Commit Graph

2582 Commits

Author SHA1 Message Date
Reid Kleckner 2bcb288ade [codeview] Let the X86 backend tell us the VFRAME offset adjustment
Use MachineFrameInfo's OffsetAdjustment field to pass this information
from the target to CodeViewDebug.cpp. The X86 backend doesn't use it for
any other purpose.

This fixes PR38857 in the case where there is a non-aligned quantity of
CSRs and a non-aligned quantity of locals.

llvm-svn: 346062
2018-11-03 00:41:52 +00:00
Wolfgang Pieb 5253cccbd5 [DWARF v5] Verifier: Add checks for DW_FORM_strx* forms.
Adding functionality to the DWARF verifier for DWARF v5 strx* forms which 
index into the string offsets table.

Differential Revision: https://reviews.llvm.org/D54049

llvm-svn: 346061
2018-11-03 00:27:35 +00:00
Fangrui Song 999570a2f4 [DWARF] Fix typo, .gnu_index -> .gdb_index
llvm-svn: 346039
2018-11-02 20:34:40 +00:00
Alexey Bataev 8831ef7a16 [DEBUGINFO, NVPTX]DO not emit ',debug' option if no debug info or only debug directives are requested.
Summary:
If the output of debug directives only is requested, we should drop
emission of ',debug' option from the target directive. Required for
supporting of nvprof profiler.

Reviewers: probinson, echristo, dblaikie

Subscribers: Hahnfeld, jholewinski, llvm-commits, JDevlieghere, aprantl

Differential Revision: https://reviews.llvm.org/D46061

llvm-svn: 345972
2018-11-02 13:47:47 +00:00
Matthias Braun fdddd8e734 test/DebugInfo: Convert some tests to MIR
These tests are meant to test dwarf emission (or prolog/epilogue
generation) so we can convert them to .mir and only run the relevant
part of the pipeline.
This way they become independent of changes in earlier passes such as my
planned changes to RegAllocFast.

llvm-svn: 345919
2018-11-02 01:31:52 +00:00
Zachary Turner 56a5a0c3ce [CodeView] Emit the correct TypeIndex for std::nullptr_t.
The TypeIndex used by cl.exe is 0x103, which indicates a SimpleTypeMode
of NearPointer (note the absence of the bitness, normally pointers use a
mode of NearPointer32 or NearPointer64) and a SimpleTypeKind of void.
So this is basically a void*, but without a specified size, which makes
sense given how std::nullptr_t is defined.

clang-cl was actually not emitting *anything* for this. Instead, when we
encountered std::nullptr_t in a DIType, we would actually just emit a
TypeIndex of 0, which is obviously wrong.

std::nullptr_t in DWARF is represented as a DW_TAG_unspecified_type with
a name of "decltype(nullptr)", so we add that logic along with a test,
as well as an update to the dumping code so that we no longer print
void* when dumping 0x103 (which would previously treat Void/NearPointer
no differently than Void/NearPointer64).

Differential Revision: https://reviews.llvm.org/D53957

llvm-svn: 345811
2018-11-01 04:02:41 +00:00
Matthias Braun a83403892a MachineOperand/MIParser: Do not print debug-use flag, infer it
The debug-use flag must be set exactly for uses on DBG_VALUEs.  This is
so obvious that it can be trivially inferred while parsing. This will
reduce noise when printing while omitting an information that has little
value to the user.

The parser will keep recognizing the flag for compatibility with old
`.mir` files.

Differential Revision: https://reviews.llvm.org/D53903

llvm-svn: 345671
2018-10-30 23:28:27 +00:00
Francis Visoiu Mistrih 0e237d357e [X86] Re-enable the machine verifier after fixing more tests
Was disabled again in r345528. Hopefully this the bots.

llvm-svn: 345593
2018-10-30 12:20:17 +00:00
Matthias Braun c045c557b0 Relax fast register allocator related test cases; NFC
- Relex hard coded registers and stack frame sizes
- Some test cleanups
- Change phi-dbg.ll to match on mir output after phi elimination instead
  of going through the whole codegen pipeline.

This is in preparation for https://reviews.llvm.org/D52010
I'm committing all the test changes upfront that work before and after
independently.

llvm-svn: 345532
2018-10-29 20:10:42 +00:00
Francis Visoiu Mistrih 61c9de7565 [X86] Enable the MachineVerifier by default
The machine verifier was disabled for x86 by default. There are now only
9 tests failing, compared to what previously was between 20 and 30.

This is a good opportunity to file bugs for all the remaining issues,
then explicitly disable the failing tests and enabling the machine
verifier by default.

This allows us to avoid adding new tests that break the verifier.

PR27481

llvm-svn: 345513
2018-10-29 16:57:43 +00:00
David Blaikie 2f9c42c994 llvm-dwarfdump: loclists: Don't expect an (albeit empty) expression for LLE_base_address
llvm-svn: 345320
2018-10-25 21:35:59 +00:00
Alexey Bataev 0f2fe4f135 [DEBUG_INFO][NVPTX]Fix processing of DBG_VALUES.
Summary:
If the instruction in the eliminateFrameIndex function is a DBG_VALUE
instruction, it requires special processing. The frame register is set
to VRFrame and the offset is based on the object offset.
The code is similar to the code used in
lib/CodeGen/PrologEpilogInserter.cpp.

Reviewers: tra

Subscribers: jholewinski, llvm-commits

Differential Revision: https://reviews.llvm.org/D53657

llvm-svn: 345269
2018-10-25 14:27:27 +00:00
David Blaikie 60fddac907 DebugInfo: Reuse common addresses for rnglist base address selections
This makes the offsets larger (since they are further from the base
address) but those are in the .dwo - and allows removing addresses and
relocations from the .o file.

This could be built into the AddressPool more fundamentally, perhaps -
when you ask for an AddressPool entry you could say "or give me some
other entry and an offset I need to use" - though what to do about
situations where the first use of an address in a section is not the
earliest address in that section... is tricky.

At least with range addresses we can be fairly sure we've seen the
earliest address first because we see the start address for the
function.

llvm-svn: 345224
2018-10-24 23:36:29 +00:00
David Blaikie c8ae096739 llvm-dwarfdump: Account for skeleton addr_base when dumping addresses in split unit in the same file
llvm-svn: 345215
2018-10-24 22:44:54 +00:00
Alexey Bataev c15c853c3a [DEBUGINFO, NVPTX] Try to pack bytes data into a single string.
Summary:
If the target does not support `.asciz` and `.ascii` directives, the
strings are represented as bytes and each byte is placed on the new line
as a separate byte directive `.b8 <data>`. NVPTX target allows to
represent the vector of the data of the same type as a vector, where
values are separated using `,` symbol: `.b8 <data1>,<data2>,...`. This
allows to reduce the size of the final PTX file. Ptxas tool includes ptx
files into the resulting binary object, so reducing the size of the PTX
file is important.

Reviewers: tra, jlebar, echristo

Subscribers: jholewinski, llvm-commits

Differential Revision: https://reviews.llvm.org/D45822

llvm-svn: 345142
2018-10-24 14:04:00 +00:00
George Rimar 209232091c [llvm-dwarfdump] - Fix win10 build bot failture.
Bot failed: 
http://lab.llvm.org:8011/builders/llvm-clang-lld-x86_64-scei-ps4-windows10pro-fast/builds/20877/steps/test/logs/stdio

This was broken after the 
r344895 "[llvm-dwarfdump] - Add the support of parsing .debug_loclists."
because of wrong formatting specifiers used.

llvm-svn: 344896
2018-10-22 12:18:30 +00:00
George Rimar 4c7dd9cf0a [llvm-dwarfdump] - Add the support of parsing .debug_loclists.
This teaches llvm-dwarfdump to dump the content of .debug_loclists sections.

It converts the DWARFDebugLocDWO class to DWARFDebugLoclists,
teaches llvm-dwarfdump about .debug_loclists section and
adds the implementation for parsing the DW_LLE_offset_pair entries.

Differential revision: https://reviews.llvm.org/D53364

llvm-svn: 344895
2018-10-22 11:30:54 +00:00
David Blaikie 14cfa0dcdc DebugInfo: Use base address specifiers more aggressively
Using a base address specifier even for a single-element range is a size
win for object files (7 words versus 8 words - more significant savings
if the debug info is compressed (since it's 3 words of uncompressable
reloc + 4 compressable words compared to 6 uncompressable reloc + 2
compressable words) - does trade off executable size increase though.

llvm-svn: 344841
2018-10-20 09:16:49 +00:00
David Blaikie 2df23a4e2e DebugInfo: Use DW_OP_addrx in DWARFv5
Reuse addresses in the address pool, even in non-split cases.

llvm-svn: 344838
2018-10-20 08:54:05 +00:00
David Blaikie 32e09de91c DebugInfo: Implement debug_rnglists.dwo
Save space/relocations in .o files by keeping dwo ranges in the dwo
file rather than the .o file.

llvm-svn: 344837
2018-10-20 08:12:36 +00:00
David Blaikie c4af8bf29f DebugInfo: Use address pool forms in debug_rnglists
Save no relocations by reusing addresses from the address pool.

llvm-svn: 344836
2018-10-20 07:36:39 +00:00
David Blaikie 161dd3c186 DebugInfo: Use debug_addr for non-dwo addresses in DWARF 5
Putting addresses in the address pool, even with non-fission, can reduce
relocations - reusing the addresses from debug_info and debug_rnglists
(the latter coming soon)

llvm-svn: 344834
2018-10-20 06:02:15 +00:00
Wolfgang Pieb 6214c11cb7 [DWARF] Make llvm-dwarfdump display location lists in a .dwp file correctly. Fixes PR38990.
Considers the index when extracting location lists from a .dwp file.
Majority of the patch by David Blaikie.

Reviewers: dblaikie

Differential revision: https://reviews.llvm.org/D53155

llvm-svn: 344807
2018-10-19 19:23:16 +00:00
Jonas Devlieghere 344cac5efd [dwarfdump] Hide ranges in diff-mode.
llvm-dwarfdump --diff should not print DW_AT_ranges. This patch fixes
that.

Differential revision: https://reviews.llvm.org/D53353

llvm-svn: 344794
2018-10-19 17:57:53 +00:00
Aleksandar Beserminji 81eb440772 [mips][micromips] Fix overlaping FDEs error
When compiling static executable for micromips, CFI symbols
are incorrectly labeled as MICROMIPS, which cause
".eh_frame_hdr refers to overlapping FDEs." error.

This patch does not label CFI symbols as MICROMIPS, and FDEs do not
overlap anymore. This patch also exposes another bug, which is fixed
here: https://reviews.llvm.org/D52985

Differential Revision: https://reviews.llvm.org/D52987

llvm-svn: 344516
2018-10-15 14:39:12 +00:00
Aleksandar Beserminji 585f55bb8b [mips][micromips] Revert "Fix overlaping FDEs error"
This reverts r344511.

llvm-svn: 344515
2018-10-15 14:36:48 +00:00
Aleksandar Beserminji 10ec5c8c28 [mips][micromips] Fix overlaping FDEs error
When compiling static executable for micromips, CFI symbols
are incorrectly labeled as MICROMIPS, which cause
".eh_frame_hdr refers to overlapping FDEs." error.

This patch does not label CFI symbols as MICROMIPS, and FDEs do not
overlap anymore. This patch also exposes another bug, which is fixed
here: https://reviews.llvm.org/D52985

Differential Revision: https://reviews.llvm.org/D52987

llvm-svn: 344511
2018-10-15 12:59:17 +00:00
Reid Kleckner 810687cb57 [codeview] Emit S_BUILDINFO and LF_BUILDINFO with cwd and source file
Summary: We can fill in the command line and compiler path later if we want.

Reviewers: zturner

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D53179

llvm-svn: 344393
2018-10-12 18:19:06 +00:00
Matthias Braun c7efb6f990 Revert "DwarfDebug: Pick next location in case of missing location at block begin"
It originally triggered a stepping problem in the debugger, which could
be fixed by adjusting CodeGen/LexicalScopes.cpp however it seems we prefer
the previous behavior anyway.

See the discussion for details: http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20181008/593833.html

This reverts commit r343880.
This reverts commit r343874.

llvm-svn: 344318
2018-10-11 23:37:58 +00:00
Zachary Turner 5989281cf3 [PDB] Fix another bug in globals stream name lookup.
When we're on the last bucket the computation is tricky.
We were failing when the last bucket contained multiple
matches.  Added a new test for this.

llvm-svn: 344081
2018-10-09 21:19:03 +00:00
Zachary Turner c8207fa59b [PDB] fix a bug in global stream name lookup.
When we're looking up a record in the last hash bucket chain, we
need to be careful with the end-offset calculation.

llvm-svn: 344001
2018-10-08 22:38:27 +00:00
Petar Jovanovic e2877ad3b9 [DebugInfo] Fix debug information label tests
Remove the space in the asm check so that the expression is more general
and can also capture MIPS labels which can be surrounded by braces, e.g.:

.4byte        ($tmp1)                 # DW_AT_low_pc

Also change optimization level to O0 because the DW_TAG_label does not
appear on MIPS when -O2 is used.

Patch by Milos Stojanovic.

Differential Revision: https://reviews.llvm.org/D52901

llvm-svn: 343999
2018-10-08 22:10:34 +00:00
Zachary Turner affaff8b60 Don't use back-quotes in a run line.
This works on Windows, but seems to be breaking tests that
use an external shell (e.g. bash) because backquote has special
meaning.

This particular argument wasn't crucial for the test, so I've
just removed it.

llvm-svn: 343971
2018-10-08 15:14:05 +00:00
Zachary Turner 94926a6db8 [PDB] Add the ability to lookup global symbols by name.
The Globals table is a hash table keyed on symbol name, so
it's possible to lookup symbols by name in O(1) time.  Add
a function to the globals stream to do this, and add an option
to llvm-pdbutil to exercise this, then use it to write some
tests to verify correctness.

llvm-svn: 343951
2018-10-08 04:19:16 +00:00
Matthias Braun 81578e9f77 X86, AArch64, ARM: Do not attach debug location to spill/reload instructions
This rebases and recommits r343520. hwasan should be fixed now and this
shouldn't break the tests anymore.

Spill/reload instructions are artificially generated by the compiler and
have no relation to the original source code. So the best thing to do is
not attach any debug location to them (instead of just taking the next
debug location we find on following instructions).

Differential Revision: https://reviews.llvm.org/D52125

llvm-svn: 343895
2018-10-05 22:00:13 +00:00
Vedant Kumar 0fea2f5c00 Specify -mtriple=x86_64 in an X86-specific dwarf test
On the PPC bot, the %llc_dwarf substitution does not contain an -mtriple
argument. This can cause the wrong backend to be exercised.

This causes issues because the backends differ in when they decide to
emit tail calls:

  http://lab.llvm.org:8011/builders/clang-ppc64be-linux-multistage/builds/12440

This is mostly a speculative fix as I don't have a PPC machine to test
with.

llvm-svn: 343893
2018-10-05 21:54:58 +00:00
Vedant Kumar 8c46668b6e [LiveDebugValues] Extend var ranges through artificial blocks
ASan often introduces basic blocks consisting exclusively of
instructions without debug locations, or with line 0 debug locations.

LiveDebugValues needs to extend variable ranges through these artificial
blocks. Otherwise, a lot of variables disappear -- even at -O0.

Typically, LiveDebugValues does not extend a variable's range into a
block unless the block is essentially "part of" the variable's scope
(for a precise definition, see LexicalScopes::dominates). This patch
relaxes the lexical dominance check for artificial blocks.

This makes the following Swift program debuggable at -O0:
```
  1| var x = 100
  2| print("x = \(x)")
```

rdar://39127144

Differential Revision: https://reviews.llvm.org/D52921

llvm-svn: 343890
2018-10-05 21:44:15 +00:00
Vedant Kumar c5a0cb846d Disable the dwarf callsite attrs test on Windows
The Windows formats don't understand relocations inside of AT_return_pc.

  http://lab.llvm.org:8011/builders/clang-x64-windows-msvc/builds/270

llvm-svn: 343888
2018-10-05 21:28:14 +00:00
Vedant Kumar 25905398e5 Avoid hardcoding PC addresses in a dwarf test
The PCs appear to vary from builder-to-builder:

  http://lab.llvm.org:8011/builders/clang-ppc64be-linux-lnt/builds/20053

llvm-svn: 343886
2018-10-05 21:05:31 +00:00
Vedant Kumar 5931b4e5b5 [DebugInfo] Add support for DWARF5 call site-related attributes
DWARF v5 introduces DW_AT_call_all_calls, a subprogram attribute which
indicates that all calls (both regular and tail) within the subprogram
have call site entries. The information within these call site entries
can be used by a debugger to populate backtraces with synthetic tail
call frames.

Tail calling frames go missing in backtraces because the frame of the
caller is reused by the callee. Call site entries allow a debugger to
reconstruct a sequence of (tail) calls which led from one function to
another. This improves backtrace quality. There are limitations: tail
recursion isn't handled, variables within synthetic frames may not
survive to be inspected, etc. This approach is not novel, see:

  https://gcc.gnu.org/wiki/summit2010?action=AttachFile&do=get&target=jelinek.pdf

This patch adds an IR-level flag (DIFlagAllCallsDescribed) which lowers
to DW_AT_call_all_calls. It adds the minimal amount of DWARF generation
support needed to emit standards-compliant call site entries. For easier
deployment, when the debugger tuning is LLDB, the DWARF requirement is
adjusted to v4.

Testing: Apart from check-{llvm, clang}, I built a stage2 RelWithDebInfo
clang binary. Its dSYM passed verification and grew by 1.4% compared to
the baseline. 151,879 call site entries were added.

rdar://42001377

Differential Revision: https://reviews.llvm.org/D49887

llvm-svn: 343883
2018-10-05 20:37:17 +00:00
Reid Kleckner 0cb905142a Fix dwarf-no-source-loc.ll path separator on Windows
llvm-svn: 343880
2018-10-05 19:46:51 +00:00
Matthias Braun fb43114ba2 DwarfDebug: Pick next location in case of missing location at block begin
Context: Compiler generated instructions do not have a debug location
assigned to them. However emitting 0-line records for all of them bloats
the line tables for very little benefit so we usually avoid doing that.

Not emitting anything will lead to the previous debug location getting
applied to the locationless instructions. This is not desirable for
block begin and after labels. Previously we would emit simply emit
line-0 records in this case, this patch changes the behavior to do a
forward search for a debug location in these cases before emitting a
line-0 record to further reduce line table bloat.

Inspired by the discussion in https://reviews.llvm.org/D52862

llvm-svn: 343874
2018-10-05 18:29:24 +00:00
Matthew Voss f8ab35a4f4 Emit template type and value parameter DIEs for template variables.
Summary:
Ensure the TemplateParam attribute of the DIGlobalVariable node is translated into the proper DIEs.

Resolves https://bugs.llvm.org/show_bug.cgi?id=22119

Reviewers: dblaikie, probinson, aprantl, JDevlieghere, clayborg, whitequark, deadalnix

Reviewed By: dblaikie

Subscribers: llvm-commits

Tags: #debug-info

Differential Revision: https://reviews.llvm.org/D52057

llvm-svn: 343706
2018-10-03 18:44:53 +00:00
Reid Kleckner 9c0baa524c Relax dbg-declare-inalloca.ll test more
We don't need to match the precise type index number here. It's not
important. The type name is what matters to make this test useful.

llvm-svn: 343642
2018-10-02 22:28:10 +00:00
Fangrui Song e5652fc682 [CodeView] Try fixing DebugInfo/X86/dbg-declare-inalloca.ll
llvm-svn: 343639
2018-10-02 22:03:31 +00:00
Aaron Smith da0602c154 [CodeView] Only add the Scoped flag for an enum type when it has an immediate function scope to match MSVC
Reviewers: rnk, zturner, llvm-commits

Reviewed By: rnk

Differential Revision: https://reviews.llvm.org/D52706

llvm-svn: 343627
2018-10-02 20:28:15 +00:00
Aaron Smith 802b033d78 [CodeView] Emit function options for subprogram and member functions
Summary:
Use the newly added DebugInfo (DI) Trivial flag, which indicates if a C++ record is trivial or not, to determine Codeview::FunctionOptions.

Clang and MSVC generate slightly different Codeview for C++ records. For example, here is the C++ code for a class with a defaulted ctor,

       class C {
       public:
         C() = default;
       };

Clang will produce a LF for the defaulted ctor while MSVC does not. For more details, refer to FIXMEs in the test cases in "function-options.ll" included with this set of changes.


Reviewers: zturner, rnk, llvm-commits, aleksandr.urakov

Reviewed By: rnk

Subscribers: Hui, JDevlieghere

Differential Revision: https://reviews.llvm.org/D45123

llvm-svn: 343626
2018-10-02 20:21:05 +00:00
Matt Morehouse 4b1ec17fb0 Revert "X86, AArch64, ARM: Do not attach debug location to spill/reload instructions"
This reverts r343520 due to breakage of HWASan tests on Android.

llvm-svn: 343616
2018-10-02 18:35:44 +00:00
Reid Kleckner d5e4ec74e3 [codeview] Fix 32-bit x86 variable locations in realigned stack frames
Add the .cv_fpo_stackalign directive so that we can define $T0, or the
VFRAME virtual register, with it. This was overlooked in the initial
implementation because unlike MSVC, we push CSRs before allocating stack
space, so this value is only needed to describe local variable
locations. Variables that the compiler now addresses via ESP are instead
described as being stored at offsets from VFRAME, which for us is ESP
after alignment in the prologue.

This adds tests that show that we use the VFRAME register properly in
our S_DEFRANGE records, and that we emit the correct FPO data to define
it.

Fixes PR38857

llvm-svn: 343603
2018-10-02 16:43:52 +00:00
Reid Kleckner 9ea2c01264 [codeview] Emit S_FRAMEPROC and use S_DEFRANGE_FRAMEPOINTER_REL
Summary:
Before this change, LLVM would always describe locals on the stack as
being relative to some specific register, RSP, ESP, EBP, ESI, etc.
Variables in stack memory are pretty common, so there is a special
S_DEFRANGE_FRAMEPOINTER_REL symbol for them. This change uses it to
reduce the size of our debug info.

On top of the size savings, there are cases on 32-bit x86 where local
variables are addressed from ESP, but ESP changes across the function.
Unlike in DWARF, there is no FPO data to describe the stack adjustments
made to push arguments onto the stack and pop them off after the call,
which makes it hard for the debugger to find the local variables in
frames further up the stack.

To handle this, CodeView has a special VFRAME register, which
corresponds to the $T0 variable set by our FPO data in 32-bit.  Offsets
to local variables are instead relative to this value.

This is part of PR38857.

Reviewers: hans, zturner, javed.absar

Subscribers: aprantl, hiraditya, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D52217

llvm-svn: 343543
2018-10-01 21:59:45 +00:00
Matthias Braun 3e081703c3 X86, AArch64, ARM: Do not attach debug location to spill/reload instructions
Spill/reload instructions are artificially generated by the compiler and
have no relation to the original source code. So the best thing to do is
not attach any debug location to them (instead of just taking the next
debug location we find on following instructions).

Differential Revision: https://reviews.llvm.org/D52125

llvm-svn: 343520
2018-10-01 18:56:39 +00:00
Zachary Turner a5e3e02602 [PDB] Add support for dumping Typedef records.
These work a little differently because they are actually in
the globals stream and are treated as symbol records, even though
DIA presents them as types.  So this also adds the necessary
infrastructure to cache records that live somewhere other than
the TPI stream as well.

llvm-svn: 343507
2018-10-01 17:55:38 +00:00
Zachary Turner 518cb2d560 [PDB] Add native support for dumping array types.
llvm-svn: 343412
2018-09-30 16:19:18 +00:00
Zachary Turner 9be3b6a18b [PDB] Fix this test for real.
I was able to test this fix on an actual Windows machine
so this should get the bot green again.

llvm-svn: 343400
2018-09-30 03:57:49 +00:00
Zachary Turner 6e6d545d24 Only dump the types we need in the test.
We added support for dumping pointers but pointers to arrays
won't correctly dump until we add support for dumping arrays.
Instead of trying to dump everything, which this test isn't
even interested in, just dump enums and typedefs.

llvm-svn: 343398
2018-09-30 00:51:54 +00:00
Zachary Turner 6ca6a03c51 [PDB] Better native API support for pointers.
We didn't properly detect when a pointer was a member
pointer, and when that was the case we were not
properly returning class parent info.  This caused
member pointers to render incorrectly in pretty mode.
However, we didn't even have pretty tests for pointers
in native mode, so those are also added now to ensure
this.

llvm-svn: 343393
2018-09-29 23:28:19 +00:00
Hsiangkai Wang 55321d82bd [DebugInfo] Do not generate address info for removed debug labels.
In some senario, LLVM will remove llvm.dbg.labels in IR. For example,
when the labels are in unreachable blocks, these labels will not
be generated in LLVM IR. In the case, these debug labels will have
address zero as their address. It is not legal address for debugger to
set breakpoints or query sources. So, the patch inhibits the address info
(DW_AT_low_pc) of removed labels.

Fix build failed in BuildBot, clang-stage1-cmake-RA-incremental, on macOS.

Differential Revision: https://reviews.llvm.org/D51908

llvm-svn: 343062
2018-09-26 04:19:23 +00:00
Yury Delendik 7c18d6083a [WebAssembly] Move/clone DBG_VALUE during WebAssemblyRegStackify pass
Summary:
The MoveForSingleUse or MoveAndTeeForMultiUse functions move wasm instructions,
however DBG_VALUE stay unchanged -- moving or cloning these.

Reviewers: dschuff

Reviewed By: dschuff

Subscribers: mattd, MatzeB, dschuff, sbc100, jgravelle-google, aheejin, sunfish, llvm-commits, aardappel

Tags: #debug-info

Differential Revision: https://reviews.llvm.org/D49034

llvm-svn: 343007
2018-09-25 18:59:34 +00:00
Justin Bogner ef2ae740c6 Revert "[DebugInfo] Do not generate address info for removed debug labels."
The added test is failing on macOS:

  http://green.lab.llvm.org/green/job/clang-stage1-cmake-RA-incremental/53550/

This reverts r342943.

llvm-svn: 342993
2018-09-25 17:29:30 +00:00
Hsiangkai Wang 9c2463622d [DebugInfo] Do not generate address info for removed debug labels.
In some senario, LLVM will remove llvm.dbg.labels in IR. For example,
when the labels are in unreachable blocks, these labels will not
be generated in LLVM IR. In the case, these debug labels will have
address zero as their address. It is not legal address for debugger to
set breakpoints or query sources. So, the patch inhibits the address info
(DW_AT_low_pc) of removed labels.

Differential Revision: https://reviews.llvm.org/D51908

llvm-svn: 342943
2018-09-25 06:09:50 +00:00
Zachary Turner 6345e84dde [NativePDB] Add support for reading function signatures.
This adds support for parsing function signature records and returning
them through the native DIA interface.

llvm-svn: 342780
2018-09-21 22:36:28 +00:00
Zachary Turner 355ffb0032 [PDB] Add native reading support for UDT / class types.
This allows the native reader to find records of class/struct/
union type and dump them.  This behavior is tested by using the
diadump subcommand against golden output produced by actual DIA
SDK on the same PDB file, and again using pretty -native to
confirm that we actually dump the classes.  We don't find class
members or anything like that yet, for now it's just the class
itself.

llvm-svn: 342779
2018-09-21 22:36:04 +00:00
Zachary Turner cfa1d499f9 [PDB] Add the ability to map forward references to full decls.
Some records point to an LF_CLASS, LF_UNION, LF_STRUCTURE, or LF_ENUM
which is a forward reference and doesn't contain complete debug
information. In these cases, we'd like to be able to quickly locate the
full record. The TPI stream stores an array of pre-computed record hash
values, one for each type record. If we pre-process this on startup, we
can build a mapping from hash value -> {list of possible matching type
indices}. Since hashes of full records are only based on the name and or
unique name and not the full record contents, we can then use forward
ref record to compute the hash of what *would* be the full record by
just hashing the name, use this to get the list of possible matches, and
iterate those looking for a match on name or unique name.

llvm-pdbutil is updated to resolve forward references for the purposes
of testing (plus it's just useful).

Differential Revision: https://reviews.llvm.org/D52283

llvm-svn: 342656
2018-09-20 15:50:13 +00:00
George Rimar 425f75172f [DWARF] - Emit the correct value for DW_AT_addr_base.
Currently, we emit DW_AT_addr_base that points to the beginning of
the .debug_addr section. That is not correct for the DWARF5 case because address
table contains the header and the attribute should point to the first entry
following the header.

This is currently the reason why LLDB does not work with such executables correctly.
Patch fixes the issue.

Differential revision: https://reviews.llvm.org/D52168

llvm-svn: 342635
2018-09-20 09:17:36 +00:00
Michael Berg 120ca61d7d [WEB] add new flags to a DebugInfo lit test
llvm-svn: 342598
2018-09-19 22:56:14 +00:00
Simon Pilgrim 2d0f20cc04 [X86] Handle COPYs of physregs better (regalloc hints)
Enable enableMultipleCopyHints() on X86.

Original Patch by @jonpa:

While enabling the mischeduler for SystemZ, it was discovered that for some reason a test needed one extra seemingly needless COPY (test/CodeGen/SystemZ/call-03.ll). The handling for that is resulted in this patch, which improves the register coalescing by providing not just one copy hint, but a sorted list of copy hints. On SystemZ, this gives ~12500 less register moves on SPEC, as well as marginally less spilling.

Instead of improving just the SystemZ backend, the improvement has been implemented in common-code (calculateSpillWeightAndHint(). This gives a lot of test failures, but since this should be a general improvement I hope that the involved targets will help and review the test updates.

Differential Revision: https://reviews.llvm.org/D38128

llvm-svn: 342578
2018-09-19 18:59:08 +00:00
Zachary Turner c41ce8355f [PDB] Better support for enumerating pointer types.
There were several issues with the previous implementation.

1) There were no tests.
2) We didn't support creating PDBSymbolTypePointer records for
   builtin types since those aren't described by LF_POINTER
   records.
3) We didn't support a wide enough variety of builtin types even
   ignoring pointers.

This patch fixes all of these issues.  In order to add tests,
it's helpful to be able to ignore the symbol index id hierarchy
because it makes the golden output from the DIA version not match
our output, so I've extended the dumper to disable dumping of id
fields.

llvm-svn: 342493
2018-09-18 16:35:05 +00:00
Zachary Turner bdf0381e21 [PDB] Make the native reader support enumerators.
Previously we would dump the names of enum types, but not their
enumerator values.  This adds support for enumerator values.  In
doing so, we have to introduce a general purpose mechanism for
caching symbol indices of field list members.  Unlike global
types, FieldList members do not have a TypeIndex.  So instead,
we identify them by the pair {TypeIndexOfFieldList, IndexInFieldList}.

llvm-svn: 342415
2018-09-17 21:08:11 +00:00
Zachary Turner 4727ac2394 [PDB] Make the native reader support modified types.
Previously for cv-qualified types, we would just ignore them
and they would never get printed.  Now we can enumerate them
and cache them like any other symbol type.

llvm-svn: 342414
2018-09-17 21:07:48 +00:00
Alexander Kornienko e74e0f11d1 Revert "[DWARF] reposting r342048, which was reverted in r342056 due to buildbot errors. Adjusted 2 test cases for ARM and darwin and fixed a bug with the original change in dsymutil."
This reverts commit r342218. Due to a number of failures under TSAN. An isolated
test case is being worked on.

llvm-svn: 342399
2018-09-17 15:40:01 +00:00
Zachary Turner a98ee586bf [PDB] Make the pretty dumper output modified types.
Currently if we got something like `const Foo` we'd ignore it and
just rely on printing the unmodified `Foo` later on.  However,
for testing the native reading code we really would like to be able
to see these so that we can verify that the native reader can
actually handle them.  Instead of printing out the full type though,
just print out the header.

llvm-svn: 342295
2018-09-14 22:29:19 +00:00
Adrian Prantl 16f58d1850 Fix debug info for SelectionDAG legalization of DAG nodes with two results.
This patch fixes the debug info handling for SelectionDAG legalization
of DAG nodes with two results. When an replaced SDNode has more than
one result, transferDbgValues was always copying the SDDbgValue from
the first result and attaching them to all members. In reality
SelectionDAG::ReplaceAllUsesWith() is given an array of SDNodes
(though the type signature doesn't make this obvious (cf. the call
site code in ReplaceNode()).

rdar://problem/44162227

Differential Revision: https://reviews.llvm.org/D52112

llvm-svn: 342264
2018-09-14 19:38:45 +00:00
Wolfgang Pieb 55dbac9f07 [DWARF] reposting r342048, which was reverted in r342056 due to buildbot
errors.
Adjusted 2 test cases for ARM and darwin and fixed a bug with the original
change in dsymutil.

llvm-svn: 342218
2018-09-14 09:14:10 +00:00
Jonas Devlieghere 64c901d2b1 [MC/Dwarf] Unclamp DWARF linetables format on Darwin.
In r319995, we fixed the line table format to version 2 on Darwin
because dsymutil didn't yet understand the new format which caused test
failures for the LLDB bots. This has been resolved in the meantime so
there's no reason to keep this limitation.

rdar://problem/35968332

llvm-svn: 342136
2018-09-13 13:13:50 +00:00
Wolfgang Pieb 233bc73047 Reverting r342048, which caused UBSan failures in dsymutil.
llvm-svn: 342056
2018-09-12 14:40:04 +00:00
Wolfgang Pieb 3a8781cf6c [DWARF] Refactoring range list dumping to fold DWARF v4 functionality into v5 handling
Eliminating some duplication of rangelist dumping code at the expense of
some version-dependent code in dump and extract routines.

Reviewer: dblaikie, JDevlieghere, vleschuk

Differential revision: https://reviews.llvm.org/D51081

llvm-svn: 342048
2018-09-12 12:01:19 +00:00
Reid Kleckner a6f64265ea [codeview] Decode and dump FP regs from S_FRAMEPROC records
Summary:
There are two registers encoded in the S_FRAMEPROC flags: one for locals
and one for parameters. The encoding is described by the
ExpandEncodedBasePointerReg function in cvinfo.h. Two bits are used to
indicate one of four possible values:

  0: no register - Used when there are no variables.
  1: SP / standard - Variables are stored relative to the standard SP
     for the ISA.
  2: FP - Variables are addressed relative to the ISA frame
     pointer, i.e. EBP on x86. If realignment is required, parameters
     use this. If a dynamic alloca is used, locals will be EBP relative.
  3: Alternative - Variables are stored relative to some alternative
     third callee-saved register. This is required to address highly
     aligned locals when there are dynamic stack adjustments. In this
     case, both the incoming SP saved in the standard FP and the current
     SP are at some dynamic offset from the locals. LLVM uses ESI in
     this case, MSVC uses EBX.

Most of the changes in this patch are to pass around the CPU so that we
can decode these into real, named architectural registers.

Subscribers: hiraditya

Differential Revision: https://reviews.llvm.org/D51894

llvm-svn: 341999
2018-09-11 22:00:50 +00:00
David Blaikie 4ec5a9159b llvm-symbolizer: Fix bug related to TUs interfering with symbolizing
With the merge of TUs and CUs into a single container, some code that
relied on the CU range having an ordered range of contiguous addresses
(for locating a CU at a given offset) broke. But the units from
debug_info (currently only CUs, but CUs and TUs in DWARFv5) are in a
contiguous sub-range of that container - searching only through that
subrange is still valid & so do that.

llvm-svn: 341889
2018-09-11 02:04:45 +00:00
Matt Arsenault 72d27f5525 AMDGPU: Fix tests using old number for constant address space
llvm-svn: 341770
2018-09-10 02:54:25 +00:00
Zachary Turner 0119e38491 Fix some of the PDB tests.
They were unintentionally calling DIA directly, which requires
Windows.  We need to pass the -native flag, and this then required
fixing up one or two tests.

llvm-svn: 341731
2018-09-07 23:36:08 +00:00
Zachary Turner da4b63ab9a [PDB] Support pointer types in the native reader.
In order to start testing this, I've added a new mode to
llvm-pdbutil which is only really useful for writing tests.
It just dumps the value of raw fields in record format.
This isn't really ideal and it won't allow us to test some
important cases, but it's better than nothing for now.

llvm-svn: 341729
2018-09-07 23:21:33 +00:00
Reid Kleckner ee0e8bab2a [codeview] Improve readobj FPO dumper and pdbutil register names
The improved dumping helps me investigate PR38857.

llvm-svn: 341695
2018-09-07 18:48:27 +00:00
David Stenberg 45acc9610b [DebugInfo] Handle stack slot offsets for spilled sub-registers in LDV
Summary:
Extend LDV so that stack slot offsets for spilled sub-registers
are added to the emitted debug locations. This is accomplished
by querying InstrInfo::getStackSlotRange().

With this change, LDV will add a DW_OP_plus_uconst operation to
the expression if a sub-register is spilled. Later on, PEI will
add an offset operation for the stack slot, meaning that we will
get expressions of the forms:

 * {DW_OP_constu #fp-offset, DW_OP_minus,
    DW_OP_plus_uconst #subreg-offset}

 * {DW_OP_plus_const #fp-offset,
    DW_OP_minus, DW_OP_plus_uconst #subreg-offset}

The two offset operations should ideally be merged.

Reviewers: rnk, aprantl, stoklund

Reviewed By: aprantl

Subscribers: dblaikie, bjope, nemanjai, JDevlieghere, llvm-commits

Tags: #debug-info

Differential Revision: https://reviews.llvm.org/D51612

llvm-svn: 341659
2018-09-07 13:54:07 +00:00
Hsiangkai Wang 760c1ab199 [DebugInfo] Do not generate label debug info if it has been processed.
In DwarfDebug::collectEntityInfo(), if the label entity is processed in
DbgLabels list, it means the label is not optimized out. There is no
need to generate debug info for it with null position.

llvm-svn: 341513
2018-09-06 02:22:06 +00:00
Jonas Devlieghere 965b598b2a [DebugInfo] Normalize common kinds of DWARF sub-expressions.
Normalize common kinds of DWARF sub-expressions to make debug info
encoding a bit more compact:

  DW_OP_constu [X < 32] -> DW_OP_litX
  DW_OP_constu [all ones] -> DW_OP_lit0, DW_OP_not (64-bit only)

Differential revision: https://reviews.llvm.org/D51640

llvm-svn: 341457
2018-09-05 10:18:36 +00:00
Hsiangkai Wang b2b7f5f6d7 [DebugInfo] Fix bug in LiveDebugVariables.
In lib/CodeGen/LiveDebugVariables.cpp, it uses std::prev(MBBI) to
get DebugValue's SlotIndex. However, the previous instruction may be
also a debug instruction. It could not use a debug instruction to query
SlotIndex in mi2iMap.

Scan all debug instructions and use the first debug instruction to query
SlotIndex for following debug instructions. Only handle DBG_VALUE in
handleDebugValue().

Differential Revision: https://reviews.llvm.org/D50621

llvm-svn: 341446
2018-09-05 05:58:53 +00:00
Hsiangkai Wang e0dcc28a4d Revert "[DebugInfo] Fix bug in LiveDebugVariables."
This reverts commit 8f548ff2a1819e1bc051e8218584f1a3d2cf178a.

buildbot failure in LLVM on clang-ppc64be-linux
http://lab.llvm.org:8011/builders/clang-ppc64le-linux/builds/19765

llvm-svn: 341290
2018-09-02 16:35:42 +00:00
Hsiangkai Wang 1368434b49 [DebugInfo] Fix bug in LiveDebugVariables.
In lib/CodeGen/LiveDebugVariables.cpp, it uses std::prev(MBBI) to
get DebugValue's SlotIndex. However, the previous instruction may be
also a debug instruction. It could not use a debug instruction to query
SlotIndex in mi2iMap.

Scan all debug instructions and use the first debug instruction to query
SlotIndex for following debug instructions. Only handle DBG_VALUE in
handleDebugValue().

Differential Revision: https://reviews.llvm.org/D50621

llvm-svn: 341289
2018-09-02 15:57:22 +00:00
Alexandre Ganea 6a7efef4af [DebugInfo] Common behavior for error types
Following D50807, and heading towards D50664, this intermediary change does the following:

1. Upgrade all custom Error types in llvm/trunk/lib/DebugInfo/ to use the new StringError behavior (D50807).
2. Implement std::is_error_code_enum and make_error_code() for DebugInfo error enumerations.
3. Rename GenericError -> PDBError (the file will be renamed in a subsequent commit)
4. Update custom error messages to follow the same formatting: (\w\s*)+\.
5. Keep generic "file not found" (ENOENT) errors as they are in PDB code. Previously, there used to be a custom enumeration for that purpose.
6. Remove a few extraneous LF in log() implementations. Printing LF is a responsability at a higher level, not at the error level.

Differential Revision: https://reviews.llvm.org/D51499

llvm-svn: 341228
2018-08-31 17:41:58 +00:00
Reid Kleckner 689f773317 [codeview] Clean up machinery for deferring .cv_loc emission
Now that we create the label at the point of the directive, we don't
need to set the "current CV location", and then later when we emit the
next instruction, create a label for it and emit it.

DWARF still defers the labels used in .debug_loc until the next
instruction or value, for reasons unknown.

llvm-svn: 340883
2018-08-28 23:25:59 +00:00
Pavel Labath 10d87abdc5 Clarify comment in the string-offsets-table-order.ll test
llvm-svn: 340826
2018-08-28 14:46:29 +00:00
David Blaikie 6dd452b514 DebugInfo: Fix skipping CUs in DWARFv5 debug_names table
My previoust test case had skipped CUs from one TU out of a two-TU LTO
scenario, which meant the CU index wasn't needed (as it was unambiguous
which CU a table entry applied to) - expanding the test to use 3 TUs,
skipping one (so long as it's not the last one) shows the indexes are
miscomputed. Fix that with a little indirection for the index.

llvm-svn: 340646
2018-08-24 20:31:05 +00:00
David Blaikie 2a813ef208 DebugInfo: Improve debug location merging
Fix a set of related bugs:

* Considering two locations as equivalent when their lines are the same
but their scopes are different causes erroneous debug info that
attributes a commoned call to be attributed to one of the two calls it
was commoned from.

* The previous code to compute a new location's scope was inaccurate and
would use the inlinedAt that was the /parent/ of the inlinedAt that is
the nearest common one, and also used that parent scope instead of the
nearest common scope.

* Not generating new locations generally seemed like a lower quality
choice

There was some risk that generating more new locations could hurt object
size by making more fine grained line table entries, but it looks like
that was offset by the decrease in line table (& address & ranges) size
caused by more accurately computing the scope - which likely lead to
fewer range entries (more contiguous ranges) & reduced size that way.

All up with these changes I saw minor reductions (-1.21%, -1.77%) in
.rela.debug_ranges and .rela.debug_addr (in a fission, compressed debug
info build) as well as other minor size changes (generally reductinos)
across the board (-1.32% debug_info.dwo, -1.28% debug_loc.dwo). Measured
in an optimized (-O2) build of the clang binary.

If you are investigating a size regression in an optimized debug builds,
this is certainly a patch to look into - and I'd be happy to look into
any major regressions found & see what we can do to address them.

llvm-svn: 340583
2018-08-23 22:35:58 +00:00
Chandler Carruth 8505dcf745 Revert r340508: [DebugInfo] Fix bug in LiveDebugVariables.
This patch's test case relies on debug prints which isn't generally an
OK way to test stuff in LLVM and fails whenever asserts aren't enabled.
I've send a heads-up to the commit and detailed comments on the review.

llvm-svn: 340513
2018-08-23 05:39:02 +00:00
Hsiangkai Wang 97edcbc4e0 [DebugInfo] Fix bug in LiveDebugVariables.
In lib/CodeGen/LiveDebugVariables.cpp, it uses std::prev(MBBI) to
get DebugValue's SlotIndex. However, the previous instruction may be
also a debug instruction. It could not use a debug instruction to query
SlotIndex in mi2iMap.

Scan all debug instructions and use the first debug instruction to query
SlotIndex for following debug instructions. Only handle DBG_VALUE in
handleDebugValue().

Differential Revision: https://reviews.llvm.org/D50621

llvm-svn: 340508
2018-08-23 03:28:24 +00:00
Vedant Kumar a459b9f757 Avoid dbg.value use-before-def in a few tests (NFC)
This is preparation for landing a use-before-def verifier for debug
intrinsics (D46100).

As a drive-by, remove `tail` from debug intrinsic calls because it
doesn't mean anything in that context.

llvm-svn: 340366
2018-08-21 23:42:08 +00:00
Yury Delendik 132fc5a861 Update DBG_VALUE register operand during LiveInterval operations
Summary:
Handling of DBG_VALUE in ConnectedVNInfoEqClasses::Distribute() was fixed in
PR16110. However DBG_VALUE register operands are not getting updated. This
patch properly resolves the value location.

Reviewers: MatzeB, vsk

Reviewed By: MatzeB

Subscribers: kparzysz, thegameg, vsk, MatzeB, dschuff, sbc100, jgravelle-google, aheejin, sunfish, llvm-commits

Tags: #debug-info

Differential Revision: https://reviews.llvm.org/D48994

llvm-svn: 340310
2018-08-21 17:48:28 +00:00
Hsiangkai Wang 68c706ceb7 [DebugInfo] In FastISel, convert llvm.dbg.label to DBG_LABEL MI.
Convert llvm.dbg.label(!label_metadata) to DBG_LABEL !label_metadata.

Differential Revision: https://reviews.llvm.org/D50622

llvm-svn: 340122
2018-08-18 14:55:34 +00:00
Vedant Kumar 8cd64580b7 Remove a hardcoded address in test/DebugInfo/X86/vla-multi.ll
This relaxes a test to make it less brittle.

llvm-svn: 340068
2018-08-17 18:39:19 +00:00
Hsiangkai Wang 2532ac880a [DebugInfo] Generate DWARF debug information for labels. (Fix leak problems)
There are two forms for label debug information in DWARF format.

1. Labels in a non-inlined function:

DW_TAG_label
  DW_AT_name
  DW_AT_decl_file
  DW_AT_decl_line
  DW_AT_low_pc

2. Labels in an inlined function:

DW_TAG_label
  DW_AT_abstract_origin
  DW_AT_low_pc

We will collect label information from DBG_LABEL. Before every DBG_LABEL,
we will generate a temporary symbol to denote the location of the label.
The symbol could be used to get DW_AT_low_pc afterwards. So, we create a
mapping between 'inlined label' and DBG_LABEL MachineInstr in DebugHandlerBase.
The DBG_LABEL in the mapping is used to query the symbol before it.

The AbstractLabels in DwarfCompileUnit is used to process labels in inlined
functions.

We also keep a mapping between scope and labels in DwarfFile to help to
generate correct tree structure of DIEs.

It also generates label debug information under global isel.

Differential Revision: https://reviews.llvm.org/D45556

llvm-svn: 340039
2018-08-17 15:22:04 +00:00
David Blaikie 0e03047e85 DebugInfo: Remove command line (& target-based) disabling of pubnames in favor of metadata
Now that Clang disables NVPTX pubnames via metadata there's no need for
this fallback to target detection in the backend.

llvm-svn: 339970
2018-08-16 23:57:15 +00:00
David Blaikie 66cf14d06b DebugInfo: Add metadata support for disabling DWARF pub sections
In cases where the debugger load time is a worthwhile tradeoff (or less
costly - such as loading from a DWP instead of a variety of DWOs
(possibly over a high-latency/distributed filesystem)) against object
file size, it can be reasonable to disable pubnames and corresponding
gdb-index creation in the linker.

A backend-flag version of this was implemented for NVPTX in
D44385/r327994 - which was fine for NVPTX which wouldn't mix-and-match
CUs. Now that it's going to be a user-facing option (likely powered by
"-gno-pubnames", the same as GCC) it should be encoded in the
DICompileUnit so it can vary per-CU.

After this, likely the NVPTX support should be migrated to the metadata
& the previous flag implementation should be removed.

Reviewers: aprantl

Differential Revision: https://reviews.llvm.org/D50213

llvm-svn: 339939
2018-08-16 21:29:55 +00:00
Reid Kleckner bd5d71229d [codeview] Use push_macro to avoid conflicts instead of a prefix
Summary:
This prefix was added in r333421, and it changed our dumper output to
say things like "CVRegEAX" instead of just "EAX". That's a functional
change that I'd rather avoid.

I tested GCC, Clang, and MSVC, and all of them support #pragma
push_macro. They don't issue warnings whem the macro is not defined
either.

I don't have a Mac so I can't test the real termios.h header, but I
looked at the termios.h sources online and looked for other conflicts.
I saw only the CR* macros, so those are the ones we work around.

Reviewers: zturner, JDevlieghere

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D50851

llvm-svn: 339907
2018-08-16 17:34:31 +00:00
Bruno Cardoso Lopes f446282aad Revert "[DebugInfo] Generate DWARF debug information for labels. (Fix leak problems)"
This reverts commit cb8c5e417d55141f3f079a8a876e786f44308336 / r339676.

This causing a test to fail in http://green.lab.llvm.org/green/job/clang-stage1-configure-RA/48406/

    LLVM :: DebugInfo/Generic/debug-label.ll

llvm-svn: 339700
2018-08-14 17:54:41 +00:00
Hsiangkai Wang ccae278938 [DebugInfo] Generate DWARF debug information for labels. (Fix leak problems)
There are two forms for label debug information in DWARF format.

1. Labels in a non-inlined function:

DW_TAG_label
  DW_AT_name
  DW_AT_decl_file
  DW_AT_decl_line
  DW_AT_low_pc

2. Labels in an inlined function:

DW_TAG_label
  DW_AT_abstract_origin
  DW_AT_low_pc

We will collect label information from DBG_LABEL. Before every DBG_LABEL,
we will generate a temporary symbol to denote the location of the label.
The symbol could be used to get DW_AT_low_pc afterwards. So, we create a
mapping between 'inlined label' and DBG_LABEL MachineInstr in DebugHandlerBase.
The DBG_LABEL in the mapping is used to query the symbol before it.

The AbstractLabels in DwarfCompileUnit is used to process labels in inlined
functions.

We also keep a mapping between scope and labels in DwarfFile to help to
generate correct tree structure of DIEs.

It also generates label debug information under global isel.

Differential Revision: https://reviews.llvm.org/D45556

llvm-svn: 339676
2018-08-14 13:50:59 +00:00
Craig Topper 570d47a010 [X86] Change the MOV32ri64 pseudo instruction to def a GR64 directly instead of wrapping it in a SUBREG_TO_REG.
Now we switch to the subregister in expandPostRAPseudos where we already switched the opcode.

This simplifies a few isel patterns that used the pseudo directly. And magically seems to have improved our ability to CSE it in the undef-label.ll test.

llvm-svn: 339496
2018-08-11 05:33:00 +00:00
Petr Hosek eb46c95c3e [CMake] Use normalized Windows target triples
Changes the default Windows target triple returned by
GetHostTriple.cmake from the old environment names (which we wanted to
move away from) to newer, normalized ones. This also requires updating
all tests to use the new systems names in constraints.

Differential Revision: https://reviews.llvm.org/D47381

llvm-svn: 339307
2018-08-09 02:16:18 +00:00
Paul Robinson 508b081514 [DWARF] Verifier now handles .debug_types sections.
Differential Revision: https://reviews.llvm.org/D50466

llvm-svn: 339302
2018-08-08 23:50:22 +00:00
Jonas Devlieghere caacedb03e [DebugInfo] Fine tune emitting flags as part of the producer
When using APPLE extensions, don't duplicate the compiler invocation's
flags both in AT_producer and AT_APPLE_flags.

Differential revision: https://reviews.llvm.org/D50453

llvm-svn: 339268
2018-08-08 16:33:22 +00:00
Pavel Labath 2f0881160c [DebugInfo] Reduce debug_str_offsets section size
Summary:
The accelerator tables use the debug_str section to store their strings.
However, they do not support the indirect method of access that is
available for the debug_info section (DW_FORM_strx et al.).

Currently our code is assuming that all strings can/will be referenced
indirectly, and puts all of them into the debug_str_offsets section.
This is generally true for regular (unsplit) dwarf, but in the DWO case,
most of the strings in the debug_str section will only be used from the
accelerator tables. Therefore the contents of the debug_str_offsets
section will be largely unused and bloating the main executable.

This patch rectifies this by teaching the DwarfStringPool to
differentiate between strings accessed directly and indirectly. When a
user inserts a string into the pool it has to declare whether that
string will be referenced directly or not. If at least one user requsts
indirect access, that string will be assigned an index ID and put into
debug_str_offsets table. Otherwise, the offset table is skipped.

This approach reduces the overall binary size (when compiled with
-gdwarf-5 -gsplit-dwarf) in my tests by about 2% (debug_str_offsets is
shrunk by 99%).

Reviewers: probinson, dblaikie, JDevlieghere

Subscribers: aprantl, mgrang, llvm-commits

Differential Revision: https://reviews.llvm.org/D49493

llvm-svn: 339122
2018-08-07 09:54:52 +00:00
Jonas Devlieghere 3a92c5c1d3 [DebugInfo/Verifier] Don't emit error for missing module in index
We don't expect module names to be present in the index. This patch adds
DW_TAG_module to the blacklist.

Differential revision: https://reviews.llvm.org/D50237

llvm-svn: 338878
2018-08-03 12:01:43 +00:00
Lei Liu 8e422b8403 [AArch64] DWARF: do not generate AT_location for thread local
AArch64 ELF ABI does not define a static relocation type for TLS offset within
a module, which makes it impossible for compiler to generate a valid
DW_AT_location content for thread local variables. Currently LLVM generates an
invalid R_AARCH64_ABS64 relocation at the DW_AT_location field for a TLS
variable. That causes trouble for linker because thread local variable does
not have an absolute address at link time. AArch64 GCC solves the problem by
not generating DW_AT_location for thread local variables. We should do the
same in LLVM.

Differential Revision: https://reviews.llvm.org/D43860

llvm-svn: 338655
2018-08-01 23:46:49 +00:00
Alexey Bataev d4dd7215f6 [DEBUGINFO] Disable emission of the dwarf sections, but allow directives.
Summary:
Added an option that allows to emit only '.loc' and '.file' kind debug
directives, but disables emission of the DWARF sections. Required for
NVPTX target to support profiling. It requires '.loc' and '.file'
directives, but does not require any DWARF sections for the profiler.

Reviewers: probinson, echristo, dblaikie

Subscribers: aprantl, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D46021

llvm-svn: 338616
2018-08-01 19:38:20 +00:00
Jonas Devlieghere 8acb74e01f [MC] Report fatal error for DWARF types for non-ELF object files
Getting the DWARF types section is only implemented for ELF object
files. We already disabled emitting debug types in clang (r337717), but
now we also report an fatal error (rather than crashing) when trying to
obtain this section in MC. Additionally we ignore the generate debug
types flag for unsupported target triples.

See PR38190 for more information.

Differential revision: https://reviews.llvm.org/D50057

llvm-svn: 338527
2018-08-01 12:53:06 +00:00
Victor Leschuk 64e0c56717 [DWARF] Basic support for producing DWARFv5 .debug_addr section
This revision implements support for generating DWARFv5 .debug_addr section.
The implementation is pretty straight-forward: we just check the dwarf version
and emit section header if needed.

Reviewers: aprantl, dblaikie, probinson

Reviewed by: dblaikie

Differential Revision: https://reviews.llvm.org/D50005

llvm-svn: 338487
2018-08-01 05:48:06 +00:00
Hsiangkai Wang 5c63af0d04 [DebugInfo] Generate fixups as emitting DWARF .debug_line.
It is necessary to generate fixups in .debug_line as relaxation is
enabled due to the address delta may be changed after relaxation.

DWARF will record the mappings of lines and addresses in
.debug_line section. It will encode the information using special
opcodes, standard opcodes and extended opcodes in Line Number
Program. I use DW_LNS_fixed_advance_pc to encode fixed length
address delta and DW_LNE_set_address to encode absolute address
to make it possible to generate fixups in .debug_line section.

Differential Revision: https://reviews.llvm.org/D46850

llvm-svn: 338477
2018-08-01 02:18:06 +00:00
Alexandre Ganea b92d3ad762 [CodeView] Add coverage test for r338308 (Fixed crash in type merging)
llvm-svn: 338423
2018-07-31 19:30:03 +00:00
Alexandre Ganea ee8a720051 [CodeView] Minimal support for S_UNAMESPACE records
Differential Revision: https://reviews.llvm.org/D50007

llvm-svn: 338417
2018-07-31 19:15:50 +00:00
Vlad Tsyrklevich 48ed9acede Revert "[DebugInfo] Generate DWARF debug information for labels."
This reverts commits r338390 and r338398, they were causing LSan
failures on the ASan bot.

llvm-svn: 338408
2018-07-31 18:10:37 +00:00
Hsiangkai Wang 68c6860434 [DebugInfo] Fix build failed in 'clang-cmake-armv8-full'.
Builder clang-cmake-armv8-full failed due to the assembly 'comment'
notation is not '#' in the target. So, I use CHECK-SAME to avoid to
check the comment notation in the same line in the test case.

llvm-svn: 338398
2018-07-31 16:22:09 +00:00
Hsiangkai Wang cbc58ada99 [DebugInfo] Generate DWARF debug information for labels.
There are two forms for label debug information in DWARF format.

1. Labels in a non-inlined function:

DW_TAG_label
  DW_AT_name
  DW_AT_decl_file
  DW_AT_decl_line
  DW_AT_low_pc

2. Labels in an inlined function:

DW_TAG_label
  DW_AT_abstract_origin
  DW_AT_low_pc

We will collect label information from DBG_LABEL. Before every DBG_LABEL,
we will generate a temporary symbol to denote the location of the label.
The symbol could be used to get DW_AT_low_pc afterwards. So, we create a
mapping between 'inlined label' and DBG_LABEL MachineInstr in DebugHandlerBase.
The DBG_LABEL in the mapping is used to query the symbol before it.

The AbstractLabels in DwarfCompileUnit is used to process labels in inlined
functions.

We also keep a mapping between scope and labels in DwarfFile to help to
generate correct tree structure of DIEs.

It also generates label debug information under global isel.

Differential Revision: https://reviews.llvm.org/D45556

llvm-svn: 338390
2018-07-31 14:48:32 +00:00
Wolfgang Pieb 9ea65082ff [DWARF v5] Reposting r337981, which was reverted in r337997 due to a test failure in debuginfo_tests.
The test failure was caused by the compiler not emitting a __debug_ranges section with DWARF 4 and
earlier when no ranges are needed. The test checks for the existence regardless.

llvm-svn: 338081
2018-07-26 22:48:52 +00:00
Vedant Kumar b572f64212 [DebugInfo] LowerDbgDeclare: Add derefs when handling CallInst users
LowerDbgDeclare inserts a dbg.value before each use of an address
described by a dbg.declare. When inserting a dbg.value before a CallInst
use, however, it fails to append DW_OP_deref to the DIExpression.

The DW_OP_deref is needed to reflect the fact that a dbg.value describes
a source variable directly (as opposed to a dbg.declare, which relies on
pointer indirection).

This patch adds in the DW_OP_deref where needed. This results in the
correct values being shown during a debug session for a program compiled
with ASan and optimizations (see https://reviews.llvm.org/D49520). Note
that ConvertDebugDeclareToDebugValue is already correct -- no changes
there were needed.

One complication is that SelectionDAG is unable to distinguish between
direct and indirect frame-index (FRAMEIX) SDDbgValues. This patch also
fixes this long-standing issue in order to not regress integration tests
relying on the incorrect assumption that all frame-index SDDbgValues are
indirect. This is a necessary fix: the newly-added DW_OP_derefs cannot
be lowered properly otherwise. Basically the fix prevents a direct
SDDbgValue with DIExpression(DW_OP_deref) from being dereferenced twice
by a debugger. There were a handful of tests relying on this incorrect
"FRAMEIX => indirect" assumption which actually had incorrect
DW_AT_locations: these are all fixed up in this patch.

Testing:

- check-llvm, and an end-to-end test using lldb to debug an optimized
  program.
- Existing unit tests for DIExpression::appendToStack fully cover the
  new DIExpression::append utility.
- check-debuginfo (the debug info integration tests)

Differential Revision: https://reviews.llvm.org/D49454

llvm-svn: 338069
2018-07-26 20:56:53 +00:00
Alexey Bataev 4dd7558fab [DEBUGINFO, NVPTX] Emit correct debug information for local variables.
Summary:
NVPTX target dos not use register-based frame information. Instead it
relies on the artificial local_depot that is used instead of the frame
and the data for variables must be emitted relatively to this
local_depot.

Reviewers: tra, jlebar, echristo

Subscribers: jholewinski, aprantl, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D45963

llvm-svn: 338039
2018-07-26 16:29:52 +00:00
Alexey Bataev 7ae86fe71c [DEBUGINFO, NVPTX] Set `DW_AT_frame_base` to `DW_OP_call_frame_cfa`.
Summary:
For NVPTX target the value of `DW_AT_frame_base` attribute must be set
to `DW_OP_call_frame_cfa`.

Reviewers: tra, jlebar, echristo

Subscribers: jholewinski, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D45785

llvm-svn: 338036
2018-07-26 16:10:05 +00:00
Alex Lorenz 7d808c19ff Revert r337981: it breaks the debuginfo-tests
This commit caused a regression in the debuginfo-tests:

FAIL: debuginfo-tests :: apple-accel.cpp (40748 of 46595)
llvm-svn: 337997
2018-07-26 03:21:40 +00:00
Wolfgang Pieb 1d56b4ae40 [DWARF v5] Don't report an error when the .debug_rnglists section is empty or non-existent. Fixes PR38297.
Reviewer: JDevlieghere

Differential Revision: https://reviews.llvm.org/D49815
 

llvm-svn: 337993
2018-07-26 01:12:41 +00:00
Wolfgang Pieb c42087df7c [DWARF v5] Don't emit multiple DW_AT_rnglists_base attributes. Some refactoring of
range lists emissions and added test cases.

Reviewer: dblaikie

Differential Revision: https://reviews.llvm.org/D49522

llvm-svn: 337981
2018-07-25 23:03:22 +00:00
Shiva Chen f5938bfbf9 Revert "[DebugInfo] Generate DWARF debug information for labels."
This reverts commit b454fa1b4079b6c0a5b1565982d16516385838d7.

llvm-svn: 337812
2018-07-24 06:17:45 +00:00
Shiva Chen d6b2cdf9d4 [DebugInfo] Generate DWARF debug information for labels.
There are two forms for label debug information in DWARF format.

1. Labels in a non-inlined function:

DW_TAG_label
  DW_AT_name
  DW_AT_decl_file
  DW_AT_decl_line
  DW_AT_low_pc

2. Labels in an inlined function:

DW_TAG_label
  DW_AT_abstract_origin
  DW_AT_low_pc

We will collect label information from DBG_LABEL. Before every DBG_LABEL,
we will generate a temporary symbol to denote the location of the label.
The symbol could be used to get DW_AT_low_pc afterwards. So, we create a
mapping between 'inlined label' and DBG_LABEL MachineInstr in DebugHandlerBase.
The DBG_LABEL in the mapping is used to query the symbol before it.

The AbstractLabels in DwarfCompileUnit is used to process labels in inlined
functions.

We also keep a mapping between scope and labels in DwarfFile to help to
generate correct tree structure of DIEs.

Differential Revision: https://reviews.llvm.org/D45556

Patch by Hsiangkai Wang.

llvm-svn: 337799
2018-07-24 02:22:55 +00:00
Vedant Kumar d6ff43cc71 [Debugify] Export per-pass debug info loss statistics
Add a -debugify-export option to opt. This exports per-pass `debugify`
loss statistics to a file in CSV format.

For some interesting numbers on debug value loss during an -O2 build
of the sqlite3 amalgamation, see the review thread.

Differential Revision: https://reviews.llvm.org/D49003

llvm-svn: 337787
2018-07-24 00:41:29 +00:00
Wolfgang Pieb 439801ba1d [DWARF v5] Refactor range lists dumping by using a more generic way of handling tables of lists.
The intent is to use it for location list tables as well. Change is almost NFC with the exception
of the spelling of some strings used during dumping (all lowercase now).

Reviewer: JDevlieghere

Differential Revision: https://reviews.llvm.org/D49500

llvm-svn: 337763
2018-07-23 22:37:17 +00:00
Pavel Labath f9adc20aef [DebugInfo] Generate .debug_names section when it makes sense
Summary:
This patch makes us generate the debug_names section in response to some
user-facing commands (previously it was only generated if explicitly
selected via the -accel-tables option).

My goal was to make this work for DWARF>=5 (as it's an official part of
that standard), and also, as an extension, for DWARF<5 if one is
explicitly tuning for lldb as a debugger (because it brings a large
performance improvement there).

This is slightly complicated by the fact that the debug_names tables are
incompatible with the DWARF v4 type units (they assume that the type
units are in the debug_info section), and unfortunately, right now we
generate DWARF v4-style type units even for -gdwarf-5. For this reason,
I disable all accelerator tables if the user requested type unit
generation. I do this even for apple tables, as they have the same
problem (in fact generating type units for apple targets makes us crash
even before we get around to emitting the accelerator tables).

Reviewers: JDevlieghere, aprantl, dblaikie, echristo, probinson

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D49420

llvm-svn: 337544
2018-07-20 12:59:05 +00:00
Peter Collingbourne 4a653fa7f1 Rename __asan_gen_* symbols to ___asan_gen_*.
This prevents gold from printing a warning when trying to export
these symbols via the asan dynamic list after ThinLTO promotes them
from private symbols to external symbols with hidden visibility.

Differential Revision: https://reviews.llvm.org/D49498

llvm-svn: 337428
2018-07-18 22:23:14 +00:00
David Blaikie 71812e3001 Fix some tests that had (implied) duplicate mtriple
I 'fixed' one of these to use %llc_dwarf unnecessarily, so switch them
both back to using llc directly.

llvm-svn: 337423
2018-07-18 20:37:01 +00:00
David Blaikie d66140514d [DebugInfo] Dwarfv5: Avoid unnecessary base_address specifiers in rnglists
Since DWARFv5 rnglists are self descriptive and have distinct encodings
for base-relative (offset_pair) and absolute (start_length) entries,
there's no need to use a base address specifier when describing a lone
address range in a section.

Use that, and improve the test coverage a bit here to include cases like
this and others.

llvm-svn: 337411
2018-07-18 18:04:42 +00:00
Jonas Devlieghere 8afd926077 [dwarfdump] Pretty print DW_AT_APPLE_runtime_class
Instead of printing

  DW_AT_APPLE_runtime_class       (0x10)

we now print

  DW_AT_APPLE_runtime_class       (DW_LANG_ObjC)

llvm-svn: 337011
2018-07-13 16:06:17 +00:00
Petar Jovanovic be2e80af12 [LiveDebugValues] Tracking copying value between registers
During the execution of long functions or functions that have a lot of
inlined code it could come to the situation where tracked value could be
transferred from one register to another. The transfer is recognized only if
destination register is a callee saved register and if source register is
killed. We do not salvage caller-saved registers since there is a great
chance that killed register would outlive it.

Patch by Nikola Prica.

Differential Revision: https://reviews.llvm.org/D44016

llvm-svn: 336978
2018-07-13 08:24:26 +00:00
Wolfgang Pieb fcf3810cf7 [DWARF v5] Generate range list tables into the .debug_rnglists section. No support for split DWARF
and no use of DW_FORM_rnglistx with the DW_AT_ranges attribute.

Reviewer: aprantl

Differential Revision: https://reviews.llvm.org/D49214

llvm-svn: 336927
2018-07-12 18:18:21 +00:00
Francis Visoiu Mistrih 8b2ab91a5d [DebugInfo][X86] Add start-after flags to MIR tests
These tests would fail with -verify-machineinstrs because the MI
generated from the IR would be merged with the one already in the MIR
files, and we get the following error:

```
*** Bad machine code: Function has NoVRegs property but there are VReg operands ***
- function:    f
```

Differential Revision: https://reviews.llvm.org/D49191

llvm-svn: 336907
2018-07-12 14:36:48 +00:00
Vedant Kumar ba0c876597 [Debugify] Allow unsigned values narrower than their variables
Suppress the diagnostic for mis-sized dbg.values when a value operand is
narrower than the unsigned variable it describes. Assume that a debugger
would implicitly zero-extend these values.

llvm-svn: 336452
2018-07-06 17:32:40 +00:00
Gabor Buella da4a966e1c NFC - Various typo fixes in tests
llvm-svn: 336268
2018-07-04 13:28:39 +00:00
Shiva Chen a0a52bf195 [DebugInfo] Fix PR37395.
DbgLabelInst has no address as its operands.

Differential Revision: https://reviews.llvm.org/D46738

Patch by Hsiangkai Wang.

llvm-svn: 336176
2018-07-03 07:56:04 +00:00
Vedant Kumar 9b6c096fb5 Tighten up a test for -check-debugify, NFC
Use an -implicit-check-not to make sure an error which should not occur
in fact does not occur before the first CHECK line.

Suggested by Paul Robinson in post-commit feedback for r335897.

llvm-svn: 336123
2018-07-02 17:08:36 +00:00
Yaron Keren d414c6c131 Disable failing test on x86_64-pc-windows-gnu, see PR38006.
llvm-svn: 336110
2018-07-02 14:39:32 +00:00
Alexey Bataev 2a03d4296a [DEBUG_INFO, NVPTX] Do not emit .debug_loc section.
Summary:
.debug_loc section is not supported for NVPTX target. If there is an
object whose location can change during its lifetime, we do not generate
debug location info for this variable.

Reviewers: echristo

Subscribers: jholewinski, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D48730

llvm-svn: 335976
2018-06-29 14:23:28 +00:00
Jessica Paquette 0c5d3ffbb8 [MachineOutliner] Never add the outliner in -O0
This is a recommit of r335879.

We shouldn't add the outliner when compiling at -O0 even if
-enable-machine-outliner is passed in. This makes sure that we
don't add it in this case.

This also removes -O0 from the outliner DWARF test.

llvm-svn: 335930
2018-06-28 21:49:24 +00:00
Vedant Kumar 197e73fede [Debugify] Do not report line 0 locations as errors
The checking logic should not treat artificial locations as being
somehow problematic. Producing these locations can be the desired
behavior of some passes.

See llvm.org/PR37961.

llvm-svn: 335897
2018-06-28 18:21:11 +00:00
Alexey Bataev 5f6e51d54c [DEBUG_INFO, NVPTX] Add test for .debug_loc section, NFC.
llvm-svn: 335861
2018-06-28 15:14:58 +00:00
Vedant Kumar b9c1a234d2 [Debugify] Diagnose mis-sized dbg.values
Report an error in -check-debugify when the size of a dbg.value operand
doesn't match up with the size of the variable it describes.

Eventually this check should be moved into the IR verifier. For the
moment, it's useful to include the check in -check-debugify as a means
of catching regressions and finding existing bugs.

Here are some instances of bugs the new check finds in the -O2 pipeline
(all in InstCombine):

1) A float is used where a double is expected:

ERROR: dbg.value operand has size 32, but its variable has size 64:
call void @llvm.dbg.value(metadata float %expf, metadata !12, metadata
!DIExpression()), !dbg !15

2) An i8 is used where an i32 is expected:

ERROR: dbg.value operand has size 8, but its variable has size 32:
call void @llvm.dbg.value(metadata i8 %t4, metadata !14, metadata
!DIExpression()), !dbg !24

3) A <4 x i32> is used where something twice as large is expected
(perhaps a <4 x i64>, I haven't double-checked):

ERROR: dbg.value operand has size 128, but its variable has size 256:
call void @llvm.dbg.value(metadata <4 x i32> %4, metadata !40, metadata
!DIExpression()), !dbg !95

Differential Revision: https://reviews.llvm.org/D48408

llvm-svn: 335682
2018-06-26 22:46:41 +00:00
Vedant Kumar 2e6c5f96dc [Debugify] Don't treat missing dbg.values as an error (PR37942)
When checking the debug info in a module, don't treat a missing
dbg.value as an error. The dbg.value may simply have been DCE'd, in
which case the debugger has enough information to display the variable
as <optimized out>.

llvm-svn: 335647
2018-06-26 18:54:10 +00:00
Vedant Kumar b725c69f12 [SelectionDAG] Remove debug locations from ConstantSD(FP)Nodes
This removes debug locations from ConstantSDNode and ConstantSDFPNode.

When this kind of node is materialized we no longer create a line table
entry which jumps back to the constant's first point of use. This makes
single-stepping behavior smoother, and it matches the model used by IR,
where Constants have no locations. See this thread for more context:

  http://lists.llvm.org/pipermail/llvm-dev/2018-June/124164.html

I'd like to handle constant BuildVectorSDNodes and to try to eliminate
passing SDLocs to SelectionDAG::getConstant*() in follow-up commits.

Differential Revision: https://reviews.llvm.org/D48468

llvm-svn: 335497
2018-06-25 17:06:18 +00:00
Mikael Holmen 42f7bc96dd [DebugInfo] Make sure all DBG_VALUEs' reguse operands have IsDebug property
Summary:
In some cases, these operands lacked the IsDebug property, which is meant to signal that
they should not affect codegen. This patch adds a check for this property in the
MachineVerifier and adds it where it was missing.

This includes refactorings to use MachineInstrBuilder construction functions instead of
manually setting up the intrinsic everywhere.

Patch by: JesperAntonsson

Reviewers: aprantl, rnk, echristo, javed.absar

Reviewed By: aprantl

Subscribers: qcolombet, sdardis, nemanjai, JDevlieghere, atanasyan, llvm-commits

Differential Revision: https://reviews.llvm.org/D48319

llvm-svn: 335214
2018-06-21 10:03:34 +00:00
Mikael Holmen 57b33f6aac [DebugInfo] Keep DBG_VALUE undef in LiveDebugVariables
Summary:
Fixes PR36579.

For cases where we had e.g.

 DBG_VALUE 42
 [...]
 DBG_VALUE undef

LiveDebugVariables would discard all undef DBG_VALUEs and then it would
look like the variable had the value 42 throughout the rest of the
function, which is incorrect.

With this patch we don't remove all undef DBG_VALUEs in LiveDebugVariables
so they will be kept after register allocation just like other DBG_VALUEs
which will yield more correct debug information.

Reviewers: aprantl

Reviewed By: aprantl

Subscribers: bjope, Ka-Ka, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D48277

llvm-svn: 335205
2018-06-21 07:02:46 +00:00
Wolfgang Pieb 61d8c8d9b3 [DWARF] Improved error reporting for range lists.
Errors found processing the DW_AT_ranges attribute are propagated by lower level 
routines and reported by their callers.

Reviewer: JDevlieghere

Differential Revision: https://reviews.llvm.org/D48344

llvm-svn: 335188
2018-06-20 22:56:37 +00:00
Alina Sbirlea dfd14adeb0 Generalize MergeBlockIntoPredecessor. Replace uses of MergeBasicBlockIntoOnlyPred.
Summary:
Two utils methods have essentially the same functionality. This is an attempt to merge them into one.
1. lib/Transforms/Utils/Local.cpp : MergeBasicBlockIntoOnlyPred
2. lib/Transforms/Utils/BasicBlockUtils.cpp : MergeBlockIntoPredecessor

Prior to the patch:
1. MergeBasicBlockIntoOnlyPred
Updates either DomTree or DeferredDominance
Moves all instructions from Pred to BB, deletes Pred
Asserts BB has single predecessor
If address was taken, replace the block address with constant 1 (?)

2. MergeBlockIntoPredecessor
Updates DomTree, LoopInfo and MemoryDependenceResults
Moves all instruction from BB to Pred, deletes BB
Returns if doesn't have a single predecessor
Returns if BB's address was taken

After the patch:
Method 2. MergeBlockIntoPredecessor is attempting to become the new default:
Updates DomTree or DeferredDominance, and LoopInfo and MemoryDependenceResults
Moves all instruction from BB to Pred, deletes BB
Returns if doesn't have a single predecessor
Returns if BB's address was taken

Uses of MergeBasicBlockIntoOnlyPred that need to be replaced:

1. lib/Transforms/Scalar/LoopSimplifyCFG.cpp
Updated in this patch. No challenges.

2. lib/CodeGen/CodeGenPrepare.cpp
Updated in this patch.
  i. eliminateFallThrough is straightforward, but I added using a temporary array to avoid the iterator invalidation.
  ii. eliminateMostlyEmptyBlock(s) methods also now use a temporary array for blocks
Some interesting aspects:
  - Since Pred is not deleted (BB is), the entry block does not need updating.
  - The entry block was being updated with the deleted block in eliminateMostlyEmptyBlock. Added assert to make obvious that BB=SinglePred.
  - isMergingEmptyBlockProfitable assumes BB is the one to be deleted.
  - eliminateMostlyEmptyBlock(BB) does not delete BB on one path, it deletes its unique predecessor instead.
  - adding some test owner as subscribers for the interesting tests modified:
    test/CodeGen/X86/avx-cmp.ll
    test/CodeGen/AMDGPU/nested-loop-conditions.ll
    test/CodeGen/AMDGPU/si-annotate-cf.ll
    test/CodeGen/X86/hoist-spill.ll
    test/CodeGen/X86/2006-11-17-IllegalMove.ll

3. lib/Transforms/Scalar/JumpThreading.cpp
Not covered in this patch. It is the only use case using the DeferredDominance.
I would defer to Brian Rzycki to make this replacement.

Reviewers: chandlerc, spatel, davide, brzycki, bkramer, javed.absar

Subscribers: qcolombet, sanjoy, nemanjai, nhaehnle, jlebar, tpr, kbarton, RKSimon, wmi, arsenm, llvm-commits

Differential Revision: https://reviews.llvm.org/D48202

llvm-svn: 335183
2018-06-20 22:01:04 +00:00
Jessica Paquette 6f78be66e6 [MachineOutliner] Add debug info test for the outliner
The outliner emits debug info. Add a test that outlines a function
and uses llvm-dwarfdump to check the emitted DWARF for correctness.

llvm-svn: 335153
2018-06-20 18:41:11 +00:00
Bjorn Pettersson 428caf988b Re-apply "[DebugInfo] Check size of variable in ConvertDebugDeclareToDebugValue"
This is r334704 (which was reverted in r334732) with a fix for
types like x86_fp80. We need to use getTypeAllocSizeInBits and
not getTypeStoreSizeInBits to avoid dropping debug info for
such types.

Original commit msg:
> Summary:
> Do not convert a DbgDeclare to DbgValue if the store
> instruction only refer to a fragment of the variable
> described by the DbgDeclare.
>
> Problem was seen when for example having an alloca for an
> array or struct, and there were stores to individual elements.
> In the past we inserted a DbgValue intrinsics for each store,
> just as if the store wrote the whole variable.
>
> When handling store instructions we insert a DbgValue that
> indicates that the variable is "undefined", as we do not know
> which part of the variable that is updated by the store.
>
> When ConvertDebugDeclareToDebugValue is used with a load/phi
> instruction we assert that the referenced value is large enough
> to cover the whole variable. Afaict this should be true for all
> scenarios where those methods are used on trunk. If the assert
> blows in the future I guess we could simply skip to insert a
> dbg.value instruction.
>
> In the future I think we should examine which part of the variable
> that is accessed, and add a DbgValue instrinsic with an appropriate
> DW_OP_LLVM_fragment expression.
>
> Reviewers: dblaikie, aprantl, rnk
>
> Reviewed By: aprantl
>
> Subscribers: JDevlieghere, llvm-commits
>
> Tags: #debug-info
>
> Differential Revision: https://reviews.llvm.org/D48024

llvm-svn: 334830
2018-06-15 13:48:55 +00:00
Brock Wyma b60532f89a [CodeView] Omit forward references for unnamed structs and unions
Codeview references to unnamed structs and unions are expected to refer to the
complete type definition instead of a forward reference so Visual Studio can
resolve the type properly.

Differential Revision: https://reviews.llvm.org/D32498

llvm-svn: 334382
2018-06-11 01:39:34 +00:00
Vedant Kumar a9e27312b8 [Debugify] Add a quiet mode to suppress warnings
Suppressing warning output and module dumps significantly speeds up
fuzzing with `opt -debugify-each`.

llvm-svn: 334117
2018-06-06 19:05:41 +00:00
Vedant Kumar b6ed992de0 [opt] Introduce -strip-named-metadata
This renames and generalizes -strip-module-flags to erase all named
metadata from a module. This makes it easier to diff IR.

llvm-svn: 333977
2018-06-05 00:56:08 +00:00
Vedant Kumar fb7c768a3b [Debugify] Preserve analyses in -check-debugify
The -check-debugify pass should preserve all analyses. Otherwise, it may
invalidate an optional analysis and inadvertently alter codegen.

The test case is reduced from deopt-bundle.ll. The result of `opt -O1`
on this file would differ when -debugify-each was toggled. That happened
because CheckDebugify failed to preserve GlobalsAA.

Thanks to Davide Italiano for his help chasing this down!

llvm-svn: 333959
2018-06-04 21:43:28 +00:00
Vedant Kumar adbd27a599 [Debugify] Don't apply DI before the bitcode writer pass
Applying synthetic debug info before the bitcode writer pass has no
testing-related purpose. This commit prevents that from happening.

It also adds tests which check that IR produced with/without
-debugify-each enabled is identical after stripping. This makes it
possible to check that individual passes (or full pipelines) are
invariant to debug info.

llvm-svn: 333861
2018-06-04 00:11:49 +00:00
Vedant Kumar f0e4321c30 [opt] Add a -strip-module-flags option
The -strip-module-flags option strips llvm.module.flags metadata from a
module at the beginning of the opt pipeline.

This will be used to test whether the output of a pass is debug info
(DI) invariant.

E.g, after applying synthetic debug info to a test case, we'd like to
strip out all DI-related metadata and check that the final IR is
identical to a baseline file without any DI applied, to check that
optimizations aren't inhibited by debug info.

llvm-svn: 333860
2018-06-04 00:11:48 +00:00
Vedant Kumar 77f4d4d8aa [Debugify] Skip dbg.value placement for EH pads, musttail
Placing meta-instructions into EH pads breaks certain IR invariants, as
does placing instructions after a musttail call.

llvm-svn: 333856
2018-06-03 22:50:22 +00:00
Vedant Kumar 4a2798c934 Remove the test from r333801
In r333801 I added a test for a dump method that, for reasons I don't
understand, fails on an msvc bot:

http://lab.llvm.org:8011/builders/clang-x86-windows-msvc2015/builds/12306/

I'll remove the test for now to unblock the bot and try to look into why
there's a discrepancy on this platform later.

llvm-svn: 333807
2018-06-02 00:05:17 +00:00
Vedant Kumar 7224c08141 Add a debug dump for DbgValueHistoryMap
This makes it easier to inspect the results of
DbgValueHistoryCalculator.

Differential Revision: https://reviews.llvm.org/D47663

llvm-svn: 333801
2018-06-01 22:33:15 +00:00
Daniel Cederman d72b9fd141 Implemented sane default for llvm-objdump's relocation Value format
Summary:
"Unknown" for platforms that were not manually added into the switch
did not make sense at all. Now it prints Target + addend for all
elf-machines that were not explicitly mentioned.

Addresses PR21059 and PR25124.

Original author: fedor.sergeev

Reviewers: jyknight, espindola, fedor.sergeev

Reviewed By: jyknight

Subscribers: eraman, dcederman, jfb, dschuff, aheejin, llvm-commits

Differential Revision: https://reviews.llvm.org/D36464

llvm-svn: 333726
2018-06-01 05:31:58 +00:00
Douglas Yung 99feb567bf Update CodeView register names in a test that was missed in r333421.
llvm-svn: 333453
2018-05-29 19:21:22 +00:00
Jonas Devlieghere 43dce3edbe [CodeView] Add prefix to CodeView registers.
Adds CVReg to CodeView register names to prevent a duplicate symbol with
CR3 defined in termios.h, as suggested by Zachary on the mailing list.

http://lists.llvm.org/pipermail/llvm-dev/2018-May/123372.html

Differential revision: https://reviews.llvm.org/D47478

rdar://39863705

llvm-svn: 333421
2018-05-29 14:35:34 +00:00
Vedant Kumar 4872535eb9 [Debugify] Set a DI version module flag for llc compatibility
Setting the "Debug Info Version" module flag makes it possible to pipe
synthetic debug info into llc, which is useful for testing backends.

llvm-svn: 333237
2018-05-24 23:00:23 +00:00
Vedant Kumar b70e35686b [Debugify] Avoid printing unnecessary square braces, NFC
llvm-svn: 333236
2018-05-24 23:00:22 +00:00
Vedant Kumar 40399a213d [DebugInfo] Maintain DI when converting GEP to bitcast
When a GEP with all zero indices is converted to bitcast, its DI wasn't
copied over to the newly created instruction. This patch fixes that bug.

Patch by Kareem Ergawy!

Differential Revision: https://reviews.llvm.org/D47347

llvm-svn: 333235
2018-05-24 23:00:21 +00:00
Vedant Kumar 7417789317 Move a debug info test into the X86 directory
This test triggers a code path which does not appear to fire on some
targets:

http://lab.llvm.org:8011/builders/clang-cmake-armv8-quick/builds/3028

I've made the test X86-specific in an attempt to address the issue.

llvm-svn: 333138
2018-05-23 22:50:45 +00:00
Vedant Kumar 9374c0432b [DebugInfo] Maintain DI for sunken bitcasts
When a bitcast is being sunk in -codegenprepare pass, its DI wasn't
copied over to the newly created instruction. This patch fixes that
bug.

Patch by Kareem Ergawy!

Differential Revision: https://reviews.llvm.org/D47282

llvm-svn: 333133
2018-05-23 22:03:48 +00:00
Paul Robinson 543c0e1d50 [DWARFv5] Put the DWO ID in its place.
In DWARF v5, the DWO ID is in the (split/skeleton) CU header, not an
attribute on the CU DIE.

This changes the size of those headers, so use the parsed size whenever
we have one, for simplicitly.

Differential Revision: https://reviews.llvm.org/D47158

llvm-svn: 333004
2018-05-22 17:27:31 +00:00
Brian Gesiak a398590f56 [DebugInfo] Fix typo "DWARG" in test comment (NFC)
Summary:
The correct spelling is "DWARF", the debugging format, not "DWARG".
The typo is in a (not executed by lit) comment in a test file, so
fixing it does not result in any functional change.

Test Plan: check-llvm, just in case

llvm-svn: 332878
2018-05-21 19:48:27 +00:00
Jonas Devlieghere c111382aa8 [DebugInfo] Use absolute addresses in location lists
Rather than relying on the user to do the address calculating in
DW_AT_location we should just dump the absolute address.

rdar://problem/38513870

Differential revision: https://reviews.llvm.org/D47152

llvm-svn: 332873
2018-05-21 19:36:54 +00:00
Nico Weber d418776e04 win: try more to fix dia tests with newer msvc versions
llvm-svn: 332828
2018-05-21 02:55:41 +00:00
Nico Weber da5513b9c4 win: try to fix dia tests with newer msvc versions
llvm-svn: 332827
2018-05-21 02:09:57 +00:00
Wolfgang Pieb ad60559be7 [DWARF v5] Improved support for .debug_rnglists (consumer). Enables any consumer to
extract DWARF v5 encoded rangelists.

Reviewer: JDevlieghere

Differential Revision: https://reviews.llvm.org/D45549

llvm-svn: 332759
2018-05-18 20:12:54 +00:00
Eric Christopher 68f2218e1e Revert "Temporarily revert "[DEBUG] Initial adaptation of NVPTX target for debug info emission.""
This reapplies commits: r330271, r330592, r330779.

    [DEBUG] Initial adaptation of NVPTX target for debug info emission.

    Summary:
    Patch adds initial emission of the debug info for NVPTX target.
    Currently, only .file and .loc directives are emitted, everything else is
    commented out to not break the compilation of Cuda.

llvm-svn: 332689
2018-05-18 03:13:08 +00:00
Zachary Turner c762666e87 Resubmit [pdb] Change /DEBUG:GHASH to emit 8 byte hashes."
This fixes the remaining failing tests, so resubmitting with no
functional change.

llvm-svn: 332676
2018-05-17 22:55:15 +00:00
Zachary Turner 1de9fce151 Revert "[pdb] Change /DEBUG:GHASH to emit 8 byte hashes."
A few tests haven't been properly updated, so reverting while
I have time to investigate proper fixes.

llvm-svn: 332672
2018-05-17 21:49:25 +00:00
Zachary Turner 3c4c8a0937 [pdb] Change /DEBUG:GHASH to emit 8 byte hashes.
Previously we emitted 20-byte SHA1 hashes.  This is overkill
for identifying debug info records, and has the negative side
effect of making object files bigger and links slower.  By
using only the last 8 bytes of a SHA1, we get smaller object
files and ~10% faster links.

This modifies the format of the .debug$H section by adding a new
value for the hash algorithm field, so that the linker will still
work when its object files have an old format.

Differential Revision: https://reviews.llvm.org/D46855

llvm-svn: 332669
2018-05-17 21:22:48 +00:00
Reid Kleckner f40f85868e [codeview] Include record prefix in global type hashing
The prefix includes type kind, which is important to preserve. Two
different type leafs can easily have the same interior record contents
as another type.

We ran into this issue in PR37492 where a bitfield type record collided
with a const modifier record. Their contents were bitwise identical, but
their kinds were different.

llvm-svn: 332664
2018-05-17 20:47:22 +00:00
Anastasis Grammenos d6c6678766 [Debugify] Print the output to stderr
Currently debugify prints it's output to stdout,
with this patch all the output generated goes to stderr.

This change lets us use debugify without taking away
the ability to pipe the output to other llvm tools.

llvm-svn: 332642
2018-05-17 18:19:58 +00:00
Vedant Kumar 5c6b3fb8fb [Debugify] Tighten up the test for -debugify-each, NFC
In post-commit review for r332416, Paul Robinson pointed out that the
test for -debugify-each is not checking what it needs to.

This commit tightens up the test.

llvm-svn: 332497
2018-05-16 17:30:58 +00:00
Anastasis Grammenos b4344c66aa [Debugfiy] Print the pass name next to the result
CheckDebugify now prints the pass name right next to the result of the check.

Differential Revision: https://reviews.llvm.org/D46908

llvm-svn: 332416
2018-05-15 23:38:05 +00:00
Vedant Kumar 595ba1d548 [Debugify] Add -debugify-each for testing each pass in a pipeline
This adds a -debugify-each mode to opt which, when enabled, wraps each
{Module,Function}Pass in a pipeline with logic to add, check, and strip
synthetic debug info for testing purposes.

This mode can be used to test complex pipelines for debug info bugs, or
to collect statistics about the number of debug values & locations lost
throughout various stages of a pipeline.

Patch by Son Tuan Vu!

Differential Revision: https://reviews.llvm.org/D46525

llvm-svn: 332312
2018-05-15 00:29:27 +00:00
Brock Wyma 3db2b108c3 [CodeView] Improve debugging of virtual base class member variables
Initial support for passing the virtual base pointer offset to CodeViewDebug.

https://reviews.llvm.org/D46271

llvm-svn: 332296
2018-05-14 21:21:22 +00:00
Pavel Labath 2a6afe5f87 [CodeGen/AccelTable]: Handle -dwarf-linkage-names=Abstract correctly
Summary:
If we are not emitting a linkage name in the .debug_info sections, we
should not add it into the index either. This makes sure our index is
consistent with the actual debug info.

I am also explicitly setting the --dwarf-linkage-names=All in the
name-collsions test as that one would now fail on targets where this
defaults to "Abstract" (in fact, it would have failed already if there
wasn't a bug in the DWARF verifier, which I fix as well).

Reviewers: probinson, aprantl, JDevlieghere

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D46748

llvm-svn: 332246
2018-05-14 14:13:20 +00:00
Wolfgang Pieb f2b6915ed4 [DWARF] Fixing a bug in DWARF v5 string offsets tables where the length encoded the contribution
length excluding the table header. Instead it must encode the contribution length minus the length
field itself.

Reviewer: JDevliegehere

Differential Revision: https://reviews.llvm.org/D45922

llvm-svn: 332030
2018-05-10 20:02:34 +00:00
Sam Clegg a5908009cd [WebAsembly] Update default triple in test files to wasm32-unknown-unkown.
Summary: The final -wasm component has been the default for some time now.

Subscribers: jfb, dschuff, jgravelle-google, eraman, aheejin, JDevlieghere, sunfish, llvm-commits

Differential Revision: https://reviews.llvm.org/D46342

llvm-svn: 332007
2018-05-10 17:49:11 +00:00
James Henderson a3acf99e59 [DWARF] Rework debug line parsing to use llvm::Error and callbacks
Reviewed by: dblaikie, JDevlieghere, espindola

Differential Revision: https://reviews.llvm.org/D44560

Summary:
The .debug_line parser previously reported errors by printing to stderr and
return false. This is not particularly helpful for clients of the library code,
as it prevents them from handling the errors in a manner based on the calling
context. This change switches to using llvm::Error and callbacks to indicate
what problems were detected during parsing, and has updated clients to handle
the errors in a location-specific manner. In general, this means that they
continue to do the same thing to external users. Below, I have outlined what
the known behaviour changes are, relating to this change.

There are two levels of "errors" in the new error mechanism, to broadly
distinguish between different fail states of the parser, since not every
failure will prevent parsing of the unit, or of subsequent unit. Malformed
table errors that prevent reading the remainder of the table (reported by
returning them) and other minor issues representing problems with parsing that
do not prevent attempting to continue reading the table (reported by calling a
specified callback funciton). The only example of this currently is when the
last sequence of a unit is unterminated. However, I think it would be good to
change the handling of unrecognised opcodes to report as minor issues as well,
rather than just printing to the stream if --verbose is used (this would be a
subsequent change however).

I have substantially extended the DwarfGenerator to be able to handle
custom-crafted .debug_line sections, allowing for comprehensive unit-testing
of the parser code. For now, I am just adding unit tests to cover the basic
error reporting, and positive cases, and do not currently intend to test every
part of the parser, although the framework should be sufficient to do so at a
later point.

Known behaviour changes:
  - The dump function in DWARFContext now does not attempt to read subsequent
  tables when searching for a specific offset, if the unit length field of a
  table before the specified offset is a reserved value.
  - getOrParseLineTable now returns a useful Error if an invalid offset is
  encountered, rather than simply a nullptr.
  - The parse functions no longer use `WithColor::warning` directly to report
  errors, allowing LLD to call its own warning function.
  - The existing parse error messages have been updated to not specifically
  include "warning" in their message, allowing consumers to determine what
  severity the problem is.
  - If the line table version field appears to have a value less than 2, an
  informative error is returned, instead of just false.
  - If the line table unit length field uses a reserved value, an informative
  error is returned, instead of just false.
  - Dumping of .debug_line.dwo sections is now implemented the same as regular
  .debug_line sections.
  - Verbose dumping of .debug_line[.dwo] sections now prints the prologue, if
  there is a prologue error, just like non-verbose dumping.

As a helper for the generator code, I have re-added emitInt64 to the
AsmPrinter code. This previously existed, but was removed way back in r100296,
presumably because it was dead at the time.

This change also requires a change to LLD, which will be committed separately.

llvm-svn: 331971
2018-05-10 10:51:33 +00:00
Benjamin Kramer 7b307bced3 [DebugInfo] Mark tests using -debug-only as REQUIRES: asserts
llvm-svn: 331865
2018-05-09 11:17:30 +00:00
Shiva Chen 39a694ffe4 [DebugInfo] Fix test failed due to debug-label-mi.ll and debug-label-opt.ll
Make these two test cases more generic for other architectures.
Please refer to '[DebugInfo] Convert intrinsic llvm.dbg.label to
MachineInstr.'

Patch by Hsiangkai Wang

llvm-svn: 331853
2018-05-09 07:09:28 +00:00
Shiva Chen 196b28a97a [DebugInfo] Fix test failed due to new DISubprogram attributes.
Please refer to '[DebugInfo] Add DILabel metadata and intrinsic
llvm.dbg.label'. I have renamed the 'variables' attributes to
'retainedNodes' to include local variables and local labels for the
function.

Patch by Hsiangkai Wang.

llvm-svn: 331848
2018-05-09 06:22:39 +00:00
Shiva Chen cd070cdc94 [DebugInfo] Convert intrinsic llvm.dbg.label to MachineInstr.
In order to convert LLVM IR to MachineInstr, we need a new TargetOpcode,
DBG_LABEL, to ‘lower’ intrinsic llvm.dbg.label. The patch
creates this new TargetOpcode and convert intrinsic llvm.dbg.label to
MachineInstr through SelectionDAG.

In SelectionDAG, debug information is stored in SDDbgInfo. We create a
new data member of SDDbgInfo for labels and use the new data member,
SDDbgLabel, to create DBG_LABEL MachineInstr.

The new DBG_LABEL MachineInstr uses label metadata from LLVM IR as its
parameter. So, the backend could get metadata information of labels from
DBG_LABEL MachineInstr.

Differential Revision: https://reviews.llvm.org/D45341

Patch by Hsiangkai Wang.

llvm-svn: 331842
2018-05-09 02:41:08 +00:00
Shiva Chen 2c864551df [DebugInfo] Add DILabel metadata and intrinsic llvm.dbg.label.
In order to set breakpoints on labels and list source code around
labels, we need collect debug information for labels, i.e., label
name, the function label belong, line number in the file, and the
address label located. In order to keep these information in LLVM
IR and to allow backend to generate debug information correctly.
We create a new kind of metadata for labels, DILabel. The format
of DILabel is

!DILabel(scope: !1, name: "foo", file: !2, line: 3)

We hope to keep debug information as much as possible even the
code is optimized. So, we create a new kind of intrinsic for label
metadata to avoid the metadata is eliminated with basic block.
The intrinsic will keep existing if we keep it from optimized out.
The format of the intrinsic is

llvm.dbg.label(metadata !1)

It has only one argument, that is the DILabel metadata. The
intrinsic will follow the label immediately. Backend could get the
label metadata through the intrinsic's parameter.

We also create DIBuilder API for labels to be used by Frontend.
Frontend could use createLabel() to allocate DILabel objects, and use
insertLabel() to insert llvm.dbg.label intrinsic in LLVM IR.

Differential Revision: https://reviews.llvm.org/D45024

Patch by Hsiangkai Wang.

llvm-svn: 331841
2018-05-09 02:40:45 +00:00