Commit Graph

3045 Commits

Author SHA1 Message Date
Zachary Turner
c371307e60 Use ADDITIONAL_HEADER_DIRS in all LLVM CMake projects.
This allows IDEs to recognize the entire set of header files for
each of the core LLVM projects.

Differential Revision: http://reviews.llvm.org/D7526
Reviewed By: Chris Bieneman

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228798 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-11 03:28:02 +00:00
Bradley Smith
cec93b661d [ARM] Add armv6s[-]m as an alias to armv6[-]m
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228696 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-10 15:15:08 +00:00
Zachary Turner
afd23204f0 Teach llvm_add_library() to find include dirs.
Since header files are not compilation units, CMake does not require
you to specify them in the CMakeLists.txt file.  As a result, unless a
header file is explicitly added, CMake won't know about it, and when
generating IDE-based projects, CMake won't put the header files into
the IDE project.  LLVM currently tries to deal with this in two ways:

  1) It looks for all .h files that are in the project directory, and
     adds those.
  2) llvm_add_library() understands the ADDITIONAL_HEADERS argument,
     which allows one to list an arbitrary list of headers.

This patch takes things one step further.  It adds the ability for
llvm_add_library() to take an ADDITIONAL_HEADER_DIRS argument, which
will specify a list of folders which CMake will glob for header files.
Furthermore, it will glob not only for .h files, but also for .inc
files.

Included in this CL is an update to one of the existing users of
ADDITIONAL_HEADERS to use this new argument instead, to serve as an
illustration of how this cleans up the CMake.

The big advantage of this new approach is that until now, there was no
way for the IDE projects to locate the header files that are in the
include tree.  In other words, if you are in, for example,
lib/DebugInfo/DWARF, the corresponding includes for this project will
be located under include/llvm/DebugInfo/DWARF.  Now, in the
CMakeLists.txt for lib/DebugInfo/DWARF, you can simply write:

  ADDITIONAL_HEADER_DIRS
  ../../include/llvm/DebugInfo/DWARF

as an argument to llvm_add_library(), and all header files will get
added to the IDE project.

Differential Revision: http://reviews.llvm.org/D7460
Reviewed By: Chris Bieneman

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228670 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-10 05:04:37 +00:00
Ben Langmuir
ea280d963d Reduce the LockFileManager timeout, and provide unsafeRemoveLockFile
5 minutes is an eternity, so try to strike a better balance between
waiting long enough for any reasonable module build and not so long that
users kill the process because they think it's hanging.

Also give the client a way to delete the lock file after a timeout.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228603 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-09 20:34:24 +00:00
Zachary Turner
3afd6d0734 Make UTF8->UTF16 conversion null terminate output on empty input.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228527 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-08 18:08:51 +00:00
Joerg Sonnenberger
128482cfc4 Avoid integer overflows around realloc calls resulting in potential
heap. Problem identified by Guido Vranken. Changes differ from original
OpenBSD sources by not depending on non-portable reallocarray.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228507 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-07 21:24:06 +00:00
Duncan P. N. Exon Smith
5a504d487c Support: Add dwarf::getVirtuality()
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228474 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-07 00:37:15 +00:00
Duncan P. N. Exon Smith
a496490358 Support: Use Dwarf.def for DW_VIRTUALITY, NFC
Use definition file for `DW_VIRTUALITY_*`.  Add a `DW_VIRTUALITY_max`
both for ease of testing and for future use by the `LLParser`.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228473 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-07 00:36:23 +00:00
Duncan P. N. Exon Smith
e29c334dd4 Support: Add dwarf::getAttributeEncoding()
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228470 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-06 23:46:49 +00:00
Duncan P. N. Exon Smith
87c9a125d8 Support: Rewrite AttributeEncodingString(), NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228469 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-06 23:45:37 +00:00
Duncan P. N. Exon Smith
f0d7e8a1b8 Support: Stop stringifying DW_ATE_{lo,hi}_user
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228468 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-06 23:44:24 +00:00
Duncan P. N. Exon Smith
81bb18728b Support: Add dwarf::getLanguage()
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228458 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-06 22:55:13 +00:00
Duncan P. N. Exon Smith
e0916cdbc4 Support: Rewrite dwarf::LanguageString(), NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228457 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-06 22:53:19 +00:00
Duncan P. N. Exon Smith
42f3b502ce Support: Stop stringifying DW_LANG_{lo,hi}_user
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228451 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-06 22:34:48 +00:00
Benjamin Kramer
e003f1ac8c Make helper functions/classes/globals static. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228410 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-06 17:51:54 +00:00
Alexey Samsonov
282314741d SpecialCaseList: Add support for parsing multiple input files.
Summary:
This change allows users to create SpecialCaseList objects from
multiple local files. This is needed to implement a proper support
for -fsanitize-blacklist flag (allow users to specify multiple blacklists,
in addition to default blacklist, see PR22431).

DFSan can also benefit from this change, as DFSan instrumentation pass now
accepts ABI-lists both from -fsanitize-blacklist= and -mllvm -dfsan-abilist flags.

Go bindings are fixed accordingly.

Test Plan: regression test suite

Reviewers: pcc

Subscribers: llvm-commits, axw, kcc

Differential Revision: http://reviews.llvm.org/D7367

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228155 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-04 17:39:48 +00:00
Duncan P. N. Exon Smith
5ff000f15e Support: Add string => unsigned mapping for DW_TAG
Add `dwarf::getTag()` to translate from `StringRef` to `unsigned`.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228031 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 21:16:49 +00:00
Duncan P. N. Exon Smith
b3d53c6065 Support: Re-implement dwarf::TagString() using a .def file, NFC
Also re-implements the `dwarf::Tag` enumerator.  I've moved the mock
tags into the enumerator since there's no other way to do this.  Really
they shouldn't be used at all (they're just a hack to identify
`MDNode`s, but we have a class hierarchy for that now).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228030 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 21:13:16 +00:00
Duncan P. N. Exon Smith
17e8d42c63 Support: Stop stringifying DW_TAG_{lo,hi}_user
`dwarf::TagString()` shouldn't stringify `DW_TAG_lo_user` or
`DW_TAG_hi_user`.  These aren't actual tags; they're markers for the
edge of vendor-specific tag regions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228029 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 21:08:33 +00:00
Chris Bieneman
2048ee38ab NFC. Making printOptionValues an API on the parser class.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227626 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-30 22:16:01 +00:00
NAKAMURA Takumi
d379c6b491 [Cygming] Seek also chkstk_ms, or JIT fails with DLL builds. It is fixup for r227519.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227574 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-30 13:01:19 +00:00
Chris Bieneman
39687b93fa iOS doesn't have crt_externs.h available, so we fall back to the posix method.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227521 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-30 00:10:39 +00:00
Aaron Ballman
1b7b2597d5 All signal handlers are required to have C language linkage in C++. This does not fix all signal handlers, but does fix the most recent one.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227490 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-29 20:48:34 +00:00
Michael J. Spencer
9565549e5d [Support][Windows] Unify dialog box suppression and print stack traces on abort.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227470 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-29 17:20:29 +00:00
NAKAMURA Takumi
760c72110f CommandLineParser: Avoid non-static member nitializer(s).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227428 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-29 11:06:59 +00:00
Owen Anderson
b326bdc595 Fix the preprocessor checks used to determine if backtraces have been enabled.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227424 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-29 07:53:13 +00:00
Owen Anderson
e9cc6bd43f Use the existing build configuration parameter ENABLE_BACKTRACE to compile out all pretty stack trace support when backtraces are disabled.
This has the nice secondary effect of allowing LLVM to continue to build
for targets without __thread or thread_local support to continue to work
so long as they build without support for backtraces.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227423 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-29 07:35:31 +00:00
Chandler Carruth
54e0791182 [LPM] Clean up the use of TLS in pretty stack trace and disable it
entirely when threads are not enabled. This should allow anyone who
needs to bootstrap or cope with a host loader without TLS support to
limp along without threading support.

There is still some bug in the PPC TLS stuff that is not worked around.
I'm getting access to a machine to reproduce and debug this further.
There is some chance that I'll have to add a terrible workaround for
PPC.

There is also some problem with iOS, but I have no ability to really
evaluate what the issue is there. I'm leaving it to folks maintaining
that platform to suggest a path forward -- personally I don't see any
useful path forward that supports threading in LLVM but does so without
support for *very basic* TLS. Note that we don't need more than some
pointers, and we don't need constructors, destructors, or any of the
other fanciness which remains widely unimplemented.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227411 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-29 01:23:04 +00:00
Chandler Carruth
41e59785c1 [LPM] Fix the PPC attribute to be spelled 'global-dynamic'. This should
let the build bot make finish compiling stage2.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227391 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-28 23:10:57 +00:00
Chris Bieneman
75a1a5c24b Build fix for Visual Studio. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227385 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-28 22:25:00 +00:00
Chandler Carruth
2aefa011df [LPM] Try to work around a bug with local-dynamic TLS on PowerPC 64.
Sadly, this precludes optimizing it down to initial-exec or local-exec
when statically linking, and in general makes the code slower on PPC 64,
but there's nothing else for it until we can arrange to produce the
correct bits for the linker.

Lots of thanks to Ulirch for tracking this down and Bill for working on
the long-term fix to LLVM so that we can relegate this to old host
clang versions.

I'll be watching the PPC build bots to make sure this effectively
revives them.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227352 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-28 19:29:22 +00:00
Chris Bieneman
61b9b31ef1 Refactoring llvm command line parsing and option registration.
Summary:
The primary goal of this patch is to remove the need for MarkOptionsChanged(). That goal is accomplished by having addOption and removeOption properly sort the options.

This patch puts the new add and remove functionality on a CommandLineParser class that is a placeholder. Some of the functionality in this class will need to be merged into the OptionRegistry, and other bits can hopefully be in a better abstraction.

This patch also removes the RegisteredOptionList global, and the need for cl::Option objects to be linked list nodes.

The changes in CommandLineTest.cpp are required because these changes shift when we validate that options are not duplicated. Before this change duplicate options were only found during certain cl API calls (like cl::ParseCommandLine). With this change duplicate options are found during option construction.

Reviewers: dexonsmith, chandlerc, pete

Reviewed By: pete

Subscribers: pete, majnemer, llvm-commits

Differential Revision: http://reviews.llvm.org/D7132

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227345 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-28 19:00:25 +00:00
Colin LeMahieu
4b032d5f15 [Hexagon] Replacing intrinsics for halfword adds and max/min word/dword.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227322 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-28 17:06:40 +00:00
Chandler Carruth
d5bce3cab0 [LPM] Rip all of ManagedStatic and ThreadLocal out of the pretty stack
tracing code.

Managed static was just insane overhead for this. We took memory fences
and external function calls in every path that pushed a pretty stack
frame. This includes a multitude of layers setting up and tearing down
passes, the parser in Clang, everywhere. For the regression test suite
or low-overhead JITs, this was contributing to really significant
overhead.

Even the LLVM ThreadLocal is really overkill here because it uses
pthread_{set,get}_specific logic, and has careful code to both allocate
and delete the thread local data. We don't actually want any of that,
and this code in particular has problems coping with deallocation. What
we want is a single TLS pointer that is valid to use during global
construction and during global destruction, any time we want. That is
exactly what every host compiler and OS we use has implemented for
a long time, and what was standardized in C++11. Even though not all of
our host compilers support the thread_local keyword, we can directly use
the platform-specific keywords to get the minimal functionality needed.
Provided this limited trial survives the build bots, I will move this to
Compiler.h so it is more widely available as a light weight if limited
alternative to the ThreadLocal class. Many thanks to David Majnemer for
helping me think through the implications across platforms and craft the
MSVC-compatible syntax.

The end result is *substantially* faster. When running llc in a tight
loop over a small IR file targeting the aarch64 backend, this improves
its performance by over 10% for me. It also seems likely to fix the
remaining regressions seen by JIT users with threading enabled.

This may actually have more impact on real-world compile times due to
the use of the pretty stack tracing utility throughout the rest of Clang
or LLVM, but I've not collected any detailed measurements.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227300 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-28 09:52:14 +00:00
Petar Jovanovic
6f2698140e [mips] Use __clear_cache builtin instead of cacheflush()
Use __clear_cache builtin instead of cacheflush() in
Unix Memory::InvalidateInstructionCache().

Differential Revision: http://reviews.llvm.org/D7198


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227269 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-27 23:30:18 +00:00
Chris Bieneman
4990e83b7b Re-landing changes to use ArrayRef instead of SmallVectorImpl, and new API test.
This contains the changes from r227148 & r227154, and also fixes to the test case to properly clean up the stack options.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227255 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-27 22:21:06 +00:00
Richard Trieu
510cadb1c2 Revert r227148 & r227154 which added a test which infinitely loops.
r227148 added test CommandLineTest.HideUnrelatedOptionsMulti which repeatedly
outputs two following lines:

-tool: CommandLine Error: Option 'test-option-1' registered more than once!
-tool: CommandLine Error: Option 'test-option-2' registered more than once!

r227154 depends on changes from r227148


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227167 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-27 03:03:47 +00:00
Chris Bieneman
57d5adfe15 One more fix to the new API to fix const-correctness.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227154 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-27 00:42:00 +00:00
Chris Bieneman
f96362358f Pete Cooper suggested the new API should use ArrayRef instead of SmallVectorImpl. Also adding a test case.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227148 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-26 22:50:47 +00:00
Zachary Turner
b9a39da95e Have the UTF conversion wrappers append a null terminator.
This is especially useful for the UTF8 -> UTF16 direction, since
there is no equivalent of llvm::SmallString<> for wide characters.
This means that anyone who wants a null terminated string is forced
to manually push and pop their own null terminator.

Reviewed by: Reid Kleckner.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227143 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-26 22:05:50 +00:00
Chris Bieneman
7006a12ba3 Add new HideUnrelatedOptions API that takes a SmallVectorImpl.
Need a new API for clang-modernize that allows specifying a list of option categories to remain visible. This will allow clang-modernize to move off getRegisteredOptions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227140 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-26 21:57:29 +00:00
Reid Kleckner
91ccead42a Add a UTF8 to UTF16 conversion wrapper for use in the pdb dumper
This can also be used instead of the WindowsSupport.h ConvertUTF8ToUTF16
helpers, but that will require massaging some character types. The
Windows support routines want wchar_t output, but wchar_t is often 32
bits on non-Windows OSs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227122 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-26 19:51:00 +00:00
Zachary Turner
019c097d1b Teach raw_ostream to support hex formatting without a prefix '0x'.
Previously using format_hex() would always print a 0x prior to the
hex characters.  This allows this to be optional, so that one can
choose to print (e.g.) 255 as either 0xFF or just FF.

Differential Revision: http://reviews.llvm.org/D7151

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227108 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-26 18:21:33 +00:00
Alex Rosenberg
583a153662 Remove trailing whitespace. NFC ®
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227105 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-26 18:02:18 +00:00
Michael J. Spencer
58fed4d65a [Support][Windows] Disable error dialog boxes when stack trace printing is enabled.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227094 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-26 17:05:02 +00:00
Chris Bieneman
e0c2d280a2 Putting all the standard tool options into a "Generic" category.
Summary:
This puts all the options that CommandLine.cpp implements into a category so that the APIs to hide options can not hide based on the generic category instead of string matching a partial list of argument strings.

This patch is pretty simple and straight forward but it does impact the -help output of all tools using cl::opt. Specifically the options implemented in CommandLine.cpp (help, help-list, help-hidden, help-list-hidden, print-options, print-all-options, version) are all grouped together into an Option category, and these options are never hidden by the cl::HideUnrelatedOptions API.

Reviewers: dexonsmith, chandlerc, majnemer

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D7150

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227093 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-26 16:56:00 +00:00
Joerg Sonnenberger
d546b25ddb The canonical CPU variant for ARM according to config.guess uses a
suffix it seems:

    # ./config.guess
    earmv7hfeb-unknown-netbsd7.99.4

Extend the triple parsing to support this. Avoid running the ARM parser
multiple times because StringSwitch is not lazy.

Reviewers: Renato Golin, Tim Northover

Differential Revision: http://reviews.llvm.org/D7166


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227085 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-26 11:41:48 +00:00
Alex Rosenberg
f6c7255d5f Add the triple for the Sony Playstation®4.
Lots more to follow.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227060 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-25 22:46:59 +00:00
Alexei Starovoitov
4fe85c7548 BPF backend
Summary:
V8->V9:
- cleanup tests

V7->V8:
- addressed feedback from David:
- switched to range-based 'for' loops
- fixed formatting of tests

V6->V7:
- rebased and adjusted AsmPrinter args
- CamelCased .td, fixed formatting, cleaned up names, removed unused patterns
- diffstat: 3 files changed, 203 insertions(+), 227 deletions(-)

V5->V6:
- addressed feedback from Chandler:
- reinstated full verbose standard banner in all files
- fixed variables that were not in CamelCase
- fixed names of #ifdef in header files
- removed redundant braces in if/else chains with single statements
- fixed comments
- removed trailing empty line
- dropped debug annotations from tests
- diffstat of these changes:
  46 files changed, 456 insertions(+), 469 deletions(-)

V4->V5:
- fix setLoadExtAction() interface
- clang-formated all where it made sense

V3->V4:
- added CODE_OWNERS entry for BPF backend

V2->V3:
- fix metadata in tests

V1->V2:
- addressed feedback from Tom and Matt
- removed top level change to configure (now everything via 'experimental-backend')
- reworked error reporting via DiagnosticInfo (similar to R600)
- added few more tests
- added cmake build
- added Triple::bpf
- tested on linux and darwin

V1 cover letter:
---------------------
recently linux gained "universal in-kernel virtual machine" which is called
eBPF or extended BPF. The name comes from "Berkeley Packet Filter", since
new instruction set is based on it.
This patch adds a new backend that emits extended BPF instruction set.

The concept and development are covered by the following articles:
http://lwn.net/Articles/599755/
http://lwn.net/Articles/575531/
http://lwn.net/Articles/603983/
http://lwn.net/Articles/606089/
http://lwn.net/Articles/612878/

One of use cases: dtrace/systemtap alternative.

bpf syscall manpage:
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=b4fc1a460f3017e958e6a8ea560ea0afd91bf6fe

instruction set description and differences vs classic BPF:
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/Documentation/networking/filter.txt

Short summary of instruction set:
- 64-bit registers
  R0      - return value from in-kernel function, and exit value for BPF program
  R1 - R5 - arguments from BPF program to in-kernel function
  R6 - R9 - callee saved registers that in-kernel function will preserve
  R10     - read-only frame pointer to access stack
- two-operand instructions like +, -, *, mov, load/store
- implicit prologue/epilogue (invisible stack pointer)
- no floating point, no simd

Short history of extended BPF in kernel:
interpreter in 3.15, x64 JIT in 3.16, arm64 JIT, verifier, bpf syscall in 3.18, more to come in the future.

It's a very small and simple backend.
There is no support for global variables, arbitrary function calls, floating point, varargs,
exceptions, indirect jumps, arbitrary pointer arithmetic, alloca, etc.
From C front-end point of view it's very restricted. It's done on purpose, since kernel
rejects all programs that it cannot prove safe. It rejects programs with loops
and with memory accesses via arbitrary pointers. When kernel accepts the program it is
guaranteed that program will terminate and will not crash the kernel.

This patch implements all 'must have' bits. There are several things on TODO list,
so this is not the end of development.
Most of the code is a boiler plate code, copy-pasted from other backends.
Only odd things are lack or < and <= instructions, specialized load_byte intrinsics
and 'compare and goto' as single instruction.
Current instruction set is fixed, but more instructions can be added in the future.

Signed-off-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>

Subscribers: majnemer, chandlerc, echristo, joerg, pete, rengolin, kristof.beyls, arsenm, t.p.northover, tstellarAMD, aemerson, llvm-commits

Differential Revision: http://reviews.llvm.org/D6494

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227008 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-24 17:51:26 +00:00
Yunzhong Gao
d3198ce4bc If we see UTF-8 BOM sequence at the beginning of a response file, we shall
remove these bytes before parsing.

Phabricator Revision: http://reviews.llvm.org/D7156



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226988 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-24 04:23:08 +00:00