Commit Graph

991 Commits

Author SHA1 Message Date
Jonas Devlieghere 8acb74e01f [MC] Report fatal error for DWARF types for non-ELF object files
Getting the DWARF types section is only implemented for ELF object
files. We already disabled emitting debug types in clang (r337717), but
now we also report an fatal error (rather than crashing) when trying to
obtain this section in MC. Additionally we ignore the generate debug
types flag for unsupported target triples.

See PR38190 for more information.

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

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

Reviewers: aprantl, dblaikie, probinson

Reviewed by: dblaikie

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

llvm-svn: 338487
2018-08-01 05:48:06 +00:00
Wolfgang Pieb 9ea65082ff [DWARF v5] Reposting r337981, which was reverted in r337997 due to a test failure in debuginfo_tests.
The test failure was caused by the compiler not emitting a __debug_ranges section with DWARF 4 and
earlier when no ranges are needed. The test checks for the existence regardless.

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

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

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

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

Testing:

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

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

llvm-svn: 338069
2018-07-26 20:56:53 +00:00
Alex Lorenz 7d808c19ff Revert r337981: it breaks the debuginfo-tests
This commit caused a regression in the debuginfo-tests:

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

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

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

Reviewer: dblaikie

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

llvm-svn: 337981
2018-07-25 23:03:22 +00:00
Wolfgang Pieb 439801ba1d [DWARF v5] Refactor range lists dumping by using a more generic way of handling tables of lists.
The intent is to use it for location list tables as well. Change is almost NFC with the exception
of the spelling of some strings used during dumping (all lowercase now).

Reviewer: JDevlieghere

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

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

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

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

Reviewers: JDevlieghere, aprantl, dblaikie, echristo, probinson

Subscribers: llvm-commits

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

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

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

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

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

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

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

  DW_AT_APPLE_runtime_class       (0x10)

we now print

  DW_AT_APPLE_runtime_class       (DW_LANG_ObjC)

llvm-svn: 337011
2018-07-13 16:06:17 +00:00
Wolfgang Pieb fcf3810cf7 [DWARF v5] Generate range list tables into the .debug_rnglists section. No support for split DWARF
and no use of DW_FORM_rnglistx with the DW_AT_ranges attribute.

Reviewer: aprantl

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

llvm-svn: 336927
2018-07-12 18:18:21 +00:00
Gabor Buella da4a966e1c NFC - Various typo fixes in tests
llvm-svn: 336268
2018-07-04 13:28:39 +00:00
Mikael Holmen 42f7bc96dd [DebugInfo] Make sure all DBG_VALUEs' reguse operands have IsDebug property
Summary:
In some cases, these operands lacked the IsDebug property, which is meant to signal that
they should not affect codegen. This patch adds a check for this property in the
MachineVerifier and adds it where it was missing.

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

Patch by: JesperAntonsson

Reviewers: aprantl, rnk, echristo, javed.absar

Reviewed By: aprantl

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

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

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

For cases where we had e.g.

 DBG_VALUE 42
 [...]
 DBG_VALUE undef

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

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

Reviewers: aprantl

Reviewed By: aprantl

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

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

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

Reviewer: JDevlieghere

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

llvm-svn: 335188
2018-06-20 22:56:37 +00:00
Bjorn Pettersson 428caf988b Re-apply "[DebugInfo] Check size of variable in ConvertDebugDeclareToDebugValue"
This is r334704 (which was reverted in r334732) with a fix for
types like x86_fp80. We need to use getTypeAllocSizeInBits and
not getTypeStoreSizeInBits to avoid dropping debug info for
such types.

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

llvm-svn: 334830
2018-06-15 13:48:55 +00:00
Vedant Kumar 4a2798c934 Remove the test from r333801
In r333801 I added a test for a dump method that, for reasons I don't
understand, fails on an msvc bot:

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

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

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

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

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

Addresses PR21059 and PR25124.

Original author: fedor.sergeev

Reviewers: jyknight, espindola, fedor.sergeev

Reviewed By: jyknight

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

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

llvm-svn: 333726
2018-06-01 05:31:58 +00:00
Jonas Devlieghere 43dce3edbe [CodeView] Add prefix to CodeView registers.
Adds CVReg to CodeView register names to prevent a duplicate symbol with
CR3 defined in termios.h, as suggested by Zachary on the mailing list.

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

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

rdar://39863705

llvm-svn: 333421
2018-05-29 14:35:34 +00:00
Vedant Kumar 40399a213d [DebugInfo] Maintain DI when converting GEP to bitcast
When a GEP with all zero indices is converted to bitcast, its DI wasn't
copied over to the newly created instruction. This patch fixes that bug.

Patch by Kareem Ergawy!

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

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

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

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

llvm-svn: 333138
2018-05-23 22:50:45 +00:00
Paul Robinson 543c0e1d50 [DWARFv5] Put the DWO ID in its place.
In DWARF v5, the DWO ID is in the (split/skeleton) CU header, not an
attribute on the CU DIE.

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

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

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

Test Plan: check-llvm, just in case

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

rdar://problem/38513870

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

llvm-svn: 332873
2018-05-21 19:36:54 +00:00
Wolfgang Pieb ad60559be7 [DWARF v5] Improved support for .debug_rnglists (consumer). Enables any consumer to
extract DWARF v5 encoded rangelists.

Reviewer: JDevlieghere

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

llvm-svn: 332759
2018-05-18 20:12:54 +00:00
Wolfgang Pieb f2b6915ed4 [DWARF] Fixing a bug in DWARF v5 string offsets tables where the length encoded the contribution
length excluding the table header. Instead it must encode the contribution length minus the length
field itself.

Reviewer: JDevliegehere

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

llvm-svn: 332030
2018-05-10 20:02:34 +00:00
James Henderson a3acf99e59 [DWARF] Rework debug line parsing to use llvm::Error and callbacks
Reviewed by: dblaikie, JDevlieghere, espindola

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

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

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

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

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

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

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

llvm-svn: 331971
2018-05-10 10:51:33 +00:00
Shiva Chen 2c864551df [DebugInfo] Add DILabel metadata and intrinsic llvm.dbg.label.
In order to set breakpoints on labels and list source code around
labels, we need collect debug information for labels, i.e., label
name, the function label belong, line number in the file, and the
address label located. In order to keep these information in LLVM
IR and to allow backend to generate debug information correctly.
We create a new kind of metadata for labels, DILabel. The format
of DILabel is

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

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

llvm.dbg.label(metadata !1)

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

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

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

Patch by Hsiangkai Wang.

llvm-svn: 331841
2018-05-09 02:40:45 +00:00
Adrian Prantl 3edc63a579 DwarfCompileUnit: Fix another assertion failure on malformed input
that is not rejected by the Verifier.

Thanks to Björn Pettersson for providing a reproducer!

llvm-svn: 331535
2018-05-04 16:10:43 +00:00
Bjorn Pettersson 304877e5ec Reapply "[SelectionDAG] Selection of DBG_VALUE using a PHI node result (pt 2)"
Summary:
This reverts SVN r331441 (reapplies r331337), together with a fix
in to handle an already existing fragment expression in the
dbg.value that must be fragmented due to a split PHI node.

This should solve the problem seen in PR37321, which was the
reason for the revert of r331337.

The situation in PR37321 is that we have a PHI node like this

   %u.sroa = phi i80 [ %u.sroa.x, %if.x ],
                     [ %u.sroa.y, %if.y ],
                     [ %u.sroa.z, %if.z ]

and a dbg.value like this

  call void @llvm.dbg.value(metadata i80 %u.sroa,
                            metadata !13,
                            metadata !DIExpression(DW_OP_LLVM_fragment, 0, 80))

The phi node is split into three 32-bit PHI nodes

  %30:gr32 = PHI %11:gr32, %bb.4, %14:gr32, %bb.5, %27:gr32, %bb.8
  %31:gr32 = PHI %12:gr32, %bb.4, %15:gr32, %bb.5, %28:gr32, %bb.8
  %32:gr32 = PHI %13:gr32, %bb.4, %16:gr32, %bb.5, %29:gr32, %bb.8

but since the original value only is 80 bits we need to adjust the size
of the last fragment expression, and with this patch we get

  DBG_VALUE debug-use %30:gr32, debug-use $noreg, !"u", !DIExpression(DW_OP_LLVM_fragment, 0, 32)
  DBG_VALUE debug-use %31:gr32, debug-use $noreg, !"u", !DIExpression(DW_OP_LLVM_fragment, 32, 32)
  DBG_VALUE debug-use %32:gr32, debug-use $noreg, !"u", !DIExpression(DW_OP_LLVM_fragment, 64, 16)

Reviewers: vsk, aprantl, mstorsjo

Reviewed By: aprantl

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D46384

llvm-svn: 331464
2018-05-03 17:04:16 +00:00
Martin Storsjo 67fdea490d Revert "[SelectionDAG] Selection of DBG_VALUE using a PHI node result (pt 2)"
This reverts SVN r331337, see PR37321 for details on the regression
it introduced.

llvm-svn: 331441
2018-05-03 07:09:33 +00:00
Bjorn Pettersson 1c5a05f32c [SelectionDAG] Selection of DBG_VALUE using a PHI node result (pt 2)
Summary:
This is a follow up to rL331182. A PHI node can be split up into
several MIR PHI nodes when being selected. When there is a
dbg.value intrinsic that uses the result of such a PHI node we
need to select several DBG_VALUE instructions, with fragment
expressions, in order to do a correct selection.

Reviewers: rnk, aprantl, vsk

Reviewed By: vsk

Subscribers: mattd, llvm-commits, JDevlieghere, aprantl, gbedwell, rnk

Tags: #debug-info

Differential Revision: https://reviews.llvm.org/D46329

llvm-svn: 331337
2018-05-02 06:56:38 +00:00
Bjorn Pettersson 9a8483a4b2 [BranchFolding] Salvage DBG_VALUE instructions from empty blocks
Summary:
This patch will introduce copying of DBG_VALUE instructions
from an otherwise empty basic block to predecessor/successor
blocks in case the empty block is eliminated/bypassed. It
is currently only done in one identified situation in the
BranchFolding pass, before optimizing on empty block.
It can be seen as a light variant of the propagation done
by the LiveDebugValues pass, which unfortunately is executed
after the BranchFolding pass.

We only propagate (copy) DBG_VALUE instructions in a limited
number of situations:
 a) If the empty BB is the only predecessor of a successor
    we can copy the DBG_VALUE instruction to the beginning of
    the successor (because the DBG_VALUE instruction is always
    part of the flow between the blocks).
 b) If the empty BB is the only successor of a predecessor
    we can copy the DBG_VALUE instruction to the end of the
    predecessor (because the DBG_VALUE instruction is always
    part of the flow between the blocks). In this case we add
    the DBG_VALUE just before the first terminator (assuming
    that the terminators do not impact the DBG_VALUE).

A future solution, to handle more situations, could perhaps
be to run the LiveDebugValues pass before branch folding?

This fix is related to PR37234. It is expected to resolve
the problem seen, when applied together with the fix in
SelectionDAG from here: https://reviews.llvm.org/D46129

Reviewers: #debug-info, aprantl, rnk

Reviewed By: #debug-info, aprantl

Subscribers: ormris, gbedwell, llvm-commits

Differential Revision: https://reviews.llvm.org/D46184

llvm-svn: 331183
2018-04-30 14:37:46 +00:00
Bjorn Pettersson abafca619b [SelectionDAG] Improve selection of DBG_VALUE using a PHI node result
Summary:
When building the selection DAG at ISel all PHI nodes are
selected and lowered to Machine Instruction PHI nodes before
we start to create any SDNodes. So there are no SDNodes for
values produced by the PHI nodes.

In the past when selecting a dbg.value intrinsic that uses
the value produced by a PHI node we have been handling such
dbg.value intrinsics as "dangling debug info". I.e. we have
not created a SDDbgValue node directly, because there is
no existing SDNode for the PHI result, instead we deferred
the creationg of a SDDbgValue until we found the first use
of the PHI result.

The old solution had a couple of flaws. The position of the
selected DBG_VALUE instruction would end up quite late in a
basic block, and for example not directly after the PHI node
as in the LLVM IR input. And in case there were no use at all
in the basic block the dbg.value could be dropped completely.

This patch introduces a new VREG kind of SDDbgValue nodes.
It is similar to a SDNODE kind of node, but it refers directly
to a virtual register and not a SDNode. When we do selection
for a dbg.value that is using the result of a PHI node we
can do a lookup of the virtual register directly (as it already
is determined for the PHI node) and create a SDDbgValue node
immediately instead of delaying the selection until we find a
use.

This should fix a problem with losing debug info at ISel
as seen in PR37234 (https://bugs.llvm.org/show_bug.cgi?id=37234).
It does not resolve PR37234 completely, because the debug info
is dropped later on in the BranchFolder (see D46184).

Reviewers: #debug-info, aprantl

Reviewed By: #debug-info, aprantl

Subscribers: rnk, gbedwell, aprantl, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D46129

llvm-svn: 331182
2018-04-30 14:37:39 +00:00
Adrian Prantl 4b542c6e64 Fix a bug that prevents global variables from having a DW_OP_deref.
For local variables the first DW_OP_deref is consumed by turning the
location kind into a memeory location, but that only makes sense for
values that are in a register to begin with, which cannot happen for
global variables that are attached to a symbol.

rdar://problem/39741860

This reapplies r330970 after fixing an uncovered bug in r331086 and
working around the situation caused by it.

llvm-svn: 331090
2018-04-27 22:05:31 +00:00
Adrian Prantl 855b91022d Revert "Fix a bug that prevents global variables from having a DW_OP_deref."
This reverts commit r3309704 while investigating bot breakage.

llvm-svn: 330993
2018-04-26 20:59:58 +00:00
Adrian Prantl e42805d07c Fix a bug that prevents global variables from having a DW_OP_deref.
For local variables the first DW_OP_deref is consumed by turning the
location kind into a memeory location, but that only makes sense for
values that are in a register to begin with, which cannot happen for
global variables that are attached to a symbol.

rdar://problem/39741860

llvm-svn: 330970
2018-04-26 18:17:04 +00:00
Francis Visoiu Mistrih 57fcd3454a [MIR] Add support for debug metadata for fixed stack objects
Debug var, expr and loc were only supported for non-fixed stack objects.

This patch adds the following fields to the "fixedStack:" entries, and
renames the ones from "stack:" to:

* debug-info-variable
* debug-info-expression
* debug-info-location

Differential Revision: https://reviews.llvm.org/D46032

llvm-svn: 330859
2018-04-25 18:58:06 +00:00
Andrew Ng 7a2fa74ab0 [DebugInfo] Use WithColor for more debug line warnings
Updated two more debug line related warnings to use WithColor. This was
necessary to ensure consistent output order of the warnings on Windows
for debug line tests.

Differential Revision: https://reviews.llvm.org/D45871

llvm-svn: 330440
2018-04-20 15:29:47 +00:00
Andrew Ng a6763bfd6d [DebugInfo] Fix for split dwarf test on Windows (NFC)
On Windows, %llc_dwarf automatically adds -mtriple causing this test to
error. Changed %llc_dwarf to llc.

Differential Revision: https://reviews.llvm.org/D45869

llvm-svn: 330414
2018-04-20 10:44:42 +00:00
Pavel Labath 10831f594a Fix macosx build broken by r330249
It seems llc crashes when targetting darwin with split-dwarf (pr37164).
This happens on all inputs, not just the one I added in the above
commit. Work around the issue by hardcoding the target triple to linux,
which is what all split-dwarf tests seem to be doing.

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

llvm-svn: 330265
2018-04-18 15:23:21 +00:00
Bjorn Pettersson bc4f19b6bd [DebugInfo] Sink related dbg users when sinking in InstCombine
Summary:
When sinking an instruction in InstCombine we now also sink
the DbgInfoIntrinsics that are using the sunken value.

Example)

When sinking the load in this input

bb.X:
  %0 = load i64, i64* %start, align 4, !dbg !31
  tail call void @llvm.dbg.value(metadata i64 %0, ...)
  br i1 %cond, label %for.end, label %for.body.lr.ph
for.body.lr.ph:
  br label %for.body

we now also move the dbg.value, like this

bb.X:
  br i1 %cond, label %for.end, label %for.body.lr.ph
for.body.lr.ph:
  %0 = load i64, i64* %start, align 4, !dbg !31
  tail call void @llvm.dbg.value(metadata i64 %0, ...)
  br label %for.body

In the past we haven't moved the dbg.value so we got

bb.X:
  tail call void @llvm.dbg.value(metadata i64 %0, ...)
  br i1 %cond, label %for.end, label %for.body.lr.ph
for.body.lr.ph:
  %0 = load i64, i64* %start, align 4, !dbg !31
  br label %for.body


So in the past we got a debug-use before the def of %0.
And that dbg.value was also on the path jumping to %for.end, for
which %0 never was defined.

CodeGenPrepare normally comes to rescue later (when not moving
the dbg.value), since it moves dbg.value instrinsics quite
brutally, without really analysing if it is correct to move
the intrinsic (see PR31878).
So at the moment this patch isn't expected to have much impact,
besides that it is moving the dbg.value already in opt, making
the IR look more sane directly.

This can be seen as a preparation to (hopefully) make it possible
to turn off CodeGenPrepare::placeDbgValues later as a solution
to PR31878.

I also adjusted test/DebugInfo/X86/sdagsplit-1.ll to make the
IR in the test case up-to-date with this behavior in InstCombine.

Reviewers: rnk, vsk, aprantl

Reviewed By: vsk, aprantl

Subscribers: mattd, JDevlieghere, llvm-commits

Tags: #debug-info

Differential Revision: https://reviews.llvm.org/D45425

llvm-svn: 330243
2018-04-18 08:08:04 +00:00
Roman Tereshin d769eb36ab [DebugInfo][OPT] Fixing a couple of DI duplication bugs of CloneModule
As demonstrated by the regression tests added in this patch, the
following cases are valid cases:

1. A Function with no DISubprogram attached, but various debug info
  related to its instructions, coming, for instance, from an inlined
  function, also defined somewhere else in the same module;
2. ... or coming exclusively from the functions inlined and eliminated
  from the module entirely.

The ValueMap shared between CloneFunctionInto calls within CloneModule
needs to contain identity mappings for all of the DISubprogram's to
prevent them from being duplicated by MapMetadata / RemapInstruction
calls, this is achieved via DebugInfoFinder collecting all the
DISubprogram's. However, CloneFunctionInto was missing calls into
DebugInfoFinder for functions w/o DISubprogram's attached, but still
referring DISubprogram's from within (case 1). This patch fixes that.

The fix above, however, exposes another issue: if a module contains a
DISubprogram referenced only indirectly from other debug info
metadata, but not attached to any Function defined within the module
(case 2), cloning such a module causes a DICompileUnit duplication: it
will be moved in indirecty via a DISubprogram by DebugInfoFinder first
(because of the first bug fix described above), without being
self-mapped within the shared ValueMap, and then will be copied during
named metadata cloning. So this patch makes sure DebugInfoFinder
visits DICompileUnit's referenced from DISubprogram's as it goes w/o
re-processing llvm.dbg.cu list over and over again for every function
cloned, and makes sure that CloneFunctionInto self-maps
DICompileUnit's referenced from the entire function, not just its own
DISubprogram attached that may also be missing.

The most convenient way of tesing CloneModule I found is to rely on
CloneModule call from `opt -run-twice`, instead of writing tedious
unit tests. That feature has a couple of properties that makes it hard
to use for this purpose though:

1. CloneModule doesn't copy source filename, making `opt -run-twice`
  report it as a difference.
2. `opt -run-twice` does the second run on the original module, not
  its clone, making the result of cloning completely invisible in opt's
  actual output with and without `-run-twice` both, which directly
  contradicts `opt -run-twice`s own error message.

This patch fixes this as well.

Reviewed By: aprantl

Reviewers: loladiro, GorNishanov, espindola, echristo, dexonsmith

Subscribers: vsk, debug-info, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D45593

llvm-svn: 330069
2018-04-13 21:22:24 +00:00
Reid Kleckner 0828699488 [FastISel] Disable local value sinking by default
This is causing compilation timeouts on code with long sequences of
local values and calls (i.e. foo(1); foo(2); foo(3); ...).  It turns out
that code coverage instrumentation is a great way to create sequences
like this, which how our users ran into the issue in practice.

Intel has a tool that detects these kinds of non-linear compile time
issues, and Andy Kaylor reported it as PR37010.

The current sinking code scans the whole basic block once per local
value sink, which happens before emitting each call. In theory, local
values should only be introduced to be used by instructions between the
current flush point and the last flush point, so we should only need to
scan those instructions.

llvm-svn: 329822
2018-04-11 16:03:07 +00:00
Pavel Labath b7243ed2f4 [CodeGen/Dwarf] Rename the "sizetype" synthetic type and add it to the accelerator table
Summary:
This type is created on-demand and used as the base type for array
ranges. Since it is "special", its construction did not go through the
createTypeDIE function and so it was never inserted into the accelerator
table, although it clearly belongs there.

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

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

Reviewers: JDevlieghere, aprantl, dblaikie

Subscribers: llvm-commits

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

llvm-svn: 329705
2018-04-10 14:23:41 +00:00
Pavel Labath 6088c23431 Re-commit r329179 after fixing build&test issues
- MSVC was not OK with a static_assert referencing a non-static member
  variable, even though it was just in a sizeof(expression). I move the
  assert into the emit function, where it is probably more useful.
- Tests were failing in builds which did not have the X86 target
  configured. Since this functionality is not target-specific, I have
  removed the target specifiers from the .ll files.

llvm-svn: 329201
2018-04-04 14:42:14 +00:00