Commit Graph

318 Commits

Author SHA1 Message Date
Yuanfang Chen 6e24c6037f Revert "[Support] make report_fatal_error `abort` instead of `exit`"
This reverts commit 647c3f4e47.

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

** The reason it fixes PR35547 is

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

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

Reviewed By: rnk, MaskRay

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

Tags: #llvm, #clang

Differential Revision: https://reviews.llvm.org/D67847
2020-01-15 17:05:13 -08:00
Fangrui Song ebd26cc8c4 [PowerPC] Delete PPCDarwinAsmPrinter and PPCMCAsmInfoDarwin
Darwin support has been removed.

Reviewed By: nemanjai

Differential Revision: https://reviews.llvm.org/D72063
2020-01-12 11:02:02 -08:00
Fangrui Song 502a77f125 Migrate function attribute "no-frame-pointer-elim" to "frame-pointer"="all" as cleanups after D56351 2019-12-24 15:57:33 -08:00
Michael Trent 6f95d33e2b [ MC ] Match labels to existing fragments even when switching sections.
(This commit restores the original branch (4272372c57) and applies an
additional change dropped from the original in a bad merge. This change
should address the previous bot failures. Both changes reviewed by pete.)

Summary:
This commit builds upon Derek Schuff's 2014 commit for attaching labels to
existing fragments ( Diff Revision: http://reviews.llvm.org/D5915 )

When temporary labels appear ahead of a fragment, MCObjectStreamer will
track the temporary label symbol in a "Pending Labels" list. Labels are
associated with fragments when a real fragment arrives; otherwise, an empty
data fragment will be created if the streamer's section changes or if the
stream finishes.

This commit moves the "Pending Labels" list into each MCStream, so that
this label-fragment matching process is resilient to section changes. If
the streamer emits a label in a new section, switches to another section to
do other work, then switches back to the first section and emits a
fragment, that initial label will be associated with this new fragment.
Labels will only receive empty data fragments in the case where no other
fragment exists for that section.

The downstream effects of this can be seen in Mach-O relocations. The
previous approach could produce local section relocations and external
symbol relocations for the same data in an object file, and this mix of
relocation types resulted in problems in the ld64 Mach-O linker. This
commit ensures relocations triggered by temporary labels are consistent.

Reviewers: pete, ab, dschuff

Reviewed By: pete, dschuff

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71368
2019-12-18 09:55:54 -08:00
Mitch Phillips f827aff859 Revert "[ MC ] Match labels to existing fragments even when switching sections."
This reverts commit 4272372c57.

Caused an MSan buildbot failure. More information available in the patch
that introduced the bug: https://reviews.llvm.org/D71368
2019-12-17 15:04:26 -08:00
Michael Trent 4272372c57 [ MC ] Match labels to existing fragments even when switching sections.
Summary:
This commit builds upon Derek Schuff's 2014 commit for attaching labels to
existing fragments ( Diff Revision: http://reviews.llvm.org/D5915 )

When temporary labels appear ahead of a fragment, MCObjectStreamer will
track the temporary label symbol in a "Pending Labels" list. Labels are
associated with fragments when a real fragment arrives; otherwise, an empty
data fragment will be created if the streamer's section changes or if the
stream finishes.

This commit moves the "Pending Labels" list into each MCStream, so that
this label-fragment matching process is resilient to section changes. If
the streamer emits a label in a new section, switches to another section to
do other work, then switches back to the first section and emits a
fragment, that initial label will be associated with this new fragment.
Labels will only receive empty data fragments in the case where no other
fragment exists for that section.

The downstream effects of this can be seen in Mach-O relocations. The
previous approach could produce local section relocations and external
symbol relocations for the same data in an object file, and this mix of
relocation types resulted in problems in the ld64 Mach-O linker. This
commit ensures relocations triggered by temporary labels are consistent.

Reviewers: pete, ab, dschuff

Reviewed By: pete, dschuff

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71368
2019-12-17 08:49:25 -08:00
Alexey Lapshin e73f78acd3 [X86][MC] no error diagnostic for out-of-range jrcxz/jecxz/jcxz
Fix for PR24072:

X86 instructions jrcxz/jecxz/jcxz performs short jumps if rcx/ecx/cx register is 0
The maximum relative offset for a forward short jump is 127 Bytes (0x7F).
The maximum relative offset for a backward short jump is 128 Bytes (0x80).

Gnu assembler warns when the distance of the jump exceeds the maximum but llvm-as does not.

Patch by Konstantin Belochapka and Alexey Lapshin

Differential Revision: https://reviews.llvm.org/D70652
2019-11-26 14:32:17 +03:00
Francis Visoiu Mistrih 5b5ee61b5f [MachO][TLOF] Use hasLocalLinkage to determine if indirect symbol is local
Local symbols in the indirect symbol table contain the value
`INDIRECT_SYMBOL_LOCAL` and the corresponding __pointers entry must
contain the address of the target.

In r349060, I added support for local symbols in the indirect symbol
table, which was checking if the symbol `isDefined` && `!isExternal` to
determine if the symbol is local or not.

It turns out that `isDefined` will return false if the user of the
symbol comes before its definition, and we'll again generate .long 0
which will be the symbol at the adress 0x0.

Instead of doing that, use GlobalValue::hasLocalLinkage() to check if
the symbol is local.

Differential Revision: https://reviews.llvm.org/D66563

llvm-svn: 369671
2019-08-22 16:59:00 +00:00
Seiya Nuta 0a3b1b2628 [llvm-readobj][MachO] Fix section type printing
Summary:
Currently, llvm-readobj mistakenly decodes section type as section attribute.

This patch fixes the bug and affected tests.

Reviewers: JDevlieghere, jhenderson, rupprecht, alexshap, echristo

Reviewed By: jhenderson, rupprecht, alexshap, echristo

Subscribers: javed.absar, rupprecht, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66075

llvm-svn: 368974
2019-08-15 07:22:04 +00:00
Alex Lorenz 6d187f0eff [macCatalyst] Use macCatalyst pretty name in .build_version darwin
assembly command

'macCatalyst' is more readable than 'maccatalyst'. I renamed the objdump output,
but the assembly should match it as well.

llvm-svn: 365964
2019-07-12 22:06:08 +00:00
Alex Lorenz b853fa6bff [macCatalyst] Print out macCatalyst in llvm-objdump for the platform
'macCatalyst' is more readable than 'maccatalyst'.

llvm-svn: 365064
2019-07-03 17:46:30 +00:00
Alex Lorenz 3dbdbbec84 [triple] Use 'macabi' environment name for the Mac Catalyst triples
The 'macabi' environment name is preferred instead of 'maccatalyst'.

llvm-svn: 364988
2019-07-03 01:02:43 +00:00
Alex Lorenz da1dfecd32 Add support for the 'macCatalyst' MachO platform
Mac Catalyst is a new MachO platform in macOS Catalina.
It always uses the build_version MachO load command.

Differential Revision: https://reviews.llvm.org/D64107

llvm-svn: 364981
2019-07-02 23:47:11 +00:00
Fangrui Song ac14f7b10c [lit] Delete empty lines at the end of lit.local.cfg NFC
llvm-svn: 363538
2019-06-17 09:51:07 +00:00
Paul Robinson 35a2196bd1 Fix typo in r361251.
llvm-svn: 361256
2019-05-21 13:23:32 +00:00
Paul Robinson 0a16ba856b [DebugInfo] Fix tests missed by r362148
llvm-svn: 361251
2019-05-21 12:48:46 +00:00
Fangrui Song 6afcdcf9ab [llvm-readobj] Change -t to --symbols in tests. NFC
-t is --symbols in llvm-readobj but --section-details (unimplemented) in readelf.
The confusing option should not be used since we aim for improving
compatibility.

Keep just one llvm-readobj -t use case in test/tools/llvm-readobj/symbols.test

llvm-svn: 359661
2019-05-01 09:28:24 +00:00
Fangrui Song e29e30b139 [llvm-readobj] Change -long-option to --long-option in tests. NFC
We use both -long-option and --long-option in tests. Switch to --long-option for consistency.

In the "llvm-readelf" mode, -long-option is discouraged as it conflicts with grouped short options and it is not accepted by GNU readelf.

While updating the tests, change llvm-readobj -s to llvm-readobj -S to reduce confusion ("s" is --section-headers in llvm-readobj but --symbols in llvm-readelf).

llvm-svn: 359649
2019-05-01 05:27:20 +00:00
Francis Visoiu Mistrih c01140ef1f [MC][MachO] Emit an error for emitting relocations of the form -SYM + cst
Emit an error for an unsupported relocation. mach-o relocations can't
encode the form -SYM + cst.

Differential Revision: https://reviews.llvm.org/D58944

llvm-svn: 355527
2019-03-06 18:10:41 +00:00
Reid Kleckner f38bc4fc99 [MC] Don't error on numberless .file directives on MachO
Summary:
Before r349976, MC ignored such directives when producing an object file
and asserted when re-producing textual assembly output. I turned this
assertion into a hard error in both cases in r349976, but this makes it
unnecessarily difficult to write a single assembly file that supports
both MachO and other object formats that support .file. A user reported
this as PR40578, and we decided to go back to ignoring the directive.

Fixes PR40578

Reviewers: mstorsjo

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D57772

llvm-svn: 353218
2019-02-05 21:14:09 +00:00
Reid Kleckner 98bbd07cc3 [MC] Enable .file support on COFF and diagnose it on unsupported targets
Summary:
The "single parameter" .file directive appears to be an ELF-only feature
that is intended to insert the main source filename into the string
table table.

I noticed that if you assemble an ELF .s file for COFF, typically it
will assert right away on a .file directive near the top of the file. My
first change was to make this emit a proper error in the asm parser so
that we don't assert so easily.

However, COFF actually does have some support for this directive, and if
you emit an object file, llvm-mc does not assert. When emitting a COFF
object, MC will take those file names and create "debug" symbol table
entries for them. I'm not familiar with these kinds of symbol table
entries, and I'm not aware of any users of them, but @compnerd added
them a while ago. They don't introduce absolute paths, and most main
source file paths are short enough that this extra entry shouldn't cause
any problems, so I enabled the flag in MCAsmInfoCOFF that indicates that
it's supported.

This has the side effect of adding an extra debug symbol to every object
produced by clang, which is a pretty big functional change. My question
is, should we keep the functionality or remove it in the name of symbol
table minimalism?

Reviewers: mstorsjo, compnerd

Subscribers: hiraditya, compnerd, llvm-commits

Differential Revision: https://reviews.llvm.org/D55900

llvm-svn: 349976
2018-12-21 23:35:48 +00:00
Alex Lorenz afa75d7843 [macho] save the SDK version stored in module metadata into the version min and
build version load commands in the object file

This commit introduces a new metadata node called "SDK Version". It will be set
by the frontend to mark the platform SDK (macOS/iOS/etc) version which was used
during that particular compilation.
This node is used when machine code is emitted, by either saving the SDK version
into the appropriate macho load command (version min/build version), or by
emitting the assembly for these load commands with the SDK version specified as
well.
The assembly for both load commands is extended by allowing it to contain the
sdk_version X, Y [, Z] trailing directive to represent the SDK version
respectively.

rdar://45774000

Differential Revision: https://reviews.llvm.org/D55612

llvm-svn: 349119
2018-12-14 01:14:10 +00:00
Francis Visoiu Mistrih 91e69d8a92 [MachO][TLOF] Add support for local symbols in the indirect symbol table
On 32-bit archs, before, we would assume that an indirect symbol will
never have local linkage. This can lead to miscompiles where the
symbol's value would be 0 and the linker would use that value, because
the indirect symbol table would contain the value
`INDIRECT_SYMBOL_LOCAL` for that specific symbol.

Differential Revision: https://reviews.llvm.org/D55573

llvm-svn: 349060
2018-12-13 17:23:30 +00:00
Jonas Devlieghere ccf7d4b4aa Produce an error on non-encodable offsets for darwin ARM scattered relocations.
Scattered ARM relocations for Mach-O's only have 24 bits available to
encode the offset. This is not checked but just truncated and can result
in corrupt binaries after linking because the relocations are applied to
the wrong offset. This patch will check and error out in those
situations instead of emitting a wrong relocation.

Patch by: Sander Bogaert (dzn)

Differential revision: https://reviews.llvm.org/D54776

llvm-svn: 347922
2018-11-29 21:58:23 +00:00
Jonas Devlieghere 64c901d2b1 [MC/Dwarf] Unclamp DWARF linetables format on Darwin.
In r319995, we fixed the line table format to version 2 on Darwin
because dsymutil didn't yet understand the new format which caused test
failures for the LLDB bots. This has been resolved in the meantime so
there's no reason to keep this limitation.

rdar://problem/35968332

llvm-svn: 342136
2018-09-13 13:13:50 +00:00
Francis Visoiu Mistrih 4d5b1073ba [MC] Error on a .zerofill directive in a non-virtual section
On darwin, all virtual sections have zerofill type, and having a
.zerofill directive in a non-virtual section is not allowed. Instead of
asserting, show a nicer error.

In order to use the equivalent of .zerofill in a non-virtual section,
the usage of .zero of .space is required.

This patch replaces the assert with an error.

Differential Revision: https://reviews.llvm.org/D48517

llvm-svn: 336127
2018-07-02 17:29:43 +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
Tim Northover 271d3d2771 MachO: trap unreachable instructions
Debugability is more important than saving 4 bytes to let us to fall
through to nonense.

llvm-svn: 330073
2018-04-13 22:25:20 +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
Paul Robinson 7b98be2c19 Fix regex from r324279 more better.
llvm-svn: 324298
2018-02-06 00:43:26 +00:00
Paul Robinson ea27528b0a Fix Windows bots for test from r324270.
llvm-svn: 324279
2018-02-05 22:30:00 +00:00
Paul Robinson 0a22709f06 [DWARF] Regularize dumping strings from line tables.
The major visible difference here is that in line-table dumps,
directory and file names are wrapped in double-quotes; previously,
directory names got single quotes and file names were not quoted at
all.

The improvement in this patch is that when a DWARF v5 line table
header has indirect strings, in a verbose dump these will all have
their section[offset] printed as well as the name itself.  This
matches the format used for dumping strings in the .debug_info
section.

Differential Revision: https://reviews.llvm.org/D42802

llvm-svn: 324270
2018-02-05 20:43:15 +00:00
Simon Pilgrim 02bdac53e7 [X86] Emit 11-byte or 15-byte NOPs on recent AMD targets, else default to 10-byte NOPs (PR22965)
We currently emit up to 15-byte NOPs on all targets (apart from Silvermont), which stalls performance on some targets with decoders that struggle with 2 or 3 more '66' prefixes.

This patch flags recent AMD targets (btver1/znver1) to still emit 15-byte NOPs and bdver* targets to emit 11-byte NOPs. All other targets now emit 10-byte NOPs apart from SilverMont CPUs which still emit 7-byte NOPS.

Differential Revision: https://reviews.llvm.org/D42616

llvm-svn: 323693
2018-01-29 21:24:31 +00:00
Craig Topper 4802d4e23e [X86] Don't use NOPL when the assembler is passed an empty CPU string. Update tests to force a CPU with NOPL
Empty string should be equivalent to "generic" which doesn't allow NOPL. Force tests to use specificy 'pentiumpro' to guarantee NOPL.

Fixes PR35686

llvm-svn: 321026
2017-12-18 21:37:27 +00:00
Paul Robinson a1cedd6c46 [MC] Allow .file directives to be out-of-order
llvm-svn: 320727
2017-12-14 18:46:43 +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
Matthias Braun 0148c88c08 MC: Add support for mach-o build_version
LC_BUILD_VERSION is a new load command superseding the previously used
LC_XXX_MIN_VERSION commands. This adds an assembler directive along with
encoding/streaming support.

llvm-svn: 320661
2017-12-14 00:12:46 +00:00
Davide Italiano 23b3f6da14 [MC/Dwarf] Use the older DWARF linetables format on Darwin.
dsymutil doesn't yet understand the new format and the change,
among others, breaks a large fraction of the debugger tests on
mac OS.

rdar://problem/35856354

llvm-svn: 319995
2017-12-07 00:57:25 +00:00
Paul Robinson 68ba772cc0 Re-submit r289925 (Update .debug_line section version to match DWARF version)
Set the .debug_line version to match the requested DWARF version,
except with a maximum of v4 because we don't support v5 yet.

Previously Chromium had issues with this patch; see PR31407.  Chromium
tool issues have been addressed, so hopefully this will go through
this time.

Patch by Katya Romanova!

Differential Revision: https://reviews.llvm.org/D38002

llvm-svn: 319699
2017-12-04 21:27:46 +00:00
Francis Visoiu Mistrih 25528d6de7 [CodeGen] Unify MBB reference format in both MIR and debug output
As part of the unification of the debug format and the MIR format, print
MBB references as '%bb.5'.

The MIR printer prints the IR name of a MBB only for block definitions.

* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#" << ([a-zA-Z0-9_]+)->getNumber\(\)/" << printMBBReference(*\1)/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#" << ([a-zA-Z0-9_]+)\.getNumber\(\)/" << printMBBReference(\1)/g'
* find . \( -name "*.txt" -o -name "*.s" -o -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#([0-9]+)/%bb.\1/g'
* grep -nr 'BB#' and fix

Differential Revision: https://reviews.llvm.org/D40422

llvm-svn: 319665
2017-12-04 17:18:51 +00:00
Jonas Devlieghere 26f9a0c529 [dwarfdump] Add verbose output for .debug-line section
This patch adds dumping of line table instructions as well as the final
state at each specified pc value in verbose mode. This is essentially
the same as the default in Darwin's dwarfdump. Dumping the actual line
table opcodes can be particularly useful for something like debugging a
bad `.debug_line` section.

Differential revision: https://reviews.llvm.org/D37971

llvm-svn: 313910
2017-09-21 20:15:30 +00:00
Adrian Prantl 16aa4cf7ef llvm-dwarfdump: Make -brief the default and add a -verbose option instead.
Differential Revision: https://reviews.llvm.org/D37717

llvm-svn: 312972
2017-09-11 23:05:20 +00:00
Adrian Prantl 7bc1b28291 llvm-dwarfdump: Replace -debug-dump=sect option with individual options.
As discussed on llvm-dev in
http://lists.llvm.org/pipermail/llvm-dev/2017-September/117301.html
this changes the command line interface of llvm-dwarfdump to match the
one used by the dwarfdump utility shipping on macOS. In addition to
being shorter to type this format also has the advantage of allowing
more than one section to be specified at the same time.

In a nutshell, with this change

  $ llvm-dwarfdump --debug-dump=info
  $ llvm-dwarfdump --debug-dump=apple-objc

becomes

  $ dwarfdump --debug-info --apple-objc

Differential Revision: https://reviews.llvm.org/D37714

llvm-svn: 312970
2017-09-11 22:59:45 +00:00
Tim Northover 14302fcb24 ARM: use an external relocation for calls from MachO ARM mode.
The internal (__text-relative) relocation risks the offset not being encodable
if the destination is Thumb.

llvm-svn: 311187
2017-08-18 19:13:56 +00:00
Peter Collingbourne 89061b2224 IR: Replace the "Linker Options" module flag with "llvm.linker.options" named metadata.
The new metadata is easier to manipulate than module flags.

Differential Revision: https://reviews.llvm.org/D31349

llvm-svn: 305227
2017-06-12 20:10:48 +00:00
Evgeniy Stepanov 60d411b66e [MachO] Fix codegen of alias of alias.
Fixes PR33316.

llvm-svn: 305012
2017-06-08 20:49:03 +00:00
Matthias Braun 8d115a384c MCMacho: Allow __thread_ptr section after dwarf sections
Differential Revision: https://reviews.llvm.org/D29315

llvm-svn: 293730
2017-02-01 01:31:36 +00:00
Steven Wu 5b54a42c0f Add LC_BUILD_VERSION load command
Summary:
Add a new load command LC_BUILD_VERSION. It is a generic version of
LC_*_VERSION_MIN load_command used on Apple platforms. Instead of having
a seperate load command for each platform, LC_BUILD_VERSION is recording
platform info as an enum. It also records SDK version, min_os, and tools
that used to build the binary.

rdar://problem/29781291

Reviewers: enderby

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D29044

llvm-svn: 292824
2017-01-23 20:07:55 +00:00
Nico Weber c4d695e25b Speculatively revert r289925, see PR31407
llvm-svn: 289944
2016-12-16 14:02:28 +00:00