Commit Graph

3684 Commits

Author SHA1 Message Date
Zachary Turner af299ea5d4 [PDB] General improvements to Stream library.
This adds various new functionality and cleanup surrounding the
use of the Stream library.  Major changes include:

* Renaming of all classes for more consistency / meaningfulness
* Addition of some new methods for reading multiple values at once.
* Full suite of unit tests for reader / writer functionality.
* Full set of doxygen comments for all classes.
* Streams now store their own endianness.
* Fixed some bugs in a few of the classes that were discovered
  by the unit tests.

llvm-svn: 296215
2017-02-25 00:44:30 +00:00
Zachary Turner d2684b7969 [PDB] Rename Stream related source files.
This is part of a larger effort to get the Stream code moved
up to Support.  I don't want to do it in one large patch, in
part because the changes are so big that it will treat everything
as file deletions and add, losing history in the process.
Aside from that though, it's just a good idea in general to
make small changes.

So this change only changes the names of the Stream related
source files, and applies necessary source fix ups.

llvm-svn: 296211
2017-02-25 00:33:34 +00:00
Justin Bogner 369ba753aa OptDiag: Summarize the instruction count in asm-printer
Add an optimization remark to asm-printer that summarizes the number
of instructions emitted per function.

llvm-svn: 296053
2017-02-24 00:19:22 +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
Eugene Zelenko d96089b248 [MC] Fix some Clang-tidy modernize and Include What You Use warnings; other minor fixes (NFC).
Same changes in files affected by reduced MC headers dependencies.

llvm-svn: 295009
2017-02-14 00:33:36 +00:00
Sanne Wouda 91eadad3bd [Assembler] Improve diagnostics for inline assembly.
Summary:
Keep a vector of LocInfos around; one for each call to EmitInlineAsm.
Since each call to EmitInlineAsm creates a new buffer in the inline asm
SourceMgr, we can use the buffer number to map to the right LocInfo.

Reviewers: rengolin, grosbach, rnk, echristo

Reviewed By: rnk

Subscribers: mehdi_amini, llvm-commits

Differential Revision: https://reviews.llvm.org/D29769

llvm-svn: 294947
2017-02-13 13:58:00 +00:00
Simon Dardis 2e8cdbd795 [DebugInfo] Rename EmitDebugValue to EmitDebugThreadLocal (NFC)
As pointed out by David Blaikie in the post commit review of
r292624, EmitDebugValue should be called EmitDebugThreadLocal.

llvm-svn: 294500
2017-02-08 19:03:46 +00:00
Sanne Wouda 2933875cc2 [Assembler] Enable nicer diagnostics for inline assembly.
Fixed test.

Summary:
Enables source location in diagnostic messages from the backend.  This
is after parsing, during finalization.  This requires the SourceMgr, the
inline assembly string buffer, and DiagInfo to still be alive after
EmitInlineAsm returns.

This patch creates a single SourceMgr for inline assembly inside the
AsmPrinter.  MCContext gets a pointer to this SourceMgr.  Using one
SourceMgr per call to EmitInlineAsm would make it difficult for
MCContext to figure out in which SourceMgr the SMLoc is located, while a
single SourceMgr can figure it out if it has multiple buffers.

The Str argument to EmitInlineAsm is copied into a buffer and owned by
the inline asm SourceMgr.  This ensures that DiagHandlers won't print
garbage.  (Clang emits a "note: instantiated into assembly here", which
refers to this string.)

The AsmParser gets destroyed before finalization, which means that the
DiagHandlers the AsmParser installs into the SourceMgr will be stale.
Restore the saved DiagHandlers.

Since now we're using just one SourceMgr for multiple inline asm
strings, we need to tell the AsmParser which buffer it needs to parse
currently.  Hand a buffer id -- returned from SourceMgr::
AddNewSourceBuffer -- to the AsmParser.

Reviewers: rnk, grosbach, compnerd, rengolin, rovka, anemet

Reviewed By: rnk

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D29441
    

llvm-svn: 294458
2017-02-08 14:48:05 +00:00
Diana Picus 79add417b4 Revert "[Assembler] Enable nicer diagnostics for inline assembly."
This reverts commit r294433 because it seems it broke the buildbots.

llvm-svn: 294448
2017-02-08 14:02:16 +00:00
Sanne Wouda 09adc245ea [Assembler] Enable nicer diagnostics for inline assembly.
Summary:
Enables source location in diagnostic messages from the backend.  This
is after parsing, during finalization.  This requires the SourceMgr, the
inline assembly string buffer, and DiagInfo to still be alive after
EmitInlineAsm returns.

This patch creates a single SourceMgr for inline assembly inside the
AsmPrinter.  MCContext gets a pointer to this SourceMgr.  Using one
SourceMgr per call to EmitInlineAsm would make it difficult for
MCContext to figure out in which SourceMgr the SMLoc is located, while a
single SourceMgr can figure it out if it has multiple buffers.

The Str argument to EmitInlineAsm is copied into a buffer and owned by
the inline asm SourceMgr.  This ensures that DiagHandlers won't print
garbage.  (Clang emits a "note: instantiated into assembly here", which
refers to this string.)

The AsmParser gets destroyed before finalization, which means that the
DiagHandlers the AsmParser installs into the SourceMgr will be stale.
Restore the saved DiagHandlers.

Since now we're using just one SourceMgr for multiple inline asm
strings, we need to tell the AsmParser which buffer it needs to parse
currently.  Hand a buffer id -- returned from SourceMgr::
AddNewSourceBuffer -- to the AsmParser.

Reviewers: rnk, grosbach, compnerd, rengolin, rovka, anemet

Reviewed By: rnk

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D29441

llvm-svn: 294433
2017-02-08 10:20:07 +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
Matthias Braun 194ded551c Use print() instead of dump() in code
llvm-svn: 293371
2017-01-28 06:53:55 +00:00
Matthias Braun 8c209aa877 Cleanup dump() functions.
We had various variants of defining dump() functions in LLVM. Normalize
them (this should just consistently implement the things discussed in
http://lists.llvm.org/pipermail/cfe-dev/2014-January/034323.html

For reference:
- Public headers should just declare the dump() method but not use
  LLVM_DUMP_METHOD or #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
- The definition of a dump method should look like this:
  #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
  LLVM_DUMP_METHOD void MyClass::dump() {
    // print stuff to dbgs()...
  }
  #endif

llvm-svn: 293359
2017-01-28 02:02:38 +00:00
Tim Northover 5d27063eb4 DebugInfo: remove unused parameter from function. NFC.
I think it's a hold-over from some previous iteration, but it's never
set to true in LLVM as it exists now.

llvm-svn: 293086
2017-01-25 20:58:07 +00:00
Petar Jovanovic dbb39356b4 [mips] Fix debug information for __thread variable
This patch fixes debug information for __thread variable on Mips
using .dtprelword and .dtpreldword directives.

Patch by Aleksandar Beserminji.

Differential Revision: http://reviews.llvm.org/D28770

llvm-svn: 292624
2017-01-20 17:53:30 +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
Teresa Johnson 2d384ac381 Don't create a comdat group for a dropped def with initializer
Non-prevailing weak/linkonce odr symbols will be dropped by ThinLTO to
available_externally when possible. If they had an initializer in the
global_ctors list, a comdat group was being created. This code
already had logic to skip available_externally defs, but now the
EliminateAvailableExternally pass will drop these symbols to
declarations earlier. Change the check to skip all declarations for
linker (which includes available_externally along with declarations).

Reviewers: mehdi_amini

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D28737

llvm-svn: 292408
2017-01-18 16:58:43 +00:00
Zachary Turner 629cb7d8cc [CodeView] Finish decoupling TypeDatabase from TypeDumper.
Previously the type dumper itself was passed around to a lot of different
places and manipulated in ways that were more appropriate on the type
database. For example, the entire TypeDumper was passed into the symbol
dumper, when all the symbol dumper wanted to do was lookup the name of a
TypeIndex so it could print it. That's what the TypeDatabase is for --
mapping type indices to names.

Another example is how if the user runs llvm-pdbdump with the option to
dump symbols but not types, we still have to visit all types so that we
can print minimal information about the type of a symbol, but just without
dumping full symbol records. The way we did this before is by hacking it
up so that we run everything through the type dumper with a null printer,
so that the output goes to /dev/null. But really, we don't need to dump
anything, all we want to do is build the type database. Since
TypeDatabaseVisitor now exists independently of TypeDumper, we can do
this. We just build a custom visitor callback pipeline that includes a
database visitor but not a dumper.

All the hackery around printers etc goes away. After this patch, we could
probably even delete the entire CVTypeDumper class since really all it is
at this point is a thin wrapper that hides the details of how to build a
useful visitation pipeline. It's not a priority though, so CVTypeDumper
remains for now.

After this patch we will be able to easily plug in a different style of
type dumper by only implementing the proper visitation methods to dump
one-line output and then sticking it on the pipeline.

Differential Revision: https://reviews.llvm.org/D28524

llvm-svn: 291724
2017-01-11 23:24:22 +00:00
Zachary Turner a9054ddd9c [CodeView/PDB] Rename a bunch of files.
We were starting to get some name clashes between llvm-pdbdump
and the common CodeView framework, so I took this opportunity
to rename a bunch of files to more accurately describe their
usage.  This also helps in llvm-pdbdump to distinguish
between different files and whether they are used for pretty
dump mode or raw dump mode.

llvm-svn: 291627
2017-01-11 00:35:43 +00:00
Zachary Turner c640b76db5 [CodeView] Add TypeDatabase class.
This creates a centralized class in which to store type records.
It stores types as an array of entries, which matches the
notion of a type stream being a topologically sorted DAG.
Logic to build up such a database was already being used in
CVTypeDumper, so CVTypeDumper is now updated to to read from
a TypeDatabase which is filled out by an earlier visitor in
the pipeline.

Differential Revision: https://reviews.llvm.org/D28486

llvm-svn: 291626
2017-01-11 00:35:08 +00:00
Victor Leschuk cbddae74f5 DebugInfo: support for DW_FORM_implicit_const
Support for DW_FORM_implicit_const DWARFv5 feature.
When this form is used attribute value goes to .debug_abbrev section (as SLEB).
As this form would break any debug tool which doesn't support DWARFv5
it is guarded by dwarf version check. Attempt to use this form with
dwarf version <= 4 is considered a fatal error.

Differential Revision: https://reviews.llvm.org/D28456

llvm-svn: 291599
2017-01-10 21:18:26 +00:00
Joerg Sonnenberger 83963995c6 PR 31534: When emitting both DWARF unwind tables and debug information,
do not use .cfi_sections. This requires checking if any non-declaration
function in the module needs an unwind table.

llvm-svn: 291172
2017-01-05 20:55:28 +00:00
Saleem Abdulrasool 6252bd8eac MC: support passing search paths to the IAS
This is needed to support inclusion in inline assembly via the
`.include` directive.

llvm-svn: 291085
2017-01-05 05:56:39 +00:00
Dean Michael Berris f7e7b938ea [XRay] Merge instrumentation point table emission code into AsmPrinter.
Summary:
No need to have this per-architecture.  While there, unify 32-bit ARM's
behaviour with what changed elsewhere and start function names lowercase
as per the coding standards.  Individual entry emission code goes to the
entry's own class.

Fully tested on amd64, cross-builds on both ARMs and PowerPC.

Reviewers: dberris

Subscribers: aemerson, llvm-commits

Differential Revision: https://reviews.llvm.org/D28209

llvm-svn: 290858
2017-01-03 04:30:21 +00:00
Joerg Sonnenberger 7b83732a40 Emit .cfi_sections before the first .cfi_startproc
GNU as rejects input where .cfi_sections is used after .cfi_startproc,
if the new section differs from the old. Adjust our output to always
emit .cfi_sections before the first .cfi_startproc to minimize necessary
code.

Differential Revision: https://reviews.llvm.org/D28011

llvm-svn: 290817
2017-01-02 18:05:27 +00:00
Keno Fischer f7d84ee6ff Reapply "[CodeGen] Fix invalid DWARF info on Win64"
This reapplies rL289013 (reverted in rL289014) with the fixes identified
in D21731. Should hopefully pass the buildbots this time.

llvm-svn: 290809
2017-01-02 03:00:19 +00:00
Reid Kleckner 92647369fc [WinEH] Don't assume endFunction is called while in .text
Jump table emission can switch to .rdata before
WinException::endFunction gets called. Just remember the appropriate
text section we started in and reset back to it when we end the
function. We were already switching sections back from .xdata anyway.

Fixes the first problem in PR31488, so that now COFF switch tables can
live in .rdata if we want them to.

llvm-svn: 290678
2016-12-28 19:05:12 +00:00
Adrian Prantl 5542da4bbc Fix an assertion in DwarfExpression when emitting fragments in vector registers
When DwarfExpression is emitting a fragment that is located in a
register and that fragment is smaller than the register, and the
register must be composed from sub-registers (are you still with me?)
the last DW_OP_piece operation must not be larger than the size of the
fragment itself, since the last piece of the fragment could be smaller
than the last subregister that is being emitted.

rdar://problem/29779065

llvm-svn: 290324
2016-12-22 06:10:41 +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
Zachary Turner 46225b193f Resubmit "[CodeView] Hook CodeViewRecordIO for reading/writing symbols."
The original patch was broken due to some undefined behavior
as well as warnings that were triggering -Werror.

llvm-svn: 290000
2016-12-16 22:48:14 +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
Zachary Turner d0fffd1d14 Revert "[CodeView] Hook CodeViewRecordIO for reading/writing symbols."
This reverts commit r289978, which is failing due to some rebase/merge
issues.

llvm-svn: 289981
2016-12-16 19:25:23 +00:00
Zachary Turner a4e7dfbc16 [CodeView] Hook CodeViewRecordIO for reading/writing symbols.
This is the 3rd of 3 patches to get reading and writing of
CodeView symbol and type records to use a single codepath.

Differential Revision: https://reviews.llvm.org/D26427

llvm-svn: 289978
2016-12-16 19:20:35 +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
Stephan Bergmann 17c7f70362 Replace APFloatBase static fltSemantics data members with getter functions
At least the plugin used by the LibreOffice build
(<https://wiki.documentfoundation.org/Development/Clang_plugins>) indirectly
uses those members (through inline functions in LLVM/Clang include files in turn
using them), but they are not exported by utils/extract_symbols.py on Windows,
and accessing data across DLL/EXE boundaries on Windows is generally
problematic.

Differential Revision: https://reviews.llvm.org/D26671

llvm-svn: 289647
2016-12-14 11:57:17 +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