Commit Graph

4251 Commits

Author SHA1 Message Date
Pavel Labath 2f0881160c [DebugInfo] Reduce debug_str_offsets section size
Summary:
The accelerator tables use the debug_str section to store their strings.
However, they do not support the indirect method of access that is
available for the debug_info section (DW_FORM_strx et al.).

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

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

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

Reviewers: probinson, dblaikie, JDevlieghere

Subscribers: aprantl, mgrang, llvm-commits

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

llvm-svn: 339122
2018-08-07 09:54:52 +00:00
Lei Liu 8e422b8403 [AArch64] DWARF: do not generate AT_location for thread local
AArch64 ELF ABI does not define a static relocation type for TLS offset within
a module, which makes it impossible for compiler to generate a valid
DW_AT_location content for thread local variables. Currently LLVM generates an
invalid R_AARCH64_ABS64 relocation at the DW_AT_location field for a TLS
variable. That causes trouble for linker because thread local variable does
not have an absolute address at link time. AArch64 GCC solves the problem by
not generating DW_AT_location for thread local variables. We should do the
same in LLVM.

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

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

Reviewers: probinson, echristo, dblaikie

Subscribers: aprantl, JDevlieghere, llvm-commits

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

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

See PR38190 for more information.

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

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

Reviewers: aprantl, dblaikie, probinson

Reviewed by: dblaikie

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

llvm-svn: 338487
2018-08-01 05:48:06 +00:00
Wolfgang Pieb baf94f830b [DWARF] Do not create a .debug_ranges section when no ranges are needed.
Reviewers: aprantl

Differential Revision: https://reviews.llvm.org/D50089

llvm-svn: 338437
2018-07-31 20:56:32 +00:00
Vlad Tsyrklevich 48ed9acede Revert "[DebugInfo] Generate DWARF debug information for labels."
This reverts commits r338390 and r338398, they were causing LSan
failures on the ASan bot.

llvm-svn: 338408
2018-07-31 18:10:37 +00:00
Hsiangkai Wang cbc58ada99 [DebugInfo] Generate DWARF debug information for labels.
There are two forms for label debug information in DWARF format.

1. Labels in a non-inlined function:

DW_TAG_label
  DW_AT_name
  DW_AT_decl_file
  DW_AT_decl_line
  DW_AT_low_pc

2. Labels in an inlined function:

DW_TAG_label
  DW_AT_abstract_origin
  DW_AT_low_pc

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

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

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

It also generates label debug information under global isel.

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

llvm-svn: 338390
2018-07-31 14:48:32 +00:00
Fangrui Song f78650a8de Remove trailing space
sed -Ei 's/[[:space:]]+$//' include/**/*.{def,h,td} lib/**/*.{cpp,h}

llvm-svn: 338293
2018-07-30 19:41:25 +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
Alexey Bataev 4dd7558fab [DEBUGINFO, NVPTX] Emit correct debug information for local variables.
Summary:
NVPTX target dos not use register-based frame information. Instead it
relies on the artificial local_depot that is used instead of the frame
and the data for variables must be emitted relatively to this
local_depot.

Reviewers: tra, jlebar, echristo

Subscribers: jholewinski, aprantl, JDevlieghere, llvm-commits

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

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

Reviewers: tra, jlebar, echristo

Subscribers: jholewinski, JDevlieghere, llvm-commits

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

llvm-svn: 338036
2018-07-26 16:10:05 +00:00
Pavel Labath 7bfa5d6544 dwarfgen: Add support for generating the debug_str_offsets section, take 3
Previous version of this patch failed on darwin targets because of
different handling of cross-debug-section relocations. This fixes the
tests to emit the DW_AT_str_offsets_base attribute correctly in both
cases. Since doing this is a non-trivial amount of code, and I'm going
to need it in more than one test, I've added a helper function to the
dwarfgen DIE class to do it.

Original commit message follows:

The motivation for this is D49493, where we'd like to test details of
debug_str_offsets behavior which is difficult to trigger from a
traditional test.

This adds the plubming necessary for dwarfgen to generate this section.
The more interesting changes are:
- I've moved emitStringOffsetsTableHeader function from DwarfFile to
  DwarfStringPool, so I can generate the section header more easily from
  the unit test.
- added a new addAttribute overload taking an MCExpr*. This is used to
  generate the DW_AT_str_offsets_base, which links a compile unit to the
  offset table.

I've also added a basic test for reading and writing DW_form_strx forms.

Reviewers: dblaikie, JDevlieghere, probinson

Subscribers: llvm-commits, aprantl

Differential Revision: https://reviews.llvm.org/D49670

llvm-svn: 338031
2018-07-26 14:36:07 +00:00
Martin Storsjo 9dafd6f6d9 Revert "[COFF] Use comdat shared constants for MinGW as well"
This reverts commit r337951.

While that kind of shared constant generally works fine in a MinGW
setting, it broke some cases of inline assembly that worked before:

$ cat const-asm.c
int MULH(int a, int b) {
    int rt, dummy;
    __asm__ (
        "imull %3"
        :"=d"(rt), "=a"(dummy)
        :"a"(a), "rm"(b)
    );
    return rt;
}
int func(int a) {
    return MULH(a, 1);
}
$ clang -target x86_64-win32-gnu -c const-asm.c -O2
const-asm.c:4:9: error: invalid variant '00000001'
        "imull %3"
        ^
<inline asm>:1:15: note: instantiated into assembly here
        imull __real@00000001(%rip)
                     ^

A similar error is produced for i686 as well. The same test with a
target of x86_64-win32-msvc or i686-win32-msvc works fine.

llvm-svn: 338018
2018-07-26 10:48:20 +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 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
Martin Storsjo ff33a95ed4 [COFF] Use comdat shared constants for MinGW as well
GNU binutils tools have no problems with this kind of shared constants,
provided that we actually hook it up completely in AsmPrinter and
produce a global symbol.

This effectively reverts SVN r335918 by hooking the rest of it up
properly.

This feature was implemented originally in SVN r213006, with no reason
for why it can't be used for MinGW other than the fact that GCC doesn't
do it while MSVC does.

Differential Revision: https://reviews.llvm.org/D49646

llvm-svn: 337951
2018-07-25 18:35:42 +00:00
Martin Storsjo d2662c32fb [COFF] Hoist constant pool handling from X86AsmPrinter into AsmPrinter
In SVN r334523, the first half of comdat constant pool handling was
hoisted from X86WindowsTargetObjectFile (which despite the name only
was used for msvc targets) into the arch independent
TargetLoweringObjectFileCOFF, but the other half of the handling was
left behind in X86AsmPrinter::GetCPISymbol.

With only half of the handling in place, inconsistent comdat
sections/symbols are created, causing issues with both GNU binutils
(avoided for X86 in SVN r335918) and with the MS linker, which
would complain like this:

fatal error LNK1143: invalid or corrupt file: no symbol for COMDAT section 0x4

Differential Revision: https://reviews.llvm.org/D49644

llvm-svn: 337950
2018-07-25 18:35:31 +00:00
Pavel Labath da3c4fb5fe Revert "dwarfgen: Add support for generating the debug_str_offsets section, take 2"
This reverts commit r337933. The build error is fixed but the test now
fails on the darwin buildbots. Investigating...

llvm-svn: 337935
2018-07-25 16:34:43 +00:00
Pavel Labath 78ab659bb4 dwarfgen: Add support for generating the debug_str_offsets section, take 2
This recommits r337910 after fixing an "ambiguous call to addAttribute"
error with some compilers (gcc circa 4.9 and MSVC). It seems that these
compilers will consider a "false -> pointer" conversion during overload
resolution. This creates ambiguity because one I added an overload which
takes a MCExpr * as an argument.

I fix this by making the new overload take MCExpr&, which avoids the
conversion. It also documents the fact that we expect a valid MCExpr
object.

Original commit message follows:

The motivation for this is D49493, where we'd like to test details of
debug_str_offsets behavior which is difficult to trigger from a
traditional test.

This adds the plubming necessary for dwarfgen to generate this section.
The more interesting changes are:
- I've moved emitStringOffsetsTableHeader function from DwarfFile to
  DwarfStringPool, so I can generate the section header more easily from
  the unit test.
- added a new addAttribute overload taking an MCExpr*. This is used to
  generate the DW_AT_str_offsets_base, which links a compile unit to the
  offset table.

I've also added a basic test for reading and writing DW_form_strx forms.

Reviewers: dblaikie, JDevlieghere, probinson

Subscribers: llvm-commits, aprantl

Differential Revision: https://reviews.llvm.org/D49670

llvm-svn: 337933
2018-07-25 15:33:32 +00:00
Pavel Labath b4e17c29dd Revert "dwarfgen: Add support for generating the debug_str_offsets section"
This reverts commit r337910 as it's generating "ambiguous call to
addAttribute" errors on some bots.

Will resubmit once I get a chance to look into the problem.

llvm-svn: 337924
2018-07-25 12:52:30 +00:00
Pavel Labath 7a59e3bf37 dwarfgen: Add support for generating the debug_str_offsets section
Summary:
The motivation for this is D49493, where we'd like to test details of
debug_str_offsets behavior which is difficult to trigger from a
traditional test.

This adds the plubming necessary for dwarfgen to generate this section.
The more interesting changes are:
- I've moved emitStringOffsetsTableHeader function from DwarfFile to
  DwarfStringPool, so I can generate the section header more easily from
  the unit test.
- added a new addAttribute overload taking an MCExpr*. This is used to
  generate the DW_AT_str_offsets_base, which links a compile unit to the
  offset table.

I've also added a basic test for reading and writing DW_form_strx forms.

Reviewers: dblaikie, JDevlieghere, probinson

Subscribers: llvm-commits, aprantl

Differential Revision: https://reviews.llvm.org/D49670

llvm-svn: 337910
2018-07-25 11:55:59 +00:00
Shiva Chen f5938bfbf9 Revert "[DebugInfo] Generate DWARF debug information for labels."
This reverts commit b454fa1b4079b6c0a5b1565982d16516385838d7.

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

1. Labels in a non-inlined function:

DW_TAG_label
  DW_AT_name
  DW_AT_decl_file
  DW_AT_decl_line
  DW_AT_low_pc

2. Labels in an inlined function:

DW_TAG_label
  DW_AT_abstract_origin
  DW_AT_low_pc

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

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

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

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

Patch by Hsiangkai Wang.

llvm-svn: 337799
2018-07-24 02:22:55 +00:00
Pavel Labath 0120691f53 Fix build breakage from r337562
I changed a variable's type from pointer to reference, but forgot to
update the assert-only code.

llvm-svn: 337564
2018-07-20 15:40:24 +00:00
Pavel Labath 7f7e60694e DwarfDebug: Reduce duplication in addAccel*** methods
Summary:
Each of the four methods had a dozen lines and was doing almost exactly
the same thing: get the appropriate accelerator table kind and insert an
entry into it. I move this common logic to a helper function and make
these methods delegate to it.

This came up in the context of D49493, where I've needed to make adding
a string to a string pool slightly more complicated, and it seemed to
make sense to do it in one place instead of five.

To make this work I've needed to unify the interface of the AccelTable
data types, as some used to store DIE& and others DIE*. I chose to unify
to a reference as that's what the caller uses.

This technically isn't NFC, because it changes the StringPool used for
apple tables in the DWO case (now it uses the main file like DWARF v5
instead of the DWO file). However, that shouldn't matter, as DWO is not
a thing on apple targets (clang frontend simply ignores -gsplit-dwarf).

Reviewers: JDevlieghere, aprantl, probinson

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D49542

llvm-svn: 337562
2018-07-20 15:24:13 +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
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
Simon Pilgrim 3cb3056fca Fix -Wdocumentation warning. NFCI.
llvm-svn: 337367
2018-07-18 09:07:54 +00:00
Peter Collingbourne fc50498ced CodeGen: Don't create address significance table entries for thread-local variables.
The presence of these symbols in the symbol table can cause symbol type
mismatch errors (or undefined symbol errors on emulated TLS targets)
and they can't be ICF'd anyway.

llvm-svn: 337338
2018-07-18 00:21:40 +00:00
Peter Collingbourne bd9d313d5c CodeGen: Add a target option for emitting .addrsig directives for all address-significant symbols.
Differential Revision: https://reviews.llvm.org/D48143

llvm-svn: 337331
2018-07-17 22:40:08 +00:00
Fangrui Song cb0bab86b3 [CodeGen] Fix inconsistent declaration parameter name
llvm-svn: 337200
2018-07-16 18:51:40 +00:00
Jonas Devlieghere 98062cb396 [AccelTable] Provide DWARF5AccelTableStaticData for dsymutil.
For dsymutil we want to store offsets in the accelerator table entries
rather than DIE pointers. In addition, we need a way to communicate
which CU a DIE belongs to. This patch provides support for both of these
issues.

Differential revision: https://reviews.llvm.org/D49102

llvm-svn: 337158
2018-07-16 10:52:27 +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
Jonas Devlieghere 3192e35b60 Revert "[AccelTable] Provide abstraction for emitting DWARF5 accelerator tables."
This reverts r336529 because an alternative approach turned out to be a
better fit for dsymuil.

llvm-svn: 336698
2018-07-10 16:18:56 +00:00
Wolfgang Pieb e194f73e9f [DWARF][NFC] Refactor range list emission to use a static helper
This is prep for DWARF v5 range list emission. Emission of a single range list is moved
to a static helper function.

Reviewer: jdevlieghere

Differential Revision: https://reviews.llvm.org/D49098

llvm-svn: 336621
2018-07-10 00:10:11 +00:00
Jonas Devlieghere 5e810a878d [AccelTable] Provide abstraction for emitting DWARF5 accelerator tables.
When emitting the DWARF accelerator tables from dsymutil, we don't have
a DwarfDebug instance and we use a custom class to represent Dwarf
compile units. This patch adds an interface AccelTableWriterInfo to
abstract these from the Dwarf5AccelTableWriter, so we can have a custom
implementation for this in dsymutil.

Differential revision: https://reviews.llvm.org/D49031

llvm-svn: 336529
2018-07-09 09:08:44 +00:00
Jonas Devlieghere e60ca777b6 [AccelTable] Dwarf5AccelTableEmitter -> Writer (NFC)
Renames Dwarf5AccelTableEmitter to Dwarf5AccelTableWriter as suggested
in D49031.

llvm-svn: 336525
2018-07-09 08:47:38 +00:00
Vedant Kumar 6379a62250 [Local] replaceAllDbgUsesWith: Update debug values before RAUW
The replaceAllDbgUsesWith utility helps passes preserve debug info when
replacing one value with another.

This improves upon the existing insertReplacementDbgValues API by:

- Updating debug intrinsics in-place, while preventing use-before-def of
  the replacement value.
- Falling back to salvageDebugInfo when a replacement can't be made.
- Moving the responsibiliy for rewriting llvm.dbg.* DIExpressions into
  common utility code.

Along with the API change, this teaches replaceAllDbgUsesWith how to
create DIExpressions for three basic integer and pointer conversions:

- The no-op conversion. Applies when the values have the same width, or
  have bit-for-bit compatible pointer representations.
- Truncation. Applies when the new value is wider than the old one.
- Zero/sign extension. Applies when the new value is narrower than the
  old one.

Testing:

- check-llvm, check-clang, a stage2 `-g -O3` build of clang,
  regression/unit testing.
- This resolves a number of mis-sized dbg.value diagnostics from
  Debugify.

Differential Revision: https://reviews.llvm.org/D48676

llvm-svn: 336451
2018-07-06 17:32:39 +00:00
Alexey Bataev 2a03d4296a [DEBUG_INFO, NVPTX] Do not emit .debug_loc section.
Summary:
.debug_loc section is not supported for NVPTX target. If there is an
object whose location can change during its lifetime, we do not generate
debug location info for this variable.

Reviewers: echristo

Subscribers: jholewinski, JDevlieghere, llvm-commits

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

llvm-svn: 335976
2018-06-29 14:23:28 +00:00
Petar Jovanovic d175aeb881 [DwarfDebug] Remove unused argument (NFC)
Remove unused ByteStreamer argument from function emitDebugLocValue.

Patch by Nikola Prica.

Differential Revision: https://reviews.llvm.org/D48590

llvm-svn: 335811
2018-06-28 04:50:40 +00:00
George Rimar dcf59c5480 Recommit r335333 "[MC] - Add .stack_size sections into groups and link them with .text"
With compilation fix.

Original commit message:

D39788 added a '.stack-size' section containing metadata on function stack sizes
to output ELF files behind the new -stack-size-section flag.

This change does following two things on top:

1) Imagine the case when there are -ffunction-sections flag given and there are text sections in COMDATs. 
    The patch adds a '.stack-size' section into corresponding COMDAT group, so that linker will be able to
    eliminate them fast during resolving the COMDATs.
2) Patch sets a SHF_LINK_ORDER flag and links '.stack-size' with the corresponding .text.
   With that linker will be able to do -gc-sections on dead stack sizes sections.

Differential revision: https://reviews.llvm.org/D46874

llvm-svn: 335336
2018-06-22 10:53:47 +00:00
George Rimar 6d448da1be Revert r335332 "[MC] - Add .stack_size sections into groups and link them with .text"
It broke bots.

http://lab.llvm.org:8011/builders/clang-ppc64le-linux-lnt/builds/12891
http://lab.llvm.org:8011/builders/clang-cmake-x86_64-sde-avx512-linux/builds/9443
http://lab.llvm.org:8011/builders/lldb-x86_64-ubuntu-14.04-buildserver/builds/25551

llvm-svn: 335333
2018-06-22 10:27:33 +00:00
George Rimar e14485a0c6 [MC] - Add .stack_size sections into groups and link them with .text
D39788 added a '.stack-size' section containing metadata on function stack sizes
to output ELF files behind the new -stack-size-section flag.

This change does following two things on top:

1) Imagine the case when there are -ffunction-sections flag given and there are text sections in COMDATs. 
    The patch adds a '.stack-size' section into corresponding COMDAT group, so that linker will be able to
    eliminate them fast during resolving the COMDATs.
2) Patch sets a SHF_LINK_ORDER flag and links '.stack-size' with the corresponding .text.
   With that linker will be able to do -gc-sections on dead stack sizes sections.

Differential revision: https://reviews.llvm.org/D46874

llvm-svn: 335332
2018-06-22 10:10:53 +00:00
Brock Wyma b60532f89a [CodeView] Omit forward references for unnamed structs and unions
Codeview references to unnamed structs and unions are expected to refer to the
complete type definition instead of a forward reference so Visual Studio can
resolve the type properly.

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

llvm-svn: 334382
2018-06-11 01:39:34 +00:00
Vedant Kumar 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
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
Eric Christopher 68f2218e1e Revert "Temporarily revert "[DEBUG] Initial adaptation of NVPTX target for debug info emission.""
This reapplies commits: r330271, r330592, r330779.

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

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

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

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

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

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

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

llvm-svn: 332669
2018-05-17 21:22:48 +00:00
Brock Wyma 3db2b108c3 [CodeView] Improve debugging of virtual base class member variables
Initial support for passing the virtual base pointer offset to CodeViewDebug.

https://reviews.llvm.org/D46271

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

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

Reviewers: probinson, aprantl, JDevlieghere

Subscribers: llvm-commits

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

llvm-svn: 332246
2018-05-14 14:13:20 +00:00
Nicola Zaghen d34e60ca85 Rename DEBUG macro to LLVM_DEBUG.
The DEBUG() macro is very generic so it might clash with other projects.
The renaming was done as follows:
- git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g'
- git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM
- Manual change to APInt
- Manually chage DOCS as regex doesn't match it.

In the transition period the DEBUG() macro is still present and aliased
to the LLVM_DEBUG() one.

Differential Revision: https://reviews.llvm.org/D43624

llvm-svn: 332240
2018-05-14 12:53:11 +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 801bf7ebbe [DebugInfo] Examine all uses of isDebugValue() for debug instructions.
Because we create a new kind of debug instruction, DBG_LABEL, we need to
check all passes which use isDebugValue() to check MachineInstr is debug
instruction or not. When expelling debug instructions, we should expel
both DBG_VALUE and DBG_LABEL. So, I create a new function,
isDebugInstr(), in MachineInstr to check whether the MachineInstr is
debug instruction or not.

This patch has no new test case. I have run regression test and there is
no difference in regression test.

Differential Revision: https://reviews.llvm.org/D45342

Patch by Hsiangkai Wang.

llvm-svn: 331844
2018-05-09 02:42:00 +00:00
Shiva Chen cd070cdc94 [DebugInfo] Convert intrinsic llvm.dbg.label to MachineInstr.
In order to convert LLVM IR to MachineInstr, we need a new TargetOpcode,
DBG_LABEL, to ‘lower’ intrinsic llvm.dbg.label. The patch
creates this new TargetOpcode and convert intrinsic llvm.dbg.label to
MachineInstr through SelectionDAG.

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

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

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

Patch by Hsiangkai Wang.

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

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

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

llvm.dbg.label(metadata !1)

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

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

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

Patch by Hsiangkai Wang.

llvm-svn: 331841
2018-05-09 02:40:45 +00:00
Martin Storsjo 966d34563f [AsmPrinter] Allow emitting codeview for any windows target
Before SVN r244158, codeview debug info was emitted always
emitted for msvc if debug info was enabled, but that commit
added a module flag.

Since it's still restricted by the flag, we can allow it
for any target if the user requests it, not only msvc (and
windows-itanium, added in SVN r287567).

Add a test for emitting it for a mingw target.

Differential Revision: https://reviews.llvm.org/D46303

llvm-svn: 331809
2018-05-08 20:56:04 +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
Krzysztof Parzyszek 5e3aba8251 Add assertion to padding size calculation, NFC
The size of an object cannot be less than the emitted size of all the
contained elements. This would cause an overflow in padding size
calculation. Add an assert to catch this.

Patch by Suyog Sarda.

llvm-svn: 331376
2018-05-02 17:20:22 +00:00
Adrian Prantl 5f8f34e459 Remove \brief commands from doxygen comments.
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.

Patch produced by

  for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done

Differential Revision: https://reviews.llvm.org/D46290

llvm-svn: 331272
2018-05-01 15:54:18 +00:00
Eric Christopher 8024425801 Temporarily revert "[DEBUG] Initial adaptation of NVPTX target for debug info emission."
This appears to have some issues associated with the file directive output
causing multiple global symbols with the name "file" to be emitted into a
startup section. I'm investigating more specific causes and working with the
original author.

This reverts commit r330271.

Also Revert "[DEBUGINFO, NVPTX] Add the test for the debug info of the local"

This reverts commit r330592 and the follow up of 330779 as the testcase is dependent upon r330271.

llvm-svn: 331237
2018-05-01 00:10:13 +00:00
Nirav Dave 6c0665e221 [MC] Change AsmParser to leverage Assembler during evaluation
Teach AsmParser to check with Assembler for when evaluating constant
expressions.  This improves the handing of preprocessor expressions
that must be resolved at parse time. This idiom can be found as
assembling-time assertion checks in source-level assemblers. Note that
this relies on the MCStreamer to keep sufficient tabs on Section /
Fragment information which the MCAsmStreamer does not. As a result the
textual output may fail where the equivalent object generation would
pass. This can most easily be resolved by folding the MCAsmStreamer
and MCObjectStreamer together which is planned for in a separate
patch.

Currently, this feature is only enabled for assembly input, keeping IR
compilation consistent between assembly and object generation.

Reviewers: echristo, rnk, probinson, espindola, peter.smith

Reviewed By: peter.smith

Subscribers: eraman, peter.smith, arichardson, jyknight, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D45164

llvm-svn: 331218
2018-04-30 19:22:40 +00:00
Nico Weber 432a38838d IWYU for llvm-config.h in llvm, additions.
See r331124 for how I made a list of files missing the include.
I then ran this Python script:

    for f in open('filelist.txt'):
        f = f.strip()
        fl = open(f).readlines()

        found = False
        for i in xrange(len(fl)):
            p = '#include "llvm/'
            if not fl[i].startswith(p):
                continue
            if fl[i][len(p):] > 'Config':
                fl.insert(i, '#include "llvm/Config/llvm-config.h"\n')
                found = True
                break
        if not found:
            print 'not found', f
        else:
            open(f, 'w').write(''.join(fl))

and then looked through everything with `svn diff | diffstat -l | xargs -n 1000 gvim -p`
and tried to fix include ordering and whatnot.

No intended behavior change.

llvm-svn: 331184
2018-04-30 14:59:11 +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
Nirav Dave 6b01b88012 [MC] Undo spurious commit added into r331052.
llvm-svn: 331055
2018-04-27 16:16:06 +00:00
Nirav Dave 38b4b54a2c [MC] Provide default value for IsResolved.
llvm-svn: 331052
2018-04-27 16:11:24 +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
Eric Christopher aadbabc070 Remove unused argument from emitModuleMetadata.
NFCI.

llvm-svn: 330470
2018-04-20 19:07:57 +00:00
Alexey Bataev 242706b8d1 [DEBUG] Initial adaptation of NVPTX target for debug info emission.
Summary:
Patch adds initial emission of the debug info for NVPTX target.
Currently, only .file and .loc directives are emitted, everything else is
commented out to not break the compilation of Cuda.

Reviewers: echristo, jlebar, tra, jholewinski

Subscribers: mgorny, aprantl, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D41827

llvm-svn: 330271
2018-04-18 16:13:41 +00:00
Pavel Labath 3fb39c79ed [CodeGen/Dwarf] Make debug_names compatible with split-dwarf
Summary:
Previously we crashed for the combination of the two features because we
tried to reference the dwo CU from the main object file. The fix
consists of two items:
- reference the skeleton CU from the name index (the consumer is
  expected to use the skeleton CU to find the real data).
- use the main object file string pool for the strings in the index

Reviewers: JDevlieghere, aprantl, dblaikie

Subscribers: llvm-commits

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

llvm-svn: 330249
2018-04-18 12:11:59 +00:00
Brock Wyma 94ece8fbc9 [CodeView] Initial support for emitting S_THUNK32 symbols for compiler...
When emitting CodeView debug information, compiler-generated thunk routines
should be emitted using S_THUNK32 symbols instead of S_GPROC32_ID symbols so
Visual Studio can properly step into the user code.  This initial support only
handles standard thunk ordinals.

Differential Revision: https://reviews.llvm.org/D43838

llvm-svn: 330132
2018-04-16 16:53:57 +00:00
Peter Collingbourne cb8a666f4b CodeGen: Don't try to canonicalize Unix-style paths in CodeView debug info.
Most importantly, we should not replace slashes with backslashes
because that would invalidate the path.

Differential Revision: https://reviews.llvm.org/D45473

llvm-svn: 329838
2018-04-11 18:24:03 +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
Alexandre Ganea d9e96741c4 [Debuginfo][COFF] Minimal serialization support for precompiled types records
This change adds support for the LF_PRECOMP and LF_ENDPRECOMP records required
to read/write Microsoft precompiled types .objs.
See https://en.wikipedia.org/wiki/Precompiled_header#Microsoft_Visual_C_and_C++

This also adds handling for the .debug$P section, which is actually a .debug$T
section in disguise, found only in precompiled .objs.

Differential Revision: https://reviews.llvm.org/D45283

llvm-svn: 329613
2018-04-09 20:17:56 +00:00
Pavel Labath eadfac8748 [CodeGen/AccelTable] Don't emit zero-CU name indexes
Summary:
If an input DICompileUnit is completely empty (e.g., the result of
running "clang -g" on an empty file), we don't bother emitting an empty
DWARF CU. When we do that, we must make sure we don't also emit a DWARF v5
name index, as DWARF specifies that each index must reference at least
one compilation unit.

Reviewers: JDevlieghere, aprantl, dblaikie

Subscribers: llvm-commits

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

llvm-svn: 329575
2018-04-09 14:38:53 +00:00
Pavel Labath 889bf9fe00 [CodeGen/AccelTable]: Don't emit accelerator entries for functions with no names
Summary:
We were emitting accelerator entries for functions with no name, which
is contrary to the DWARF v5 spec: "All other (i.e., *not*
DW_TAG_namespace) debugging information entries without a DW_AT_name
attribute are excluded." Besides that, a name table entry with an empty
string as a key is fairly useless.

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

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

Reviewers: JDevlieghere, aprantl, dblaikie

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

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

llvm-svn: 329552
2018-04-09 08:41:57 +00:00
Michael Zolotukhin 8d052a0dd2 Remove MachineLoopInfo dependency from AsmPrinter.
Summary:
Currently MachineLoopInfo is used in only two places:
1) for computing IsBasicBlockInsideInnermostLoop field of MCCodePaddingContext, and it is never used.
2) in emitBasicBlockLoopComments, which is called only if `isVerbose()` is true.
Despite that, we currently have a dependency on MachineLoopInfo, which makes
pass manager to compute it and MachineDominator Tree. This patch removes the
use (1) and makes the use (2) lazy, thus avoiding some redundant
recomputations.

Reviewers: opaparo, gadi.haber, rafael, craig.topper, zvi

Subscribers: rengolin, javed.absar, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D44812

llvm-svn: 329542
2018-04-09 00:54:47 +00:00
Mandeep Singh Grang e92f0cfe34 [CodeGen] Change std::sort to llvm::sort in response to r327219
Summary:
r327219 added wrappers to std::sort which randomly shuffle the container before sorting.
This will help in uncovering non-determinism caused due to undefined sorting
order of objects having the same key.

To make use of that infrastructure we need to invoke llvm::sort instead of std::sort.

Note: This patch is one of a series of patches to replace *all* std::sort to llvm::sort.
Refer the comments section in D44363 for a list of all the required patches.

Reviewers: bogner, rnk, MatzeB, RKSimon

Reviewed By: rnk

Subscribers: JDevlieghere, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D45133

llvm-svn: 329435
2018-04-06 18:08:42 +00:00
Pavel Labath 0cc0306a75 Fix build breakage from r329201
Some compilers do not like having an enum type and a variable with the
same name (AccelTableKind). I rename the variable to TheAccelTableKind.

Suggestions for a better name welcome.

llvm-svn: 329202
2018-04-04 14:54:08 +00:00
Pavel Labath 6088c23431 Re-commit r329179 after fixing build&test issues
- MSVC was not OK with a static_assert referencing a non-static member
  variable, even though it was just in a sizeof(expression). I move the
  assert into the emit function, where it is probably more useful.
- Tests were failing in builds which did not have the X86 target
  configured. Since this functionality is not target-specific, I have
  removed the target specifiers from the .ll files.

llvm-svn: 329201
2018-04-04 14:42:14 +00:00
Nico Weber 55fcd07d25 Revert r329179 (and follow-up unsuccessful fix attempts 329184, 329186); it doesn't build.
llvm-svn: 329190
2018-04-04 13:06:22 +00:00
Nico Weber be6a9b6d7d Attempt to fix bots more after r329179.
llvm-svn: 329186
2018-04-04 12:58:49 +00:00
Nico Weber 7e654e3231 Attempt to fix bots after r329179.
llvm-svn: 329184
2018-04-04 12:54:34 +00:00
Pavel Labath 69baab103a [CodeGen] Generate DWARF v5 Accelerator Tables
Summary:
This patch adds a DwarfAccelTableEmitter class, which generates an
accelerator table, as specified in DWARF v5 standard. At the moment it
only generates a DIE offset column and (if we are indexing more than one
compile unit) a CU column.

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

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

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

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

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

llvm-svn: 329179
2018-04-04 12:28:20 +00:00
Rafael Espindola 8c58750cc4 Align stubs for external and common global variables to pointer size.
This patch fixes PR36885: clang++ generates unaligned stub symbol
holding a pointer.

Patch by Rahul Chaudhry!

llvm-svn: 329030
2018-04-02 23:20:30 +00:00
Jonas Devlieghere 9e3e7a99e8 [dsymutil] Upstream emitting of papertrail warnings.
When running dsymutil as part of your build system, it can be desirable
for warnings to be part of the end product, rather than just being
emitted to the output stream. This patch upstreams that functionality.

Differential revision: https://reviews.llvm.org/D44639

llvm-svn: 328965
2018-04-02 10:40:43 +00:00
Rafael Espindola 4b4d85fd4d Style update. NFC.
Rename 3 functions to start with lowercase letters. Don't repeat the
name in the comments.

llvm-svn: 328848
2018-03-29 23:32:54 +00:00
Paul Robinson b271f31d8d Reapply "[DWARFv5] Emit file 0 to the line table."
DWARF v5 specifies that the root file (also given in the DW_AT_name
attribute of the compilation unit DIE) should be emitted explicitly to
the line table's list of files.  This makes the line table more
independent of the .debug_info section.
We emit the new syntax only for DWARF v5 and later.

Fixes the bug found by asan. Also XFAIL the new test for Darwin, which
is stuck on DWARF v2, and fix up other tests so they stop failing on
Windows.  Last but not least, don't break "clang -g" of an assembler
file that has .file directives in it.

Differential Revision: https://reviews.llvm.org/D44054

llvm-svn: 328805
2018-03-29 17:16:41 +00:00
Alexander Potapenko 202f809437 Revert "Reapply "[DWARFv5] Emit file 0 to the line table.""
This reverts commit r328676.

Commit r328676 broke the -no-integrated-as flag necessary to build Linux kernel with Clang:

$ cat t.c
void foo() {}
$ clang -no-integrated-as   -c  t.c -g
/tmp/t-dcdec5.s: Assembler messages:
/tmp/t-dcdec5.s:8: Error: file number less than one
clang-7.0: error: assembler command failed with exit code 1 (use -v to see invocation)

llvm-svn: 328699
2018-03-28 12:36:46 +00:00
Paul Robinson 07480bd177 Reapply "[DWARFv5] Emit file 0 to the line table."
DWARF v5 specifies that the root file (also given in the DW_AT_name
attribute of the compilation unit DIE) should be emitted explicitly to
the line table's list of files.  This makes the line table more
independent of the .debug_info section.

Fixes the bug found by asan. Also XFAIL the new test for Darwin, which
is stuck on DWARF v2, and fix up other tests so they stop failing on
Windows.  Last but not least, don't break "clang -g" of an assembler
file that has .file directives in it.

Differential Revision: https://reviews.llvm.org/D44054

llvm-svn: 328676
2018-03-27 22:40:34 +00:00
Paul Robinson 7cb26ad2ef [DWARF] Suppress split line tables more carefully.
If a given split type unit does not have source locations, don't have
it refer to the split line table.
If no split type unit refers to the split line table, don't emit the
line table at all.

This will save a little space on rare occasions, but also refactors
things a bit to improve which class is responsible for what.

Responding to review comments on r326395.

Differential Revision: https://reviews.llvm.org/D44220

llvm-svn: 328670
2018-03-27 21:28:59 +00:00
Rafael Espindola 78fdca3cd5 Use local symbols for creating .stack-size.
llvm-svn: 328581
2018-03-26 20:40:22 +00:00
David Blaikie 6054e650ff Move TargetLoweringObjectFile from CodeGen to Target to fix layering
It's implemented in Target & include from other Target headers, so the
header should be in Target.

llvm-svn: 328392
2018-03-23 23:58:19 +00:00
Alexey Bataev bff360865b [DEBUGINFO] Add flag for DWARF2 to use sections as references.
Summary:
Some targets does not support labels inside debug sections, but support
references in form `section+offset`. Patch adds initial support
for this.

Reviewers: echristo, probinson, jlebar

Subscribers: llvm-commits, JDevlieghere

Differential Revision: https://reviews.llvm.org/D43943

llvm-svn: 328314
2018-03-23 13:35:54 +00:00
Alexey Bataev 07254641d3 [DWARF] Add EmitDwarfOffset function, NFC.
Added EmitDwarfOffset function after discussion with Eric Christofer.

llvm-svn: 328212
2018-03-22 16:43:21 +00:00
David Blaikie 8820929011 Sink Analysis/ObjectUtil(canBeOmittedFromSymbolTable) into IR so it can be legitimately be used by Object/IRSymtab
llvm-svn: 328135
2018-03-21 19:23:45 +00:00
Alexey Bataev 858a7dd6d7 [DEBUGINFO] Add -no-dwarf-debug-ranges option.
Summary:
Added option -no-dwarf-debug-ranges option to disable emission of
.debug_ranges section.

Reviewers: probinson, echristo

Subscribers: aprantl, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D44384

llvm-svn: 328030
2018-03-20 20:21:38 +00:00
Alexey Bataev 648ed2dedb [DEBUGINFO] Add flag -no-dwarf-pub-sections to disable pub sections.
Summary:
Added a flag -no-dwarf-pub-sections, which allows to disable
emission of DWARF public sections.

Reviewers: probinson, echristo

Subscribers: aprantl, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D44385

llvm-svn: 327994
2018-03-20 16:04:40 +00:00
Jonas Devlieghere a6ef1abc09 [dsymutil] Rename llvm-dsymutil -> dsymutil
Now that almost all functionality of Apple's dsymutil has been
upstreamed, the open source variant can be used as a drop in
replacement. Hence we feel it's no longer necessary to have the llvm
prefix.

Differential revision: https://reviews.llvm.org/D44527

llvm-svn: 327790
2018-03-18 11:38:41 +00:00
Reid Kleckner 5a791ee408 Re-land r327620 "[CodeView] Initial support for emitting S_BLOCK32 symbols for lexical scopes"
This is safe to land now that we don't copy FunctionInfo when rehashing
the DenseMap.

llvm-svn: 327670
2018-03-15 21:24:04 +00:00
Reid Kleckner e9dc30d2c2 [codeview] Fix sense of the assertion about hashtable insertion
llvm-svn: 327669
2018-03-15 21:18:42 +00:00
Reid Kleckner 55baeefd54 [codeview] Delete FunctionInfo copy ctor and move out of DenseMap
We were unnecessarily copying a bunch of these FunctionInfo objects
around when rehashing the DenseMap.

Furthermore, r327620 introduced pointers referring to objects owned by
FunctionInfo, and the default copy ctor did the wrong thing in this
case, leading to use-after-free when the DenseMap gets rehashed.

I will rebase r327620 on this next and recommit it.

llvm-svn: 327665
2018-03-15 21:12:21 +00:00
Reid Kleckner 7ac8e50e7e Revert r327620 "[CodeView] Initial support for emitting S_BLOCK32 symbols for lexical scopes"
It is causing crashes when compiling Chrome in debug mode.

I'll try to debug it in a second.

llvm-svn: 327657
2018-03-15 20:12:16 +00:00
Brock Wyma 3cc5710cec [CodeView] Initial support for emitting S_BLOCK32 symbols for lexical scopes
This patch sorts local variables by lexical scope and emits them inside
an appropriate S_BLOCK32 CodeView symbol.

Differential Revision: https://reviews.llvm.org/D42926

llvm-svn: 327620
2018-03-15 11:52:17 +00:00
Pavel Labath 8ed6582bb0 Fix msvc compiler error in r327498
msvc reports an "illegal indirection" error here. Attempt to appease it
with a different initialization syntax.

llvm-svn: 327500
2018-03-14 11:31:17 +00:00
Pavel Labath 0dd81bab92 Explicitly initialize dwarf::FormParams in DIEInteger::SizeOf
This could end up inititialized if someone called the function with a
null AsmPrinter. Right now this only happens in DIEHash unit tests,
presumably because it was hard to create an AsmPrinter in the context of
unit tests. This only worked before r327486 because those tests did not
use any dwarf forms whose size actually depended on the dwarf version
(otherwise, they would have crashed due to null dereference).

I fix the uninitialized error, by explicitly initializing FormParams to
an invalid value, which will cause getFixedFormByteSize to return None
if called with a form with version-dependent size. A more principled
solution might be to fix the DIEHash tests to always pass in a valid
AsmPrinter.

llvm-svn: 327498
2018-03-14 11:14:43 +00:00
Pavel Labath 322711f529 DWARF: Unify form size handling code
Summary:
This patch replaces the two switches which are deducing the size of
various forms with a single implementation. I have put the new
implementation into BinaryFormat, to avoid introducing dependencies
between the two independent libraries (DebugInfo and CodeGen) that need
this functionality.

Reviewers: aprantl, JDevlieghere, dblaikie

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D44418

llvm-svn: 327486
2018-03-14 09:39:54 +00:00
Matt Arsenault 41e5ac4fa4 TargetMachine: Add address space to getPointerSize
llvm-svn: 327467
2018-03-14 00:36:23 +00:00
Brock Wyma f52e192293 Revert r327397 [CodeView] Omit forward references for unnamed structs and ...
This reverts commit r327397 to investigate a buildbot failure.

llvm-svn: 327414
2018-03-13 15:56:20 +00:00
Brock Wyma 4fb9184558 [CodeView] Omit forward references for unnamed structs and unions
Codeview references to unnamed structs and unions are expected to refer to the
complete type definition instead of a forward reference so Visual Studio can
resolve the type properly.

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

llvm-svn: 327397
2018-03-13 14:14:16 +00:00
Bjorn Pettersson a223f815dd [SelectionDAG] Improve handling of dangling debug info
Summary:
1) Make sure to discard dangling debug info if the variable (or
variable fragment) is mapped to something new before we had a
chance to resolve the dangling debug info.

2) When resolving debug info, make sure to bump the associated
SDNodeOrder to ensure that the DBG_VALUE is emitted after the
instruction that defines the value used in the DBG_VALUE.
This will avoid a debug-use before def scenario as seen in
https://bugs.llvm.org/show_bug.cgi?id=36417.

The new test case, test/DebugInfo/X86/sdag-dangling-dbgvalue.ll,
show some other limitations in how dangling debug info is
handled in the SelectionDAG. Since we currently only support
having one dangling dbg.value per Value, we will end up dropping
debug info when there are more than one variable that is described
by the same "dangling value".

Reviewers: aprantl

Reviewed By: aprantl

Subscribers: aprantl, eraman, llvm-commits, JDevlieghere

Tags: #debug-info

Differential Revision: https://reviews.llvm.org/D44369

llvm-svn: 327303
2018-03-12 18:02:39 +00:00
Alina Sbirlea 08fa594298 Avoid creating a Constant for each value in a ConstantDataSequential.
Summary: We create a ConstantDataSequential (ConstantDataArray or ConstantDataVector) to avoid creating a Constant for each element in an array of constants. But them in AsmPrinter, we do create a ConstantFP for each element in the ConstantDataSequential. This triggers excessive memory use when generating large global FP constants.

Reviewers: bogner, lhames, t.p.northover

Subscribers: jlebar, sanjoy, llvm-commits

Differential Revision: https://reviews.llvm.org/D44277

llvm-svn: 327161
2018-03-09 18:48:20 +00:00
Matt Davis 4c77cb7d12 [DebugInfo] Add DW_AT_byte_size to vectors
Summary:
This patch adds the DW_AT_byte_size dwarf attribute to vectors.
This fixes PR21924

LLVM will round a vector up to the next alignable address, which can result in
the vector's representation in the object file being larger than what the
debugger will calculate via NumberOfElements * ElementSize. In such a case calling sizeof(MyVec) in the source will result in a different value than what a debugger might present. This situation can occur because LLVM permits non-power of two 'vector_size' attributes.

Reviewers: echristo, dexonsmith, aprantl

Reviewed By: aprantl

Subscribers: probinson, aprantl, llvm-commits, JDevlieghere

Tags: #debug-info

Differential Revision: https://reviews.llvm.org/D44048

llvm-svn: 327072
2018-03-08 22:22:26 +00:00
Alexander Kornienko e12a48bcc0 Revert "Reapply "[DWARFv5] Emit file 0 to the line table.""
This reverts commit r326839.

r326839 breaks assembly file parsing:

$ cat q.c
void g() {}
$ clang -S q.c -g
$ clang -g -c q.s
q.s:9:2: error: file number already allocated
     .file   1 "/tmp/test" "q.c"
     ^

llvm-svn: 326902
2018-03-07 16:27:44 +00:00
Paul Robinson 4428e90efa Reapply "[DWARFv5] Emit file 0 to the line table."
Fixes the bug found by asan. Also XFAIL the new test for Darwin,
which is stuck on DWARF v2, and fix up other tests so they stop
failing on Windows.

llvm-svn: 326839
2018-03-06 22:37:45 +00:00
Aaron Smith 122d9e79ae [CodeView] Emit UdtSourceLine information for enums
Summary:
- Emit UdtSourceLine information for enums to match MSVC

- Add a method to add UDTSrcLine and call it for all Class/Struct/Union/Enum

- Update test cases to verify the changes

Reviewers: zturner, llvm-commits, rnk

Reviewed By: rnk

Differential Revision: https://reviews.llvm.org/D44116

llvm-svn: 326824
2018-03-06 18:20:22 +00:00
Simi Pallipurath ad96d9a373 test commit: fix typo in comment
This is  a simple change to do the test commit and verify commit access.

llvm-svn: 326800
2018-03-06 14:35:23 +00:00
Paul Robinson 732e443bb9 Revert "[DWARFv5] Emit file 0 to the line table."
Caused an asan failure.

This reverts commit d54883f081186cdcce74e6f98cfc0438579ec019.
aka r326758

llvm-svn: 326762
2018-03-06 03:15:21 +00:00
Paul Robinson d5069ba3da [DWARFv5] Emit file 0 to the line table.
DWARF v5 specifies that the root file (also given in the DW_AT_name
attribute of the compilation unit DIE) should be emitted explicitly to
the line table's list of files.  This makes the line table more
independent of the .debug_info section.

Differential Revision: https://reviews.llvm.org/D44054

llvm-svn: 326758
2018-03-06 01:59:56 +00:00
Alexey Bataev d7c6fdbcd5 Revert "[DEBUGINFO] Add flag for DWARF2 or less to use sections as references."
This reverts commit r326328 to remove checks for emission of certain
sections after discussion with Eric Christofer.

llvm-svn: 326436
2018-03-01 14:32:37 +00:00
Paul Robinson 1e0116c91d [DWARF] Emit a split line table only if there are split type units.
A .debug_info.dwo section doesn't use the .debug_line.dwo section.

llvm-svn: 326395
2018-03-01 00:12:35 +00:00
Chih-Hung Hsieh 9f9e4681ac [TLS] use emulated TLS if the target supports only this mode
Emulated TLS is enabled by llc flag -emulated-tls,
which is passed by clang driver.
When llc is called explicitly or from other drivers like LTO,
missing -emulated-tls flag would generate wrong TLS code for targets
that supports only this mode.
Now use useEmulatedTLS() instead of Options.EmulatedTLS to decide whether
emulated TLS code should be generated.
Unit tests are modified to run with and without the -emulated-tls flag.

Differential Revision: https://reviews.llvm.org/D42999

llvm-svn: 326341
2018-02-28 17:48:55 +00:00
Alexey Bataev 9de940b93b [DEBUGINFO] Add flag for DWARF2 or less to use sections as references.
Summary:
Some targets does not support labels inside debug sections, but support
references in form `section +|- offset`. Patch adds initial support
for this. Also, this patch disables emission of all additional debug
  sections that may have labels inside of it (like pub sections and
  string tables).

Reviewers: probinson, echristo

Subscribers: JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D43627

llvm-svn: 326328
2018-02-28 15:02:59 +00:00
Reid Kleckner 3acdc67734 [CodeView] Lower __restrict and other pointer qualifiers correctly
Qualifiers on a pointer or reference type may apply to either the
pointee or the pointer itself. Consider 'const char *' and 'char *
const'. In the first example, the pointee data may not be modified
without casts, and in the second example, the pointer may not be updated
to point to new data.

In the general case, qualifiers are applied to types with LF_MODIFIER
records, which support the usual const and volatile qualifiers as well
as the __unaligned extension qualifier.

However, LF_POINTER records, which are used for pointers, references,
and member pointers, have flags for qualifiers applying to the
*pointer*. In fact, this is the only way to represent the restrict
qualifier, which can only apply to pointers, and cannot qualify regular
data types.

This patch causes LLVM to correctly fold 'const' and 'volatile' pointer
qualifiers into the pointer record, as well as adding support for
'__restrict' qualifiers in the same place.

Based on a patch from Aaron Smith

Differential Revision: https://reviews.llvm.org/D43060

llvm-svn: 326260
2018-02-27 22:08:15 +00:00
Shoaib Meenai 03303a3bb6 [AsmPrinter] Handle qualified unnamed types in CodeView printer
When attempting to compile the following Objective-C++ code with
CodeView debug info:

  void (^b)(void) = []() {};

The generated debug metadata contains a structure like the following:

  !43 = !DICompositeType(tag: DW_TAG_structure_type, name: "__block_literal_1", scope: !6, file: !6, line: 1, size: 168, elements: !44)
  !44 = !{!45, !46, !47, !48, !49, !52}
  ...
  !52 = !DIDerivedType(tag: DW_TAG_member, scope: !6, file: !6, line: 1, baseType: !53, size: 8, offset: 160, flags: DIFlagPublic)
  !53 = !DIDerivedType(tag: DW_TAG_const_type, baseType: !54)
  !54 = !DICompositeType(tag: DW_TAG_class_type, file: !6, line: 1, flags: DIFlagFwdDecl)

Note that the member node (!52) is unnamed, but rather than pointing to
a DICompositeType directly, it points to a DIDerivedType with tag
DW_TAG_const_type, which then points to the DICompositeType. However,
the CodeView assembly printer currently assumes that the base type for
an unnamed member will always be a DICompositeType, and attempts to
perform that cast, which triggers an assertion failure, since in this
case the base type is actually a DIDerivedType, not a DICompositeType
(and we would have to get the base type of the DIDerivedType to reach
the DICompositeType). I think the debug metadata being generated by the
frontend is correct (or at least plausible), and the CodeView printer
needs to handle this case.

This patch teaches the CodeView printer to unwrap any qualifier types.
The qualifiers are just dropped for now. Ideally, they would be applied
to the added indirect members instead, but this occurs infrequently
enough that adding the logic to handle the qualifiers correctly isn't
worth it for now. A FIXME is added to note this.

Additionally, Reid pointed out that the underlying assumption that an
unnamed member must be a composite type is itself incorrect and may not
hold for all frontends. Therefore, after all qualifiers have been
stripped, check if the resulting type is in fact a DICompositeType and
just return if it isn't, rather than assuming the type and crashing if
that assumption is violated.

Differential Revision: https://reviews.llvm.org/D43803

llvm-svn: 326255
2018-02-27 21:48:41 +00:00
Mandeep Singh Grang 46d02dee65 [DebugInfo] Stable sort symbols to remove non-deterministic ordering
Summary: This fixes failure in DebugInfo/X86/multiple-aranges.ll uncovered by D39245.

Reviewers: rafael, echristo, probinson

Reviewed By: probinson

Subscribers: probinson, llvm-commits, JDevlieghere

Tags: #debug-info

Differential Revision: https://reviews.llvm.org/D39950

llvm-svn: 326056
2018-02-25 19:52:34 +00:00
Heejin Ahn 9386bde11b [WebAssembly] Add exception handling option and feature
Summary:
Add a llc command line option and WebAssembly architecture feature for
exception handling.

Reviewers: dschuff

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

Differential Revision: https://reviews.llvm.org/D43683

llvm-svn: 326004
2018-02-24 00:40:50 +00:00
Scott Linder 16c7bdaf32 [DebugInfo] Support DWARF v5 source code embedding extension
In DWARF v5 the Line Number Program Header is extensible, allowing values with
new content types. In this extension a content type is added,
DW_LNCT_LLVM_source, which contains the embedded source code of the file.

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

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

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

llvm-svn: 325970
2018-02-23 23:01:06 +00:00
Alexey Bataev bd786944b9 [DEBUGINFO] Do not output labels for empty macinfo sections.
Summary:
If there is no debug info for macros, do not emit labels for empty
macinfo sections.

Reviewers: probinson, echristo

Subscribers: aprantl, llvm-commits, JDevlieghere

Differential Revision: https://reviews.llvm.org/D43589

llvm-svn: 325803
2018-02-22 16:20:30 +00:00
Alexey Bataev 0d6aeadc40 [DEBUGINFO] Add support for emission of the inlined strings.
Summary:
Patch adds an option for emission of inlined strings rather than
.debug_str section.

Reviewers: echristo, jlebar

Subscribers: eraman, llvm-commits, JDevlieghere

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

llvm-svn: 325583
2018-02-20 15:28:08 +00:00
Pavel Labath a7c457d288 [CodeGen] Refactor AppleAccelTable
Summary:
This commit separates the abstract accelerator table data structure
from the code for writing out an on-disk representation of a specific
accelerator table format. The idea is that former (now called
AccelTable<T>) can be reused for the DWARF v5 accelerator tables
as-is, without any further customizations.

Some bits of the emission code (now living in the EmissionContext class)
can be reused for DWARF v5 as well, but the subtle differences in the
layout of various subtables mean the sharing is not always possible.
(Also, the individual emit*** functions are fairly simple so there's a
tradeoff between making a bigger general-purpose function, and two
smaller targeted functions.)

Another advantage of this setup is that more of the serialization logic
can be hidden in the .cpp file -- I have moved declarations of the
header and all the emission functions there.

Reviewers: JDevlieghere, aprantl, probinson, dblaikie

Subscribers: echristo, clayborg, vleschuk, llvm-commits

Differential Revision: https://reviews.llvm.org/D43285

llvm-svn: 325516
2018-02-19 16:12:20 +00:00
Sander de Smalen bf83be9e2a [DebugInfo] Removed assert on missing CountVarDIE
Summary:
The assert for a DISubrange's CountVarDIE to be available fails
when the dbg.value() has been optimized away for any reason.
Having the assert for that is a little heavy, so instead removing
it now in favor of not generating the 'count' expression.

Addresses http://llvm.org/PR36263 .

Reviewers: aprantl, dblaikie, probinson

Reviewed By: aprantl

Subscribers: JDevlieghere, llvm-commits, dstenb

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

llvm-svn: 325427
2018-02-17 11:06:53 +00:00
Momchil Velikov 6acc0e555b [DebugInfo] Accept enumeration types without underlying integer type present in
debug info metadata

... when generating DWARF.

Differential Revision: https://reviews.llvm.org/D43304

llvm-svn: 325234
2018-02-15 13:29:33 +00:00
Paul Robinson ee88ed6753 [DWARF] Fix incorrect prologue end line record.
The prologue-end line record must be emitted after the last
instruction that is part of the function frame setup code and before
the instruction that marks the beginning of the function body.

Patch by Carlos Alberto Enciso!

Differential Revision: https://reviews.llvm.org/D41762

llvm-svn: 325143
2018-02-14 17:35:52 +00:00
Petar Jovanovic 1768957c82 [Utils] Salvage the debug info of DCE'ed 'and' instructions
Preserve debug info from a dead 'and' instruction with a constant.

Patch by Djordje Todorovic.

Differential Revision: https://reviews.llvm.org/D43163

llvm-svn: 325119
2018-02-14 13:10:35 +00:00
Adrian Prantl 984251c7cb Document the shortcomings of DwarfExpression::addMachineReg().
Also make a drive-by-fix of a bug in the subregister scan code that
only triggers with an incomplete or otherwise very irregular machine
description.

rdar://problem/37404493

This re-applies r324972 with an early exit in the case of a complete
failure to make this commit NFC again as intended.

llvm-svn: 325041
2018-02-13 19:54:00 +00:00
Adrian Prantl c5ec51ef4f Revert "Document the shortcomings of DwarfExpression::addMachineReg()."
This reverts commit r324972. This commit broke a bot, so perhaps it is
testable after all?

llvm-svn: 324977
2018-02-13 01:17:35 +00:00
Vedant Kumar 4011c26cc7 [Utils] Salvage debug info of DCE'ed mul/sdiv/srem instructions
Here are the number of additional debug values salvaged in a stage2
build of clang:

  63 SALVAGE: MUL
  1250 SALVAGE: SDIV

(No values were salvaged from `srem` instructions in this experiment,
but it's a simple case to handle so we might as well.)

llvm-svn: 324976
2018-02-13 01:09:52 +00:00
Vedant Kumar 31ec356a48 [Utils] Salvage debug info of DCE'ed shl/lhsr/ashr instructions
Here are the number of additional debug values salvaged in a stage2
build of clang:

  1912 SALVAGE: ASHR
   405 SALVAGE: LSHR
   249 SALVAGE: SHL

llvm-svn: 324975
2018-02-13 01:09:49 +00:00
Vedant Kumar 96b7dc041b [Utils] Salvage the debug info of DCE'ed 'xor' instructions
This salvages 259 debug values in a stage2 build of clang.

Differential Revision: https://reviews.llvm.org/D43207

llvm-svn: 324973
2018-02-13 01:09:46 +00:00
Adrian Prantl eb7a85af42 Document the shortcomings of DwarfExpression::addMachineReg().
Also make a drive-by-fix of a bug in the subregister scan code that
only triggers with an incomplete or otherwise very irregular machine
description.

rdar://problem/37404493

llvm-svn: 324972
2018-02-13 01:02:56 +00:00
Scott Linder 7160384d40 [DebugInfo] Unify ChecksumKind and Checksum value in DIFile
Rather than encode the absence of a checksum with a Kind variant, instead put
both the kind and value in a struct and wrap it in an Optional.

Differential Revision: http://reviews.llvm.org/D43043

llvm-svn: 324928
2018-02-12 19:45:54 +00:00
Momchil Velikov 08dc66eff0 Re-commit r324489: [DebugInfo] Improvements to representation of enumeration types (PR36168)
Differential Revision: https://reviews.llvm.org/D42734

llvm-svn: 324899
2018-02-12 16:10:09 +00:00
Brock Wyma 19e17b3970 [CodeView] Allow variable names to be as long as the codeview format supports
Instead of reserving 0xF00 bytes for the fixed length portion of the CodeView
symbol name, calculate the actual length of the fixed length portion.

Differential Revision: https://reviews.llvm.org/D42125

llvm-svn: 324850
2018-02-11 21:26:46 +00:00
Vedant Kumar 04386d8e3d [Utils] Salvage debug info from dead 'or' instructions
Extend salvageDebugInfo to preserve the debug info from a dead 'or'
with a constant.

Patch by Ismail Badawi!

Differential Revision: https://reviews.llvm.org/D43129

llvm-svn: 324764
2018-02-09 19:19:55 +00:00
Rafael Espindola c052fa0bd3 Emit smaller exception tables for non-SJLJ mode.
* Use uleb128 for code offsets in the LSDA call site table.
* Omit the TTBase offset if the type table is empty.

This change can reduce the size of the DWARF/Itanium LSDA by about half.

Patch by Ryan Prichard!

llvm-svn: 324750
2018-02-09 17:13:37 +00:00
Rafael Espindola d09b416943 Use assembler expressions to lay out the EH LSDA.
Rely on the assembler to finalize the layout of the DWARF/Itanium
exception-handling LSDA. Rather than calculate the exact size of each
thing in the LSDA, use assembler directives:

    To emit the offset to the TTBase label:

.uleb128 .Lttbase0-.Lttbaseref0
.Lttbaseref0:

    To emit the size of the call site table:

.uleb128 .Lcst_end0-.Lcst_begin0
.Lcst_begin0:
... call site table entries ...
.Lcst_end0:

    To align the type info table:

... action table ...
.balign 4
.long _ZTIi
.long _ZTIl
.Lttbase0:

Using assembler directives simplifies the compiler and allows switching
the encoding of offsets in the call site table from udata4 to uleb128 for
a large code size savings. (This commit does not change the encoding.)

The combination of the uleb128 followed by a balign creates an unfortunate
dependency cycle that the assembler must sometimes resolve either by
padding an LEB or by inserting zero padding before the type table. See
PR35809 or GNU as bug 4029.

Patch by Ryan Prichard!

llvm-svn: 324749
2018-02-09 17:00:25 +00:00
Pavel Labath 062eb53781 [CodeGen] Optimize AccelTable
Summary:
The class contained arrays of two structures (DataArray and HashData).
These structures were in 1:1 correspondence, and one of them contained
pointers to the other (and *both* contained a "Name" field). By merging
these two structures into one, we can save a bit of space without
negatively impacting much of anything.

Reviewers: JDevlieghere, aprantl

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D43073

llvm-svn: 324724
2018-02-09 10:06:56 +00:00
Adrian Prantl 03dd6f5739 Use a stable topological sort in DwarfCompileUnit::createScopeChildrenDIE()
This addresses review feedback for D42940. The topological sort is
slightly more expensive but it can now also detect cycles in the
dependencies and actually works correctly.

rdar://problem/37217988

Differential Review: https://reviews.llvm.org/D43036

llvm-svn: 324677
2018-02-08 23:21:15 +00:00
Momchil Velikov 74906a467c Revert "[DebugInfo] Improvements to representation of enumeration types (PR36168)"
Revert commit r324489, it broke LLDB tests.

llvm-svn: 324511
2018-02-07 20:28:47 +00:00
Momchil Velikov c502027efd [DebugInfo] Improvements to representation of enumeration types (PR36168)
This patch is the LLVM part of fixing the issues, described in
https://bugs.llvm.org/show_bug.cgi?id=36168

* The representation of enumerator values in the debug info metadata now
  contains a boolean flag isUnsigned, which determines how the bits of
  the value are interpreted.
* The DW_TAG_enumeration type DIE now always (for DWARF version >= 3)
  includes a DW_AT_type attribute, which refers to the underlying
  integer type, as suggested in DWARFv4 (5.7 Enumeration Type Entries).
* The debug info metadata for enumeration type contains (in flags)
  indication whether this is a C++11 "fixed enum".
* For C++11 enumeration with a fixed underlying type, the DIE also
  includes the DW_AT_enum_class attribute (for DWARF version >= 4).
* Encoding of enumerator constants uses DW_FORM_sdata for signed values
  and DW_FORM_udata for unsigned values, as suggested by DWARFv4 (7.5.4
  Attribute Encodings).

The changes should be backwards compatible:

* the isUnsigned attribute is optional and defaults to false.
* if the underlying type for the enumeration is not available, the
  enumerator values are considered signed.
* the FixedEnum flag defaults to clear.
* the bitcode format for DIEnumerator stores the unsigned flag bit #1 of
  the first record element, so the format does not change and the zero
  previously stored there is consistent with the false default for
  IsUnsigned.

Differential Revision: https://reviews.llvm.org/D42734

llvm-svn: 324489
2018-02-07 16:46:33 +00:00
Adrian Prantl 8c59921ca3 Add DWARF for discriminated unions
n Rust, an enum that carries data in the variants is, essentially, a
discriminated union. Furthermore, the Rust compiler will perform
space optimizations on such enums in some situations. Previously,
DWARF for these constructs was emitted using a hack (a magic field
name); but this approach stopped working when more space optimizations
were added in https://github.com/rust-lang/rust/pull/45225.

This patch changes LLVM to allow discriminated unions to be
represented in DWARF. It adds createDiscriminatedUnionType and
createDiscriminatedMemberType to DIBuilder and then arranges for this
to be emitted using DWARF's DW_TAG_variant_part and DW_TAG_variant.

Note that DWARF requires that a discriminated union be represented as
a structure with a variant part. However, as Rust only needs to emit
pure discriminated unions, this is what I chose to expose on
DIBuilder.

Patch by Tom Tromey!

Differential Revision: https://reviews.llvm.org/D42082

llvm-svn: 324426
2018-02-06 23:45:59 +00:00
Adrian Prantl c929f7ad42 Fix a crash when emitting DIEs for variable-length arrays
VLAs may refer to a previous DIE to express the DW_AT_count of their
type. Clang generates an artificial "vla_expr" variable for this. If
this DIE hasn't been created yet LLVM asserts. This patch fixes this
by sorting the local variables so that dependencies come before they
are needed. It also replaces the linear scan in DWARFFile with a
std::map, which can be faster.

Differential Revision: https://reviews.llvm.org/D42940

llvm-svn: 324412
2018-02-06 22:17:45 +00:00
Brock Wyma 4536c1f569 [CodeView] Class record member counts should include base classes and ...
Increment the field list member count for base classes and virtual base
classes.

Differential Revision: https://reviews.llvm.org/D41874

llvm-svn: 324000
2018-02-01 20:37:38 +00:00
Jonas Devlieghere 1ce64dcc64 [AccelTable] Move print methods to implementation. NFC
This patch moves the implementation of the print methods from the header
to the cpp file.

llvm-svn: 323757
2018-01-30 13:36:30 +00:00
Brock Wyma 31cc1ebbc6 Test commit.
As per the LLVM Developer Policy under "Obtainiing Commit Access".

llvm-svn: 323754
2018-01-30 13:16:50 +00:00
Shoaib Meenai 63b6a0e5bc [CodeGen] Simplify conditional. NFC
Rafael pointed out that `hasInternalLinkage() || hasPrivateLinkage()` is
equivalent to `hasLocalLinkage()` in post-commit review.

I'm intentionally not updating the comment, partly because I like it
being explicit, and partly because "global symbols with local linkage"
sounds like an oxymoron.

llvm-svn: 323688
2018-01-29 20:28:04 +00:00
Jonas Devlieghere 073971b243 [AccelTable] Workaround for MSVC bug
Microsoft Visual Studio rejects the static constexpr static list of
atoms even though it's valid C++. This provides a workaround to unbreak
the bots.

llvm-svn: 323667
2018-01-29 17:28:51 +00:00
Jonas Devlieghere ba8daf0964 [AccelTable] Try making MSVC happy
MSVC complains that the constexpr "expression did not evaluate to a
constant". Trying to make it happy by adding a `const` specifier as
suggested in https://stackoverflow.com/questions/37574343.

llvm-svn: 323659
2018-01-29 15:23:34 +00:00
Jonas Devlieghere 5ead3a2b07 [dsymutil] Generate Apple accelerator tables
This patch adds support for generating accelerator tables in dsymutil.
This feature was already present in our internal repository but not yet
upstreamed because it requires changes to the Apple accelerator table
implementation.

Differential revision: https://reviews.llvm.org/D42501

llvm-svn: 323655
2018-01-29 14:52:50 +00:00
Jonas Devlieghere 855fc3bbca [NFC] Rename DwarfAccelTable and move header.
This patch renames DwarfAccelTable.{h,cpp} to AccelTable.{h,cpp} and
moves the header to the include dir so it is accessible by the
dsymutil implementation.

Differential revision: https://reviews.llvm.org/D42529

llvm-svn: 323654
2018-01-29 14:52:41 +00:00
Jonas Devlieghere e699dfaa7a [NFC] Refactor Apple Accelerator Tables
This patch refactors the way data is stored in the accelerator table and
makes them truly generic. There have been several attempts to do this in
the past:

 - D8215 & D8216: Using a union and partial hardcoding.
 - D11805: Using inheritance.
 - D42246: Using a callback.

In the end I didn't like either of them, because for some reason or
another parts of it felt hacky or decreased runtime performance. I
didn't want to completely rewrite them as I was hoping that we could
reuse parts for the successor in the DWARF standard. However, it seems
less and less likely that there will be a lot of opportunities for
sharing code and/or an interface.

Originally I choose to template the whole class, because it introduces
no performance overhead compared to the original implementation.

We ended up settling on a hybrid between a templated method and a
virtual call to emit the data. The motivation is that we don't want to
increase code size for a feature that should soon be superseded by the
DWARFv5 accelerator tables. While the code will continue to be used for
compatibility, it won't be on the hot path. Furthermore this does not
regress performance compared to Apple's internal implementation that
already uses virtual calls for this.

A quick summary for why these changes are necessary: dsymutil likes to
reuse the current implementation of the Apple accelerator tables.
However, LLDB expects a slightly different interface than what is
currently emitted. Additionally, in dsymutil we only have offsets and no
actual DIEs.

Although the patch suggests a lot of code has changed, this change is
pretty straightforward:

 - We created an abstract class `AppleAccelTableData` to serve as an
   interface for the different data classes.
 - We created two implementations of this class, one for type tables and
   one for everything else. There will be a third one for dsymutil that
   takes just the offset.
 - We use the supplied class to deduct the atoms for the header which
   makes the structure of the table fully self contained, although not
   enforced by the interface as was the case for the fully templated
   approach.
 - We renamed the prefix from DWARF- to Apple- to make space for the
   future implementation of .debug_names.

This change is NFC and relies on the existing tests.

Differential revision: https://reviews.llvm.org/D42334

llvm-svn: 323653
2018-01-29 14:52:34 +00:00
Mikael Holmen a9e31537af [DebugInfo] Fix fragment offset emission order for symbol locations
Summary:
When emitting the location for a global variable with fragmented debug
expressions, make sure that the offset pieces, which represent
optimized-out parts of the variable, are emitted before their succeeding
fragments' expressions. Previously, if the succeeding fragment's
location was a symbol, the offset piece was emitted after, rather than
before, that symbol's expression. This effectively meant that the symbols
were associated with the wrong parts of the variable.

This fixes PR36085.

Patch by: David Stenberg

Reviewers: aprantl, probinson, dblaikie

Reviewed By: aprantl

Subscribers: JDevlieghere, llvm-commits

Tags: #debug-info

Differential Revision: https://reviews.llvm.org/D42527

llvm-svn: 323644
2018-01-29 12:37:30 +00:00
Jonas Devlieghere 92ac9d3e1b [Support] Move DJB hash to support. NFC
This patch moves the DJB hash to support. This is consistent with other
hashing algorithms living there. The hash is used by the DWARF
accelerator tables. We're doing this now because the hashing function is
needed by dsymutil and we don't want to link against libBinaryFormat.

Differential revision: https://reviews.llvm.org/D42594

llvm-svn: 323616
2018-01-28 11:05:10 +00:00
Wolfgang Pieb 456b555ffe [DWARF] Generate DWARF v5 string offsets tables along with strx* index forms.
Summary: This is the producer side for DWARF v5 string offsets tables. The reader/consumer
side was committed with r321295. All compile and type units in a module share a 
contribution to the string offsets table. Indirect strings use the strx{1,2,3,4} index forms.

Reviewers: dblaikie, aprantl, JDevliegehere

Differential Revision: https://reviews.llvm.org/D42021

llvm-svn: 323546
2018-01-26 18:52:58 +00:00
Hiroshi Inoue 0909ca132f [NFC] fix trivial typos in comments and documents
"in in" -> "in", "on on" -> "on" etc.

llvm-svn: 323508
2018-01-26 08:15:29 +00:00
Shoaib Meenai d8fd16b08f [CodeGen] Ignore private symbols in llvm.used for COFF
Similar to the existing handling for internal symbols, private symbols
are also not visible to the linker and should be ignored.

llvm-svn: 323483
2018-01-26 00:15:25 +00:00
Sander de Smalen dc00becd1b [DebugInfo] Emit DWARF reference for DIVariable 'count' in DISubrange
Summary:
This patch implements the codegen of DWARF debug info for non-constant
'count' fields for DISubrange.

This is patch [2/3] in a series to extend LLVM's DISubrange Metadata
node to support debugging of C99 variable length arrays and vectors with
runtime length like the Scalable Vector Extension for AArch64. It is
also a first step towards representing more complex cases like arrays
in Fortran.

Reviewers: echristo, pcc, aprantl, dexonsmith, clayborg, kristof.beyls, dblaikie

Reviewed By: aprantl

Subscribers: fhahn, aemerson, rengolin, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D41696

llvm-svn: 323323
2018-01-24 13:35:54 +00:00
Sander de Smalen fdf40917d9 [Metadata] Extend 'count' field of DISubrange to take a metadata node
Summary:
This patch extends the DISubrange 'count' field to take either a
(signed) constant integer value or a reference to a DILocalVariable
or DIGlobalVariable.

This is patch [1/3] in a series to extend LLVM's DISubrange Metadata
node to support debugging of C99 variable length arrays and vectors with
runtime length like the Scalable Vector Extension for AArch64. It is
also a first step towards representing more complex cases like arrays
in Fortran.

Reviewers: echristo, pcc, aprantl, dexonsmith, clayborg, kristof.beyls, dblaikie

Reviewed By: aprantl

Subscribers: rnk, probinson, fhahn, aemerson, rengolin, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D41695

llvm-svn: 323313
2018-01-24 09:56:07 +00:00
Saleem Abdulrasool 99f479abcf CodeGen: handle llvm.used properly for COFF
`llvm.used` contains a list of pointers to named values which the
compiler, assembler, and linker are required to treat as if there is a
reference that they cannot see.  Ensure that the symbols are preserved
by adding an explicit `-include` reference to the linker command.

llvm-svn: 323017
2018-01-20 00:28:02 +00:00
Reid Kleckner 1aa9061c5f [CodeGen] Hoist common AsmPrinter code out of X86, ARM, and AArch64
Every known PE COFF target emits /EXPORT: linker flags into a .drective
section. The AsmPrinter should handle this.

While we're at it, use global_values() and emit each export flag with
its own .ascii directive. This should make the .s file output more
readable.

llvm-svn: 322788
2018-01-17 23:55:23 +00:00
Pavel Labath 67530e478b Don't emit apple accelerator tables on non-darwin targets
Summary:
Currently -glldb turns on emission of apple tables on all targets, but
lldb is only really capable of consuming them on darwin. Furthermore,
making lldb consume these tables is not straight-forward because of the
differences in how the debug info is distributed on darwin vs. elf
targets.

The darwin debug model assumes that the debug info (along with
accelerator tables) will either remain in the .o files or it will be
linked into a dsym bundle by a linker that knows how to merge these
tables. In the elf world, all present linkers will simply concatenate
these accelerator tables into the shared object. Since the tables are
not self-terminating, this renders the tables unusable, as the debugger
cannot pry the individual tables apart anymore.

It might theoretically be possible to make the tables work with split
dwarf, as that is somewhat similar to the apple .o model, but
unfortunately right now the combination of -glldb and -gsplit-dwarf
produces broken object files.

Until these issues are resolved there is no point in emitting the apple
tables for these targets. At best, it wastes space; at worst, it breaks
compilation and prevents the user from getting other benefits of -glldb.

Reviewers: probinson, aprantl, dblaikie

Subscribers: emaste, dim, llvm-commits, JDevlieghere

Differential Revision: https://reviews.llvm.org/D41986

llvm-svn: 322633
2018-01-17 11:52:13 +00:00
Sean Eveson 2ae6037dd1 [MC] Fix -stack-size-section on ARM
Change symbol values in the stack_size section from being 8 bytes, to being a target dependent size.

Differential Revision: https://reviews.llvm.org/D42108

llvm-svn: 322619
2018-01-17 09:01:29 +00:00
Paul Robinson 612e89d74f [DWARFv5] CodeGen support for MD5 file checksums
Pass MD5 checksums through from IR to assembly/object files.
After this, getting Clang to compute the MD5 should be the last step
to supporting MD5 in the DWARF v5 line table header.

Differential Revision: https://reviews.llvm.org/D41926

llvm-svn: 322391
2018-01-12 19:17:50 +00:00
Aaron Smith a73fa2a0ed [CodeView] Fix the type for a variadic argument
Summary:
- MSVC uses the none type for a variadic argument in CodeView
- Add a unit test

Reviewers: zturner, llvm-commits

Reviewed By: zturner

Differential Revision: https://reviews.llvm.org/D41931

llvm-svn: 322257
2018-01-11 06:42:11 +00:00
Wolfgang Pieb 20a745375c [DWARF][NFC] Overload AsmPrinter::emitDwarfStringOffsets() to take a DwarfStringPoolEntry
record.

Differential Revision: https://reviews.llvm.org/D41920

llvm-svn: 322250
2018-01-11 02:35:00 +00:00
Adrian McCarthy db2736ddd8 Reland "Emit Function IDs table for Control Flow Guard"
Adds option /guard:cf to clang-cl and -cfguard to cc1 to emit function IDs
of functions that have their address taken into a section named .gfids$y for
compatibility with Microsoft's Control Flow Guard feature.

The original patch didn't have the lit.local.cfg file that restricts the new
test to x86, thus the new test was failing on the non-x86 bots.

Differential Revision: https://reviews.llvm.org/D40531

The reverts r322008, which was a revert of r322005.

This reverts commit a05b89f9aca70597dc79fe97bc49b50b51f525ba.

llvm-svn: 322136
2018-01-09 23:49:30 +00:00
Paul Robinson 29f5f987f1 [DWARFv5] MC support for MD5 file checksums
Extend .file directive syntax to allow specifying an MD5 checksum for
the source file.  Emit the checksums in DWARF v5 line tables.

llvm-svn: 322134
2018-01-09 23:31:48 +00:00
Eric Christopher d72f78e7c8 Tidy some grammar in some comments
llvm-svn: 322133
2018-01-09 23:25:38 +00:00
Adrian McCarthy ce63a925cc Revert "Emit Function IDs table for Control Flow Guard"
The new test fails on the Hexagon bot.  Reverting while I investigate.

This reverts https://reviews.llvm.org/rL322005

This reverts commit b7e0026b4385180c378edc658ec91a39566f2942.

llvm-svn: 322008
2018-01-08 17:12:01 +00:00
Adrian McCarthy cf6e6c82c1 Emit Function IDs table for Control Flow Guard
Adds option /guard:cf to clang-cl and -cfguard to cc1 to emit function IDs
of functions that have their address taken into a section named .gfids$y for
compatibility with Microsoft's Control Flow Guard feature.

Differential Revision: https://reviews.llvm.org/D40531

llvm-svn: 322005
2018-01-08 16:33:42 +00:00
Adrian McCarthy 74bfafa10e Re-land "Fix faulty assertion in debug info"
This had been reverted because the new test failed on non-X86 bots.  I moved
the new test to the appropriate subdirectory to correct this.

Differential Revision: https://reviews.llvm.org/D41264
Original submission:  r321122 (which was reverted by r321125)

This reverts commit 3c1639b5703c387a0d8cba2862803b4e68dff436.

llvm-svn: 321911
2018-01-05 23:01:04 +00:00
Bjorn Pettersson 5ffb1c0ff0 [DebugInfo] Align comments in debug_loc section
Summary:
This commit updates the BufferByteStreamer, used by DebugLocStream
to buffer bytes/comments to put in the debug_loc section, to
make sure that the Buffer and Comments vectors are synced.
Previously, when an SLEB128 or ULEB128 was emitted together with
a comment, the vectors could be out-of-sync if the LEB encoding
added several entries to the Buffer vectors, while we only added
a single entry to the Comments vector.

The goal with this is to get the comments in the debug_loc
section in the .s file correctly aligned.

Example (using ARM as target):
Instead of

  .byte 144                     @ sub-register DW_OP_regx
  .byte 128                     @ 256
  .byte 2                       @ DW_OP_piece
  .byte 147                     @ 8
  .byte 8                       @ sub-register DW_OP_regx
  .byte 144                     @ 257
  .byte 129                     @ DW_OP_piece
  .byte 2                       @ 8
  .byte 147                     @
  .byte 8                       @

we now get

  .byte 144                     @ sub-register DW_OP_regx
  .byte 128                     @ 256
  .byte 2                       @
  .byte 147                     @ DW_OP_piece
  .byte 8                       @ 8
  .byte 144                     @ sub-register DW_OP_regx
  .byte 129                     @ 257
  .byte 2                       @
  .byte 147                     @ DW_OP_piece
  .byte 8                       @ 8

Reviewers: JDevlieghere, rnk, aprantl

Reviewed By: aprantl

Subscribers: davide, Ka-Ka, uabelho, aemerson, javed.absar, kristof.beyls, llvm-commits, JDevlieghere

Differential Revision: https://reviews.llvm.org/D41763

llvm-svn: 321907
2018-01-05 22:20:30 +00:00
Adrian Prantl a29aac7b77 Debug Info: Support DW_AT_calling_convention on composite types.
This implements the DWARF 5 feature described at
http://www.dwarfstd.org/ShowIssue.php?issue=141215.1

This allows a consumer to understand whether a composite data type is
trivially copyable and thus should be passed by value instead of by
reference. The canonical example is being able to distinguish the
following two types:

  // S is not trivially copyable because of the explicit destructor.
  struct S {
     ~S() {}
  };

  // T is a POD type.
  struct T {
     ~T() = default;
  };

This patch adds two new (DI)flags to LLVM metadata: TypePassByValue
and TypePassByReference.

<rdar://problem/36034922>
Differential Revision: https://reviews.llvm.org/D41743

llvm-svn: 321844
2018-01-05 01:13:37 +00:00
Adrian McCarthy 86795d9166 Revert "Fix faulty assertion in debug info"
This reverts commit e32def3f7ebe1136b7038336eff56a415a962bf2.

llvm-svn: 321125
2017-12-19 23:34:37 +00:00
Adrian McCarthy 2ed8f36834 Fix faulty assertion in debug info
It appears the code uses nullptr to represent a void type in debug metadata,
which led to an assertion failure when building DeltaAlgorithm.cpp with a
self-hosted clang on Windows.

I'm not sure why/if the problem was Windows-specific.

Fixes bug https://bugs.llvm.org/show_bug.cgi?id=35543

Differential Revision: https://reviews.llvm.org/D41264

llvm-svn: 321122
2017-12-19 23:01:17 +00:00
Adrian Prantl 0e6694d111 Silence a bunch of implicit fallthrough warnings
llvm-svn: 321114
2017-12-19 22:05:25 +00:00
Paul Robinson a06f8dcca6 Recommit "[DWARFv5] Dump an MD5 checksum in the line-table header."
Adds missing support for DW_FORM_data16.

Update of r320852/r320886, fixing the unittest again, this time use a
raw char string for the test data.

Differential Revision: https://reviews.llvm.org/D41090

llvm-svn: 321011
2017-12-18 19:08:35 +00:00
Paul Robinson 6d0484f2b6 Revert "Recommit "[DWARFv5] Dump an MD5 checksum in the line-table header.""
This reverts commit 0afef672f63f0e4e91938656bc73424a8c058bfc.
Still failing at runtime on bots.

llvm-svn: 320888
2017-12-15 23:21:52 +00:00
Paul Robinson 5c8f7d7de4 Recommit "[DWARFv5] Dump an MD5 checksum in the line-table header."
Adds missing support for DW_FORM_data16.

Update of r320852, fixing the unittest to use a hand-coded struct
instead of std::array to guarantee data layout.

Differential Revision: https://reviews.llvm.org/D41090

llvm-svn: 320886
2017-12-15 22:57:17 +00:00
Matthias Braun f1caa2833f MachineFunction: Return reference from getFunction(); NFC
The Function can never be nullptr so we can return a reference.

llvm-svn: 320884
2017-12-15 22:22:58 +00:00
Paul Robinson 67ca67d1b2 Revert "[DWARFv5] Dump an MD5 checksum in the line-table header."
Unit test fails on some bots.

llvm-svn: 320857
2017-12-15 20:29:25 +00:00
Paul Robinson 72546fe87b [DWARFv5] Dump an MD5 checksum in the line-table header.
Adds missing support for DW_FORM_data16.

Differential Revision: https://reviews.llvm.org/D41090

llvm-svn: 320852
2017-12-15 19:52:34 +00:00
Andrew V. Tischenko 22f0742dda Fix for bug PR35549 - Repeated schedule comments.
Differential Revision: https://reviews.llvm.org/D40960

llvm-svn: 320837
2017-12-15 18:13:05 +00:00
Matthias Braun 5dd72adbec MC/AsmPrinter: Reduce code duplication.
Factor out duplicated code emitting mach-o version-min specifiers.

This should be NFC but happens to fix a bug where the code in
MCMachoStreamer didn't take the version skew between darwin and macos
versions into account.

llvm-svn: 320666
2017-12-14 03:59:24 +00:00
Zachary Turner 048f8f99bf [CodeView] Teach clang to emit the .debug$H COFF section.
Currently this is an LLVM extension to the COFF spec which is
experimental and intended to speed up linking.  For now it is
behind a hidden cl::opt flag, but in the future we can move it
to a "real" cc1 flag and have the driver pass it through whenever
it is appropriate.

The patch to actually make use of this section in lld will come
in a followup.

Differential Revision: https://reviews.llvm.org/D40917

llvm-svn: 320649
2017-12-13 22:33:58 +00:00