Commit Graph

3135 Commits

Author SHA1 Message Date
Djordje Todorovic 5aa5c943f7 Reland "[DebugInfo] Enable the debug entry values feature by default"
Differential Revision: https://reviews.llvm.org/D73534
2020-03-10 09:15:06 +01:00
Djordje Todorovic c15c68abdc [CallSiteInfo] Enable the call site info only for -g + optimizations
Emit call site info only in the case of '-g' + 'O>0' level.

Differential Revision: https://reviews.llvm.org/D75175
2020-03-09 12:12:44 +01:00
Igor Kudrin 3a1bc41a89 [DebugInfo] Print the actual value of an unknown section identifier.
This is a follow-up for D75609. As @dblaikie suggested, it prints
the actual number for an unknown section identifier when dumping
unit index sections.

Differential Revision: https://reviews.llvm.org/D75668
2020-03-06 21:46:04 +07:00
Fangrui Song 71e2ca6e32 [llvm-objdump] -d: print `00000000 <foo>:` instead of `00000000 foo:`
The new behavior matches GNU objdump. A pair of angle brackets makes tests slightly easier.

`.foo:` is not unique and thus cannot be used in a `CHECK-LABEL:` directive.
Without `-LABEL`, the CHECK line can match the `Disassembly of section`
line and causes the next `CHECK-NEXT:` to fail.

```
Disassembly of section .foo:

0000000000001634 .foo:
```

Bdragon: <> has metalinguistic connotation. it just "feels right"

Reviewed By: rupprecht

Differential Revision: https://reviews.llvm.org/D75713
2020-03-05 18:05:28 -08:00
Igor Kudrin 6e9c10f694 Fix typos in comment marks. 2020-03-05 20:01:45 +07:00
Igor Kudrin 1a837569db [DebugInfo] Refine the condition to detect CIEs.
The condition was not accurate enough and could interpret some FDEs in
.eh_frame or 64-bit DWARF .debug_frame sections as CIEs. Even though
such FDEs are unlikely in a normal situation, the wrong interpretation
could hide an issue in a buggy generator.

Differential Revision: https://reviews.llvm.org/D73886
2020-03-05 17:37:09 +07:00
Igor Kudrin cc61283bf6 [DebugInfo] Avoid crashing on an invalid section identifier.
A DWARFSectionKind is read from input. It is not validated on parsing,
so an unexpected value may result in reaching llvm_unreachable() in
DWARFUnitIndex::getColumnHeader() when dumping the index section.

Differential Revision: https://reviews.llvm.org/D75609
2020-03-05 10:54:43 +07:00
Amy Huang 5b3b21f025 [DebugInfo] Fix for adding "returns cxx udt" option to functions in CodeView.
Summary:
This change checks for the return type in the frontend and adds a flag
to the DISubroutineType to indicate that the option should be added in
CodeViewDebug.

Previously function types sometimes appeared twice in the PDB: once with
"returns cxx udt" and once without.
See https://bugs.llvm.org/show_bug.cgi?id=44785.

Reviewers: rnk, asmith

Subscribers: hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D75215
2020-03-03 14:00:08 -08:00
Vedant Kumar b5b21812dc test: Adjust no-dbg-value-after-terminator.mir to use `not --crash` 2020-03-03 13:30:31 -08:00
Vedant Kumar f002ee55c7 [MachineVerifier] Remove placement rule exception for debug entry values
There should not be an exception allowing debug entry values to be
placed after a terminator.

Differential Revision: https://reviews.llvm.org/D75559
2020-03-03 13:02:18 -08:00
Vedant Kumar 2bf496620c [LiveDebugValues] Do not insert DBG_VALUEs after a MBB terminator
This fixes a miscompile that happened because a DBG_VALUE interfered
with the MachineOutliner's liveness analysis.

Inserting a DBG_VALUE after a terminator breaks predicates on MBB such
as isReturnBlock(). And the resulting DBG_VALUE cannot be "live".

I plan to introduce a MachineVerifier check for this situation in a
follow up.

rdar://59859175

Testing: check-llvm, LNT build with a stage2 compiler & entry values
enabled

Differential Revision: https://reviews.llvm.org/D75548
2020-03-03 13:00:52 -08:00
Justin Bogner 831fe8dc4c Restore `REQUIRES: default_triple` to a test
This was accidentally removed as part of 7683a084de "Remove lit
feature object-emission"

7683a084de Remove lit feature object-emission
2020-03-03 09:43:36 -08:00
Alok Kumar Sharma 6f029dadf6 [DebugInfo] Avoid generating duplicate llvm.dbg.value
Summary:
This is to avoid generating duplicate llvm.dbg.value instrinsic if it already exists after the Instruction.

Before inserting llvm.dbg.value instruction, LLVM checks if the same instruction is already present before the instruction to avoid duplicates.
Currently it misses to check if it already exists after the instruction.
flang generates IR like this.

%4 = load i32, i32* %i1_311, align 4, !dbg !42
call void @llvm.dbg.value(metadata i32 %4, metadata !35, metadata !DIExpression()), !dbg !33
When this IR is processed in llvm, it ends up inserting duplicates.
%4 = load i32, i32* %i1_311, align 4, !dbg !42
call void @llvm.dbg.value(metadata i32 %4, metadata !35, metadata !DIExpression()), !dbg !33
call void @llvm.dbg.value(metadata i32 %4, metadata !35, metadata !DIExpression()), !dbg !33
We have now updated LdStHasDebugValue to include the cases when instruction is already
followed by same dbg.value instruction we intend to insert.

Now,

Definition and usage of function LdStHasDebugValue are deleted.
RemoveRedundantDbgInstrs is called for the cleanup of duplicate dbg.value's

Testing:
Added unit test for validation
check-llvm
check-debuginfo (the debug info integration tests)

Reviewers: aprantl, probinson, dblaikie, jmorse, jini.susan.george
SouraVX, awpandey, dstenb, vsk

Reviewed By: aprantl, jmorse, dstenb, vsk

Differential Revision: https://reviews.llvm.org/D74030
2020-03-03 09:56:45 +05:30
David Blaikie 4ce3e5074b DebugInfo: Separate different debug_macinfo contributions & print the offset of a contribution 2020-03-02 19:30:30 -08:00
Vedant Kumar 0368b42295 [entry values] ARM: Add a describeLoadedValue override (PR45025)
As a narrow stopgap for the assertion failure described in PR45025, add
a describeLoadedValue override to ARMBaseInstrInfo and use it to detect
copies in which the forwarding reg is a super/sub reg of the copy
destination. For the moment this is unsupported.

Several follow ups are possible:

1) Handle VORRq. At the moment, we do not, because isCopyInstrImpl
   returns early when !MI.isMoveReg().

2) In the case where forwarding reg is a super-reg of the copy
   destination, we should be able to describe the forwarding reg as a
   subreg within the copy destination. I'm not 100% sure about this, but
   it looks like that's what's done in AArch64InstrInfo.

3) In the case where the forwarding reg is a sub-reg of the copy
   destination, maybe we could describe the forwarding reg using the
   copy destinaion and a DW_OP_LLVM_fragment (I guess this should be
   possible after D75036).

https://bugs.llvm.org/show_bug.cgi?id=45025
rdar://59772698

Differential Revision: https://reviews.llvm.org/D75273
2020-02-28 14:30:40 -08:00
Djordje Todorovic 43704459b1 [NFC] [Test commit] Testing commit access with new email 2020-02-28 12:01:52 +01:00
Igor Kudrin 7a9d00f261 [DebugInfo] Fix parsing DWARF64 units in DWP.
The integrity check code allowed only DWARF32 units.

Differential Revision: https://reviews.llvm.org/D75178
2020-02-28 15:35:51 +07:00
Igor Kudrin 044308e9ed [DebugInfo] Avoid crashing when parsing an invalid unit header in DWP.
The integrity checks for index entries in DWARFUnitHeader::extract()
might cause the function to return before checking the state of an
Error object, which leads to a crash in runtime. The patch fixes the
issue by moving the checks in a safe place.

Differential Revision: https://reviews.llvm.org/D75177
2020-02-28 15:35:51 +07:00
Pavel Labath 5754a61e57 [DataExtractor] Improve error message when we run off the end of the buffer
Summary: Include the offset at which this happened.

Reviewers: dblaikie, jhenderson

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D75265
2020-02-28 09:02:33 +01:00
Vedant Kumar a993720397 [LiveDebugValues] Encode register location within VarLoc IDs [3/3]
This is part 3 of a 3-part series to address a compile-time explosion
issue in LiveDebugValues.

---

Start encoding register locations within VarLoc IDs, and take advantage
of this encoding to speed up transferRegisterDef.

There is no fundamental algorithmic change: this patch simply swaps out
SparseBitVector in favor of CoalescingBitVector. That changes iteration
order (hence the test updates), but otherwise this patch is NFCI.

The only interesting change is in transferRegisterDef. Instead of doing:

```
KillSet = {}
for (ID : OpenRanges.getVarLocs())
  if (DeadRegs.count(ID))
    KillSet.add(ID)
```

We now do:

```
KillSet = {}
for (Reg : DeadRegs)
  for (ID : intervalsReservedForReg(Reg, OpenRanges.getVarLocs()))
    KillSet.add(ID)
```

By not visiting each open location every time we visit an instruction,
this eliminates some potentially quadratic behavior. The new
implementation basically does a constant amount of work per instruction
because the interval map lookups are very fast.

For a file in WebKit, this brings the time spent in LiveDebugValues down
from ~2.5 minutes to 4 seconds, reducing compile time spent in that pass
from 28% of the total to just over 1%.

Before:

```
2.49 min   27.8%	0 s	LiveDebugValues::process
2.41 min   27.0%	5.40 s	LiveDebugValues::transferRegisterDef
1.51 min   16.9%	1.51 min LiveDebugValues::VarLoc::isDescribedByReg() const
32.73 s    6.1%		8.70 s	 llvm::SparseBitVector<128u>::SparseBitVectorIterator::operator++()
```

After:

```
4.53 s	1.1%	0 s	LiveDebugValues::process
3.00 s	0.7%	107.00 ms		LiveDebugValues::transferRegisterCopy
892.00 ms	0.2%	406.00 ms	LiveDebugValues::transferSpillOrRestoreInst
404.00 ms	0.1%	32.00 ms	LiveDebugValues::transferRegisterDef
110.00 ms	0.0%	2.00 ms		  LiveDebugValues::getUsedRegs
57.00 ms	0.0%	1.00 ms		  std::__1::vector<>::push_back
40.00 ms	0.0%	1.00 ms		  llvm::CoalescingBitVector<>::find(unsigned long long)
```

FWIW, I tried the same approach using SparseBitVector, but got bad
results. To do that, I had to extend SparseBitVector to support 64-bit
indices and expose its lower bound operation. The problem with this is
that the performance is very hard to predict: SparseBitVector's lower
bound operation falls back to O(n) linear scans in a std::list if you're
not /very/ careful about managing iteration order. When I profiled this
the performance looked worse than the baseline.

You can see the full CoalescingBitVector-based implementation here:

  https://github.com/vedantk/llvm-project/commits/try-coalescing

You can see the full SparseBitVector-based implementation here:

  https://github.com/vedantk/llvm-project/commits/try-sparsebitvec-find

Depends on D74984 and D74985.

Differential Revision: https://reviews.llvm.org/D74986
2020-02-27 12:39:47 -08:00
Pierre-vh f64e457cb7 [Transforms][Debugify] Ignore PHI nodes when checking for DebugLocs
Fix for: https://bugs.llvm.org/show_bug.cgi?id=37964

Differential Revision: https://reviews.llvm.org/D75242
2020-02-27 16:14:11 +00:00
Djordje Todorovic 58d9e8194e [DebugInfo][ARM] Fix noreg case when checkig if it is an addImm
This fixes a build failure with an ARM buildbot.

Differential Revision: https://reviews.llvm.org/D75231
2020-02-27 11:39:19 +01:00
David Stenberg 6d857166d2 [DebugInfo] Describe call site values for chains of expression producing instrs
Summary:
If the describeLoadedValue() hook produced a DIExpression when
describing a instruction, and it was not possible to emit a call site
entry directly (the value operand was not an immediate nor a preserved
register), then that described value could not be inserted into the
worklist, and would instead be dropped, meaning that the parameter's
call site value couldn't be described.

This patch extends the worklist so that each entry has an DIExpression
that is built up when iterating through the instructions.

This allows us to describe instruction chains like this:

  $reg0 = mv $fp
  $reg0 = add $reg0, offset
  call @call_with_offseted_fp

Since DW_OP_LLVM_entry_value operations can't be combined with any other
expression, such call site entries will not be emitted. I have added a
test, dbgcall-site-expr-entry-value.mir, which verifies that we don't
assert or emit broken DWARF in such cases.

Reviewers: djtodoro, aprantl, vsk

Reviewed By: djtodoro, vsk

Subscribers: hiraditya, llvm-commits

Tags: #debug-info, #llvm

Differential Revision: https://reviews.llvm.org/D75036
2020-02-27 11:18:51 +01:00
Scott Linder 481b1c8380 [AMDGPU] Implement wave64 DWARF register mapping
Summary:
Implement the DWARF register mapping described in
llvm/docs/AMDGPUUsage.rst

This is currently limited to wave64 VGPRs/AGPRs.

This also includes some minor changes in AMDGPUInstPrinter,
AMDGPUMCTargetDesc, and AMDGPUAsmParser to make generating CFI assembly
text and ELF sections possible to ease testing, although complete CFI
support is not yet implemented.

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D74915
2020-02-25 14:00:01 -05:00
Igor Kudrin bd2df13ee0 [DebugInfo] Fix printing CIE offsets in EH FDEs.
While the value of the CIE pointer field in a DWARF FDE record is
an offset to the corresponding CIE record from the beginning of
the section, for EH FDE records it is relative to the current offset.
Previously, we did not make that distinction when dumped both kinds
of FDE records and just printed the same value for the CIE pointer
field and the CIE offset; that was acceptable for DWARF FDEs but was
wrong for EH FDEs.

This patch fixes the issue by explicitly printing the offset of the
linked CIE object.

Differential Revision: https://reviews.llvm.org/D74613
2020-02-25 17:10:29 +07:00
Sjoerd Meijer 7efabe5c7d [MIR][ARM] MachineOperand comments
This adds infrastructure to print and parse MIR MachineOperand comments.
The motivation for the ARM backend is to print condition code names instead of
magic constants that are difficult to read (for human beings). For example,
instead of this:

  dead renamable $r2, $cpsr = tEOR killed renamable $r2, renamable $r1, 14, $noreg
  t2Bcc %bb.4, 0, killed $cpsr

we now print this:

  dead renamable $r2, $cpsr = tEOR killed renamable $r2, renamable $r1, 14 /* CC::always */, $noreg
  t2Bcc %bb.4, 0 /* CC:eq */, killed $cpsr

This shows that MachineOperand comments are enclosed between /* and */. In this
example, the EOR instruction is not conditionally executed (i.e. it is "always
executed"), which is encoded by the 14 immediate machine operand. Thus, now
this machine operand has /* CC::always */ as a comment. The 0 on the next
conditional branch instruction represents the equal condition code, thus now
this operand has /* CC:eq */ as a comment.

As it is a comment, the MI lexer/parser completely ignores it. The benefit is
that this keeps the change in the lexer extremely minimal and no target
specific parsing needs to be done. The changes on the MIPrinter side are also
minimal, as there is only one target hooks that is used to create the machine
operand comments.

Differential Revision: https://reviews.llvm.org/D74306
2020-02-24 14:19:21 +00:00
Djordje Todorovic 2f215cf36a Revert "Reland "[DebugInfo] Enable the debug entry values feature by default""
This reverts commit rGfaff707db82d.
A failure found on an ARM 2-stage buildbot.
The investigation is needed.
2020-02-20 14:41:39 +01:00
Igor Kudrin be66cf221b [DebugInfo] Read CIE pointer as a relocatable value.
The CIE pointer field of an FDE record contains an offset to
a corresponding CIE record. In object files, this value comes with
relocation because the value has to be fixed when a linker combines
the final section from multiple sources. In most object files there is
only one CIE record at offset 0 of the .debug_frame section, so reading
a relocated or a raw value makes no difference. However, in partially
linked object files there are multiple CIE records and the relocations
should be applied to recover the right offset value.

Differential Revision: https://reviews.llvm.org/D74612
2020-02-20 09:12:05 +07:00
Djordje Todorovic faff707db8 Reland "[DebugInfo] Enable the debug entry values feature by default"
Differential Revision: https://reviews.llvm.org/D73534
2020-02-19 11:12:26 +01:00
Fangrui Song d840e54523 [DebugInfo][test] Fix section flags/type to avoid warning/error in the future
A future MC change may add a warning/error when a .section directive
specifies incorrect sh_flags/sh_type. Fix the tests to use correct
sh_flags/sh_type.
2020-02-18 20:51:41 -08:00
Thomas Lively ca9ba76481 [WebAssembly] Replace all calls with generalized multivalue calls
Summary:
Extends the multivalue call infrastructure to tail calls, removes all
legacy calls specialized for particular result types, and removes the
CallIndirectFixup pass, since all indirect call arguments are now
fixed up directly in the post-insertion hook.

In order to keep supporting pretty-printed defs and uses in test
expectations, MCInstLower now inserts an immediate containing the
number of defs for each call and call_indirect. The InstPrinter is
updated to query this immediate if it is present and determine which
MCOperands are defs and uses accordingly.

Depends on D72902.

Reviewers: aheejin

Subscribers: dschuff, mgorny, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D74192
2020-02-18 15:55:20 -08:00
Djordje Todorovic 2bf44d11cb Revert "Reland "[DebugInfo] Enable the debug entry values feature by default""
This reverts commit rGa82d3e8a6e67.
2020-02-18 16:38:11 +01:00
Djordje Todorovic a82d3e8a6e Reland "[DebugInfo] Enable the debug entry values feature by default"
This patch enables the debug entry values feature.

  - Remove the (CC1) experimental -femit-debug-entry-values option
  - Enable it for x86, arm and aarch64 targets
  - Resolve the test failures
  - Leave the llc experimental option for targets that do not
    support the CallSiteInfo yet

Differential Revision: https://reviews.llvm.org/D73534
2020-02-18 14:41:08 +01:00
Fangrui Song 895cad1a13 [AsmPrinter][XRay] Omit unique ID for xray_instr_map and xray_fn_idx
Follow-up for D74006.
2020-02-14 21:10:46 -08:00
Ted Woodward efef165f82 Clean up hexagon builder after object-emission removal
Original commit:
https://reviews.llvm.org/rG7683a084de6bd2637f2351f53389df8b610566cf
2020-02-13 13:17:42 -06:00
Yuanfang Chen 4ad7685258 Revert "Revert "Reland "[Support] make report_fatal_error `abort` instead of `exit`"""
This reverts commit 80a34ae311 with fixes.

Previously, since bots turning on EXPENSIVE_CHECKS are essentially turning on
MachineVerifierPass by default on X86 and the fact that
inline-asm-avx-v-constraint-32bit.ll and inline-asm-avx512vl-v-constraint-32bit.ll
are not expected to generate functioning machine code, this would go
down to `report_fatal_error` in MachineVerifierPass. Here passing
`-verify-machineinstrs=0` to make the intent explicit.
2020-02-13 10:16:06 -08:00
Yuanfang Chen 17122ec10a Revert "Revert "Revert "Reland "[Support] make report_fatal_error `abort` instead of `exit`""""
This reverts commit bb51d24330.
2020-02-13 10:08:05 -08:00
Yuanfang Chen bb51d24330 Revert "Revert "Reland "[Support] make report_fatal_error `abort` instead of `exit`"""
This reverts commit 80a34ae311 with fixes.

On bots llvm-clang-x86_64-expensive-checks-ubuntu and
llvm-clang-x86_64-expensive-checks-debian only,
llc returns 0 for these two tests unexpectedly. I tweaked the RUN line a little
bit in the hope that LIT is the culprit since this change is not in the
codepath these tests are testing.
llvm\test\CodeGen\X86\inline-asm-avx-v-constraint-32bit.ll
llvm\test\CodeGen\X86\inline-asm-avx512vl-v-constraint-32bit.ll
2020-02-13 10:02:53 -08:00
Igor Kudrin 2ba4df6c11 [DebugInfo] Fix dumping CIE ID in .eh_frame sections.
We do not keep the actual value of the CIE ID field, because it is
predefined, and use a constant when dumping a CIE record. The issue
was that the predefined value is different for .debug_frame and
.eh_frame sections, but we always printed the one which corresponds
to .debug_frame. The patch fixes that by choosing an appropriate
constant to print.

See the following for more information about .eh_frame sections:
https://refspecs.linuxfoundation.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/ehframechpt.html

Differential Revision: https://reviews.llvm.org/D73627
2020-02-13 15:42:14 +07:00
Vedant Kumar 34d9f93977 [AddressSanitizer] Ensure only AllocaInst is passed to dbg.declare
Various parts of the LLVM code generator assume that the address
argument of a dbg.declare is not a `ptrtoint`-of-alloca. ASan breaks
this assumption, and this results in local variables sometimes being
unavailable at -O0.

GlobalISel, SelectionDAG, and FastISel all do not appear to expect
dbg.declares to have a `ptrtoint` as an operand. This means that they do
not place entry block allocas in the usual side table reserved for local
variables available in the whole function scope. This isn't always a
problem, as LLVM can try to lower the dbg.declare to a DBG_VALUE, but
those DBG_VALUEs can get dropped for all the usual reasons DBG_VALUEs
get dropped. In the ObjC test case I'm looking at, the cause happens to
be that `replaceDbgDeclare` has hoisted dbg.declares into the entry
block, causing LiveDebugValues to "kill" the DBG_VALUEs because the
lexical dominance check fails.

To address this, I propose:

1) Have ASan (always) pass an alloca to dbg.declares (this patch). This
   is a narrow bugfix for -O0 debugging.

2) Make replaceDbgDeclare not move dbg.declares around. This should be a
   generic improvement for optimized debug info, as it would prevent the
   lexical dominance check in LiveDebugValues from killing as many
   variables.

   This means reverting llvm/r227544, which fixed an assertion failure
   (llvm.org/PR22386) but no longer seems to be necessary. I was able to
   complete a stage2 build with the revert in place.

rdar://54688991

Differential Revision: https://reviews.llvm.org/D74369
2020-02-12 11:24:02 -08:00
Djordje Todorovic 97ed706a96 Revert "[DebugInfo] Enable the debug entry values feature by default"
This reverts commit rG9f6ff07f8a39.

Found a test failure on clang-with-thin-lto-ubuntu buildbot.
2020-02-12 11:59:04 +01:00
Djordje Todorovic 9f6ff07f8a [DebugInfo] Enable the debug entry values feature by default
This patch enables the debug entry values feature.

  - Remove the (CC1) experimental -femit-debug-entry-values option
  - Enable it for x86, arm and aarch64 targets
  - Resolve the test failures
  - Leave the llc experimental option for targets that do not
    support the CallSiteInfo yet

Differential Revision: https://reviews.llvm.org/D73534
2020-02-12 10:25:14 +01:00
Igor Kudrin 675c4bebaf [DebugInfo] Do not dump header field for pre-DWARFv5 address tables.
As there is no header in pre-DWARFv5 address tables, and we fill
the class data members with some artificial values, we should not
dump them as that might be misleading.

Differential Revision: https://reviews.llvm.org/D74195
2020-02-12 13:33:00 +07:00
Yuanfang Chen 80a34ae311 Revert "Reland "[Support] make report_fatal_error `abort` instead of `exit`""
This reverts commit rGcd5b308b828e, rGcd5b308b828e, rG8cedf0e2994c.

There are issues to be investigated for polly bots and bots turning on
EXPENSIVE_CHECKS.
2020-02-11 20:41:53 -08:00
Yuanfang Chen 8cedf0e299 Reland "[Support] make report_fatal_error `abort` instead of `exit`"
Summary:
Reland D67847 after D73742 is committed. Replace `sys::Process::Exit(1)`
with `abort` in `report_fatal_error`.

After this patch, for tools turning on `CrashRecoveryContext`,
crash handler installed by `CrashRecoveryContext` is called unless
they installed a non-returning handler using `llvm::install_fatal_error_handler`
like `cc1_main` currently does.

Reviewers: rnk, MaskRay, aganea, hans, espindola, jhenderson

Subscribers: jholewinski, qcolombet, dschuff, jyknight, emaste, sdardis, nemanjai, jvesely, nhaehnle, sbc100, jgravelle-google, hiraditya, aheejin, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, sabuasal, niosHD, jrtc27, zzheng, edward-jones, atanasyan, steven_wu, rogfer01, MartinMosbeck, brucehoult, the_o, dexonsmith, PkmX, rupprecht, jocewei, jsji, Jim, dmgreen, lenary, s.egerton, pzheng, sameer.abuasal, apazos, luismarques, kerbowa, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D74456
2020-02-11 18:20:40 -08:00
lewis-revill a6bd1256ce [DebugInfo] Call site entries cannot be generated for FrameSetup calls
Instructions marked as FrameSetup do not cause requestLabelAfterInsn to
be called and so no such label is generated. Call instructions which
require call site entries to be generated require this label to be
present in order to calculate the return PC offset/address, but the
check for whether the call instruction is marked as FrameSetup was not
present.

Therefore in the case where a call instruction is marked as FrameSetup,
an assertion failure occurs if a call site entry is to be generated.
This is the case with RISC-V's implementation of save/restore via
library calls.

Differential Revision: https://reviews.llvm.org/D71593
2020-02-11 21:23:18 +00:00
OCHyams 1e40799324 [DebugInfo] Teach LDV how to handle identical variable fragments
LiveDebugVariables uses interval maps to explicitly represent DBG_VALUE
intervals. DBG_VALUEs are filtered into an interval map based on their {
Variable, DIExpression }. The interval map will coalesce adjacent entries that
use the same { Location }.  Under this model, DBG_VALUEs which refer to the same
bits of the same variable will be filtered into different interval maps if they
have different DIExpressions which means the original intervals will not be
properly preserved.

This patch fixes the problem by using { Variable, Fragment } to filter the
DBG_VALUEs into maps, and coalesces adjacent entries iff they have the same
{ Location, DIExpression } pair.

The solution is not perfect because we see the similar issues appear when
partially overlapping fragments are encountered, but is far simpler than a
complete solution (i.e. D70121).

Fixes: pr41992, pr43957
Reviewed By: aprantl
Differential Revision: https://reviews.llvm.org/D74053
2020-02-11 10:20:24 +00:00
Ted Woodward 7683a084de Remove lit feature object-emission
Summary: The lit feature object-emission was added because Hexagon did not support the integrated assembler, so some tests needed to be turned off with a Hexagon target. Hexagon now supports the integrated assembler, so this feature can be removed.

Reviewers: bcain, kparzysz, jverma, whitequark, JDevlieghere

Reviewed By: JDevlieghere

Subscribers: mehdi_amini, hiraditya, steven_wu, dexonsmith, arphaman, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73568
2020-02-10 15:57:56 -06:00
James Henderson 1dc62d0358 [DebugInfo][test] Replace pre-canned binary test
The DebugInfo/dwarfdump-invalid-line-table test used a pre-canned binary
generated by a fuzzer to demonstrate a bug fix. Unfortunately, the
binary is rigid and requires hand-editing if we change behaviour, such
as rejecting certain properties within it (as I plan on doing in another
change).

Rather than hand-edit the binary, I have replaced it with two tests. The
first tests the high-level code path from the debug line parser that
produces the same error as this test previously did, and the second is a
set of unit test cases that comprehensively cover the
FormValue::skipValue method, which in turn covers the area that the
original bug fix touched.

Reviewed by: MaskRay, dblaikie

Differential Revision: https://reviews.llvm.org/D74202
2020-02-10 13:54:40 +00:00
Sourabh Singh Tomar 84e5760a16 [DebugInfo]: Reorderd the emission of debug_str section.
Summary:
This patch reorders the emission of debug_str section, so that
string can come after macros.
This is necessary for macro forms like DW_MACRO_define_strp,
which emits macro as a string in debug_str section.
2020-02-07 11:15:55 +05:30
Jeremy Morse 6531a78ac4 Revert "[DebugInfo] Remove some users of DBG_VALUEs IsIndirect field"
This reverts commit ed29dbaafa.

I'm backing out D68945, which as the discussion for D73526 shows, doesn't
seem to handle the -O0 path through the codegen backend correctly. I'll
reland the patch when a fix is worked out, apologies for all the churn.
The two parent commits are part of this revert too.

Conflicts:
	llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
	llvm/test/DebugInfo/X86/dbg-addr-dse.ll

SelectionDAGBuilder conflict is due to a nearby change in e39e2b4a79
that's technically unrelated. dbg-addr-dse.ll conflicted because
41206b61e3 (legitimately) changes the order of two lines.

There are further modifications to dbg-value-func-arg.ll: it landed after
the patch being reverted, and I've converted indirection to be represented
by the isIndirect field rather than DW_OP_deref.
2020-02-06 14:41:40 +00:00
Jeremy Morse ece761427f Revert "[DebugInfo][DAG] Distinguish different kinds of location indirection"
This reverts commit 3137fe4d23.

I'm backing out D68945, which this patch is a follow up for. It'll be
re-landed when D68945 is fixed.

The changes to dbg-value-func-arg.ll occur because our handling of certain
kinds of location now mixes up indirection that happens at different points
in a DIExpression. While this is a regression, it's a return to the prior
behaviour while a better patch is sought.
2020-02-06 14:41:40 +00:00
Jeremy Morse ed5998d21e Revert "[SafeStack][DebugInfo] Insert DW_OP_deref in correct location"
This reverts commit 2d3174c4df.

The overall solution for this problem is reverting D68945, which wasn't
handling the -O0 path through the codegen backend correctly. See:
discussion in D73526.
2020-02-06 14:41:39 +00:00
David Blaikie a4b590dd39 DebugInfo: Stabilize DW_OP_convert tests so they don't depend on register allocation, etc 2020-02-05 14:28:03 -08:00
Djordje Todorovic de90d73e03 [DebugInfo] Avoid the call site param for mem instrs with multiple defs
We currently only handle mem instructions with a single define.
Avoid the call site parameter debug info when we find the case with
multiple defs, rather than throwing an assert.

Differential Revision: https://reviews.llvm.org/D73954
2020-02-05 10:03:14 +01:00
David Blaikie ec50e10db4 DebugInfo: Hash DW_OP_convert in loclists when using Split DWARF
Originally committed in: 1ced28cbe7
            Reverted in: f75301d16d

(reverted due to tests failing on non-linux/x86 targets, tests have since been
generalized and specialized... since Split DWARF isn't supported on non-elf
targets anyway and we have no way to run on "whatever elf target is available"
so they fail on MacOS without an explicit target triple)

This code was incorrectly emitting extra bytes into arbitrary parts of
the object file when it was meant to be hashing them to compute the DWO
ID.

Follow-up patch(es) will refactor this API somewhat to make such bugs
harder to introduce, hopefully.
2020-02-04 19:25:47 -08:00
David Blaikie 9329cfca84 DebugInfo: convert-debugloc.ll generalize to run on ppc64le
This target produces a location list for the location, so split the
match between lines to allow for a location list match.
2020-02-04 19:14:22 -08:00
David Blaikie a1c338d70b DebugInfo: Fix convert-loclist.ll Split DWARF variant to use a hardcoded triple
Since we don't support Split DWARF emission on non-ELF formats, hardcode
an elfine triple (we don't have a way to ask for "any ELF triple" it
seems, so hardcoded will have to do)
2020-02-04 19:02:11 -08:00
David Blaikie 57c54ddd7f Recommit: DebugInfo: Check DW_OP_convert in loclists with Split DWARF
Originally committed in: 552a8fe12b
            Reverted in: f75301d16d

Reverted because it was running llc directly (rather than %llc_dwarf)
which uses COFF files on Windows which LLVM doesn't support all DWARF
features in.

This functionality isn't fully working, but sets up the testing for a
follow-on patch that demonstrates and fixes the brokenness related to
DWO ID hashing this construct.
2020-02-04 18:37:06 -08:00
David Blaikie 7f57f13cd6 DebugInfo: use a symbolic DIE reference in convert-loclist.ll 2020-02-04 18:23:22 -08:00
David Blaikie b0cd0b7c90 Reapply: DebugInfo: Add missing test coverage for DW_OP_convert in loclists
Originally committed in: 5327b917e3
      and follow on fix: 4f281f0474

            Reverted in: 191a9a78b3
	            and: f75301d16d

Reverted because it wasn't portable between the targets it was running
on. Using %llc_dwarf ensures the target triple is always elfine and thus
DWARF compatible.
2020-02-04 18:18:45 -08:00
David Blaikie cd9142ed8a DebugInfo: Generalize test/DebugInfo/X86/convert-linked.ll to run with different architectures 2020-02-04 18:02:03 -08:00
David Blaikie 1b787f53c6 DebugInfo: Generalize test/DebugInfo/X86/convert-inlined.ll
This test was hardcoded to only run on x86-64-linux-gnu and was overly
constrained by CHECK-NEXTing every line for an exact match.
2020-02-04 17:51:35 -08:00
David Blaikie 6f738f62ab DebugInfo: convert-debugloc.ll remove erroneous CHECK 2020-02-04 17:39:38 -08:00
David Blaikie efcd3967a6 DebugInfo: Generalize convert-debugloc.ll to run for multiple target architectures
This test was overly constrained & hardcoded only to x86-linux-gnu -
generalize the test & remove the hardcoded target triple.
2020-02-04 17:34:13 -08:00
Nico Weber 191a9a78b3 Revert "DebugInfo: Add missing test coverage for DW_OP_convert in loclists"
This reverts commit 5327b917e3.
Already fails on non-Linux at this commit.
2020-02-04 10:10:04 -05:00
Nico Weber f75301d16d Revert "DebugInfo: Check DW_OP_convert in loclists with Split DWARF"
and follow-ups.

This reverts commit 1ced28cbe7.
This reverts commit 4f281f0474.
This reverts commit 552a8fe12b.

The test fails on non-Linux.
2020-02-04 10:06:46 -05:00
Jeremy Morse 41206b61e3 [DebugInfo] Re-instate LiveDebugVariables scope trimming
This patch reverts part of r362750 / D62650, which stopped
LiveDebugVariables from trimming leading variable location ranges down
to only covering those instructions that are in scope. I've observed some
circumstances where the number of DBG_VALUEs in a function can be
amplified in an un-necessary way, to cover more instructions that are
out of scope, leading to very slow compile times. Trimming the range
of instructions that the variables cover solves the slow compile times.

The specific problem that r362750 tries to fix is addressed by the
assignment to RStart that I've added. Any variable location that begins
at the first instruction of a block will now be considered to begin at the
start of the block. While these sound the same, the have different
SlotIndexes, and the register allocator may shoehorn additional
instructions in between the two. The test added in the past
(wrong_debug_loc_after_regalloc.ll) still works with this modification.

live-debug-variables.ll has a range trimmed to not cover the prologue of
the function, while dbg-addr-dse.ll has a DBG_VALUE sink past one
instruction with no DebugLoc, which is expected behaviour.

Differential Revision: https://reviews.llvm.org/D73691
2020-02-04 14:51:06 +00:00
David Blaikie 1ced28cbe7 DebugInfo: Hash DW_OP_convert in loclists when using Split DWARF
This code was incorrectly emitting extra bytes into arbitrary parts of
the object file when it was meant to be hashing them to compute the DWO
ID.

Follow-up patch(es) will refactor this API somewhat to make such bugs
harder to introduce, hopefully.
2020-02-03 19:16:42 -08:00
David Blaikie 4f281f0474 DebugInfo: Fix convert-loclist.ll to handle different target instruction lengths 2020-02-03 18:44:18 -08:00
David Blaikie 552a8fe12b DebugInfo: Check DW_OP_convert in loclists with Split DWARF 2020-02-03 18:40:11 -08:00
David Blaikie 5327b917e3 DebugInfo: Add missing test coverage for DW_OP_convert in loclists 2020-02-03 18:21:27 -08:00
Fangrui Song 5a56a25b0b [CodeGenPrepare] Make TargetPassConfig required
The code paths in the absence of TargetMachine, TargetLowering or
TargetRegisterInfo are poorly tested. As rL285987 said, requiring
TargetPassConfig allows us to delete many (untested) checks littered
everywhere.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D73754
2020-02-02 09:28:45 -08:00
David Blaikie b33e5f3c3e DebugInfo: Split DWARF: Hash non-member function child DIEs
Significant missing hashing - as per the comment this was only meant to
skip member functions (unspecified, but I think it's legible as member
function declarations, not definitions) but was skipping all named
subprograms (so only hashed child DIEs for member function definitions -
because they didn't have a direct name, but only a name given indirectly
in the DW_AT_specification-referenced DIE)
2020-01-31 15:32:03 -08:00
David Blaikie dce2193358 DebugInfo: Simplify debug-macinfo-split-dwarf.ll
This test didn't need any local variables or parameters, and didn't need
to be checking the DWO ID or more detailed forms.

It was using -v to print the macro sections, but now that macro sections
are emitted when requested (-debug-macro) that's not needed either.
2020-01-31 13:09:58 -08:00
Igor Kudrin 16a0313ee3 [DWARF] Add support for 64-bit DWARF in .debug_names.
Differential Revision: https://reviews.llvm.org/D72900
2020-01-31 16:12:35 +07:00
Leonard Chan 2d3174c4df [SafeStack][DebugInfo] Insert DW_OP_deref in correct location
This patch addresses the issue found in https://bugs.llvm.org/show_bug.cgi?id=44585
where a DW_OP_deref was placed at the end of a dwarf expression, resulting in corrupt
symbols when debugging.

This is an attempt to reland with a few fixes for buildbot since I
haven't merged from master in a bit.

Differential Revision: https://reviews.llvm.org/D73526
2020-01-30 17:09:42 -08:00
Leonard Chan 3b23453b6c Revert "[SafeStack][DebugInfo] Insert DW_OP_deref in correct location"
This reverts commit fff6a1b0f1.

This was breaking a bunch of buildbots.
2020-01-30 16:18:41 -08:00
Leonard Chan fff6a1b0f1 [SafeStack][DebugInfo] Insert DW_OP_deref in correct location
This patch addresses the issue found in https://bugs.llvm.org/show_bug.cgi?id=44585
where a DW_OP_deref was placed at the end of a dwarf expression, resulting in
corrupt symbols when debugging.

Differential Revision: https://reviews.llvm.org/D73526
2020-01-30 15:58:37 -08:00
Nico Weber b998d481da attempt to fix symbolize-paths.s everywhere after cd68f4 2020-01-29 14:26:50 -05:00
Nico Weber cd68f4beaa attempt to fix symbolize-paths.s on windows 2020-01-29 14:23:00 -05:00
Sterling Augustine 0758ac4e0c Handle non-absolute include dirs properly for both dwarf4 and dwarf5.
Summary:
Add test case for the same. This test case will also serve as a
starting point for later symbolizer tests.

Reviewers: dblaikie, jdoerfert

Subscribers: hiraditya, llvm-commits, jhenderson

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73583
2020-01-29 10:51:51 -08:00
David Stenberg 6a2413c435 [ARM64] Debug info for structure argument missing DW_AT_location
Summary:
Prevent eliminating dbg_val due to COPY.

Fixes this
https://bugs.llvm.org/show_bug.cgi?id=40709

Patch by: Kamlesh Kumar (kamleshbhalui)

Reviewers: aprantl, dblaikie, vsk, dsanders

Reviewed By: dsanders

Subscribers: dstenb, kristof.beyls, hiraditya, llvm-commits

Tags: #debug-info, #llvm

Differential Revision: https://reviews.llvm.org/D73159
2020-01-29 10:56:23 +01:00
Jonathan Roelofs 7f93ff58e1 [llvm] Fix broken cases of 'CHECK[^:]*$' in tests 2020-01-28 09:52:59 -07:00
Adrian Prantl a095d149c2 Fix an assertion failure in DwarfExpression's subregister composition
This patch fixes an assertion failure in DwarfExpression that is
triggered when a complex fragment has exactly the size of a
subregister of the register the DBG_VALUE points to *and* there is no
DWARF encoding for the super-register.

I took the opportunity to replace/document some magic values with
static constructor functions to make this code less confusing to read.

rdar://problem/58489125

Differential Revision: https://reviews.llvm.org/D72938
2020-01-27 12:44:37 -08:00
Petr Hosek 369ea47b92 [Symbolize] Handle error after the notes loop
We always have to check the error, even if we're going to ignore it.
2020-01-27 11:00:27 -08:00
Vedant Kumar e08f205f5c Reland (again): [DWARF] Allow cross-CU references of subprogram definitions
This is a revert-of-revert (i.e. this reverts commit 802bec89, which
itself reverted fa4701e1 and 79daafc9) with a fix folded in. The problem
was that call site tags weren't emitted properly when LTO was enabled
along with split-dwarf. This required a minor fix. I've added a reduced
test case in test/DebugInfo/X86/fission-call-site.ll.

Original commit message:

This allows a call site tag in CU A to reference a callee DIE in CU B
without resorting to creating an incomplete duplicate DIE for the callee
inside of CU A.

We already allow cross-CU references of subprogram declarations, so it
doesn't seem like definitions ought to be special.

This improves entry value evaluation and tail call frame synthesis in
the LTO setting. During LTO, it's common for cross-module inlining to
produce a call in some CU A where the callee resides in a different CU,
and there is no declaration subprogram for the callee anywhere. In this
case llvm would (unnecessarily, I think) emit an empty DW_TAG_subprogram
in order to fill in the call site tag. That empty 'definition' defeats
entry value evaluation etc., because the debugger can't figure out what
it means.

As a follow-up, maybe we could add a DWARF verifier check that a
DW_TAG_subprogram at least has a DW_AT_name attribute.

Update #1:

Reland with a fix to create a declaration DIE when the declaration is
missing from the CU's retainedTypes list. The declaration is left out
of the retainedTypes list in two cases:

1) Re-compiling pre-r266445 bitcode (in which declarations weren't added
   to the retainedTypes list), and
2) Doing LTO function importing (which doesn't update the retainedTypes
   list).

It's possible to handle (1) and (2) by modifying the retainedTypes list
(in AutoUpgrade, or in the LTO importing logic resp.), but I don't see
an advantage to doing it this way, as it would cause more DWARF to be
emitted compared to creating the declaration DIEs lazily.

Update #2:

Fold in a fix for call site tag emission in the split-dwarf + LTO case.

Tested with a stage2 ThinLTO+RelWithDebInfo build of clang, and with a
ReleaseLTO-g build of the test suite.

rdar://46577651, rdar://57855316, rdar://57840415, rdar://58888440

Differential Revision: https://reviews.llvm.org/D70350
2020-01-27 10:52:34 -08:00
Igor Kudrin 8f3d47c54a [DWARF] Do not pass Version to DWARFExpression. NFCI.
The Version was used only to determine the size of an operand of
DW_OP_call_ref. The size was 4 for all versions apart from 2, but
the DW_OP_call_ref operation was introduced only in DWARF3. Thus,
the code may be simplified and using of Version may be eliminated.

Differential Revision: https://reviews.llvm.org/D73264
2020-01-27 19:08:46 +07:00
David Stenberg 13d4ef9ac0 Improvements to call site register worklist
Summary:
This fixes PR44118. For cases where we have a chain like this:

  R8 = R1 (entry value)
  R0 = R8
  call @foo R0

the code that emits call site entries using entry values would not
follow that chain, instead emitting a call site entry with R8 as
location rather than R0. Such a case was discovered when originally
adding dbgcall-site-orr-moves.mir. This patch fixes that issue. This is
done by changing the ForwardedRegWorklist set to a map in which the
worklist registers always map to the parameter registers that they
describe.

Another thing this patch fixes is that worklist registers now can
describe more than one parameter register at a time. Such a case
occurred in dbgcall-site-interpretation.mir, resulting in a call site
entry not being emitted for one of the parameters.

Reviewers: djtodoro, NikolaPrica, aprantl, vsk

Reviewed By: vsk

Subscribers: hiraditya, llvm-commits

Tags: #debug-info, #llvm

Differential Revision: https://reviews.llvm.org/D73168
2020-01-27 12:41:42 +01:00
Vedant Kumar 802bec8961 Revert "Reland: [DWARF] Allow cross-CU references of subprogram definitions"
... as well as:
Revert "[DWARF] Defer creating declaration DIEs until we prepare call site info"

This reverts commit fa4701e197.

This reverts commit 79daafc903.

There have been reports of this assert getting hit:

CalleeDIE && "Could not find DIE for call site entry origin
2020-01-24 18:07:54 -08:00
Tom Weaver f5147765ba [DebugInfo][LiveDebugValues] Teach Live Debug Values About Meta Instructions
Previously LiveDebugValues pass would consider meta instructions that 'fiddle' with liveness of registers as register definitions when transfering register defs. This would mean that, for example, a KILL instruction would cause LiveDebugValues to terminate the range of an earlier DBG_VALUE instruction resulting in the none propogation of said DBG_VALUE instructions into later blocks.

This patch adds the check and a helpful comment, fixes a test that previously tested for the broken behaviour by coincidence and adds a test specifically for this.

reviewers: vsk, dstenb, djtodoro

Differential Revision: https://reviews.llvm.org/D73210
2020-01-24 16:29:05 +00:00
Djordje Todorovic 035c106f37 [DWARF][test] Test all the call-site realted attrs
Adding the test for the call site encoding in DWARF5 vs GNU extensions.
Some of the attributes were not covered by any test.

Differential Revision: https://reviews.llvm.org/D73266
2020-01-24 10:53:52 +01:00
Igor Kudrin 8306f55bfa [DWARF] Eliminate the DWARFDebugNames::Header::Padding field.
The padding field is reserved for DWARF and does not contain any useful
information. No need to read, store and report it.

Differential Revision: https://reviews.llvm.org/D73042
2020-01-23 15:11:58 +07:00
Igor Kudrin 5a9ef6c15f [DWARF] Support 64-bit DWARF in .debug_pubnames and similar tables.
Differential Revision: https://reviews.llvm.org/D73103
2020-01-23 14:51:00 +07:00
Igor Kudrin 6332990721 [DWARF] Support DWARF64 in DWARFDebugArangeSet.
This allows parsing Address Range Tables in the 64-bit DWARF format.

Differential Revision: https://reviews.llvm.org/D71876
2020-01-23 12:41:05 +07:00
Igor Kudrin dcff3961c2 [DWARF] Return Error from DWARFDebugArangeSet::extract().
This helps to detect and report parsing errors better.
The patch follows the ideas of LLDB's patches D59370 and D59381.

It adds tests for valid and some invalid cases. More checks and
tests to come. Note that the patch fixes validation of the Length
field because the value does not include the field itself.

The existing users are updated to show the error messages.

Differential Revision: https://reviews.llvm.org/D71875
2020-01-23 12:41:05 +07:00
Igor Kudrin 5e017c12d2 [DWARF] Allow empty address range tables.
Empty address range tables are allowed by the DWARF standard;
Moreover, generating them is recommended as a best practice, see
http://wiki.dwarfstd.org/index.php?title=Best_Practices#Generating_.debug_aranges_data

Differential Revision: https://reviews.llvm.org/D71931
2020-01-23 12:41:04 +07:00
Fangrui Song 55c81d4282 [test] Use yaml2obj -o %t instead of > %t
To improve consistency and avoid unneeded shell feature (output
redirection).

While here, make other changes to improve consistency

--docnum 1 => --docnum=1
-docnum=x => --docnum=x
2020-01-21 17:20:18 -08:00
Awanish Pandey 84c4c87e04 Recommit "[DWARF5][DebugInfo]: Added support for DebugInfo generation for auto return type for C++ member functions."
Summary:
This was reverted in 328e0f3dca due to
chromium bot failure. This revision addresses that case.

Original commit message:
Summary:
    This patch will provide support for auto return type for the C++ member
    functions. Before this return type of the member function is deduced and
    stored in the DIE.
    This patch includes llvm side implementation of this feature.

    Patch by: Awanish Pandey <Awanish.Pandey@amd.com>

    Reviewers: dblaikie, aprantl, shafik, alok, SouraVX, jini.susan.george

    Reviewed by: dblaikie

    Differential Revision: https://reviews.llvm.org/D70524
2020-01-20 15:13:13 +05:30
Fangrui Song 26ba1f77b5 [DebugInfo][test] Change two MIR tests to use -start-before=livedebugvalues instead of -start-after=patchable-function
To break order dependency between livedebugvalues and patchable-function.
2020-01-19 00:09:46 -08:00
Adrian Prantl 7b30370e5b Move the sysroot attribute from DIModule to DICompileUnit
[this re-applies c0176916a4
 with the correct commit message and phabricator link]

This addresses point 1 of PR44213.
https://bugs.llvm.org/show_bug.cgi?id=44213

The DW_AT_LLVM_sysroot attribute is used for Clang module debug info,
to allow LLDB to import a Clang module from source. Currently it is
part of each DW_TAG_module, however, it is the same for all modules in
a compile unit. It is more efficient and less ambiguous to store it
once in the DW_TAG_compile_unit.

This should have no effect on DWARF consumers other than LLDB.

Differential Revision: https://reviews.llvm.org/D71732
2020-01-17 12:55:40 -08:00
Adrian Prantl c17aee67f1 Revert "Rename DW_AT_LLVM_isysroot to DW_AT_LLVM_sysroot"
This reverts commit 12e479475a.

I accidentally landed this patch with the wrong commit message ...
2020-01-17 12:52:36 -08:00
Adrian Prantl 12e479475a Rename DW_AT_LLVM_isysroot to DW_AT_LLVM_sysroot
This is a purely cosmetic change that is NFC in terms of the binary
output. I bugs me that I called the attribute DW_AT_LLVM_isysroot
since the "i" is an artifact of GCC command line option syntax
(-isysroot is in the category of -i options) and doesn't carry any
useful information otherwise.

This attribute only appears in Clang module debug info.

Differential Revision: https://reviews.llvm.org/D71722
2020-01-17 09:36:48 -08:00
Yuanfang Chen 6e24c6037f Revert "[Support] make report_fatal_error `abort` instead of `exit`"
This reverts commit 647c3f4e47.

Got bots failure from sanitizer-windows and maybe others.
2020-01-15 17:52:25 -08:00
Yuanfang Chen 647c3f4e47 [Support] make report_fatal_error `abort` instead of `exit`
Summary:
This patch could be treated as a rebase of D33960. It also fixes PR35547.
A fix for `llvm/test/Other/close-stderr.ll` is proposed in D68164. Seems
the consensus is that the test is passing by chance and I'm not
sure how important it is for us. So it is removed like in D33960 for now.
The rest of the test fixes are just adding `--crash` flag to `not` tool.

** The reason it fixes PR35547 is

`exit` does cleanup including calling class destructor whereas `abort`
does not do any cleanup. In multithreading environment such as ThinLTO or JIT,
threads may share states which mostly are ManagedStatic<>. If faulting thread
tearing down a class when another thread is using it, there are chances of
memory corruption. This is bad 1. It will stop error reporting like pretty
stack printer; 2. The memory corruption is distracting and nondeterministic in
terms of error message, and corruption type (depending one the timing, it
could be double free, heap free after use, etc.).

Reviewers: rnk, chandlerc, zturner, sepavloff, MaskRay, espindola

Reviewed By: rnk, MaskRay

Subscribers: wuzish, jholewinski, qcolombet, dschuff, jyknight, emaste, sdardis, nemanjai, jvesely, nhaehnle, sbc100, arichardson, jgravelle-google, aheejin, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, jsji, lenary, s.egerton, pzheng, cfe-commits, MaskRay, filcab, davide, MatzeB, mehdi_amini, hiraditya, steven_wu, dexonsmith, rupprecht, seiya, llvm-commits

Tags: #llvm, #clang

Differential Revision: https://reviews.llvm.org/D67847
2020-01-15 17:05:13 -08:00
Vedant Kumar f0120556c7 [DWARF] Emit DW_AT_call_return_pc as an address
This reverts D53469, which changed llvm's DWARF emission to emit
DW_AT_call_return_pc as a function-local offset. Such an encoding is not
compatible with post-link block re-ordering tools and isn't standards-
compliant.

In addition to reverting back to the original DW_AT_call_return_pc
encoding, teach lldb how to fix up DW_AT_call_return_pc when the address
comes from an object file pointed-to by a debug map. While doing this I
noticed that lldb's support for tail calls that cross a DSO/object file
boundary wasn't covered, so I added tests for that. This latter case
exercises the newly added return PC fixup.

The dsymutil changes in this patch were originally included in D49887:
the associated test should be sufficient to test DW_AT_call_return_pc
encoding purely on the llvm side.

Differential Revision: https://reviews.llvm.org/D72489
2020-01-15 13:02:23 -08:00
Tom Weaver e7b2d9f470 [DBG][LIVEDEBUGVALUES][NFC] Add Targeted LiveDebugValues Behaviour Tests.
Adds 22 distinct tests that exercise the live-debug-values passes
expected behaviour.

reviewers: aprantl, vsk

Differential revision: https://reviews.llvm.org/D72515
2020-01-14 15:51:11 +00:00
Tom Weaver b10f6b7112 Revert "[DBG][LIVEDEBUGVALUES][NFC] Add Targeted LiveDebugValues Behaviour Tests."
This reverts commit 35787e3a06.
2020-01-14 15:12:02 +00:00
Tom Weaver 35787e3a06 [DBG][LIVEDEBUGVALUES][NFC] Add Targeted LiveDebugValues Behaviour Tests.
Adds 22 distinct tests that exercise the live-debug-values passes
expected behaviour.

reviewers: aprantl, vsk

Differential revision: https://reviews.llvm.org/D72515
2020-01-14 14:43:30 +00:00
Amy Huang 328e0f3dca Revert "[DWARF5][DebugInfo]: Added support for DebugInfo generation for auto return type for C++ member functions."
This reverts commit c958639098, which
causes a crash. See https://reviews.llvm.org/D70524 for details.
2020-01-13 13:58:14 -08:00
Alex Richardson 894f742acb [MIPS][ELF] Use PC-relative relocations in .eh_frame when possible
When compiling position-independent executables, we now use
DW_EH_PE_pcrel | DW_EH_PE_sdata4. However, the MIPS ABI does not define a
64-bit PC-relative ELF relocation so we cannot use sdata8 for the large
code model case. When using the large code model, we fall back to the
previous behaviour of generating absolute relocations.

With this change clang-generated .o files can be linked by LLD without
having to pass -Wl,-z,notext (which creates text relocations).
This is simpler than the approach used by ld.bfd, which rewrites the
.eh_frame section to convert absolute relocations into relative references.

I saw in D13104 that apparently ld.bfd did not accept pc-relative relocations
for MIPS ouput at some point. However, I also checked that recent ld.bfd
can process the clang-generated .o files so this no longer seems true.

Reviewed By: atanasyan
Differential Revision: https://reviews.llvm.org/D72228
2020-01-13 14:14:03 +00:00
Awanish Pandey c958639098 [DWARF5][DebugInfo]: Added support for DebugInfo generation for auto return type for C++ member functions.
Summary:
This patch will provide support for auto return type for the C++ member
functions. Before this return type of the member function is deduced and
stored in the DIE.
This patch includes llvm side implementation of this feature.

Patch by: Awanish Pandey <Awanish.Pandey@amd.com>

Reviewers: dblaikie, aprantl, shafik, alok, SouraVX, jini.susan.george

Reviewed by: dblaikie

Differential Revision: https://reviews.llvm.org/D70524
2020-01-13 12:26:13 +05:30
Matt Arsenault f26ed6e47c llc: Change behavior of -mcpu with existing attribute
Don't overwrite existing target-cpu attributes.

I've often found the replacement behavior annoying, and this is
inconsistent with how the fast math command line flags interact with
the function attributes.

Does not yet change target-features, since I think that should behave
as a concatenation.
2020-01-07 10:10:25 -05:00
David Blaikie b350c666ab Revert "DebugInfo: Fix rangesBaseAddress DICompileUnit bitcode serialization/deserialization"
Seeing some curious CFI failures internally - which makes little sense
to me, as I don't think anyone is using this flag (even us,
internally)... so sounds like a bug in my code somewhere (possibly a
latent one that propagating this flag exposed, not sure). Reverting
while I investigate.

This reverts commit c51b45e32e.
2019-12-30 22:33:35 -08:00
David Blaikie c51b45e32e DebugInfo: Fix rangesBaseAddress DICompileUnit bitcode serialization/deserialization
Follow-up to r346788 review feedback from Adrian Prantl.
2019-12-27 17:26:14 -08:00
Kristina Bessonova cdd25a4c74 [DebugInfo][SelectionDAG] Change order while transferring SDDbgValue to another node
SelectionDAG::transferDbgValues() can 'reattach' SDDbgValue from one to
another node, but doesn't change its source order. If the destination node has
the order greater than the SDDbgValue, there are two possible issues
revealed later:

* If debug info is attached to an instruction that is the first definition
of a register, this ends up with a def-after-use and the debug info
gets 'undef' later.

* If MIR has another definition of a register above the debug info,
the debug info may represent a source variable incorrectly because
it appears (significantly) before an instruction corresponded
to this debug info.

So, the patch changes the order of an SDDbgValue when it is moved
to a node with greater order.

Reviewers: dblaikie, jmorse, aprantl

Reviewed By: aprantl

Subscribers: aprantl, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71175
2019-12-26 21:01:59 +03:00
Fangrui Song a36ddf0aa9 Migrate function attribute "no-frame-pointer-elim"="false" to "frame-pointer"="none" as cleanups after D56351 2019-12-24 16:27:51 -08:00
Fangrui Song eb16435b5e Migrate function attribute "no-frame-pointer-elim-non-leaf" to "frame-pointer"="non-leaf" as cleanups after D56351 2019-12-24 16:05:15 -08:00
Fangrui Song 502a77f125 Migrate function attribute "no-frame-pointer-elim" to "frame-pointer"="all" as cleanups after D56351 2019-12-24 15:57:33 -08:00
David Blaikie fccac1ec16 DebugInfo: Correct the form of DW_AT_macro_info in .dwo files (sec_offset, rather than data4) 2019-12-24 01:23:21 -08:00
Sourabh Singh Tomar 0a72515d33 [DebugInfo] Fix v4 macinfo for dwo files.
Dwo files must contain have DW_AT_macro_info attribute, when macro information is emitted. Adjusted the test case
for the same.
2019-12-24 12:50:34 +05:30
Igor Kudrin 6f635f9092 [DWARF] Check that all fields of a Unit Header are read.
Tests "dwarfdump-rnglists-dwarf64.s" and "dwarfdump-rnglists.s" were
malformed because they had missing required DWO ID fields in split
compilation unit headers. The patch fixes the tests and checks
the reading of a unit header more thoroughly.

Differential Revision: https://reviews.llvm.org/D71704
2019-12-24 09:38:20 +07:00
Vedant Kumar fa4701e197 [DWARF] Defer creating declaration DIEs until we prepare call site info
It isn't necessary to create DIEs for all of the declaration subprograms
in a CU's retainedTypes list. We can defer creating these subprograms
until we need to prepare a call site tag that refers to one.

This cleanup was mentioned in passing in D70350.
2019-12-20 15:26:31 -08:00
Vedant Kumar 79daafc903 Reland: [DWARF] Allow cross-CU references of subprogram definitions
This allows a call site tag in CU A to reference a callee DIE in CU B
without resorting to creating an incomplete duplicate DIE for the callee
inside of CU A.

We already allow cross-CU references of subprogram declarations, so it
doesn't seem like definitions ought to be special.

This improves entry value evaluation and tail call frame synthesis in
the LTO setting. During LTO, it's common for cross-module inlining to
produce a call in some CU A where the callee resides in a different CU,
and there is no declaration subprogram for the callee anywhere. In this
case llvm would (unnecessarily, I think) emit an empty DW_TAG_subprogram
in order to fill in the call site tag. That empty 'definition' defeats
entry value evaluation etc., because the debugger can't figure out what
it means.

As a follow-up, maybe we could add a DWARF verifier check that a
DW_TAG_subprogram at least has a DW_AT_name attribute.

Update:

Reland with a fix to create a declaration DIE when the declaration is
missing from the CU's retainedTypes list. The declaration is left out
of the retainedTypes list in two cases:

1) Re-compiling pre-r266445 bitcode (in which declarations weren't added
   to the retainedTypes list), and
2) Doing LTO function importing (which doesn't update the retainedTypes
   list).

It's possible to handle (1) and (2) by modifying the retainedTypes list
(in AutoUpgrade, or in the LTO importing logic resp.), but I don't see
an advantage to doing it this way, as it would cause more DWARF to be
emitted compared to creating the declaration DIEs lazily.

Tested with a stage2 ThinLTO+RelWithDebInfo build of clang, and with a
ReleaseLTO-g build of the test suite.

rdar://46577651, rdar://57855316, rdar://57840415

Differential Revision: https://reviews.llvm.org/D70350
2019-12-20 15:26:31 -08:00
Yury Delendik adf7a0a558 [WebAssembly] Use TargetIndex operands in DbgValue to track WebAssembly operands locations
Extends DWARF expression language to express locals/globals locations. (via
target-index operands atm) (possible variants are: non-virtual registers
or address spaces)

The WebAssemblyExplicitLocals can replace virtual registers to targertindex
operand type at the time when WebAssembly backend introduces
{get,set,tee}_local instead of corresponding virtual registers.

Reviewed By: aprantl, dschuff

Tags: #debug-info, #llvm

Differential Revision: https://reviews.llvm.org/D52634
2019-12-20 14:39:05 -08:00
Adrian Prantl 44b4b833ad Rename DW_AT_LLVM_isysroot to DW_AT_LLVM_sysroot
This is a purely cosmetic change that is NFC in terms of the binary
output. I bugs me that I called the attribute DW_AT_LLVM_isysroot
since the "i" is an artifact of GCC command line option syntax
(-isysroot is in the category of -i options) and doesn't carry any
useful information otherwise.

This attribute only appears in Clang module debug info.

Differential Revision: https://reviews.llvm.org/D71722
2019-12-20 13:11:17 -08:00
Evgenii Stepanov b538a2aa07 llvm-symbolizer: support DW_FORM_loclistx locations.
Summary:
With -gdwarf-5 local variable locations are emitted as DW_FORM_loclistx
form instead of the regular DW_FORM_sec_offset. Teach
DWARFDie::getLocations to understand the new format and use it in
llvm-symbolizer "FRAME" command.

Reviewers: pcc, jdoerfert

Subscribers: srhines, aprantl, hiraditya, rupprecht, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70756
2019-12-20 10:36:14 -08:00
Tom Weaver 453dc4d7ec [OPT-DBG] Teach DbgEntityHistoryCalculator about meta-instructions.
The calculator was considering instructions such as KILLs as clobbers
of a physical address. This is wrong as meta instructions such as KILLs
produce no output in the final program and thus don't clobber or change
any physical location's value. As a result they're safe to ignore whilst
calculating location list ranges.

reviewers: aprantl, vsk

diff revision: https://reviews.llvm.org/D70497

fixes: https://bugs.llvm.org/show_bug.cgi?id=38753
2019-12-20 14:03:34 +00:00
David Blaikie 97b5d6bfdc DebugInfo: Fix test fallout from aaa5a5e7ff 2019-12-18 19:00:40 -08:00
David Blaikie aaa5a5e7ff DebugInfo: Include DW_AT_base_addr even in gmlt with no inline functions
Since the address pool doesn't get populated in this case (due to the
lack of inlining, no child DIEs are added to the CU - so no addresses
are needed for the DIEs themselves) until the range list is emitted - at
the time the attributes are added to the CU, the address pool is empty.
So check whether the address pool will be used for the range lists & add
an addr_base if that's the case.
2019-12-18 17:14:28 -08:00
stozer 89d19d60ad Reapply: [DebugInfo] Correctly handle salvaged casts and split fragments at ISel
This reverts commit 1f3dd83cc1, reapplying
commit bb1b0bc4e5.

The original commit failed on some builds seemingly due to the use of a
bracketed constructor with an std::array, i.e. `std::array<> arr({...})`.
2019-12-18 16:26:42 +00:00
stozer 1f3dd83cc1 Revert "[DebugInfo] Correctly handle salvaged casts and split fragments at ISel"
Reverted due to build failure on windows bots.

This reverts commit bb1b0bc4e5.
2019-12-18 11:46:10 +00:00
stozer bb1b0bc4e5 [DebugInfo] Correctly handle salvaged casts and split fragments at ISel
Previously, LLVM had no functional way of performing casts inside of a
DIExpression(), which made salvaging cast instructions other than Noop
casts impossible. This patch enables the salvaging of casts by using the
DW_OP_LLVM_convert operator for SExt and Trunc instructions.

There is another issue which is exposed by this fix, in which fragment
DIExpressions (which are preserved more readily by this patch) for
values that must be split across registers in ISel trigger an assertion,
as the 'split' fragments extend beyond the bounds of the fragment
DIExpression causing an error. This patch also fixes this issue by
checking the fragment status of DIExpressions which are to be split, and
dropping fragments that are invalid.
2019-12-18 11:09:18 +00:00
Sourabh Singh Tomar 399273e5eb Recommit "[DebugInfo] Refactored macro related generation,
added a test case for macinfo.dwo emission."

This was reverted in caa4120906,
since it was causing an assertion failure on Windows bots.
This revision is revised to fix that.

Original commit message -

[DebugInfo] Refactored macro related generation, added a test case for macinfo.dwo emission.

Reviewers: dblaikie, aprantl, jini.susan.george

Tags: #debug-info #llvm

Differential Revision: https://reviews.llvm.org/D71008
2019-12-18 02:12:59 +05:30
Raphael Isemann ccfab8e459 [ObjC][DWARF] Emit DW_AT_APPLE_objc_direct for methods marked as __attribute__((objc_direct))
Summary:
With DWARF5 it is no longer possible to distinguish normal methods and methods with `__attribute__((objc_direct))` by just looking at the debug information
as they are both now children of the of the DW_TAG_structure_type that defines them (before only the `__attribute__((objc_direct))` methods were children).

This means that in LLDB we are no longer able to create a correct Clang AST of a module by just looking at the debug information. Instead we would
need to call the Objective-C runtime to see which of the methods have a `__attribute__((objc_direct))` and then add the attribute to our own Clang AST
depending on what the runtime returns. This would mean that we either let the module AST be dependent on the Objective-C runtime (which doesn't
seem right) or we retroactively add the missing attribute to the imported AST in our expressions.

A third option is to annotate methods with `__attribute__((objc_direct))` as `DW_AT_APPLE_objc_direct` which is what this patch implements. This way
LLDB doesn't have to call the runtime for any `__attribute__((objc_direct))` method and the AST in our module will already be correct when we create it.

Reviewers: aprantl, SouraVX

Reviewed By: aprantl

Subscribers: hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm, #debug-info

Differential Revision: https://reviews.llvm.org/D71201
2019-12-17 09:40:36 +01:00
Bjorn Pettersson e5f07080b8 [BasicBlockUtils] Fix dbg.value elimination problem in MergeBlockIntoPredecessor
Summary:
In commit d60f34c20a (llvm-svn 317128,
PR35113) MergeBlockIntoPredecessor was changed into
discarding some dbg.value intrinsics referring to
PHI values, post-splice due to loop rotation.

That elimination of dbg.value intrinsics did not
consider which dbg.value to keep depending on the
context (e.g. if the variable is changing its value
several times inside the basic block).

In the past that hasn't been such a big problem since
CodeGenPrepare::placeDbgValues has moved the dbg.value
to be next to the PHI node anyway. But after commit
00e238896c CodeGenPrepare isn't doing that
any longer, so we need to be more careful when avoiding
duplicate dbg.value intrinsics in MergeBlockIntoPredecessor.

This patch replaces the code that tried to avoid duplicate
dbg.values by using the RemoveRedundantDbgInstrs helper.

Reviewers: aprantl, jmorse, vsk

Reviewed By: aprantl, vsk

Subscribers: jholewinski, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71480
2019-12-16 11:41:21 +01:00
Fangrui Song a0aa58dad5 [AArch64] Save FP for leaf functions when disabling frame pointer elimination
The change allows clang -mno-omit-leaf-frame-pointer to disable frame
pointer elimination. This behavior matches X86 and Mips, and also GCC
AArch64.

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D71168
2019-12-13 18:48:58 -08:00
David Stenberg 5c7cc6f83d [LiveDebugValues] Omit entry values for DBG_VALUEs with pre-existing expressions
Summary:
This is a quickfix for PR44275. An assertion that checks that the
DIExpression is valid failed due to attempting to create an entry value
for an indirect parameter. This started appearing after D69028, as the
indirect parameter started being represented using an DW_OP_deref,
rather than with the DBG_VALUE's second operand, meaning that the
isIndirectDebugValue() check in LiveDebugValues did not exclude such
parameters. A DIExpression that has an entry value operation can
currently not have any other operation, leading to the failed isValid()
check.

This patch simply makes us stop considering emitting entry values
for such parameters. To support such cases I think we at least need
to do the following changes:

 * In DIExpression::isValid(): Remove the limitation that a
   DW_OP_LLVM_entry_value operation can be the only operation in a
   DIExpression.

 * In LiveDebugValues::emitEntryValues(): Create an entry value of size
   1, so that it only wraps the register operand, and not the whole
   pre-existing expression (the DW_OP_deref).

 * In LiveDebugValues::removeEntryValue(): Check that the new debug
   value has the same debug expression as the original, rather than
   checking that the debug expression is empty.

 * In DwarfExpression::addMachineRegExpression(): Modify the logic so
   that a DW_OP_reg* expression is emitted for the entry value.
   That is how GCC emits entry values for indirect parameters. That will
   currently not happen to due the DW_OP_deref causing the
   !HasComplexExpression to fail. The LocationKind needs to be changed
   also, rather than always emitting a DW_OP_stack_value for entry values.

There are probably more things I have missed, but that could hopefully
be a good starting point for emitting such entry values.

Reviewers: djtodoro, aprantl, jmorse, vsk

Reviewed By: aprantl, vsk

Subscribers: hiraditya, llvm-commits

Tags: #debug-info, #llvm

Differential Revision: https://reviews.llvm.org/D71416
2019-12-13 10:49:46 +01:00
Alexey Lapshin 71aaebc824 [DWARF5][DWARFVerifier] Check that Skeleton compilation unit does not have children.
That patch adds checking into DWARFVerifier that the Skeleton
compilation unit does not have children.

Differential Revision: https://reviews.llvm.org/D71244
2019-12-12 10:59:10 +03:00
Vedant Kumar 56232f950d Revert "[DWARF] Allow cross-CU references of subprogram definitions"
This reverts commit 30038da15b. It causes
the stage2 thinLTO bot to fail with:

Assertion failed: (CU.getDIE(CalleeSP) && "Expected declaration subprogram DIE for callee")

rdar://57840415
2019-12-11 15:55:48 -08:00
Nico Weber caa4120906 Revert "[DebugInfo] Refactored macro related generation, added a test case for macinfo.dwo emission."
This reverts commit 307f60a1a3.

DebugInfo/X86/debug-macinfo-split-dwarf.ll fails on Windows:

Command Output (stdout):
--
$ ":" "RUN: at line 1"
$ "c:\src\llvm-project\out\gn\bin\llc.exe" "-mtriple=x86_64-pc-windows-gnu" "-O0" "-split-dwarf-file=foo.dwo" "-filetype=obj"
Assertion failed: Section && "Cannot switch to a null section!", file ../../llvm/lib/MC/MCStreamer.cpp, line 1103
Stack dump:
0.	Program arguments: c:\src\llvm-project\out\gn\bin\llc.exe -mtriple=x86_64-pc-windows-gnu -O0 -split-dwarf-file=foo.dwo -filetype=obj
2019-12-10 21:32:30 -05:00
Vedant Kumar 30038da15b [DWARF] Allow cross-CU references of subprogram definitions
This allows a call site tag in CU A to reference a callee DIE in CU B
without resorting to creating an incomplete duplicate DIE for the callee
inside of CU A.

We already allow cross-CU references of subprogram declarations, so it
doesn't seem like definitions ought to be special.

This improves entry value evaluation and tail call frame synthesis in
the LTO setting. During LTO, it's common for cross-module inlining to
produce a call in some CU A where the callee resides in a different CU,
and there is no declaration subprogram for the callee anywhere. In this
case llvm would (unnecessarily, I think) emit an empty DW_TAG_subprogram
in order to fill in the call site tag. That empty 'definition' defeats
entry value evaluation etc., because the debugger can't figure out what
it means.

As a follow-up, maybe we could add a DWARF verifier check that a
DW_TAG_subprogram at least has a DW_AT_name attribute.

rdar://46577651

Differential Revision: https://reviews.llvm.org/D70350
2019-12-10 14:00:57 -08:00
Sourabh Singh Tomar 307f60a1a3 [DebugInfo] Refactored macro related generation, added a test case for macinfo.dwo emission.
Reviewers: dblaikie, aprantl, jini.susan.george

Tags: #debug-info #llvm

Differential Revision: https://reviews.llvm.org/D71008
2019-12-11 02:19:27 +05:30
Sourabh Singh Tomar fb4d8fe1a8 Recommit "[DWARF5] Start emitting DW_AT_dwo_name when -gdwarf-5 is specified."
Reviewers: dblaikie, aprantl, probinson

Tags: #debug-info #llvm

Differential Revision: https://reviews.llvm.org/D71185
2019-12-11 01:24:50 +05:30
Sourabh Singh Tomar d82b6ba21b Revert "[DWARF5] Start emitting DW_AT_dwo_name when -gdwarf-5 is specified."
This reverts commit 6ef01588f4.
Missing Differetial revision.
2019-12-11 01:20:40 +05:30
Sourabh Singh Tomar 6ef01588f4 [DWARF5] Start emitting DW_AT_dwo_name when -gdwarf-5 is specified. 2019-12-11 01:18:02 +05:30
Hans Wennborg 49da20ddb4 Revert 30e8f80fd5 "[DebugInfo] Don't create multiple DBG_VALUEs when sinking"
This caused non-determinism in the compiler, see command on the Phabricator
code review.

> This patch addresses a performance problem reported in PR43855, and
> present in the reapplication in in 001574938e5. It turns out that
> MachineSink will (often) move instructions to the first block that
> post-dominates the current block, and then try to sink further. This
> means if we have a lot of conditionals, we can needlessly create large
> numbers of DBG_VALUEs, one in each block the sunk instruction passes
> through.
>
> To fix this, rather than immediately sinking DBG_VALUEs, record them in
> a pass structure. When sinking is complete and instructions won't be
> sunk any further, new DBG_VALUEs are added, avoiding lots of
> intermediate DBG_VALUE $noregs being created.
>
> Differential revision: https://reviews.llvm.org/D70676
2019-12-10 19:20:11 +01:00
Jeremy Morse 00e238896c [DebugInfo] Nerf placeDbgValues, with prejudice
CodeGenPrepare::placeDebugValues moves variable location intrinsics to be
immediately after the Value they refer to. This makes tracking of locations
very easy; but it changes the order in which assignments appear to the
debugger, from the source programs order to the order in which the
optimised program computes values. This then leads to PR43986 and PR38754,
where variable locations that were in a conditional block are made
unconditional, which is highly misleading.

This patch adjusts placeDbgValues to only re-order variable location
intrinsics if they use a Value before it is defined, significantly reducing
the damage that it does. This is still not 100% safe, but the rest of
CodeGenPrepare needs polishing to correctly update debug info when
optimisations are performed to fully fix this.

This will probably break downstream debuginfo tests -- if the
instruction-stream position of variable location changes isn't the focus of
the test, an easy fix should be to manually apply placeDbgValues' behaviour
to the failing tests, moving dbg.value intrinsics next to SSA variable
definitions thus:

  %foo = inst1
  %bar = ...
  %baz = ...
  void call @llvm.dbg.value(metadata i32 %foo, ...

to

  %foo = inst1
  void call @llvm.dbg.value(metadata i32 %foo, ...
  %bar = ...
  %baz = ...

This should return your test to exercising whatever it was testing before.

Differential Revision: https://reviews.llvm.org/D58453
2019-12-09 12:52:10 +00:00
James Henderson dba420bc05 [test][tools] Add missing and improve testing
Mostly this adds testing for certain aliases in more explicit ways.
There are also a few tidy-ups, and additions of missing testing, where
the feature was either not tested at all, or not tested explicitly and
sufficiently.

Reviewed by: MaskRay, rupprecht, grimar

Differential Revision: https://reviews.llvm.org/D71116
2019-12-09 12:24:23 +00:00
David Stenberg 6965f835b4 [DebugInfo] Make describeLoadedValue() reg aware
Summary:
Currently the describeLoadedValue() hook is assumed to describe the
value of the instruction's first explicit define. The hook will not be
called for instructions with more than one explicit define.

This commit adds a register parameter to the describeLoadedValue() hook,
and invokes the hook for all registers in the worklist.

This will allow us to for example describe instructions which produce
more than two parameters' values; e.g. Hexagon's various combine
instructions.

This also fixes situations in our downstream target where we may pass
smaller parameters in the high part of a register. If such a parameter's
value is produced by a larger copy instruction, we can't describe the
call site value using the super-register, and we instead need to know
which sub-register that should be used.

This also allows us to handle cases like this:

  $ebx = [...]
  $rdi = MOVSX64rr32 $ebx
  $esi = MOV32rr $edi
  CALL64pcrel32 @call

The hook will first be invoked for the MOV32rr instruction, which will
say that @call's second parameter (passed in $esi) is described by $edi.
As $edi is not preserved it will be added to the worklist. When we get
to the MOVSX64rr32 instruction, we need to describe two values; the
sign-extended value of $ebx -> $rdi for the first parameter, and $ebx ->
$edi for the second parameter, which is now possible.

This commit modifies the dbgcall-site-lea-interpretation.mir test case.
In the test case, the values of some 32-bit parameters were produced
with LEA64r. Perhaps we can in general cases handle such by emitting
expressions that AND out the lower 32-bits, but I have not been able to
land in a case where a LEA64r is used for a 32-bit parameter instead of
LEA64_32 from C code.

I have not found a case where it would be useful to describe parameters
using implicit defines, so in this patch the hook is still only invoked
for explicit defines of forwarding registers.

Reviewers: djtodoro, NikolaPrica, aprantl, vsk

Reviewed By: djtodoro, vsk

Subscribers: ormris, hiraditya, llvm-commits

Tags: #debug-info, #llvm

Differential Revision: https://reviews.llvm.org/D70431
2019-12-09 10:47:49 +01:00
David Stenberg f3696533f2 Revert "[DebugInfo] Make describeLoadedValue() reg aware"
This reverts commit 3cd93a4efc.
I'll recommit with a well-formatted arcanist commit message.
2019-12-09 10:45:13 +01:00
David Stenberg 3cd93a4efc [DebugInfo] Make describeLoadedValue() reg aware
Currently the describeLoadedValue() hook is assumed to describe the
value of the instruction's first explicit define. The hook will not be
called for instructions with more than one explicit define.

This commit adds a register parameter to the describeLoadedValue() hook,
and invokes the hook for all registers in the worklist.

This will allow us to for example describe instructions which produce
more than two parameters' values; e.g. Hexagon's various combine
instructions.

This also fixes a case in our downstream target where we may pass
smaller parameters in the high part of a register. If such a parameter's
value is produced by a larger copy instruction, we can't describe the
call site value using the super-register, and we instead need to know
which sub-register that should be used.

This also allows us to handle cases like this:

  $ebx = [...]
  $rdi = MOVSX64rr32 $ebx
  $esi = MOV32rr $edi
  CALL64pcrel32 @call

The hook will first be invoked for the MOV32rr instruction, which will
say that @call's second parameter (passed in $esi) is described by $edi.
As $edi is not preserved it will be added to the worklist. When we get
to the MOVSX64rr32 instruction, we need to describe two values; the
sign-extended value of $ebx -> $rdi for the first parameter, and $ebx ->
$edi for the second parameter, which is now possible.

This commit modifies the dbgcall-site-lea-interpretation.mir test case.
In the test case, the values of some 32-bit parameters were produced
with LEA64r. Perhaps we can in general cases handle such by emitting
expressions that AND out the lower 32-bits, but I have not been able to
land in a case where a LEA64r is used for a 32-bit parameter instead of
LEA64_32 from C code.

I have not found a case where it would be useful to describe parameters
using implicit defines, so in this patch the hook is still only invoked
for explicit defines of forwarding registers.
2019-12-09 10:44:17 +01:00
Jeremy Morse 4650b2f369 Attempt to fix a debuginfo test that wasn't as generic as I thought
An ARM buildbot croaks when this test doesn't have a triple specified:

  http://lab.llvm.org:8011/builders/clang-cmake-armv7-quick/builds/12021/

Move the test to the X86 directory and put an x86_64 triple on the
llc command line.
2019-12-06 12:51:58 +00:00
Jeremy Morse c93a9b15ce [DebugInfo][CGP] Update dbg.values when sinking address computations
One of CodeGenPrepare's optimizations is to duplicate address calculations
into basic blocks, so that as much information as possible can be folded
into memory addressing operands. This is great -- but the dbg.value
variable location intrinsics are not updated in the same way. This can lead
to dbg.values referring to address computations in other blocks that will
never be encoded into the DAG, while duplicate address computations are
performed locally that could be used by the dbg.value. Some of these (such
as non-constant-offset GEPs) can't be salvaged past.

Fix this by, whenever we duplicate an address computation into a block,
looking for dbg.value users of the original memory address in the same
block, and redirecting those to the local computation.

Differential Revision: https://reviews.llvm.org/D58403
2019-12-06 11:27:19 +00:00
Jeremy Morse 30e8f80fd5 [DebugInfo] Don't create multiple DBG_VALUEs when sinking
This patch addresses a performance problem reported in PR43855, and
present in the reapplication in in 001574938e5. It turns out that
MachineSink will (often) move instructions to the first block that
post-dominates the current block, and then try to sink further. This
means if we have a lot of conditionals, we can needlessly create large
numbers of DBG_VALUEs, one in each block the sunk instruction passes
through.

To fix this, rather than immediately sinking DBG_VALUEs, record them in
a pass structure. When sinking is complete and instructions won't be
sunk any further, new DBG_VALUEs are added, avoiding lots of
intermediate DBG_VALUE $noregs being created.

Differential revision: https://reviews.llvm.org/D70676
2019-12-05 15:52:20 +00:00
Jeremy Morse e4cdd62631 [DebugInfo] Don't reorder DBG_VALUEs when sunk
Fix part of PR43855, resolving a problem that comes from the reapplication
in 001574938e5. If we have two DBG_VALUE insts in a block that specify
the location of the same variable, for example:

   %0 = someinst
   DBG_VALUE %0, !123, !DIExpression()
   %1 = anotherinst
   DBG_VALUE %1, !123, !DIExpression()

if %0 were to sink, the corresponding DBG_VALUE would sink too, past the
next DBG_VALUE, effectively re-ordering assignments. To fix this, I've
added a SeenDbgVars set recording what variable locations have been seen in
a block already (working bottom up), and now flag DBG_VALUEs that would
pass a later DBG_VALUE for the same variable.

NB, this only works for repeated DBG_VALUEs in the same basic block, the
general case involving control flow is much harder, which I've written
up in PR44117.

Differential revision: https://reviews.llvm.org/D70672
2019-12-05 15:52:20 +00:00
Jeremy Morse fca4100196 [DebugInfo] Re-apply two patches to MachineSink
These were:
 * D58386 / f5e1b718a6 / reverted in d382a8a768
 * D58238 / ee50590e16 / reverted in a8db456b53

Of which the latter has a performance regression tracked in PR43855,
fixed by D70672 / D70676, which will be committed atomically with this
reapplication.

Contains a minor difference to account for a change in the IsCopyInstr
signature.
2019-12-05 15:52:20 +00:00
Pavel Labath 4ee76a922a [llvm/DWARF] Return section offset from DWARFUnit::get{Loc,Rng}listOffset
Summary:
Currently these function return the raw content of the appropriate table
header, which means they are relative to the DW_AT_{loc,rng}list_base,
and one has to relocate them in order to do anything.

This changes the functions to perform the relocation themselves, which
seems more clearer, particularly as they are sitting right next to the
find{Rng,Loc}listFromOffset functions, but one *cannot* simply take the
result of these functions and take pass them there.

The only effect of this patch is to change what value is dumped for the
DW_AT_ranges attribute, which I think is for the better, as previously
the values appeared to point into thin air.

(The main reason I am looking at this is because I was trying to
implement equivalent functionality in lldb's DWARFUnit, and was stumped
by this behavior.

Reviewers: dblaikie, JDevlieghere, aprantl

Subscribers: hiraditya, llvm-commits, SouraVX

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71006
2019-12-05 12:35:09 +01:00
David Stenberg 54682d871d [DebugInfo] Handle call site values for instructions before call bundle
Summary:
If a call is bundled then the code that looks for instructions that
produce parameter values would break when reaching the call's bundle
header, due to the `ifCall(/*AnyInBundle*/)` invocation returning true.

It is not enough to simply ignore bundle headers in the `isCall()`
invocation, as the bundle header may have defines of parameter registers
due to the call, meaning that such registers would incorrectly be
removed from the worklist. Therefore, do not look at bundle headers at
all.

Reviewers: djtodoro, NikolaPrica, aprantl, vsk

Reviewed By: aprantl, vsk

Subscribers: hiraditya, llvm-commits

Tags: #debug-info, #llvm

Differential Revision: https://reviews.llvm.org/D71024
2019-12-05 11:50:41 +01:00
Djordje Todorovic 4b4ede440a Reland "[LiveDebugValues] Introduce entry values of unmodified params"
Relanding this after resolving the cause of the test failure.
2019-12-05 11:10:49 +01:00
Petr Hosek 00e436f130 [llvm-symbolizer] Support debug file lookup using build ID
Build ID is a protocol for looking up debug files that's already
supported by various tools including debuggers. For example, when
locating debug files, gdb would check the following directories:

- /usr/lib/debug/.build-id/ab/cdef1234.debug
- /usr/bin/ls.debug
- /usr/bin/.debug/ls.debug
- /usr/lib/debug/usr/bin/ls.debug

llvm-symbolizer currently consults all of these except for build ID
based one. This patch implements support for build ID lookup. The
set of debug directories to search is specified by the new option:
--debug-file-directory, whose name matches the debug-file-directory
variable used by gdb for the same purpose.

Differential Revision: https://reviews.llvm.org/D70759
2019-12-04 15:07:56 -08:00
Alexey Lapshin 789e257ce0 [DWARF5][Debuginfo] Compilation unit type (DW_UT_skeleton) and root DIE (DW_TAG_compile_unit) do not match.
That patch fixes incompatible compilation unit type (DW_UT_skeleton) and root DIE (DW_TAG_compile_unit) error.

cat split-dwarf.cpp
int main()
{
  int a = 1;
  return 0;
}

clang++ -O -g -gsplit-dwarf -gdwarf-5 split-dwarf.cpp; llvm-dwarfdump --verify ./a.out | grep skeleton
error: Compilation unit type (DW_UT_skeleton) and root DIE (DW_TAG_compile_unit) do not match.

The fix is to change DW_TAG_compile_unit into DW_TAG_skeleton_unit when skeleton file is generated.

Differential Revision: https://reviews.llvm.org/D70880
2019-12-05 00:53:47 +03:00
Djordje Todorovic 409350deea Revert "[LiveDebugValues] Introduce entry values of unmodified params"
This reverts commit rG4cfceb910692 due to LLDB test failing.
2019-12-03 13:13:27 +01:00
Pavel Labath 1fbe8a82e1 [DWARF] Add support for parsing/dumping section indices in location lists
Summary:
This does exactly what it says on the box. The only small gotcha is the
section index computation for offset_pair entries, which can use either
the base address section, or the section from the offset_pair entry.
This is to support both the cases where the base address is relocated
(points to the base of the CU, typically), and the case where the base
address is a constant (typically zero) and relocations are on the
offsets themselves.

Reviewers: dblaikie, JDevlieghere, aprantl, SouraVX

Subscribers: hiraditya, llvm-commits, probinson

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70540
2019-12-03 11:48:28 +01:00
Djordje Todorovic 4cfceb9106 [LiveDebugValues] Introduce entry values of unmodified params
The idea is to remove front-end analysis for the parameter's value
modification and leave it to the value tracking system. Front-end in some
cases marks a parameter as modified even the line of code that modifies the
parameter gets optimized, that implies that this will cover more entry
values even. In addition, extending the support for modified parameters
will be easier with this approach.

Since the goal is to recognize if a parameter’s value has changed, the idea
at very high level is: If we encounter a DBG_VALUE other than the entry
value one describing the same variable (parameter), we can assume that the
variable’s value has changed and we should not track its entry value any
more. That would be ideal scenario, but due to various LLVM optimizations,
a variable’s value could be just moved around from one register to another
(and there will be additional DBG_VALUEs describing the same variable), so
we have to recognize such situation (otherwise, we will lose a lot of entry
values) and salvage the debug entry value.

Differential Revision: https://reviews.llvm.org/D68209
2019-12-03 11:01:45 +01:00
Sourabh Singh Tomar f1e3988aa6 Recommit "[DWARF5]Addition of alignment atrribute in typedef DIE."
This revision is revised to update Go-bindings and Release Notes.

The original commit message follows.

This patch, adds support for DW_AT_alignment[DWARF5] attribute, to be emitted with typdef DIE.
When explicit alignment is specified.

Patch by Awanish Pandey <Awanish.Pandey@amd.com>

Reviewers: aprantl, dblaikie, jini.susan.george, SouraVX, alok,
deadalinx

Differential Revision: https://reviews.llvm.org/D70111
2019-12-03 09:51:43 +05:30
Sourabh Singh Tomar 3f3d0f4f4b [DebugInfo] Support for debug_macinfo.dwo section in llvm and llvm-dwarfdump.
This patch adds support for debug_macinfo.dwo section[pre-standardized]
to llvm and llvm-dwarfdump.

Reviewers: probinson, dblaikie, aprantl, jini.susan.george, alok

Differential Revision: https://reviews.llvm.org/D70705

Tags: #debug-info #llvm
2019-12-03 08:54:12 +05:30
Fangrui Song cd9c915d2a [Object][RISCV][test] Improve DebugInfo/RISCV/relax-debug-frame.ll
Reviewed By: luismarques

Differential Revision: https://reviews.llvm.org/D70578
2019-11-26 09:16:55 -08:00
Jeremy Morse d9c9a4e48d [DebugInfo] Avoid register coalesing unsoundly changing DBG_VALUE locations
This is a re-land of D56151 / r364515 with a completely new implementation.

Once MIR code leaves SSA form and the liveness of a vreg is considered,
DBG_VALUE insts are able to refer to non-live vregs, because their
debug-uses do not contribute to liveness. This non-liveness becomes
problematic for optimizations like register coalescing, as they can't
``see'' the debug uses in the liveness analyses.

As a result registers get coalesced regardless of debug uses, and that can
lead to invalid variable locations containing unexpected values. In the
added test case, the first vreg operand of ADD32rr is merged with various
copies of the vreg (great for performance), but a DBG_VALUE of the
unmodified operand is blindly updated to the modified operand. This changes
what value the variable will appear to have in a debugger.

Fix this by changing any DBG_VALUE whose operand will be resurrected by
register coalescing to be a $noreg DBG_VALUE, i.e. give the variable no
location. This is an overapproximation as some coalesced locations are safe
(others are not) -- an extra domination analysis would be required to work
out which, and it would be better if we just don't generate non-live
DBG_VALUEs.

Differential Revision: https://reviews.llvm.org/D64630
2019-11-25 13:47:06 +00:00
OCHyams 2de23c8364 [DebugInfo@O2][Utils] Undef instead of delete dbg.values in helper func
Summary:
Related bug: https://bugs.llvm.org/show_bug.cgi?id=40648

Static helper function rewriteDebugUsers in Local.cpp deletes dbg.value
intrinsics when it cannot move or rewrite them, or salvage the deleted
instruction's value. It should instead undef them in this case.

This patch fixes that and I've added a test which covers the failing test
case in bz40648. I've updated the unit test Local.ReplaceAllDbgUsesWith
to check for this behaviour (and fixed a typo in the test which would
cause the old test to always pass).

Reviewers: aprantl, vsk, djtodoro, probinson

Reviewed By: vsk

Subscribers: hiraditya, llvm-commits

Tags: #debug-info, #llvm

Differential Revision: https://reviews.llvm.org/D70604
2019-11-25 10:55:14 +00:00
Luís Marques 7bf721e59c [Object][RISCV] Resolve R_RISCV_32_PCREL
Summary: Add support for resolving `R_RISCV_32_PCREL` relocations. Those aren't
actually resolved AFAIK, but support is still needed to avoid llvm-dwarfdump
errors. The use of these relocations was introduced in D66419 but the
corresponding resolving wasn't added then. The test adds a check that should
catch future unresolved relocations.

Reviewers: asb, lenary
Reviewed By: asb
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D70204
2019-11-21 23:34:05 +00:00
Adrian Prantl 5da385fb56 Fix an offset underflow bug in DwarfExpression when describing small values with subregisters
DwarfExpression::addMachineReg() knows how to build a larger register
that isn't expressible in DWARF by combining multiple
subregisters. However, if the entire value fits into just one
subregister, it would still emit the other subregisters, leading to
all sorts of inconsistencies down the line.

This patch fixes that by moving an already existing(!) check whether
the subregister's offset is before the end of the value to the right
place.

rdar://problem/57294211

Differential Revision: https://reviews.llvm.org/D70508
2019-11-20 17:07:54 -08:00
Djordje Todorovic 979592a6f7 [DebugInfo] Remove the DIFlagArgumentNotModified debug info flag
Due to changes in D68206, we remove the DIFlagArgumentNotModified
and its usage.

Differential Revision: https://reviews.llvm.org/D68207
2019-11-20 13:18:40 +01:00
Vedant Kumar 568db780bb [CGDebugInfo] Emit subprograms for decls when AT_tail_call is understood (reland with fixes)
Currently, clang emits subprograms for declared functions when the
target debugger or DWARF standard is known to support entry values
(DW_OP_entry_value & the GNU equivalent).

Treat DW_AT_tail_call the same way to allow debuggers to follow cross-TU
tail calls.

Pre-patch debug session with a cross-TU tail call:

```
  * frame #0: 0x0000000100000fa4 main`target at b.c:4:3 [opt]
    frame #1: 0x0000000100000f99 main`main at a.c:8:10 [opt]
```

Post-patch (note that the tail-calling frame, "helper", is visible):

```
  * frame #0: 0x0000000100000fa4 main`target at b.c:4:3 [opt]
    frame #1: 0x0000000100000f80 main`helper [opt] [artificial]
    frame #2: 0x0000000100000f99 main`main at a.c:8:10 [opt]
```

This was reverted in 5b9a072c because it attached declaration
subprograms to inlinable builtin calls, which interacted badly with the
MergeICmps pass. The fix is to not attach declarations to builtins.

rdar://46577651

Differential Revision: https://reviews.llvm.org/D69743
2019-11-19 12:49:27 -08:00
Vedant Kumar ba71ca3720 [DebugInfo] Describe size of spilled values in call site params
A call site parameter description of a memory operand needs to
unambiguously convey the size of the operand to prevent incorrect entry
value evaluation.

Thanks for David Stenberg for pointing this issue out!
2019-11-19 12:03:52 -08:00
Thomas Preud'homme a89ca4ae17 Fix PR44001: assert failure in getFunctionLocalOffsetAfterInsn
Summary:
Assert in getFunctionLocalOffsetAfterInsn() fails when processing a call
MachineInstr inside a bundle and compiling with debug info. This is
because labels are added by DwarfDebug::beginInstruction() which is
called for each top-level MI by EmitFunctionBody()'s for-loop iteration
but constructCallSiteEntryDIEs() which calls
getFunctionLocalOffsetAfterInsn() iterates over all MIs.

This commit modifies constructCallSiteEntryDIEs() to get the associated
bundle MI for call MIs inside a bundle and use that to when calling
getFunctionLocalOffsetAfterInsn() and getLabelAfterInsn(). It also skips
loop iterations for bundle MIs since the loop statements are concerned
with debug info for each physical instructions and bundles represent a
group of instructions. It also fix the comment about PCAddr since the
code is getting the return address and not the call address.

Reviewers: dstenb, vsk, aprantl, djtodoro, dblaikie, NikolaPrica

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70293
2019-11-19 11:23:11 +00:00
Sam McCall d27a16eb39 Revert "[DWARF5]Addition of alignment atrribute in typedef DIE."
This reverts commit 423f541c1a, which
breaks llvm-c ABI.
2019-11-18 15:53:22 +01:00
Pavel Labath dca2b36ba0 Re-commit "DWARF location lists: Add section index dumping"
This reapplies c0f6ad7d1f with an
additional fix in test/DebugInfo/X86/constant-loclist.ll, which had a
slightly different output on windows targets. The test now accounts for
this difference.

The original commit message follows.

Summary:
As discussed in D70081, this adds the ability to dump section
names/indices to the location list dumper. It does this by moving the
range specific logic from DWARFDie.cpp:dumpRanges into the
DWARFAddressRange class.

The trickiest part of this patch is the backflip in the meanings of the
two dump flags for the location list sections.

The dumping of "raw" location list data is now controlled by
"DisplayRawContents" flag. This frees up the "Verbose" flag to be used
to control whether we print the section index. Additionally, the
DisplayRawContents flag is set for section-based dumps whenever the
--verbose option is passed, but this is not done for the "inline" dumps.

Also note that the index dumping currently does not work for the DWARF
v5 location lists, as the parser does not fill out the appropriate
fields. This will be done in a separate patch.

Reviewers: dblaikie, probinson, JDevlieghere, SouraVX

Subscribers: sdardis, hiraditya, jrtc27, atanasyan, arphaman, aprantl, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70227
2019-11-18 15:30:10 +01:00
Simon Pilgrim c070a27acc Revert rGc0f6ad7d1f3c : "DWARF location lists: Add section index dumping"
This reverts commit c0f6ad7d1f to fix the buildbots.
2019-11-18 13:26:51 +00:00
Pavel Labath c0f6ad7d1f DWARF location lists: Add section index dumping
Summary:
As discussed in D70081, this adds the ability to dump section
names/indices to the location list dumper. It does this by moving the
range specific logic from DWARFDie.cpp:dumpRanges into the
DWARFAddressRange class.

The trickiest part of this patch is the backflip in the meanings of the
two dump flags for the location list sections.

The dumping of "raw" location list data is now controlled by
"DisplayRawContents" flag. This frees up the "Verbose" flag to be used
to control whether we print the section index. Additionally, the
DisplayRawContents flag is set for section-based dumps whenever the
--verbose option is passed, but this is not done for the "inline" dumps.

Also note that the index dumping currently does not work for the DWARF
v5 location lists, as the parser does not fill out the appropriate
fields. This will be done in a separate patch.

Reviewers: dblaikie, probinson, JDevlieghere, SouraVX

Subscribers: sdardis, hiraditya, jrtc27, atanasyan, arphaman, aprantl, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70227
2019-11-18 10:50:22 +01:00
Sourabh Singh Tomar 423f541c1a [DWARF5]Addition of alignment atrribute in typedef DIE.
This patch, adds support for DW_AT_alignment[DWARF5] attribute, to be emitted with typdef DIE.
When explicit alignment is specified.

Patch by Awanish Pandey <Awanish.Pandey@amd.com>

Reviewers: aprantl, dblaikie, jini.susan.george, SouraVX, alok,
deadalinx

Differential Revision: https://reviews.llvm.org/D70111
2019-11-16 21:56:53 +05:30
David Blaikie d295087639 DebugInfo: Templatize rnglist header parsing to setup for reuse with loclist header parsing 2019-11-15 16:23:02 -08:00
Pavel Labath 0908093977 DWARFDebugLoc(v4): Add an incremental parsing function
Summary:
This adds a visitLocationList function to the DWARF v4 location lists,
similar to what already exists for DWARF v5. It follows the approach
outlined in previous patches (D69672), where the parsed form is always
stored in the DWARF v5 format, which makes it easier for generic code to
be built on top of that. v4 location lists are "upgraded" during
parsing, and then this upgrade is undone while dumping.

Both "inline" and section-based dumping is rewritten to reuse the
existing "generic" location list dumper. This means that the output
format is consistent for all location lists (the only thing one needs to
implement is the function which prints the "raw" form of a location
list), and that debug_loc dumping correctly processes base address
selection entries, etc.

The previous existing debug_loc functionality (e.g.,
parseOneLocationList) is rewritten on top of the new API, but it is not
removed as there is still code which uses them. This will be done in
follow-up patches, after I build the API to access the "interpreted"
location lists in a generic way (as that is what those users really
want).

Reviewers: dblaikie, probinson, JDevlieghere, aprantl, SouraVX

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69847
2019-11-15 13:38:00 +01:00
Vedant Kumar 1ee84e5ab2 [DebugInfo] Allow spill slots in call site parameter descriptions
Allow call site paramter descriptions to reference spill slots. Spill
slots are not visible to high-level LLVM IR, so they can safely be
referenced during entry value evaluation (as they cannot be clobbered by
some other function).

This gives a 5% increase in the number of call site parameter DIEs in an
LTO x86_64 build of the xnu kernel.

This reverts commit eb4c98ca3d (
[DebugInfo] Exclude memory location values as parameter entry values),
effectively reintroducing the portion of D60716 which dealt with memory
locations (authored by Djordje, Nikola, Ananth, and Ivan).

This partially addresses llvm.org/PR43343. However, not all memory
operands forwarded to callees live in spill slots. In the xnu build, it
may be possible to use an escape analysis to increase the number of call
site parameter by another 15% (more details in PR43343).

Differential Revision: https://reviews.llvm.org/D70254
2019-11-14 12:48:51 -08:00
Luís Marques c6b09bff56 [RISCV] Fix wrong CFI directives
Summary: Removes CFI CFA directives that could incorrectly propagate
beyond the basic block they were inteded for. Specifically it removes
the epilogue CFI directives. See the branch_and_tail_call test for an
example of the issue. Should fix the stack unwinding issues caused by
the incorrect directives.

Reviewers: asb, lenary, shiva0217
Reviewed By: lenary
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69723
2019-11-14 18:29:50 +00:00
Djordje Todorovic 2eb0862ed8 [AArch64][DebugInfo] Fix incorrect call site param value produced by MOVZXi
This resolves the problem with the truncation of the immediate operand.

Differential Revision: https://reviews.llvm.org/D70168
2019-11-14 11:02:35 +01:00
Pavel Labath eafe0cf5fa DWARFDebugLoclists: stricter base address handling
Summary:
This removes the use of zero as a base address in section-based dumping.
Although this will often be true for (unlinked) object files with a
single compile unit, it is not true in general. This means that
section-based dumping will not be able to resolve entries referencing
the base address (DW_LLE_offset_pair) -- it wasn't able to do that
correctly before either, but now it will be more explicit about it. One
exception to that is if the location list contains an explicit
DW_LLE_base_address entry -- in this case the dumper will pick it up,
and resolve subsequent entries normally.

The patch also removes the fallback to zero in the "inline" dumping in
case the compile unit does not contain a base address.

Reviewers: dblaikie, probinson, JDevlieghere, aprantl, SouraVX

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70115
2019-11-14 10:01:48 +01:00
David Stenberg 5e646ff530 [DebugInfo] Avoid creating entry values for clobbered registers
Summary:
Entry values are considered for parameters that have register-described
DBG_VALUEs in the entry block (along with other conditions).

If a parameter's value has been propagated from the caller to the
callee, then the parameter's DBG_VALUE in the entry block may be
described using a register defined by some instruction, and entry values
should not be emitted for the parameter, which can currently occur.
One such case was seen in the attached test case, in which the second
parameter, which is described by a redefinition of the first parameter's
register, would incorrectly get an entry value using the first
parameter's register. This commit intends to solve such cases by keeping
track of register defines, and ignoring DBG_VALUEs in the entry block
that are described by such registers.

In a RelWithDebInfo build of clang-8, the average size of the set was
27, and in a RelWithDebInfo+ASan build it was 30.

Reviewers: djtodoro, NikolaPrica, aprantl, vsk

Reviewed By: djtodoro, vsk

Subscribers: hiraditya, llvm-commits

Tags: #debug-info, #llvm

Differential Revision: https://reviews.llvm.org/D69889
2019-11-13 11:10:47 +01:00
Pavel Labath ebe2f56030 DWARFDebugLoclists: add location list "interpretation" logic
Summary:
This patch extracts the logic for computing the "absolute" locations,
which was partially present in the debug_loclists dumper, completes it,
and moves it into a separate function. This makes it possible to later
reuse the same logic for uses other than dumping.

The dumper is changed to reuse the location list interpreter, and its
format is changed somewhat. In "verbose" mode it prints the "raw" value
of a location list, the interpreted location (if available) and the
expression itself. In non-verbose mode it prints only one of the
location forms: it prefers the interpreted form, but falls back to the
"raw" format if interpretation is not possible (for instance, because we
were not given a base address, or the resolution of indirect addresses
failed).

This patch also undos some of the changes made in D69672, namely the
part about making all functions static. The main reason for this is that
I learned that the original approach (dumping only fully resolved
locations) meant that it was impossible to rewrite one of the existing
tests. To make that possible (and make the "inline location" dump work
in more cases), I now reuse the same dumping mechanism as is used for
section-based dumping. As this required having more objects know about
the various location lists classes, it seemed like a good idea to create
an interface abstracting the difference between them.

Therefore, I now create a DWARFLocationTable class, which will serve as
a base class for the location list classes. DWARFDebugLoclists is made
to inherit from that. DWARFDebugLoc will follow.

Another positive effect of this change is that section-based dumping
code will not need to use templates (as originally) envisioned, and that
the argument lists of the dumping functions become shorter.

Reviewers: dblaikie, probinson, JDevlieghere, aprantl, SouraVX

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70081
2019-11-12 10:40:13 +01:00
David Blaikie 736273c7fe DebugInfo: Do not create a debug_macinfo section if no CUs have associated macros
Patch based on Sourabh Singh's D69839 patch.
2019-11-08 15:30:11 -08:00
David Blaikie 3951245c38 NVPTX: Don't insert an extra empty line at the end of the last section.
This was arbitrarily appearing in only the last section emitted - which
made tests more sensitive than they needed to be (removing the last
section - like the macinfo section change that's coming after this)
would, surprisingly, move the blank line to the previous section.
2019-11-08 15:16:04 -08:00
David Blaikie 39c308f6b8 DebugInfo: Use separate macinfo contributions for each CU
The macinfo support was broken for LTO situations, by terminating
macinfo lists only once - multiple macinfo contributions were correctly
labeled, but they all continued/flowed into later contributions until
only one terminator appeared at the end of the section.

Correctly terminate each contribution & fix the parsing to handle this
situation too. The parsing fix is also necessary for dumping linked
binaries - the previous code would stop at the end of the first
contribution - missing all later contributions in a linked binary.

It'd be nice to improve the dumping to print the offsets of each
contribution so it'd be easier to know which CU AT_macro_info refers to
which macinfo contribution.
2019-11-08 13:27:00 -08:00
Hans Wennborg ff3b513495 Revert d91ed80 "[codeview] Reference types in type parent scopes"
This triggered asserts in the Chromium build, see https://crbug.com/1022729 for
details and reproducer.

> Without this change, when a nested tag type of any kind (enum, class,
> struct, union) is used as a variable type, it is emitted without
> emitting the parent type. In CodeView, parent types point to their inner
> types, and inner types do not point back to their parents. We already
> walk over all of the parent scopes to build the fully qualified name.
> This change simply requests their type indices as we go along to enusre
> they are all emitted.
>
> Fixes PR43905
>
> Reviewers: akhuang, amccarth
>
> Differential Revision: https://reviews.llvm.org/D69924
2019-11-08 11:30:33 +01:00
Reid Kleckner d91ed80e97 [codeview] Reference types in type parent scopes
Without this change, when a nested tag type of any kind (enum, class,
struct, union) is used as a variable type, it is emitted without
emitting the parent type. In CodeView, parent types point to their inner
types, and inner types do not point back to their parents. We already
walk over all of the parent scopes to build the fully qualified name.
This change simply requests their type indices as we go along to enusre
they are all emitted.

Fixes PR43905

Reviewers: akhuang, amccarth

Differential Revision: https://reviews.llvm.org/D69924
2019-11-07 13:58:01 -08:00
Hans Wennborg 5b9a072c39 Revert a5c8ec4 "[CGDebugInfo] Emit subprograms for decls when AT_tail_call is understood"
This caused Chromium builds to fail with "inlinable function call in a function
with debug info must have a !dbg location" errors. See
https://bugs.chromium.org/p/chromium/issues/detail?id=1022296#c1 for a
reproducer.

> Currently, clang emits subprograms for declared functions when the
> target debugger or DWARF standard is known to support entry values
> (DW_OP_entry_value & the GNU equivalent).
>
> Treat DW_AT_tail_call the same way to allow debuggers to follow cross-TU
> tail calls.
>
> Pre-patch debug session with a cross-TU tail call:
>
> ```
>   * frame #0: 0x0000000100000fa4 main`target at b.c:4:3 [opt]
>     frame #1: 0x0000000100000f99 main`main at a.c:8:10 [opt]
> ```
>
> Post-patch (note that the tail-calling frame, "helper", is visible):
>
> ```
>   * frame #0: 0x0000000100000fa4 main`target at b.c:4:3 [opt]
>     frame #1: 0x0000000100000f80 main`helper [opt] [artificial]
>     frame #2: 0x0000000100000f99 main`main at a.c:8:10 [opt]
> ```
>
> rdar://46577651
>
> Differential Revision: https://reviews.llvm.org/D69743
2019-11-07 10:30:07 +01:00
Pavel Labath e1f8c8a16f DWARFDebugLoclists: Move to a incremental parsing model
Summary:
This patch stems from the discussion D68270 (including some offline
talks). The idea is to provide an "incremental" api for parsing location
lists, which will avoid caching or materializing parsed data. An
additional goal is to provide a high level location list api, which
abstracts the differences between different encoding schemes, and can be
used by users which don't care about those (such as LLDB).

This patch implements the first part. It implements a call-back based
"visitLocationList" api. This function parses a single location list,
calling a user-specified callback for each entry. This is going to be
the base api, which other location list functions (right now, just the
dumping code) are going to be based on.

Future patches will do something similar for the v4 location lists, and
add a mechanism to translate raw entries into concrete address ranges.

Reviewers: dblaikie, probinson, JDevlieghere, aprantl, SouraVX

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69672
2019-11-06 16:25:06 +01:00
Vedant Kumar a5c8ec4baa [CGDebugInfo] Emit subprograms for decls when AT_tail_call is understood
Currently, clang emits subprograms for declared functions when the
target debugger or DWARF standard is known to support entry values
(DW_OP_entry_value & the GNU equivalent).

Treat DW_AT_tail_call the same way to allow debuggers to follow cross-TU
tail calls.

Pre-patch debug session with a cross-TU tail call:

```
  * frame #0: 0x0000000100000fa4 main`target at b.c:4:3 [opt]
    frame #1: 0x0000000100000f99 main`main at a.c:8:10 [opt]
```

Post-patch (note that the tail-calling frame, "helper", is visible):

```
  * frame #0: 0x0000000100000fa4 main`target at b.c:4:3 [opt]
    frame #1: 0x0000000100000f80 main`helper [opt] [artificial]
    frame #2: 0x0000000100000f99 main`main at a.c:8:10 [opt]
```

rdar://46577651

Differential Revision: https://reviews.llvm.org/D69743
2019-11-04 15:14:24 -08:00
Djordje Todorovic efacf2ce55 [test][DebugInfo] Add the test for ARM call site parameters
This is addition to D67556.

Patch by Nikola Prica
2019-10-31 14:45:50 +01:00
Jeremy Morse a8db456b53 Revert "[DebugInfo] MachineSink: Insert undef DBG_VALUEs when sinking instructions"
This reverts commit ee50590e16.

PR43855 reports a performance regression from this commit, which I'll
look into.
2019-10-31 12:39:06 +00:00
Jeremy Morse d382a8a768 Revert "[DebugInfo] MachineSink: find more DBG_VALUEs to sink"
This reverts commit f5e1b718a6.

PR43855 reports a performance regression with commit ee50590e. This commit
depends on the faulty one, so has to come out too.
2019-10-31 12:39:06 +00:00
Jeremy Morse 3137fe4d23 [DebugInfo][DAG] Distinguish different kinds of location indirection
From SelectionDAGs point of view, debug variable locations specified with
dbg.declare and dbg.addr are indirect -- they specify the address of
something. But calling conventions might mean that a Value is placed on
the stack somewhere, and this too is indirection. Previously this was
mixed up in the "IsIndirect" field of DBG_VALUE insts; this patch
separates them by encoding the indirection in a DIExpression.

If we have a dbg.declare or dbg.addr, then the expression produces an
address that then becomes a DWARF memory location. We can represent
this by putting a DW_OP_deref on the _end_ of the expression. If a Value
has been placed on the stack, then we need to put a DW_OP_deref on the
_start_ of the expression, to load the Value from the stack and have
the rest of the expression operate on it.

Differential Revision: https://reviews.llvm.org/D69028
2019-10-30 18:41:44 +00:00
Krzysztof Parzyszek 43144ffa91 LiveIntervals: Split live intervals on multiple dead defs
This is a follow-up to D67448.

Split live intervals with multiple dead defs during the initial
execution of the live interval analysis, but do it outside of the
function createAndComputeVirtRegInterval.

Differential Revision: https://reviews.llvm.org/D68666
2019-10-30 08:50:46 -05:00
Djordje Todorovic 532815dd5c [ARM][AArch64][DebugInfo] Improve call site instruction interpretation
Extend the describeLoadedValue() with support for target specific ARM and
AArch64 instructions interpretation. The patch provides specialization for
ADD and SUB operations that include a register and an immediate/offset
operand. Some of the instructions can operate with global string addresses
or constant pool indexes but such cases are omitted since we currently lack
flexible support for processing such operands at DWARF production stage.

Patch by Nikola Prica

Differential Revision: https://reviews.llvm.org/D67556
2019-10-30 13:58:14 +01:00
Adrian Prantl f919be3365 [DWARF5] Added support for deleted C++ special member functions.
This patch adds support for deleted C++ special member functions in
clang and llvm. Also added Defaulted member encodings for future
support for defaulted member functions.

Patch by Sourabh Singh Tomar!

Differential Revision: https://reviews.llvm.org/D69215
2019-10-29 13:44:06 -07:00
Sander de Smalen d6a7da80aa Reland [AArch64][DebugInfo] Do not recompute CalleeSavedStackSize (Take 2)
llvm/test/DebugInfo/MIR/X86/live-debug-values-reg-copy.mir failed with
EXPENSIVE_CHECKS enabled, causing the patch to be reverted in
rG2c496bb5309c972d59b11f05aee4782ddc087e71.

This patch relands the patch with a proper fix to the
live-debug-values-reg-copy.mir tests, by ensuring the MIR encodes the
callee-saves correctly so that the CalleeSaved info is taken from MIR
directly, rather than letting it be recalculated by the PEI pass. I've
done this by running `llc -stop-before=prologepilog` on the LLVM
IR as captured in the test files, adding the extra MOV instructions
that were manually added in the original test file, then running `llc
-run-pass=prologepilog` and finally re-added the comments for the MOV
instructions.
2019-10-29 16:13:07 +00:00
Simon Pilgrim 2c496bb530 Revert rG70f5aecedef9a6e347e425eb5b843bf797b95319 - "Reland [AArch64][DebugInfo] Do not recompute CalleeSavedStackSize (Take 2)"
This fails on EXPENSIVE_CHECKS builds
2019-10-29 11:54:58 +00:00
Sander de Smalen 70f5aecede Reland [AArch64][DebugInfo] Do not recompute CalleeSavedStackSize (Take 2)
Fixed up test/DebugInfo/MIR/Mips/live-debug-values-reg-copy.mir that
broke r375425.
2019-10-28 18:05:19 +00:00
Jeremy Morse f5e1b718a6 [DebugInfo] MachineSink: find more DBG_VALUEs to sink
In the Pre-RA machine sinker, previously we were relying on all DBG_VALUEs
being immediately after the instruction that defined their operands. This
isn't a valid assumption, as a variable location change doesn't
necessarily correspond to where the value is computed. In this patch, we
collect DBG_VALUEs that might need sinking as we walk through a block,
and sink all of them if their defining instruction is sunk.

This patch adds some copy propagation too, so that if we sink a copy inst,
the now non-dominated paths can use the copy source for the variable
location.

Differential Revision: https://reviews.llvm.org/D58386
2019-10-28 14:32:50 +00:00
Jeremy Morse ee50590e16 [DebugInfo] MachineSink: Insert undef DBG_VALUEs when sinking instructions
When we sink DBG_VALUEs between blocks, we simply move the DBG_VALUE
instruction to below the sunk instruction. However, we should also mark
the variable as being undef at the original location, to terminate any
earlier variable location. This patch does that -- plus, if the
instruction being sunk is a copy, it attempts to propagate the copy
through the DBG_VALUE, replacing the destination with the source.

Differential Revision: https://reviews.llvm.org/D58238
2019-10-28 12:17:56 +00:00
David Stenberg 74a72e6848 [DebugInfo] Stop describing imms in TargetInstrInfo's describeLoadedValue() impl
Summary:
The default implementation of the describeLoadedValue() hook uses the
MoveImm property to determine if an instruction moves an immediate. If
an instruction has that property the function returns the second
operand, assuming that that is the immediate value the instruction
moves. As far as I can tell, the MoveImm property does not imply that
the second operand is the immediate value, nor that any other operand
necessarily holds the immediate value; it just means that the
instruction moves some immediate value.

One example where the second operand is not the immediate is SystemZ's
LZER instruction, which moves a zero immediate implicitly: $f0S = LZER.

That case triggered an out-of-bound assertion when getting the operand.
I have added a test case for that instruction.

Another example is ARM's MVN instruction, which holds the logical
bitwise NOT'd value of the immediate that is moved. For the following
reproducer:

  extern void foo(int);
  int main() { foo(-11); }

an incorrect call site value would be emitted:

  $ clang --target=arm foo.c -O1 -g -Xclang -femit-debug-entry-values \
      -c -o - | ./build/bin/llvm-dwarfdump  - | \
      grep -A2 call_site_parameter

  0x00000058:       DW_TAG_GNU_call_site_parameter
                      DW_AT_location (DW_OP_reg0 R0)
                      DW_AT_GNU_call_site_value (DW_OP_lit10)

Another example is the A2_combineii instruction on Hexagon which moves
two immediates to a super-register: $d0 = A2_combineii 20, 10.

Perhaps these are rare exceptions, and most MoveImm instructions hold
the immediate in the second operand, but in my opinion the default
implementation of the hook should only describe values that it can, by
some contract, guarantee are safe to describe, rather than leaving it up
to the targets to override the exceptions, as that can silently result
in incorrect call site values.

This patch adds X86's relevant move immediate instructions to the
target's hook implementation, so this commit should be a NFC for that
target. We need to do the same for ARM and AArch64.

Reviewers: djtodoro, NikolaPrica, aprantl, vsk

Reviewed By: vsk

Subscribers: kristof.beyls, hiraditya, llvm-commits

Tags: #debug-info, #llvm

Differential Revision: https://reviews.llvm.org/D69109
2019-10-23 11:41:29 +02:00
Sander de Smalen 8f2dac471a Reverted r375425 as it broke some buildbots.
llvm-svn: 375444
2019-10-21 19:11:40 +00:00
Sander de Smalen 814548ec8e [AArch64][DebugInfo] Do not recompute CalleeSavedStackSize (Take 2)
Commit message from D66935:

This patch fixes a bug exposed by D65653 where a subsequent invocation
of `determineCalleeSaves` ends up with a different size for the callee
save area, leading to different frame-offsets in debug information.

In the invocation by PEI, `determineCalleeSaves` tries to determine
whether it needs to spill an extra callee-saved register to get an
emergency spill slot. To do this, it calls 'estimateStackSize' and
manually adds the size of the callee-saves to this. PEI then allocates
the spill objects for the callee saves and the remaining frame layout
is calculated accordingly.

A second invocation in LiveDebugValues causes estimateStackSize to return
the size of the stack frame including the callee-saves. Given that the
size of the callee-saves is added to this, these callee-saves are counted
twice, which leads `determineCalleeSaves` to believe the stack has
become big enough to require spilling an extra callee-save as emergency
spillslot. It then updates CalleeSavedStackSize with a larger value.

Since CalleeSavedStackSize is used in the calculation of the frame
offset in getFrameIndexReference, this leads to incorrect offsets for
variables/locals when this information is recalculated after PEI.

This patch fixes the lldb unit tests in `functionalities/thread/concurrent_events/*`

Changes after D66935:

Ensures AArch64FunctionInfo::getCalleeSavedStackSize does not return
the uninitialized CalleeSavedStackSize when running `llc` on a specific
pass where the MIR code has already been expected to have gone through PEI.

Instead, getCalleeSavedStackSize (when passed the MachineFrameInfo) will try
to recalculate the CalleeSavedStackSize from the CalleeSavedInfo. In debug
mode, the compiler will assert the recalculated size equals the cached
size as calculated through a call to determineCalleeSaves.

This fixes two tests:
  test/DebugInfo/AArch64/asan-stack-vars.mir
  test/DebugInfo/AArch64/compiler-gen-bbs-livedebugvalues.mir
that otherwise fail when compiled using msan.

Reviewed By: omjavaid, efriedma

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68783

llvm-svn: 375425
2019-10-21 17:12:56 +00:00
Adrian Prantl a9cfde1f6a [DWARF5] Added support for DW_AT_noreturn attribute to be emitted for
C++ class member functions.

Patch by Sourabh Singh Tomar!

Differential Revision: https://reviews.llvm.org/D68697

llvm-svn: 375012
2019-10-16 16:30:38 +00:00
David Stenberg 1ae2d9a2bd [DebugInfo] Add a DW_OP_LLVM_entry_value operation
Summary:
Internally in LLVM's metadata we use DW_OP_entry_value operations with
the same semantics as DWARF; that is, its operand specifies the number
of bytes that the entry value covers.

At the time of emitting entry values we don't know the emitted size of
the DWARF expression that the entry value will cover. Currently the size
is hardcoded to 1 in DIExpression, and other values causes the verifier
to fail. As the size is 1, that effectively means that we can only have
valid entry values for registers that can be encoded in one byte, which
are the registers with DWARF numbers 0 to 31 (as they can be encoded as
single-byte DW_OP_reg0..DW_OP_reg31 rather than a multi-byte
DW_OP_regx). It is a bit confusing, but it seems like llvm-dwarfdump
will print an operation "correctly", even if the byte size is less than
that, which may make it seem that we emit correct DWARF for registers
with DWARF numbers > 31. If you instead use readelf for such cases, it
will interpret the number of specified bytes as a DWARF expression. This
seems like a limitation in llvm-dwarfdump.

As suggested in D66746, a way forward would be to add an internal
variant of DW_OP_entry_value, DW_OP_LLVM_entry_value, whose operand
instead specifies the number of operations that the entry value covers,
and we then translate that into the byte size at the time of emission.

In this patch that internal operation is added. This patch keeps the
limitation that a entry value can only be applied to simple register
locations, but it will fix the issue with the size operand being
incorrect for DWARF numbers > 31.

Reviewers: aprantl, vsk, djtodoro, NikolaPrica

Reviewed By: aprantl

Subscribers: jyknight, fedor.sergeev, hiraditya, llvm-commits

Tags: #debug-info, #llvm

Differential Revision: https://reviews.llvm.org/D67492

llvm-svn: 374881
2019-10-15 11:31:21 +00:00
Jeremy Morse ed29dbaafa [DebugInfo] Remove some users of DBG_VALUEs IsIndirect field
This patch kills off a significant user of the "IsIndirect" field of
DBG_VALUE machine insts. Brought up in in PR41675, IsIndirect is
techncally redundant as it can be expressed by the DIExpression of a
DBG_VALUE inst, and it isn't helpful to have two ways of expressing
things.

Rather than setting IsIndirect, have DBG_VALUE creators add an extra deref
to the insts DIExpression. There should now be no appearences of
IsIndirect=True from isel down to LiveDebugVariables / VirtRegRewriter,
which is ensured by an assertion in LDVImpl::handleDebugValue. This means
we also get to delete the IsIndirect handling in LiveDebugVariables. Tests
can be upgraded by for example swapping the following IsIndirect=True
DBG_VALUE:

  DBG_VALUE $somereg, 0, !123, !DIExpression(DW_OP_foo)

With one where the indirection is in the DIExpression, by _appending_
a deref:

  DBG_VALUE $somereg, $noreg, !123, !DIExpression(DW_OP_foo, DW_OP_deref)

Which both mean the same thing. 

Most of the test changes in this patch are updates of that form; also some
changes in how the textual assembly printer handles these insts.

Differential Revision: https://reviews.llvm.org/D68945

llvm-svn: 374877
2019-10-15 10:46:24 +00:00
David Stenberg 8535bed795 [DebugInfo] Fix truncation of call site immediates
Summary:
This addresses a bug in collectCallSiteParameters() where call site
immediates would be truncated from int64_t to unsigned.

This fixes PR43525.

Reviewers: djtodoro, NikolaPrica, aprantl, vsk

Reviewed By: aprantl

Subscribers: hiraditya, llvm-commits

Tags: #debug-info, #llvm

Differential Revision: https://reviews.llvm.org/D68869

llvm-svn: 374770
2019-10-14 12:49:58 +00:00
David Blaikie 289c45cc62 DebugInfo: Use base address selection entries for debug_loc
Unify the range and loc emission (for both DWARFv4 and DWARFv5 style lists) and take advantage of that unification to use strategic base addresses for loclists.

Differential Revision: https://reviews.llvm.org/D68620

llvm-svn: 374600
2019-10-11 21:52:41 +00:00
David Blaikie f358c3d371 llvm-dwarfdump: Add verbose printing for debug_loclists
llvm-svn: 374582
2019-10-11 19:06:35 +00:00
Reid Kleckner 9d8f0b3519 [codeview] Try to avoid emitting .cv_loc with line zero
Summary:
Visual Studio doesn't like it while stepping. It kicks you out of the
source view of the file being stepped through and tries to fall back to
the disassembly view.

Fixes PR43530

The fix is incomplete, because it's possible to have a basic block with
no source locations at all. In this case, we don't emit a .cv_loc, but
that will result in wrong stepping behavior in the debugger if the
layout predecessor of the location-less BB has an unrelated source
location. We could try harder to find a valid location that dominates or
post-dominates the current BB, but in general it's a dataflow problem,
and one still might not exist. I left a FIXME about this.

As an alternative, we might want to consider having the middle-end check
if its emitting codeview and get it to stop using line zero.

Reviewers: akhuang

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68747

llvm-svn: 374267
2019-10-10 01:06:01 +00:00
Thomas Lively 00f9e5aa76 [WebAssembly] Make returns variadic
Summary:
This is necessary and sufficient to get simple cases of multiple
return working with multivalue enabled. More complex cases will
require block and loop signatures to be generalized to potentially be
type indices as well.

Reviewers: aheejin, dschuff

Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68684

llvm-svn: 374235
2019-10-09 21:42:08 +00:00
David Blaikie 411497c6c7 llvm-dwarfdump: Support multiple debug_loclists contributions
Also fixing the incorrect "offset" field being computed/printed for each
location list.

llvm-svn: 374232
2019-10-09 21:25:28 +00:00
Nikola Prica 98603a8153 [DebugInfo][If-Converter] Update call site info during the optimization
During the If-Converter optimization pay attention when copying or
deleting call instructions in order to keep call site information in
valid state.

Reviewers: aprantl, vsk, efriedma

Reviewed By: vsk, efriedma

Differential Revision: https://reviews.llvm.org/D66955

llvm-svn: 374068
2019-10-08 15:43:12 +00:00
Nikola Prica 02682498b8 [ISEL][ARM][AARCH64] Tracking simple parameter forwarding registers
Support for tracking registers that forward function parameters into the
following function frame. For now we only support cases when parameter
is forwarded through single register.

Reviewers: aprantl, vsk, t.p.northover

Reviewed By: vsk

Differential Revision: https://reviews.llvm.org/D66953

llvm-svn: 374033
2019-10-08 09:43:05 +00:00
Jeremy Morse 61800a75b7 [DebugInfo] LiveDebugValues: move DBG_VALUE creation into VarLoc class
Rather than having a mixture of location-state shared between DBG_VALUEs
and VarLoc objects in LiveDebugValues, this patch makes VarLoc the
master record of variable locations. The refactoring means that the
transfer of locations from one place to another is always a performed by
an operation on an existing VarLoc, that produces another transferred
VarLoc. DBG_VALUEs are only created at the end of LiveDebugValues, once
all locations are known. As a plus, there is now only one method where
DBG_VALUEs can be created.

The test case added covers a circumstance that is now impossible to
express in LiveDebugValues: if an already-indirect DBG_VALUE is spilt,
previously it would have been restored-from-spill as a direct DBG_VALUE.
We now don't lose this information along the way, as VarLocs always
refer back to the "original" non-transfer DBG_VALUE, and we can always
work out whether a location was "originally" indirect.

Differential Revision: https://reviews.llvm.org/D67398

llvm-svn: 373727
2019-10-04 10:53:47 +00:00
Jeremy Morse 0ca48de26c [DebugInfo] LiveDebugValues: defer DBG_VALUE creation during analysis
When transfering variable locations from one place to another,
LiveDebugValues immediately creates a DBG_VALUE representing that
transfer. This causes trouble if the variable location should
subsequently be invalidated by a loop back-edge, such as in the added
test case: the transfer DBG_VALUE from a now-invalid location is used
as proof that the variable location is correct. This is effectively a
self-fulfilling prophesy.

To avoid this, defer the insertion of transfer DBG_VALUEs until after
analysis has completed. Some of those transfers are still sketchy, but
we don't propagate them into other blocks now.

Differential Revision: https://reviews.llvm.org/D67393

llvm-svn: 373720
2019-10-04 09:38:05 +00:00
David Blaikie bfc68885d9 DebugInfo: Update support for detecting C++ language variants in debug info emission
llvm-svn: 373420
2019-10-02 01:39:48 +00:00
Djordje Todorovic eb4c98ca3d [DebugInfo] Exclude memory location values as parameter entry values
Abandon describing of loaded values due to safety concerns. Loaded
values are described as derefed memory location at caller point.
At callee we can unintentionally change that memory location which
would lead to different entry being printed value before and after
the memory location clobbering. This problem is described in
llvm.org/PR43343.

Patch by Nikola Prica

Differential Revision: https://reviews.llvm.org/D67717

llvm-svn: 373089
2019-09-27 13:52:43 +00:00
Pavel Labath aaff1a631a MCRegisterInfo: Merge getLLVMRegNum and getLLVMRegNumFromEH
Summary:
The functions different in two ways:
- getLLVMRegNum could return both "eh" and "other" dwarf register
  numbers, while getLLVMRegNumFromEH only returned the "eh" number.
- getLLVMRegNum asserted if the register was not found, while the second
  function returned -1.

The second distinction was pretty important, but it was very hard to
infer that from the function name. Aditionally, for the use case of
dumping dwarf expressions, we needed a function which can work with both
kinds of number, but does not assert.

This patch solves both of these issues by merging the two functions into
one, returning an Optional<unsigned> value. While the same thing could
be achieved by adding an "IsEH" argument to the (renamed)
getLLVMRegNumFromEH function, it seemed better to avoid the confusion of
two functions and put the choice of asserting into the hands of the
caller -- if he checks the Optional value, he can safely process
"untrusted" input, and if he blindly dereferences the Optional, he gets
the assertion.

I've updated all call sites to the new API, choosing between the two
options according to the function they were calling originally, except
that I've updated the usage in DWARFExpression.cpp to use the "safe"
method instead, and added a test case which would have previously
triggered an assertion failure when processing (incorrect?) dwarf
expressions.

Reviewers: dsanders, arsenm, JDevlieghere

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

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67154

llvm-svn: 372710
2019-09-24 09:31:02 +00:00
Adrian Prantl 0779dffbd4 Remove the obsolete BlockByRefStruct flag from LLVM IR
DIFlagBlockByRefStruct is an unused DIFlag that originally was used by
clang to express (Objective-)C block captures in debug info. For the
last year Clang has been emitting complex DIExpressions to describe
block captures instead, which makes all the code supporting this flag
redundant.

This patch removes the flag and all supporting "dead" code, so we can
reuse the bit for something else in the future.

Since this only affects debug info generated by Clang with the block
extension this mostly affects Apple platforms and I don't have any
bitcode compatibility concerns for removing this. The Verifier will
reject debug info that uses the bit and thus degrade gracefully when
LTO'ing older bitcode with a newer compiler.

rdar://problem/44304813

Differential Revision: https://reviews.llvm.org/D67453

llvm-svn: 372272
2019-09-18 22:38:56 +00:00
Krasimir Georgiev 2f1bba7fd0 Revert "[AArch64][DebugInfo] Do not recompute CalleeSavedStackSize"
Summary:
This reverts commit r372204.

This change causes build bot failures under msan:
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-fast/builds/35236/steps/check-llvm%20msan/logs/stdio:

```
FAIL: LLVM :: DebugInfo/AArch64/asan-stack-vars.mir (19531 of 33579)
******************** TEST 'LLVM :: DebugInfo/AArch64/asan-stack-vars.mir' FAILED ********************
Script:
--
: 'RUN: at line 1';   /b/sanitizer-x86_64-linux-fast/build/llvm_build_msan/bin/llc -O0 -start-before=livedebugvalues -filetype=obj -o - /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/test/DebugInfo/AArch64/asan-stack-vars.mir | /b/sanitizer-x86_64-linux-fast/build/llvm_build_msan/bin/llvm-dwarfdump -v - | /b/sanitizer-x86_64-linux-fast/build/llvm_build_msan/bin/FileCheck /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/test/DebugInfo/AArch64/asan-stack-vars.mir
--
Exit Code: 2

Command Output (stderr):
--
==62894==WARNING: MemorySanitizer: use-of-uninitialized-value
    #0 0xdfcafb in llvm::AArch64FrameLowering::resolveFrameOffsetReference(llvm::MachineFunction const&, int, bool, unsigned int&, bool, bool) const /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/Target/AArch64/AArch64FrameLowering.cpp:1658:3
    #1 0xdfae8a in resolveFrameIndexReference /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/Target/AArch64/AArch64FrameLowering.cpp:1580:10
    #2 0xdfae8a in llvm::AArch64FrameLowering::getFrameIndexReference(llvm::MachineFunction const&, int, unsigned int&) const /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/Target/AArch64/AArch64FrameLowering.cpp:1536
    #3 0x46642c1 in (anonymous namespace)::LiveDebugValues::extractSpillBaseRegAndOffset(llvm::MachineInstr const&) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/CodeGen/LiveDebugValues.cpp:582:21
    #4 0x4647cb3 in transferSpillOrRestoreInst /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/CodeGen/LiveDebugValues.cpp:883:11
    #5 0x4647cb3 in process /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/CodeGen/LiveDebugValues.cpp:1079
    #6 0x4647cb3 in (anonymous namespace)::LiveDebugValues::ExtendRanges(llvm::MachineFunction&) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/CodeGen/LiveDebugValues.cpp:1361
    #7 0x463ac0e in (anonymous namespace)::LiveDebugValues::runOnMachineFunction(llvm::MachineFunction&) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/CodeGen/LiveDebugValues.cpp:1415:18
    #8 0x4854ef0 in llvm::MachineFunctionPass::runOnFunction(llvm::Function&) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/CodeGen/MachineFunctionPass.cpp:73:13
    #9 0x53b0b01 in llvm::FPPassManager::runOnFunction(llvm::Function&) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/IR/LegacyPassManager.cpp:1648:27
    #10 0x53b15f6 in llvm::FPPassManager::runOnModule(llvm::Module&) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/IR/LegacyPassManager.cpp:1685:16
    #11 0x53b298d in runOnModule /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/IR/LegacyPassManager.cpp:1750:27
    #12 0x53b298d in llvm::legacy::PassManagerImpl::run(llvm::Module&) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/IR/LegacyPassManager.cpp:1863
    #13 0x905f21 in compileModule(char**, llvm::LLVMContext&) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/tools/llc/llc.cpp:601:8
    #14 0x8fdc4e in main /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/tools/llc/llc.cpp:355:22
    #15 0x7f67673632e0 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x202e0)
    #16 0x882369 in _start (/b/sanitizer-x86_64-linux-fast/build/llvm_build_msan/bin/llc+0x882369)

MemorySanitizer: use-of-uninitialized-value /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/Target/AArch64/AArch64FrameLowering.cpp:1658:3 in llvm::AArch64FrameLowering::resolveFrameOffsetReference(llvm::MachineFunction const&, int, bool, unsigned int&, bool, bool) const
Exiting
error: -: The file was not recognized as a valid object file
FileCheck error: '-' is empty.
FileCheck command line:  /b/sanitizer-x86_64-linux-fast/build/llvm_build_msan/bin/FileCheck /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/test/DebugInfo/AArch64/asan-stack-vars.mir
```

Reviewers: bkramer

Reviewed By: bkramer

Subscribers: sdardis, aprantl, kristof.beyls, jrtc27, atanasyan, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67710

llvm-svn: 372228
2019-09-18 14:42:09 +00:00
Sander de Smalen dc2a7f5b39 [AArch64][DebugInfo] Do not recompute CalleeSavedStackSize
This patch fixes a bug exposed by D65653 where a subsequent invocation
of `determineCalleeSaves` ends up with a different size for the callee
save area, leading to different frame-offsets in debug information.

In the invocation by PEI, `determineCalleeSaves` tries to determine
whether it needs to spill an extra callee-saved register to get an
emergency spill slot. To do this, it calls 'estimateStackSize' and
manually adds the size of the callee-saves to this. PEI then allocates
the spill objects for the callee saves and the remaining frame layout
is calculated accordingly.

A second invocation in LiveDebugValues causes estimateStackSize to return
the size of the stack frame including the callee-saves. Given that the
size of the callee-saves is added to this, these callee-saves are counted
twice, which leads `determineCalleeSaves` to believe the stack has
become big enough to require spilling an extra callee-save as emergency
spillslot. It then updates CalleeSavedStackSize with a larger value.

Since CalleeSavedStackSize is used in the calculation of the frame
offset in getFrameIndexReference, this leads to incorrect offsets for
variables/locals when this information is recalculated after PEI.

Reviewers: omjavaid, eli.friedman, thegameg, efriedma

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D66935

llvm-svn: 372204
2019-09-18 09:02:44 +00:00
Dmitri Gribenko 8a4595199a Revert "Fix test failures after r371640"
This reverts commit r371645, because r371640 was reverted.

llvm-svn: 371824
2019-09-13 08:26:59 +00:00
Vedant Kumar 0b91333d59 [DWARF] Emit call site parameter info when tuning for lldb
Emit debug entry values using standard DWARF5 opcodes when the debugger
tuning is set to lldb.

Differential Revision: https://reviews.llvm.org/D67410

llvm-svn: 371666
2019-09-11 21:23:39 +00:00
Matt Arsenault f5c3bb60b3 Fix test failures after r371640
r371640 evidently fixed bug 39481

llvm-svn: 371645
2019-09-11 18:55:20 +00:00
Guillaume Chatelet 48904e9452 [Alignment] Use llvm::Align in MachineFunction and TargetLowering - fixes mir parsing
Summary:
This catches malformed mir files which specify alignment as log2 instead of pow2.
See https://reviews.llvm.org/D65945 for reference,

This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: MatzeB, qcolombet, dschuff, arsenm, sdardis, nemanjai, jvesely, nhaehnle, hiraditya, kbarton, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, jsji, Petar.Avramovic, asbirlea, s.egerton, pzheng, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67433

llvm-svn: 371608
2019-09-11 11:16:48 +00:00
Reid Kleckner bf02399a85 [Windows] Replace TrapUnreachable with an int3 insertion pass
This is an alternative to D66980, which was reverted. Instead of
inserting a pseudo instruction that optionally expands to nothing, add a
pass that inserts int3 when appropriate after basic block layout.

Reviewers: hans

Differential Revision: https://reviews.llvm.org/D67201

llvm-svn: 371466
2019-09-09 23:04:25 +00:00
David Stenberg 5a583665f4 [DebugInfo][X86] Describe call site values for zero-valued imms
Summary:
Add zero-materializing XORs to X86's describeLoadedValue() hook in order
to produce call site values.

I have had to change the defs logic in collectCallSiteParameters() a bit
to be able to describe the XORs. The XORs implicitly define $eflags,
which would cause them to never be considered, due to a guard condition
that I->getNumDefs() is one. I have changed that condition so that we
now only consider instructions where a forwarded register overlaps with
the instruction's single explicit define. We still need to collect the implicit
defines of other forwarded registers to remove them from the work list.
I'm not sure how to move towards supporting instructions with multiple
explicit defines, cases where forwarded register are implicitly defined,
and/or cases where an instruction produces values for multiple forwarded
registers. Perhaps the describeLoadedValue() hook should take a register
argument, and we then leave it up to the hook to describe the loaded
value in that register? I have not yet encountered a situation where
that would be necessary though.

Reviewers: aprantl, vsk, djtodoro, NikolaPrica

Reviewed By: vsk

Subscribers: ychen, hiraditya, llvm-commits

Tags: #debug-info, #llvm

Differential Revision: https://reviews.llvm.org/D67225

llvm-svn: 371333
2019-09-08 14:22:06 +00:00
Bjorn Pettersson 2b698a13a1 [DwarfExpression] Disallow some rewrites to avoid undefined behavior
Summary:
The value operand in DW_OP_plus_uconst/DW_OP_constu value can be
large (it uses uint64_t as representation internally in LLVM).
This means that in the uint64_t to int conversions, previously done
by DwarfExpression::addMachineRegExpression, could lose information.
Also, the negation done in "-Offset" was undefined behavior in case
Offset was exactly INT_MIN.

To avoid the above problems, we now avoid transformation like
 [Reg, DW_OP_plus_uconst, Offset] --> [DW_OP_breg, Offset]
and
 [Reg, DW_OP_constu, Offset, DW_OP_plus]  --> [DW_OP_breg, Offset]
when Offset > INT_MAX.

And we avoid to transform
 [Reg, DW_OP_constu, Offset, DW_OP_minus] --> [DW_OP_breg,-Offset]
when Offset > INT_MAX+1.

The patch also adjusts DwarfCompileUnit::constructVariableDIEImpl
to make sure that "DW_OP_constu, Offset, DW_OP_minus" is used
instead of "DW_OP_plus_uconst, Offset" when creating DIExpressions
with negative frame index offsets.

Notice that this might just be the tip of the iceberg. There
are lots of fishy handling related to these constants. I think both
DIExpression::appendOffset and DIExpression::extractIfOffset may
trigger undefined behavior for certain values.

Reviewers: sdesmalen, rnk, JDevlieghere

Reviewed By: JDevlieghere

Subscribers: jholewinski, aprantl, hiraditya, ychen, uabelho, llvm-commits

Tags: #debug-info, #llvm

Differential Revision: https://reviews.llvm.org/D67263

llvm-svn: 371304
2019-09-07 11:40:10 +00:00
Bjorn Pettersson e85acf946d [DebugInfo] Pre-commit of test case for DW_OP_breg/DW_OP_fbreg folds
This currently triggers undefined behavior if executed with an
ubsan build. It is just a precommit of the test case to show that
we got a problem.

Fix is proposed in https://reviews.llvm.org/D67263 and plan is to
commit the fix directly after this patch.

llvm-svn: 371303
2019-09-07 11:39:57 +00:00
Jeremy Morse 5d9cd3b4ca [DebugInfo] LiveDebugValues: explicitly terminate overwritten stack locations
If a stack spill location is overwritten by another spill instruction,
any variable locations pointing at that slot should be terminated. We
cannot rely on spills always being restored to registers or variable
locations being moved by a DBG_VALUE: the register allocator is entitled
to spill a value and then forget about it when it goes out of liveness.

To address this, scan for memory writes to spill locations, even those we
don't consider to be normal "spills". isSpillInstruction and
isLocationSpill distinguish the two now. After identifying spill
overwrites, terminate the open range, and insert a $noreg DBG_VALUE for
that variable.

Differential Revision: https://reviews.llvm.org/D66941

llvm-svn: 371193
2019-09-06 10:08:22 +00:00
Guillaume Chatelet aff45e4b23 [LLVM][Alignment] Make functions using log of alignment explicit
Summary:
This patch renames functions that takes or returns alignment as log2, this patch will help with the transition to llvm::Align.
The renaming makes it explicit that we deal with log(alignment) instead of a power of two alignment.
A few renames uncovered dubious assignments:

 - `MirParser`/`MirPrinter` was expecting powers of two but `MachineFunction` and `MachineBasicBlock` were using deal with log2(align). This patch fixes it and updates the documentation.
 - `MachineBlockPlacement` exposes two flags (`align-all-blocks` and `align-all-nofallthru-blocks`) supposedly interpreted as power of two alignments, internally these values are interpreted as log2(align). This patch updates the documentation,
 - `MachineFunctionexposes` exposes `align-all-functions` also interpreted as power of two alignment, internally this value is interpreted as log2(align). This patch updates the documentation,

Reviewers: lattner, thegameg, courbet

Subscribers: dschuff, arsenm, jyknight, dylanmckay, sdardis, nemanjai, jvesely, nhaehnle, javed.absar, hiraditya, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, dexonsmith, PkmX, jocewei, jsji, Jim, s.egerton, llvm-commits, courbet

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65945

llvm-svn: 371045
2019-09-05 10:00:22 +00:00
Igor Kudrin e46639620d [DWARF] Fix referencing Range List Tables from CUs for DWARF64.
As DW_AT_rnglists_base points after the header and headers have
different sizes for DWARF32 and DWARF64, we have to use the format
of the CU to adjust the offset correctly in order to extract
the referenced range list table.

The patch also changes the type of RangeSectionBase because in DWARF64
it is 8-bytes long.

Differential Revision: https://reviews.llvm.org/D67098

llvm-svn: 371016
2019-09-05 07:02:28 +00:00
Alexey Lapshin cbf1f3b771 [Debuginfo][SROA] Need to handle dbg.value in SROA pass.
SROA pass processes debug info incorrecly if applied twice.
Specifically, after SROA works first time, instcombine converts dbg.declare
intrinsics into dbg.value. Inlining creates new opportunities for SROA,
so it is called again. This time it does not handle correctly previously
inserted dbg.value intrinsics.

Differential Revision: https://reviews.llvm.org/D64595

llvm-svn: 370906
2019-09-04 14:19:49 +00:00
Pavel Labath 98634c2e11 Fix address sizes in the dwarfdump-debug-loc-error-cases test
the test is building a 64-bit executable, so the addresses should be
64-bit too. The test was still passing even with smaller address size,
but it was hitting the "unexpected end of data" error sooner than it
should.

llvm-svn: 370882
2019-09-04 11:47:20 +00:00
Jeremy Morse 337a7cb55e [DebugInfo] LiveDebugValues: locations with different exprs should not be merged
When comparing variable locations, LiveDebugValues currently considers only
the machine location, ignoring any DIExpression applied to it. This is a
problem because that DIExpression can do pretty much anything to the machine
location, for example dereferencing it.

This patch adds DIExpressions to that comparison; now variables based on the
same register/memory-location but with different expressions will compare
differently, and be dropped if we attempt to merge them between blocks. This
reduces variable coverage-range a little, but only because we were producing
broken locations.

Differential Revision: https://reviews.llvm.org/D66942

llvm-svn: 370877
2019-09-04 11:09:05 +00:00
Pavel Labath 88b4e28a67 DWARF: Fix a regression in location list dumping
Summary:
While fixing the handling of some error cases, r370363 introduced new
problems -- assertion failures due to unchecked errors (my excuse is that a very
early version of that patch used Optional<T> instead of Expected).

This patch adds proper handling of parsing errors encountered when
dumping location lists from inside DWARF DIEs, and adds a bunch of
additional tests.

I reorder the arguments of the location list dumping functions to make
them consistent, and also be able to dump the two kinds of location
lists generically.

Reviewers: JDevlieghere, dblaikie, probinson

Subscribers: aprantl, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67102

llvm-svn: 370868
2019-09-04 10:09:12 +00:00
Reid Kleckner 3fa07dee94 Revert [Windows] Disable TrapUnreachable for Win64, add SEH_NoReturn
This reverts r370525 (git commit 0bb1630685)
Also reverts r370543 (git commit 185ddc08ee)

The approach I took only works for functions marked `noreturn`. In
general, a call that is not known to be noreturn may be followed by
unreachable for other reasons. For example, there could be multiple call
sites to a function that throws sometimes, and at some call sites, it is
known to always throw, so it is followed by unreachable. We need to
insert an `int3` in these cases to pacify the Windows unwinder.

I think this probably deserves its own standalone, Win64-only fixup pass
that runs after block placement. Implementing that will take some time,
so let's revert to TrapUnreachable in the mean time.

llvm-svn: 370829
2019-09-03 22:27:27 +00:00
Jeremy Morse 22493f66f1 [DebugInfo] LiveDebugValues: correctly discriminate kinds of variable locations
The missing line added by this patch ensures that only spilt variable
locations are candidates for being restored from the stack. Otherwise,
register or constant-value information can be interpreted as a spill
location, through a union.

The added regression test replicates a scenario where this occurs: the
stack load from [rsp] causes the register-location DBG_VALUE to be
"restored" to rsi, when it should be left alone. See PR43058 for details.

Un x-fail a test that was suffering from this from a previous patch.

Differential Revision: https://reviews.llvm.org/D66895

llvm-svn: 370648
2019-09-02 12:28:36 +00:00
Reid Kleckner 0bb1630685 [Windows] Disable TrapUnreachable for Win64, add SEH_NoReturn
Users have complained llvm.trap produce two ud2 instructions on Win64,
one for the trap, and one for unreachable. This change fixes that.

TrapUnreachable was added and enabled for Win64 in r206684 (April 2014)
to avoid poorly understood issues with the Windows unwinder.

There seem to be two major things in play:
- the unwinder
- C++ EH, _CxxFrameHandler3 & co

The unwinder disassembles forward from the return address to scan for
epilogues. Inserting a ud2 had the effect of stopping the unwinder, and
ensuring that it ran the EH personality function for the current frame.
However, it's not clear what the unwinder does when the return address
happens to be the last address of one function and the first address of
the next function.

The Visual C++ EH personality, _CxxFrameHandler3, needs to figure out
what the current EH state number is. It does this by consulting the
ip2state table, which maps from PC to state number. This seems to go
wrong when the return address is the last PC of the function or catch
funclet.

I'm not sure precisely which system is involved here, but in order to
address these real or hypothetical problems, I believe it is enough to
insert int3 after a call site if it would otherwise be the last
instruction in a function or funclet.  I was able to reproduce some
similar problems locally by arranging for a noreturn call to appear at
the end of a catch block immediately before an unrelated function, and I
confirmed that the problems go away when an extra trailing int3
instruction is added.

MSVC inserts int3 after every noreturn function call, but I believe it's
only necessary to do it if the call would be the last instruction. This
change inserts a pseudo instruction that expands to int3 if it is in the
last basic block of a function or funclet. I did what I could to run the
Microsoft compiler EH tests, and the ones I was able to run showed no
behavior difference before or after this change.

Differential Revision: https://reviews.llvm.org/D66980

llvm-svn: 370525
2019-08-30 20:46:39 +00:00
David Stenberg b35d4699d0 [LiveDebugValues] Insert entry values after bundles
Summary:
Change LiveDebugValues so that it inserts entry values after the bundle
which contains the clobbering instruction. Previously it would insert
the debug value after the bundle head using insertAfter(), breaking the
bundle.

Reviewers: djtodoro, NikolaPrica, aprantl, vsk

Reviewed By: vsk

Subscribers: hiraditya, llvm-commits

Tags: #debug-info, #llvm

Differential Revision: https://reviews.llvm.org/D66888

llvm-svn: 370448
2019-08-30 09:06:50 +00:00