llvm-svn: 235356
2015-04-20 22:10:08 +00:00
Duncan P. N. Exon Smith c62468859a DebugInfo: Delete old subclasses of DIType
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
2015-04-20 21:17:32 +00:00
Duncan P. N. Exon Smith 698df36ab7 DwarfUnit: Split MDSubroutineType version of constructTypeDIE()
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
2015-04-20 21:04:33 +00:00
Duncan P. N. Exon Smith 9928a909c6 DebugInfo: Remove DIType
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
2015-04-20 18:52:06 +00:00
Duncan P. N. Exon Smith 848af387d8 DebugInfo: Remove typedefs for DITypeRef, etc.
Remove typedefs for type refs:

  - DITypeRef => MDTypeRef
  - DIScopeRef => MDScopeRef
  - DIDescriptorRef => DebugNodeRef

llvm-svn: 235323
2015-04-20 18:20:03 +00:00
Duncan P. N. Exon Smith 364a3005f2 AsmPrinter: Create a unified .debug_loc stream
This commit removes `DebugLocList` and replaces it with
`DebugLocStream`.

  - `DebugLocEntry` no longer contains its byte/comment streams.
  - The `DebugLocEntry` list for a variable/inlined-at pair is allocated
    on the stack, and released right after `DebugLocEntry::finalize()`
    (possible because of the refactoring in r231023).  Now, only one
    list is in memory at a time now.
  - There's a single unified stream for the `.debug_loc` section that
    persists, stored in the new `DebugLocStream` data structure.

The last point is important: this collapses the nested `SmallVector<>`s
from `DebugLocList` into unified streams.  We previously had something
like the following:

    vec<tuple<Label, CU,
              vec<tuple<BeginSym, EndSym,
                        vec<Value>,
                        vec<char>,
                        vec<string>>>>>

A `SmallVector` can avoid allocations, but is statically fairly large
for a vector: three pointers plus the size of the small storage, which
is the number of elements in small mode times the element size).
Nesting these is expensive, since an inner vector's size contributes to
the element size of an outer one.  (Nesting any vector is expensive...)

In the old data structure, the outer vector's *element* size was 632B,
excluding allocation costs for when the middle and inner vectors
exceeded their small sizes.  312B of this was for the "three" pointers
in the vector-tree beneath it.  If you assume 1M functions with an
average of 10 variable/inlined-at pairs each (in an LTO scenario),
that's almost 6GB (besides inner allocations), with almost 3GB for the
"three" pointers.

This came up in a heap profile a little while ago of a `clang -flto -g`
bootstrap, with `DwarfDebug::collectVariableInfo()` using something like
10-15% of the total memory.

With this commit, we have:

    tuple<vec<tuple<Label, CU, Offset>>,
          vec<tuple<BeginSym, EndSym, Offset, Offset>>,
          vec<char>,
          vec<string>>

The offsets are used to create `ArrayRef` slices of adjacent
`SmallVector`s.  This reduces the number of vectors to four (unrelated
to the number of variable/inlined-at pairs), and caps the number of
allocations at the same number.

Besides saving memory and limiting allocations, this is NFC.

I don't know my way around this code very well yet, but I wonder if we
could go further: why stream to a side-table, instead of directly to the
output stream?

llvm-svn: 235229
2015-04-17 21:34:47 +00:00
Duncan P. N. Exon Smith c0f7dd72b7 AsmPrinter: Store MDExpression directly instead of MDNode, NFC
Clean up `DebugLocEntry::Value::Expression`'s type while I'm messing
around in here anyway.

llvm-svn: 235203
2015-04-17 16:36:10 +00:00
Duncan P. N. Exon Smith 546c8be967 AsmPrinter: Stop storing MDLocalVariable in DebugLocEntry
Stop storing the `MDLocalVariable` in the `DebugLocEntry::Value`s.  We
generate the list of `DebugLocEntry`s separately for each
variable/inlined-at pair, so the variable never actually changes here.

This is effectively NFC (aside from saving some memory and CPU time).

llvm-svn: 235202
2015-04-17 16:33:37 +00:00
Duncan P. N. Exon Smith fba25d6e9b AsmPrinter: Calculate type upfront for location lists, NFC
We can calculate the variable type up front before calling
`DebugLocEntry::finalize()`.  In fact, since we only care about the type
if it's an `MDBasicType`, don't even bother resolving it using the type
identifier map.

llvm-svn: 235201
2015-04-17 16:28:58 +00:00
Duncan P. N. Exon Smith 78a9527062 AsmPrinter: Simplify logic for debug info intrinsics' !dbg attachments
These are required, so just assume they're there.

llvm-svn: 235138
2015-04-16 22:12:59 +00:00
Duncan P. N. Exon Smith b0b0e4958b DebugInfo: DIRef<> => TypedDebugNodeRef<>
Delete `DIRef<>`, and replace the remaining uses of it with
`TypedDebugNodeRef<>`.  To minimize code churn, I've added typedefs from
`MDTypeRef` to `DITypeRef` (etc.).

llvm-svn: 235071
2015-04-16 02:24:01 +00:00
Duncan P. N. Exon Smith b273d06b63 DebugInfo: Gut DIScope, DIEnumerator and DISubrange
The only class the still has API left is `DIDescriptor` itself.

llvm-svn: 235067
2015-04-16 01:37:00 +00:00
Duncan P. N. Exon Smith b105564015 DebugInfo: Gut DIType and subclasses
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
2015-04-16 01:01:28 +00:00
Duncan P. N. Exon Smith 35ef22cf53 DebugInfo: Gut DICompileUnit and DIFile
Continuing gutting `DIDescriptor` subclasses; this edition,
`DICompileUnit` and `DIFile`.  In the name of PR23080.

llvm-svn: 235055
2015-04-15 23:19:27 +00:00
Duncan P. N. Exon Smith 768d96ca6f DebugInfo: factor out dead variable in NDEBUG from r235050
Caught by the lld bot:

http://lab.llvm.org:8011/builders/lld-x86_64-darwin13/builds/9832

llvm-svn: 235052
2015-04-15 22:42:43 +00:00
Duncan P. N. Exon Smith 62e0f454a0 DebugInfo: Remove 'inlinedAt:' field from MDLocalVariable
Remove 'inlinedAt:' from MDLocalVariable.  Besides saving some memory
(variables with it seem to be single largest `Metadata` contributer to
memory usage right now in -g -flto builds), this stops optimization and
backend passes from having to change local variables.

The 'inlinedAt:' field was used by the backend in two ways:

 1. To tell the backend whether and into what a variable was inlined.
 2. To create a unique id for each inlined variable.

Instead, rely on the 'inlinedAt:' field of the intrinsic's `!dbg`
attachment, and change the DWARF backend to use a typedef called
`InlinedVariable` which is `std::pair<MDLocalVariable*, MDLocation*>`.
This `DebugLoc` is already passed reliably through the backend (as
verified by r234021).

This commit removes the check from r234021, but I added a new check
(that will survive) in r235048, and changed the `DIBuilder` API in
r235041 to require a `!dbg` attachment whose 'scope:` is in the same
`MDSubprogram` as the variable's.

If this breaks your out-of-tree testcases, perhaps the script I used
(mdlocalvariable-drop-inlinedat.sh) will help; I'll attach it to PR22778
in a moment.

llvm-svn: 235050
2015-04-15 22:29:27 +00:00
Duncan P. N. Exon Smith 537b4a8159 DebugInfo: Gut DISubprogram and DILexicalBlock*
Gut the `DIDescriptor` wrappers around `MDLocalScope` subclasses.  Note
that `DILexicalBlock` wraps `MDLexicalBlockBase`, not `MDLexicalBlock`.

llvm-svn: 234850
2015-04-14 03:40:37 +00:00
Duncan P. N. Exon Smith 7348ddaa74 DebugInfo: Gut DIVariable and DIGlobalVariable
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
2015-04-14 02:22:36 +00:00
Duncan P. N. Exon Smith 571baebacb DebugInfo: Inline DIVariable::isBlockByrefVariable() into its callers
I don't think this API is helping much.  Change the callers to call
`MDType::isBlockByrefStruct()` directly.

llvm-svn: 234837
2015-04-14 01:59:58 +00:00
Duncan P. N. Exon Smith de8e427394 DebugInfo: Gut DIObjCProperty and DIImportedEntity
Gut a couple more classes in the DIDescriptor hierarchy.  Leave behind
an implicit conversion to `DIDescriptor`, the old base class.

llvm-svn: 234836
2015-04-14 01:46:44 +00:00
Duncan P. N. Exon Smith 6a0320a991 DebugInfo: Gut DIExpression
Completely gut `DIExpression`, turning it into a simple wrapper around
`MDExpression *`.  There are two bits of magic left:

  - It's constructed from `const MDExpression*` but convertible to
    `MDExpression*`.
  - It's default-constructed to `nullptr`.

Otherwise, it should behave quite like a raw pointer.  Once I've done
the same to the rest of the `DIDescriptor` subclasses, I'll come back to
delete them entirely (and update call sites as necessary to deal with
the missing magic).

llvm-svn: 234832
2015-04-14 01:12:42 +00:00
Duncan P. N. Exon Smith c82570b68b Reapply "Verifier: Check for incompatible bit piece expressions"
This reverts commit r234717, reapplying r234698 (in spirit).

As described in r234717, the original `Verifier` check had a
use-after-free.  Instead of storing pointers to "interesting" debug info
intrinsics whose bit piece expressions should be verified once we have
typerefs, do a second traversal.  I've added a testcase to catch the
`llc` crasher.

Original commit message:

    Verifier: Check for incompatible bit piece expressions

    Convert an assertion into a `Verifier` check.  Bit piece expressions
    must fit inside the variable, and mustn't be the entire variable.
    Catching this in the verifier will help us find bugs sooner, and makes
    `DIVariable::getSizeInBits()` dead code.

llvm-svn: 234776
2015-04-13 18:53:11 +00:00
Duncan P. N. Exon Smith 5cd454161c Revert "Verifier: Check for incompatible bit piece expressions"
This reverts commit r234698.

This caused a use-after-free: `QueuedBitPieceExpressions` holds onto
references to `DbgInfoIntrinsic`s and references them past where they're
deleted (this is because the verifier is run as a function pass, and
then `verifyTypeRefs()` is called during `doFinalization()`).

I'll include a reduced crasher for `llc` when I recommit the check.

llvm-svn: 234717
2015-04-13 00:06:28 +00:00
Duncan P. N. Exon Smith 5ad6ff76dc Verifier: Check for incompatible bit piece expressions
Convert an assertion into a `Verifier` check.  Bit piece expressions
must fit inside the variable, and mustn't be the entire variable.
Catching this in the verifier will help us find bugs sooner, and makes
`DIVariable::getSizeInBits()` dead code.

llvm-svn: 234698
2015-04-11 19:58:35 +00:00
Duncan P. N. Exon Smith 000fa2c646 DebugInfo: Remove DITypedArray<>, replace with typedefs
Replace all uses of `DITypedArray<>` with `MDTupleTypedArrayWrapper<>`
and `MDTypeRefArray`.  The APIs are completely different, but the
provided functionality is the same: treat an `MDTuple` as if it's an
array of a particular element type.

To simplify this patch a bit, I've temporarily typedef'ed
`DebugNodeArray` to `DIArray` and `MDTypeRefArray` to `DITypeArray`.
I've also temporarily conditionalized the accessors to check for null --
eventually these should be changed to asserts and the callers should
check for null themselves.

There's a tiny accompanying patch to clang.

llvm-svn: 234290
2015-04-07 04:14:33 +00:00
Duncan P. N. Exon Smith 76c9184434 DebugInfo: Remove special iterators from DIExpression
Remove special iterators from `DIExpression` in favour of same in
`MDExpression`.  There should be no functionality change here.

Note that the APIs are slightly different: `getArg(unsigned)` counts
from 0, not 1, in the `MDExpression` version of the iterator.

llvm-svn: 234285
2015-04-07 03:45:57 +00:00
Duncan P. N. Exon Smith e686f1591f CodeGen: Stop using DIDescriptor::is*() and auto-casting
Same as r234255, but for lib/CodeGen and lib/Target.

llvm-svn: 234258
2015-04-06 23:27:40 +00:00
Duncan P. N. Exon Smith a5099dce62 DebugInfo: Remove DIDescriptor::Verify()
Remove `DIDescriptor::Verify()` and the `Verify()`s from subclasses.
They had already been gutted, and just did an `isa<>` check.

In a couple of cases I've temporarily dropped the check entirely, but
subsequent commits are going to disallow conversions to the
`DIDescriptor`s directly from `MDNode`, so the checks will come back in
another form soon enough.

llvm-svn: 234201
2015-04-06 19:49:39 +00:00
Duncan P. N. Exon Smith 3bef6a3803 CodeGen: Assert that inlined-at locations agree
As a follow-up to r234021, assert that a debug info intrinsic variable's
`MDLocalVariable::getInlinedAt()` always matches the
`MDLocation::getInlinedAt()` of its `!dbg` attachment.

The goal here is to get rid of `MDLocalVariable::getInlinedAt()`
entirely (PR22778), but I'll let these assertions bake for a while
first.

If you have an out-of-tree backend that just broke, you're probably
attaching the wrong `DebugLoc` to a `DBG_VALUE` instruction.  The one
you want is the location that was attached to the corresponding
`@llvm.dbg.declare` or `@llvm.dbg.value` call that you started with.

llvm-svn: 234038
2015-04-03 19:20:26 +00:00
Duncan P. N. Exon Smith 33af7a8f50 LexicalScopes: Use debug info hierarchy pervasively
Pervasively use the types provided by the debug info hierarchy rather
than `MDNode` in `LexicalScopes`.

I noticed (again, I guess, based on comments in the implementation?)
that `DILexicalBlockFile::getScope()` returns something different from
`DILexicalBlockFile::getContext()`.  I created a local helper for
getting the same logic from `MDLexicalBlockFile` called
`getScopeOfScope()`.  I still don't really understand it, but I've added
some FIXMEs and I'll come back to it (I suspect the way we encode these
objects isn't really ideal).

Note that my previous commit r233610 accidentally changed behaviour in
`findLexicalScope()` -- it transitioned from a call to
`DILexicalBlockFile::getScope()` to `MDLexicalBlockFile::getScope()`
(sounds right, doesn't it?) -- so I've fixed that as a drive-by.  No
tests failed with my error, so it looks like we're missing some coverage
here... when I come back to understand the logic, I'll see if I can add
some.

Other than the fix to `findLexicalScope()`, no functionality change.

llvm-svn: 233640
2015-03-30 23:21:21 +00:00
Duncan P. N. Exon Smith fd07a2af23 DwarfDebug: Avoid creating new DebugLocs in the backend
Don't use `DebugLoc::getFnDebugLoc()`, which creates new `MDLocation`s,
in the backend.  We just want to grab the subprogram here anyway.

llvm-svn: 233601
2015-03-30 21:32:28 +00:00
Duncan P. N. Exon Smith 9dffcd04f7 CodeGen: Use the new DebugLoc API, NFC
Update lib/CodeGen (and lib/Target) to use the new `DebugLoc` API.

llvm-svn: 233582
2015-03-30 19:14:47 +00:00
Rafael Espindola f2b408c64e Refactor how passes get a symbol at the end of a section.
There is now a canonical symbol at the end of a section that different
passes can request.

This also allows us to assert that we don't switch back to a section whose
end symbol has already been printed.

llvm-svn: 233026
2015-03-23 21:22:04 +00:00
Benjamin Kramer 799003bf8c Re-sort includes with sort-includes.py and insert raw_ostream.h where it's used.
llvm-svn: 232998
2015-03-23 19:32:43 +00:00
Duncan P. N. Exon Smith d3a057733f DwarfDebug: Check for null DebugLocs
`DL` might be null, so check for that before using accessors.  A WIP
patch to make `DIDescriptors` more strict fails otherwise.

As a bonus, I think the logic is easier to follow now (despite the extra
nesting depth).

llvm-svn: 232836
2015-03-20 19:37:03 +00:00
Rafael Espindola 9ab09237dc Centralize the handling of unique ids for temporary labels.
Before this patch code wanting to create temporary labels for a given entity
(function, cu, exception range, etc) had to keep its own counter to have stable
symbol names.

createTempSymbol would still add a suffix to make sure a new symbol was always
returned, but it kept a single counter. Because of that, if we were to use
just createTempSymbol("cu_begin"), the label could change from cu_begin42 to
cu_begin43 because some other code started using temporary labels.

Simplify this by just keeping one counter per prefix and removing the various
specialized counters.

llvm-svn: 232535
2015-03-17 20:07:06 +00:00
Rafael Espindola c0eb4de58d Convert the last 4 users of GetTempSymbol to createTempSymbol.
Despite using the same name these are unrelated.

llvm-svn: 232485
2015-03-17 14:58:47 +00:00
Rafael Espindola 5345e420c4 Convert the easy cases of GetTempSymbol to createTempSymbol.
In these cases no code was depending on GetTempSymbol finding an existing
symbol.

llvm-svn: 232478
2015-03-17 14:22:31 +00:00
Rafael Espindola 51067848e7 Remove dead code. NFC.
llvm-svn: 232472
2015-03-17 13:09:01 +00:00
Eric Christopher 5ab3b79ba8 Use the cached subtarget off of the machine function.
llvm-svn: 232128
2015-03-13 00:38:19 +00:00
Rafael Espindola f1a13f5ad5 Print section start labels when first switching to the section.
This is less brittle and avoids polluting the start of the file with every
debug section.

llvm-svn: 231898
2015-03-11 00:51:37 +00:00
Rafael Espindola 6b9998b3eb Create symbols marking the start of a section earlier.
This lets us pass the symbol to the constructor and avoid the mutable field.

This also opens the way for outputting the symbol only when needed, instead
of outputting them at the start of the file.

llvm-svn: 231859
2015-03-10 22:00:25 +00:00
Adrian Prantl 51233680ae Change the datatype of DwarfExpression::Emit(Un)Signed to (u)int64_t
so it matches the one used by ByteStreamer::Emit(U|S)LEB128.

llvm-svn: 231823
2015-03-10 19:23:37 +00:00
Rafael Espindola 063d725fd7 Store an optional section start label in MCSection.
This makes code that uses section relative expressions (debug info) simpler and
less brittle.

This is still a bit awkward as the symbol is created late and has to be
stored in a mutable field.

I will move the symbol creation earlier in the next patch.

llvm-svn: 231802
2015-03-10 16:58:10 +00:00
Rafael Espindola 3c066d1da3 Remove effectively dead code.
Switching back and forth between sections does nothing (other than producing
larger .s files).

llvm-svn: 231790
2015-03-10 14:48:01 +00:00
Rafael Espindola 4f4ef15ade Use a MapVector instead of an extra sort.
This also has the advantage of not depending on the brittle getLabelBeginName.

llvm-svn: 231714
2015-03-09 22:08:37 +00:00
Rafael Espindola 14862d3e37 Don't prime the section map.
This was just creating unused labels for .text when the module had no
functions.

llvm-svn: 231694
2015-03-09 20:09:58 +00:00
Rafael Espindola 07c03d316d Use the existing begin and end symbol for debug info.
llvm-svn: 231338
2015-03-05 02:05:42 +00:00
Paul Robinson 49e38965dc Turn off .debug_pubnames/pubtypes for PS4.
Differential Revision: http://reviews.llvm.org/D8067

llvm-svn: 231322
2015-03-05 00:08:27 +00:00
Paul Robinson 78cc0821f0 Support standard DWARF TLS opcode; Darwin and PS4 use it.
Differential Revision: http://reviews.llvm.org/D8018

llvm-svn: 231286
2015-03-04 20:55:11 +00:00
Frederic Riss 9412d63f68 Move emitDIE and emitAbbrevs to AsmPrinter. NFC.
(They are called emitDwarfDIE and emitDwarfAbbrevs in their new home)

llvm-dsymutil wants to reuse that code, but it doesn't have a DwarfUnit or
a DwarfDebug object to call those. It has access to an AsmPrinter though.

Having emitDIE in the AsmPrinter also removes the DwarfFile dependency
on DwarfDebug, and thus the patch drops that field.

Differential Revision: http://reviews.llvm.org/D8024

llvm-svn: 231210
2015-03-04 02:30:17 +00:00
Dario Domizioli 5f7008a688 Fix PR22750: non-determinism causes assertion failure in DWARF generation
The cause of the issue is the interaction of two factors:
1) When generating a DW_TAG_imported_declaration DIE which imports another 
   imported declaration, the code in AsmPrinter/DwarfCompileUnit.cpp 
   asserts that the second imported declaration must already have a DIE.
2) There is a non-determinism in the order in which imported declarations
   within the same scope are processed.
Because of the non-determinism (2), it is possible that an imported 
declaration is processed before another one it depends on, breaking the 
assumption in (1).

The source of the non-determinism is that the imported declaration 
DIDescriptors are sorted by scope in DwarfDebug::beginModule(); however that
sort is not a stable_sort, therefore the order of the declarations within 
the same scope is not preserved. The attached patch changes the std::sort to
a std::stable_sort and it fixes the problem.

Test omitted due to it being non-deterministic and depending on the
implementation of std::sort.

llvm-svn: 231100
2015-03-03 18:40:53 +00:00
Adrian Prantl 92da14b244 Refactor DebugLocDWARFExpression so it doesn't require access to the
TargetRegisterInfo. DebugLocEntry now holds a buffer with the raw bytes
of the pre-calculated DWARF expression.

Ought to be NFC, but it does slightly alter the output format of the
textual assembly.

This reapplies 230930 without the assertion in DebugLocEntry::finalize()
because not all Machine registers can be lowered into DWARF register
numbers and floating point constants cannot be expressed.

llvm-svn: 231023
2015-03-02 22:02:33 +00:00
Rui Ueyama 3206b79d53 Use read{16,32,64}{le,be}() instead of *reinterpret_cast<u{little,big}{16,32,64}_t>().
llvm-svn: 231016
2015-03-02 21:19:12 +00:00
Adrian Prantl 2185aa179d Revert "Refactor DebugLocDWARFExpression so it doesn't require access to the"
This reverts commit 230975 to investigate buildbot breakage.

llvm-svn: 231004
2015-03-02 20:01:54 +00:00
Adrian Prantl d50bca7314 Refactor DebugLocDWARFExpression so it doesn't require access to the
TargetRegisterInfo. DebugLocEntry now holds a buffer with the raw bytes
of the pre-calculated DWARF expression.

Ought to be NFC, but it does slightly alter the output format of the
textual assembly.

This reapplies 230930 with a relaxed assertion in DebugLocEntry::finalize()
that allows for empty DWARF expressions for constant FP values.

llvm-svn: 230975
2015-03-02 17:21:06 +00:00
Nico Weber 968ceddca9 Revert r230930, it caused PR22747.
llvm-svn: 230932
2015-03-02 04:37:11 +00:00
Adrian Prantl e2c9e64532 Refactor DebugLocDWARFExpression so it doesn't require access to the
TargetRegisterInfo. DebugLocEntry now holds a buffer with the raw bytes
of the pre-calculated DWARF expression.

Ought to be NFC, but it does slightly alter the output format of the
textual assembly.

llvm-svn: 230930
2015-03-02 02:38:18 +00:00
Rafael Espindola e8fd00dab0 Simplify arange output.
Move SectionMap to its only user (emitDebugARanges) and
reorder to save a call to sort.

llvm-svn: 230693
2015-02-26 22:02:02 +00:00
Eric Christopher d4e723f2cf Used the cached subtarget off of the MachineFunction.
llvm-svn: 230078
2015-02-20 22:36:11 +00:00
Duncan P. N. Exon Smith 57bab0bc97 AsmPrinter: Take range in DwarfExpression::AddExpression(), NFC
Previously `DwarfExpression::AddExpression()` relied on
default-constructing the end iterators for `DIExpression` -- once the
operands are represented explicitly via `MDExpression` (instead of via
the strange `StringRef` navigator in `DIHeaderIterator`) this won't
work.  Explicitly take an iterator for the end of the range.

llvm-svn: 229572
2015-02-17 22:30:56 +00:00
Eric Christopher ffc5ff32d1 80-column fixups.
llvm-svn: 229527
2015-02-17 20:02:28 +00:00
Duncan P. N. Exon Smith b474937929 AsmPrinter: Stop creating DebugLocs
While looking at a heap profile of a clang LTO bootstrap with -g, I
noticed that 2.2% of memory in an `llvm-lto` of clang is from calling
`DebugLoc::get()` in `collectVariableInfo()` (accounting for ~40% of
memory used for `MDLocation`s).

I suspect this was introduced by r226736, whose goal was to prevent
uniquing of `DebugLoc`s (goal achieved, if so).

There's no reason we need a `DebugLoc` here at all -- it was just being
used for (in)convenient API -- so the fix is to pass the scope and
inlined-at directly to `LexicalScopes::findInlinedScope()`.

llvm-svn: 229459
2015-02-17 00:02:27 +00:00
Adrian Prantl ca7e470221 Debug Info: Support variables that are described by more than one MMI
table entry. This happens when SROA splits up an alloca and the resulting
allocas cannot be lowered to SSA values because their address is passed
to a function.

Fixes PR22502.

llvm-svn: 228764
2015-02-10 23:18:28 +00:00
Adrian Prantl 27bd01f71c Debug info: Use DW_OP_bit_piece instead of DW_OP_piece in the
intermediate representation. This
- increases consistency by using the same granularity everywhere
- allows for pieces < 1 byte
- DW_OP_piece didn't actually allow storing an offset.

Part of PR22495.

llvm-svn: 228631
2015-02-09 23:57:15 +00:00
Duncan P. N. Exon Smith b407bb2789 DebugInfo: Remove DW_TAG_constant
Remove handling for DW_TAG_constant.  We started producing it in
r110656, but reverted that in r110876 without dropping the support.
Finish the job.

llvm-svn: 228623
2015-02-09 22:48:04 +00:00
Rafael Espindola 6ffb1d7e3c Move simple case earlier and use a continue.
llvm-svn: 227841
2015-02-02 19:22:51 +00:00
Saleem Abdulrasool fc07c72674 CodeGen: drive-by formatting clean ups
Minor tweaks to whitespace formatting that I noticed was off.  NFC.

llvm-svn: 227014
2015-01-24 20:19:45 +00:00
Adrian Prantl 5883af3faa Remove support for DIVariable's FlagIndirectVariable and expect
frontends to use a DIExpression with a DW_OP_deref instead.

This is not only a much more natural place for this informationl; there
is also a technical reason: The FlagIndirectVariable is used to mark a
variable that is turned into a reference by virtue of the calling
convention; this happens for example to aggregate return values.
The inliner, for example, may actually need to undo this indirection to
correctly represent the value in its new context. This is impossible to
implement because the DIVariable can't be safely modified. We can however
safely construct a new DIExpression on the fly.

llvm-svn: 226476
2015-01-19 17:57:29 +00:00
Chandler Carruth d9903888d9 [cleanup] Re-sort all the #include lines in LLVM using
utils/sort_includes.py.

I clearly haven't done this in a while, so more changed than usual. This
even uncovered a missing include from the InstrProf library that I've
added. No functionality changed here, just mechanical cleanup of the
include order.

llvm-svn: 225974
2015-01-14 11:23:27 +00:00
Adrian Prantl 092d9489ed Debug Info: Move the complex expression handling (=the remainder) of
emitDebugLocValue() into DwarfExpression.

Ought to be NFC, but it actually uncovered a bug in the debug-loc-asan.ll
testcase. The testcase checks that the address of variable "y" is stored
at [RSP+16], which also lines up with the comment.
It also check(ed) that the *value* of "y" is stored in RDI before that,
but that is actually incorrect, since RDI is the very value that is
stored in [RSP+16]. Here's the assembler output:

	movb	2147450880(%rcx), %r8b
	#DEBUG_VALUE: bar:y <- RDI
	cmpb	$0, %r8b
	movq	%rax, 32(%rsp)          # 8-byte Spill
	movq	%rsi, 24(%rsp)          # 8-byte Spill
	movq	%rdi, 16(%rsp)          # 8-byte Spill
.Ltmp3:
	#DEBUG_VALUE: bar:y <- [RSP+16]

Fixed the comment to spell out the correct register and the check to
expect an address rather than a value.

Note that the range that is emitted for the RDI location was and is still
wrong, it claims to begin at the function prologue, but really it should
start where RDI is first assigned.

llvm-svn: 225851
2015-01-13 23:39:11 +00:00
Adrian Prantl 0a3bfdbd37 cleanup.
llvm-svn: 225848
2015-01-13 23:11:51 +00:00
Adrian Prantl 66f2595845 Debug Info: Move support for constants into DwarfExpression.
Move the declaration of DebugLocDwarfExpression into DwarfExpression.h
because it needs to be accessed from AsmPrinterDwarf.cpp and DwarfDebug.cpp

NFC.

llvm-svn: 225734
2015-01-13 00:04:06 +00:00
Frederic Riss e541e0b327 Make DIE.h a public CodeGen header.
dsymutil would like to use all the AsmPrinter/MCStreamer infrastructure
to stream out the DWARF. In order to do so, it will reuse the DIE object
and so this header needs to be public.

The interface exposed here has some corners that cannot be used without a
DwarfDebug object, but clients that want to stream Dwarf can just avoid
these.

Differential Revision: http://reviews.llvm.org/D6695

llvm-svn: 225208
2015-01-05 21:29:41 +00:00
David Blaikie aeaa5bf55e DebugInfo: Omit is_stmt from line table entries on the same line.
GCC does this for non-zero discriminators and since GCC doesn't produce
column info, that was the only place it comes up there. For LLVM, since
we can emit discriminators and/or column info, it makes more sense to
invert the condition and just test for changes in line number.

This should resolve at least some of the GDB 7.5 test suite failures
created by recent Clang changes that increase the location fidelity
(which, since Clang defaults to including column info on Linux by
default created a bunch of cases that confused GDB).

In theory we could do this better/differently by grouping actual source
statements together in a similar manner to the way lexical scopes are
handled but given that GDB isn't really in a position to consume that (&
users are probably somewhat used to different lines being different
'statements') this seems the safest and cheapest change. (I'm concerned
that doing this 'right' would bloat the debugloc data even further -
something Duncan's working hard to address)

llvm-svn: 225011
2014-12-30 22:47:13 +00:00
Adrian Prantl b9fa945d51 ARM/AArch64: Attach the FrameSetup MIFlag to CFI instructions.
Debug info marks the first instruction without the FrameSetup flag
as being the end of the function prologue. Any CFI instructions in the
middle of the function prologue would cause debug info to end the prologue
too early and worse, attach the line number of the CFI instruction, which
incidentally is often 0.

llvm-svn: 224294
2014-12-16 00:20:49 +00:00
Ekaterina Romanova 90ff20d8f5 A fix for PR21176.
DW_OP_const <const> doesn't describe a constant value, but a value at a constant address. 
The proper way to describe a constant value is DW_OP_constu <const>, DW_OP_stack_value. 
Added DW_OP_stack_value to the stack. 

Marked incorrect-variable-debugloc1.ll to xfail for PowerPC64, while the the failure (PR21881) 
is being investigated. 

llvm-svn: 224098
2014-12-12 05:11:47 +00:00
Ekaterina Romanova 75fd123967 Reverting commit 223981, because the test that I added (incorrect-variable-debugloc1.ll) failed for llvm-ppc64.
The test is failing for llvm-ppc64 because for this platform the location list is not being generated at all (most likely because of the bug in PPC code optimization or generation). I will file a bug agains PPC compiler, but meanwhile, until PPC bug is fixed, I will have to revert my change.  

llvm-svn: 224000
2014-12-11 06:22:35 +00:00
Ekaterina Romanova ceeaba7932 A fix for PR21176.
DW_OP_const <const> doesn't describe a constant value, but a value at a constant address.
The proper way to describe a constant value is DW_OP_constu <const>, DW_OP_stack_value.

Added DW_OP_stack_value to the stack.

-This line, and those below, will be ignored--

M    lib/CodeGen/AsmPrinter/DwarfDebug.cpp
A    test/DebugInfo/incorrect-variable-debugloc1.ll

llvm-svn: 223981
2014-12-10 23:19:56 +00:00
David Blaikie 70573dcd9f Update SetVector to rely on the underlying set's insert to return a pair<iterator, bool>
This is to be consistent with StringSet and ultimately with the standard
library's associative container insert function.

This lead to updating SmallSet::insert to return pair<iterator, bool>,
and then to update SmallPtrSet::insert to return pair<iterator, bool>,
and then to update all the existing users of those functions...

llvm-svn: 222334
2014-11-19 07:49:26 +00:00
Frederic Riss 3a6b354b3e Fix emission of Dwarf accelerator table when there are multiple CUs.
The DIE offset in the accel tables is an offset relative to the start
of the debug_info section, but we were encoding the offset to the
start of the containing CU.

llvm-svn: 221837
2014-11-12 23:48:14 +00:00
Duncan P. N. Exon Smith de36e8040f Revert "IR: MDNode => Value"
Instead, we're going to separate metadata from the Value hierarchy.  See
PR21532.

This reverts commit r221375.
This reverts commit r221373.
This reverts commit r221359.
This reverts commit r221167.
This reverts commit r221027.
This reverts commit r221024.
This reverts commit r221023.
This reverts commit r220995.
This reverts commit r220994.

llvm-svn: 221711
2014-11-11 21:30:22 +00:00
Duncan P. N. Exon Smith c5754a65e6 IR: MDNode => Value: NamedMDNode::getOperator()
Change `NamedMDNode::getOperator()` from returning `MDNode *` to
returning `Value *`.  To reduce boilerplate at some call sites, add a
`getOperatorAsMDNode()` for named metadata that's expected to only
return `MDNode` -- for now, that's everything, but debug node named
metadata (such as llvm.dbg.cu and llvm.dbg.sp) will soon change.  This
is part of PR21433.

Note that there's a follow-up patch to clang for the API change.

llvm-svn: 221375
2014-11-05 18:16:03 +00:00
David Blaikie 3a443c29b9 Provide gmlt-like inline scope information in the skeleton CU to facilitate symbolication without needing the .dwo files
Clang -gsplit-dwarf self-host -O0, binary increases by 0.0005%, -O2,
binary increases by 25%.

A large binary inside Google, split-dwarf, -O0, and other internal flags
(GDB index, etc) increases by 1.8%, optimized build is 35%.

The size impact may be somewhat greater in .o files (I haven't measured
that much - since the linked executable -O0 numbers seemed low enough)
due to relocations. These relocations could be removed if we taught the
llvm-symbolizer to handle indexed addressing in the .o file (GDB can't
cope with this just yet, but GDB won't be reading this info anyway).
Also debug_ranges could be shared between .o and .dwo, though ideally
debug_ranges would get a schema that could used index(+offset)
addressing, and move to the .dwo file, then we'd be back to sharing
addresses in the address pool again.

But for now, these sizes seem small enough to go ahead with this.

Verified that no other DW_TAGs are produced into the .o file other than
subprograms and inlined_subroutines.

llvm-svn: 221306
2014-11-04 22:12:25 +00:00
David Blaikie 5b02a19f90 Use common range handling for the CU's ranges
This generalizes the range handling for ranges in both the skeleton and
full unit, laying the foundation for the addition of more ranges (rather
than just the CU's special case) in the skeleton CU with fission+gmlt.

llvm-svn: 221202
2014-11-03 23:10:59 +00:00
David Blaikie 542616d47c Push the CURangeList down into the skeleton CU (where available) rather than the full CU
So that it may be shared between skeleton/full compile unit, for CU
ranges and other ranges to be added for fission+gmlt.

(at some point we might want some kind of object shared between the
skeleton and full compile units for all those things we only want one of
in that scope, rather than having the full unit always look through to
the skeleton... - alternatively, we might be able to have the skeleton
pointer (or another, separate pointer) point to the skeleton or to the
unit itself in non-fission, so we don't have to special case its
absence)

llvm-svn: 221186
2014-11-03 21:52:56 +00:00
David Blaikie ce343492ee Add DwarfCompileUnit::BaseAddress to track the base address used by relative addressing in debug_ranges and debug_loc
This is one of a few steps to generalize range handling to include the
CU range (thus the CU's range list will be moved into the range list
list, losing track of the base address in the process), which means
generalizing ranges from both the skeleton and full unit under fission.

And... then I can used that generalized support for ranges in
fission+gmlt where there'll be a bunch more ranges in the skeleton.

llvm-svn: 221182
2014-11-03 21:15:30 +00:00
David Blaikie bc532b44a0 Sink DwarfUnit::CURanges into DwarfCompileUnit
llvm-svn: 221161
2014-11-03 16:40:43 +00:00
David Blaikie 4aa49b2054 Formatting
llvm-svn: 221095
2014-11-02 08:52:37 +00:00
David Blaikie cafd962d97 Add DwarfUnit::isDwoUnit and use it to generalize string creation
Currently we only need to emit skeleton strings into the CU header and
we do this by explicitly calling "addLocalString". With gmlt-in-fission,
we'll be emitting a bunch of other strings from other codepaths where
it's not statically known that these strings will be local or not.

Introduce a virtual function to indicate whether this unit is a DWO unit
or not (I'm not sure if we have a good term for this, the
opposite/alternative to 'skeleton' unit) and use that to generalize the
string emission logic so that strings can be correctly emitted in both
the skeleton and dwo unit when in split dwarf mode.

And to demonstrate that this works, switch the existing special callers
of addLocalString in the skeleton builder to addString - and they still
work. Yay.

llvm-svn: 221094
2014-11-02 08:51:37 +00:00
David Blaikie 192b45c1ef DebugInfo: Sink accelerator table lists down (GlobalNames/Types) into DwarfCompileUnit
llvm-svn: 221083
2014-11-02 06:16:39 +00:00
David Blaikie 27e35f2302 Drop DwarfCompileUnit::getLocalLabel* in favor of just mapping through the skeleton explicitly.
Confusing to do this two different ways - I'm not too wedded to either
one, but here goes.

llvm-svn: 221076
2014-11-02 01:21:43 +00:00
David Blaikie 983bfea0d0 Remove DwarfUnit::LabelEnd in favor of computing the length of the section directly
This was a compile-unit specific label (unused in type units) and seems
unnecessary anyway when we can more easily directly compute the size of
the compile unit.

llvm-svn: 221067
2014-11-01 23:07:14 +00:00
David Blaikie a34568b220 Sink DwarfUnit::SectionSym into DwarfCompileUnit as it's only needed/used there.
llvm-svn: 221062
2014-11-01 20:06:28 +00:00
David Blaikie a8be0a794f And... fix the build some more.
llvm-svn: 221036
2014-11-01 01:15:24 +00:00
David Blaikie 1998a2e789 Just iterate the DwarfCompileUnits rather than trying to filter them out of the list of all units.
llvm-svn: 221034
2014-11-01 01:11:19 +00:00
David Blaikie bbad0bbb2f Add '*' to auto variable that is a pointer, as per the coding conventions.
llvm-svn: 221033
2014-11-01 01:03:39 +00:00
David Blaikie a33cd6aa27 Add DwarfCompileUnit::getSkeleton that returns DwarfCompileUnit* to avoid having to cast from DwarfUnit* on every call.
llvm-svn: 221031
2014-11-01 00:50:34 +00:00
David Blaikie 1d96cc2ff3 Sink some of DwarfDebug::collectDeadVariables down into DwarfCompileUnit.
llvm-svn: 221010
2014-10-31 22:30:30 +00:00
David Blaikie 49be5b357b Sink most of DwarfDebug::constructAbstractSubprogramScopeDIE into DwarfCompileUnit
llvm-svn: 221005
2014-10-31 21:57:02 +00:00
David Blaikie ff468a5e0b Minimize the scope of some variables, NFC.
llvm-svn: 220759
2014-10-28 02:57:26 +00:00
David Blaikie 80e5b1ebd1 DebugInfo: Sink DwarfDebug::ScopeVariables down into DwarfFile
(part of refactoring to allow subprogram emission in both the skeleton
and main units to enable -gmlt-like data to be included in the skeleton
for live inlined backtracing purposes)

llvm-svn: 220578
2014-10-24 17:57:34 +00:00
David Blaikie 0dc623c232 Remove DwarfDebug::FirstCU as it has no use
It was only being used as a flag to identify the lack of debug info from
within endModule - use the section labels for that instead.

llvm-svn: 220575
2014-10-24 17:53:38 +00:00
David Blaikie f4c504e03c DebugInfo: Remove DwarfDebug::addScopeVariable now that it's just a trivial wrapper
llvm-svn: 220542
2014-10-24 00:43:47 +00:00
David Blaikie 1dd573db45 DebugInfo: Remove DwarfDebug::CurrentFnArguments since we have to handle argument ordering of other arguments (abstract arguments) in the same way and already have code for that too.
While refactoring this code I was confused by both the name I had
introduced (addNonArgumentVariable... but it has all this logic to
handle argument numbering and keep things in order?) and by the
redundancy. Seems when I fixed the misordered inlined argument handling,
I didn't realize it was mostly redundant with the argument ordering code
(which I may've also written, I'm not sure). So let's just rely on the
more general case.

The only oddity in output this produces is that it means when we emit
all the variables for the current function, we don't track when we've
finished the argument variables and are about to start the local
variables and insert DW_AT_unspecified_parameters (for varargs
functions) there. Instead it ends up after the local variables, scopes,
etc. But this isn't invalid and doesn't cause DWARF consumers problems
that I know of... so we'll just go with that because it makes the code
nice & simple.

(though, let's see what the buildbots have to say about this - *crosses
fingers*)

There will be some cleanup commits to follow to remove the now trivial
wrappers, etc.

llvm-svn: 220527
2014-10-23 22:27:50 +00:00
David Blaikie 3b5c84008d DebugInfo: Sink DwarfDebug::addNonArgumentScopeVariable into DwarfFile.
llvm-svn: 220520
2014-10-23 22:04:30 +00:00
David Blaikie f299947bfa [DebugInfo] Sink DwarfDebug::addCurrentFnArgument down into DwarfFile.
Variable handling will be sunk into DwarfFile so that abstract variables
and the like can be shared across multiple CUs (to handle cross-CU
inlining, for example).

llvm-svn: 220453
2014-10-23 00:16:05 +00:00
David Blaikie 2b22b1e9a2 [DebugInfo] Add DwarfDebug& to DwarfFile.
Use the DwarfDebug in one function that previously took it as a
parameter, and lay the foundation for use this for other operations
coming soon.

llvm-svn: 220452
2014-10-23 00:16:03 +00:00
David Blaikie 263a008525 [DebugInfo] Remove LexicalScopes::isCurrentFunctionScope and CSE a use of LexicalScopes::getCurrentFunctionScope
Now that we're sure the only root (non-abstract) scope is the current
function scope, there's no need for isCurrentFunctionScope, the property
can be tested directly instead.

llvm-svn: 220451
2014-10-23 00:06:27 +00:00
David Blaikie e75f963c61 Revert some parts of r196288 that were confusing and untested.
If we figure out why they should be here, let's add some testing of some
kind so we can better demonstrate why it's needed.

llvm-svn: 219694
2014-10-14 17:12:02 +00:00
Adrian Prantl 049d21caea Add an assertion about the integrity of the iterator.
Broken parent scope pointers in inlined DIVariables can cause
ensureAbstractVariableIsCreated to insert new abstract scopes, thus
invalidating the iterator in this loop and leading to hard-to-debug
crashes. Useful when manually reducing IR for testcases.

llvm-svn: 219628
2014-10-13 20:44:58 +00:00
David Blaikie 7d6f29d1ee Simplify a few uses of DwarfDebug::SPMap
llvm-svn: 219510
2014-10-10 16:59:52 +00:00
David Blaikie 4191cbce8c Sink the per-CU part of DwarfDebug::finishSubprogramDefinitions into DwarfCompileUnit.
llvm-svn: 219477
2014-10-10 06:39:29 +00:00
David Blaikie 58410f241e Sink most of DwarfDebug::constructAbstractSubprogramScopeDIE down into DwarfCompileUnit.
llvm-svn: 219476
2014-10-10 06:39:26 +00:00
David Blaikie 9ab48849ad Avoid unnecessary map lookup/insertion.
llvm-svn: 219466
2014-10-10 03:09:38 +00:00
David Blaikie 73cc705a37 Remove unused parameter
llvm-svn: 219440
2014-10-09 20:36:27 +00:00
David Blaikie 78b65b6f2c Sink DwarfDebug::createAndAddScopeChildren down into DwarfCompileUnit.
llvm-svn: 219437
2014-10-09 20:26:15 +00:00
David Blaikie 1d072348cf Sink DwarfDebug::constructSubprogramScopeDIE down into DwarfCompileUnit
llvm-svn: 219436
2014-10-09 20:21:36 +00:00
David Blaikie 8b2fdb83c5 Sink DwarfDebug::createScopeChildrenDIE down into DwarfCompileUnit.
llvm-svn: 219422
2014-10-09 18:24:28 +00:00
David Blaikie 4a1a44e3bf Sink DwarfDebug.cpp::constructVariableDIE into DwarfCompileUnit.
llvm-svn: 219419
2014-10-09 17:56:39 +00:00
David Blaikie 0fbf8bdb08 Sink DwarfDebug::constructLexicalScopeDIE into DwarfCompileUnit
llvm-svn: 219414
2014-10-09 17:08:42 +00:00
David Blaikie 01b48a84dc Sink DwarfDebug::constructInlinedScopeDIE into DwarfCompileUnit
This introduces access to the AbstractSPDies map from DwarfDebug so
DwarfCompileUnit can access it. Eventually this'll sink down to
DwarfFile, but it'll still be generically accessible - not much
encapsulation to provide it. (constructInlinedScopeDIE could stay
further up, in DwarfFile to avoid exposing this - but I don't think
that's particularly better)

llvm-svn: 219411
2014-10-09 16:50:53 +00:00
David Blaikie de12375c96 Push DwarfDebug::attachRangesOrLowHighPC down into DwarfCompileUnit
llvm-svn: 219372
2014-10-09 00:21:42 +00:00
David Blaikie 524002004d Sink DwarfDebug::addScopeRangeList down into DwarfCompileUnit
(& add a few accessors/make a couple of things public for this - it's a
bit of a toss-up, but I think I prefer it this way, keeping some more of
the meaty code down in DwarfCompileUnit - if only to make for smaller
implementation files, etc)

I think we could simplify range handling a bit if we removed the range
lists from each unit and just put a single range list on DwarfDebug,
similar to address pooling.

llvm-svn: 219370
2014-10-09 00:11:39 +00:00
David Blaikie 6c0ee4ece3 Sink and coalesce DwarfDebug.cpp::addSectionLabel and DwarfUnit::addSectionLabel down into DwarfCompileUnit::addSectionLabel
llvm-svn: 219351
2014-10-08 22:46:27 +00:00
David Blaikie f76aeaec66 DebugInfo: The rest of pushing DwarfDebug::constructScopeDIE down into DwarfCompileUnit
Funnily enough, I copied it, but didn't actually remove the original in
r219345. Let's do that.

llvm-svn: 219346
2014-10-08 22:23:10 +00:00
David Blaikie febfafd13a DebugInfo: Sink constructImportedEntityDIE down into DwarfUnit from DwarfDebug.
It was just calling a bunch of DwarfUnit functions anyway, as can be
seen by the simplification of removing "TheCU" from all the function
calls in the implementation.

llvm-svn: 219103
2014-10-06 05:37:24 +00:00
David Blaikie 60b8662ea7 Remove unused map
This became unnecessary/unused in r208636

llvm-svn: 219085
2014-10-05 16:31:13 +00:00
David Blaikie cda2aa823e Sink DwarfDebug::updateSubprogramScopeDIE into DwarfCompileUnit
This requires exposing some of the current function state from
DwarfDebug. I hope there's not too much of that to expose as I go
through all the functions, but it still seems nicer to expose singular
data down to multiple consumers, than have consumers expose raw mapping
data structures up to DwarfDebug for building subprograms.

Part of a series of refactoring to allow subprograms in both the
skeleton and dwo CUs under Fission.

llvm-svn: 219060
2014-10-04 16:24:00 +00:00
David Blaikie 14499a7d68 Sink DwarfDebug::attachLowHighPC into DwarfCompileUnit
One of many things to sink down into DwarfCompileUnit to allow handling
of subprograms in both the skeleton and dwo CU under Fission.

llvm-svn: 219058
2014-10-04 15:58:47 +00:00
David Blaikie 37c5231051 Move DwarfCompileUnit from DwarfUnit.h to its own header (DwarfCompileUnit.h)
In preparation for sinking all the subprogram emission code down from
DwarfDebug into DwarfCompileUnit, this will avoid bloating
DwarfUnit.h/cpp greatly and make concerns a bit more clear/isolated.

(sinking this handling down is part of the work to handle emitting
minimal subprograms for -gmlt-like data into the skeleton CU under
fission)

llvm-svn: 219057
2014-10-04 15:49:50 +00:00
Adrian Prantl 87b7eb9d0f Move the complex address expression out of DIVariable and into an extra
argument of the llvm.dbg.declare/llvm.dbg.value intrinsics.

Previously, DIVariable was a variable-length field that has an optional
reference to a Metadata array consisting of a variable number of
complex address expressions. In the case of OpPiece expressions this is
wasting a lot of storage in IR, because when an aggregate type is, e.g.,
SROA'd into all of its n individual members, the IR will contain n copies
of the DIVariable, all alike, only differing in the complex address
reference at the end.

By making the complex address into an extra argument of the
dbg.value/dbg.declare intrinsics, all of the pieces can reference the
same variable and the complex address expressions can be uniqued across
the CU, too.
Down the road, this will allow us to move other flags, such as
"indirection" out of the DIVariable, too.

The new intrinsics look like this:
declare void @llvm.dbg.declare(metadata %storage, metadata %var, metadata %expr)
declare void @llvm.dbg.value(metadata %storage, i64 %offset, metadata %var, metadata %expr)

This patch adds a new LLVM-local tag to DIExpressions, so we can detect
and pretty-print DIExpression metadata nodes.

What this patch doesn't do:

This patch does not touch the "Indirect" field in DIVariable; but moving
that into the expression would be a natural next step.

http://reviews.llvm.org/D4919
rdar://problem/17994491

Thanks to dblaikie and dexonsmith for reviewing this patch!

Note: I accidentally committed a bogus older version of this patch previously.
llvm-svn: 218787
2014-10-01 18:55:02 +00:00
Adrian Prantl b458dc2eee Revert r218778 while investigating buldbot breakage.
"Move the complex address expression out of DIVariable and into an extra"

llvm-svn: 218782
2014-10-01 18:10:54 +00:00
Adrian Prantl 25a7174e7a Move the complex address expression out of DIVariable and into an extra
argument of the llvm.dbg.declare/llvm.dbg.value intrinsics.

Previously, DIVariable was a variable-length field that has an optional
reference to a Metadata array consisting of a variable number of
complex address expressions. In the case of OpPiece expressions this is
wasting a lot of storage in IR, because when an aggregate type is, e.g.,
SROA'd into all of its n individual members, the IR will contain n copies
of the DIVariable, all alike, only differing in the complex address
reference at the end.

By making the complex address into an extra argument of the
dbg.value/dbg.declare intrinsics, all of the pieces can reference the
same variable and the complex address expressions can be uniqued across
the CU, too.
Down the road, this will allow us to move other flags, such as
"indirection" out of the DIVariable, too.

The new intrinsics look like this:
declare void @llvm.dbg.declare(metadata %storage, metadata %var, metadata %expr)
declare void @llvm.dbg.value(metadata %storage, i64 %offset, metadata %var, metadata %expr)

This patch adds a new LLVM-local tag to DIExpressions, so we can detect
and pretty-print DIExpression metadata nodes.

What this patch doesn't do:

This patch does not touch the "Indirect" field in DIVariable; but moving
that into the expression would be a natural next step.

http://reviews.llvm.org/D4919
rdar://problem/17994491

Thanks to dblaikie and dexonsmith for reviewing this patch!

llvm-svn: 218778
2014-10-01 17:55:39 +00:00
David Blaikie 6cca8109ab Omit DW_AT_inline under -gmlt to save a little more space.
llvm-svn: 218719
2014-09-30 23:29:16 +00:00
David Blaikie 1cae849c04 DebugInfo: Sink the code emitting DW_AT_APPLE_omit_frame_ptr down to a more common spot.
No functional change. Pre-emptive refactoring before I start pushing
some of this subprogram creation down into DWARFCompileUnit so I can
build different subprograms in the skeleton unit from the dwo unit for
adding -gmlt-like data to the skeleton.

llvm-svn: 218713
2014-09-30 22:32:49 +00:00
David Blaikie e1c79749ca Disable the -gmlt optimization implemented in r218129 under Darwin due to issues with dsymutil.
r218129 omits DW_TAG_subprograms which have no inlined subroutines when
emitting -gmlt data. This makes -gmlt very low cost for -O0 builds.

Darwin's dsymutil reasonably considers a CU empty if it has no
subprograms (which occurs with the above optimization in -O0 programs
without any force_inline function calls) and drops the line table, CU,
and everything in this situation, making backtraces impossible.

Until dsymutil is modified to account for this, disable this
optimization on Darwin to preserve the desired functionality.
(see r218545, which should be reverted after this patch, for other
discussion/details)

Footnote:
In the long term, it doesn't look like this scheme (of simplified debug
info to describe inlining to enable backtracing) is tenable, it is far
too size inefficient for optimized code (the DW_TAG_inlined_subprograms,
even once compressed, are nearly twice as large as the line table
itself (also compressed)) and we'll be considering things like Cary's
two level line table proposal to encode all this information directly in
the line table.

llvm-svn: 218702
2014-09-30 21:28:32 +00:00
David Blaikie 3a7ce252cc Omit DW_TAG_subprograms for subprograms without inlined subroutines when producing -gmlt data
To reduce the size of -gmlt data, skip the subprograms without any
inlined subroutines. Since we've now got the ability to make these
determinations in the backend (funnily enough - we added the flag so we
wouldn't produce ranges under -gmlt, but with this change we use the
flag, but go back to producing ranges under -gmlt).

Instead, just produce CU ranges to inform the consumer which parts of
the code are described by this CU's line table. Tools could inspect the
line table directly to compute the range, but the CU ranges only seem to
be about 0.5% of object/executable size, so I'm not too worried about
teaching llvm-symbolizer that trick just yet - it's certainly a possible
piece of future work.

Update an llvm-symbolizer test just to demonstrate that this schema is
acceptable there (if it wasn't, the compiler-rt tests would catch this,
but good to have an in-llvm-tree test for llvm-symbolizer's behavior
here)

Building the clang binary with -gmlt with this patch reduces the total
size of object files by 5.1% (5.56% without ranges) without compression
and the executable by 4.37% (4.75% without ranges).

llvm-svn: 218129
2014-09-19 17:03:16 +00:00
Frederic Riss 9ba9efff56 Change DwarfCompileUnit::createGlobalVariable to getOrCreateGlobalVariable.
Summary:
This will allow to request the creation of a forward delacred variable
at is point of use (for imported declarations, this will be
DwarfDebug::constructImportedEntityDIE) rather than having to put the
forward decl in a retention list.

Note that getOrCreateGlobalVariable returns the actual definition DIE when the
routine creates a declaration and a definition DIE. If you agree this is the
right behavior, then I'll have a followup patch that registers the definition
in the DIE map instead of the declaration as it is today (this 'breaks' only
one test, where we test that the imported entity is the declaration). I'm
not sure what's best here, but it's easy enough for a consumer to follow the
DW_AT_specification link to get to the declaration, whereas it takes more
work to find the actual definition from a declaration DIE.

Reviewers: echristo, dblaikie, aprantl

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D5381

llvm-svn: 218126
2014-09-19 15:12:03 +00:00
David Blaikie 03c3dbeb62 Omit DW_AT_frame_base under -gmlt for size
llvm-svn: 218100
2014-09-19 04:55:05 +00:00
David Blaikie 6741bb09bb Remove the unused string section symbol parameter from DwarfFile::emitStrings
And since it /looked/ like the DwarfStrSectionSym was unused, I tried
removing it - but then it turned out that DwarfStringPool was
reconstructing the same label (and expecting it to have already been
emitted) and uses that.

So I kept it around, but wanted to pass it in to users - since it seemed
a bit silly for DwarfStringPool to have it passed in and returned but
itself have no use for it. The only two users don't handle strings in
both .dwo and .o files so they only ever need the one symbol - no need
to keep it (and have an unused symbol) in the DwarfStringPool used for
fission/.dwo.

Refactor a bunch of accelerator table usage to remove duplication so I
didn't have to touch 4-5 callers.

llvm-svn: 217628
2014-09-11 21:12:48 +00:00
David Blaikie d0f103775a Sink PrevCU updating into DwarfUnit::addRange to ensure consistency
So that the two operations in DwarfDebug couldn't get separated (because
I accidentally separated them in some work in progress), put them
together. While we're here, move DwarfUnit::addRange to
DwarfCompileUnit, since it's not relevant to type units.

llvm-svn: 217468
2014-09-09 23:13:01 +00:00
David Blaikie deb174fed5 Remove DwarfDebug::PrevSection, PrevCU is sufficient for handling address range holes.
PrevSection/PrevCU are used to detect holes in the address range of a CU
to ensure the DW_AT_ranges does not include those holes. When we see a
function with no debug info, though it may be in the same range as the
prior and subsequent functions, there should be a gap in the CU's
ranges. By setting PrevCU to null in that case, the range would not be
extended to cover the gap.

llvm-svn: 217466
2014-09-09 22:56:36 +00:00
David Blaikie 6a150a87ef DebugInfo: Elide lexical scopes which only contain other (inline or lexical) scopes.
DW_TAG_lexical_scopes inform debuggers about the instruction range for
which a given variable (or imported declaration/module/etc) is valid. If
the scope doesn't itself contain any such entities, it's a waste of
space and should be omitted.

We were correctly doing this for entirely empty leaves, but not for
intermediate nodes.

Reduces total (not just debug sections) .o file size for a bootstrap
-gmlt LLVM by 22% and bootstrap -gmlt clang executable by 13%. The wins
for a full -g build will be less as a % (and in absolute terms), but
should still be substantial - with some of that win being fewer
relocations, thus more substantiall reducing link times than fewer bytes
alone would have.

llvm-svn: 216861
2014-08-31 21:26:22 +00:00
David Blaikie 3fbf3b8546 DebugInfo: Move argument creation up into the caller that's unambiguously handling the subprogram scope (replacing a conditional with an assertion in the process)
llvm-svn: 216845
2014-08-31 18:04:28 +00:00
David Blaikie 2812746238 Delay adding imported entity DIEs to the lexical scope, streamlining the check for "this scope has nothing in it"
This makes the emptiness of the scope with regards to variables and
nested scopes is the same as with regards to imported entities. Just
check if we had nothing at all before we build the node.

llvm-svn: 216840
2014-08-31 05:46:17 +00:00
David Blaikie 8912df12ff Modify DwarfDebug::constructImportedEntityDIE to return rather than insert into the scope
Another step towards improving lexical_scope handling

llvm-svn: 216839
2014-08-31 05:41:15 +00:00
David Blaikie e0e8a3baa0 Refactor constructImportedEntityDIE(DwarfUnit, DIImportedEntity) to return a DIE rather than inserting it into a specified context.
First of many steps to improve lexical scope construction (to omit
trivial lexical scopes - those without any direct variables). To that
end it's easier not to create imported entities directly into the
lexical scope node, but to build them, then add them if necessary.

llvm-svn: 216838
2014-08-31 05:32:06 +00:00
David Blaikie cd4b8a2560 Simplify expression using container's front() rather than begin()->
llvm-svn: 216833
2014-08-31 02:14:26 +00:00
David Blaikie 6ba88e0f08 Revert accidentally committed patches r216787-r216789
Rushed when I realized I hadn't committed the FreeDeleter for a clang
change I'd committed, and didn't check that I had things lying around in
my client.

Apologies for the noise.

llvm-svn: 216792
2014-08-29 22:10:52 +00:00
David Blaikie 85d8bcd000 Omit dwarf::DW_AT_frame_base under -gmlt
llvm-svn: 216788
2014-08-29 22:05:27 +00:00
David Blaikie 71fffa950a Stuff
llvm-svn: 216787
2014-08-29 22:05:26 +00:00
Frederic Riss 5732301afb Use DwarfDebug::attachLowHighPC for the compilation unit DIE.
llvm-svn: 216719
2014-08-29 09:00:26 +00:00
Frederic Riss 9e32475f18 Constify MCSymbol* parameters to DwarfDebug::attachLowHighPC.
llvm-svn: 216681
2014-08-28 19:09:29 +00:00
David Blaikie c13bc97e58 Remove type unit skeletons. GDB no longer needs them & this saves a heap of space.
llvm-svn: 216521
2014-08-27 05:04:14 +00:00
David Blaikie 2f3f76fdb1 Use DILexicalBlockFile, rather than DILexicalBlock, to track discriminator changes to ensure discriminator changes don't introduce new DWARF DW_TAG_lexical_blocks.
Somewhat unnoticed in the original implementation of discriminators, but
it could cause instructions to end up in new, small,
DW_TAG_lexical_blocks due to the use of DILexicalBlock to track
discriminator changes.

Instead, use DILexicalBlockFile which we already use to track file
changes without introducing new scopes, so it works well to track
discriminator changes in the same way.

llvm-svn: 216239
2014-08-21 22:45:21 +00:00
Craig Topper 71b7b68b74 Repace SmallPtrSet with SmallPtrSetImpl in function arguments to avoid needing to mention the size.
llvm-svn: 216158
2014-08-21 05:55:13 +00:00
Craig Topper 6230691c91 Revert "Repace SmallPtrSet with SmallPtrSetImpl in function arguments to avoid needing to mention the size."
Getting a weird buildbot failure that I need to investigate.

llvm-svn: 215870
2014-08-18 00:24:38 +00:00
Craig Topper 5229cfd163 Repace SmallPtrSet with SmallPtrSetImpl in function arguments to avoid needing to mention the size.
llvm-svn: 215868
2014-08-17 23:47:00 +00:00
Adrian Prantl 5e1fa85ec6 Remove a condition that can never be true, as wittnessed by the assert
above.

llvm-svn: 215477
2014-08-12 21:55:58 +00:00
David Blaikie f73ae4fbf6 Revert "Partially revert r214761 that asserted that all concrete debug info variables had DIEs, due to a failure on Darwin."
I believe this was addressed by r215157 and r215227, so let's have
another go at the bots, etc.

This reverts commit r214880.

llvm-svn: 215412
2014-08-12 00:00:31 +00:00
Adrian Prantl 76502d8417 Add a couple of convenience accessors to DebugLocEntry::Value to further
simplify common usage patterns.

llvm-svn: 215407
2014-08-11 23:22:59 +00:00
Adrian Prantl 1c6f2ec112 Debug info: Modify DebugLocEntry::addValue to take multiple values so it
only has to sort/unique values once per batch.

llvm-svn: 215386
2014-08-11 21:06:00 +00:00
Adrian Prantl caaf053c79 Debug info: Further simplify the implementation of buildLocationList by
getting rid of the redundant DIVariable in the OpenRanges pair.

llvm-svn: 215385
2014-08-11 21:05:57 +00:00
Adrian Prantl 293dd93f95 Debug Info: Move the sorting and uniqueing of pieces from emitLocPieces()
into buildLocationList(). By keeping the list of Values sorted,
DebugLocEntry::Merge can also merge multi-piece entries.

llvm-svn: 215384
2014-08-11 21:05:55 +00:00
Adrian Prantl e09ee3faaf Debug info: Refactor DebugLocEntry's Merge function to make
buildLocationLists easier to read.

The previous implementation conflated the merging of individual pieces
and the merging of entire DebugLocEntries.

By splitting this functionality into two separate functions the intention
of the code should be clearer.

llvm-svn: 215383
2014-08-11 20:59:28 +00:00
David Blaikie bd56fbb976 DebugInfo: Recommit (reverted in r215217, originally committed in r215157) the assertion that no argument variable is overwritten by subsequent argument variables.
This turned up a bug in clang where arguments were emitted with
duplicate argument numbers (see r215227).

llvm-svn: 215228
2014-08-08 17:12:35 +00:00
David Blaikie 2b07c88668 DebugInfo: Remove assertion (added in r215157) that's firing on a blocks
test in the test-suite while I investigate further.

llvm-svn: 215217
2014-08-08 16:21:50 +00:00
David Blaikie 09fdfabdda DebugInfo: Fix overwriting/loss of inlined arguments to recursively inlined functions.
Due to an unnecessary special case, inlined arguments that happened to
be from the same function as they were inlined into were misclassified
as non-inline arguments and would overwrite the non-inlined arguments.

Assert that we never overwrite a function's arguments, and stop
misclassifying inlined arguments as non-inline arguments to fix this
issue.

Excuse the rather crappy test case - handcrafted IR might do better, or
someone who understands better how to tickle the inliner to create a
recursive inlining situation like this (though it may also be necessary
to tickle the variable in a particular way to cause it to be recorded in
the MMI side table and go down this particular path for location
information).

llvm-svn: 215157
2014-08-07 22:22:49 +00:00
David Blaikie fb0412f039 DebugInfo: Assert that any CU for which debug_loc lists are emitted, has at least one range.
This was coming in weird debug info that had variables (and hence
debug_locs) but was in GMLT mode (because it was missing the 13th field
of the compile_unit metadata) so no ranges were constructed. We should
always have at least one range for any CU with a debug_loc in it -
because the range should cover the debug_loc.

The assertion just ensures that the "!= 1" range case inside the
subsequent loop doesn't get entered for the case where there are no
ranges at all, which should never reach here in the first place.

llvm-svn: 214939
2014-08-06 00:21:25 +00:00
David Blaikie e1a26a624d DebugInfo: Move the reference to the CU from the location list entry to the list itself, since it is constant across an entire list.
This simplifies construction and usage while making the data structure
smaller. It was a holdover from the days when we didn't have a separate
DebugLocList and all we had was a flat list of DebugLocEntries.

llvm-svn: 214933
2014-08-05 23:14:16 +00:00
David Blaikie b706b58e78 Partially revert r214761 that asserted that all concrete debug info variables had DIEs, due to a failure on Darwin.
I'll work on a reduction and fix after this.

llvm-svn: 214880
2014-08-05 16:47:23 +00:00
Eric Christopher d913448b38 Remove the TargetMachine forwards for TargetSubtargetInfo based
information and update all callers. No functional change.

llvm-svn: 214781
2014-08-04 21:25:23 +00:00
David Blaikie 448c066eea Reapply "DebugInfo: Ensure that all debug location scope chains from instructions within a function, lead to the function itself."
Originally reverted in r213432 with flakey failures on an ASan self-host
build. After reduction it seems to be the same issue fixed in r213805
(ArgPromo + DebugInfo: Handle updating debug info over multiple
applications of argument promotion) and r213952 (by having
LiveDebugVariables strip dbg_value intrinsics in functions that are not
described by debug info). Though I cannot explain why this failure was
flakey...

llvm-svn: 214761
2014-08-04 19:30:08 +00:00
Adrian Prantl a6cf448226 Attempt to increase the overall happiness of the MSCV-based buildbots.
llvm-svn: 214588
2014-08-01 22:56:10 +00:00
Adrian Prantl b1416837f9 Debug info: Infrastructure to support debug locations for fragmented
variables (for example, by-value struct arguments passed in registers, or
large integer values split across several smaller registers).
On the IR level, this adds a new type of complex address operation OpPiece
to DIVariable that describes size and offset of a variable fragment.
On the DWARF emitter level, all pieces describing the same variable are
collected, sorted and emitted as DWARF expressions using the DW_OP_piece
and DW_OP_bit_piece operators.

http://reviews.llvm.org/D3373
rdar://problem/15928306

What this patch doesn't do / Future work:
- This patch only adds the backend machinery to make this work, patches
  that change SROA and SelectionDAG's type legalizer to actually create
  such debug info will follow. (http://reviews.llvm.org/D2680)
- Making the DIVariable complex expressions into an argument of dbg.value
  will reduce the memory footprint of the debug metadata.
- The sorting/uniquing of pieces should be moved into DebugLocEntry,
  to facilitate the merging of multi-piece entries.

llvm-svn: 214576
2014-08-01 22:11:58 +00:00
Manman Ren 72b07e8578 Feedback on r214189, no functionality change.
llvm-svn: 214240
2014-07-29 22:58:13 +00:00
Manman Ren f93ac4bfad [Debug Info] remove DITrivialType and use null to represent unspecified param.
Per feedback on r214111, we are going to use null to represent unspecified
parameter. If the type array is {null}, it means a function that returns void;
If the type array is {null, null}, it means a variadic function that returns
void. In summary if we have more than one element in the type array and the last
element is null, it is a variadic function.

rdar://17628609

llvm-svn: 214189
2014-07-29 18:20:39 +00:00
Manman Ren bd1628a595 [Debug Info] unique MDNodes in the enum types of each compile unit.
The enum types array by design contains pointers to MDNodes rather than DIRefs.
Unique them when handling the enum types in DwarfDebug.

rdar://17628609

llvm-svn: 214139
2014-07-28 23:04:20 +00:00
Manman Ren f8a1967c8c [Debug Info] add DISubroutineType and its creation takes DITypeArray.
DITypeArray is an array of DITypeRef, at its creation, we will create
DITypeRef (i.e use the identifier if the type node has an identifier).

This is the last patch to unique the type array of a subroutine type.

rdar://17628609

llvm-svn: 214132
2014-07-28 22:24:06 +00:00
Manman Ren ab8ffbaaee [Debug Info] rename getTypeArray to getElements, setTypeArray to setArrays.
This is the second of a series of patches to handle type uniqueing of the
type array for a subroutine type.

For vector and array types, getElements returns the array of subranges, so it
is a better name than getTypeArray. Even for class, struct and enum types,
getElements returns the members, which can be subprograms.

setArrays can set up to two arrays, the second is the templates.

This commit should have no functionality change.

llvm-svn: 214112
2014-07-28 19:14:13 +00:00
David Blaikie 29459ae83c Reapply "DebugInfo: Don't put fission type units in comdat sections."
This recommits r208930, r208933, and r208975 (by reverting r209338) and
reverts r209529 (the FIXME to readd this functionality once the tools
were fixed) now that DWP has been fixed to cope with a single section
for all fission type units.

Original commit message:

"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: 213956
2014-07-25 17:11:58 +00:00
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
Eric Christopher cfd17dd2be Revert "Reapply "DebugInfo: Ensure that all debug location scope chains from instructions within a function, lead to the function itself.""""
After a successful build it seems to have come back on a later build.

This reverts commit r213391.

llvm-svn: 213432
2014-07-18 23:57:20 +00:00
David Blaikie db5371b3bb DebugInfo: Assert that all abstract scopes are subprograms, rather than conditionalizing.
There's nothing else these should ever be...

llvm-svn: 213417
2014-07-18 22:26:59 +00:00
David Blaikie 5450240219 Reapply "DebugInfo: Ensure that all debug location scope chains from instructions within a function, lead to the function itself."""
Recommits 212776 which was reverted in r212793. This has been committed
and recommitted a few times as I try to test it harder and find/fix more
issues. The most recent revert was due to an asan bot failure which I
can't seem to reproduce locally, though I believe I'm following all the
steps the buildbot does.

So I'm going to recommit this in the hopes of investigating the failure
on the buildbot itself... apologies in advance for the bot noise. If
anyone sees failures with this /please/ provide me with any
reproductions, etc.

llvm-svn: 213391
2014-07-18 17:49:10 +00:00
Saleem Abdulrasool 271ac58eb3 CodeGen: add missing include
Found during windows unwinding work.  This header is indirectly included through
a chain leading through Support/Win64EH.h.  Explicitly include the header.  NFC.

llvm-svn: 212955
2014-07-14 16:28:09 +00:00
David Blaikie de1e1a60e8 Revert "Reapply "DebugInfo: Ensure that all debug location scope chains from instructions within a function, lead to the function itself.""
This reverts commit r212776.

Nope, still seems to be failing on the sanitizer bots... but hey, not
the msan self-host anymore, it's failing in asan now. I'll start looking
there next.

llvm-svn: 212793
2014-07-11 02:42:57 +00:00
David Blaikie 3ca92d2406 Reapply "DebugInfo: Ensure that all debug location scope chains from instructions within a function, lead to the function itself."
Committed in r212205 and reverted in r212226 due to msan self-hosting
failure, I believe I've got that fixed by r212761 to Clang.

Original commit message:

"Originally committed in r211723, reverted in r211724 due to failure
cases found and fixed (ArgumentPromotion: r211872, Inlining: r212065),
committed again in r212085 and reverted again in r212089 after fixing
some other cases, such as debug info subprogram lists not keeping track
of the function they represent (r212128) and then short-circuiting
things like LiveDebugVariables that build LexicalScopes for functions
that might not have full debug info.

And again, I believe the invariant actually holds for some reasonable
amount of code (but I'll keep an eye on the buildbots and see what
happens... ).

Original commit message:

PR20038: DebugInfo: Inlined call sites where the caller has debug info
but the call itself has no debug location.

This situation does bad things when inlined, so I've fixed Clang not to
produce inlinable call sites without locations when the caller has debug
info (in the one case where I could find that this occurred). This
updates the PR20038 test case to be what clang now produces, and readds
the assertion that had to be removed due to this bug.

I've also beefed up the debug info verifier to help diagnose these
issues in the future, and I hope to add checks to the inliner to just
assert-fail if it encounters this situation. If, in the future, we
decide we have to cope with this situation, the right thing to do is
probably to just remove all the DebugLocs from the inlined
instructions."

llvm-svn: 212776
2014-07-10 22:59:39 +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 9a0f7948a2 Revert "DebugInfo: Ensure that all debug location scope chains from instructions within a function, lead to the function itself."
This reverts commit r212205.

Reverting this again, still seeing crashes when building compiler-rt...
Sorry for the continued noise, not sure why I'm failing to reproduce
this locally.

llvm-svn: 212226
2014-07-02 21:42:28 +00:00
David Blaikie 9408f5282e DebugInfo: Ensure that all debug location scope chains from instructions within a function, lead to the function itself.
Originally committed in r211723, reverted in r211724 due to failure
cases found and fixed (ArgumentPromotion: r211872, Inlining: r212065),
committed again in r212085 and reverted again in r212089 after fixing
some other cases, such as debug info subprogram lists not keeping track
of the function they represent (r212128) and then short-circuiting
things like LiveDebugVariables that build LexicalScopes for functions
that might not have full debug info.

And again, I believe the invariant actually holds for some reasonable
amount of code (but I'll keep an eye on the buildbots and see what
happens... ).

Original commit message:

PR20038: DebugInfo: Inlined call sites where the caller has debug info
but the call itself has no debug location.

This situation does bad things when inlined, so I've fixed Clang not to
produce inlinable call sites without locations when the caller has debug
info (in the one case where I could find that this occurred). This
updates the PR20038 test case to be what clang now produces, and readds
the assertion that had to be removed due to this bug.

I've also beefed up the debug info verifier to help diagnose these
issues in the future, and I hope to add checks to the inliner to just
assert-fail if it encounters this situation. If, in the future, we
decide we have to cope with this situation, the right thing to do is
probably to just remove all the DebugLocs from the inlined instructions.

llvm-svn: 212205
2014-07-02 18:32:05 +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