Commit Graph

227 Commits

Author SHA1 Message Date
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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 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
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
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
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 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
Pavel Labath 10831f594a Fix macosx build broken by r330249
It seems llc crashes when targetting darwin with split-dwarf (pr37164).
This happens on all inputs, not just the one I added in the above
commit. Work around the issue by hardcoding the target triple to linux,
which is what all split-dwarf tests seem to be doing.

As I don't know of a way to specify the os part of the triple without
spelling out the architecture as well, I move the new test to the X86
folder.

llvm-svn: 330265
2018-04-18 15:23:21 +00:00
Pavel Labath 3fb39c79ed [CodeGen/Dwarf] Make debug_names compatible with split-dwarf
Summary:
Previously we crashed for the combination of the two features because we
tried to reference the dwo CU from the main object file. The fix
consists of two items:
- reference the skeleton CU from the name index (the consumer is
  expected to use the skeleton CU to find the real data).
- use the main object file string pool for the strings in the index

Reviewers: JDevlieghere, aprantl, dblaikie

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45566

llvm-svn: 330249
2018-04-18 12:11:59 +00:00
Roman Tereshin 7a44782c73 [DebugInfo] Follow-up bug fix on "Fixing a couple of DI duplication bugs of CloneModule"
Apparently, DebugInfoFinder::processCompileUnit doesn't process all
of the possible kinds of DIImportedEntit'ies, e.g. DIGlobalVariable's.

Previously introduced `llvm_unreachable` is therefore incorrect.
Removing it here.

llvm-svn: 330167
2018-04-16 23:39:44 +00:00
Vedant Kumar 65b0d4df20 [DebugInfo] Create merged locations for instructions other than calls
This lifts a restriction on DILocation::getMergedLocation(), allowing it
to create merged locations for instructions other than calls.

Instruction::applyMergedLocation() now defaults to creating merged
locations for all instructions.

The default behavior of getMergedLocation() is unchanged: callers which
invoke it directly are unaffected.

This change will enable a follow-up Mem2Reg fix which improves crash
reporting.

Differential Revision: https://reviews.llvm.org/D45396

llvm-svn: 329955
2018-04-12 20:58:24 +00:00
Pavel Labath b7243ed2f4 [CodeGen/Dwarf] Rename the "sizetype" synthetic type and add it to the accelerator table
Summary:
This type is created on-demand and used as the base type for array
ranges. Since it is "special", its construction did not go through the
createTypeDIE function and so it was never inserted into the accelerator
table, although it clearly belongs there.

I add an explicit addAccelType call to insert it into the table.

During review, we also decided to rename the type to something more
unique to avoid confusion in case the user has own "sizetype" type. The
new name for the type size __ARRAY_SIZE_TYPE__.

Reviewers: JDevlieghere, aprantl, dblaikie

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45445

llvm-svn: 329705
2018-04-10 14:23:41 +00:00
Pavel Labath eadfac8748 [CodeGen/AccelTable] Don't emit zero-CU name indexes
Summary:
If an input DICompileUnit is completely empty (e.g., the result of
running "clang -g" on an empty file), we don't bother emitting an empty
DWARF CU. When we do that, we must make sure we don't also emit a DWARF v5
name index, as DWARF specifies that each index must reference at least
one compilation unit.

Reviewers: JDevlieghere, aprantl, dblaikie

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45435

llvm-svn: 329575
2018-04-09 14:38:53 +00:00
Pavel Labath b1b2f40556 Make the test case from r329552 more portable
- when tuning for SCE debugger (default for ps4 targets), we will not emit
  the DW_AT_linkage_name, which this test needs. I explicitly set the
  debugger tuning parameter to get the attribute always.
- darwin targets did not like the "section .text.startup" fragment of
  the test. This is not actually needed for the test, so I remove it.

llvm-svn: 329555
2018-04-09 09:11:40 +00:00
Pavel Labath 889bf9fe00 [CodeGen/AccelTable]: Don't emit accelerator entries for functions with no names
Summary:
We were emitting accelerator entries for functions with no name, which
is contrary to the DWARF v5 spec: "All other (i.e., *not*
DW_TAG_namespace) debugging information entries without a DW_AT_name
attribute are excluded." Besides that, a name table entry with an empty
string as a key is fairly useless.

We can sometimes end up with functions which have a DW_AT_linkage_name but no
DW_AT_name. One such example is the global-constructor-initialization functions,
which C++ compilers synthesize for each compilation unit with global
constructors.
A very strict reading of the DWARF v5 spec would suggest that we should not even
emit the accelerator entry for the linkage name in this case, but I don't think
we should go that far.

I found this when running the dwarf verifier over llvm codebase compiled
with DWARF v5 accelerator tables.

Reviewers: JDevlieghere, aprantl, dblaikie

Subscribers: vleschuk, clayborg, echristo, probinson, llvm-commits

Differential Revision: https://reviews.llvm.org/D45367

llvm-svn: 329552
2018-04-09 08:41:57 +00:00
Pavel Labath 6088c23431 Re-commit r329179 after fixing build&test issues
- MSVC was not OK with a static_assert referencing a non-static member
  variable, even though it was just in a sizeof(expression). I move the
  assert into the emit function, where it is probably more useful.
- Tests were failing in builds which did not have the X86 target
  configured. Since this functionality is not target-specific, I have
  removed the target specifiers from the .ll files.

llvm-svn: 329201
2018-04-04 14:42:14 +00:00
Nico Weber 55fcd07d25 Revert r329179 (and follow-up unsuccessful fix attempts 329184, 329186); it doesn't build.
llvm-svn: 329190
2018-04-04 13:06:22 +00:00
Pavel Labath 69baab103a [CodeGen] Generate DWARF v5 Accelerator Tables
Summary:
This patch adds a DwarfAccelTableEmitter class, which generates an
accelerator table, as specified in DWARF v5 standard. At the moment it
only generates a DIE offset column and (if we are indexing more than one
compile unit) a CU column.

Indexing type units is not currently supported, as we don't even have
the ability to generate DWARF v5-compatible compile units.

The implementation is not data-source agnostic like the one generating
apple tables. This was not necessary as we currently only have one user
of this code, and without a second user it was not obvious to me how to
best abstract this. (The difference between these tables and the apple
ones is that they need a lot more metadata about the debug info they are
indexing).

The generation is triggered by the --accel-tables argument, which
supersedes the --dwarf-accel-tables arg -- the latter was a simple
on-off switch, but not we can choose between two kinds of accelerator
tables we can generate.

This is tested by parsing the generated tables with llvm-dwarfdump and
the DWARFVerifier, and I've also checked that GNU readelf is able to
make sense of the tables.

Differential Revision: https://reviews.llvm.org/D43286

llvm-svn: 329179
2018-04-04 12:28:20 +00:00
Alexey Bataev f7226ed67d [DEBUGINFO] Add option that allows to disable emission of flags in .loc directives.
Summary:
Some targets do not support extended format of .loc directive and
support only simple format: .loc <FileID> <Line> <Column>. Patch adds
MCAsmInfo flag and option that allows emit .loc directive without
additional flags.

Reviewers: echristo

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45184

llvm-svn: 329089
2018-04-03 17:28:55 +00:00
Adrian Prantl 3e4a82ffa2 Move generic test to the Generic directory
llvm-svn: 327148
2018-03-09 16:42:05 +00:00
Adrian Prantl 5b477be72a LowerDbgDeclare: ignore dbg.declares for allocas with volatile access
There is no point in lowering a dbg.declare describing an alloca that
has volatile loads or stores as users, since the alloca cannot be
elided. Lowering the dbg.declare will result in larger debug info that
may also have worse coverage than just describing the alloca.

rdar://problem/34496278

llvm-svn: 327092
2018-03-09 00:45:04 +00:00
Paul Robinson 1e0116c91d [DWARF] Emit a split line table only if there are split type units.
A .debug_info.dwo section doesn't use the .debug_line.dwo section.

llvm-svn: 326395
2018-03-01 00:12:35 +00:00
Scott Linder 16c7bdaf32 [DebugInfo] Support DWARF v5 source code embedding extension
In DWARF v5 the Line Number Program Header is extensible, allowing values with
new content types. In this extension a content type is added,
DW_LNCT_LLVM_source, which contains the embedded source code of the file.

Add new optional attribute for !DIFile IR metadata called source which contains
source text. Use this to output the source to the DWARF line table of code
objects. Analogously extend METADATA_FILE in Bitcode and .file directive in ASM
to support optional source.

Teach llvm-dwarfdump and llvm-objdump about the new values. Update the output
format of llvm-dwarfdump to make room for the new attribute on file_names
entries, and support embedded sources for the -source option in llvm-objdump.

Differential Revision: https://reviews.llvm.org/D42765

llvm-svn: 325970
2018-02-23 23:01:06 +00:00
Alexey Bataev 0d6aeadc40 [DEBUGINFO] Add support for emission of the inlined strings.
Summary:
Patch adds an option for emission of inlined strings rather than
.debug_str section.

Reviewers: echristo, jlebar

Subscribers: eraman, llvm-commits, JDevlieghere

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

llvm-svn: 325583
2018-02-20 15:28:08 +00:00
Sander de Smalen bf83be9e2a [DebugInfo] Removed assert on missing CountVarDIE
Summary:
The assert for a DISubrange's CountVarDIE to be available fails
when the dbg.value() has been optimized away for any reason.
Having the assert for that is a little heavy, so instead removing
it now in favor of not generating the 'count' expression.

Addresses http://llvm.org/PR36263 .

Reviewers: aprantl, dblaikie, probinson

Reviewed By: aprantl

Subscribers: JDevlieghere, llvm-commits, dstenb

Differential Revision: https://reviews.llvm.org/D43387

llvm-svn: 325427
2018-02-17 11:06:53 +00:00